Merge branch 'x86-debug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git...
[deliverable/linux.git] / arch / parisc / kernel / smp.c
CommitLineData
1da177e4
LT
1/*
2** SMP Support
3**
4** Copyright (C) 1999 Walt Drummond <drummond@valinux.com>
5** Copyright (C) 1999 David Mosberger-Tang <davidm@hpl.hp.com>
6** Copyright (C) 2001,2004 Grant Grundler <grundler@parisc-linux.org>
7**
8** Lots of stuff stolen from arch/alpha/kernel/smp.c
9** ...and then parisc stole from arch/ia64/kernel/smp.c. Thanks David! :^)
10**
7022672e 11** Thanks to John Curry and Ullas Ponnadi. I learned a lot from their work.
1da177e4
LT
12** -grant (1/12/2001)
13**
14** This program is free software; you can redistribute it and/or modify
15** it under the terms of the GNU General Public License as published by
16** the Free Software Foundation; either version 2 of the License, or
17** (at your option) any later version.
18*/
1da177e4
LT
19#include <linux/types.h>
20#include <linux/spinlock.h>
1da177e4
LT
21
22#include <linux/kernel.h>
23#include <linux/module.h>
24#include <linux/sched.h>
25#include <linux/init.h>
26#include <linux/interrupt.h>
27#include <linux/smp.h>
28#include <linux/kernel_stat.h>
29#include <linux/mm.h>
4e950f6f 30#include <linux/err.h>
1da177e4
LT
31#include <linux/delay.h>
32#include <linux/bitops.h>
d75f054a 33#include <linux/ftrace.h>
ec2e0f98 34#include <linux/cpu.h>
1da177e4 35
60063497 36#include <linux/atomic.h>
1da177e4
LT
37#include <asm/current.h>
38#include <asm/delay.h>
1b2425e3 39#include <asm/tlbflush.h>
1da177e4
LT
40
41#include <asm/io.h>
42#include <asm/irq.h> /* for CPU_IRQ_REGION and friends */
43#include <asm/mmu_context.h>
44#include <asm/page.h>
45#include <asm/pgtable.h>
46#include <asm/pgalloc.h>
47#include <asm/processor.h>
48#include <asm/ptrace.h>
49#include <asm/unistd.h>
50#include <asm/cacheflush.h>
51
5492a0f0
KM
52#undef DEBUG_SMP
53#ifdef DEBUG_SMP
54static int smp_debug_lvl = 0;
55#define smp_debug(lvl, printargs...) \
56 if (lvl >= smp_debug_lvl) \
57 printk(printargs);
58#else
ef017beb 59#define smp_debug(lvl, ...) do { } while(0)
5492a0f0 60#endif /* DEBUG_SMP */
1da177e4 61
1da177e4
LT
62volatile struct task_struct *smp_init_current_idle_task;
63
ef017beb
HD
64/* track which CPU is booting */
65static volatile int cpu_now_booting __cpuinitdata;
1da177e4 66
ef017beb 67static int parisc_max_cpus __cpuinitdata = 1;
1da177e4 68
6ad6c424 69static DEFINE_PER_CPU(spinlock_t, ipi_lock);
1da177e4 70
1da177e4
LT
71enum ipi_message_type {
72 IPI_NOP=0,
73 IPI_RESCHEDULE=1,
74 IPI_CALL_FUNC,
dbcf4787 75 IPI_CALL_FUNC_SINGLE,
1da177e4
LT
76 IPI_CPU_START,
77 IPI_CPU_STOP,
78 IPI_CPU_TEST
79};
80
81
82/********** SMP inter processor interrupt and communication routines */
83
84#undef PER_CPU_IRQ_REGION
85#ifdef PER_CPU_IRQ_REGION
86/* XXX REVISIT Ignore for now.
87** *May* need this "hook" to register IPI handler
88** once we have perCPU ExtIntr switch tables.
89*/
90static void
91ipi_init(int cpuid)
92{
1da177e4
LT
93#error verify IRQ_OFFSET(IPI_IRQ) is ipi_interrupt() in new IRQ region
94
95 if(cpu_online(cpuid) )
96 {
97 switch_to_idle_task(current);
98 }
99
100 return;
101}
102#endif
103
104
105/*
106** Yoink this CPU from the runnable list...
