1/*
2 * This file is subject to the terms and conditions of the GNU General Public
3 * License. See the file "COPYING" in the main directory of this archive
4 * for more details.
5 *
6 * Copyright (C) 2008 Maxime Bizon <mbizon@freebox.fr>
7 * Copyright (C) 2008 Nicolas Schichan <nschichan@freebox.fr>
8 */
9
10#include <linux/kernel.h>
11#include <linux/init.h>
12#include <linux/interrupt.h>
13#include <linux/irq.h>
14#include <linux/spinlock.h>
15#include <asm/irq_cpu.h>
16#include <asm/mipsregs.h>
17#include <bcm63xx_cpu.h>
18#include <bcm63xx_regs.h>
19#include <bcm63xx_io.h>
20#include <bcm63xx_irq.h>
21
22
23static DEFINE_SPINLOCK(ipic_lock);
24static DEFINE_SPINLOCK(epic_lock);
25
26static u32 irq_stat_addr[2];
27static u32 irq_mask_addr[2];
28static void (*dispatch_internal)(int cpu);
29static int is_ext_irq_cascaded;
30static unsigned int ext_irq_count;
31static unsigned int ext_irq_start, ext_irq_end;
32static unsigned int ext_irq_cfg_reg1, ext_irq_cfg_reg2;
33static void (*internal_irq_mask)(struct irq_data *d);
34static void (*internal_irq_unmask)(struct irq_data *d, const struct cpumask *m);
35
36
37static inline u32 get_ext_irq_perf_reg(int irq)
38{
39 if (irq < 4)
40 return ext_irq_cfg_reg1;
41 return ext_irq_cfg_reg2;
42}
43
44static inline void handle_internal(int intbit)
45{
46 if (is_ext_irq_cascaded &&
47 intbit >= ext_irq_start && intbit <= ext_irq_end)
48 do_IRQ(intbit - ext_irq_start + IRQ_EXTERNAL_BASE);
49 else
50 do_IRQ(intbit + IRQ_INTERNAL_BASE);
51}
52
53static inline int enable_irq_for_cpu(int cpu, struct irq_data *d,
54 const struct cpumask *m)
55{
56 bool enable = cpu_online(cpu);
57
58#ifdef CONFIG_SMP
59 if (m)
60 enable &= cpumask_test_cpu(cpu, cpumask: m);
61 else if (irqd_affinity_was_set(d))
62 enable &= cpumask_test_cpu(cpu, cpumask: irq_data_get_affinity_mask(d));
63#endif
64 return enable;
65}
66
67/*
68 * dispatch internal devices IRQ (uart, enet, watchdog, ...). do not
69 * prioritize any interrupt relatively to another. the static counter
70 * will resume the loop where it ended the last time we left this
71 * function.
