1 /*
2 * SS1000/SC2000 interrupt handling.
3 *
4 * Copyright (C) 1997,1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
5 * Heavily based on arch/sparc/kernel/irq.c.
6 */
7
8 #include <linux/kernel_stat.h>
9 #include <linux/seq_file.h>
10
11 #include <asm/timer.h>
12 #include <asm/traps.h>
13 #include <asm/irq.h>
14 #include <asm/io.h>
15 #include <asm/sbi.h>
16 #include <asm/cacheflush.h>
17 #include <asm/setup.h>
18
19 #include "kernel.h"
20 #include "irq.h"
21
22 /* Sun4d interrupts fall roughly into two categories. SBUS and
23 * cpu local. CPU local interrupts cover the timer interrupts
24 * and whatnot, and we encode those as normal PILs between
25 * 0 and 15.
26 * SBUS interrupts are encodes as a combination of board, level and slot.
27 */
28
29 struct sun4d_handler_data {
30 unsigned int cpuid; /* target cpu */
31 unsigned int real_irq; /* interrupt level */
32 };
33
34
sun4d_encode_irq(int board,int lvl,int slot)35 static unsigned int sun4d_encode_irq(int board, int lvl, int slot)
36 {
37 return (board + 1) << 5 | (lvl << 2) | slot;
38 }
39
40 struct sun4d_timer_regs {
41 u32 l10_timer_limit;
42 u32 l10_cur_countx;
43 u32 l10_limit_noclear;
44 u32 ctrl;
45 u32 l10_cur_count;
46 };
47
48 static struct sun4d_timer_regs __iomem *sun4d_timers;
49
50 #define SUN4D_TIMER_IRQ 10
51
52 /* Specify which cpu handle interrupts from which board.
53 * Index is board - value is cpu.
54 */
55 static unsigned char board_to_cpu[32];
56
57 static int pil_to_sbus[] = {
58 0,
59 0,
60 1,
61 2,
62 0,
63 3,
64 0,
65 4,
66 0,
67 5,
68 0,
69 6,
70 0,
71 7,
72 0,
73 0,
74 };
75
76 /* Exported for sun4d_smp.c */
77 DEFINE_SPINLOCK(sun4d_imsk_lock);
78
79 /* SBUS interrupts are encoded integers including the board number
80 * (plus one), the SBUS level, and the SBUS slot number. Sun4D
81 * IRQ dispatch is done by:
82 *
83 * 1) Reading the BW local interrupt table in order to get the bus
84 * interrupt mask.
85 *
86 * This table is indexed by SBUS interrupt level which can be
87 * derived from the PIL we got interrupted on.
88 *
89 * 2) For each bus showing interrupt pending from #1, read the
90 * SBI interrupt state register. This will indicate which slots
91 * have interrupts pending for that SBUS interrupt level.
92 *
93 * 3) Call the genreric IRQ support.
94 */
sun4d_sbus_handler_irq(int sbusl)95 static void sun4d_sbus_handler_irq(int sbusl)
96 {
97 unsigned int bus_mask;
98 unsigned int sbino, slot;
99 unsigned int sbil;
100
101 bus_mask = bw_get_intr_mask(sbusl) & 0x3ffff;
102 bw_clear_intr_mask(sbusl, bus_mask);
103
104 sbil = (sbusl << 2);
105 /* Loop for each pending SBI */
106 for (sbino = 0; bus_mask; sbino++, bus_mask >>= 1) {
107 unsigned int idx, mask;
108
109 if (!(bus_mask & 1))
110 continue;
111 /* XXX This seems to ACK the irq twice. acquire_sbi()
112 * XXX uses swap, therefore this writes 0xf << sbil,
113 * XXX then later release_sbi() will write the individual
114 * XXX bits which were set again.
115 */
116 mask = acquire_sbi(SBI2DEVID(sbino), 0xf << sbil);
117 mask &= (0xf << sbil);
118
119 /* Loop for each pending SBI slot */
120 slot = (1 << sbil);
121 for (idx = 0; mask != 0; idx++, slot <<= 1) {
122 unsigned int pil;
123 struct irq_bucket *p;
124
125 if (!(mask & slot))
126 continue;
127
128 mask &= ~slot;
129 pil = sun4d_encode_irq(sbino, sbusl, idx);
130
131 p = irq_map[pil];
132 while (p) {
133 struct irq_bucket *next;
134
135 next = p->next;
136 generic_handle_irq(p->irq);
137 p = next;
138 }
139 release_sbi(SBI2DEVID(sbino), slot);
140 }
141 }
142 }
143
sun4d_handler_irq(int pil,struct pt_regs * regs)144 void sun4d_handler_irq(int pil, struct pt_regs *regs)
145 {
146 struct pt_regs *old_regs;
147 /* SBUS IRQ level (1 - 7) */
148 int sbusl = pil_to_sbus[pil];
149
150 /* FIXME: Is this necessary?? */
151 cc_get_ipen();
152
153 cc_set_iclr(1 << pil);
154
155 #ifdef CONFIG_SMP
156 /*
157 * Check IPI data structures after IRQ has been cleared. Hard and Soft
158 * IRQ can happen at the same time, so both cases are always handled.
