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TOMOYO Linux Cross Reference
Linux/arch/powerpc/kernel/exceptions-64s.S

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  1 /* SPDX-License-Identifier: GPL-2.0 */
  2 /*
  3  * This file contains the 64-bit "server" PowerPC variant
  4  * of the low level exception handling including exception
  5  * vectors, exception return, part of the slb and stab
  6  * handling and other fixed offset specific things.
  7  *
  8  * This file is meant to be #included from head_64.S due to
  9  * position dependent assembly.
 10  *
 11  * Most of this originates from head_64.S and thus has the same
 12  * copyright history.
 13  *
 14  */
 15 
 16 #include <linux/linkage.h>
 17 #include <asm/hw_irq.h>
 18 #include <asm/exception-64s.h>
 19 #include <asm/ptrace.h>
 20 #include <asm/cpuidle.h>
 21 #include <asm/head-64.h>
 22 #include <asm/feature-fixups.h>
 23 #include <asm/kup.h>
 24 
 25 /*
 26  * Following are fixed section helper macros.
 27  *
 28  * EXC_REAL_BEGIN/END  - real, unrelocated exception vectors
 29  * EXC_VIRT_BEGIN/END  - virt (AIL), unrelocated exception vectors
 30  * TRAMP_REAL_BEGIN    - real, unrelocated helpers (virt may call these)
 31  * TRAMP_VIRT_BEGIN    - virt, unreloc helpers (in practice, real can use)
 32  * EXC_COMMON          - After switching to virtual, relocated mode.
 33  */
 34 
 35 #define EXC_REAL_BEGIN(name, start, size)                       \
 36         FIXED_SECTION_ENTRY_BEGIN_LOCATION(real_vectors, exc_real_##start##_##name, start, size)
 37 
 38 #define EXC_REAL_END(name, start, size)                         \
 39         FIXED_SECTION_ENTRY_END_LOCATION(real_vectors, exc_real_##start##_##name, start, size)
 40 
 41 #define EXC_VIRT_BEGIN(name, start, size)                       \
 42         FIXED_SECTION_ENTRY_BEGIN_LOCATION(virt_vectors, exc_virt_##start##_##name, start, size)
 43 
 44 #define EXC_VIRT_END(name, start, size)                         \
 45         FIXED_SECTION_ENTRY_END_LOCATION(virt_vectors, exc_virt_##start##_##name, start, size)
 46 
 47 #define EXC_COMMON_BEGIN(name)                                  \
 48         USE_TEXT_SECTION();                                     \
 49         .balign IFETCH_ALIGN_BYTES;                             \
 50         .global name;                                           \
 51         _ASM_NOKPROBE_SYMBOL(name);                             \
 52         DEFINE_FIXED_SYMBOL(name, text);                        \
 53 name:
 54 
 55 #define TRAMP_REAL_BEGIN(name)                                  \
 56         FIXED_SECTION_ENTRY_BEGIN(real_trampolines, name)
 57 
 58 #define TRAMP_VIRT_BEGIN(name)                                  \
 59         FIXED_SECTION_ENTRY_BEGIN(virt_trampolines, name)
 60 
 61 #define EXC_REAL_NONE(start, size)                              \
 62         FIXED_SECTION_ENTRY_BEGIN_LOCATION(real_vectors, exc_real_##start##_##unused, start, size); \
 63         FIXED_SECTION_ENTRY_END_LOCATION(real_vectors, exc_real_##start##_##unused, start, size)
 64 
 65 #define EXC_VIRT_NONE(start, size)                              \
 66         FIXED_SECTION_ENTRY_BEGIN_LOCATION(virt_vectors, exc_virt_##start##_##unused, start, size); \
 67         FIXED_SECTION_ENTRY_END_LOCATION(virt_vectors, exc_virt_##start##_##unused, start, size)
 68 
 69 /*
 70  * We're short on space and time in the exception prolog, so we can't
 71  * use the normal LOAD_REG_IMMEDIATE macro to load the address of label.
 72  * Instead we get the base of the kernel from paca->kernelbase and or in the low
 73  * part of label. This requires that the label be within 64KB of kernelbase, and
 74  * that kernelbase be 64K aligned.
 75  */
 76 #define LOAD_HANDLER(reg, label)                                        \
 77         ld      reg,PACAKBASE(r13);     /* get high part of &label */   \
 78         ori     reg,reg,FIXED_SYMBOL_ABS_ADDR(label)
 79 
 80 #define __LOAD_HANDLER(reg, label, section)                                     \
 81         ld      reg,PACAKBASE(r13);                                     \
 82         ori     reg,reg,(ABS_ADDR(label, section))@l
 83 
 84 /*
 85  * Branches from unrelocated code (e.g., interrupts) to labels outside
 86  * head-y require >64K offsets.
 87  */
 88 #define __LOAD_FAR_HANDLER(reg, label, section)                                 \
 89         ld      reg,PACAKBASE(r13);                                     \
 90         ori     reg,reg,(ABS_ADDR(label, section))@l;                           \
 91         addis   reg,reg,(ABS_ADDR(label, section))@h
 92 
 93 /*
 94  * Interrupt code generation macros
 95  */
 96 #define IVEC            .L_IVEC_\name\()        /* Interrupt vector address */
 97 #define IHSRR           .L_IHSRR_\name\()       /* Sets SRR or HSRR registers */
 98 #define IHSRR_IF_HVMODE .L_IHSRR_IF_HVMODE_\name\() /* HSRR if HV else SRR */
 99 #define IAREA           .L_IAREA_\name\()       /* PACA save area */
100 #define IVIRT           .L_IVIRT_\name\()       /* Has virt mode entry point */
101 #define IISIDE          .L_IISIDE_\name\()      /* Uses SRR0/1 not DAR/DSISR */
102 #define ICFAR           .L_ICFAR_\name\()       /* Uses CFAR */
103 #define ICFAR_IF_HVMODE .L_ICFAR_IF_HVMODE_\name\() /* Uses CFAR if HV */
104 #define IDAR            .L_IDAR_\name\()        /* Uses DAR (or SRR0) */
105 #define IDSISR          .L_IDSISR_\name\()      /* Uses DSISR (or SRR1) */
106 #define IBRANCH_TO_COMMON       .L_IBRANCH_TO_COMMON_\name\() /* ENTRY branch to common */
107 #define IREALMODE_COMMON        .L_IREALMODE_COMMON_\name\() /* Common runs in realmode */
108 #define IMASK           .L_IMASK_\name\()       /* IRQ soft-mask bit */
109 #define IKVM_REAL       .L_IKVM_REAL_\name\()   /* Real entry tests KVM */
110 #define __IKVM_REAL(name)       .L_IKVM_REAL_ ## name
111 #define IKVM_VIRT       .L_IKVM_VIRT_\name\()   /* Virt entry tests KVM */
112 #define ISTACK          .L_ISTACK_\name\()      /* Set regular kernel stack */
113 #define __ISTACK(name)  .L_ISTACK_ ## name
114 #define IKUAP           .L_IKUAP_\name\()       /* Do KUAP lock */
115 #define IMSR_R12        .L_IMSR_R12_\name\()    /* Assumes MSR saved to r12 */
116 
117 #define INT_DEFINE_BEGIN(n)                                             \
118 .macro int_define_ ## n name
119 
120 #define INT_DEFINE_END(n)                                               \
121 .endm ;                                                                 \
122 int_define_ ## n n ;                                                    \
123 do_define_int n
124 
125 .macro do_define_int name
126         .ifndef IVEC
127                 .error "IVEC not defined"
128         .endif
129         .ifndef IHSRR
130                 IHSRR=0
131         .endif
132         .ifndef IHSRR_IF_HVMODE
133                 IHSRR_IF_HVMODE=0
134         .endif
135         .ifndef IAREA
136                 IAREA=PACA_EXGEN
137         .endif
138         .ifndef IVIRT
139                 IVIRT=1
140         .endif
141         .ifndef IISIDE
142                 IISIDE=0
143         .endif
144         .ifndef ICFAR
145                 ICFAR=1
146         .endif
147         .ifndef ICFAR_IF_HVMODE
148                 ICFAR_IF_HVMODE=0
149         .endif
150         .ifndef IDAR
151                 IDAR=0
152         .endif
153         .ifndef IDSISR
154                 IDSISR=0
155         .endif
156         .ifndef IBRANCH_TO_COMMON
157                 IBRANCH_TO_COMMON=1
158         .endif
159         .ifndef IREALMODE_COMMON
160                 IREALMODE_COMMON=0
161         .else
162                 .if ! IBRANCH_TO_COMMON
163                         .error "IREALMODE_COMMON=1 but IBRANCH_TO_COMMON=0"
164                 .endif
165         .endif
166         .ifndef IMASK
167                 IMASK=0
168         .endif
169         .ifndef IKVM_REAL
170                 IKVM_REAL=0
171         .endif
172         .ifndef IKVM_VIRT
173                 IKVM_VIRT=0
174         .endif
175         .ifndef ISTACK
176                 ISTACK=1
177         .endif
178         .ifndef IKUAP
179                 IKUAP=1
180         .endif
181         .ifndef IMSR_R12
182                 IMSR_R12=0
183         .endif
184 .endm
185 
186 /*
187  * All interrupts which set HSRR registers, as well as SRESET and MCE and
188  * syscall when invoked with "sc 1" switch to MSR[HV]=1 (HVMODE) to be taken,
189  * so they all generally need to test whether they were taken in guest context.
190  *
191  * Note: SRESET and MCE may also be sent to the guest by the hypervisor, and be
192  * taken with MSR[HV]=0.
193  *
194  * Interrupts which set SRR registers (with the above exceptions) do not
195  * elevate to MSR[HV]=1 mode, though most can be taken when running with
196  * MSR[HV]=1  (e.g., bare metal kernel and userspace). So these interrupts do
197  * not need to test whether a guest is running because they get delivered to
198  * the guest directly, including nested HV KVM guests.
199  *
200  * The exception is PR KVM, where the guest runs with MSR[PR]=1 and the host
201  * runs with MSR[HV]=0, so the host takes all interrupts on behalf of the
202  * guest. PR KVM runs with LPCR[AIL]=0 which causes interrupts to always be
203  * delivered to the real-mode entry point, therefore such interrupts only test
204  * KVM in their real mode handlers, and only when PR KVM is possible.
205  *
206  * Interrupts that are taken in MSR[HV]=0 and escalate to MSR[HV]=1 are always
207  * delivered in real-mode when the MMU is in hash mode because the MMU
208  * registers are not set appropriately to translate host addresses. In nested
209  * radix mode these can be delivered in virt-mode as the host translations are
210  * used implicitly (see: effective LPID, effective PID).
211  */
212 
213 /*
214  * If an interrupt is taken while a guest is running, it is immediately routed
215  * to KVM to handle.
216  */
217 
218 .macro KVMTEST name handler
219 #ifdef CONFIG_KVM_BOOK3S_64_HANDLER
220         lbz     r10,HSTATE_IN_GUEST(r13)
221         cmpwi   r10,0
222         /* HSRR variants have the 0x2 bit added to their trap number */
223         .if IHSRR_IF_HVMODE
224         BEGIN_FTR_SECTION
225         li      r10,(IVEC + 0x2)
226         FTR_SECTION_ELSE
227         li      r10,(IVEC)
228         ALT_FTR_SECTION_END_IFSET(CPU_FTR_HVMODE | CPU_FTR_ARCH_206)
229         .elseif IHSRR
230         li      r10,(IVEC + 0x2)
231         .else
232         li      r10,(IVEC)
233         .endif
234         bne     \handler
235 #endif
236 .endm
237 
238 /*
239  * This is the BOOK3S interrupt entry code macro.
240  *
241  * This can result in one of several things happening:
242  * - Branch to the _common handler, relocated, in virtual mode.
243  *   These are normal interrupts (synchronous and asynchronous) handled by
244  *   the kernel.
245  * - Branch to KVM, relocated but real mode interrupts remain in real mode.
246  *   These occur when HSTATE_IN_GUEST is set. The interrupt may be caused by
247  *   / intended for host or guest kernel, but KVM must always be involved
248  *   because the machine state is set for guest execution.
249  * - Branch to the masked handler, unrelocated.
250  *   These occur when maskable asynchronous interrupts are taken with the
251  *   irq_soft_mask set.
252  * - Branch to an "early" handler in real mode but relocated.
253  *   This is done if early=1. MCE and HMI use these to handle errors in real
254  *   mode.
255  * - Fall through and continue executing in real, unrelocated mode.
256  *   This is done if early=2.
257  */
258 
259 .macro GEN_BRANCH_TO_COMMON name, virt
260         .if IREALMODE_COMMON
261         LOAD_HANDLER(r10, \name\()_common)
262         mtctr   r10
263         bctr
264         .else
265         .if \virt
266 #ifndef CONFIG_RELOCATABLE
267         b       \name\()_common_virt
268 #else
269         LOAD_HANDLER(r10, \name\()_common_virt)
270         mtctr   r10
271         bctr
272 #endif
273         .else
274         LOAD_HANDLER(r10, \name\()_common_real)
275         mtctr   r10
276         bctr
277         .endif
278         .endif
279 .endm
280 
281 .macro GEN_INT_ENTRY name, virt, ool=0
282         SET_SCRATCH0(r13)                       /* save r13 */
283         GET_PACA(r13)
284         std     r9,IAREA+EX_R9(r13)             /* save r9 */
285 BEGIN_FTR_SECTION
286         mfspr   r9,SPRN_PPR
287 END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
288         HMT_MEDIUM
289         std     r10,IAREA+EX_R10(r13)           /* save r10 */
290         .if ICFAR
291 BEGIN_FTR_SECTION
292         mfspr   r10,SPRN_CFAR
293 END_FTR_SECTION_IFSET(CPU_FTR_CFAR)
294         .elseif ICFAR_IF_HVMODE
295 BEGIN_FTR_SECTION
296   BEGIN_FTR_SECTION_NESTED(69)
297         mfspr   r10,SPRN_CFAR
298   END_FTR_SECTION_NESTED(CPU_FTR_CFAR, CPU_FTR_CFAR, 69)
299 FTR_SECTION_ELSE
300   BEGIN_FTR_SECTION_NESTED(69)
301         li      r10,0
302   END_FTR_SECTION_NESTED(CPU_FTR_CFAR, CPU_FTR_CFAR, 69)
303 ALT_FTR_SECTION_END_IFSET(CPU_FTR_HVMODE | CPU_FTR_ARCH_206)
304         .endif
305         .if \ool
306         .if !\virt
307         b       tramp_real_\name
308         .pushsection .text
309         TRAMP_REAL_BEGIN(tramp_real_\name)
310         .else
311         b       tramp_virt_\name
312         .pushsection .text
313         TRAMP_VIRT_BEGIN(tramp_virt_\name)
314         .endif
315         .endif
316 
317 BEGIN_FTR_SECTION
318         std     r9,IAREA+EX_PPR(r13)
319 END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
320         .if ICFAR || ICFAR_IF_HVMODE
321 BEGIN_FTR_SECTION
322         std     r10,IAREA+EX_CFAR(r13)
323 END_FTR_SECTION_IFSET(CPU_FTR_CFAR)
324         .endif
325         INTERRUPT_TO_KERNEL
326         mfctr   r10
327         std     r10,IAREA+EX_CTR(r13)
328         mfcr    r9
329         std     r11,IAREA+EX_R11(r13)           /* save r11 - r12 */
330         std     r12,IAREA+EX_R12(r13)
331 
332         /*
333          * DAR/DSISR, SCRATCH0 must be read before setting MSR[RI],
334          * because a d-side MCE will clobber those registers so is
335          * not recoverable if they are live.
336          */
337         GET_SCRATCH0(r10)
338         std     r10,IAREA+EX_R13(r13)
339         .if IDAR && !IISIDE
340         .if IHSRR
341         mfspr   r10,SPRN_HDAR
342         .else
343         mfspr   r10,SPRN_DAR
344         .endif
345         std     r10,IAREA+EX_DAR(r13)
346         .endif
347         .if IDSISR && !IISIDE
348         .if IHSRR
349         mfspr   r10,SPRN_HDSISR
350         .else
351         mfspr   r10,SPRN_DSISR
352         .endif
353         stw     r10,IAREA+EX_DSISR(r13)
354         .endif
355 
356         .if IHSRR_IF_HVMODE
357         BEGIN_FTR_SECTION
358         mfspr   r11,SPRN_HSRR0          /* save HSRR0 */
359         mfspr   r12,SPRN_HSRR1          /* and HSRR1 */
360         FTR_SECTION_ELSE
361         mfspr   r11,SPRN_SRR0           /* save SRR0 */
362         mfspr   r12,SPRN_SRR1           /* and SRR1 */
363         ALT_FTR_SECTION_END_IFSET(CPU_FTR_HVMODE | CPU_FTR_ARCH_206)
364         .elseif IHSRR
365         mfspr   r11,SPRN_HSRR0          /* save HSRR0 */
366         mfspr   r12,SPRN_HSRR1          /* and HSRR1 */
367         .else
368         mfspr   r11,SPRN_SRR0           /* save SRR0 */
369         mfspr   r12,SPRN_SRR1           /* and SRR1 */
370         .endif
371 
372         .if IBRANCH_TO_COMMON
373         GEN_BRANCH_TO_COMMON \name \virt
374         .endif
375 
376         .if \ool
377         .popsection
378         .endif
379 .endm
380 
381 /*
382  * __GEN_COMMON_ENTRY is required to receive the branch from interrupt
383  * entry, except in the case of the real-mode handlers which require
384  * __GEN_REALMODE_COMMON_ENTRY.
385  *
386  * This switches to virtual mode and sets MSR[RI].
