]> git.proxmox.com Git - mirror_ubuntu-focal-kernel.git/blame - arch/blackfin/mach-common/smp.c
atomic: use <linux/atomic.h>
[mirror_ubuntu-focal-kernel.git] / arch / blackfin / mach-common / smp.c
CommitLineData
6b3087c6 1/*
96f1050d 2 * IPI management based on arch/arm/kernel/smp.c (Copyright 2002 ARM Limited)
6b3087c6 3 *
96f1050d
RG
4 * Copyright 2007-2009 Analog Devices Inc.
5 * Philippe Gerum <rpm@xenomai.org>
6b3087c6 6 *
96f1050d 7 * Licensed under the GPL-2.
6b3087c6
GY
8 */
9
10#include <linux/module.h>
11#include <linux/delay.h>
12#include <linux/init.h>
13#include <linux/spinlock.h>
14#include <linux/sched.h>
15#include <linux/interrupt.h>
16#include <linux/cache.h>
17#include <linux/profile.h>
18#include <linux/errno.h>
19#include <linux/mm.h>
20#include <linux/cpu.h>
21#include <linux/smp.h>
9c199b59 22#include <linux/cpumask.h>
6b3087c6
GY
23#include <linux/seq_file.h>
24#include <linux/irq.h>
5a0e3ad6 25#include <linux/slab.h>
60063497 26#include <linux/atomic.h>
6b3087c6 27#include <asm/cacheflush.h>
6327a574 28#include <asm/irq_handler.h>
6b3087c6
GY
29#include <asm/mmu_context.h>
30#include <asm/pgtable.h>
31#include <asm/pgalloc.h>
32#include <asm/processor.h>
33#include <asm/ptrace.h>
34#include <asm/cpu.h>
1fa9be72 35#include <asm/time.h>
6b3087c6
GY
36#include <linux/err.h>
37
555487bb
GY
38/*
39 * Anomaly notes:
40 * 05000120 - we always define corelock as 32-bit integer in L2
41 */
6b3087c6
GY
42struct corelock_slot corelock __attribute__ ((__section__(".l2.bss")));
43
c6345ab1
SZ
44#ifdef CONFIG_ICACHE_FLUSH_L1
45unsigned long blackfin_iflush_l1_entry[NR_CPUS];
46#endif
47
fb1d9be5 48struct blackfin_initial_pda __cpuinitdata initial_pda_coreb;
6b3087c6 49
6b3087c6
GY
50#define BFIN_IPI_RESCHEDULE 0
51#define BFIN_IPI_CALL_FUNC 1
52#define BFIN_IPI_CPU_STOP 2
53
54struct blackfin_flush_data {
55 unsigned long start;
56 unsigned long end;
57};
58
59void *secondary_stack;
60
61
62struct smp_call_struct {
63 void (*func)(void *info);
64 void *info;
65 int wait;
73a40064 66 cpumask_t *waitmask;
6b3087c6
GY
67};
68
69static struct blackfin_flush_data smp_flush_data;
70
71static DEFINE_SPINLOCK(stop_lock);
72
73struct ipi_message {
6b3087c6
GY
74 unsigned long type;
75 struct smp_call_struct call_struct;
76};
77
73a40064
YL
78/* A magic number - stress test shows this is safe for common cases */
79#define BFIN_IPI_MSGQ_LEN 5
80
81/* Simple FIFO buffer, overflow leads to panic */
6b3087c6 82struct ipi_message_queue {
6b3087c6
GY
83 spinlock_t lock;
84 unsigned long count;
73a40064
YL
85 unsigned long head; /* head of the queue */
86 struct ipi_message ipi_message[BFIN_IPI_MSGQ_LEN];
6b3087c6
GY
87};
88
89static DEFINE_PER_CPU(struct ipi_message_queue, ipi_msg_queue);
90
91static void ipi_cpu_stop(unsigned int cpu)
92{
93 spin_lock(&stop_lock);
94 printk(KERN_CRIT "CPU%u: stopping\n", cpu);
95 dump_stack();
96 spin_unlock(&stop_lock);
97
fecedc80 98 set_cpu_online(cpu, false);
6b3087c6
GY
99
100 local_irq_disable();
101
102 while (1)
103 SSYNC();
104}
105
106static void ipi_flush_icache(void *info)
107{
108 struct blackfin_flush_data *fdata = info;
109
110 /* Invalidate the memory holding the bounds of the flushed region. */
8d50de9e
SZ
111 blackfin_dcache_invalidate_range((unsigned long)fdata,
112 (unsigned long)fdata + sizeof(*fdata));
113
114 /* Make sure all write buffers in the data side of the core
115 * are flushed before trying to invalidate the icache. This
116 * needs to be after the data flush and before the icache
117 * flush so that the SSYNC does the right thing in preventing
118 * the instruction prefetcher from hitting things in cached
119 * memory at the wrong time -- it runs much further ahead than
120 * the pipeline.
