summaryrefslogtreecommitdiff
path: root/arch/mips/kernel/smp.c
blob: 32c1e954cd3761d4c0f6c7625440387cf011f149 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
/*
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 *
 * Copyright (C) 2000, 2001 Kanoj Sarcar
 * Copyright (C) 2000, 2001 Ralf Baechle
 * Copyright (C) 2000, 2001 Silicon Graphics, Inc.
 * Copyright (C) 2000, 2001, 2003 Broadcom Corporation
 */
#include <linux/cache.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/smp.h>
#include <linux/spinlock.h>
#include <linux/threads.h>
#include <linux/module.h>
#include <linux/time.h>
#include <linux/timex.h>
#include <linux/sched.h>
#include <linux/cpumask.h>
#include <linux/cpu.h>
#include <linux/err.h>
#include <linux/ftrace.h>

#include <linux/atomic.h>
#include <asm/cpu.h>
#include <asm/processor.h>
#include <asm/r4k-timer.h>
#include <asm/system.h>
#include <asm/mmu_context.h>
#include <asm/time.h>

#ifdef CONFIG_MIPS_MT_SMTC
#include <asm/mipsmtregs.h>
#endif /* CONFIG_MIPS_MT_SMTC */

volatile cpumask_t cpu_callin_map;	/* Bitmask of started secondaries */

int __cpu_number_map[NR_CPUS];		/* Map physical to logical */
EXPORT_SYMBOL(__cpu_number_map);

int __cpu_logical_map[NR_CPUS];		/* Map logical to physical */
EXPORT_SYMBOL(__cpu_logical_map);

/* Number of TCs (or siblings in Intel speak) per CPU core */
int smp_num_siblings = 1;
EXPORT_SYMBOL(smp_num_siblings);

/* representing the TCs (or siblings in Intel speak) of each logical CPU */
cpumask_t cpu_sibling_map[NR_CPUS] __read_mostly;
EXPORT_SYMBOL(cpu_sibling_map);

/* representing cpus for which sibling maps can be computed */
static cpumask_t cpu_sibling_setup_map;

static inline void set_cpu_sibling_map(int cpu)
{
	int i;

	cpu_set(cpu, cpu_sibling_setup_map);

	if (smp_num_siblings > 1) {
		for_each_cpu_mask(i, cpu_sibling_setup_map) {
			if (cpu_data[cpu].core == cpu_data[i].core) {
				cpu_set(i, cpu_sibling_map[cpu]);
				cpu_set(cpu, cpu_sibling_map[i]);
			}
		}
	} else
		cpu_set(cpu, cpu_sibling_map[cpu]);
}

struct plat_smp_ops *mp_ops;

__cpuinit void register_smp_ops(struct plat_smp_ops *ops)
{
	if (mp_ops)
		printk(KERN_WARNING "Overriding previously set SMP ops\n");

	mp_ops = ops;
}

/*
 * First C code run on the secondary CPUs after being started up by
 * the master.
 */
asmlinkage __cpuinit void start_secondary(void)
{
	unsigned int cpu;

#ifdef CONFIG_MIPS_MT_SMTC
	/* Only do cpu_probe for first TC of CPU */
	if ((read_c0_tcbind() & TCBIND_CURTC) == 0)
#endif /* CONFIG_MIPS_MT_SMTC */
	cpu_probe();
	cpu_report();
	per_cpu_trap_init();
	mips_clockevent_init();
	mp_ops->init_secondary();

	/*
	 * XXX parity protection should be folded in here when it's converted
	 * to an option instead of something based on .cputype
	 */

	calibrate_delay();
	preempt_disable();
	cpu = smp_processor_id();
	cpu_data[cpu].udelay_val = loops_per_jiffy;

	notify_cpu_starting(cpu);

	mp_ops->smp_finish();
	set_cpu_sibling_map(cpu);

	cpu_set(cpu, cpu_callin_map);

	synchronise_count_slave();

	cpu_idle();
}

/*
 * Call into both interrupt handlers, as we share the IPI for them
 */
void __irq_entry smp_call_function_interrupt(void)
{
	irq_enter();
	generic_smp_call_function_single_interrupt();
	generic_smp_call_function_interrupt();
	irq_exit();
}

static void stop_this_cpu(void *dummy)
{
	/*
	 * Remove this CPU:
	 */
	cpu_clear(smp_processor_id(), cpu_online_map);
	for (;;) {
		if (cpu_wait)
			(*cpu_wait)();		/* Wait if available. */
	}
}

void smp_send_stop(void)
{
	smp_call_function(stop_this_cpu, NULL, 0);
}

void __init smp_cpus_done(unsigned int max_cpus)
{
	mp_ops->cpus_done();
	synchronise_count_master();
}

