1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3 * Copyright (C) 2012 ARM Ltd.
4 */
5 #ifndef __ASM_FP_H
6 #define __ASM_FP_H
7
8 #include <asm/errno.h>
9 #include <asm/ptrace.h>
10 #include <asm/processor.h>
11 #include <asm/sigcontext.h>
12 #include <asm/sysreg.h>
13
14 #ifndef __ASSEMBLY__
15
16 #include <linux/bitmap.h>
17 #include <linux/build_bug.h>
18 #include <linux/bug.h>
19 #include <linux/cache.h>
20 #include <linux/init.h>
21 #include <linux/stddef.h>
22 #include <linux/types.h>
23
24 /* Masks for extracting the FPSR and FPCR from the FPSCR */
25 #define VFP_FPSCR_STAT_MASK 0xf800009f
26 #define VFP_FPSCR_CTRL_MASK 0x07f79f00
27 /*
28 * The VFP state has 32x64-bit registers and a single 32-bit
29 * control/status register.
30 */
31 #define VFP_STATE_SIZE ((32 * 8) + 4)
32
33 static inline unsigned long cpacr_save_enable_kernel_sve(void)
34 {
35 unsigned long old = read_sysreg(cpacr_el1);
36 unsigned long set = CPACR_EL1_FPEN_EL1EN | CPACR_EL1_ZEN_EL1EN;
37
38 write_sysreg(old | set, cpacr_el1);
39 isb();
40 return old;
41 }
42
43 static inline unsigned long cpacr_save_enable_kernel_sme(void)
44 {
45 unsigned long old = read_sysreg(cpacr_el1);
46 unsigned long set = CPACR_EL1_FPEN_EL1EN | CPACR_EL1_SMEN_EL1EN;
47
48 write_sysreg(old | set, cpacr_el1);
49 isb();
50 return old;
51 }
52
53 static inline void cpacr_restore(unsigned long cpacr)
54 {
55 write_sysreg(cpacr, cpacr_el1);
56 isb();
57 }
58
59 /*
60 * When we defined the maximum SVE vector length we defined the ABI so
61 * that the maximum vector length included all the reserved for future
62 * expansion bits in ZCR rather than those just currently defined by
63 * the architecture. Using this length to allocate worst size buffers
64 * results in excessively large allocations, and this effect is even
65 * more pronounced for SME due to ZA. Define more suitable VLs for
66 * these situations.
67 */
68 #define ARCH_SVE_VQ_MAX ((ZCR_ELx_LEN_MASK >> ZCR_ELx_LEN_SHIFT) + 1)
69 #define SME_VQ_MAX ((SMCR_ELx_LEN_MASK >> SMCR_ELx_LEN_SHIFT) + 1)
70
71 struct task_struct;
72
73 extern void fpsimd_save_state(struct user_fpsimd_state *state);
74 extern void fpsimd_load_state(struct user_fpsimd_state *state);
75
76 extern void fpsimd_thread_switch(struct task_struct *next);
77 extern void fpsimd_flush_thread(void);
78
79 extern void fpsimd_signal_preserve_current_state(void);
80 extern void fpsimd_preserve_current_state(void);
81 extern void fpsimd_restore_current_state(void);
82 extern void fpsimd_update_current_state(struct user_fpsimd_state const *state);
83 extern void fpsimd_kvm_prepare(void);
84
85 struct cpu_fp_state {
86 struct user_fpsimd_state *st;
87 void *sve_state;
88 void *sme_state;
89 u64 *svcr;
90 u64 *fpmr;
91 unsigned int sve_vl;
92 unsigned int sme_vl;
93 enum fp_type *fp_type;
94 enum fp_type to_save;
95 };
96
97 extern void fpsimd_bind_state_to_cpu(struct cpu_fp_state *fp_state);
98
99 extern void fpsimd_flush_task_state(struct task_struct *target);
100 extern void fpsimd_save_and_flush_cpu_state(void);
101
102 static inline bool thread_sm_enabled(struct thread_struct *thread)
103 {
104 return system_supports_sme() && (thread->svcr & SVCR_SM_MASK);
105 }
106
107 static inline bool thread_za_enabled(struct thread_struct *thread)
108 {
109 return system_supports_sme() && (thread->svcr & SVCR_ZA_MASK);
110 }
111
112 /* Maximum VL that SVE/SME VL-agnostic software can transparently support */
113 #define VL_ARCH_MAX 0x100
114
115 /* Offset of FFR in the SVE register dump */
116 static inline size_t sve_ffr_offset(int vl)
117 {
118 return SVE_SIG_FFR_OFFSET(sve_vq_from_vl(vl)) - SVE_SIG_REGS_OFFSET;
119 }
120
121 static inline void *sve_pffr(struct thread_struct *thread)
122 {
123 unsigned int vl;
