1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Interrupt request handling routines. On the
4 * Sparc the IRQs are basically 'cast in stone'
5 * and you are supposed to probe the prom's device
6 * node trees to find out who's got which IRQ.
7 *
8 * Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
9 * Copyright (C) 1995 Miguel de Icaza (miguel@nuclecu.unam.mx)
10 * Copyright (C) 1995,2002 Pete A. Zaitcev (zaitcev@yahoo.com)
11 * Copyright (C) 1996 Dave Redman (djhr@tadpole.co.uk)
12 * Copyright (C) 1998-2000 Anton Blanchard (anton@samba.org)
13 */
14
15 #include <linux/kernel_stat.h>
16 #include <linux/seq_file.h>
17 #include <linux/export.h>
18
19 #include <asm/cacheflush.h>
20 #include <asm/cpudata.h>
21 #include <asm/setup.h>
22 #include <asm/pcic.h>
23 #include <asm/leon.h>
24
25 #include "kernel.h"
26 #include "irq.h"
27
28 /* platform specific irq setup */
29 struct sparc_config sparc_config;
30
31 unsigned long arch_local_irq_save(void)
32 {
33 unsigned long retval;
34 unsigned long tmp;
35
36 __asm__ __volatile__(
37 "rd %%psr, %0\n\t"
38 "or %0, %2, %1\n\t"
39 "wr %1, 0, %%psr\n\t"
40 "nop; nop; nop\n"
41 : "=&r" (retval), "=r" (tmp)
42 : "i" (PSR_PIL)
43 : "memory");
44
45 return retval;
46 }
47 EXPORT_SYMBOL(arch_local_irq_save);
48
49 void arch_local_irq_enable(void)
50 {
51 unsigned long tmp;
52
53 __asm__ __volatile__(
54 "rd %%psr, %0\n\t"
55 "andn %0, %1, %0\n\t"
56 "wr %0, 0, %%psr\n\t"
57 "nop; nop; nop\n"
58 : "=&r" (tmp)
59 : "i" (PSR_PIL)
60 : "memory");
61 }
62 EXPORT_SYMBOL(arch_local_irq_enable);
63
64 void arch_local_irq_restore(unsigned long old_psr)
65 {
66 unsigned long tmp;
67
68 __asm__ __volatile__(
69 "rd %%psr, %0\n\t"
70 "and %2, %1, %2\n\t"
71 "andn %0, %1, %0\n\t"
72 "wr %0, %2, %%psr\n\t"
73 "nop; nop; nop\n"
74 : "=&r" (tmp)
75 : "i" (PSR_PIL), "r" (old_psr)
76 : "memory");
77 }
78 EXPORT_SYMBOL(arch_local_irq_restore);
79
80 /*
81 * Dave Redman (djhr@tadpole.co.uk)
82 *
83 * IRQ numbers.. These are no longer restricted to 15..
84 *
85 * this is done to enable SBUS cards and onboard IO to be masked
86 * correctly. using the interrupt level isn't good enough.
87 *
88 * For example:
89 * A device interrupting at sbus level6 and the Floppy both come in
90 * at IRQ11, but enabling and disabling them requires writing to
91 * different bits in the SLAVIO/SEC.
92 *
93 * As a result of these changes sun4m machines could now support
94 * directed CPU interrupts using the existing enable/disable irq code
95 * with tweaks.
96 *
97 * Sun4d complicates things even further. IRQ numbers are arbitrary
98 * 32-bit values in that case. Since this is similar to sparc64,
99 * we adopt a virtual IRQ numbering scheme as is done there.
100 * Virutal interrupt numbers are allocated by build_irq(). So NR_IRQS
101 * just becomes a limit of how many interrupt sources we can handle in
102 * a single system. Even fully loaded SS2000 machines top off at
103 * about 32 interrupt sources or so, therefore a NR_IRQS value of 64
104 * is more than enough.
105 *
106 * We keep a map of per-PIL enable interrupts. These get wired
107 * up via the irq_chip->startup() method which gets invoked by
108 * the generic IRQ layer during request_irq().
