parisc: use sort() instead of home-made implementation (v2)
[linux-2.6-block.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>
21#include <linux/slab.h>
22
23#include <linux/kernel.h>
24#include <linux/module.h>
25#include <linux/sched.h>
26#include <linux/init.h>
27#include <linux/interrupt.h>
28#include <linux/smp.h>
29#include <linux/kernel_stat.h>
30#include <linux/mm.h>
4e950f6f 31#include <linux/err.h>
1da177e4
LT
32#include <linux/delay.h>
33#include <linux/bitops.h>
d75f054a 34#include <linux/ftrace.h>
1da177e4
LT
35
36#include <asm/system.h>
37#include <asm/atomic.h>
38#include <asm/current.h>
39#include <asm/delay.h>
1b2425e3 40#include <asm/tlbflush.h>
1da177e4
LT
41
42#include <asm/io.h>
43#include <asm/irq.h> /* for CPU_IRQ_REGION and friends */
44#include <asm/mmu_context.h>
45#include <asm/page.h>
46#include <asm/pgtable.h>
47#include <asm/pgalloc.h>
48#include <asm/processor.h>
49#include <asm/ptrace.h>
50#include <asm/unistd.h>
51#include <asm/cacheflush.h>
52
5492a0f0
KM
53#undef DEBUG_SMP
54#ifdef DEBUG_SMP
55static int smp_debug_lvl = 0;
56#define smp_debug(lvl, printargs...) \
57 if (lvl >= smp_debug_lvl) \
58 printk(printargs);
59#else
ef017beb 60#define smp_debug(lvl, ...) do { } while(0)
5492a0f0 61#endif /* DEBUG_SMP */
1da177e4
LT
62
63DEFINE_SPINLOCK(smp_lock);
64
65volatile struct task_struct *smp_init_current_idle_task;
66
ef017beb
HD
67/* track which CPU is booting */
68static volatile int cpu_now_booting __cpuinitdata;
1da177e4 69
ef017beb 70static int parisc_max_cpus __cpuinitdata = 1;
1da177e4 71
3c97b5e9 72DEFINE_PER_CPU(spinlock_t, ipi_lock) = SPIN_LOCK_UNLOCKED;
1da177e4 73
1da177e4
LT
74enum ipi_message_type {
75 IPI_NOP=0,
76 IPI_RESCHEDULE=1,
77 IPI_CALL_FUNC,
dbcf4787 78 IPI_CALL_FUNC_SINGLE,
1da177e4
LT
79 IPI_CPU_START,
80 IPI_CPU_STOP,
81 IPI_CPU_TEST
82};
83
84
85/********** SMP inter processor interrupt and communication routines */
86
87#undef PER_CPU_IRQ_REGION
88#ifdef PER_CPU_IRQ_REGION
89/* XXX REVISIT Ignore for now.
90** *May* need this "hook" to register IPI handler
91** once we have perCPU ExtIntr switch tables.
92*/
93static void
94ipi_init(int cpuid)
95{
1da177e4
LT
96#error verify IRQ_OFFSET(IPI_IRQ) is ipi_interrupt() in new IRQ region
97
98 if(cpu_online(cpuid) )
99 {
100 switch_to_idle_task(current);
101 }
102
103 return;
104}
105#endif
106
107
108/*
109** Yoink this CPU from the runnable list...