124
125 if (system_supports_sme() && thread_sm_enabled(thread))
126 vl = thread_get_sme_vl(thread);
127 else
128 vl = thread_get_sve_vl(thread);
129
130 return (char *)thread->sve_state + sve_ffr_offset(vl);
131 }
132
133 static inline void *thread_zt_state(struct thread_struct *thread)
134 {
135 /* The ZT register state is stored immediately after the ZA state */
136 unsigned int sme_vq = sve_vq_from_vl(thread_get_sme_vl(thread));
137 return thread->sme_state + ZA_SIG_REGS_SIZE(sme_vq);
138 }
139
140 extern void sve_save_state(void *state, u32 *pfpsr, int save_ffr);
141 extern void sve_load_state(void const *state, u32 const *pfpsr,
142 int restore_ffr);
143 extern void sve_flush_live(bool flush_ffr, unsigned long vq_minus_1);
144 extern unsigned int sve_get_vl(void);
145 extern void sve_set_vq(unsigned long vq_minus_1);
146 extern void sme_set_vq(unsigned long vq_minus_1);
147 extern void sme_save_state(void *state, int zt);
148 extern void sme_load_state(void const *state, int zt);
149
150 struct arm64_cpu_capabilities;
151 extern void cpu_enable_fpsimd(const struct arm64_cpu_capabilities *__unused);
152 extern void cpu_enable_sve(const struct arm64_cpu_capabilities *__unused);
153 extern void cpu_enable_sme(const struct arm64_cpu_capabilities *__unused);
154 extern void cpu_enable_sme2(const struct arm64_cpu_capabilities *__unused);
155 extern void cpu_enable_fa64(const struct arm64_cpu_capabilities *__unused);
156 extern void cpu_enable_fpmr(const struct arm64_cpu_capabilities *__unused);
157
158 extern u64 read_smcr_features(void);
159
160 /*
161 * Helpers to translate bit indices in sve_vq_map to VQ values (and
162 * vice versa). This allows find_next_bit() to be used to find the
163 * _maximum_ VQ not exceeding a certain value.
164 */
165 static inline unsigned int __vq_to_bit(unsigned int vq)
166 {
167 return SVE_VQ_MAX - vq;
168 }
169
170 static inline unsigned int __bit_to_vq(unsigned int bit)
171 {
172 return SVE_VQ_MAX - bit;
173 }
174
175
176 struct vl_info {
177 enum vec_type type;
178 const char *name; /* For display purposes */
179
180 /* Minimum supported vector length across all CPUs */
181 int min_vl;
182
183 /* Maximum supported vector length across all CPUs */
184 int max_vl;
185 int max_virtualisable_vl;
186
187 /*
188 * Set of available vector lengths,
189 * where length vq encoded as bit __vq_to_bit(vq):
190 */
191 DECLARE_BITMAP(vq_map, SVE_VQ_MAX);
192
193 /* Set of vector lengths present on at least one cpu: */
194 DECLARE_BITMAP(vq_partial_map, SVE_VQ_MAX);
195 };
196
197 #ifdef CONFIG_ARM64_SVE
198
199 extern void sve_alloc(struct task_struct *task, bool flush);
200 extern void fpsimd_release_task(struct task_struct *task);
201 extern void fpsimd_sync_to_sve(struct task_struct *task);
202 extern void fpsimd_force_sync_to_sve(struct task_struct *task);
203 extern void sve_sync_to_fpsimd(struct task_struct *task);
204 extern void sve_sync_from_fpsimd_zeropad(struct task_struct *task);
205
206 extern int vec_set_vector_length(struct task_struct *task, enum vec_type type,
207 unsigned long vl, unsigned long flags);
208
209 extern int sve_set_current_vl(unsigned long arg);
210 extern int sve_get_current_vl(void);
211
212 static inline void sve_user_disable(void)
213 {
214 sysreg_clear_set(cpacr_el1, CPACR_EL1_ZEN_EL0EN, 0);
215 }
216
217 static inline void sve_user_enable(void)
218 {
219 sysreg_clear_set(cpacr_el1, 0, CPACR_EL1_ZEN_EL0EN);
220 }
221
222 #define sve_cond_update_zcr_vq(val, reg) \
223 do { \
224 u64 __zcr = read_sysreg_s((reg)); \
225 u64 __new = __zcr & ~ZCR_ELx_LEN_MASK; \
226 __new |= (val) & ZCR_ELx_LEN_MASK; \
227 if (__zcr != __new) \
228 write_sysreg_s(__new, (reg)); \
229 } while (0)
230
231 /*
232 * Probing and setup functions.