72 */
73
74#define BUILD_IPIC_INTERNAL(width) \
75static void __dispatch_internal_##width(int cpu) \
76{ \
77 u32 pending[width / 32]; \
78 unsigned int src, tgt; \
79 bool irqs_pending = false; \
80 static unsigned int i[2]; \
81 unsigned int *next = &i[cpu]; \
82 unsigned long flags; \
83 \
84 /* read registers in reverse order */ \
85 spin_lock_irqsave(&ipic_lock, flags); \
86 for (src = 0, tgt = (width / 32); src < (width / 32); src++) { \
87 u32 val; \
88 \
89 val = bcm_readl(irq_stat_addr[cpu] + src * sizeof(u32)); \
90 val &= bcm_readl(irq_mask_addr[cpu] + src * sizeof(u32)); \
91 pending[--tgt] = val; \
92 \
93 if (val) \
94 irqs_pending = true; \
95 } \
96 spin_unlock_irqrestore(&ipic_lock, flags); \
97 \
98 if (!irqs_pending) \
99 return; \
100 \
101 while (1) { \
102 unsigned int to_call = *next; \
103 \
104 *next = (*next + 1) & (width - 1); \
105 if (pending[to_call / 32] & (1 << (to_call & 0x1f))) { \
106 handle_internal(to_call); \
107 break; \
108 } \
109 } \
110} \
111 \
112static void __internal_irq_mask_##width(struct irq_data *d) \
113{ \
114 u32 val; \
115 unsigned irq = d->irq - IRQ_INTERNAL_BASE; \
116 unsigned reg = (irq / 32) ^ (width/32 - 1); \
117 unsigned bit = irq & 0x1f; \
118 unsigned long flags; \
119 int cpu; \
120 \
121 spin_lock_irqsave(&ipic_lock, flags); \
122 for_each_present_cpu(cpu) { \
123 if (!irq_mask_addr[cpu]) \
124 break; \
125 \
126 val = bcm_readl(irq_mask_addr[cpu] + reg * sizeof(u32));\
127 val &= ~(1 << bit); \
128 bcm_writel(val, irq_mask_addr[cpu] + reg * sizeof(u32));\
129 } \
130 spin_unlock_irqrestore(&ipic_lock, flags); \
131} \
132 \
133static void __internal_irq_unmask_##width(struct irq_data *d, \
134 const struct cpumask *m) \
135{ \
136 u32 val; \
137 unsigned irq = d->irq - IRQ_INTERNAL_BASE; \
138 unsigned reg = (irq / 32) ^ (width/32 - 1); \
139 unsigned bit = irq & 0x1f; \
140 unsigned long flags; \
141 int cpu; \
142 \
143 spin_lock_irqsave(&ipic_lock, flags); \
144 for_each_present_cpu(cpu) { \
145 if (!irq_mask_addr[cpu]) \
146 break; \
147 \
148 val = bcm_readl(irq_mask_addr[cpu] + reg * sizeof(u32));\
149 if (enable_irq_for_cpu(cpu, d, m)) \
150 val |= (1 << bit); \
151 else \
152 val &= ~(1 << bit); \
153 bcm_writel(val, irq_mask_addr[cpu] + reg * sizeof(u32));\
154 } \
155 spin_unlock_irqrestore(&ipic_lock, flags); \
156}
157
158BUILD_IPIC_INTERNAL(32);
159BUILD_IPIC_INTERNAL(64);
160
161asmlinkage void plat_irq_dispatch(void)
162{
163 u32 cause;
164
165 do {
166 cause = read_c0_cause() & read_c0_status() & ST0_IM;
167
168 if (!cause)
169 break;
170
171 if (cause & CAUSEF_IP7)
172 do_IRQ(7);
173 if (cause & CAUSEF_IP0)
174 do_IRQ(0);
175 if (cause & CAUSEF_IP1)
176 do_IRQ(1);
177 if (cause & CAUSEF_IP2)
178 dispatch_internal(0);
179 if (is_ext_irq_cascaded) {
180 if (cause & CAUSEF_IP3)
181 dispatch_internal(1);
182 } else {
183 if (cause & CAUSEF_IP3)
184 do_IRQ(IRQ_EXT_0);
185 if (cause & CAUSEF_IP4)
186 do_IRQ(IRQ_EXT_1);
187 if (cause & CAUSEF_IP5)
188 do_IRQ(IRQ_EXT_2);
189 if (cause & CAUSEF_IP6)
190 do_IRQ(IRQ_EXT_3);
191 }
192 } while (1);
193}
194
195/*
196 * internal IRQs operations: only mask/unmask on PERF irq mask
197 * register.
198 */
199static void bcm63xx_internal_irq_mask(struct irq_data *d)
200{
201 internal_irq_mask(d);
202}
203
204static void bcm63xx_internal_irq_unmask(struct irq_data *d)
205{
206 internal_irq_unmask(d, NULL);
207}
208
209/*
210 * external IRQs operations: mask/unmask and clear on PERF external
211 * irq control register.