109 */
110
111
112 /* Table of allocated irqs. Unused entries has irq == 0 */
113 static struct irq_bucket irq_table[NR_IRQS];
114 /* Protect access to irq_table */
115 static DEFINE_SPINLOCK(irq_table_lock);
116
117 /* Map between the irq identifier used in hw to the irq_bucket. */
118 struct irq_bucket *irq_map[SUN4D_MAX_IRQ];
119 /* Protect access to irq_map */
120 static DEFINE_SPINLOCK(irq_map_lock);
121
122 /* Allocate a new irq from the irq_table */
123 unsigned int irq_alloc(unsigned int real_irq, unsigned int pil)
124 {
125 unsigned long flags;
126 unsigned int i;
127
128 spin_lock_irqsave(&irq_table_lock, flags);
129 for (i = 1; i < NR_IRQS; i++) {
130 if (irq_table[i].real_irq == real_irq && irq_table[i].pil == pil)
131 goto found;
132 }
133
134 for (i = 1; i < NR_IRQS; i++) {
135 if (!irq_table[i].irq)
136 break;
137 }
138
139 if (i < NR_IRQS) {
140 irq_table[i].real_irq = real_irq;
141 irq_table[i].irq = i;
142 irq_table[i].pil = pil;
143 } else {
144 printk(KERN_ERR "IRQ: Out of virtual IRQs.\n");
145 i = 0;
146 }
147 found:
148 spin_unlock_irqrestore(&irq_table_lock, flags);
149
150 return i;
151 }
152
153 /* Based on a single pil handler_irq may need to call several
154 * interrupt handlers. Use irq_map as entry to irq_table,
155 * and let each entry in irq_table point to the next entry.
156 */
157 void irq_link(unsigned int irq)
158 {
159 struct irq_bucket *p;
160 unsigned long flags;
161 unsigned int pil;
162
163 BUG_ON(irq >= NR_IRQS);
164
165 spin_lock_irqsave(&irq_map_lock, flags);
166
167 p = &irq_table[irq];
168 pil = p->pil;
169 BUG_ON(pil >= SUN4D_MAX_IRQ);
170 p->next = irq_map[pil];
171 irq_map[pil] = p;
172
173 spin_unlock_irqrestore(&irq_map_lock, flags);
174 }
175
176 void irq_unlink(unsigned int irq)
177 {
178 struct irq_bucket *p, **pnext;
179 unsigned long flags;
180
181 BUG_ON(irq >= NR_IRQS);
182
183 spin_lock_irqsave(&irq_map_lock, flags);
184
185 p = &irq_table[irq];
186 BUG_ON(p->pil >= SUN4D_MAX_IRQ);
187 pnext = &irq_map[p->pil];
188 while (*pnext != p)
189 pnext = &(*pnext)->next;
190 *pnext = p->next;
191
192 spin_unlock_irqrestore(&irq_map_lock, flags);
193 }
194
195
196 /* /proc/interrupts printing */
197 int arch_show_interrupts(struct seq_file *p, int prec)
198 {
199 int j;
200
201 #ifdef CONFIG_SMP
202 seq_printf(p, "RES: ");
203 for_each_online_cpu(j)
204 seq_printf(p, "%10u ", cpu_data(j).irq_resched_count);
205 seq_printf(p, " IPI rescheduling interrupts\n");
206 seq_printf(p, "CAL: ");
207 for_each_online_cpu(j)
208 seq_printf(p, "%10u ", cpu_data(j).irq_call_count);
209 seq_printf(p, " IPI function call interrupts\n");
210 #endif
211 seq_printf(p, "NMI: ");
212 for_each_online_cpu(j)
213 seq_printf(p, "%10u ", cpu_data(j).counter);
214 seq_printf(p, " Non-maskable interrupts\n");
215 return 0;
216 }
217
218 void handler_irq(unsigned int pil, struct pt_regs *regs)
219 {
220 struct pt_regs *old_regs;
221 struct irq_bucket *p;
222
223 BUG_ON(pil > 15);
224 old_regs = set_irq_regs(regs);
225 irq_enter();
226
227 p = irq_map[pil];
228 while (p) {
229 struct irq_bucket *next = p->next;
230
231 generic_handle_irq(p->irq);
232 p = next;
233 }
234 irq_exit();
235 set_irq_regs(old_regs);
236 }
237
238 #if defined(CONFIG_BLK_DEV_FD) || defined(CONFIG_BLK_DEV_FD_MODULE)
239 static unsigned int floppy_irq;
240
241 int sparc_floppy_request_irq(unsigned int irq, irq_handler_t irq_handler)