387  */
388 .macro __GEN_COMMON_ENTRY name
389 DEFINE_FIXED_SYMBOL(\name\()_common_real, text)
390 \name\()_common_real:
391         .if IKVM_REAL
392                 KVMTEST \name kvm_interrupt
393         .endif
394 
395         ld      r10,PACAKMSR(r13)       /* get MSR value for kernel */
396         /* MSR[RI] is clear iff using SRR regs */
397         .if IHSRR_IF_HVMODE
398         BEGIN_FTR_SECTION
399         xori    r10,r10,MSR_RI
400         END_FTR_SECTION_IFCLR(CPU_FTR_HVMODE)
401         .elseif ! IHSRR
402         xori    r10,r10,MSR_RI
403         .endif
404         mtmsrd  r10
405 
406         .if IVIRT
407         .if IKVM_VIRT
408         b       1f /* skip the virt test coming from real */
409         .endif
410 
411         .balign IFETCH_ALIGN_BYTES
412 DEFINE_FIXED_SYMBOL(\name\()_common_virt, text)
413 \name\()_common_virt:
414         .if IKVM_VIRT
415                 KVMTEST \name kvm_interrupt
416 1:
417         .endif
418         .endif /* IVIRT */
419 .endm
420 
421 /*
422  * Don't switch to virt mode. Used for early MCE and HMI handlers that
423  * want to run in real mode.
424  */
425 .macro __GEN_REALMODE_COMMON_ENTRY name
426 DEFINE_FIXED_SYMBOL(\name\()_common_real, text)
427 \name\()_common_real:
428         .if IKVM_REAL
429                 KVMTEST \name kvm_interrupt
430         .endif
431 .endm
432 
433 .macro __GEN_COMMON_BODY name
434         .if IMASK
435                 .if ! ISTACK
436                 .error "No support for masked interrupt to use custom stack"
437                 .endif
438 
439                 /* If coming from user, skip soft-mask tests. */
440                 andi.   r10,r12,MSR_PR
441                 bne     3f
442 
443                 /*
444                  * Kernel code running below __end_soft_masked may be
445                  * implicitly soft-masked if it is within the regions
446                  * in the soft mask table.
447                  */
448                 LOAD_HANDLER(r10, __end_soft_masked)
449                 cmpld   r11,r10
450                 bge+    1f
451 
452                 /* SEARCH_SOFT_MASK_TABLE clobbers r9,r10,r12 */
453                 mtctr   r12
454                 stw     r9,PACA_EXGEN+EX_CCR(r13)
455                 SEARCH_SOFT_MASK_TABLE
456                 cmpdi   r12,0
457                 mfctr   r12             /* Restore r12 to SRR1 */
458                 lwz     r9,PACA_EXGEN+EX_CCR(r13)
459                 beq     1f              /* Not in soft-mask table */
460                 li      r10,IMASK
461                 b       2f              /* In soft-mask table, always mask */
462 
463                 /* Test the soft mask state against our interrupt's bit */
464 1:              lbz     r10,PACAIRQSOFTMASK(r13)
465 2:              andi.   r10,r10,IMASK
466                 /* Associate vector numbers with bits in paca->irq_happened */
467                 .if IVEC == 0x500 || IVEC == 0xea0
468                 li      r10,PACA_IRQ_EE
469                 .elseif IVEC == 0x900
470                 li      r10,PACA_IRQ_DEC
471                 .elseif IVEC == 0xa00 || IVEC == 0xe80
472                 li      r10,PACA_IRQ_DBELL
473                 .elseif IVEC == 0xe60
474                 li      r10,PACA_IRQ_HMI
475                 .elseif IVEC == 0xf00
476                 li      r10,PACA_IRQ_PMI
477                 .else
478                 .abort "Bad maskable vector"
479                 .endif
480 
481                 .if IHSRR_IF_HVMODE
482                 BEGIN_FTR_SECTION
483                 bne     masked_Hinterrupt
484                 FTR_SECTION_ELSE
485                 bne     masked_interrupt
486                 ALT_FTR_SECTION_END_IFSET(CPU_FTR_HVMODE | CPU_FTR_ARCH_206)
487                 .elseif IHSRR
488                 bne     masked_Hinterrupt
489                 .else
490                 bne     masked_interrupt
491                 .endif
492         .endif
493 
494         .if ISTACK
495         andi.   r10,r12,MSR_PR          /* See if coming from user      */
496 3:      mr      r10,r1                  /* Save r1                      */
497         subi    r1,r1,INT_FRAME_SIZE    /* alloc frame on kernel stack  */
498         beq-    100f
499         ld      r1,PACAKSAVE(r13)       /* kernel stack to use          */
500 100:    tdgei   r1,-INT_FRAME_SIZE      /* trap if r1 is in userspace   */
501         EMIT_BUG_ENTRY 100b,__FILE__,__LINE__,0
502         .endif
503 
504         std     r9,_CCR(r1)             /* save CR in stackframe        */
505         std     r11,_NIP(r1)            /* save SRR0 in stackframe      */
506         std     r12,_MSR(r1)            /* save SRR1 in stackframe      */
507         std     r10,0(r1)               /* make stack chain pointer     */
508         std     r0,GPR0(r1)             /* save r0 in stackframe        */
509         std     r10,GPR1(r1)            /* save r1 in stackframe        */
510         SANITIZE_GPR(0)
511 
512         /* Mark our [H]SRRs valid for return */
513         li      r10,1
514         .if IHSRR_IF_HVMODE
515         BEGIN_FTR_SECTION
516         stb     r10,PACAHSRR_VALID(r13)
517         FTR_SECTION_ELSE
518         stb     r10,PACASRR_VALID(r13)
519         ALT_FTR_SECTION_END_IFSET(CPU_FTR_HVMODE | CPU_FTR_ARCH_206)
520         .elseif IHSRR
521         stb     r10,PACAHSRR_VALID(r13)
522         .else
523         stb     r10,PACASRR_VALID(r13)
524         .endif
525 
526         .if ISTACK
527         .if IKUAP
528         kuap_save_amr_and_lock r9, r10, cr1, cr0
529         .endif
530         beq     101f                    /* if from kernel mode          */
531 BEGIN_FTR_SECTION
532         ld      r9,IAREA+EX_PPR(r13)    /* Read PPR from paca           */
533         std     r9,_PPR(r1)
534 END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
535 101:
536         .else
537         .if IKUAP
538         kuap_save_amr_and_lock r9, r10, cr1
539         .endif
540         .endif
541 
542         /* Save original regs values from save area to stack frame. */
543         ld      r9,IAREA+EX_R9(r13)     /* move r9, r10 to stackframe   */
544         ld      r10,IAREA+EX_R10(r13)
545         std     r9,GPR9(r1)
546         std     r10,GPR10(r1)
547         ld      r9,IAREA+EX_R11(r13)    /* move r11 - r13 to stackframe */
548         ld      r10,IAREA+EX_R12(r13)
549         ld      r11,IAREA+EX_R13(r13)
550         std     r9,GPR11(r1)
551         std     r10,GPR12(r1)
552         std     r11,GPR13(r1)
553         .if !IMSR_R12
554         SANITIZE_GPRS(9, 12)
555         .else
556         SANITIZE_GPRS(9, 11)
557         .endif
558 
559         SAVE_NVGPRS(r1)
560         SANITIZE_NVGPRS()
561 
562         .if IDAR
563         .if IISIDE
564         ld      r10,_NIP(r1)
565         .else
566         ld      r10,IAREA+EX_DAR(r13)
567         .endif
568         std     r10,_DAR(r1)
569         .endif
570 
571         .if IDSISR
572         .if IISIDE
573         ld      r10,_MSR(r1)
574         lis     r11,DSISR_SRR1_MATCH_64S@h
575         and     r10,r10,r11
576         .else
577         lwz     r10,IAREA+EX_DSISR(r13)
578         .endif
579         std     r10,_DSISR(r1)
580         .endif
581 
582 BEGIN_FTR_SECTION
583         .if ICFAR || ICFAR_IF_HVMODE
584         ld      r10,IAREA+EX_CFAR(r13)
585         .else
586         li      r10,0
587         .endif
588         std     r10,ORIG_GPR3(r1)
589 END_FTR_SECTION_IFSET(CPU_FTR_CFAR)
590         ld      r10,IAREA+EX_CTR(r13)
591         std     r10,_CTR(r1)
592         SAVE_GPRS(2, 8, r1)             /* save r2 - r8 in stackframe   */
593         SANITIZE_GPRS(2, 8)
594         mflr    r9                      /* Get LR, later save to stack  */
595         LOAD_PACA_TOC()                 /* get kernel TOC into r2       */
596         std     r9,_LINK(r1)
597         lbz     r10,PACAIRQSOFTMASK(r13)
598         mfspr   r11,SPRN_XER            /* save XER in stackframe       */
599         std     r10,SOFTE(r1)
600         std     r11,_XER(r1)
601         li      r9,IVEC
602         std     r9,_TRAP(r1)            /* set trap number              */
603         li      r10,0
604         LOAD_REG_IMMEDIATE(r11, STACK_FRAME_REGS_MARKER)
605         std     r10,RESULT(r1)          /* clear regs->result           */
606         std     r11,STACK_INT_FRAME_MARKER(r1) /* mark the frame        */
607 .endm
608 
609 /*
610  * On entry r13 points to the paca, r9-r13 are saved in the paca,
611  * r9 contains the saved CR, r11 and r12 contain the saved SRR0 and
612  * SRR1, and relocation is on.
613  *
614  * If stack=0, then the stack is already set in r1, and r1 is saved in r10.
615  * PPR save and CPU accounting is not done for the !stack case (XXX why not?)
616  */
617 .macro GEN_COMMON name
618         __GEN_COMMON_ENTRY \name
619         __GEN_COMMON_BODY \name
620 .endm
621 
622 .macro SEARCH_RESTART_TABLE
623 #ifdef CONFIG_RELOCATABLE
624         mr      r12,r2
625         LOAD_PACA_TOC()
626         LOAD_REG_ADDR(r9, __start___restart_table)
627         LOAD_REG_ADDR(r10, __stop___restart_table)
628         mr      r2,r12
629 #else
630         LOAD_REG_IMMEDIATE_SYM(r9, r12, __start___restart_table)
631         LOAD_REG_IMMEDIATE_SYM(r10, r12, __stop___restart_table)
632 #endif
633 300:
634         cmpd    r9,r10
635         beq     302f
636         ld      r12,0(r9)
637         cmpld   r11,r12
638         blt     301f
639         ld      r12,8(r9)
640         cmpld   r11,r12
641         bge     301f
642         ld      r12,16(r9)
643         b       303f
644 301:
645         addi    r9,r9,24
646         b       300b
647 302:
648         li      r12,0
649 303:
650 .endm
651 
652 .macro SEARCH_SOFT_MASK_TABLE
653 #ifdef CONFIG_RELOCATABLE
654         mr      r12,r2
655         LOAD_PACA_TOC()
656         LOAD_REG_ADDR(r9, __start___soft_mask_table)
657         LOAD_REG_ADDR(r10, __stop___soft_mask_table)
658         mr      r2,r12
659 #else
660         LOAD_REG_IMMEDIATE_SYM(r9, r12, __start___soft_mask_table)
661         LOAD_REG_IMMEDIATE_SYM(r10, r12, __stop___soft_mask_table)
662 #endif
663 300:
664         cmpd    r9,r10
665         beq     302f
666         ld      r12,0(r9)
667         cmpld   r11,r12
668         blt     301f
669         ld      r12,8(r9)
670         cmpld   r11,r12
671         bge     301f
672         li      r12,1
673         b       303f
674 301:
675         addi    r9,r9,16
676         b       300b
677 302:
678         li      r12,0
679 303:
680 .endm
681 
682 /*
683  * Restore all registers including H/SRR0/1 saved in a stack frame of a
684  * standard exception.
685  */
686 .macro EXCEPTION_RESTORE_REGS hsrr=0
687         /* Move original SRR0 and SRR1 into the respective regs */
688         ld      r9,_MSR(r1)
689         li      r10,0
690         .if \hsrr
691         mtspr   SPRN_HSRR1,r9
692         stb     r10,PACAHSRR_VALID(r13)
693         .else
694         mtspr   SPRN_SRR1,r9
695         stb     r10,PACASRR_VALID(r13)
696         .endif
697         ld      r9,_NIP(r1)
698         .if \hsrr
699         mtspr   SPRN_HSRR0,r9
700         .else
701         mtspr   SPRN_SRR0,r9
702         .endif
703         ld      r9,_CTR(r1)
704         mtctr   r9
705         ld      r9,_XER(r1)
706         mtxer   r9
707         ld      r9,_LINK(r1)
708         mtlr    r9
709         ld      r9,_CCR(r1)
710         mtcr    r9
711         SANITIZE_RESTORE_NVGPRS()
712         REST_GPRS(2, 13, r1)
713         REST_GPR(0, r1)
714         /* restore original r1. */
715         ld      r1,GPR1(r1)
716 .endm
717 
718 /*
719  * EARLY_BOOT_FIXUP - Fix real-mode interrupt with wrong endian in early boot.
720  *
721  * There's a short window during boot where although the kernel is running
722  * little endian, any exceptions will cause the CPU to switch back to big
723  * endian. For example a WARN() boils down to a trap instruction, which will
724  * cause a program check, and we end up here but with the CPU in big endian
725  * mode. The first instruction of the program check handler (in GEN_INT_ENTRY
726  * below) is an mtsprg, which when executed in the wrong endian is an lhzu with
727  * a ~3GB displacement from r3. The content of r3 is random, so that is a load
728  * from some random location, and depending on the system can easily lead to a
729  * checkstop, or an infinitely recursive page fault.
730  *
731  * So to handle that case we have a trampoline here that can detect we are in
732  * the wrong endian and flip us back to the correct endian. We can't flip
733  * MSR[LE] using mtmsr, so we have to use rfid. That requires backing up SRR0/1
734  * as well as a GPR. To do that we use SPRG0/2/3, as SPRG1 is already used for
735  * the paca. SPRG3 is user readable, but this trampoline is only active very
736  * early in boot, and SPRG3 will be reinitialised in vdso_getcpu_init() before
737  * userspace starts.
738  */
739 .macro EARLY_BOOT_FIXUP
740 BEGIN_FTR_SECTION
741 #ifdef CONFIG_CPU_LITTLE_ENDIAN
742         tdi   0,0,0x48    // Trap never, or in reverse endian: b . + 8
743         b     2f          // Skip trampoline if endian is correct
744         .long 0xa643707d  // mtsprg  0, r11      Backup r11
745         .long 0xa6027a7d  // mfsrr0  r11
746         .long 0xa643727d  // mtsprg  2, r11      Backup SRR0 in SPRG2
747         .long 0xa6027b7d  // mfsrr1  r11
748         .long 0xa643737d  // mtsprg  3, r11      Backup SRR1 in SPRG3
749         .long 0xa600607d  // mfmsr   r11
750         .long 0x01006b69  // xori    r11, r11, 1 Invert MSR[LE]
751         .long 0xa6037b7d  // mtsrr1  r11
752         /*
753          * This is 'li  r11,1f' where 1f is the absolute address of that
754          * label, byteswapped into the SI field of the instruction.
755          */
756         .long 0x00006039 | \
757                 ((ABS_ADDR(1f, real_vectors) & 0x00ff) << 24) | \
758                 ((ABS_ADDR(1f, real_vectors) & 0xff00) << 8)
759         .long 0xa6037a7d  // mtsrr0  r11
760         .long 0x2400004c  // rfid
761 1:
762         mfsprg r11, 3
763         mtsrr1 r11        // Restore SRR1
764         mfsprg r11, 2
765         mtsrr0 r11        // Restore SRR0
766         mfsprg r11, 0     // Restore r11
767 2:
768 #endif
769         /*
770          * program check could hit at any time, and pseries can not block
771          * MSR[ME] in early boot. So check if there is anything useful in r13
772          * yet, and spin forever if not.
773          */
774         mtsprg  0, r11
775         mfcr    r11
776         cmpdi   r13, 0
777         beq     .
778         mtcr    r11
779         mfsprg  r11, 0
780 END_FTR_SECTION(0, 1)     // nop out after boot
781 .endm
782 
783 /*
784  * There are a few constraints to be concerned with.
785  * - Real mode exceptions code/data must be located at their physical location.
786  * - Virtual mode exceptions must be mapped at their 0xc000... location.
787  * - Fixed location code must not call directly beyond the __end_interrupts
788  *   area when built with CONFIG_RELOCATABLE. LOAD_HANDLER / bctr sequence
789  *   must be used.
790  * - LOAD_HANDLER targets must be within first 64K of physical 0 /
791  *   virtual 0xc00...
792  * - Conditional branch targets must be within +/-32K of caller.
793  *
794  * "Virtual exceptions" run with relocation on (MSR_IR=1, MSR_DR=1), and
795  * therefore don't have to run in physically located code or rfid to
796  * virtual mode kernel code. However on relocatable kernels they do have
797  * to branch to KERNELBASE offset because the rest of the kernel (outside
798  * the exception vectors) may be located elsewhere.
799  *
800  * Virtual exceptions correspond with physical, except their entry points
801  * are offset by 0xc000000000000000 and also tend to get an added 0x4000
802  * offset applied. Virtual exceptions are enabled with the Alternate
803  * Interrupt Location (AIL) bit set in the LPCR. However this does not
804  * guarantee they will be delivered virtually. Some conditions (see the ISA)
805  * cause exceptions to be delivered in real mode.
806  *
807  * The scv instructions are a special case. They get a 0x3000 offset applied.
808  * scv exceptions have unique reentrancy properties, see below.
809  *
810  * It's impossible to receive interrupts below 0x300 via AIL.
811  *
812  * KVM: None of the virtual exceptions are from the guest. Anything that
813  * escalated to HV=1 from HV=0 is delivered via real mode handlers.
814  *
815  *
816  * We layout physical memory as follows:
817  * 0x0000 - 0x00ff : Secondary processor spin code
818  * 0x0100 - 0x18ff : Real mode pSeries interrupt vectors
819  * 0x1900 - 0x2fff : Real mode trampolines
820  * 0x3000 - 0x58ff : Relon (IR=1,DR=1) mode pSeries interrupt vectors
821  * 0x5900 - 0x6fff : Relon mode trampolines
822  * 0x7000 - 0x7fff : FWNMI data area
823  * 0x8000 -   .... : Common interrupt handlers, remaining early
824  *                   setup code, rest of kernel.