/* called from main before smp_init() */
void __init smp_prepare_cpus(unsigned int max_cpus)
{
	init_new_context(current, &init_mm);
	current_thread_info()->cpu = 0;
	mp_ops->prepare_cpus(max_cpus);
	set_cpu_sibling_map(0);
#ifndef CONFIG_HOTPLUG_CPU
	init_cpu_present(&cpu_possible_map);
#endif
}

/* preload SMP state for boot cpu */
void __devinit smp_prepare_boot_cpu(void)
{
	set_cpu_possible(0, true);
	set_cpu_online(0, true);
	cpu_set(0, cpu_callin_map);
}

/*
 * Called once for each "cpu_possible(cpu)".  Needs to spin up the cpu
 * and keep control until "cpu_online(cpu)" is set.  Note: cpu is
 * physical, not logical.
 */
static struct task_struct *cpu_idle_thread[NR_CPUS];

struct create_idle {
	struct work_struct work;
	struct task_struct *idle;
	struct completion done;
	int cpu;
};

static void __cpuinit do_fork_idle(struct work_struct *work)
{
	struct create_idle *c_idle =
		container_of(work, struct create_idle, work);

	c_idle->idle = fork_idle(c_idle->cpu);
	complete(&c_idle->done);
}

int __cpuinit __cpu_up(unsigned int cpu)
{
	struct task_struct *idle;

	/*
	 * Processor goes to start_secondary(), sets online flag
	 * The following code is purely to make sure
	 * Linux can schedule processes on this slave.
	 */
	if (!cpu_idle_thread[cpu]) {
		/*
		 * Schedule work item to avoid forking user task
		 * Ported from arch/x86/kernel/smpboot.c
		 */
		struct create_idle c_idle = {
			.cpu    = cpu,
			.done   = COMPLETION_INITIALIZER_ONSTACK(c_idle.done),
		};

		INIT_WORK_ONSTACK(&c_idle.work, do_fork_idle);
		schedule_work(&c_idle.work);
		wait_for_completion(&c_idle.done);
		idle = cpu_idle_thread[cpu] = c_idle.idle;

		if (IS_ERR(idle))
			panic(KERN_ERR "Fork failed for CPU %d", cpu);
	} else {
		idle = cpu_idle_thread[cpu];
		init_idle(idle, cpu);
	}

	mp_ops->boot_secondary(cpu, idle);

	/*
	 * Trust is futile.  We should really have timeouts ...
	 */
	while (!cpu_isset(cpu, cpu_callin_map))
		udelay(100);

	cpu_set(cpu, cpu_online_map);

	return 0;
}

/* Not really SMP stuff ... */
int setup_profiling_timer(unsigned int multiplier)
{
	return 0;
}

static void flush_tlb_all_ipi(void *info)
{
	local_flush_tlb_all();
}

void flush_tlb_all(void)
{
	on_each_cpu(flush_tlb_all_ipi, NULL, 1);
}

static void flush_tlb_mm_ipi(void *mm)
{
	local_flush_tlb_mm((struct mm_struct *)mm);
}

/*
 * Special Variant of smp_call_function for use by TLB functions:
 *
 *  o No return value
 *  o collapses to normal function call on UP kernels
 *  o collapses to normal function call on systems with a single shared
 *    primary cache.
 *  o CONFIG_MIPS_MT_SMTC currently implies there is only one physical core.
 */
static inline void smp_on_other_tlbs(void (*func) (void *info), void *info)
{
#ifndef CONFIG_MIPS_MT_SMTC
	smp_call_function(func, info, 1);
#endif
}

static inline void smp_on_each_tlb(void (*func) (void *info), void *info)
{
	preempt_disable();

	smp_on_other_tlbs(func, info);
	func(info);