159 */
160 if (pil == SUN4D_IPI_IRQ)
161 sun4d_ipi_interrupt();
162 #endif
163
164 old_regs = set_irq_regs(regs);
165 irq_enter();
166 if (sbusl == 0) {
167 /* cpu interrupt */
168 struct irq_bucket *p;
169
170 p = irq_map[pil];
171 while (p) {
172 struct irq_bucket *next;
173
174 next = p->next;
175 generic_handle_irq(p->irq);
176 p = next;
177 }
178 } else {
179 /* SBUS interrupt */
180 sun4d_sbus_handler_irq(sbusl);
181 }
182 irq_exit();
183 set_irq_regs(old_regs);
184 }
185
186
sun4d_mask_irq(struct irq_data * data)187 static void sun4d_mask_irq(struct irq_data *data)
188 {
189 struct sun4d_handler_data *handler_data = data->handler_data;
190 unsigned int real_irq;
191 #ifdef CONFIG_SMP
192 int cpuid = handler_data->cpuid;
193 unsigned long flags;
194 #endif
195 real_irq = handler_data->real_irq;
196 #ifdef CONFIG_SMP
197 spin_lock_irqsave(&sun4d_imsk_lock, flags);
198 cc_set_imsk_other(cpuid, cc_get_imsk_other(cpuid) | (1 << real_irq));
199 spin_unlock_irqrestore(&sun4d_imsk_lock, flags);
200 #else
201 cc_set_imsk(cc_get_imsk() | (1 << real_irq));
202 #endif
203 }
204
sun4d_unmask_irq(struct irq_data * data)205 static void sun4d_unmask_irq(struct irq_data *data)
206 {
207 struct sun4d_handler_data *handler_data = data->handler_data;
208 unsigned int real_irq;
209 #ifdef CONFIG_SMP
210 int cpuid = handler_data->cpuid;
211 unsigned long flags;
212 #endif
213 real_irq = handler_data->real_irq;
214
215 #ifdef CONFIG_SMP
216 spin_lock_irqsave(&sun4d_imsk_lock, flags);
217 cc_set_imsk_other(cpuid, cc_get_imsk_other(cpuid) & ~(1 << real_irq));
218 spin_unlock_irqrestore(&sun4d_imsk_lock, flags);
219 #else
220 cc_set_imsk(cc_get_imsk() & ~(1 << real_irq));
221 #endif
222 }
223
sun4d_startup_irq(struct irq_data * data)224 static unsigned int sun4d_startup_irq(struct irq_data *data)
225 {
226 irq_link(data->irq);
227 sun4d_unmask_irq(data);
228 return 0;
229 }
230
sun4d_shutdown_irq(struct irq_data * data)231 static void sun4d_shutdown_irq(struct irq_data *data)
232 {
233 sun4d_mask_irq(data);
234 irq_unlink(data->irq);
235 }
236
237 struct irq_chip sun4d_irq = {
238 .name = "sun4d",
239 .irq_startup = sun4d_startup_irq,
240 .irq_shutdown = sun4d_shutdown_irq,
241 .irq_unmask = sun4d_unmask_irq,
242 .irq_mask = sun4d_mask_irq,
243 };
244
245 #ifdef CONFIG_SMP
sun4d_set_cpu_int(int cpu,int level)246 static void sun4d_set_cpu_int(int cpu, int level)
247 {
248 sun4d_send_ipi(cpu, level);
249 }
250
sun4d_clear_ipi(int cpu,int level)251 static void sun4d_clear_ipi(int cpu, int level)
252 {
253 }
254
sun4d_set_udt(int cpu)255 static void sun4d_set_udt(int cpu)
256 {
257 }
258
259 /* Setup IRQ distribution scheme. */
sun4d_distribute_irqs(void)260 void __init sun4d_distribute_irqs(void)
261 {
262 struct device_node *dp;
263
264 int cpuid = cpu_logical_map(1);
265
266 if (cpuid == -1)
267 cpuid = cpu_logical_map(0);
268 for_each_node_by_name(dp, "sbi") {
269 int devid = of_getintprop_default(dp, "device-id", 0);
270 int board = of_getintprop_default(dp, "board#", 0);
271 board_to_cpu[board] = cpuid;
272 set_sbi_tid(devid, cpuid << 3);
273 }
274 printk(KERN_ERR "All sbus IRQs directed to CPU%d\n", cpuid);
275 }
276 #endif
277
sun4d_clear_clock_irq(void)278 static void sun4d_clear_clock_irq(void)
279 {
280 sbus_readl(&sun4d_timers->l10_timer_limit);
281 }
282
sun4d_load_profile_irq(int cpu,unsigned int limit)283 static void sun4d_load_profile_irq(int cpu, unsigned int limit)
284 {
285 bw_set_prof_limit(cpu, limit);
286 }
287
sun4d_load_profile_irqs(void)288 static void __init sun4d_load_profile_irqs(void)