825  *
826  * We could reclaim 0x4000-0x42ff for real mode trampolines if the space
827  * is necessary. Until then it's more consistent to explicitly put VIRT_NONE
828  * vectors there.
829  */
830 OPEN_FIXED_SECTION(real_vectors,        0x0100, 0x1900)
831 OPEN_FIXED_SECTION(real_trampolines,    0x1900, 0x3000)
832 OPEN_FIXED_SECTION(virt_vectors,        0x3000, 0x5900)
833 OPEN_FIXED_SECTION(virt_trampolines,    0x5900, 0x7000)
834 
835 #ifdef CONFIG_PPC_POWERNV
836         .globl start_real_trampolines
837         .globl end_real_trampolines
838         .globl start_virt_trampolines
839         .globl end_virt_trampolines
840 #endif
841 
842 #if defined(CONFIG_PPC_PSERIES) || defined(CONFIG_PPC_POWERNV)
843 /*
844  * Data area reserved for FWNMI option.
845  * This address (0x7000) is fixed by the RPA.
846  * pseries and powernv need to keep the whole page from
847  * 0x7000 to 0x8000 free for use by the firmware
848  */
849 ZERO_FIXED_SECTION(fwnmi_page,          0x7000, 0x8000)
850 OPEN_TEXT_SECTION(0x8000)
851 #else
852 OPEN_TEXT_SECTION(0x7000)
853 #endif
854 
855 USE_FIXED_SECTION(real_vectors)
856 
857 /*
858  * This is the start of the interrupt handlers for pSeries
859  * This code runs with relocation off.
860  * Code from here to __end_interrupts gets copied down to real
861  * address 0x100 when we are running a relocatable kernel.
862  * Therefore any relative branches in this section must only
863  * branch to labels in this section.
864  */
865         .globl __start_interrupts
866 __start_interrupts:
867 
868 /**
869  * Interrupt 0x3000 - System Call Vectored Interrupt (syscall).
870  * This is a synchronous interrupt invoked with the "scv" instruction. The
871  * system call does not alter the HV bit, so it is directed to the OS.
872  *
873  * Handling:
874  * scv instructions enter the kernel without changing EE, RI, ME, or HV.
875  * In particular, this means we can take a maskable interrupt at any point
876  * in the scv handler, which is unlike any other interrupt. This is solved
877  * by treating the instruction addresses in the handler as being soft-masked,
878  * by adding a SOFT_MASK_TABLE entry for them.
879  *
880  * AIL-0 mode scv exceptions go to 0x17000-0x17fff, but we set AIL-3 and
881  * ensure scv is never executed with relocation off, which means AIL-0
882  * should never happen.
883  *
884  * Before leaving the following inside-__end_soft_masked text, at least of the
885  * following must be true:
886  * - MSR[PR]=1 (i.e., return to userspace)
887  * - MSR_EE|MSR_RI is clear (no reentrant exceptions)
888  * - Standard kernel environment is set up (stack, paca, etc)
889  *
890  * KVM:
891  * These interrupts do not elevate HV 0->1, so HV is not involved. PR KVM
892  * ensures that FSCR[SCV] is disabled whenever it has to force AIL off.
893  *
894  * Call convention:
895  *
896  * syscall register convention is in Documentation/arch/powerpc/syscall64-abi.rst
897  */
898 EXC_VIRT_BEGIN(system_call_vectored, 0x3000, 0x1000)
899         /* SCV 0 */
900         mr      r9,r13
901         GET_PACA(r13)
902         mflr    r11
903         mfctr   r12
904         li      r10,IRQS_ALL_DISABLED
905         stb     r10,PACAIRQSOFTMASK(r13)
906 #ifdef CONFIG_RELOCATABLE
907         b       system_call_vectored_tramp
908 #else
909         b       system_call_vectored_common
910 #endif
911         nop
912 
913         /* SCV 1 - 127 */
914         .rept   127
915         mr      r9,r13
916         GET_PACA(r13)
917         mflr    r11
918         mfctr   r12
919         li      r10,IRQS_ALL_DISABLED
920         stb     r10,PACAIRQSOFTMASK(r13)
921         li      r0,-1 /* cause failure */
922 #ifdef CONFIG_RELOCATABLE
923         b       system_call_vectored_sigill_tramp
924 #else
925         b       system_call_vectored_sigill
926 #endif
927         .endr
928 EXC_VIRT_END(system_call_vectored, 0x3000, 0x1000)
929 
930 // Treat scv vectors as soft-masked, see comment above.
931 // Use absolute values rather than labels here, so they don't get relocated,
932 // because this code runs unrelocated.
933 SOFT_MASK_TABLE(0xc000000000003000, 0xc000000000004000)
934 
935 #ifdef CONFIG_RELOCATABLE
936 TRAMP_VIRT_BEGIN(system_call_vectored_tramp)
937         __LOAD_HANDLER(r10, system_call_vectored_common, virt_trampolines)
938         mtctr   r10
939         bctr
940 
941 TRAMP_VIRT_BEGIN(system_call_vectored_sigill_tramp)
942         __LOAD_HANDLER(r10, system_call_vectored_sigill, virt_trampolines)
943         mtctr   r10
944         bctr
945 #endif
946 
947 
948 /* No virt vectors corresponding with 0x0..0x100 */
949 EXC_VIRT_NONE(0x4000, 0x100)
950 
951 
952 /**
953  * Interrupt 0x100 - System Reset Interrupt (SRESET aka NMI).
954  * This is a non-maskable, asynchronous interrupt always taken in real-mode.
955  * It is caused by:
956  * - Wake from power-saving state, on powernv.
957  * - An NMI from another CPU, triggered by firmware or hypercall.
958  * - As crash/debug signal injected from BMC, firmware or hypervisor.
959  *
960  * Handling:
961  * Power-save wakeup is the only performance critical path, so this is
962  * determined quickly as possible first. In this case volatile registers
963  * can be discarded and SPRs like CFAR don't need to be read.
964  *
965  * If not a powersave wakeup, then it's run as a regular interrupt, however
966  * it uses its own stack and PACA save area to preserve the regular kernel
967  * environment for debugging.
968  *
969  * This interrupt is not maskable, so triggering it when MSR[RI] is clear,
970  * or SCRATCH0 is in use, etc. may cause a crash. It's also not entirely
971  * correct to switch to virtual mode to run the regular interrupt handler
972  * because it might be interrupted when the MMU is in a bad state (e.g., SLB
973  * is clear).
974  *
975  * FWNMI:
976  * PAPR specifies a "fwnmi" facility which sends the sreset to a different
977  * entry point with a different register set up. Some hypervisors will
978  * send the sreset to 0x100 in the guest if it is not fwnmi capable.
979  *
980  * KVM:
981  * Unlike most SRR interrupts, this may be taken by the host while executing
982  * in a guest, so a KVM test is required. KVM will pull the CPU out of guest
983  * mode and then raise the sreset.
984  */
985 INT_DEFINE_BEGIN(system_reset)
986         IVEC=0x100
987         IAREA=PACA_EXNMI
988         IVIRT=0 /* no virt entry point */
989         ISTACK=0
990         IKVM_REAL=1
991 INT_DEFINE_END(system_reset)
992 
993 EXC_REAL_BEGIN(system_reset, 0x100, 0x100)
994 #ifdef CONFIG_PPC_P7_NAP
995         /*
996          * If running native on arch 2.06 or later, check if we are waking up
997          * from nap/sleep/winkle, and branch to idle handler. This tests SRR1
998          * bits 46:47. A non-0 value indicates that we are coming from a power
999          * saving state. The idle wakeup handler initially runs in real mode,
1000          * but we branch to the 0xc000... address so we can turn on relocation
1001          * with mtmsrd later, after SPRs are restored.
1002          *
1003          * Careful to minimise cost for the fast path (idle wakeup) while
1004          * also avoiding clobbering CFAR for the debug path (non-idle).
1005          *
1006          * For the idle wake case volatile registers can be clobbered, which
1007          * is why we use those initially. If it turns out to not be an idle
1008          * wake, carefully put everything back the way it was, so we can use
1009          * common exception macros to handle it.
1010          */
1011 BEGIN_FTR_SECTION
1012         SET_SCRATCH0(r13)
1013         GET_PACA(r13)
1014         std     r3,PACA_EXNMI+0*8(r13)
1015         std     r4,PACA_EXNMI+1*8(r13)
1016         std     r5,PACA_EXNMI+2*8(r13)
1017         mfspr   r3,SPRN_SRR1
1018         mfocrf  r4,0x80
1019         rlwinm. r5,r3,47-31,30,31
1020         bne+    system_reset_idle_wake
1021         /* Not powersave wakeup. Restore regs for regular interrupt handler. */
1022         mtocrf  0x80,r4
1023         ld      r3,PACA_EXNMI+0*8(r13)
1024         ld      r4,PACA_EXNMI+1*8(r13)
1025         ld      r5,PACA_EXNMI+2*8(r13)
1026         GET_SCRATCH0(r13)
1027 END_FTR_SECTION_IFSET(CPU_FTR_HVMODE | CPU_FTR_ARCH_206)
1028 #endif
1029 
1030         GEN_INT_ENTRY system_reset, virt=0
1031         /*
1032          * In theory, we should not enable relocation here if it was disabled
1033          * in SRR1, because the MMU may not be configured to support it (e.g.,
1034          * SLB may have been cleared). In practice, there should only be a few
1035          * small windows where that's the case, and sreset is considered to
1036          * be dangerous anyway.
1037          */
1038 EXC_REAL_END(system_reset, 0x100, 0x100)
1039 EXC_VIRT_NONE(0x4100, 0x100)
1040 
1041 #ifdef CONFIG_PPC_P7_NAP
1042 TRAMP_REAL_BEGIN(system_reset_idle_wake)
1043         /* We are waking up from idle, so may clobber any volatile register */
1044         cmpwi   cr1,r5,2
1045         bltlr   cr1     /* no state loss, return to idle caller with r3=SRR1 */
1046         __LOAD_FAR_HANDLER(r12, DOTSYM(idle_return_gpr_loss), real_trampolines)
1047         mtctr   r12
1048         bctr
1049 #endif
1050 
1051 #ifdef CONFIG_PPC_PSERIES
1052 /*
1053  * Vectors for the FWNMI option.  Share common code.
1054  */
1055 TRAMP_REAL_BEGIN(system_reset_fwnmi)
1056         GEN_INT_ENTRY system_reset, virt=0
1057 
1058 #endif /* CONFIG_PPC_PSERIES */
1059 
1060 EXC_COMMON_BEGIN(system_reset_common)
1061         __GEN_COMMON_ENTRY system_reset
1062         /*
1063          * Increment paca->in_nmi. When the interrupt entry wrapper later
1064          * enable MSR_RI, then SLB or MCE will be able to recover, but a nested
1065          * NMI will notice in_nmi and not recover because of the use of the NMI
1066          * stack. in_nmi reentrancy is tested in system_reset_exception.
1067          */
1068         lhz     r10,PACA_IN_NMI(r13)
1069         addi    r10,r10,1
1070         sth     r10,PACA_IN_NMI(r13)
1071 
1072         mr      r10,r1
1073         ld      r1,PACA_NMI_EMERG_SP(r13)
1074         subi    r1,r1,INT_FRAME_SIZE
1075         __GEN_COMMON_BODY system_reset
1076 
1077         addi    r3,r1,STACK_INT_FRAME_REGS
1078         bl      CFUNC(system_reset_exception)
1079 
1080         /* Clear MSR_RI before setting SRR0 and SRR1. */
1081         li      r9,0
1082         mtmsrd  r9,1
1083 
1084         /*
1085          * MSR_RI is clear, now we can decrement paca->in_nmi.
1086          */
1087         lhz     r10,PACA_IN_NMI(r13)
1088         subi    r10,r10,1
1089         sth     r10,PACA_IN_NMI(r13)
1090 
1091         kuap_kernel_restore r9, r10
1092         EXCEPTION_RESTORE_REGS
1093         RFI_TO_USER_OR_KERNEL
1094 
1095 
1096 /**
1097  * Interrupt 0x200 - Machine Check Interrupt (MCE).
1098  * This is a non-maskable interrupt always taken in real-mode. It can be
1099  * synchronous or asynchronous, caused by hardware or software, and it may be
1100  * taken in a power-saving state.
1101  *
1102  * Handling:
1103  * Similarly to system reset, this uses its own stack and PACA save area,
1104  * the difference is re-entrancy is allowed on the machine check stack.
1105  *
1106  * machine_check_early is run in real mode, and carefully decodes the
1107  * machine check and tries to handle it (e.g., flush the SLB if there was an
1108  * error detected there), determines if it was recoverable and logs the
1109  * event.
1110  *
1111  * This early code does not "reconcile" irq soft-mask state like SRESET or
1112  * regular interrupts do, so irqs_disabled() among other things may not work
1113  * properly (irq disable/enable already doesn't work because irq tracing can
1114  * not work in real mode).
1115  *
1116  * Then, depending on the execution context when the interrupt is taken, there
1117  * are 3 main actions:
1118  * - Executing in kernel mode. The event is queued with irq_work, which means
1119  *   it is handled when it is next safe to do so (i.e., the kernel has enabled
1120  *   interrupts), which could be immediately when the interrupt returns. This
1121  *   avoids nasty issues like switching to virtual mode when the MMU is in a
1122  *   bad state, or when executing OPAL code. (SRESET is exposed to such issues,
1123  *   but it has different priorities). Check to see if the CPU was in power
1124  *   save, and return via the wake up code if it was.
1125  *
1126  * - Executing in user mode. machine_check_exception is run like a normal
1127  *   interrupt handler, which processes the data generated by the early handler.
1128  *
1129  * - Executing in guest mode. The interrupt is run with its KVM test, and
1130  *   branches to KVM to deal with. KVM may queue the event for the host
1131  *   to report later.
1132  *
1133  * This interrupt is not maskable, so if it triggers when MSR[RI] is clear,
1134  * or SCRATCH0 is in use, it may cause a crash.
1135  *
1136  * KVM:
1137  * See SRESET.
1138  */
1139 INT_DEFINE_BEGIN(machine_check_early)
1140         IVEC=0x200
1141         IAREA=PACA_EXMC
1142         IVIRT=0 /* no virt entry point */
1143         IREALMODE_COMMON=1
1144         ISTACK=0
1145         IDAR=1
1146         IDSISR=1
1147         IKUAP=0 /* We don't touch AMR here, we never go to virtual mode */
1148 INT_DEFINE_END(machine_check_early)
1149 
1150 INT_DEFINE_BEGIN(machine_check)
1151         IVEC=0x200
1152         IAREA=PACA_EXMC
1153         IVIRT=0 /* no virt entry point */
1154         IDAR=1
1155         IDSISR=1
1156         IKVM_REAL=1
1157 INT_DEFINE_END(machine_check)
1158 
1159 EXC_REAL_BEGIN(machine_check, 0x200, 0x100)
1160         EARLY_BOOT_FIXUP
1161         GEN_INT_ENTRY machine_check_early, virt=0
1162 EXC_REAL_END(machine_check, 0x200, 0x100)
1163 EXC_VIRT_NONE(0x4200, 0x100)
1164 
1165 #ifdef CONFIG_PPC_PSERIES
1166 TRAMP_REAL_BEGIN(machine_check_fwnmi)
1167         /* See comment at machine_check exception, don't turn on RI */
1168         GEN_INT_ENTRY machine_check_early, virt=0
1169 #endif
1170 
1171 #define MACHINE_CHECK_HANDLER_WINDUP                    \
1172         /* Clear MSR_RI before setting SRR0 and SRR1. */\
1173         li      r9,0;                                   \
1174         mtmsrd  r9,1;           /* Clear MSR_RI */      \
1175         /* Decrement paca->in_mce now RI is clear. */   \
1176         lhz     r12,PACA_IN_MCE(r13);                   \
1177         subi    r12,r12,1;                              \
1178         sth     r12,PACA_IN_MCE(r13);                   \
1179         EXCEPTION_RESTORE_REGS
1180 
1181 EXC_COMMON_BEGIN(machine_check_early_common)
1182         __GEN_REALMODE_COMMON_ENTRY machine_check_early
1183 
1184         /*
1185          * Switch to mc_emergency stack and handle re-entrancy (we limit
1186          * the nested MCE upto level 4 to avoid stack overflow).
1187          * Save MCE registers srr1, srr0, dar and dsisr and then set ME=1
1188          *
1189          * We use paca->in_mce to check whether this is the first entry or
1190          * nested machine check. We increment paca->in_mce to track nested
1191          * machine checks.
1192          *
1193          * If this is the first entry then set stack pointer to
1194          * paca->mc_emergency_sp, otherwise r1 is already pointing to
1195          * stack frame on mc_emergency stack.
1196          *
1197          * NOTE: We are here with MSR_ME=0 (off), which means we risk a
1198          * checkstop if we get another machine check exception before we do
1199          * rfid with MSR_ME=1.
1200          *
1201          * This interrupt can wake directly from idle. If that is the case,
1202          * the machine check is handled then the idle wakeup code is called
1203          * to restore state.