233 * Calls to these functions must be serialised with one another.
234 */
235 enum vec_type;
236
237 extern void __init vec_init_vq_map(enum vec_type type);
238 extern void vec_update_vq_map(enum vec_type type);
239 extern int vec_verify_vq_map(enum vec_type type);
240 extern void __init sve_setup(void);
241
242 extern __ro_after_init struct vl_info vl_info[ARM64_VEC_MAX];
243
244 static inline void write_vl(enum vec_type type, u64 val)
245 {
246 u64 tmp;
247
248 switch (type) {
249 #ifdef CONFIG_ARM64_SVE
250 case ARM64_VEC_SVE:
251 tmp = read_sysreg_s(SYS_ZCR_EL1) & ~ZCR_ELx_LEN_MASK;
252 write_sysreg_s(tmp | val, SYS_ZCR_EL1);
253 break;
254 #endif
255 #ifdef CONFIG_ARM64_SME
256 case ARM64_VEC_SME:
257 tmp = read_sysreg_s(SYS_SMCR_EL1) & ~SMCR_ELx_LEN_MASK;
258 write_sysreg_s(tmp | val, SYS_SMCR_EL1);
259 break;
260 #endif
261 default:
262 WARN_ON_ONCE(1);
263 break;
264 }
265 }
266
267 static inline int vec_max_vl(enum vec_type type)
268 {
269 return vl_info[type].max_vl;
270 }
271
272 static inline int vec_max_virtualisable_vl(enum vec_type type)
273 {
274 return vl_info[type].max_virtualisable_vl;
275 }
276
277 static inline int sve_max_vl(void)
278 {
279 return vec_max_vl(ARM64_VEC_SVE);
280 }
281
282 static inline int sve_max_virtualisable_vl(void)
283 {
284 return vec_max_virtualisable_vl(ARM64_VEC_SVE);
285 }
286
287 /* Ensure vq >= SVE_VQ_MIN && vq <= SVE_VQ_MAX before calling this function */
288 static inline bool vq_available(enum vec_type type, unsigned int vq)
289 {
290 return test_bit(__vq_to_bit(vq), vl_info[type].vq_map);
291 }
292
293 static inline bool sve_vq_available(unsigned int vq)
294 {
295 return vq_available(ARM64_VEC_SVE, vq);
296 }
297
298 size_t sve_state_size(struct task_struct const *task);
299
300 #else /* ! CONFIG_ARM64_SVE */
301
302 static inline void sve_alloc(struct task_struct *task, bool flush) { }
303 static inline void fpsimd_release_task(struct task_struct *task) { }
304 static inline void sve_sync_to_fpsimd(struct task_struct *task) { }
305 static inline void sve_sync_from_fpsimd_zeropad(struct task_struct *task) { }
306
307 static inline int sve_max_virtualisable_vl(void)
308 {
309 return 0;
310 }
311
312 static inline int sve_set_current_vl(unsigned long arg)
313 {
314 return -EINVAL;
315 }
316
317 static inline int sve_get_current_vl(void)
318 {
319 return -EINVAL;
320 }
321
322 static inline int sve_max_vl(void)
323 {
324 return -EINVAL;
325 }
326
327 static inline bool sve_vq_available(unsigned int vq) { return false; }
328
329 static inline void sve_user_disable(void) { BUILD_BUG(); }
330 static inline void sve_user_enable(void) { BUILD_BUG(); }
331
332 #define sve_cond_update_zcr_vq(val, reg) do { } while (0)
333
334 static inline void vec_init_vq_map(enum vec_type t) { }
335 static inline void vec_update_vq_map(enum vec_type t) { }
336 static inline int vec_verify_vq_map(enum vec_type t) { return 0; }