107**
108*/
109static void
110halt_processor(void)
111{
1da177e4
LT
112 /* REVISIT : redirect I/O Interrupts to another CPU? */
113 /* REVISIT : does PM *know* this CPU isn't available? */
9bc181d8 114 set_cpu_online(smp_processor_id(), false);
1da177e4
LT
115 local_irq_disable();
116 for (;;)
117 ;
1da177e4
LT
118}
119
120
d75f054a 121irqreturn_t __irq_entry
c7753f18 122ipi_interrupt(int irq, void *dev_id)
1da177e4
LT
123{
124 int this_cpu = smp_processor_id();
ef017beb 125 struct cpuinfo_parisc *p = &per_cpu(cpu_data, this_cpu);
1da177e4
LT
126 unsigned long ops;
127 unsigned long flags;
128
129 /* Count this now; we may make a call that never returns. */
130 p->ipi_count++;
131
132 mb(); /* Order interrupt and bit testing. */
133
134 for (;;) {
3c97b5e9
KM
135 spinlock_t *lock = &per_cpu(ipi_lock, this_cpu);
136 spin_lock_irqsave(lock, flags);
1da177e4
LT
137 ops = p->pending_ipi;
138 p->pending_ipi = 0;
3c97b5e9 139 spin_unlock_irqrestore(lock, flags);
1da177e4
LT
140
141 mb(); /* Order bit clearing and data access. */
142
143 if (!ops)
144 break;
145
146 while (ops) {
147 unsigned long which = ffz(~ops);
148
d911aed8
JB
149 ops &= ~(1 << which);
150
1da177e4 151 switch (which) {
d911aed8 152 case IPI_NOP:
5492a0f0 153 smp_debug(100, KERN_DEBUG "CPU%d IPI_NOP\n", this_cpu);
d911aed8
JB
154 break;
155
1da177e4 156 case IPI_RESCHEDULE:
5492a0f0 157 smp_debug(100, KERN_DEBUG "CPU%d IPI_RESCHEDULE\n", this_cpu);
184748cc 158 scheduler_ipi();
1da177e4
LT
159 break;
160
161 case IPI_CALL_FUNC:
5492a0f0 162 smp_debug(100, KERN_DEBUG "CPU%d IPI_CALL_FUNC\n", this_cpu);
dbcf4787
JA
163 generic_smp_call_function_interrupt();
164 break;
165
166 case IPI_CALL_FUNC_SINGLE:
167 smp_debug(100, KERN_DEBUG "CPU%d IPI_CALL_FUNC_SINGLE\n", this_cpu);
168 generic_smp_call_function_single_interrupt();
1da177e4
LT
169 break;
170
171 case IPI_CPU_START:
5492a0f0 172 smp_debug(100, KERN_DEBUG "CPU%d IPI_CPU_START\n", this_cpu);
1da177e4
LT
173 break;
174
175 case IPI_CPU_STOP:
5492a0f0 176 smp_debug(100, KERN_DEBUG "CPU%d IPI_CPU_STOP\n", this_cpu);
1da177e4 177 halt_processor();
1da177e4
LT
178 break;
179
180 case IPI_CPU_TEST:
5492a0f0 181 smp_debug(100, KERN_DEBUG "CPU%d is alive!\n", this_cpu);
1da177e4
LT
182 break;
183
184 default:
185 printk(KERN_CRIT "Unknown IPI num on CPU%d: %lu\n",
186 this_cpu, which);
1da177e4
LT
187 return IRQ_NONE;
188 } /* Switch */
7085689e
JB
189 /* let in any pending interrupts */
190 local_irq_enable();
191 local_irq_disable();
1da177e4
LT
192 } /* while (ops) */
193 }
194 return IRQ_HANDLED;
195}
196
197
198static inline void
199ipi_send(int cpu, enum ipi_message_type op)
200{
ef017beb 201 struct cpuinfo_parisc *p = &per_cpu(cpu_data, cpu);
3c97b5e9 202 spinlock_t *lock = &per_cpu(ipi_lock, cpu);
1da177e4
LT
203 unsigned long flags;
204
3c97b5e9 205 spin_lock_irqsave(lock, flags);
1da177e4 206 p->pending_ipi |= 1 << op;
ef017beb 207 gsc_writel(IPI_IRQ - CPU_IRQ_BASE, p->hpa);
3c97b5e9 208 spin_unlock_irqrestore(lock, flags);
1da177e4
LT
209}
210
dbcf4787 211static void
91887a36 212send_IPI_mask(const struct cpumask *mask, enum ipi_message_type op)
dbcf4787
JA
213{
214 int cpu;
215
91887a36 216 for_each_cpu(cpu, mask)
dbcf4787
JA
217 ipi_send(cpu, op);
218}
1da177e4
LT
219
220static inline void