1204          */
1205         lhz     r10,PACA_IN_MCE(r13)
1206         cmpwi   r10,0                   /* Are we in nested machine check */
1207         cmpwi   cr1,r10,MAX_MCE_DEPTH   /* Are we at maximum nesting */
1208         addi    r10,r10,1               /* increment paca->in_mce */
1209         sth     r10,PACA_IN_MCE(r13)
1210 
1211         mr      r10,r1                  /* Save r1 */
1212         bne     1f
1213         /* First machine check entry */
1214         ld      r1,PACAMCEMERGSP(r13)   /* Use MC emergency stack */
1215 1:      /* Limit nested MCE to level 4 to avoid stack overflow */
1216         bgt     cr1,unrecoverable_mce   /* Check if we hit limit of 4 */
1217         subi    r1,r1,INT_FRAME_SIZE    /* alloc stack frame */
1218 
1219         __GEN_COMMON_BODY machine_check_early
1220 
1221 BEGIN_FTR_SECTION
1222         bl      enable_machine_check
1223 END_FTR_SECTION_IFSET(CPU_FTR_HVMODE)
1224         addi    r3,r1,STACK_INT_FRAME_REGS
1225 BEGIN_FTR_SECTION
1226         bl      CFUNC(machine_check_early_boot)
1227 END_FTR_SECTION(0, 1)     // nop out after boot
1228         bl      CFUNC(machine_check_early)
1229         std     r3,RESULT(r1)   /* Save result */
1230         ld      r12,_MSR(r1)
1231 
1232 #ifdef CONFIG_PPC_P7_NAP
1233         /*
1234          * Check if thread was in power saving mode. We come here when any
1235          * of the following is true:
1236          * a. thread wasn't in power saving mode
1237          * b. thread was in power saving mode with no state loss,
1238          *    supervisor state loss or hypervisor state loss.
1239          *
1240          * Go back to nap/sleep/winkle mode again if (b) is true.
1241          */
1242 BEGIN_FTR_SECTION
1243         rlwinm. r11,r12,47-31,30,31
1244         bne     machine_check_idle_common
1245 END_FTR_SECTION_IFSET(CPU_FTR_HVMODE | CPU_FTR_ARCH_206)
1246 #endif
1247 
1248 #ifdef CONFIG_KVM_BOOK3S_64_HANDLER
1249         /*
1250          * Check if we are coming from guest. If yes, then run the normal
1251          * exception handler which will take the
1252          * machine_check_kvm->kvm_interrupt branch to deliver the MC event
1253          * to guest.
1254          */
1255         lbz     r11,HSTATE_IN_GUEST(r13)
1256         cmpwi   r11,0                   /* Check if coming from guest */
1257         bne     mce_deliver             /* continue if we are. */
1258 #endif
1259 
1260         /*
1261          * Check if we are coming from userspace. If yes, then run the normal
1262          * exception handler which will deliver the MC event to this kernel.
1263          */
1264         andi.   r11,r12,MSR_PR          /* See if coming from user. */
1265         bne     mce_deliver             /* continue in V mode if we are. */
1266 
1267         /*
1268          * At this point we are coming from kernel context.
1269          * Queue up the MCE event and return from the interrupt.
1270          * But before that, check if this is an un-recoverable exception.
1271          * If yes, then stay on emergency stack and panic.
1272          */
1273         andi.   r11,r12,MSR_RI
1274         beq     unrecoverable_mce
1275 
1276         /*
1277          * Check if we have successfully handled/recovered from error, if not
1278          * then stay on emergency stack and panic.
1279          */
1280         ld      r3,RESULT(r1)   /* Load result */
1281         cmpdi   r3,0            /* see if we handled MCE successfully */
1282         beq     unrecoverable_mce /* if !handled then panic */
1283 
1284         /*
1285          * Return from MC interrupt.
1286          * Queue up the MCE event so that we can log it later, while
1287          * returning from kernel or opal call.
1288          */
1289         bl      CFUNC(machine_check_queue_event)
1290         MACHINE_CHECK_HANDLER_WINDUP
1291         RFI_TO_KERNEL
1292 
1293 mce_deliver:
1294         /*
1295          * This is a host user or guest MCE. Restore all registers, then
1296          * run the "late" handler. For host user, this will run the
1297          * machine_check_exception handler in virtual mode like a normal
1298          * interrupt handler. For guest, this will trigger the KVM test
1299          * and branch to the KVM interrupt similarly to other interrupts.
1300          */
1301 BEGIN_FTR_SECTION
1302         ld      r10,ORIG_GPR3(r1)
1303         mtspr   SPRN_CFAR,r10
1304 END_FTR_SECTION_IFSET(CPU_FTR_CFAR)
1305         MACHINE_CHECK_HANDLER_WINDUP
1306         GEN_INT_ENTRY machine_check, virt=0
1307 
1308 EXC_COMMON_BEGIN(machine_check_common)
1309         /*
1310          * Machine check is different because we use a different
1311          * save area: PACA_EXMC instead of PACA_EXGEN.
1312          */
1313         GEN_COMMON machine_check
1314         addi    r3,r1,STACK_INT_FRAME_REGS
1315         bl      CFUNC(machine_check_exception_async)
1316         b       interrupt_return_srr
1317 
1318 
1319 #ifdef CONFIG_PPC_P7_NAP
1320 /*
1321  * This is an idle wakeup. Low level machine check has already been
1322  * done. Queue the event then call the idle code to do the wake up.
1323  */
1324 EXC_COMMON_BEGIN(machine_check_idle_common)
1325         bl      CFUNC(machine_check_queue_event)
1326 
1327         /*
1328          * GPR-loss wakeups are relatively straightforward, because the
1329          * idle sleep code has saved all non-volatile registers on its
1330          * own stack, and r1 in PACAR1.
1331          *
1332          * For no-loss wakeups the r1 and lr registers used by the
1333          * early machine check handler have to be restored first. r2 is
1334          * the kernel TOC, so no need to restore it.
1335          *
1336          * Then decrement MCE nesting after finishing with the stack.
1337          */
1338         ld      r3,_MSR(r1)
1339         ld      r4,_LINK(r1)
1340         ld      r1,GPR1(r1)
1341 
1342         lhz     r11,PACA_IN_MCE(r13)
1343         subi    r11,r11,1
1344         sth     r11,PACA_IN_MCE(r13)
1345 
1346         mtlr    r4
1347         rlwinm  r10,r3,47-31,30,31
1348         cmpwi   cr1,r10,2
1349         bltlr   cr1     /* no state loss, return to idle caller with r3=SRR1 */
1350         b       idle_return_gpr_loss
1351 #endif
1352 
1353 EXC_COMMON_BEGIN(unrecoverable_mce)
1354         /*
1355          * We are going down. But there are chances that we might get hit by
1356          * another MCE during panic path and we may run into unstable state
1357          * with no way out. Hence, turn ME bit off while going down, so that
1358          * when another MCE is hit during panic path, system will checkstop
1359          * and hypervisor will get restarted cleanly by SP.
1360          */
1361 BEGIN_FTR_SECTION
1362         li      r10,0 /* clear MSR_RI */
1363         mtmsrd  r10,1
1364         bl      CFUNC(disable_machine_check)
1365 END_FTR_SECTION_IFSET(CPU_FTR_HVMODE)
1366         ld      r10,PACAKMSR(r13)
1367         li      r3,MSR_ME
1368         andc    r10,r10,r3
1369         mtmsrd  r10
1370 
1371         lhz     r12,PACA_IN_MCE(r13)
1372         subi    r12,r12,1
1373         sth     r12,PACA_IN_MCE(r13)
1374 
1375         /*
1376          * Invoke machine_check_exception to print MCE event and panic.
1377          * This is the NMI version of the handler because we are called from
1378          * the early handler which is a true NMI.
1379          */
1380         addi    r3,r1,STACK_INT_FRAME_REGS
1381         bl      CFUNC(machine_check_exception)
1382 
1383         /*
1384          * We will not reach here. Even if we did, there is no way out.
1385          * Call unrecoverable_exception and die.
1386          */
1387         addi    r3,r1,STACK_INT_FRAME_REGS
1388         bl      CFUNC(unrecoverable_exception)
1389         b       .
1390 
1391 
1392 /**
1393  * Interrupt 0x300 - Data Storage Interrupt (DSI).
1394  * This is a synchronous interrupt generated due to a data access exception,
1395  * e.g., a load orstore which does not have a valid page table entry with
1396  * permissions. DAWR matches also fault here, as do RC updates, and minor misc
1397  * errors e.g., copy/paste, AMO, certain invalid CI accesses, etc.
1398  *
1399  * Handling:
1400  * - Hash MMU
1401  *   Go to do_hash_fault, which attempts to fill the HPT from an entry in the
1402  *   Linux page table. Hash faults can hit in kernel mode in a fairly
1403  *   arbitrary state (e.g., interrupts disabled, locks held) when accessing
1404  *   "non-bolted" regions, e.g., vmalloc space. However these should always be
1405  *   backed by Linux page table entries.
1406  *
1407  *   If no entry is found the Linux page fault handler is invoked (by
1408  *   do_hash_fault). Linux page faults can happen in kernel mode due to user
1409  *   copy operations of course.
1410  *
1411  *   KVM: The KVM HDSI handler may perform a load with MSR[DR]=1 in guest
1412  *   MMU context, which may cause a DSI in the host, which must go to the
1413  *   KVM handler. MSR[IR] is not enabled, so the real-mode handler will
1414  *   always be used regardless of AIL setting.
1415  *
1416  * - Radix MMU
1417  *   The hardware loads from the Linux page table directly, so a fault goes
1418  *   immediately to Linux page fault.
1419  *
1420  * Conditions like DAWR match are handled on the way in to Linux page fault.
1421  */
1422 INT_DEFINE_BEGIN(data_access)
1423         IVEC=0x300
1424         IDAR=1
1425         IDSISR=1
1426         IKVM_REAL=1
1427 INT_DEFINE_END(data_access)
1428 
1429 EXC_REAL_BEGIN(data_access, 0x300, 0x80)
1430         GEN_INT_ENTRY data_access, virt=0
1431 EXC_REAL_END(data_access, 0x300, 0x80)
1432 EXC_VIRT_BEGIN(data_access, 0x4300, 0x80)
1433         GEN_INT_ENTRY data_access, virt=1
1434 EXC_VIRT_END(data_access, 0x4300, 0x80)
1435 EXC_COMMON_BEGIN(data_access_common)
1436         GEN_COMMON data_access
1437         ld      r4,_DSISR(r1)
1438         addi    r3,r1,STACK_INT_FRAME_REGS
1439         andis.  r0,r4,DSISR_DABRMATCH@h
1440         bne-    1f
1441 #ifdef CONFIG_PPC_64S_HASH_MMU
1442 BEGIN_MMU_FTR_SECTION
1443         bl      CFUNC(do_hash_fault)
1444 MMU_FTR_SECTION_ELSE
1445         bl      CFUNC(do_page_fault)
1446 ALT_MMU_FTR_SECTION_END_IFCLR(MMU_FTR_TYPE_RADIX)
1447 #else
1448         bl      CFUNC(do_page_fault)
1449 #endif
1450         b       interrupt_return_srr
1451 
1452 1:      bl      CFUNC(do_break)
1453         /*
1454          * do_break() may have changed the NV GPRS while handling a breakpoint.
1455          * If so, we need to restore them with their updated values.
1456          */
1457         HANDLER_RESTORE_NVGPRS()
1458         b       interrupt_return_srr
1459 
1460 
1461 /**
1462  * Interrupt 0x380 - Data Segment Interrupt (DSLB).
1463  * This is a synchronous interrupt in response to an MMU fault missing SLB
1464  * entry for HPT, or an address outside RPT translation range.
1465  *
1466  * Handling:
1467  * - HPT:
1468  *   This refills the SLB, or reports an access fault similarly to a bad page
1469  *   fault. When coming from user-mode, the SLB handler may access any kernel
1470  *   data, though it may itself take a DSLB. When coming from kernel mode,
1471  *   recursive faults must be avoided so access is restricted to the kernel
1472  *   image text/data, kernel stack, and any data allocated below
1473  *   ppc64_bolted_size (first segment). The kernel handler must avoid stomping
1474  *   on user-handler data structures.
1475  *
1476  *   KVM: Same as 0x300, DSLB must test for KVM guest.
1477  */
1478 INT_DEFINE_BEGIN(data_access_slb)
1479         IVEC=0x380
1480         IDAR=1
1481         IKVM_REAL=1
1482 INT_DEFINE_END(data_access_slb)
1483 
1484 EXC_REAL_BEGIN(data_access_slb, 0x380, 0x80)
1485         GEN_INT_ENTRY data_access_slb, virt=0
1486 EXC_REAL_END(data_access_slb, 0x380, 0x80)
1487 EXC_VIRT_BEGIN(data_access_slb, 0x4380, 0x80)
1488         GEN_INT_ENTRY data_access_slb, virt=1
1489 EXC_VIRT_END(data_access_slb, 0x4380, 0x80)
1490 EXC_COMMON_BEGIN(data_access_slb_common)
1491         GEN_COMMON data_access_slb
1492 #ifdef CONFIG_PPC_64S_HASH_MMU
1493 BEGIN_MMU_FTR_SECTION
1494         /* HPT case, do SLB fault */
1495         addi    r3,r1,STACK_INT_FRAME_REGS
1496         bl      CFUNC(do_slb_fault)
1497         cmpdi   r3,0
1498         bne-    1f
1499         b       fast_interrupt_return_srr
1500 1:      /* Error case */
1501 MMU_FTR_SECTION_ELSE
1502         /* Radix case, access is outside page table range */
1503         li      r3,-EFAULT
1504 ALT_MMU_FTR_SECTION_END_IFCLR(MMU_FTR_TYPE_RADIX)
1505 #else
1506         li      r3,-EFAULT
1507 #endif
1508         std     r3,RESULT(r1)
1509         addi    r3,r1,STACK_INT_FRAME_REGS
1510         bl      CFUNC(do_bad_segment_interrupt)
1511         b       interrupt_return_srr
1512 
1513 
1514 /**
1515  * Interrupt 0x400 - Instruction Storage Interrupt (ISI).
1516  * This is a synchronous interrupt in response to an MMU fault due to an
1517  * instruction fetch.
1518  *
1519  * Handling:
1520  * Similar to DSI, though in response to fetch. The faulting address is found
1521  * in SRR0 (rather than DAR), and status in SRR1 (rather than DSISR).
1522  */
1523 INT_DEFINE_BEGIN(instruction_access)
1524         IVEC=0x400
1525         IISIDE=1
1526         IDAR=1
1527         IDSISR=1
1528 #ifdef CONFIG_KVM_BOOK3S_PR_POSSIBLE
1529         IKVM_REAL=1
1530 #endif
1531 INT_DEFINE_END(instruction_access)
1532 
1533 EXC_REAL_BEGIN(instruction_access, 0x400, 0x80)
1534         GEN_INT_ENTRY instruction_access, virt=0
1535 EXC_REAL_END(instruction_access, 0x400, 0x80)
1536 EXC_VIRT_BEGIN(instruction_access, 0x4400, 0x80)
1537         GEN_INT_ENTRY instruction_access, virt=1
1538 EXC_VIRT_END(instruction_access, 0x4400, 0x80)
1539 EXC_COMMON_BEGIN(instruction_access_common)
1540         GEN_COMMON instruction_access
1541         addi    r3,r1,STACK_INT_FRAME_REGS
1542 #ifdef CONFIG_PPC_64S_HASH_MMU
1543 BEGIN_MMU_FTR_SECTION
1544         bl      CFUNC(do_hash_fault)
1545 MMU_FTR_SECTION_ELSE
1546         bl      CFUNC(do_page_fault)
1547 ALT_MMU_FTR_SECTION_END_IFCLR(MMU_FTR_TYPE_RADIX)
1548 #else
1549         bl      CFUNC(do_page_fault)
1550 #endif
1551         b       interrupt_return_srr
1552 
1553 
1554 /**
1555  * Interrupt 0x480 - Instruction Segment Interrupt (ISLB).
1556  * This is a synchronous interrupt in response to an MMU fault due to an
1557  * instruction fetch.
1558  *
1559  * Handling:
1560  * Similar to DSLB, though in response to fetch. The faulting address is found
1561  * in SRR0 (rather than DAR).
1562  */
1563 INT_DEFINE_BEGIN(instruction_access_slb)
1564         IVEC=0x480
1565         IISIDE=1
1566         IDAR=1
1567 #ifdef CONFIG_KVM_BOOK3S_PR_POSSIBLE
1568         IKVM_REAL=1
1569 #endif
1570 INT_DEFINE_END(instruction_access_slb)
1571 
1572 EXC_REAL_BEGIN(instruction_access_slb, 0x480, 0x80)
1573         GEN_INT_ENTRY instruction_access_slb, virt=0
1574 EXC_REAL_END(instruction_access_slb, 0x480, 0x80)
1575 EXC_VIRT_BEGIN(instruction_access_slb, 0x4480, 0x80)
1576         GEN_INT_ENTRY instruction_access_slb, virt=1
1577 EXC_VIRT_END(instruction_access_slb, 0x4480, 0x80)
1578 EXC_COMMON_BEGIN(instruction_access_slb_common)
1579         GEN_COMMON instruction_access_slb
1580 #ifdef CONFIG_PPC_64S_HASH_MMU
1581 BEGIN_MMU_FTR_SECTION
1582         /* HPT case, do SLB fault */
1583         addi    r3,r1,STACK_INT_FRAME_REGS
1584         bl      CFUNC(do_slb_fault)
1585         cmpdi   r3,0
1586         bne-    1f
1587         b       fast_interrupt_return_srr
1588 1:      /* Error case */
1589 MMU_FTR_SECTION_ELSE
1590         /* Radix case, access is outside page table range */
1591         li      r3,-EFAULT
1592 ALT_MMU_FTR_SECTION_END_IFCLR(MMU_FTR_TYPE_RADIX)
1593 #else
1594         li      r3,-EFAULT
1595 #endif
1596         std     r3,RESULT(r1)
1597         addi    r3,r1,STACK_INT_FRAME_REGS
1598         bl      CFUNC(do_bad_segment_interrupt)
1599         b       interrupt_return_srr
1600 
1601 
1602 /**
1603  * Interrupt 0x500 - External Interrupt.
1604  * This is an asynchronous maskable interrupt in response to an "external
1605  * exception" from the interrupt controller or hypervisor (e.g., device
1606  * interrupt). It is maskable in hardware by clearing MSR[EE], and
1607  * soft-maskable with IRQS_DISABLED mask (i.e., local_irq_disable()).
1608  *
1609  * When running in HV mode, Linux sets up the LPCR[LPES] bit such that
1610  * interrupts are delivered with HSRR registers, guests use SRRs, which
1611  * reqiures IHSRR_IF_HVMODE.