212 */
213static void bcm63xx_external_irq_mask(struct irq_data *d)
214{
215 unsigned int irq = d->irq - IRQ_EXTERNAL_BASE;
216 u32 reg, regaddr;
217 unsigned long flags;
218
219 regaddr = get_ext_irq_perf_reg(irq);
220 spin_lock_irqsave(&epic_lock, flags);
221 reg = bcm_perf_readl(regaddr);
222
223 if (BCMCPU_IS_6348())
224 reg &= ~EXTIRQ_CFG_MASK_6348(irq % 4);
225 else
226 reg &= ~EXTIRQ_CFG_MASK(irq % 4);
227
228 bcm_perf_writel(reg, regaddr);
229 spin_unlock_irqrestore(lock: &epic_lock, flags);
230
231 if (is_ext_irq_cascaded)
232 internal_irq_mask(irq_get_irq_data(irq: irq + ext_irq_start));
233}
234
235static void bcm63xx_external_irq_unmask(struct irq_data *d)
236{
237 unsigned int irq = d->irq - IRQ_EXTERNAL_BASE;
238 u32 reg, regaddr;
239 unsigned long flags;
240
241 regaddr = get_ext_irq_perf_reg(irq);
242 spin_lock_irqsave(&epic_lock, flags);
243 reg = bcm_perf_readl(regaddr);
244
245 if (BCMCPU_IS_6348())
246 reg |= EXTIRQ_CFG_MASK_6348(irq % 4);
247 else
248 reg |= EXTIRQ_CFG_MASK(irq % 4);
249
250 bcm_perf_writel(reg, regaddr);
251 spin_unlock_irqrestore(lock: &epic_lock, flags);
252
253 if (is_ext_irq_cascaded)
254 internal_irq_unmask(irq_get_irq_data(irq: irq + ext_irq_start),
255 NULL);
256}
257
258static void bcm63xx_external_irq_clear(struct irq_data *d)
259{
260 unsigned int irq = d->irq - IRQ_EXTERNAL_BASE;
261 u32 reg, regaddr;
262 unsigned long flags;
263
264 regaddr = get_ext_irq_perf_reg(irq);
265 spin_lock_irqsave(&epic_lock, flags);
266 reg = bcm_perf_readl(regaddr);
267
268 if (BCMCPU_IS_6348())
269 reg |= EXTIRQ_CFG_CLEAR_6348(irq % 4);
270 else
271 reg |= EXTIRQ_CFG_CLEAR(irq % 4);
272
273 bcm_perf_writel(reg, regaddr);
274 spin_unlock_irqrestore(lock: &epic_lock, flags);
275}
276
277static int bcm63xx_external_irq_set_type(struct irq_data *d,
278 unsigned int flow_type)
279{
280 unsigned int irq = d->irq - IRQ_EXTERNAL_BASE;
281 u32 reg, regaddr;
282 int levelsense, sense, bothedge;
283 unsigned long flags;
284
285 flow_type &= IRQ_TYPE_SENSE_MASK;
286
287 if (flow_type == IRQ_TYPE_NONE)
288 flow_type = IRQ_TYPE_LEVEL_LOW;
289
290 levelsense = sense = bothedge = 0;
291 switch (flow_type) {
292 case IRQ_TYPE_EDGE_BOTH:
293 bothedge = 1;
294 break;
295
296 case IRQ_TYPE_EDGE_RISING:
297 sense = 1;
298 break;
299
300 case IRQ_TYPE_EDGE_FALLING:
301 break;
302
303 case IRQ_TYPE_LEVEL_HIGH:
304 levelsense = 1;
305 sense = 1;
306 break;
307
308 case IRQ_TYPE_LEVEL_LOW:
309 levelsense = 1;
310 break;
311
312 default:
313 pr_err("bogus flow type combination given !\n");
314 return -EINVAL;
315 }
316
317 regaddr = get_ext_irq_perf_reg(irq);
318 spin_lock_irqsave(&epic_lock, flags);
319 reg = bcm_perf_readl(regaddr);
320 irq %= 4;
321
322 switch (bcm63xx_get_cpu_id()) {
323 case BCM6348_CPU_ID:
324 if (levelsense)
325 reg |= EXTIRQ_CFG_LEVELSENSE_6348(irq);
326 else
327 reg &= ~EXTIRQ_CFG_LEVELSENSE_6348(irq);
328 if (sense)
329 reg |= EXTIRQ_CFG_SENSE_6348(irq);
330 else
331 reg &= ~EXTIRQ_CFG_SENSE_6348(irq);
332 if (bothedge)
333 reg |= EXTIRQ_CFG_BOTHEDGE_6348(irq);
334 else
335 reg &= ~EXTIRQ_CFG_BOTHEDGE_6348(irq);
336 break;
337
338 case BCM3368_CPU_ID:
339 case BCM6328_CPU_ID:
340 case BCM6338_CPU_ID:
341 case BCM6345_CPU_ID:
342 case BCM6358_CPU_ID:
343 case BCM6362_CPU_ID:
344 case BCM6368_CPU_ID:
345 if (levelsense)
346 reg |= EXTIRQ_CFG_LEVELSENSE(irq);
347 else
348 reg &= ~EXTIRQ_CFG_LEVELSENSE(irq);
349 if (sense)
350 reg |= EXTIRQ_CFG_SENSE(irq);
351 else
352 reg &= ~EXTIRQ_CFG_SENSE(irq);
353 if (bothedge)
354 reg |= EXTIRQ_CFG_BOTHEDGE(irq);
355 else
356 reg &= ~EXTIRQ_CFG_BOTHEDGE(irq);
357 break;
358 default:
359 BUG();
360 }
361
362 bcm_perf_writel(reg, regaddr);
363 spin_unlock_irqrestore(lock: &epic_lock, flags);
364
365 irqd_set_trigger_type(d, type: flow_type);
366 if (flow_type & (IRQ_TYPE_LEVEL_LOW | IRQ_TYPE_LEVEL_HIGH))
367 irq_set_handler_locked(data: d, handler: handle_level_irq);
368 else
369 irq_set_handler_locked(data: d, handler: handle_edge_irq);
370
371 return IRQ_SET_MASK_OK_NOCOPY;
372}
373
374#ifdef CONFIG_SMP
375static int bcm63xx_internal_set_affinity(struct irq_data *data,
376 const struct cpumask *dest,
377 bool force)
378{
379 if (!irqd_irq_disabled(d: data))
380 internal_irq_unmask(data, dest);
381
382 return 0;
383}
384#endif
385
386static struct irq_chip bcm63xx_internal_irq_chip = {
387 .name = "bcm63xx_ipic",
388 .irq_mask = bcm63xx_internal_irq_mask,
389 .irq_unmask = bcm63xx_internal_irq_unmask,
390};
391
392static struct irq_chip bcm63xx_external_irq_chip = {
393 .name = "bcm63xx_epic",
394 .irq_ack = bcm63xx_external_irq_clear,
395
396 .irq_mask = bcm63xx_external_irq_mask,
397 .irq_unmask = bcm63xx_external_irq_unmask,
398
399 .irq_set_type = bcm63xx_external_irq_set_type,
400};
401
402static void bcm63xx_init_irq(void)
403{
404 int irq_bits;
405
406 irq_stat_addr[0] = bcm63xx_regset_address(RSET_PERF);
407 irq_mask_addr[0] = bcm63xx_regset_address(RSET_PERF);
408 irq_stat_addr[1] = bcm63xx_regset_address(RSET_PERF);