110**
111*/
112static void
113halt_processor(void)
114{
1da177e4
LT
115 /* REVISIT : redirect I/O Interrupts to another CPU? */
116 /* REVISIT : does PM *know* this CPU isn't available? */
9bc181d8 117 set_cpu_online(smp_processor_id(), false);
1da177e4
LT
118 local_irq_disable();
119 for (;;)
120 ;
1da177e4
LT
121}
122
123
d75f054a 124irqreturn_t __irq_entry
c7753f18 125ipi_interrupt(int irq, void *dev_id)
1da177e4
LT
126{
127 int this_cpu = smp_processor_id();
ef017beb 128 struct cpuinfo_parisc *p = &per_cpu(cpu_data, this_cpu);
1da177e4
LT
129 unsigned long ops;
130 unsigned long flags;
131
132 /* Count this now; we may make a call that never returns. */
133 p->ipi_count++;
134
135 mb(); /* Order interrupt and bit testing. */
136
137 for (;;) {
3c97b5e9
KM
138 spinlock_t *lock = &per_cpu(ipi_lock, this_cpu);
139 spin_lock_irqsave(lock, flags);
1da177e4
LT
140 ops = p->pending_ipi;
141 p->pending_ipi = 0;
3c97b5e9 142 spin_unlock_irqrestore(lock, flags);
1da177e4
LT
143
144 mb(); /* Order bit clearing and data access. */
145
146 if (!ops)
147 break;
148
149 while (ops) {
150 unsigned long which = ffz(~ops);
151
d911aed8
JB
152 ops &= ~(1 << which);
153
1da177e4 154 switch (which) {
d911aed8 155 case IPI_NOP:
5492a0f0 156 smp_debug(100, KERN_DEBUG "CPU%d IPI_NOP\n", this_cpu);
d911aed8
JB
157 break;
158
1da177e4 159 case IPI_RESCHEDULE:
5492a0f0 160 smp_debug(100, KERN_DEBUG "CPU%d IPI_RESCHEDULE\n", this_cpu);
1da177e4
LT
161 /*
162 * Reschedule callback. Everything to be
163 * done is done by the interrupt return path.
164 */
165 break;
166
167 case IPI_CALL_FUNC:
5492a0f0 168 smp_debug(100, KERN_DEBUG "CPU%d IPI_CALL_FUNC\n", this_cpu);
dbcf4787
JA
169 generic_smp_call_function_interrupt();
170 break;
171
172 case IPI_CALL_FUNC_SINGLE:
173 smp_debug(100, KERN_DEBUG "CPU%d IPI_CALL_FUNC_SINGLE\n", this_cpu);
174 generic_smp_call_function_single_interrupt();
1da177e4
LT
175 break;
176
177 case IPI_CPU_START:
5492a0f0 178 smp_debug(100, KERN_DEBUG "CPU%d IPI_CPU_START\n", this_cpu);
1da177e4
LT
179 break;
180
181 case IPI_CPU_STOP:
5492a0f0 182 smp_debug(100, KERN_DEBUG "CPU%d IPI_CPU_STOP\n", this_cpu);
1da177e4 183 halt_processor();
1da177e4
LT
184 break;
185
186 case IPI_CPU_TEST:
5492a0f0 187 smp_debug(100, KERN_DEBUG "CPU%d is alive!\n", this_cpu);
1da177e4
LT
188 break;
189
190 default:
191 printk(KERN_CRIT "Unknown IPI num on CPU%d: %lu\n",
192 this_cpu, which);
1da177e4
LT
193 return IRQ_NONE;
194 } /* Switch */
7085689e
JB
195 /* let in any pending interrupts */
196 local_irq_enable();
197 local_irq_disable();
1da177e4
LT
198 } /* while (ops) */
199 }
200 return IRQ_HANDLED;
201}
202
203
204static inline void
205ipi_send(int cpu, enum ipi_message_type op)
206{
ef017beb 207 struct cpuinfo_parisc *p = &per_cpu(cpu_data, cpu);
3c97b5e9 208 spinlock_t *lock = &per_cpu(ipi_lock, cpu);
1da177e4
LT
209 unsigned long flags;
210
3c97b5e9 211 spin_lock_irqsave(lock, flags);
1da177e4 212 p->pending_ipi |= 1 << op;
ef017beb 213 gsc_writel(IPI_IRQ - CPU_IRQ_BASE, p->hpa);
3c97b5e9 214 spin_unlock_irqrestore(lock, flags);
1da177e4
LT
215}
216
dbcf4787 217static void
91887a36 218send_IPI_mask(const struct cpumask *mask, enum ipi_message_type op)
dbcf4787
JA
219{
220 int cpu;
221
91887a36 222 for_each_cpu(cpu, mask)
dbcf4787
JA