1612  *
1613  * On bare metal POWER9 and later, Linux sets the LPCR[HVICE] bit such that
1614  * external interrupts are delivered as Hypervisor Virtualization Interrupts
1615  * rather than External Interrupts.
1616  *
1617  * Handling:
1618  * This calls into Linux IRQ handler. NVGPRs are not saved to reduce overhead,
1619  * because registers at the time of the interrupt are not so important as it is
1620  * asynchronous.
1621  *
1622  * If soft masked, the masked handler will note the pending interrupt for
1623  * replay, and clear MSR[EE] in the interrupted context.
1624  *
1625  * CFAR is not required because this is an asynchronous interrupt that in
1626  * general won't have much bearing on the state of the CPU, with the possible
1627  * exception of crash/debug IPIs, but those are generally moving to use SRESET
1628  * IPIs. Unless this is an HV interrupt and KVM HV is possible, in which case
1629  * it may be exiting the guest and need CFAR to be saved.
1630  */
1631 INT_DEFINE_BEGIN(hardware_interrupt)
1632         IVEC=0x500
1633         IHSRR_IF_HVMODE=1
1634         IMASK=IRQS_DISABLED
1635         IKVM_REAL=1
1636         IKVM_VIRT=1
1637         ICFAR=0
1638 #ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
1639         ICFAR_IF_HVMODE=1
1640 #endif
1641 INT_DEFINE_END(hardware_interrupt)
1642 
1643 EXC_REAL_BEGIN(hardware_interrupt, 0x500, 0x100)
1644         GEN_INT_ENTRY hardware_interrupt, virt=0
1645 EXC_REAL_END(hardware_interrupt, 0x500, 0x100)
1646 EXC_VIRT_BEGIN(hardware_interrupt, 0x4500, 0x100)
1647         GEN_INT_ENTRY hardware_interrupt, virt=1
1648 EXC_VIRT_END(hardware_interrupt, 0x4500, 0x100)
1649 EXC_COMMON_BEGIN(hardware_interrupt_common)
1650         GEN_COMMON hardware_interrupt
1651         addi    r3,r1,STACK_INT_FRAME_REGS
1652         bl      CFUNC(do_IRQ)
1653         BEGIN_FTR_SECTION
1654         b       interrupt_return_hsrr
1655         FTR_SECTION_ELSE
1656         b       interrupt_return_srr
1657         ALT_FTR_SECTION_END_IFSET(CPU_FTR_HVMODE | CPU_FTR_ARCH_206)
1658 
1659 
1660 /**
1661  * Interrupt 0x600 - Alignment Interrupt
1662  * This is a synchronous interrupt in response to data alignment fault.
1663  */
1664 INT_DEFINE_BEGIN(alignment)
1665         IVEC=0x600
1666         IDAR=1
1667         IDSISR=1
1668 #ifdef CONFIG_KVM_BOOK3S_PR_POSSIBLE
1669         IKVM_REAL=1
1670 #endif
1671 INT_DEFINE_END(alignment)
1672 
1673 EXC_REAL_BEGIN(alignment, 0x600, 0x100)
1674         GEN_INT_ENTRY alignment, virt=0
1675 EXC_REAL_END(alignment, 0x600, 0x100)
1676 EXC_VIRT_BEGIN(alignment, 0x4600, 0x100)
1677         GEN_INT_ENTRY alignment, virt=1
1678 EXC_VIRT_END(alignment, 0x4600, 0x100)
1679 EXC_COMMON_BEGIN(alignment_common)
1680         GEN_COMMON alignment
1681         addi    r3,r1,STACK_INT_FRAME_REGS
1682         bl      CFUNC(alignment_exception)
1683         HANDLER_RESTORE_NVGPRS() /* instruction emulation may change GPRs */
1684         b       interrupt_return_srr
1685 
1686 
1687 /**
1688  * Interrupt 0x700 - Program Interrupt (program check).
1689  * This is a synchronous interrupt in response to various instruction faults:
1690  * traps, privilege errors, TM errors, floating point exceptions.
1691  *
1692  * Handling:
1693  * This interrupt may use the "emergency stack" in some cases when being taken
1694  * from kernel context, which complicates handling.
1695  */
1696 INT_DEFINE_BEGIN(program_check)
1697         IVEC=0x700
1698 #ifdef CONFIG_KVM_BOOK3S_PR_POSSIBLE
1699         IKVM_REAL=1
1700 #endif
1701 INT_DEFINE_END(program_check)
1702 
1703 EXC_REAL_BEGIN(program_check, 0x700, 0x100)
1704         EARLY_BOOT_FIXUP
1705         GEN_INT_ENTRY program_check, virt=0
1706 EXC_REAL_END(program_check, 0x700, 0x100)
1707 EXC_VIRT_BEGIN(program_check, 0x4700, 0x100)
1708         GEN_INT_ENTRY program_check, virt=1
1709 EXC_VIRT_END(program_check, 0x4700, 0x100)
1710 EXC_COMMON_BEGIN(program_check_common)
1711         __GEN_COMMON_ENTRY program_check
1712 
1713         /*
1714          * It's possible to receive a TM Bad Thing type program check with
1715          * userspace register values (in particular r1), but with SRR1 reporting
1716          * that we came from the kernel. Normally that would confuse the bad
1717          * stack logic, and we would report a bad kernel stack pointer. Instead
1718          * we switch to the emergency stack if we're taking a TM Bad Thing from
1719          * the kernel.
1720          */
1721 
1722         andi.   r10,r12,MSR_PR
1723         bne     .Lnormal_stack          /* If userspace, go normal path */
1724 
1725         andis.  r10,r12,(SRR1_PROGTM)@h
1726         bne     .Lemergency_stack       /* If TM, emergency             */
1727 
1728         cmpdi   r1,-INT_FRAME_SIZE      /* check if r1 is in userspace  */
1729         blt     .Lnormal_stack          /* normal path if not           */
1730 
1731         /* Use the emergency stack                                      */
1732 .Lemergency_stack:
1733         andi.   r10,r12,MSR_PR          /* Set CR0 correctly for label  */
1734                                         /* 3 in EXCEPTION_PROLOG_COMMON */
1735         mr      r10,r1                  /* Save r1                      */
1736         ld      r1,PACAEMERGSP(r13)     /* Use emergency stack          */
1737         subi    r1,r1,INT_FRAME_SIZE    /* alloc stack frame            */
1738         __ISTACK(program_check)=0
1739         __GEN_COMMON_BODY program_check
1740         b .Ldo_program_check
1741 
1742 .Lnormal_stack:
1743         __ISTACK(program_check)=1
1744         __GEN_COMMON_BODY program_check
1745 
1746 .Ldo_program_check:
1747         addi    r3,r1,STACK_INT_FRAME_REGS
1748         bl      CFUNC(program_check_exception)
1749         HANDLER_RESTORE_NVGPRS() /* instruction emulation may change GPRs */
1750         b       interrupt_return_srr
1751 
1752 
1753 /*
1754  * Interrupt 0x800 - Floating-Point Unavailable Interrupt.
1755  * This is a synchronous interrupt in response to executing an fp instruction
1756  * with MSR[FP]=0.
1757  *
1758  * Handling:
1759  * This will load FP registers and enable the FP bit if coming from userspace,
1760  * otherwise report a bad kernel use of FP.
1761  */
1762 INT_DEFINE_BEGIN(fp_unavailable)
1763         IVEC=0x800
1764 #ifdef CONFIG_KVM_BOOK3S_PR_POSSIBLE
1765         IKVM_REAL=1
1766 #endif
1767         IMSR_R12=1
1768 INT_DEFINE_END(fp_unavailable)
1769 
1770 EXC_REAL_BEGIN(fp_unavailable, 0x800, 0x100)
1771         GEN_INT_ENTRY fp_unavailable, virt=0
1772 EXC_REAL_END(fp_unavailable, 0x800, 0x100)
1773 EXC_VIRT_BEGIN(fp_unavailable, 0x4800, 0x100)
1774         GEN_INT_ENTRY fp_unavailable, virt=1
1775 EXC_VIRT_END(fp_unavailable, 0x4800, 0x100)
1776 EXC_COMMON_BEGIN(fp_unavailable_common)
1777         GEN_COMMON fp_unavailable
1778         bne     1f                      /* if from user, just load it up */
1779         addi    r3,r1,STACK_INT_FRAME_REGS
1780         bl      CFUNC(kernel_fp_unavailable_exception)
1781 0:      trap
1782         EMIT_BUG_ENTRY 0b, __FILE__, __LINE__, 0
1783 1:
1784 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1785 BEGIN_FTR_SECTION
1786         /* Test if 2 TM state bits are zero.  If non-zero (ie. userspace was in
1787          * transaction), go do TM stuff
1788          */
1789         rldicl. r0, r12, (64-MSR_TS_LG), (64-2)
1790         bne-    2f
1791 END_FTR_SECTION_IFSET(CPU_FTR_TM)
1792 #endif
1793         bl      CFUNC(load_up_fpu)
1794         b       fast_interrupt_return_srr
1795 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1796 2:      /* User process was in a transaction */
1797         addi    r3,r1,STACK_INT_FRAME_REGS
1798         bl      CFUNC(fp_unavailable_tm)
1799         b       interrupt_return_srr
1800 #endif
1801 
1802 
1803 /**
1804  * Interrupt 0x900 - Decrementer Interrupt.
1805  * This is an asynchronous interrupt in response to a decrementer exception
1806  * (e.g., DEC has wrapped below zero). It is maskable in hardware by clearing
1807  * MSR[EE], and soft-maskable with IRQS_DISABLED mask (i.e.,
1808  * local_irq_disable()).
1809  *
1810  * Handling:
1811  * This calls into Linux timer handler. NVGPRs are not saved (see 0x500).
1812  *
1813  * If soft masked, the masked handler will note the pending interrupt for
1814  * replay, and bump the decrementer to a high value, leaving MSR[EE] enabled
1815  * in the interrupted context.
1816  * If PPC_WATCHDOG is configured, the soft masked handler will actually set
1817  * things back up to run soft_nmi_interrupt as a regular interrupt handler
1818  * on the emergency stack.
1819  *
1820  * CFAR is not required because this is asynchronous (see hardware_interrupt).
1821  * A watchdog interrupt may like to have CFAR, but usually the interesting
1822  * branch is long gone by that point (e.g., infinite loop).
1823  */
1824 INT_DEFINE_BEGIN(decrementer)
1825         IVEC=0x900
1826         IMASK=IRQS_DISABLED
1827 #ifdef CONFIG_KVM_BOOK3S_PR_POSSIBLE
1828         IKVM_REAL=1
1829 #endif
1830         ICFAR=0
1831 INT_DEFINE_END(decrementer)
1832 
1833 EXC_REAL_BEGIN(decrementer, 0x900, 0x80)
1834         GEN_INT_ENTRY decrementer, virt=0
1835 EXC_REAL_END(decrementer, 0x900, 0x80)
1836 EXC_VIRT_BEGIN(decrementer, 0x4900, 0x80)
1837         GEN_INT_ENTRY decrementer, virt=1
1838 EXC_VIRT_END(decrementer, 0x4900, 0x80)
1839 EXC_COMMON_BEGIN(decrementer_common)
1840         GEN_COMMON decrementer
1841         addi    r3,r1,STACK_INT_FRAME_REGS
1842         bl      CFUNC(timer_interrupt)
1843         b       interrupt_return_srr
1844 
1845 
1846 /**
1847  * Interrupt 0x980 - Hypervisor Decrementer Interrupt.
1848  * This is an asynchronous interrupt, similar to 0x900 but for the HDEC
1849  * register.
1850  *
1851  * Handling:
1852  * Linux does not use this outside KVM where it's used to keep a host timer
1853  * while the guest is given control of DEC. It should normally be caught by
1854  * the KVM test and routed there.
1855  */
1856 INT_DEFINE_BEGIN(hdecrementer)
1857         IVEC=0x980
1858         IHSRR=1
1859         ISTACK=0
1860         IKVM_REAL=1
1861         IKVM_VIRT=1
1862 INT_DEFINE_END(hdecrementer)
1863 
1864 EXC_REAL_BEGIN(hdecrementer, 0x980, 0x80)
1865         GEN_INT_ENTRY hdecrementer, virt=0
1866 EXC_REAL_END(hdecrementer, 0x980, 0x80)
1867 EXC_VIRT_BEGIN(hdecrementer, 0x4980, 0x80)
1868         GEN_INT_ENTRY hdecrementer, virt=1
1869 EXC_VIRT_END(hdecrementer, 0x4980, 0x80)
1870 EXC_COMMON_BEGIN(hdecrementer_common)
1871         __GEN_COMMON_ENTRY hdecrementer
1872         /*
1873          * Hypervisor decrementer interrupts not caught by the KVM test
1874          * shouldn't occur but are sometimes left pending on exit from a KVM
1875          * guest.  We don't need to do anything to clear them, as they are
1876          * edge-triggered.
1877          *
1878          * Be careful to avoid touching the kernel stack.
1879          */
1880         li      r10,0
1881         stb     r10,PACAHSRR_VALID(r13)
1882         ld      r10,PACA_EXGEN+EX_CTR(r13)
1883         mtctr   r10
1884         mtcrf   0x80,r9
1885         ld      r9,PACA_EXGEN+EX_R9(r13)
1886         ld      r10,PACA_EXGEN+EX_R10(r13)
1887         ld      r11,PACA_EXGEN+EX_R11(r13)
1888         ld      r12,PACA_EXGEN+EX_R12(r13)
1889         ld      r13,PACA_EXGEN+EX_R13(r13)
1890         HRFI_TO_KERNEL
1891 
1892 
1893 /**
1894  * Interrupt 0xa00 - Directed Privileged Doorbell Interrupt.
1895  * This is an asynchronous interrupt in response to a msgsndp doorbell.
1896  * It is maskable in hardware by clearing MSR[EE], and soft-maskable with
1897  * IRQS_DISABLED mask (i.e., local_irq_disable()).
1898  *
1899  * Handling:
1900  * Guests may use this for IPIs between threads in a core if the
1901  * hypervisor supports it. NVGPRS are not saved (see 0x500).
1902  *
1903  * If soft masked, the masked handler will note the pending interrupt for
1904  * replay, leaving MSR[EE] enabled in the interrupted context because the
1905  * doorbells are edge triggered.
1906  *
1907  * CFAR is not required, similarly to hardware_interrupt.
1908  */
1909 INT_DEFINE_BEGIN(doorbell_super)
1910         IVEC=0xa00
1911         IMASK=IRQS_DISABLED
1912 #ifdef CONFIG_KVM_BOOK3S_PR_POSSIBLE
1913         IKVM_REAL=1
1914 #endif
1915         ICFAR=0
1916 INT_DEFINE_END(doorbell_super)
1917 
1918 EXC_REAL_BEGIN(doorbell_super, 0xa00, 0x100)
1919         GEN_INT_ENTRY doorbell_super, virt=0
1920 EXC_REAL_END(doorbell_super, 0xa00, 0x100)
1921 EXC_VIRT_BEGIN(doorbell_super, 0x4a00, 0x100)
1922         GEN_INT_ENTRY doorbell_super, virt=1
1923 EXC_VIRT_END(doorbell_super, 0x4a00, 0x100)
1924 EXC_COMMON_BEGIN(doorbell_super_common)
1925         GEN_COMMON doorbell_super
1926         addi    r3,r1,STACK_INT_FRAME_REGS
1927 #ifdef CONFIG_PPC_DOORBELL
1928         bl      CFUNC(doorbell_exception)
1929 #else
1930         bl      CFUNC(unknown_async_exception)
1931 #endif
1932         b       interrupt_return_srr
1933 
1934 
1935 EXC_REAL_NONE(0xb00, 0x100)
1936 EXC_VIRT_NONE(0x4b00, 0x100)
1937 
1938 /**
1939  * Interrupt 0xc00 - System Call Interrupt (syscall, hcall).
1940  * This is a synchronous interrupt invoked with the "sc" instruction. The
1941  * system call is invoked with "sc 0" and does not alter the HV bit, so it
1942  * is directed to the currently running OS. The hypercall is invoked with
1943  * "sc 1" and it sets HV=1, so it elevates to hypervisor.
1944  *
1945  * In HPT, sc 1 always goes to 0xc00 real mode. In RADIX, sc 1 can go to
1946  * 0x4c00 virtual mode.
1947  *
1948  * Handling:
1949  * If the KVM test fires then it was due to a hypercall and is accordingly
1950  * routed to KVM. Otherwise this executes a normal Linux system call.
1951  *
1952  * Call convention:
1953  *
1954  * syscall and hypercalls register conventions are documented in
1955  * Documentation/arch/powerpc/syscall64-abi.rst and
1956  * Documentation/arch/powerpc/papr_hcalls.rst respectively.
1957  *
1958  * The intersection of volatile registers that don't contain possible
1959  * inputs is: cr0, xer, ctr. We may use these as scratch regs upon entry
1960  * without saving, though xer is not a good idea to use, as hardware may
1961  * interpret some bits so it may be costly to change them.
1962  */
1963 INT_DEFINE_BEGIN(system_call)
1964         IVEC=0xc00
1965         IKVM_REAL=1
1966         IKVM_VIRT=1
1967         ICFAR=0
1968 INT_DEFINE_END(system_call)
1969 
1970 .macro SYSTEM_CALL virt
1971 #ifdef CONFIG_KVM_BOOK3S_64_HANDLER
1972         /*
1973          * There is a little bit of juggling to get syscall and hcall
1974          * working well. Save r13 in ctr to avoid using SPRG scratch
1975          * register.
1976          *
1977          * Userspace syscalls have already saved the PPR, hcalls must save
1978          * it before setting HMT_MEDIUM.