242 {
243 unsigned int cpu_irq;
244 int err;
245
246
247 err = request_irq(irq, irq_handler, 0, "floppy", NULL);
248 if (err)
249 return -1;
250
251 /* Save for later use in floppy interrupt handler */
252 floppy_irq = irq;
253
254 cpu_irq = (irq & (NR_IRQS - 1));
255
256 /* Dork with trap table if we get this far. */
257 #define INSTANTIATE(table) \
258 table[SP_TRAP_IRQ1+(cpu_irq-1)].inst_one = SPARC_RD_PSR_L0; \
259 table[SP_TRAP_IRQ1+(cpu_irq-1)].inst_two = \
260 SPARC_BRANCH((unsigned long) floppy_hardint, \
261 (unsigned long) &table[SP_TRAP_IRQ1+(cpu_irq-1)].inst_two);\
262 table[SP_TRAP_IRQ1+(cpu_irq-1)].inst_three = SPARC_RD_WIM_L3; \
263 table[SP_TRAP_IRQ1+(cpu_irq-1)].inst_four = SPARC_NOP;
264
265 INSTANTIATE(sparc_ttable)
266
267 #if defined CONFIG_SMP
268 if (sparc_cpu_model != sparc_leon) {
269 struct tt_entry *trap_table;
270
271 trap_table = &trapbase_cpu1[0];
272 INSTANTIATE(trap_table)
273 trap_table = &trapbase_cpu2[0];
274 INSTANTIATE(trap_table)
275 trap_table = &trapbase_cpu3[0];
276 INSTANTIATE(trap_table)
277 }
278 #endif
279 #undef INSTANTIATE
280 /*
281 * XXX Correct thing whould be to flush only I- and D-cache lines
282 * which contain the handler in question. But as of time of the
283 * writing we have no CPU-neutral interface to fine-grained flushes.
284 */
285 flush_cache_all();
286 return 0;
287 }
288 EXPORT_SYMBOL(sparc_floppy_request_irq);
289
290 /*
291 * These variables are used to access state from the assembler
292 * interrupt handler, floppy_hardint, so we cannot put these in
293 * the floppy driver image because that would not work in the
294 * modular case.
295 */
296 volatile unsigned char *fdc_status;
297 EXPORT_SYMBOL(fdc_status);
298
299 char *pdma_vaddr;
300 EXPORT_SYMBOL(pdma_vaddr);
301
302 unsigned long pdma_size;
303 EXPORT_SYMBOL(pdma_size);
304
305 volatile int doing_pdma;
306 EXPORT_SYMBOL(doing_pdma);
307
308 char *pdma_base;
309 EXPORT_SYMBOL(pdma_base);
310
311 unsigned long pdma_areasize;
312 EXPORT_SYMBOL(pdma_areasize);
313
314 /* Use the generic irq support to call floppy_interrupt
315 * which was setup using request_irq() in sparc_floppy_request_irq().
316 * We only have one floppy interrupt so we do not need to check
317 * for additional handlers being wired up by irq_link()
318 */
319 void sparc_floppy_irq(int irq, void *dev_id, struct pt_regs *regs)
320 {
321 struct pt_regs *old_regs;
322
323 old_regs = set_irq_regs(regs);
324 irq_enter();
325 generic_handle_irq(floppy_irq);
326 irq_exit();
327 set_irq_regs(old_regs);
328 }
329 #endif
330
331 /* djhr
332 * This could probably be made indirect too and assigned in the CPU
333 * bits of the code. That would be much nicer I think and would also
334 * fit in with the idea of being able to tune your kernel for your machine
335 * by removing unrequired machine and device support.
336 *
337 */
338
339 void __init init_IRQ(void)
340 {
341 switch (sparc_cpu_model) {
342 case sun4m:
343 pcic_probe();
344 if (pcic_present())
345 sun4m_pci_init_IRQ();
346 else
347 sun4m_init_IRQ();
348 break;
349
350 case sun4d:
351 sun4d_init_IRQ();
352 break;
353
354 case sparc_leon:
355 leon_init_IRQ();
356 break;
357
358 default:
359 prom_printf("Cannot initialize IRQs on this Sun machine...");
360 break;
361 }
362 }
363
364
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