221send_IPI_single(int dest_cpu, enum ipi_message_type op)
222{
7f2347a4 223 BUG_ON(dest_cpu == NO_PROC_ID);
1da177e4
LT
224
225 ipi_send(dest_cpu, op);
226}
227
228static inline void
229send_IPI_allbutself(enum ipi_message_type op)
230{
231 int i;
232
394e3902
AM
233 for_each_online_cpu(i) {
234 if (i != smp_processor_id())
1da177e4
LT
235 send_IPI_single(i, op);
236 }
237}
238
239
240inline void
241smp_send_stop(void) { send_IPI_allbutself(IPI_CPU_STOP); }
242
243static inline void
244smp_send_start(void) { send_IPI_allbutself(IPI_CPU_START); }
245
246void
247smp_send_reschedule(int cpu) { send_IPI_single(cpu, IPI_RESCHEDULE); }
248
d911aed8
JB
249void
250smp_send_all_nop(void)
251{
252 send_IPI_allbutself(IPI_NOP);
253}
254
91887a36 255void arch_send_call_function_ipi_mask(const struct cpumask *mask)
1da177e4 256{
dbcf4787 257 send_IPI_mask(mask, IPI_CALL_FUNC);
1da177e4
LT
258}
259
dbcf4787
JA
260void arch_send_call_function_single_ipi(int cpu)
261{
262 send_IPI_single(cpu, IPI_CALL_FUNC_SINGLE);
263}
1da177e4
LT
264
265/*
266 * Flush all other CPU's tlb and then mine. Do this with on_each_cpu()
267 * as we want to ensure all TLB's flushed before proceeding.
268 */
269
1da177e4
LT
270void
271smp_flush_tlb_all(void)
272{
15c8b6c1 273 on_each_cpu(flush_tlb_all_local, NULL, 1);
1da177e4
LT
274}
275
1da177e4
LT
276/*
277 * Called by secondaries to update state and initialize CPU registers.
278 */
279static void __init
280smp_cpu_init(int cpunum)
281{
56f335c8 282 extern int init_per_cpu(int); /* arch/parisc/kernel/processor.c */
1da177e4 283 extern void init_IRQ(void); /* arch/parisc/kernel/irq.c */
56f335c8 284 extern void start_cpu_itimer(void); /* arch/parisc/kernel/time.c */
1da177e4
LT
285
286 /* Set modes and Enable floating point coprocessor */
287 (void) init_per_cpu(cpunum);
288
289 disable_sr_hashing();
290
291 mb();
292
293 /* Well, support 2.4 linux scheme as well. */
7ec6118c 294 if (cpu_online(cpunum)) {
1da177e4
LT
295 extern void machine_halt(void); /* arch/parisc.../process.c */
296
297 printk(KERN_CRIT "CPU#%d already initialized!\n", cpunum);
298 machine_halt();
ec2e0f98
SB
299 }
300
301 notify_cpu_starting(cpunum);
302
9bc181d8 303 set_cpu_online(cpunum, true);
1da177e4
LT
304
305 /* Initialise the idle task for this CPU */
306 atomic_inc(&init_mm.mm_count);
307 current->active_mm = &init_mm;
7f2347a4 308 BUG_ON(current->mm);
1da177e4
LT
309 enter_lazy_tlb(&init_mm, current);
310
7022672e 311 init_IRQ(); /* make sure no IRQs are enabled or pending */
56f335c8 312 start_cpu_itimer();
1da177e4
LT
313}
314
315
316/*
317 * Slaves start using C here. Indirectly called from smp_slave_stext.
318 * Do what start_kernel() and main() do for boot strap processor (aka monarch)
319 */
320void __init smp_callin(void)
321{
322 int slave_id = cpu_now_booting;
1da177e4
LT
323
324 smp_cpu_init(slave_id);
5bfb5d69 325 preempt_disable();
1da177e4 326
1da177e4 327 flush_cache_all_local(); /* start with known state */
1b2425e3 328 flush_tlb_all_local(NULL);
1da177e4
LT
329
330 local_irq_enable(); /* Interrupts have been off until now */
331
332 cpu_idle(); /* Wait for timer to schedule some work */
333
334 /* NOTREACHED */
335 panic("smp_callin() AAAAaaaaahhhh....\n");
336}
337
338/*
339 * Bring one cpu online.