1979          */
1980         mtctr   r13
1981         GET_PACA(r13)
1982         std     r10,PACA_EXGEN+EX_R10(r13)
1983         INTERRUPT_TO_KERNEL
1984         KVMTEST system_call kvm_hcall /* uses r10, branch to kvm_hcall */
1985         mfctr   r9
1986 #else
1987         mr      r9,r13
1988         GET_PACA(r13)
1989         INTERRUPT_TO_KERNEL
1990 #endif
1991 
1992         /* We reach here with PACA in r13, r13 in r9. */
1993         mfspr   r11,SPRN_SRR0
1994         mfspr   r12,SPRN_SRR1
1995 
1996         HMT_MEDIUM
1997 
1998         .if ! \virt
1999         __LOAD_HANDLER(r10, system_call_common_real, real_vectors)
2000         mtctr   r10
2001         bctr
2002         .else
2003 #ifdef CONFIG_RELOCATABLE
2004         __LOAD_HANDLER(r10, system_call_common, virt_vectors)
2005         mtctr   r10
2006         bctr
2007 #else
2008         b       system_call_common
2009 #endif
2010         .endif
2011 .endm
2012 
2013 EXC_REAL_BEGIN(system_call, 0xc00, 0x100)
2014         SYSTEM_CALL 0
2015 EXC_REAL_END(system_call, 0xc00, 0x100)
2016 EXC_VIRT_BEGIN(system_call, 0x4c00, 0x100)
2017         SYSTEM_CALL 1
2018 EXC_VIRT_END(system_call, 0x4c00, 0x100)
2019 
2020 #ifdef CONFIG_KVM_BOOK3S_64_HANDLER
2021 TRAMP_REAL_BEGIN(kvm_hcall)
2022         std     r9,PACA_EXGEN+EX_R9(r13)
2023         std     r11,PACA_EXGEN+EX_R11(r13)
2024         std     r12,PACA_EXGEN+EX_R12(r13)
2025         mfcr    r9
2026         mfctr   r10
2027         std     r10,PACA_EXGEN+EX_R13(r13)
2028         li      r10,0
2029         std     r10,PACA_EXGEN+EX_CFAR(r13)
2030         std     r10,PACA_EXGEN+EX_CTR(r13)
2031          /*
2032           * Save the PPR (on systems that support it) before changing to
2033           * HMT_MEDIUM. That allows the KVM code to save that value into the
2034           * guest state (it is the guest's PPR value).
2035           */
2036 BEGIN_FTR_SECTION
2037         mfspr   r10,SPRN_PPR
2038         std     r10,PACA_EXGEN+EX_PPR(r13)
2039 END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
2040 
2041         HMT_MEDIUM
2042 
2043 #ifdef CONFIG_RELOCATABLE
2044         /*
2045          * Requires __LOAD_FAR_HANDLER beause kvmppc_hcall lives
2046          * outside the head section.
2047          */
2048         __LOAD_FAR_HANDLER(r10, kvmppc_hcall, real_trampolines)
2049         mtctr   r10
2050         bctr
2051 #else
2052         b       kvmppc_hcall
2053 #endif
2054 #endif
2055 
2056 /**
2057  * Interrupt 0xd00 - Trace Interrupt.
2058  * This is a synchronous interrupt in response to instruction step or
2059  * breakpoint faults.
2060  */
2061 INT_DEFINE_BEGIN(single_step)
2062         IVEC=0xd00
2063 #ifdef CONFIG_KVM_BOOK3S_PR_POSSIBLE
2064         IKVM_REAL=1
2065 #endif
2066 INT_DEFINE_END(single_step)
2067 
2068 EXC_REAL_BEGIN(single_step, 0xd00, 0x100)
2069         GEN_INT_ENTRY single_step, virt=0
2070 EXC_REAL_END(single_step, 0xd00, 0x100)
2071 EXC_VIRT_BEGIN(single_step, 0x4d00, 0x100)
2072         GEN_INT_ENTRY single_step, virt=1
2073 EXC_VIRT_END(single_step, 0x4d00, 0x100)
2074 EXC_COMMON_BEGIN(single_step_common)
2075         GEN_COMMON single_step
2076         addi    r3,r1,STACK_INT_FRAME_REGS
2077         bl      CFUNC(single_step_exception)
2078         b       interrupt_return_srr
2079 
2080 
2081 /**
2082  * Interrupt 0xe00 - Hypervisor Data Storage Interrupt (HDSI).
2083  * This is a synchronous interrupt in response to an MMU fault caused by a
2084  * guest data access.
2085  *
2086  * Handling:
2087  * This should always get routed to KVM. In radix MMU mode, this is caused
2088  * by a guest nested radix access that can't be performed due to the
2089  * partition scope page table. In hash mode, this can be caused by guests
2090  * running with translation disabled (virtual real mode) or with VPM enabled.
2091  * KVM will update the page table structures or disallow the access.
2092  */
2093 INT_DEFINE_BEGIN(h_data_storage)
2094         IVEC=0xe00
2095         IHSRR=1
2096         IDAR=1
2097         IDSISR=1
2098         IKVM_REAL=1
2099         IKVM_VIRT=1
2100 INT_DEFINE_END(h_data_storage)
2101 
2102 EXC_REAL_BEGIN(h_data_storage, 0xe00, 0x20)
2103         GEN_INT_ENTRY h_data_storage, virt=0, ool=1
2104 EXC_REAL_END(h_data_storage, 0xe00, 0x20)
2105 EXC_VIRT_BEGIN(h_data_storage, 0x4e00, 0x20)
2106         GEN_INT_ENTRY h_data_storage, virt=1, ool=1
2107 EXC_VIRT_END(h_data_storage, 0x4e00, 0x20)
2108 EXC_COMMON_BEGIN(h_data_storage_common)
2109         GEN_COMMON h_data_storage
2110         addi    r3,r1,STACK_INT_FRAME_REGS
2111 BEGIN_MMU_FTR_SECTION
2112         bl      CFUNC(do_bad_page_fault_segv)
2113 MMU_FTR_SECTION_ELSE
2114         bl      CFUNC(unknown_exception)
2115 ALT_MMU_FTR_SECTION_END_IFSET(MMU_FTR_TYPE_RADIX)
2116         b       interrupt_return_hsrr
2117 
2118 
2119 /**
2120  * Interrupt 0xe20 - Hypervisor Instruction Storage Interrupt (HISI).
2121  * This is a synchronous interrupt in response to an MMU fault caused by a
2122  * guest instruction fetch, similar to HDSI.
2123  */
2124 INT_DEFINE_BEGIN(h_instr_storage)
2125         IVEC=0xe20
2126         IHSRR=1
2127         IKVM_REAL=1
2128         IKVM_VIRT=1
2129 INT_DEFINE_END(h_instr_storage)
2130 
2131 EXC_REAL_BEGIN(h_instr_storage, 0xe20, 0x20)
2132         GEN_INT_ENTRY h_instr_storage, virt=0, ool=1
2133 EXC_REAL_END(h_instr_storage, 0xe20, 0x20)
2134 EXC_VIRT_BEGIN(h_instr_storage, 0x4e20, 0x20)
2135         GEN_INT_ENTRY h_instr_storage, virt=1, ool=1
2136 EXC_VIRT_END(h_instr_storage, 0x4e20, 0x20)
2137 EXC_COMMON_BEGIN(h_instr_storage_common)
2138         GEN_COMMON h_instr_storage
2139         addi    r3,r1,STACK_INT_FRAME_REGS
2140         bl      CFUNC(unknown_exception)
2141         b       interrupt_return_hsrr
2142 
2143 
2144 /**
2145  * Interrupt 0xe40 - Hypervisor Emulation Assistance Interrupt.
2146  */
2147 INT_DEFINE_BEGIN(emulation_assist)
2148         IVEC=0xe40
2149         IHSRR=1
2150         IKVM_REAL=1
2151         IKVM_VIRT=1
2152 INT_DEFINE_END(emulation_assist)
2153 
2154 EXC_REAL_BEGIN(emulation_assist, 0xe40, 0x20)
2155         GEN_INT_ENTRY emulation_assist, virt=0, ool=1
2156 EXC_REAL_END(emulation_assist, 0xe40, 0x20)
2157 EXC_VIRT_BEGIN(emulation_assist, 0x4e40, 0x20)
2158         GEN_INT_ENTRY emulation_assist, virt=1, ool=1
2159 EXC_VIRT_END(emulation_assist, 0x4e40, 0x20)
2160 EXC_COMMON_BEGIN(emulation_assist_common)
2161         GEN_COMMON emulation_assist
2162         addi    r3,r1,STACK_INT_FRAME_REGS
2163         bl      CFUNC(emulation_assist_interrupt)
2164         HANDLER_RESTORE_NVGPRS() /* instruction emulation may change GPRs */
2165         b       interrupt_return_hsrr
2166 
2167 
2168 /**
2169  * Interrupt 0xe60 - Hypervisor Maintenance Interrupt (HMI).
2170  * This is an asynchronous interrupt caused by a Hypervisor Maintenance
2171  * Exception. It is always taken in real mode but uses HSRR registers
2172  * unlike SRESET and MCE.
2173  *
2174  * It is maskable in hardware by clearing MSR[EE], and partially soft-maskable
2175  * with IRQS_DISABLED mask (i.e., local_irq_disable()).
2176  *
2177  * Handling:
2178  * This is a special case, this is handled similarly to machine checks, with an
2179  * initial real mode handler that is not soft-masked, which attempts to fix the
2180  * problem. Then a regular handler which is soft-maskable and reports the
2181  * problem.
2182  *
2183  * The emergency stack is used for the early real mode handler.
2184  *
2185  * XXX: unclear why MCE and HMI schemes could not be made common, e.g.,
2186  * either use soft-masking for the MCE, or use irq_work for the HMI.
2187  *
2188  * KVM:
2189  * Unlike MCE, this calls into KVM without calling the real mode handler
2190  * first.
2191  */
2192 INT_DEFINE_BEGIN(hmi_exception_early)
2193         IVEC=0xe60
2194         IHSRR=1
2195         IREALMODE_COMMON=1
2196         ISTACK=0
2197         IKUAP=0 /* We don't touch AMR here, we never go to virtual mode */
2198         IKVM_REAL=1
2199 INT_DEFINE_END(hmi_exception_early)
2200 
2201 INT_DEFINE_BEGIN(hmi_exception)
2202         IVEC=0xe60
2203         IHSRR=1
2204         IMASK=IRQS_DISABLED
2205         IKVM_REAL=1
2206 INT_DEFINE_END(hmi_exception)
2207 
2208 EXC_REAL_BEGIN(hmi_exception, 0xe60, 0x20)
2209         GEN_INT_ENTRY hmi_exception_early, virt=0, ool=1
2210 EXC_REAL_END(hmi_exception, 0xe60, 0x20)
2211 EXC_VIRT_NONE(0x4e60, 0x20)
2212 
2213 EXC_COMMON_BEGIN(hmi_exception_early_common)
2214         __GEN_REALMODE_COMMON_ENTRY hmi_exception_early
2215 
2216         mr      r10,r1                  /* Save r1 */
2217         ld      r1,PACAEMERGSP(r13)     /* Use emergency stack for realmode */
2218         subi    r1,r1,INT_FRAME_SIZE    /* alloc stack frame            */
2219 
2220         __GEN_COMMON_BODY hmi_exception_early
2221 
2222         addi    r3,r1,STACK_INT_FRAME_REGS
2223         bl      CFUNC(hmi_exception_realmode)
2224         cmpdi   cr0,r3,0
2225         bne     1f
2226 
2227         EXCEPTION_RESTORE_REGS hsrr=1
2228         HRFI_TO_USER_OR_KERNEL
2229 
2230 1:
2231         /*
2232          * Go to virtual mode and pull the HMI event information from
2233          * firmware.
2234          */
2235         EXCEPTION_RESTORE_REGS hsrr=1
2236         GEN_INT_ENTRY hmi_exception, virt=0
2237 
2238 EXC_COMMON_BEGIN(hmi_exception_common)
2239         GEN_COMMON hmi_exception
2240         addi    r3,r1,STACK_INT_FRAME_REGS
2241         bl      CFUNC(handle_hmi_exception)
2242         b       interrupt_return_hsrr
2243 
2244 
2245 /**
2246  * Interrupt 0xe80 - Directed Hypervisor Doorbell Interrupt.
2247  * This is an asynchronous interrupt in response to a msgsnd doorbell.
2248  * Similar to the 0xa00 doorbell but for host rather than guest.
2249  *
2250  * CFAR is not required (similar to doorbell_interrupt), unless KVM HV
2251  * is enabled, in which case it may be a guest exit. Most PowerNV kernels
2252  * include KVM support so it would be nice if this could be dynamically
2253  * patched out if KVM was not currently running any guests.
2254  */
2255 INT_DEFINE_BEGIN(h_doorbell)
2256         IVEC=0xe80
2257         IHSRR=1
2258         IMASK=IRQS_DISABLED
2259         IKVM_REAL=1
2260         IKVM_VIRT=1
2261 #ifndef CONFIG_KVM_BOOK3S_HV_POSSIBLE
2262         ICFAR=0
2263 #endif
2264 INT_DEFINE_END(h_doorbell)
2265 
2266 EXC_REAL_BEGIN(h_doorbell, 0xe80, 0x20)
2267         GEN_INT_ENTRY h_doorbell, virt=0, ool=1
2268 EXC_REAL_END(h_doorbell, 0xe80, 0x20)
2269 EXC_VIRT_BEGIN(h_doorbell, 0x4e80, 0x20)
2270         GEN_INT_ENTRY h_doorbell, virt=1, ool=1
2271 EXC_VIRT_END(h_doorbell, 0x4e80, 0x20)
2272 EXC_COMMON_BEGIN(h_doorbell_common)
2273         GEN_COMMON h_doorbell
2274         addi    r3,r1,STACK_INT_FRAME_REGS
2275 #ifdef CONFIG_PPC_DOORBELL
2276         bl      CFUNC(doorbell_exception)
2277 #else
2278         bl      CFUNC(unknown_async_exception)
2279 #endif
2280         b       interrupt_return_hsrr
2281 
2282 
2283 /**
2284  * Interrupt 0xea0 - Hypervisor Virtualization Interrupt.
2285  * This is an asynchronous interrupt in response to an "external exception".
2286  * Similar to 0x500 but for host only.
2287  *
2288  * Like h_doorbell, CFAR is only required for KVM HV because this can be
2289  * a guest exit.
2290  */
2291 INT_DEFINE_BEGIN(h_virt_irq)
2292         IVEC=0xea0
2293         IHSRR=1
2294         IMASK=IRQS_DISABLED
2295         IKVM_REAL=1
2296         IKVM_VIRT=1
2297 #ifndef CONFIG_KVM_BOOK3S_HV_POSSIBLE
2298         ICFAR=0
2299 #endif
2300 INT_DEFINE_END(h_virt_irq)
2301 
2302 EXC_REAL_BEGIN(h_virt_irq, 0xea0, 0x20)
2303         GEN_INT_ENTRY h_virt_irq, virt=0, ool=1
2304 EXC_REAL_END(h_virt_irq, 0xea0, 0x20)
2305 EXC_VIRT_BEGIN(h_virt_irq, 0x4ea0, 0x20)
2306         GEN_INT_ENTRY h_virt_irq, virt=1, ool=1
2307 EXC_VIRT_END(h_virt_irq, 0x4ea0, 0x20)
2308 EXC_COMMON_BEGIN(h_virt_irq_common)
2309         GEN_COMMON h_virt_irq
2310         addi    r3,r1,STACK_INT_FRAME_REGS
2311         bl      CFUNC(do_IRQ)
2312         b       interrupt_return_hsrr
2313 
2314 
2315 EXC_REAL_NONE(0xec0, 0x20)
2316 EXC_VIRT_NONE(0x4ec0, 0x20)
2317 EXC_REAL_NONE(0xee0, 0x20)
2318 EXC_VIRT_NONE(0x4ee0, 0x20)
2319 
2320 
2321 /*
2322  * Interrupt 0xf00 - Performance Monitor Interrupt (PMI, PMU).
2323  * This is an asynchronous interrupt in response to a PMU exception.
2324  * It is maskable in hardware by clearing MSR[EE], and soft-maskable with
2325  * IRQS_PMI_DISABLED mask (NOTE: NOT local_irq_disable()).
2326  *
2327  * Handling:
2328  * This calls into the perf subsystem.
2329  *
2330  * Like the watchdog soft-nmi, it appears an NMI interrupt to Linux, in that it
2331  * runs under local_irq_disable. However it may be soft-masked in
2332  * powerpc-specific code.
2333  *
2334  * If soft masked, the masked handler will note the pending interrupt for
2335  * replay, and clear MSR[EE] in the interrupted context.
2336  *
2337  * CFAR is not used by perf interrupts so not required.
2338  */
2339 INT_DEFINE_BEGIN(performance_monitor)
2340         IVEC=0xf00
2341         IMASK=IRQS_PMI_DISABLED
2342 #ifdef CONFIG_KVM_BOOK3S_PR_POSSIBLE
2343         IKVM_REAL=1
2344 #endif
2345         ICFAR=0
2346 INT_DEFINE_END(performance_monitor)
2347 
2348 EXC_REAL_BEGIN(performance_monitor, 0xf00, 0x20)
2349         GEN_INT_ENTRY performance_monitor, virt=0, ool=1
2350 EXC_REAL_END(performance_monitor, 0xf00, 0x20)
2351 EXC_VIRT_BEGIN(performance_monitor, 0x4f00, 0x20)
2352         GEN_INT_ENTRY performance_monitor, virt=1, ool=1
2353 EXC_VIRT_END(performance_monitor, 0x4f00, 0x20)
2354 EXC_COMMON_BEGIN(performance_monitor_common)
2355         GEN_COMMON performance_monitor
2356         addi    r3,r1,STACK_INT_FRAME_REGS
2357         lbz     r4,PACAIRQSOFTMASK(r13)
2358         cmpdi   r4,IRQS_ENABLED
2359         bne     1f
2360         bl      CFUNC(performance_monitor_exception_async)
2361         b       interrupt_return_srr
2362 1:
2363         bl      CFUNC(performance_monitor_exception_nmi)
2364         /* Clear MSR_RI before setting SRR0 and SRR1. */
2365         li      r9,0
2366         mtmsrd  r9,1
2367 
2368         kuap_kernel_restore r9, r10
2369 
2370         EXCEPTION_RESTORE_REGS hsrr=0
2371         RFI_TO_KERNEL
2372 
2373 /**
2374  * Interrupt 0xf20 - Vector Unavailable Interrupt.
