summaryrefslogtreecommitdiffstats
path: root/arch/sparc/kernel/sun4m_smp.c
blob: 4e07bdbbfb5d233324b54fd12ed21eed2fa4e77c (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
/* sun4m_smp.c: Sparc SUN4M SMP support.
 *
 * Copyright (C) 1996 David S. Miller (davem@caip.rutgers.edu)
 */

#include <asm/head.h>

#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/threads.h>
#include <linux/smp.h>
#include <linux/smp_lock.h>
#include <linux/interrupt.h>
#include <linux/kernel_stat.h>
#include <linux/init.h>
#include <linux/spinlock.h>
#include <linux/mm.h>
#include <linux/swap.h>
#include <linux/profile.h>
#include <asm/cacheflush.h>
#include <asm/tlbflush.h>
#include <asm/irq_regs.h>

#include <asm/ptrace.h>
#include <asm/atomic.h>

#include <asm/delay.h>
#include <asm/irq.h>
#include <asm/page.h>
#include <asm/pgalloc.h>
#include <asm/pgtable.h>
#include <asm/oplib.h>
#include <asm/cpudata.h>

#define IRQ_RESCHEDULE		13
#define IRQ_STOP_CPU		14
#define IRQ_CROSS_CALL		15

extern ctxd_t *srmmu_ctx_table_phys;

extern void calibrate_delay(void);

extern volatile unsigned long cpu_callin_map[NR_CPUS];
extern unsigned char boot_cpu_id;

extern cpumask_t smp_commenced_mask;

extern int __smp4m_processor_id(void);

/*#define SMP_DEBUG*/

#ifdef SMP_DEBUG
#define SMP_PRINTK(x)	printk x
#else
#define SMP_PRINTK(x)
#endif

static inline unsigned long swap(volatile unsigned long *ptr, unsigned long val)
{
	__asm__ __volatile__("swap [%1], %0\n\t" :
			     "=&r" (val), "=&r" (ptr) :
			     "0" (val), "1" (ptr));
	return val;
}

static void smp_setup_percpu_timer(void);
extern void cpu_probe(void);

void __cpuinit smp4m_callin(void)
{
	int cpuid = hard_smp_processor_id();

	local_flush_cache_all();
	local_flush_tlb_all();

	/* Get our local ticker going. */
	smp_setup_percpu_timer();

	calibrate_delay();
	smp_store_cpu_info(cpuid);

	local_flush_cache_all();
	local_flush_tlb_all();

	/*
	 * Unblock the master CPU _only_ when the scheduler state
	 * of all secondary CPUs will be up-to-date, so after
	 * the SMP initialization the master will be just allowed
	 * to call the scheduler code.
	 */
	/* Allow master to continue. */
	swap(&cpu_callin_map[cpuid], 1);

	/* XXX: What's up with all the flushes? */
	local_flush_cache_all();
	local_flush_tlb_all();
	
	cpu_probe();

	/* Fix idle thread fields. */
	__asm__ __volatile__("ld [%0], %%g6\n\t"
			     : : "r" (&current_set[cpuid])
			     : "memory" /* paranoid */);

	/* Attach to the address space of init_task. */
	atomic_inc(&init_mm.mm_count);
	current->active_mm = &init_mm;

	while (!cpu_isset(cpuid, smp_commenced_mask))
		mb();

	local_irq_enable();

	cpu_set(cpuid, cpu_online_map);
}

/*
 *	Cycle through the processors asking the PROM to start each one.
 */
 
extern struct linux_prom_registers smp_penguin_ctable;
extern unsigned long trapbase_cpu1[];
extern unsigned long trapbase_cpu2[];
extern unsigned long trapbase_cpu3[];

void __init smp4m_boot_cpus(void)
{
	smp_setup_percpu_timer();
	local_flush_cache_all();
}

int __cpuinit smp4m_boot_one_cpu(int i)
{
	extern unsigned long sun4m_cpu_startup;
	unsigned long *entry = &sun4m_cpu_startup;
	struct task_struct *p;
	int timeout;
	int cpu_node;

	cpu_find_by_mid(i, &cpu_node);

	/* Cook up an idler for this guy. */
	p = fork_idle(i);
	current_set[i] = task_thread_info(p);
	/* See trampoline.S for details... */
	entry += ((i-1) * 3);