289 {
290 int cpu = 0, mid;
291
292 while (!cpu_find_by_instance(cpu, NULL, &mid)) {
293 sun4d_load_profile_irq(mid >> 3, 0);
294 cpu++;
295 }
296 }
297
_sun4d_build_device_irq(unsigned int real_irq,unsigned int pil,unsigned int board)298 unsigned int _sun4d_build_device_irq(unsigned int real_irq,
299 unsigned int pil,
300 unsigned int board)
301 {
302 struct sun4d_handler_data *handler_data;
303 unsigned int irq;
304
305 irq = irq_alloc(real_irq, pil);
306 if (irq == 0) {
307 prom_printf("IRQ: allocate for %d %d %d failed\n",
308 real_irq, pil, board);
309 goto err_out;
310 }
311
312 handler_data = irq_get_handler_data(irq);
313 if (unlikely(handler_data))
314 goto err_out;
315
316 handler_data = kzalloc(sizeof(struct sun4d_handler_data), GFP_ATOMIC);
317 if (unlikely(!handler_data)) {
318 prom_printf("IRQ: kzalloc(sun4d_handler_data) failed.\n");
319 prom_halt();
320 }
321 handler_data->cpuid = board_to_cpu[board];
322 handler_data->real_irq = real_irq;
323 irq_set_chip_and_handler_name(irq, &sun4d_irq,
324 handle_level_irq, "level");
325 irq_set_handler_data(irq, handler_data);
326
327 err_out:
328 return irq;
329 }
330
331
332
sun4d_build_device_irq(struct platform_device * op,unsigned int real_irq)333 unsigned int sun4d_build_device_irq(struct platform_device *op,
334 unsigned int real_irq)
335 {
336 struct device_node *dp = op->dev.of_node;
337 struct device_node *board_parent, *bus = dp->parent;
338 char *bus_connection;
339 const struct linux_prom_registers *regs;
340 unsigned int pil;
341 unsigned int irq;
342 int board, slot;
343 int sbusl;
344
345 irq = real_irq;
346 while (bus) {
347 if (!strcmp(bus->name, "sbi")) {
348 bus_connection = "io-unit";
349 break;
350 }
351
352 if (!strcmp(bus->name, "bootbus")) {
353 bus_connection = "cpu-unit";
354 break;
355 }
356
357 bus = bus->parent;
358 }
359 if (!bus)
360 goto err_out;
361
362 regs = of_get_property(dp, "reg", NULL);
363 if (!regs)
364 goto err_out;
365
366 slot = regs->which_io;
367
368 /*
369 * If Bus nodes parent is not io-unit/cpu-unit or the io-unit/cpu-unit
370 * lacks a "board#" property, something is very wrong.
371 */
372 if (!bus->parent || strcmp(bus->parent->name, bus_connection)) {
373 printk(KERN_ERR "%s: Error, parent is not %s.\n",
374 bus->full_name, bus_connection);
375 goto err_out;
376 }
377 board_parent = bus->parent;
378 board = of_getintprop_default(board_parent, "board#", -1);
379 if (board == -1) {
380 printk(KERN_ERR "%s: Error, lacks board# property.\n",
381 board_parent->full_name);
382 goto err_out;
383 }
384
385 sbusl = pil_to_sbus[real_irq];
386 if (sbusl)
387 pil = sun4d_encode_irq(board, sbusl, slot);
388 else
389 pil = real_irq;
390
391 irq = _sun4d_build_device_irq(real_irq, pil, board);
392 err_out:
393 return irq;
394 }
395
sun4d_build_timer_irq(unsigned int board,unsigned int real_irq)396 unsigned int sun4d_build_timer_irq(unsigned int board, unsigned int real_irq)
397 {
398 return _sun4d_build_device_irq(real_irq, real_irq, board);
399 }
400
401
sun4d_fixup_trap_table(void)402 static void __init sun4d_fixup_trap_table(void)
403 {
404 #ifdef CONFIG_SMP
405 unsigned long flags;
406 struct tt_entry *trap_table = &sparc_ttable[SP_TRAP_IRQ1 + (14 - 1)];
407
408 /* Adjust so that we jump directly to smp4d_ticker */
409 lvl14_save[2] += smp4d_ticker - real_irq_entry;
410
411 /* For SMP we use the level 14 ticker, however the bootup code
412 * has copied the firmware's level 14 vector into the boot cpu's
413 * trap table, we must fix this now or we get squashed.