2375  * This is a synchronous interrupt in response to
2376  * executing a vector (or altivec) instruction with MSR[VEC]=0.
2377  * Similar to FP unavailable.
2378  */
2379 INT_DEFINE_BEGIN(altivec_unavailable)
2380         IVEC=0xf20
2381 #ifdef CONFIG_KVM_BOOK3S_PR_POSSIBLE
2382         IKVM_REAL=1
2383 #endif
2384         IMSR_R12=1
2385 INT_DEFINE_END(altivec_unavailable)
2386 
2387 EXC_REAL_BEGIN(altivec_unavailable, 0xf20, 0x20)
2388         GEN_INT_ENTRY altivec_unavailable, virt=0, ool=1
2389 EXC_REAL_END(altivec_unavailable, 0xf20, 0x20)
2390 EXC_VIRT_BEGIN(altivec_unavailable, 0x4f20, 0x20)
2391         GEN_INT_ENTRY altivec_unavailable, virt=1, ool=1
2392 EXC_VIRT_END(altivec_unavailable, 0x4f20, 0x20)
2393 EXC_COMMON_BEGIN(altivec_unavailable_common)
2394         GEN_COMMON altivec_unavailable
2395 #ifdef CONFIG_ALTIVEC
2396 BEGIN_FTR_SECTION
2397         beq     1f
2398 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
2399   BEGIN_FTR_SECTION_NESTED(69)
2400         /* Test if 2 TM state bits are zero.  If non-zero (ie. userspace was in
2401          * transaction), go do TM stuff
2402          */
2403         rldicl. r0, r12, (64-MSR_TS_LG), (64-2)
2404         bne-    2f
2405   END_FTR_SECTION_NESTED(CPU_FTR_TM, CPU_FTR_TM, 69)
2406 #endif
2407         bl      CFUNC(load_up_altivec)
2408         b       fast_interrupt_return_srr
2409 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
2410 2:      /* User process was in a transaction */
2411         addi    r3,r1,STACK_INT_FRAME_REGS
2412         bl      CFUNC(altivec_unavailable_tm)
2413         b       interrupt_return_srr
2414 #endif
2415 1:
2416 END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC)
2417 #endif
2418         addi    r3,r1,STACK_INT_FRAME_REGS
2419         bl      CFUNC(altivec_unavailable_exception)
2420         b       interrupt_return_srr
2421 
2422 
2423 /**
2424  * Interrupt 0xf40 - VSX Unavailable Interrupt.
2425  * This is a synchronous interrupt in response to
2426  * executing a VSX instruction with MSR[VSX]=0.
2427  * Similar to FP unavailable.
2428  */
2429 INT_DEFINE_BEGIN(vsx_unavailable)
2430         IVEC=0xf40
2431 #ifdef CONFIG_KVM_BOOK3S_PR_POSSIBLE
2432         IKVM_REAL=1
2433 #endif
2434         IMSR_R12=1
2435 INT_DEFINE_END(vsx_unavailable)
2436 
2437 EXC_REAL_BEGIN(vsx_unavailable, 0xf40, 0x20)
2438         GEN_INT_ENTRY vsx_unavailable, virt=0, ool=1
2439 EXC_REAL_END(vsx_unavailable, 0xf40, 0x20)
2440 EXC_VIRT_BEGIN(vsx_unavailable, 0x4f40, 0x20)
2441         GEN_INT_ENTRY vsx_unavailable, virt=1, ool=1
2442 EXC_VIRT_END(vsx_unavailable, 0x4f40, 0x20)
2443 EXC_COMMON_BEGIN(vsx_unavailable_common)
2444         GEN_COMMON vsx_unavailable
2445 #ifdef CONFIG_VSX
2446 BEGIN_FTR_SECTION
2447         beq     1f
2448 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
2449   BEGIN_FTR_SECTION_NESTED(69)
2450         /* Test if 2 TM state bits are zero.  If non-zero (ie. userspace was in
2451          * transaction), go do TM stuff
2452          */
2453         rldicl. r0, r12, (64-MSR_TS_LG), (64-2)
2454         bne-    2f
2455   END_FTR_SECTION_NESTED(CPU_FTR_TM, CPU_FTR_TM, 69)
2456 #endif
2457         b       load_up_vsx
2458 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
2459 2:      /* User process was in a transaction */
2460         addi    r3,r1,STACK_INT_FRAME_REGS
2461         bl      CFUNC(vsx_unavailable_tm)
2462         b       interrupt_return_srr
2463 #endif
2464 1:
2465 END_FTR_SECTION_IFSET(CPU_FTR_VSX)
2466 #endif
2467         addi    r3,r1,STACK_INT_FRAME_REGS
2468         bl      CFUNC(vsx_unavailable_exception)
2469         b       interrupt_return_srr
2470 
2471 
2472 /**
2473  * Interrupt 0xf60 - Facility Unavailable Interrupt.
2474  * This is a synchronous interrupt in response to
2475  * executing an instruction without access to the facility that can be
2476  * resolved by the OS (e.g., FSCR, MSR).
2477  * Similar to FP unavailable.
2478  */
2479 INT_DEFINE_BEGIN(facility_unavailable)
2480         IVEC=0xf60
2481 #ifdef CONFIG_KVM_BOOK3S_PR_POSSIBLE
2482         IKVM_REAL=1
2483 #endif
2484 INT_DEFINE_END(facility_unavailable)
2485 
2486 EXC_REAL_BEGIN(facility_unavailable, 0xf60, 0x20)
2487         GEN_INT_ENTRY facility_unavailable, virt=0, ool=1
2488 EXC_REAL_END(facility_unavailable, 0xf60, 0x20)
2489 EXC_VIRT_BEGIN(facility_unavailable, 0x4f60, 0x20)
2490         GEN_INT_ENTRY facility_unavailable, virt=1, ool=1
2491 EXC_VIRT_END(facility_unavailable, 0x4f60, 0x20)
2492 EXC_COMMON_BEGIN(facility_unavailable_common)
2493         GEN_COMMON facility_unavailable
2494         addi    r3,r1,STACK_INT_FRAME_REGS
2495         bl      CFUNC(facility_unavailable_exception)
2496         HANDLER_RESTORE_NVGPRS() /* instruction emulation may change GPRs */
2497         b       interrupt_return_srr
2498 
2499 
2500 /**
2501  * Interrupt 0xf60 - Hypervisor Facility Unavailable Interrupt.
2502  * This is a synchronous interrupt in response to
2503  * executing an instruction without access to the facility that can only
2504  * be resolved in HV mode (e.g., HFSCR).
2505  * Similar to FP unavailable.
2506  */
2507 INT_DEFINE_BEGIN(h_facility_unavailable)
2508         IVEC=0xf80
2509         IHSRR=1
2510         IKVM_REAL=1
2511         IKVM_VIRT=1
2512 INT_DEFINE_END(h_facility_unavailable)
2513 
2514 EXC_REAL_BEGIN(h_facility_unavailable, 0xf80, 0x20)
2515         GEN_INT_ENTRY h_facility_unavailable, virt=0, ool=1
2516 EXC_REAL_END(h_facility_unavailable, 0xf80, 0x20)
2517 EXC_VIRT_BEGIN(h_facility_unavailable, 0x4f80, 0x20)
2518         GEN_INT_ENTRY h_facility_unavailable, virt=1, ool=1
2519 EXC_VIRT_END(h_facility_unavailable, 0x4f80, 0x20)
2520 EXC_COMMON_BEGIN(h_facility_unavailable_common)
2521         GEN_COMMON h_facility_unavailable
2522         addi    r3,r1,STACK_INT_FRAME_REGS
2523         bl      CFUNC(facility_unavailable_exception)
2524         /* XXX Shouldn't be necessary in practice */
2525         HANDLER_RESTORE_NVGPRS()
2526         b       interrupt_return_hsrr
2527 
2528 
2529 EXC_REAL_NONE(0xfa0, 0x20)
2530 EXC_VIRT_NONE(0x4fa0, 0x20)
2531 EXC_REAL_NONE(0xfc0, 0x20)
2532 EXC_VIRT_NONE(0x4fc0, 0x20)
2533 EXC_REAL_NONE(0xfe0, 0x20)
2534 EXC_VIRT_NONE(0x4fe0, 0x20)
2535 
2536 EXC_REAL_NONE(0x1000, 0x100)
2537 EXC_VIRT_NONE(0x5000, 0x100)
2538 EXC_REAL_NONE(0x1100, 0x100)
2539 EXC_VIRT_NONE(0x5100, 0x100)
2540 
2541 #ifdef CONFIG_CBE_RAS
2542 INT_DEFINE_BEGIN(cbe_system_error)
2543         IVEC=0x1200
2544         IHSRR=1
2545 INT_DEFINE_END(cbe_system_error)
2546 
2547 EXC_REAL_BEGIN(cbe_system_error, 0x1200, 0x100)
2548         GEN_INT_ENTRY cbe_system_error, virt=0
2549 EXC_REAL_END(cbe_system_error, 0x1200, 0x100)
2550 EXC_VIRT_NONE(0x5200, 0x100)
2551 EXC_COMMON_BEGIN(cbe_system_error_common)
2552         GEN_COMMON cbe_system_error
2553         addi    r3,r1,STACK_INT_FRAME_REGS
2554         bl      CFUNC(cbe_system_error_exception)
2555         b       interrupt_return_hsrr
2556 
2557 #else /* CONFIG_CBE_RAS */
2558 EXC_REAL_NONE(0x1200, 0x100)
2559 EXC_VIRT_NONE(0x5200, 0x100)
2560 #endif
2561 
2562 /**
2563  * Interrupt 0x1300 - Instruction Address Breakpoint Interrupt.
2564  * This has been removed from the ISA before 2.01, which is the earliest
2565  * 64-bit BookS ISA supported, however the G5 / 970 implements this
2566  * interrupt with a non-architected feature available through the support
2567  * processor interface.
2568  */
2569 INT_DEFINE_BEGIN(instruction_breakpoint)
2570         IVEC=0x1300
2571 #ifdef CONFIG_KVM_BOOK3S_PR_POSSIBLE
2572         IKVM_REAL=1
2573 #endif
2574 INT_DEFINE_END(instruction_breakpoint)
2575 
2576 EXC_REAL_BEGIN(instruction_breakpoint, 0x1300, 0x100)
2577         GEN_INT_ENTRY instruction_breakpoint, virt=0
2578 EXC_REAL_END(instruction_breakpoint, 0x1300, 0x100)
2579 EXC_VIRT_BEGIN(instruction_breakpoint, 0x5300, 0x100)
2580         GEN_INT_ENTRY instruction_breakpoint, virt=1
2581 EXC_VIRT_END(instruction_breakpoint, 0x5300, 0x100)
2582 EXC_COMMON_BEGIN(instruction_breakpoint_common)
2583         GEN_COMMON instruction_breakpoint
2584         addi    r3,r1,STACK_INT_FRAME_REGS
2585         bl      CFUNC(instruction_breakpoint_exception)
2586         b       interrupt_return_srr
2587 
2588 
2589 EXC_REAL_NONE(0x1400, 0x100)
2590 EXC_VIRT_NONE(0x5400, 0x100)
2591 
2592 /**
2593  * Interrupt 0x1500 - Soft Patch Interrupt
2594  *
2595  * Handling:
2596  * This is an implementation specific interrupt which can be used for a
2597  * range of exceptions.
2598  *
2599  * This interrupt handler is unique in that it runs the denormal assist
2600  * code even for guests (and even in guest context) without going to KVM,
2601  * for speed. POWER9 does not raise denorm exceptions, so this special case
2602  * could be phased out in future to reduce special cases.
2603  */
2604 INT_DEFINE_BEGIN(denorm_exception)
2605         IVEC=0x1500
2606         IHSRR=1
2607         IBRANCH_TO_COMMON=0
2608         IKVM_REAL=1
2609 INT_DEFINE_END(denorm_exception)
2610 
2611 EXC_REAL_BEGIN(denorm_exception, 0x1500, 0x100)
2612         GEN_INT_ENTRY denorm_exception, virt=0
2613 #ifdef CONFIG_PPC_DENORMALISATION
2614         andis.  r10,r12,(HSRR1_DENORM)@h /* denorm? */
2615         bne+    denorm_assist
2616 #endif
2617         GEN_BRANCH_TO_COMMON denorm_exception, virt=0
2618 EXC_REAL_END(denorm_exception, 0x1500, 0x100)
2619 #ifdef CONFIG_PPC_DENORMALISATION
2620 EXC_VIRT_BEGIN(denorm_exception, 0x5500, 0x100)
2621         GEN_INT_ENTRY denorm_exception, virt=1
2622         andis.  r10,r12,(HSRR1_DENORM)@h /* denorm? */
2623         bne+    denorm_assist
2624         GEN_BRANCH_TO_COMMON denorm_exception, virt=1
2625 EXC_VIRT_END(denorm_exception, 0x5500, 0x100)
2626 #else
2627 EXC_VIRT_NONE(0x5500, 0x100)
2628 #endif
2629 
2630 #ifdef CONFIG_PPC_DENORMALISATION
2631 TRAMP_REAL_BEGIN(denorm_assist)
2632 BEGIN_FTR_SECTION
2633 /*
2634  * To denormalise we need to move a copy of the register to itself.
2635  * For POWER6 do that here for all FP regs.
2636  */
2637         mfmsr   r10
2638         ori     r10,r10,(MSR_FP|MSR_FE0|MSR_FE1)
2639         xori    r10,r10,(MSR_FE0|MSR_FE1)
2640         mtmsrd  r10
2641         sync
2642 
2643         .Lreg=0
2644         .rept 32
2645         fmr     .Lreg,.Lreg
2646         .Lreg=.Lreg+1
2647         .endr
2648 
2649 FTR_SECTION_ELSE
2650 /*
2651  * To denormalise we need to move a copy of the register to itself.
2652  * For POWER7 do that here for the first 32 VSX registers only.
2653  */
2654         mfmsr   r10
2655         oris    r10,r10,MSR_VSX@h
2656         mtmsrd  r10
2657         sync
2658 
2659         .Lreg=0
2660         .rept 32
2661         XVCPSGNDP(.Lreg,.Lreg,.Lreg)
2662         .Lreg=.Lreg+1
2663         .endr
2664 
2665 ALT_FTR_SECTION_END_IFCLR(CPU_FTR_ARCH_206)
2666 
2667 BEGIN_FTR_SECTION
2668         b       denorm_done
2669 END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_207S)
2670 /*
2671  * To denormalise we need to move a copy of the register to itself.
2672  * For POWER8 we need to do that for all 64 VSX registers
2673  */
2674         .Lreg=32
2675         .rept 32
2676         XVCPSGNDP(.Lreg,.Lreg,.Lreg)
2677         .Lreg=.Lreg+1
2678         .endr
2679 
2680 denorm_done:
2681         mfspr   r11,SPRN_HSRR0
2682         subi    r11,r11,4
2683         mtspr   SPRN_HSRR0,r11
2684         mtcrf   0x80,r9
2685         ld      r9,PACA_EXGEN+EX_R9(r13)
2686 BEGIN_FTR_SECTION
2687         ld      r10,PACA_EXGEN+EX_PPR(r13)
2688         mtspr   SPRN_PPR,r10
2689 END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
2690 BEGIN_FTR_SECTION
2691         ld      r10,PACA_EXGEN+EX_CFAR(r13)
2692         mtspr   SPRN_CFAR,r10
2693 END_FTR_SECTION_IFSET(CPU_FTR_CFAR)
2694         li      r10,0
2695         stb     r10,PACAHSRR_VALID(r13)
2696         ld      r10,PACA_EXGEN+EX_R10(r13)
2697         ld      r11,PACA_EXGEN+EX_R11(r13)
2698         ld      r12,PACA_EXGEN+EX_R12(r13)
2699         ld      r13,PACA_EXGEN+EX_R13(r13)
2700         HRFI_TO_UNKNOWN
2701         b       .