121 */
122 SSYNC();
123
124 /* ipi_flaush_icache is invoked by generic flush_icache_range,
125 * so call blackfin arch icache flush directly here.
126 */
127 blackfin_icache_flush_range(fdata->start, fdata->end);
6b3087c6
GY
128}
129
130static void ipi_call_function(unsigned int cpu, struct ipi_message *msg)
131{
132 int wait;
133 void (*func)(void *info);
134 void *info;
135 func = msg->call_struct.func;
136 info = msg->call_struct.info;
137 wait = msg->call_struct.wait;
6b3087c6 138 func(info);
c9784ebb
YL
139 if (wait) {
140#ifdef __ARCH_SYNC_CORE_DCACHE
141 /*
142 * 'wait' usually means synchronization between CPUs.
143 * Invalidate D cache in case shared data was changed
144 * by func() to ensure cache coherence.
145 */
146 resync_core_dcache();
147#endif
fecedc80 148 cpumask_clear_cpu(cpu, msg->call_struct.waitmask);
73a40064 149 }
6b3087c6
GY
150}
151
73a40064
YL
152/* Use IRQ_SUPPLE_0 to request reschedule.
153 * When returning from interrupt to user space,
154 * there is chance to reschedule */
155static irqreturn_t ipi_handler_int0(int irq, void *dev_instance)
156{
157 unsigned int cpu = smp_processor_id();
158
159 platform_clear_ipi(cpu, IRQ_SUPPLE_0);
160 return IRQ_HANDLED;
161}
162
163static irqreturn_t ipi_handler_int1(int irq, void *dev_instance)
6b3087c6 164{
86f2008b 165 struct ipi_message *msg;
6b3087c6
GY
166 struct ipi_message_queue *msg_queue;
167 unsigned int cpu = smp_processor_id();
73a40064 168 unsigned long flags;
6b3087c6 169
73a40064 170 platform_clear_ipi(cpu, IRQ_SUPPLE_1);
6b3087c6
GY
171
172 msg_queue = &__get_cpu_var(ipi_msg_queue);
6b3087c6 173
73a40064
YL
174 spin_lock_irqsave(&msg_queue->lock, flags);
175
176 while (msg_queue->count) {
177 msg = &msg_queue->ipi_message[msg_queue->head];
6b3087c6 178 switch (msg->type) {
184748cc
PZ
179 case BFIN_IPI_RESCHEDULE:
180 scheduler_ipi();
181 break;
6b3087c6 182 case BFIN_IPI_CALL_FUNC:
73a40064 183 spin_unlock_irqrestore(&msg_queue->lock, flags);
6b3087c6 184 ipi_call_function(cpu, msg);
73a40064 185 spin_lock_irqsave(&msg_queue->lock, flags);
6b3087c6
GY
186 break;
187 case BFIN_IPI_CPU_STOP:
73a40064 188 spin_unlock_irqrestore(&msg_queue->lock, flags);
6b3087c6 189 ipi_cpu_stop(cpu);
73a40064 190 spin_lock_irqsave(&msg_queue->lock, flags);
6b3087c6
GY
191 break;
192 default:
db52ecc2
JP
193 printk(KERN_CRIT "CPU%u: Unknown IPI message 0x%lx\n",
194 cpu, msg->type);
6b3087c6
GY
195 break;
196 }
73a40064
YL
197 msg_queue->head++;
198 msg_queue->head %= BFIN_IPI_MSGQ_LEN;
199 msg_queue->count--;
6b3087c6 200 }
73a40064 201 spin_unlock_irqrestore(&msg_queue->lock, flags);
6b3087c6
GY
202 return IRQ_HANDLED;
203}
204
205static void ipi_queue_init(void)
206{
207 unsigned int cpu;
208 struct ipi_message_queue *msg_queue;