414 */
415 local_irq_save(flags);
416 patchme_maybe_smp_msg[0] = 0x01000000; /* NOP out the branch */
417 trap_table->inst_one = lvl14_save[0];
418 trap_table->inst_two = lvl14_save[1];
419 trap_table->inst_three = lvl14_save[2];
420 trap_table->inst_four = lvl14_save[3];
421 local_flush_cache_all();
422 local_irq_restore(flags);
423 #endif
424 }
425
sun4d_init_timers(irq_handler_t counter_fn)426 static void __init sun4d_init_timers(irq_handler_t counter_fn)
427 {
428 struct device_node *dp;
429 struct resource res;
430 unsigned int irq;
431 const u32 *reg;
432 int err;
433 int board;
434
435 dp = of_find_node_by_name(NULL, "cpu-unit");
436 if (!dp) {
437 prom_printf("sun4d_init_timers: Unable to find cpu-unit\n");
438 prom_halt();
439 }
440
441 /* Which cpu-unit we use is arbitrary, we can view the bootbus timer
442 * registers via any cpu's mapping. The first 'reg' property is the
443 * bootbus.
444 */
445 reg = of_get_property(dp, "reg", NULL);
446 if (!reg) {
447 prom_printf("sun4d_init_timers: No reg property\n");
448 prom_halt();
449 }
450
451 board = of_getintprop_default(dp, "board#", -1);
452 if (board == -1) {
453 prom_printf("sun4d_init_timers: No board# property on cpu-unit\n");
454 prom_halt();
455 }
456
457 of_node_put(dp);
458
459 res.start = reg[1];
460 res.end = reg[2] - 1;
461 res.flags = reg[0] & 0xff;
462 sun4d_timers = of_ioremap(&res, BW_TIMER_LIMIT,
463 sizeof(struct sun4d_timer_regs), "user timer");
464 if (!sun4d_timers) {
465 prom_printf("sun4d_init_timers: Can't map timer regs\n");
466 prom_halt();
467 }
468
469 sbus_writel((((1000000/HZ) + 1) << 10), &sun4d_timers->l10_timer_limit);
470
471 master_l10_counter = &sun4d_timers->l10_cur_count;
472
473 irq = sun4d_build_timer_irq(board, SUN4D_TIMER_IRQ);
474 err = request_irq(irq, counter_fn, IRQF_TIMER, "timer", NULL);
475 if (err) {
476 prom_printf("sun4d_init_timers: request_irq() failed with %d\n",
477 err);
478 prom_halt();
479 }
480 sun4d_load_profile_irqs();
481 sun4d_fixup_trap_table();
482 }
483
sun4d_init_sbi_irq(void)484 void __init sun4d_init_sbi_irq(void)
485 {
486 struct device_node *dp;
487 int target_cpu;
488
489 target_cpu = boot_cpu_id;
490 for_each_node_by_name(dp, "sbi") {
491 int devid = of_getintprop_default(dp, "device-id", 0);
492 int board = of_getintprop_default(dp, "board#", 0);
493 unsigned int mask;
494
495 set_sbi_tid(devid, target_cpu << 3);
496 board_to_cpu[board] = target_cpu;
497
498 /* Get rid of pending irqs from PROM */
499 mask = acquire_sbi(devid, 0xffffffff);
500 if (mask) {
501 printk(KERN_ERR "Clearing pending IRQs %08x on SBI %d\n",
502 mask, board);
503 release_sbi(devid, mask);
504 }
505 }
506 }
507
sun4d_init_IRQ(void)508 void __init sun4d_init_IRQ(void)
509 {
510 local_irq_disable();
511
512 BTFIXUPSET_CALL(clear_clock_irq, sun4d_clear_clock_irq, BTFIXUPCALL_NORM);
513 BTFIXUPSET_CALL(load_profile_irq, sun4d_load_profile_irq, BTFIXUPCALL_NORM);
514
515 sparc_irq_config.init_timers = sun4d_init_timers;
516 sparc_irq_config.build_device_irq = sun4d_build_device_irq;
517
518 #ifdef CONFIG_SMP
519 BTFIXUPSET_CALL(set_cpu_int, sun4d_set_cpu_int, BTFIXUPCALL_NORM);
520 BTFIXUPSET_CALL(clear_cpu_int, sun4d_clear_ipi, BTFIXUPCALL_NOP);
521 BTFIXUPSET_CALL(set_irq_udt, sun4d_set_udt, BTFIXUPCALL_NOP);
522 #endif
523 /* Cannot enable interrupts until OBP ticker is disabled. */
524 }
525