340 */
9a134723 341int __cpuinit smp_boot_one_cpu(int cpuid, struct task_struct *idle)
1da177e4 342{
ef017beb 343 const struct cpuinfo_parisc *p = &per_cpu(cpu_data, cpuid);
1da177e4
LT
344 long timeout;
345
40f1f0de 346 task_thread_info(idle)->cpu = cpuid;
1da177e4
LT
347
348 /* Let _start know what logical CPU we're booting
349 ** (offset into init_tasks[],cpu_data[])
350 */
351 cpu_now_booting = cpuid;
352
353 /*
354 ** boot strap code needs to know the task address since
355 ** it also contains the process stack.
356 */
357 smp_init_current_idle_task = idle ;
358 mb();
359
ef017beb 360 printk(KERN_INFO "Releasing cpu %d now, hpa=%lx\n", cpuid, p->hpa);
1da177e4
LT
361
362 /*
363 ** This gets PDC to release the CPU from a very tight loop.
364 **
365 ** From the PA-RISC 2.0 Firmware Architecture Reference Specification:
366 ** "The MEM_RENDEZ vector specifies the location of OS_RENDEZ which
367 ** is executed after receiving the rendezvous signal (an interrupt to
368 ** EIR{0}). MEM_RENDEZ is valid only when it is nonzero and the
369 ** contents of memory are valid."
370 */
ef017beb 371 gsc_writel(TIMER_IRQ - CPU_IRQ_BASE, p->hpa);
1da177e4
LT
372 mb();
373
374 /*
375 * OK, wait a bit for that CPU to finish staggering about.
376 * Slave will set a bit when it reaches smp_cpu_init().
377 * Once the "monarch CPU" sees the bit change, it can move on.
378 */
379 for (timeout = 0; timeout < 10000; timeout++) {
380 if(cpu_online(cpuid)) {
381 /* Which implies Slave has started up */
382 cpu_now_booting = 0;
383 smp_init_current_idle_task = NULL;
384 goto alive ;
385 }
386 udelay(100);
387 barrier();
388 }
1da177e4
LT
389 printk(KERN_CRIT "SMP: CPU:%d is stuck.\n", cpuid);
390 return -1;
391
392alive:
393 /* Remember the Slave data */
5492a0f0 394 smp_debug(100, KERN_DEBUG "SMP: CPU:%d came alive after %ld _us\n",
1da177e4 395 cpuid, timeout * 100);
1da177e4
LT
396 return 0;
397}
398
ef017beb 399void __init smp_prepare_boot_cpu(void)
1da177e4 400{
ef017beb 401 int bootstrap_processor = per_cpu(cpu_data, 0).cpuid;
1da177e4 402
1da177e4 403 /* Setup BSP mappings */
ef017beb 404 printk(KERN_INFO "SMP: bootstrap CPU ID is %d\n", bootstrap_processor);
1da177e4 405
9bc181d8
RR
406 set_cpu_online(bootstrap_processor, true);
407 set_cpu_present(bootstrap_processor, true);
1da177e4
LT
408}
409
410
411
412/*
413** inventory.c:do_inventory() hasn't yet been run and thus we
7022672e 414** don't 'discover' the additional CPUs until later.
1da177e4
LT
415*/
416void __init smp_prepare_cpus(unsigned int max_cpus)
417{
6ad6c424
TG
418 int cpu;
419
420 for_each_possible_cpu(cpu)
421 spin_lock_init(&per_cpu(ipi_lock, cpu));
422
9bc181d8 423 init_cpu_present(cpumask_of(0));
1da177e4
LT
424
425 parisc_max_cpus = max_cpus;
426 if (!max_cpus)
427 printk(KERN_INFO "SMP mode deactivated.\n");
428}
429
430
431void smp_cpus_done(unsigned int cpu_max)
432{
433 return;
434}
435
436
8239c25f 437int __cpuinit __cpu_up(unsigned int cpu, struct task_struct *tidle)
1da177e4
LT
438{
439 if (cpu != 0 && cpu < parisc_max_cpus)
9a134723 440 smp_boot_one_cpu(cpu, tidle);
1da177e4
LT
441
442 return cpu_online(cpu) ? 0 : -ENOSYS;
443}
444
1da177e4
LT
445#ifdef CONFIG_PROC_FS
446int __init
447setup_profiling_timer(unsigned int multiplier)
448{
449 return -EINVAL;
450}
451#endif
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