209 for_each_possible_cpu(cpu) {
210 msg_queue = &per_cpu(ipi_msg_queue, cpu);
6b3087c6
GY
211 spin_lock_init(&msg_queue->lock);
212 msg_queue->count = 0;
73a40064 213 msg_queue->head = 0;
6b3087c6
GY
214 }
215}
216
73a40064
YL
217static inline void smp_send_message(cpumask_t callmap, unsigned long type,
218 void (*func) (void *info), void *info, int wait)
6b3087c6
GY
219{
220 unsigned int cpu;
6b3087c6
GY
221 struct ipi_message_queue *msg_queue;
222 struct ipi_message *msg;
73a40064 223 unsigned long flags, next_msg;
fecedc80 224 cpumask_t waitmask; /* waitmask is shared by all cpus */
6b3087c6 225
fecedc80
KM
226 cpumask_copy(&waitmask, &callmap);
227 for_each_cpu(cpu, &callmap) {
6b3087c6
GY
228 msg_queue = &per_cpu(ipi_msg_queue, cpu);
229 spin_lock_irqsave(&msg_queue->lock, flags);
73a40064
YL
230 if (msg_queue->count < BFIN_IPI_MSGQ_LEN) {
231 next_msg = (msg_queue->head + msg_queue->count)
232 % BFIN_IPI_MSGQ_LEN;
233 msg = &msg_queue->ipi_message[next_msg];
234 msg->type = type;
235 if (type == BFIN_IPI_CALL_FUNC) {
236 msg->call_struct.func = func;
237 msg->call_struct.info = info;
238 msg->call_struct.wait = wait;
239 msg->call_struct.waitmask = &waitmask;
240 }
241 msg_queue->count++;
242 } else
243 panic("IPI message queue overflow\n");
6b3087c6 244 spin_unlock_irqrestore(&msg_queue->lock, flags);
73a40064 245 platform_send_ipi_cpu(cpu, IRQ_SUPPLE_1);
6b3087c6 246 }
73a40064 247
6b3087c6 248 if (wait) {
fecedc80 249 while (!cpumask_empty(&waitmask))
6b3087c6 250 blackfin_dcache_invalidate_range(
73a40064
YL
251 (unsigned long)(&waitmask),
252 (unsigned long)(&waitmask));
c9784ebb
YL
253#ifdef __ARCH_SYNC_CORE_DCACHE
254 /*
255 * Invalidate D cache in case shared data was changed by
256 * other processors to ensure cache coherence.
257 */
258 resync_core_dcache();
259#endif
6b3087c6 260 }
73a40064
YL
261}
262
263int smp_call_function(void (*func)(void *info), void *info, int wait)
264{
265 cpumask_t callmap;
266
567ebfc9 267 preempt_disable();
fecedc80
KM
268 cpumask_copy(&callmap, cpu_online_mask);
269 cpumask_clear_cpu(smp_processor_id(), &callmap);
270 if (!cpumask_empty(&callmap))
567ebfc9 271 smp_send_message(callmap, BFIN_IPI_CALL_FUNC, func, info, wait);
73a40064 272
567ebfc9 273 preempt_enable();
73a40064 274
6b3087c6
GY
275 return 0;
276}
277EXPORT_SYMBOL_GPL(smp_call_function);
278
279int smp_call_function_single(int cpuid, void (*func) (void *info), void *info,
280 int wait)
281{
282 unsigned int cpu = cpuid;
283 cpumask_t callmap;
6b3087c6
GY
284
285 if (cpu_is_offline(cpu))
286 return 0;
fecedc80
KM
287 cpumask_clear(&callmap);
288 cpumask_set_cpu(cpu, &callmap);
6b3087c6 289
73a40064 290 smp_send_message(callmap, BFIN_IPI_CALL_FUNC, func, info, wait);
6b3087c6 291
6b3087c6
GY