337 static inline void sve_setup(void) { }
338
339 static inline size_t sve_state_size(struct task_struct const *task)
340 {
341 return 0;
342 }
343
344 #endif /* ! CONFIG_ARM64_SVE */
345
346 #ifdef CONFIG_ARM64_SME
347
348 static inline void sme_user_disable(void)
349 {
350 sysreg_clear_set(cpacr_el1, CPACR_EL1_SMEN_EL0EN, 0);
351 }
352
353 static inline void sme_user_enable(void)
354 {
355 sysreg_clear_set(cpacr_el1, 0, CPACR_EL1_SMEN_EL0EN);
356 }
357
358 static inline void sme_smstart_sm(void)
359 {
360 asm volatile(__msr_s(SYS_SVCR_SMSTART_SM_EL0, "xzr"));
361 }
362
363 static inline void sme_smstop_sm(void)
364 {
365 asm volatile(__msr_s(SYS_SVCR_SMSTOP_SM_EL0, "xzr"));
366 }
367
368 static inline void sme_smstop(void)
369 {
370 asm volatile(__msr_s(SYS_SVCR_SMSTOP_SMZA_EL0, "xzr"));
371 }
372
373 extern void __init sme_setup(void);
374
375 static inline int sme_max_vl(void)
376 {
377 return vec_max_vl(ARM64_VEC_SME);
378 }
379
380 static inline int sme_max_virtualisable_vl(void)
381 {
382 return vec_max_virtualisable_vl(ARM64_VEC_SME);
383 }
384
385 extern void sme_alloc(struct task_struct *task, bool flush);
386 extern unsigned int sme_get_vl(void);
387 extern int sme_set_current_vl(unsigned long arg);
388 extern int sme_get_current_vl(void);
389 extern void sme_suspend_exit(void);
390
391 /*
392 * Return how many bytes of memory are required to store the full SME
393 * specific state for task, given task's currently configured vector
394 * length.
395 */
396 static inline size_t sme_state_size(struct task_struct const *task)
397 {
398 unsigned int vl = task_get_sme_vl(task);
399 size_t size;
400
401 size = ZA_SIG_REGS_SIZE(sve_vq_from_vl(vl));
402
403 if (system_supports_sme2())
404 size += ZT_SIG_REG_SIZE;
405
406 return size;
407 }
408
409 #else
410
411 static inline void sme_user_disable(void) { BUILD_BUG(); }
412 static inline void sme_user_enable(void) { BUILD_BUG(); }
413
414 static inline void sme_smstart_sm(void) { }
415 static inline void sme_smstop_sm(void) { }
416 static inline void sme_smstop(void) { }
417
418 static inline void sme_alloc(struct task_struct *task, bool flush) { }
419 static inline void sme_setup(void) { }
420 static inline unsigned int sme_get_vl(void) { return 0; }
421 static inline int sme_max_vl(void) { return 0; }
422 static inline int sme_max_virtualisable_vl(void) { return 0; }
423 static inline int sme_set_current_vl(unsigned long arg) { return -EINVAL; }
424 static inline int sme_get_current_vl(void) { return -EINVAL; }
425 static inline void sme_suspend_exit(void) { }
426
427 static inline size_t sme_state_size(struct task_struct const *task)
428 {
429 return 0;
430 }
431
432 #endif /* ! CONFIG_ARM64_SME */
433
434 /* For use by EFI runtime services calls only */
435 extern void __efi_fpsimd_begin(void);
436 extern void __efi_fpsimd_end(void);
437
438 #endif
439
440 #endif
441
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