	/*
	 * Initialize the contexts table
	 * Since the call to prom_startcpu() trashes the structure,
	 * we need to re-initialize it for each cpu
	 */
	smp_penguin_ctable.which_io = 0;
	smp_penguin_ctable.phys_addr = (unsigned int) srmmu_ctx_table_phys;
	smp_penguin_ctable.reg_size = 0;

	/* whirrr, whirrr, whirrrrrrrrr... */
	printk("Starting CPU %d at %p\n", i, entry);
	local_flush_cache_all();
	prom_startcpu(cpu_node,
		      &smp_penguin_ctable, 0, (char *)entry);

	/* wheee... it's going... */
	for(timeout = 0; timeout < 10000; timeout++) {
		if(cpu_callin_map[i])
			break;
		udelay(200);
	}

	if (!(cpu_callin_map[i])) {
		printk("Processor %d is stuck.\n", i);
		return -ENODEV;
	}

	local_flush_cache_all();
	return 0;
}

void __init smp4m_smp_done(void)
{
	int i, first;
	int *prev;

	/* setup cpu list for irq rotation */
	first = 0;
	prev = &first;
	for (i = 0; i < NR_CPUS; i++) {
		if (cpu_online(i)) {
			*prev = i;
			prev = &cpu_data(i).next;
		}
	}
	*prev = first;
	local_flush_cache_all();

	/* Free unneeded trap tables */
	if (!cpu_isset(1, cpu_present_map)) {
		ClearPageReserved(virt_to_page(trapbase_cpu1));
		init_page_count(virt_to_page(trapbase_cpu1));
		free_page((unsigned long)trapbase_cpu1);
		totalram_pages++;
		num_physpages++;
	}
	if (!cpu_isset(2, cpu_present_map)) {
		ClearPageReserved(virt_to_page(trapbase_cpu2));
		init_page_count(virt_to_page(trapbase_cpu2));
		free_page((unsigned long)trapbase_cpu2);
		totalram_pages++;
		num_physpages++;
	}
	if (!cpu_isset(3, cpu_present_map)) {
		ClearPageReserved(virt_to_page(trapbase_cpu3));
		init_page_count(virt_to_page(trapbase_cpu3));
		free_page((unsigned long)trapbase_cpu3);
		totalram_pages++;
		num_physpages++;
	}

	/* Ok, they are spinning and ready to go. */
}

/* At each hardware IRQ, we get this called to forward IRQ reception
 * to the next processor.  The caller must disable the IRQ level being
 * serviced globally so that there are no double interrupts received.
 *
 * XXX See sparc64 irq.c.
 */
void smp4m_irq_rotate(int cpu)
{
	int next = cpu_data(cpu).next;
	if (next != cpu)
		set_irq_udt(next);
}

/* Cross calls, in order to work efficiently and atomically do all
 * the message passing work themselves, only stopcpu and reschedule
 * messages come through here.
 */
void smp4m_message_pass(int target, int msg, unsigned long data, int wait)
{
	static unsigned long smp_cpu_in_msg[NR_CPUS];
	cpumask_t mask;
	int me = smp_processor_id();
	int irq, i;

	if(msg == MSG_RESCHEDULE) {
		irq = IRQ_RESCHEDULE;

		if(smp_cpu_in_msg[me])
			return;
	} else if(msg == MSG_STOP_CPU) {
		irq = IRQ_STOP_CPU;
	} else {
		goto barf;
	}

	smp_cpu_in_msg[me]++;
	if(target == MSG_ALL_BUT_SELF || target == MSG_ALL) {
		mask = cpu_online_map;
		if(target == MSG_ALL_BUT_SELF)
			cpu_clear(me, mask);
		for(i = 0; i < 4; i++) {
			if (cpu_isset(i, mask))
				set_cpu_int(i, irq);
		}
	} else {
		set_cpu_int(target, irq);
	}
	smp_cpu_in_msg[me]--;

	return;
barf:
	printk("Yeeee, trying to send SMP msg(%d) on cpu %d\n", msg, me);
	panic("Bogon SMP message pass.");
}

static struct smp_funcall {
	smpfunc_t func;
	unsigned long arg1;
	unsigned long arg2;
	unsigned long arg3;
	unsigned long arg4;
	unsigned long arg5;
	unsigned long processors_in[SUN4M_NCPUS];  /* Set when ipi entered. */
	unsigned long processors_out[SUN4M_NCPUS]; /* Set when ipi exited. */
} ccall_info;

static DEFINE_SPINLOCK(cross_call_lock);