2702 #endif
2703 
2704 EXC_COMMON_BEGIN(denorm_exception_common)
2705         GEN_COMMON denorm_exception
2706         addi    r3,r1,STACK_INT_FRAME_REGS
2707         bl      CFUNC(unknown_exception)
2708         b       interrupt_return_hsrr
2709 
2710 
2711 #ifdef CONFIG_CBE_RAS
2712 INT_DEFINE_BEGIN(cbe_maintenance)
2713         IVEC=0x1600
2714         IHSRR=1
2715 INT_DEFINE_END(cbe_maintenance)
2716 
2717 EXC_REAL_BEGIN(cbe_maintenance, 0x1600, 0x100)
2718         GEN_INT_ENTRY cbe_maintenance, virt=0
2719 EXC_REAL_END(cbe_maintenance, 0x1600, 0x100)
2720 EXC_VIRT_NONE(0x5600, 0x100)
2721 EXC_COMMON_BEGIN(cbe_maintenance_common)
2722         GEN_COMMON cbe_maintenance
2723         addi    r3,r1,STACK_INT_FRAME_REGS
2724         bl      CFUNC(cbe_maintenance_exception)
2725         b       interrupt_return_hsrr
2726 
2727 #else /* CONFIG_CBE_RAS */
2728 EXC_REAL_NONE(0x1600, 0x100)
2729 EXC_VIRT_NONE(0x5600, 0x100)
2730 #endif
2731 
2732 
2733 INT_DEFINE_BEGIN(altivec_assist)
2734         IVEC=0x1700
2735 #ifdef CONFIG_KVM_BOOK3S_PR_POSSIBLE
2736         IKVM_REAL=1
2737 #endif
2738 INT_DEFINE_END(altivec_assist)
2739 
2740 EXC_REAL_BEGIN(altivec_assist, 0x1700, 0x100)
2741         GEN_INT_ENTRY altivec_assist, virt=0
2742 EXC_REAL_END(altivec_assist, 0x1700, 0x100)
2743 EXC_VIRT_BEGIN(altivec_assist, 0x5700, 0x100)
2744         GEN_INT_ENTRY altivec_assist, virt=1
2745 EXC_VIRT_END(altivec_assist, 0x5700, 0x100)
2746 EXC_COMMON_BEGIN(altivec_assist_common)
2747         GEN_COMMON altivec_assist
2748         addi    r3,r1,STACK_INT_FRAME_REGS
2749 #ifdef CONFIG_ALTIVEC
2750         bl      CFUNC(altivec_assist_exception)
2751         HANDLER_RESTORE_NVGPRS() /* instruction emulation may change GPRs */
2752 #else
2753         bl      CFUNC(unknown_exception)
2754 #endif
2755         b       interrupt_return_srr
2756 
2757 
2758 #ifdef CONFIG_CBE_RAS
2759 INT_DEFINE_BEGIN(cbe_thermal)
2760         IVEC=0x1800
2761         IHSRR=1
2762 INT_DEFINE_END(cbe_thermal)
2763 
2764 EXC_REAL_BEGIN(cbe_thermal, 0x1800, 0x100)
2765         GEN_INT_ENTRY cbe_thermal, virt=0
2766 EXC_REAL_END(cbe_thermal, 0x1800, 0x100)
2767 EXC_VIRT_NONE(0x5800, 0x100)
2768 EXC_COMMON_BEGIN(cbe_thermal_common)
2769         GEN_COMMON cbe_thermal
2770         addi    r3,r1,STACK_INT_FRAME_REGS
2771         bl      CFUNC(cbe_thermal_exception)
2772         b       interrupt_return_hsrr
2773 
2774 #else /* CONFIG_CBE_RAS */
2775 EXC_REAL_NONE(0x1800, 0x100)
2776 EXC_VIRT_NONE(0x5800, 0x100)
2777 #endif
2778 
2779 
2780 #ifdef CONFIG_PPC_WATCHDOG
2781 
2782 INT_DEFINE_BEGIN(soft_nmi)
2783         IVEC=0x900
2784         ISTACK=0
2785         ICFAR=0
2786 INT_DEFINE_END(soft_nmi)
2787 
2788 /*
2789  * Branch to soft_nmi_interrupt using the emergency stack. The emergency
2790  * stack is one that is usable by maskable interrupts so long as MSR_EE
2791  * remains off. It is used for recovery when something has corrupted the
2792  * normal kernel stack, for example. The "soft NMI" must not use the process
2793  * stack because we want irq disabled sections to avoid touching the stack
2794  * at all (other than PMU interrupts), so use the emergency stack for this,
2795  * and run it entirely with interrupts hard disabled.
2796  */
2797 EXC_COMMON_BEGIN(soft_nmi_common)
2798         mr      r10,r1
2799         ld      r1,PACAEMERGSP(r13)
2800         subi    r1,r1,INT_FRAME_SIZE
2801         __GEN_COMMON_BODY soft_nmi
2802 
2803         addi    r3,r1,STACK_INT_FRAME_REGS
2804         bl      CFUNC(soft_nmi_interrupt)
2805 
2806         /* Clear MSR_RI before setting SRR0 and SRR1. */
2807         li      r9,0
2808         mtmsrd  r9,1
2809 
2810         kuap_kernel_restore r9, r10
2811 
2812         EXCEPTION_RESTORE_REGS hsrr=0
2813         RFI_TO_KERNEL
2814 
2815 #endif /* CONFIG_PPC_WATCHDOG */
2816 
2817 /*
2818  * An interrupt came in while soft-disabled. We set paca->irq_happened, then:
2819  * - If it was a decrementer interrupt, we bump the dec to max and return.
2820  * - If it was a doorbell we return immediately since doorbells are edge
2821  *   triggered and won't automatically refire.
2822  * - If it was a HMI we return immediately since we handled it in realmode
2823  *   and it won't refire.
2824  * - Else it is one of PACA_IRQ_MUST_HARD_MASK, so hard disable and return.
2825  * This is called with r10 containing the value to OR to the paca field.
2826  */
2827 .macro MASKED_INTERRUPT hsrr=0
2828         .if \hsrr
2829 masked_Hinterrupt:
2830         .else
2831 masked_interrupt:
2832         .endif
2833         stw     r9,PACA_EXGEN+EX_CCR(r13)
2834 #ifdef CONFIG_PPC_IRQ_SOFT_MASK_DEBUG
2835         /*
2836          * Ensure there was no previous MUST_HARD_MASK interrupt or
2837          * HARD_DIS setting. If this does fire, the interrupt is still
2838          * masked and MSR[EE] will be cleared on return, so no need to
2839          * panic, but somebody probably enabled MSR[EE] under
2840          * PACA_IRQ_HARD_DIS, mtmsr(mfmsr() | MSR_x) being a common
2841          * cause.
2842          */
2843         lbz     r9,PACAIRQHAPPENED(r13)
2844         andi.   r9,r9,(PACA_IRQ_MUST_HARD_MASK|PACA_IRQ_HARD_DIS)
2845 0:      tdnei   r9,0
2846         EMIT_WARN_ENTRY 0b,__FILE__,__LINE__,(BUGFLAG_WARNING | BUGFLAG_ONCE)
2847 #endif
2848         lbz     r9,PACAIRQHAPPENED(r13)
2849         or      r9,r9,r10
2850         stb     r9,PACAIRQHAPPENED(r13)
2851 
2852         .if ! \hsrr
2853         cmpwi   r10,PACA_IRQ_DEC
2854         bne     1f
2855         LOAD_REG_IMMEDIATE(r9, 0x7fffffff)
2856         mtspr   SPRN_DEC,r9
2857 #ifdef CONFIG_PPC_WATCHDOG
2858         lwz     r9,PACA_EXGEN+EX_CCR(r13)
2859         b       soft_nmi_common
2860 #else
2861         b       2f
2862 #endif
2863         .endif
2864 
2865 1:      andi.   r10,r10,PACA_IRQ_MUST_HARD_MASK
2866         beq     2f
2867         xori    r12,r12,MSR_EE  /* clear MSR_EE */
2868         .if \hsrr
2869         mtspr   SPRN_HSRR1,r12
2870         .else
2871         mtspr   SPRN_SRR1,r12
2872         .endif
2873         ori     r9,r9,PACA_IRQ_HARD_DIS
2874         stb     r9,PACAIRQHAPPENED(r13)
2875 2:      /* done */
2876         li      r9,0
2877         .if \hsrr
2878         stb     r9,PACAHSRR_VALID(r13)
2879         .else
2880         stb     r9,PACASRR_VALID(r13)
2881         .endif
2882 
2883         SEARCH_RESTART_TABLE
2884         cmpdi   r12,0
2885         beq     3f
2886         .if \hsrr
2887         mtspr   SPRN_HSRR0,r12
2888         .else
2889         mtspr   SPRN_SRR0,r12
2890         .endif
2891 3:
2892 
2893         ld      r9,PACA_EXGEN+EX_CTR(r13)
2894         mtctr   r9
2895         lwz     r9,PACA_EXGEN+EX_CCR(r13)
2896         mtcrf   0x80,r9
2897         std     r1,PACAR1(r13)
2898         ld      r9,PACA_EXGEN+EX_R9(r13)
2899         ld      r10,PACA_EXGEN+EX_R10(r13)
2900         ld      r11,PACA_EXGEN+EX_R11(r13)
2901         ld      r12,PACA_EXGEN+EX_R12(r13)
2902         ld      r13,PACA_EXGEN+EX_R13(r13)
2903         /* May return to masked low address where r13 is not set up */
2904         .if \hsrr
2905         HRFI_TO_KERNEL
2906         .else
2907         RFI_TO_KERNEL
2908         .endif
2909         b       .
2910 .endm
2911 
2912 TRAMP_REAL_BEGIN(stf_barrier_fallback)
2913         std     r9,PACA_EXRFI+EX_R9(r13)
2914         std     r10,PACA_EXRFI+EX_R10(r13)
2915         sync
2916         ld      r9,PACA_EXRFI+EX_R9(r13)
2917         ld      r10,PACA_EXRFI+EX_R10(r13)
2918         ori     31,31,0
2919         .rept 14
2920         b       1f
2921 1:
2922         .endr
2923         blr
2924 
2925 /* Clobbers r10, r11, ctr */
2926 .macro L1D_DISPLACEMENT_FLUSH
2927         ld      r10,PACA_RFI_FLUSH_FALLBACK_AREA(r13)
2928         ld      r11,PACA_L1D_FLUSH_SIZE(r13)
2929         srdi    r11,r11,(7 + 3) /* 128 byte lines, unrolled 8x */
2930         mtctr   r11
2931         DCBT_BOOK3S_STOP_ALL_STREAM_IDS(r11) /* Stop prefetch streams */
2932 
2933         /* order ld/st prior to dcbt stop all streams with flushing */
2934         sync
2935 
2936         /*
2937          * The load addresses are at staggered offsets within cachelines,
2938          * which suits some pipelines better (on others it should not
2939          * hurt).
2940          */
2941 1:
2942         ld      r11,(0x80 + 8)*0(r10)
2943         ld      r11,(0x80 + 8)*1(r10)
2944         ld      r11,(0x80 + 8)*2(r10)
2945         ld      r11,(0x80 + 8)*3(r10)
2946         ld      r11,(0x80 + 8)*4(r10)
2947         ld      r11,(0x80 + 8)*5(r10)
2948         ld      r11,(0x80 + 8)*6(r10)
2949         ld      r11,(0x80 + 8)*7(r10)
2950         addi    r10,r10,0x80*8
2951         bdnz    1b
2952 .endm
2953 
2954 TRAMP_REAL_BEGIN(entry_flush_fallback)
2955         std     r9,PACA_EXRFI+EX_R9(r13)
2956         std     r10,PACA_EXRFI+EX_R10(r13)
2957         std     r11,PACA_EXRFI+EX_R11(r13)
2958         mfctr   r9
2959         L1D_DISPLACEMENT_FLUSH
2960         mtctr   r9
2961         ld      r9,PACA_EXRFI+EX_R9(r13)
2962         ld      r10,PACA_EXRFI+EX_R10(r13)
2963         ld      r11,PACA_EXRFI+EX_R11(r13)
2964         blr
2965 
2966 /*
2967  * The SCV entry flush happens with interrupts enabled, so it must disable
2968  * to prevent EXRFI being clobbered by NMIs (e.g., soft_nmi_common). r10
2969  * (containing LR) does not need to be preserved here because scv entry
2970  * puts 0 in the pt_regs, CTR can be clobbered for the same reason.
2971  */
2972 TRAMP_REAL_BEGIN(scv_entry_flush_fallback)
2973         li      r10,0
2974         mtmsrd  r10,1
2975         lbz     r10,PACAIRQHAPPENED(r13)
2976         ori     r10,r10,PACA_IRQ_HARD_DIS
2977         stb     r10,PACAIRQHAPPENED(r13)
2978         std     r11,PACA_EXRFI+EX_R11(r13)
2979         L1D_DISPLACEMENT_FLUSH
2980         ld      r11,PACA_EXRFI+EX_R11(r13)
2981         li      r10,MSR_RI
2982         mtmsrd  r10,1
2983         blr
2984 
2985 TRAMP_REAL_BEGIN(rfi_flush_fallback)
2986         SET_SCRATCH0(r13);
2987         GET_PACA(r13);
2988         std     r1,PACA_EXRFI+EX_R12(r13)
2989         ld      r1,PACAKSAVE(r13)
2990         std     r9,PACA_EXRFI+EX_R9(r13)
2991         std     r10,PACA_EXRFI+EX_R10(r13)
2992         std     r11,PACA_EXRFI+EX_R11(r13)
2993         mfctr   r9
2994         L1D_DISPLACEMENT_FLUSH
2995         mtctr   r9
2996         ld      r9,PACA_EXRFI+EX_R9(r13)
2997         ld      r10,PACA_EXRFI+EX_R10(r13)
2998         ld      r11,PACA_EXRFI+EX_R11(r13)
2999         ld      r1,PACA_EXRFI+EX_R12(r13)
3000         GET_SCRATCH0(r13);
3001         rfid
3002 
3003 TRAMP_REAL_BEGIN(hrfi_flush_fallback)
3004         SET_SCRATCH0(r13);
3005         GET_PACA(r13);
3006         std     r1,PACA_EXRFI+EX_R12(r13)
3007         ld      r1,PACAKSAVE(r13)
3008         std     r9,PACA_EXRFI+EX_R9(r13)
3009         std     r10,PACA_EXRFI+EX_R10(r13)
3010         std     r11,PACA_EXRFI+EX_R11(r13)
3011         mfctr   r9
3012         L1D_DISPLACEMENT_FLUSH
3013         mtctr   r9
3014         ld      r9,PACA_EXRFI+EX_R9(r13)
3015         ld      r10,PACA_EXRFI+EX_R10(r13)
3016         ld      r11,PACA_EXRFI+EX_R11(r13)
3017         ld      r1,PACA_EXRFI+EX_R12(r13)
3018         GET_SCRATCH0(r13);
3019         hrfid
3020 
3021 TRAMP_REAL_BEGIN(rfscv_flush_fallback)
3022         /* system call volatile */
3023         mr      r7,r13
3024         GET_PACA(r13);
3025         mr      r8,r1
3026         ld      r1,PACAKSAVE(r13)
3027         mfctr   r9
3028         ld      r10,PACA_RFI_FLUSH_FALLBACK_AREA(r13)
3029         ld      r11,PACA_L1D_FLUSH_SIZE(r13)
3030         srdi    r11,r11,(7 + 3) /* 128 byte lines, unrolled 8x */
3031         mtctr   r11
3032         DCBT_BOOK3S_STOP_ALL_STREAM_IDS(r11) /* Stop prefetch streams */
3033 
3034         /* order ld/st prior to dcbt stop all streams with flushing */
3035         sync
3036 
3037         /*
3038          * The load adresses are at staggered offsets within cachelines,
3039          * which suits some pipelines better (on others it should not
3040          * hurt).
3041          */
3042 1:
3043         ld      r11,(0x80 + 8)*0(r10)
3044         ld      r11,(0x80 + 8)*1(r10)
3045         ld      r11,(0x80 + 8)*2(r10)
3046         ld      r11,(0x80 + 8)*3(r10)
3047         ld      r11,(0x80 + 8)*4(r10)
3048         ld      r11,(0x80 + 8)*5(r10)
3049         ld      r11,(0x80 + 8)*6(r10)
3050         ld      r11,(0x80 + 8)*7(r10)
3051         addi    r10,r10,0x80*8
3052         bdnz    1b
3053 
3054         mtctr   r9
3055         li      r9,0
3056         li      r10,0
3057         li      r11,0
3058         mr      r1,r8
3059         mr      r13,r7
3060         RFSCV
3061 
3062 USE_TEXT_SECTION()
3063 
3064 #ifdef CONFIG_KVM_BOOK3S_64_HANDLER
3065 kvm_interrupt:
3066         /*
3067          * The conditional branch in KVMTEST can't reach all the way,
3068          * make a stub.
3069          */
3070         b       kvmppc_interrupt
3071 #endif
3072 
3073 _GLOBAL(do_uaccess_flush)
3074         UACCESS_FLUSH_FIXUP_SECTION
3075         nop
3076         nop
3077         nop
3078         blr
3079         L1D_DISPLACEMENT_FLUSH
3080         blr
3081 _ASM_NOKPROBE_SYMBOL(do_uaccess_flush)
3082 EXPORT_SYMBOL(do_uaccess_flush)
3083 
3084 
3085 MASKED_INTERRUPT
3086 MASKED_INTERRUPT hsrr=1
3087 
3088 USE_FIXED_SECTION(virt_trampolines)
3089         /*
3090          * All code below __end_soft_masked is treated as soft-masked. If
3091          * any code runs here with MSR[EE]=1, it must then cope with pending
3092          * soft interrupt being raised (i.e., by ensuring it is replayed).
3093          *
3094          * The __end_interrupts marker must be past the out-of-line (OOL)
3095          * handlers, so that they are copied to real address 0x100 when running
3096          * a relocatable kernel. This ensures they can be reached from the short
3097          * trampoline handlers (like 0x4f00, 0x4f20, etc.) which branch
3098          * directly, without using LOAD_HANDLER().
3099          */
3100         .align  7
3101         .globl  __end_interrupts
3102 __end_interrupts:
3103 DEFINE_FIXED_SYMBOL(__end_interrupts, virt_trampolines)
3104 
3105 CLOSE_FIXED_SECTION(real_vectors);
3106 CLOSE_FIXED_SECTION(real_trampolines);
3107 CLOSE_FIXED_SECTION(virt_vectors);
3108 CLOSE_FIXED_SECTION(virt_trampolines);
3109 
3110 USE_TEXT_SECTION()
3111 
3112 /* MSR[RI] should be clear because this uses SRR[01] */
3113 _GLOBAL(enable_machine_check)
3114         mflr    r0
3115         bcl     20,31,$+4
3116 0:      mflr    r3
3117         addi    r3,r3,(1f - 0b)
3118         mtspr   SPRN_SRR0,r3
3119         mfmsr   r3
3120         ori     r3,r3,MSR_ME
3121         mtspr   SPRN_SRR1,r3
3122         RFI_TO_KERNEL
3123 1:      mtlr    r0
3124         blr
3125 
3126 /* MSR[RI] should be clear because this uses SRR[01] */
3127 SYM_FUNC_START_LOCAL(disable_machine_check)
3128         mflr    r0
3129         bcl     20,31,$+4
3130 0:      mflr    r3
3131         addi    r3,r3,(1f - 0b)
3132         mtspr   SPRN_SRR0,r3
3133         mfmsr   r3
3134         li      r4,MSR_ME
3135         andc    r3,r3,r4
3136         mtspr   SPRN_SRR1,r3
3137         RFI_TO_KERNEL
3138 1:      mtlr    r0
3139         blr
3140 SYM_FUNC_END(disable_machine_check)

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