292 return 0;
293}
294EXPORT_SYMBOL_GPL(smp_call_function_single);
295
296void smp_send_reschedule(int cpu)
297{
73a40064 298 /* simply trigger an ipi */
6b3087c6
GY
299 if (cpu_is_offline(cpu))
300 return;
73a40064 301 platform_send_ipi_cpu(cpu, IRQ_SUPPLE_0);
6b3087c6
GY
302
303 return;
304}
305
306void smp_send_stop(void)
307{
6b3087c6 308 cpumask_t callmap;
6b3087c6 309
567ebfc9 310 preempt_disable();
fecedc80
KM
311 cpumask_copy(&callmap, cpu_online_mask);
312 cpumask_clear_cpu(smp_processor_id(), &callmap);
313 if (!cpumask_empty(&callmap))
567ebfc9 314 smp_send_message(callmap, BFIN_IPI_CPU_STOP, NULL, NULL, 0);
6b3087c6 315
567ebfc9 316 preempt_enable();
6b3087c6 317
6b3087c6
GY
318 return;
319}
320
321int __cpuinit __cpu_up(unsigned int cpu)
322{
6b3087c6 323 int ret;
0b39db28
GY
324 static struct task_struct *idle;
325
326 if (idle)
327 free_task(idle);
6b3087c6
GY
328
329 idle = fork_idle(cpu);
330 if (IS_ERR(idle)) {
331 printk(KERN_ERR "CPU%u: fork() failed\n", cpu);
332 return PTR_ERR(idle);
333 }
334
335 secondary_stack = task_stack_page(idle) + THREAD_SIZE;
6b3087c6
GY
336
337 ret = platform_boot_secondary(cpu, idle);
338
6b3087c6
GY
339 secondary_stack = NULL;
340
341 return ret;
342}
343
344static void __cpuinit setup_secondary(unsigned int cpu)
345{
6b3087c6
GY
346 unsigned long ilat;
347
348 bfin_write_IMASK(0);
349 CSYNC();
350 ilat = bfin_read_ILAT();
351 CSYNC();
352 bfin_write_ILAT(ilat);
353 CSYNC();
354
6b3087c6
GY
355 /* Enable interrupt levels IVG7-15. IARs have been already
356 * programmed by the boot CPU. */
40059784 357 bfin_irq_flags |= IMASK_IVG15 |
6b3087c6
GY
358 IMASK_IVG14 | IMASK_IVG13 | IMASK_IVG12 | IMASK_IVG11 |
359 IMASK_IVG10 | IMASK_IVG9 | IMASK_IVG8 | IMASK_IVG7 | IMASK_IVGHW;
6b3087c6
GY
360}
361
362void __cpuinit secondary_start_kernel(void)
363{
364 unsigned int cpu = smp_processor_id();
365 struct mm_struct *mm = &init_mm;
366
367 if (_bfin_swrst & SWRST_DBL_FAULT_B) {
368 printk(KERN_EMERG "CoreB Recovering from DOUBLE FAULT event\n");
369#ifdef CONFIG_DEBUG_DOUBLEFAULT
fb1d9be5
MF
370 printk(KERN_EMERG " While handling exception (EXCAUSE = %#x) at %pF\n",
371 initial_pda_coreb.seqstat_doublefault & SEQSTAT_EXCAUSE,
372 initial_pda_coreb.retx_doublefault);
373 printk(KERN_NOTICE " DCPLB_FAULT_ADDR: %pF\n",
374 initial_pda_coreb.dcplb_doublefault_addr);
375 printk(KERN_NOTICE " ICPLB_FAULT_ADDR: %pF\n",
376 initial_pda_coreb.icplb_doublefault_addr);
6b3087c6
GY
377#endif
378 printk(KERN_NOTICE " The instruction at %pF caused a double exception\n",
fb1d9be5 379 initial_pda_coreb.retx);
6b3087c6
GY
380 }
381
382 /*
383 * We want the D-cache to be enabled early, in case the atomic
384 * support code emulates cache coherence (see
385 * __ARCH_SYNC_CORE_DCACHE).