223 ipi_send(cpu, op);
224}
1da177e4
LT
225
226static inline void
227send_IPI_single(int dest_cpu, enum ipi_message_type op)
228{
7f2347a4 229 BUG_ON(dest_cpu == NO_PROC_ID);
1da177e4
LT
230
231 ipi_send(dest_cpu, op);
232}
233
234static inline void
235send_IPI_allbutself(enum ipi_message_type op)
236{
237 int i;
238
394e3902
AM
239 for_each_online_cpu(i) {
240 if (i != smp_processor_id())
1da177e4
LT
241 send_IPI_single(i, op);
242 }
243}
244
245
246inline void
247smp_send_stop(void) { send_IPI_allbutself(IPI_CPU_STOP); }
248
249static inline void
250smp_send_start(void) { send_IPI_allbutself(IPI_CPU_START); }
251
252void
253smp_send_reschedule(int cpu) { send_IPI_single(cpu, IPI_RESCHEDULE); }
254
d911aed8
JB
255void
256smp_send_all_nop(void)
257{
258 send_IPI_allbutself(IPI_NOP);
259}
260
91887a36 261void arch_send_call_function_ipi_mask(const struct cpumask *mask)
1da177e4 262{
dbcf4787 263 send_IPI_mask(mask, IPI_CALL_FUNC);
1da177e4
LT
264}
265
dbcf4787
JA
266void arch_send_call_function_single_ipi(int cpu)
267{
268 send_IPI_single(cpu, IPI_CALL_FUNC_SINGLE);
269}
1da177e4
LT
270
271/*
272 * Flush all other CPU's tlb and then mine. Do this with on_each_cpu()
273 * as we want to ensure all TLB's flushed before proceeding.
274 */
275
1da177e4
LT
276void
277smp_flush_tlb_all(void)
278{
15c8b6c1 279 on_each_cpu(flush_tlb_all_local, NULL, 1);
1da177e4
LT
280}
281
1da177e4
LT
282/*
283 * Called by secondaries to update state and initialize CPU registers.
284 */
285static void __init
286smp_cpu_init(int cpunum)
287{
56f335c8 288 extern int init_per_cpu(int); /* arch/parisc/kernel/processor.c */
1da177e4 289 extern void init_IRQ(void); /* arch/parisc/kernel/irq.c */
56f335c8 290 extern void start_cpu_itimer(void); /* arch/parisc/kernel/time.c */
1da177e4
LT
291
292 /* Set modes and Enable floating point coprocessor */
293 (void) init_per_cpu(cpunum);
294
295 disable_sr_hashing();
296
297 mb();
298
299 /* Well, support 2.4 linux scheme as well. */
9bc181d8 300 if (cpu_isset(cpunum, cpu_online_map))
1da177e4
LT
301 {
302 extern void machine_halt(void); /* arch/parisc.../process.c */
303
304 printk(KERN_CRIT "CPU#%d already initialized!\n", cpunum);
305 machine_halt();
306 }
9bc181d8 307 set_cpu_online(cpunum, true);
1da177e4
LT
308
309 /* Initialise the idle task for this CPU */
310 atomic_inc(&init_mm.mm_count);
311 current->active_mm = &init_mm;
7f2347a4 312 BUG_ON(current->mm);
1da177e4
LT
313 enter_lazy_tlb(&init_mm, current);
314
7022672e 315 init_IRQ(); /* make sure no IRQs are enabled or pending */
56f335c8 316 start_cpu_itimer();
1da177e4
LT
317}
318
319
320/*
321 * Slaves start using C here. Indirectly called from smp_slave_stext.
322 * Do what start_kernel() and main() do for boot strap processor (aka monarch)
323 */
324void __init smp_callin(void)
325{
326 int slave_id = cpu_now_booting;
1da177e4
LT
327
328 smp_cpu_init(slave_id);
5bfb5d69 329 preempt_disable();
1da177e4 330
1da177e4 331 flush_cache_all_local(); /* start with known state */
1b2425e3 332 flush_tlb_all_local(NULL);
1da177e4
LT
333
334 local_irq_enable(); /* Interrupts have been off until now */
335
336 cpu_idle(); /* Wait for timer to schedule some work */
337
338 /* NOTREACHED */
339 panic("smp_callin() AAAAaaaaahhhh....\n");
340}
341
342/*
343 * Bring one cpu online.