409 irq_mask_addr[1] = bcm63xx_regset_address(RSET_PERF);
410
411 switch (bcm63xx_get_cpu_id()) {
412 case BCM3368_CPU_ID:
413 irq_stat_addr[0] += PERF_IRQSTAT_3368_REG;
414 irq_mask_addr[0] += PERF_IRQMASK_3368_REG;
415 irq_stat_addr[1] = 0;
416 irq_mask_addr[1] = 0;
417 irq_bits = 32;
418 ext_irq_count = 4;
419 ext_irq_cfg_reg1 = PERF_EXTIRQ_CFG_REG_3368;
420 break;
421 case BCM6328_CPU_ID:
422 irq_stat_addr[0] += PERF_IRQSTAT_6328_REG(0);
423 irq_mask_addr[0] += PERF_IRQMASK_6328_REG(0);
424 irq_stat_addr[1] += PERF_IRQSTAT_6328_REG(1);
425 irq_mask_addr[1] += PERF_IRQMASK_6328_REG(1);
426 irq_bits = 64;
427 ext_irq_count = 4;
428 is_ext_irq_cascaded = 1;
429 ext_irq_start = BCM_6328_EXT_IRQ0 - IRQ_INTERNAL_BASE;
430 ext_irq_end = BCM_6328_EXT_IRQ3 - IRQ_INTERNAL_BASE;
431 ext_irq_cfg_reg1 = PERF_EXTIRQ_CFG_REG_6328;
432 break;
433 case BCM6338_CPU_ID:
434 irq_stat_addr[0] += PERF_IRQSTAT_6338_REG;
435 irq_mask_addr[0] += PERF_IRQMASK_6338_REG;
436 irq_stat_addr[1] = 0;
437 irq_mask_addr[1] = 0;
438 irq_bits = 32;
439 ext_irq_count = 4;
440 ext_irq_cfg_reg1 = PERF_EXTIRQ_CFG_REG_6338;
441 break;
442 case BCM6345_CPU_ID:
443 irq_stat_addr[0] += PERF_IRQSTAT_6345_REG;
444 irq_mask_addr[0] += PERF_IRQMASK_6345_REG;
445 irq_stat_addr[1] = 0;
446 irq_mask_addr[1] = 0;
447 irq_bits = 32;
448 ext_irq_count = 4;
449 ext_irq_cfg_reg1 = PERF_EXTIRQ_CFG_REG_6345;
450 break;
451 case BCM6348_CPU_ID:
452 irq_stat_addr[0] += PERF_IRQSTAT_6348_REG;
453 irq_mask_addr[0] += PERF_IRQMASK_6348_REG;
454 irq_stat_addr[1] = 0;
455 irq_mask_addr[1] = 0;
456 irq_bits = 32;
457 ext_irq_count = 4;
458 ext_irq_cfg_reg1 = PERF_EXTIRQ_CFG_REG_6348;
459 break;
460 case BCM6358_CPU_ID:
461 irq_stat_addr[0] += PERF_IRQSTAT_6358_REG(0);
462 irq_mask_addr[0] += PERF_IRQMASK_6358_REG(0);
463 irq_stat_addr[1] += PERF_IRQSTAT_6358_REG(1);
464 irq_mask_addr[1] += PERF_IRQMASK_6358_REG(1);
465 irq_bits = 32;
466 ext_irq_count = 4;
467 is_ext_irq_cascaded = 1;
468 ext_irq_start = BCM_6358_EXT_IRQ0 - IRQ_INTERNAL_BASE;
469 ext_irq_end = BCM_6358_EXT_IRQ3 - IRQ_INTERNAL_BASE;
470 ext_irq_cfg_reg1 = PERF_EXTIRQ_CFG_REG_6358;
471 break;
472 case BCM6362_CPU_ID:
473 irq_stat_addr[0] += PERF_IRQSTAT_6362_REG(0);
474 irq_mask_addr[0] += PERF_IRQMASK_6362_REG(0);
475 irq_stat_addr[1] += PERF_IRQSTAT_6362_REG(1);
476 irq_mask_addr[1] += PERF_IRQMASK_6362_REG(1);
477 irq_bits = 64;
478 ext_irq_count = 4;
479 is_ext_irq_cascaded = 1;