/* Cross calls must be serialized, at least currently. */
void smp4m_cross_call(smpfunc_t func, unsigned long arg1, unsigned long arg2,
		    unsigned long arg3, unsigned long arg4, unsigned long arg5)
{
		register int ncpus = SUN4M_NCPUS;
		unsigned long flags;

		spin_lock_irqsave(&cross_call_lock, flags);

		/* Init function glue. */
		ccall_info.func = func;
		ccall_info.arg1 = arg1;
		ccall_info.arg2 = arg2;
		ccall_info.arg3 = arg3;
		ccall_info.arg4 = arg4;
		ccall_info.arg5 = arg5;

		/* Init receive/complete mapping, plus fire the IPI's off. */
		{
			cpumask_t mask = cpu_online_map;
			register int i;

			cpu_clear(smp_processor_id(), mask);
			for(i = 0; i < ncpus; i++) {
				if (cpu_isset(i, mask)) {
					ccall_info.processors_in[i] = 0;
					ccall_info.processors_out[i] = 0;
					set_cpu_int(i, IRQ_CROSS_CALL);
				} else {
					ccall_info.processors_in[i] = 1;
					ccall_info.processors_out[i] = 1;
				}
			}
		}

		{
			register int i;

			i = 0;
			do {
				while(!ccall_info.processors_in[i])
					barrier();
			} while(++i < ncpus);

			i = 0;
			do {
				while(!ccall_info.processors_out[i])
					barrier();
			} while(++i < ncpus);
		}

		spin_unlock_irqrestore(&cross_call_lock, flags);
}

/* Running cross calls. */
void smp4m_cross_call_irq(void)
{
	int i = smp_processor_id();

	ccall_info.processors_in[i] = 1;
	ccall_info.func(ccall_info.arg1, ccall_info.arg2, ccall_info.arg3,
			ccall_info.arg4, ccall_info.arg5);
	ccall_info.processors_out[i] = 1;
}

void smp4m_percpu_timer_interrupt(struct pt_regs *regs)
{
	struct pt_regs *old_regs;
	int cpu = smp_processor_id();

	old_regs = set_irq_regs(regs);

	clear_profile_irq(cpu);

	profile_tick(CPU_PROFILING);

	if(!--prof_counter(cpu)) {
		int user = user_mode(regs);

		irq_enter();
		update_process_times(user);
		irq_exit();

		prof_counter(cpu) = prof_multiplier(cpu);
	}
	set_irq_regs(old_regs);
}

extern unsigned int lvl14_resolution;

static void __init smp_setup_percpu_timer(void)
{
	int cpu = smp_processor_id();

	prof_counter(cpu) = prof_multiplier(cpu) = 1;
	load_profile_irq(cpu, lvl14_resolution);

	if(cpu == boot_cpu_id)
		enable_pil_irq(14);
}

void __init smp4m_blackbox_id(unsigned *addr)
{
	int rd = *addr & 0x3e000000;
	int rs1 = rd >> 11;
	
	addr[0] = 0x81580000 | rd;		/* rd %tbr, reg */
	addr[1] = 0x8130200c | rd | rs1;    	/* srl reg, 0xc, reg */
	addr[2] = 0x80082003 | rd | rs1;	/* and reg, 3, reg */
}

void __init smp4m_blackbox_current(unsigned *addr)
{
	int rd = *addr & 0x3e000000;
	int rs1 = rd >> 11;
	
	addr[0] = 0x81580000 | rd;		/* rd %tbr, reg */
	addr[2] = 0x8130200a | rd | rs1;    	/* srl reg, 0xa, reg */
	addr[4] = 0x8008200c | rd | rs1;	/* and reg, 0xc, reg */
}

void __init sun4m_init_smp(void)
{
	BTFIXUPSET_BLACKBOX(hard_smp_processor_id, smp4m_blackbox_id);
	BTFIXUPSET_BLACKBOX(load_current, smp4m_blackbox_current);
	BTFIXUPSET_CALL(smp_cross_call, smp4m_cross_call, BTFIXUPCALL_NORM);
	BTFIXUPSET_CALL(smp_message_pass, smp4m_message_pass, BTFIXUPCALL_NORM);
	BTFIXUPSET_CALL(__hard_smp_processor_id, __smp4m_processor_id, BTFIXUPCALL_NORM);
}
OpenPOWER on IntegriCloud