386 */
387 init_exception_vectors();
388
6b3087c6
GY
389 local_irq_disable();
390
391 /* Attach the new idle task to the global mm. */
392 atomic_inc(&mm->mm_users);
393 atomic_inc(&mm->mm_count);
394 current->active_mm = mm;
6b3087c6
GY
395
396 preempt_disable();
397
398 setup_secondary(cpu);
399
578d36f5
YL
400 platform_secondary_init(cpu);
401
0d152c27
YL
402 /* setup local core timer */
403 bfin_local_timer_setup();
404
6b3087c6
GY
405 local_irq_enable();
406
ab61d2ac 407 bfin_setup_caches(cpu);
408
578d36f5
YL
409 /*
410 * Calibrate loops per jiffy value.
411 * IRQs need to be enabled here - D-cache can be invalidated
412 * in timer irq handler, so core B can read correct jiffies.
413 */
414 calibrate_delay();
6b3087c6
GY
415
416 cpu_idle();
417}
418
419void __init smp_prepare_boot_cpu(void)
420{
421}
422
423void __init smp_prepare_cpus(unsigned int max_cpus)
424{
425 platform_prepare_cpus(max_cpus);
426 ipi_queue_init();
73a40064
YL
427 platform_request_ipi(IRQ_SUPPLE_0, ipi_handler_int0);
428 platform_request_ipi(IRQ_SUPPLE_1, ipi_handler_int1);
6b3087c6
GY
429}
430
431void __init smp_cpus_done(unsigned int max_cpus)
432{
433 unsigned long bogosum = 0;
434 unsigned int cpu;
435
436 for_each_online_cpu(cpu)
c70c754f 437 bogosum += loops_per_jiffy;
6b3087c6
GY
438
439 printk(KERN_INFO "SMP: Total of %d processors activated "
440 "(%lu.%02lu BogoMIPS).\n",
441 num_online_cpus(),
442 bogosum / (500000/HZ),
443 (bogosum / (5000/HZ)) % 100);
444}
445
446void smp_icache_flush_range_others(unsigned long start, unsigned long end)
447{
448 smp_flush_data.start = start;
449 smp_flush_data.end = end;
450
0bf3d933 451 if (smp_call_function(&ipi_flush_icache, &smp_flush_data, 0))
6b3087c6
GY
452 printk(KERN_WARNING "SMP: failed to run I-cache flush request on other CPUs\n");
453}
454EXPORT_SYMBOL_GPL(smp_icache_flush_range_others);
455
47e9dedb 456#ifdef __ARCH_SYNC_CORE_ICACHE
718340f6 457unsigned long icache_invld_count[NR_CPUS];
47e9dedb
SZ
458void resync_core_icache(void)
459{
460 unsigned int cpu = get_cpu();
461 blackfin_invalidate_entire_icache();
718340f6 462 icache_invld_count[cpu]++;
47e9dedb
SZ
463 put_cpu();
464}
465EXPORT_SYMBOL(resync_core_icache);
466#endif
467
6b3087c6 468#ifdef __ARCH_SYNC_CORE_DCACHE
718340f6 469unsigned long dcache_invld_count[NR_CPUS];
6b3087c6
GY
470unsigned long barrier_mask __attribute__ ((__section__(".l2.bss")));
471
472void resync_core_dcache(void)
473{
474 unsigned int cpu = get_cpu();
475 blackfin_invalidate_entire_dcache();
718340f6 476 dcache_invld_count[cpu]++;
6b3087c6
GY
477 put_cpu();
478}
479EXPORT_SYMBOL(resync_core_dcache);
480#endif
0b39db28
GY
481
482#ifdef CONFIG_HOTPLUG_CPU
483int __cpuexit __cpu_disable(void)
484{
485 unsigned int cpu = smp_processor_id();
486
487 if (cpu == 0)
488 return -EPERM;
489
490 set_cpu_online(cpu, false);
491 return 0;
492}
493
494static DECLARE_COMPLETION(cpu_killed);
495
496int __cpuexit __cpu_die(unsigned int cpu)
497{
498 return wait_for_completion_timeout(&cpu_killed, 5000);
499}
500
501void cpu_die(void)
502{
503 complete(&cpu_killed);
504
505 atomic_dec(&init_mm.mm_users);
506 atomic_dec(&init_mm.mm_count);
507
508 local_irq_disable();
509 platform_cpu_die();
510}
511#endif