	preempt_enable();
}

/*
 * The following tlb flush calls are invoked when old translations are
 * being torn down, or pte attributes are changing. For single threaded
 * address spaces, a new context is obtained on the current cpu, and tlb
 * context on other cpus are invalidated to force a new context allocation
 * at switch_mm time, should the mm ever be used on other cpus. For
 * multithreaded address spaces, intercpu interrupts have to be sent.
 * Another case where intercpu interrupts are required is when the target
 * mm might be active on another cpu (eg debuggers doing the flushes on
 * behalf of debugees, kswapd stealing pages from another process etc).
 * Kanoj 07/00.
 */

void flush_tlb_mm(struct mm_struct *mm)
{
	preempt_disable();

	if ((atomic_read(&mm->mm_users) != 1) || (current->mm != mm)) {
		smp_on_other_tlbs(flush_tlb_mm_ipi, mm);
	} else {
		cpumask_t mask = cpu_online_map;
		unsigned int cpu;

		cpu_clear(smp_processor_id(), mask);
		for_each_cpu_mask(cpu, mask)
			if (cpu_context(cpu, mm))
				cpu_context(cpu, mm) = 0;
	}
	local_flush_tlb_mm(mm);

	preempt_enable();
}

struct flush_tlb_data {
	struct vm_area_struct *vma;
	unsigned long addr1;
	unsigned long addr2;
};

static void flush_tlb_range_ipi(void *info)
{
	struct flush_tlb_data *fd = info;

	local_flush_tlb_range(fd->vma, fd->addr1, fd->addr2);
}

void flush_tlb_range(struct vm_area_struct *vma, unsigned long start, unsigned long end)
{
	struct mm_struct *mm = vma->vm_mm;

	preempt_disable();
	if ((atomic_read(&mm->mm_users) != 1) || (current->mm != mm)) {
		struct flush_tlb_data fd = {
			.vma = vma,
			.addr1 = start,
			.addr2 = end,
		};

		smp_on_other_tlbs(flush_tlb_range_ipi, &fd);
	} else {
		cpumask_t mask = cpu_online_map;
		unsigned int cpu;

		cpu_clear(smp_processor_id(), mask);
		for_each_cpu_mask(cpu, mask)
			if (cpu_context(cpu, mm))
				cpu_context(cpu, mm) = 0;
	}
	local_flush_tlb_range(vma, start, end);
	preempt_enable();
}

static void flush_tlb_kernel_range_ipi(void *info)
{
	struct flush_tlb_data *fd = info;

	local_flush_tlb_kernel_range(fd->addr1, fd->addr2);
}

void flush_tlb_kernel_range(unsigned long start, unsigned long end)
{
	struct flush_tlb_data fd = {
		.addr1 = start,
		.addr2 = end,
	};

	on_each_cpu(flush_tlb_kernel_range_ipi, &fd, 1);
}

static void flush_tlb_page_ipi(void *info)
{
	struct flush_tlb_data *fd = info;

	local_flush_tlb_page(fd->vma, fd->addr1);
}

void flush_tlb_page(struct vm_area_struct *vma, unsigned long page)
{
	preempt_disable();
	if ((atomic_read(&vma->vm_mm->mm_users) != 1) || (current->mm != vma->vm_mm)) {
		struct flush_tlb_data fd = {
			.vma = vma,
			.addr1 = page,
		};

		smp_on_other_tlbs(flush_tlb_page_ipi, &fd);
	} else {
		cpumask_t mask = cpu_online_map;
		unsigned int cpu;

		cpu_clear(smp_processor_id(), mask);
		for_each_cpu_mask(cpu, mask)
			if (cpu_context(cpu, vma->vm_mm))
				cpu_context(cpu, vma->vm_mm) = 0;
	}
	local_flush_tlb_page(vma, page);
	preempt_enable();
}

static void flush_tlb_one_ipi(void *info)
{
	unsigned long vaddr = (unsigned long) info;

	local_flush_tlb_one(vaddr);
}

void flush_tlb_one(unsigned long vaddr)
{
	smp_on_each_tlb(flush_tlb_one_ipi, (void *) vaddr);
}

EXPORT_SYMBOL(flush_tlb_page);
EXPORT_SYMBOL(flush_tlb_one);