480 ext_irq_start = BCM_6362_EXT_IRQ0 - IRQ_INTERNAL_BASE;
481 ext_irq_end = BCM_6362_EXT_IRQ3 - IRQ_INTERNAL_BASE;
482 ext_irq_cfg_reg1 = PERF_EXTIRQ_CFG_REG_6362;
483 break;
484 case BCM6368_CPU_ID:
485 irq_stat_addr[0] += PERF_IRQSTAT_6368_REG(0);
486 irq_mask_addr[0] += PERF_IRQMASK_6368_REG(0);
487 irq_stat_addr[1] += PERF_IRQSTAT_6368_REG(1);
488 irq_mask_addr[1] += PERF_IRQMASK_6368_REG(1);
489 irq_bits = 64;
490 ext_irq_count = 6;
491 is_ext_irq_cascaded = 1;
492 ext_irq_start = BCM_6368_EXT_IRQ0 - IRQ_INTERNAL_BASE;
493 ext_irq_end = BCM_6368_EXT_IRQ5 - IRQ_INTERNAL_BASE;
494 ext_irq_cfg_reg1 = PERF_EXTIRQ_CFG_REG_6368;
495 ext_irq_cfg_reg2 = PERF_EXTIRQ_CFG_REG2_6368;
496 break;
497 default:
498 BUG();
499 }
500
501 if (irq_bits == 32) {
502 dispatch_internal = __dispatch_internal_32;
503 internal_irq_mask = __internal_irq_mask_32;
504 internal_irq_unmask = __internal_irq_unmask_32;
505 } else {
506 dispatch_internal = __dispatch_internal_64;
507 internal_irq_mask = __internal_irq_mask_64;
508 internal_irq_unmask = __internal_irq_unmask_64;
509 }
510}
511
512void __init arch_init_irq(void)
513{
514 int i, irq;
515
516 bcm63xx_init_irq();
517 mips_cpu_irq_init();
518 for (i = IRQ_INTERNAL_BASE; i < NR_IRQS; ++i)
519 irq_set_chip_and_handler(irq: i, chip: &bcm63xx_internal_irq_chip,
520 handle: handle_level_irq);
521
522 for (i = IRQ_EXTERNAL_BASE; i < IRQ_EXTERNAL_BASE + ext_irq_count; ++i)
523 irq_set_chip_and_handler(i, &bcm63xx_external_irq_chip,
524 handle_edge_irq);
525
526 if (!is_ext_irq_cascaded) {
527 for (i = 3; i < 3 + ext_irq_count; ++i) {
528 irq = MIPS_CPU_IRQ_BASE + i;
529 if (request_irq(irq, handler: no_action, IRQF_NO_THREAD,
530 name: "cascade_extirq", NULL)) {
531 pr_err("Failed to request irq %d (cascade_extirq)\n",
532 irq);
533 }
534 }
535 }
536
537 irq = MIPS_CPU_IRQ_BASE + 2;
538 if (request_irq(irq, handler: no_action, IRQF_NO_THREAD, name: "cascade_ip2", NULL))
539 pr_err("Failed to request irq %d (cascade_ip2)\n", irq);
540#ifdef CONFIG_SMP
541 if (is_ext_irq_cascaded) {
542 irq = MIPS_CPU_IRQ_BASE + 3;
543 if (request_irq(irq, handler: no_action, IRQF_NO_THREAD, name: "cascade_ip3",
544 NULL))
545 pr_err("Failed to request irq %d (cascade_ip3)\n", irq);
546 bcm63xx_internal_irq_chip.irq_set_affinity =
547 bcm63xx_internal_set_affinity;
548
549 cpumask_clear(dstp: irq_default_affinity);
550 cpumask_set_cpu(smp_processor_id(), dstp: irq_default_affinity);
551 }
552#endif
553}
554

source code of linux/arch/mips/bcm63xx/irq.c