344 */
8dff980f 345int __cpuinit smp_boot_one_cpu(int cpuid)
1da177e4 346{
ef017beb 347 const struct cpuinfo_parisc *p = &per_cpu(cpu_data, cpuid);
1da177e4
LT
348 struct task_struct *idle;
349 long timeout;
350
351 /*
352 * Create an idle task for this CPU. Note the address wed* give
353 * to kernel_thread is irrelevant -- it's going to start
354 * where OS_BOOT_RENDEVZ vector in SAL says to start. But
355 * this gets all the other task-y sort of data structures set
356 * up like we wish. We need to pull the just created idle task
357 * off the run queue and stuff it into the init_tasks[] array.
358 * Sheesh . . .
359 */
360
361 idle = fork_idle(cpuid);
362 if (IS_ERR(idle))
363 panic("SMP: fork failed for CPU:%d", cpuid);
364
40f1f0de 365 task_thread_info(idle)->cpu = cpuid;
1da177e4
LT
366
367 /* Let _start know what logical CPU we're booting
368 ** (offset into init_tasks[],cpu_data[])
369 */
370 cpu_now_booting = cpuid;
371
372 /*
373 ** boot strap code needs to know the task address since
374 ** it also contains the process stack.
375 */
376 smp_init_current_idle_task = idle ;
377 mb();
378
ef017beb 379 printk(KERN_INFO "Releasing cpu %d now, hpa=%lx\n", cpuid, p->hpa);
1da177e4
LT
380
381 /*
382 ** This gets PDC to release the CPU from a very tight loop.
383 **
384 ** From the PA-RISC 2.0 Firmware Architecture Reference Specification:
385 ** "The MEM_RENDEZ vector specifies the location of OS_RENDEZ which
386 ** is executed after receiving the rendezvous signal (an interrupt to
387 ** EIR{0}). MEM_RENDEZ is valid only when it is nonzero and the
388 ** contents of memory are valid."
389 */
ef017beb 390 gsc_writel(TIMER_IRQ - CPU_IRQ_BASE, p->hpa);
1da177e4
LT
391 mb();
392
393 /*
394 * OK, wait a bit for that CPU to finish staggering about.
395 * Slave will set a bit when it reaches smp_cpu_init().
396 * Once the "monarch CPU" sees the bit change, it can move on.
397 */
398 for (timeout = 0; timeout < 10000; timeout++) {
399 if(cpu_online(cpuid)) {
400 /* Which implies Slave has started up */
401 cpu_now_booting = 0;
402 smp_init_current_idle_task = NULL;
403 goto alive ;
404 }
405 udelay(100);
406 barrier();
407 }
408
409 put_task_struct(idle);
410 idle = NULL;
411
412 printk(KERN_CRIT "SMP: CPU:%d is stuck.\n", cpuid);
413 return -1;
414
415alive:
416 /* Remember the Slave data */
5492a0f0 417 smp_debug(100, KERN_DEBUG "SMP: CPU:%d came alive after %ld _us\n",
1da177e4 418 cpuid, timeout * 100);
1da177e4
LT
419 return 0;
420}
421
ef017beb 422void __init smp_prepare_boot_cpu(void)
1da177e4 423{
ef017beb 424 int bootstrap_processor = per_cpu(cpu_data, 0).cpuid;
1da177e4 425
1da177e4 426 /* Setup BSP mappings */
ef017beb 427 printk(KERN_INFO "SMP: bootstrap CPU ID is %d\n", bootstrap_processor);
1da177e4 428
9bc181d8
RR
429 set_cpu_online(bootstrap_processor, true);
430 set_cpu_present(bootstrap_processor, true);
1da177e4
LT
431}
432
433
434
435/*
436** inventory.c:do_inventory() hasn't yet been run and thus we
7022672e 437** don't 'discover' the additional CPUs until later.
1da177e4
LT
438*/
439void __init smp_prepare_cpus(unsigned int max_cpus)
440{
9bc181d8 441 init_cpu_present(cpumask_of(0));
1da177e4
LT
442
443 parisc_max_cpus = max_cpus;
444 if (!max_cpus)
445 printk(KERN_INFO "SMP mode deactivated.\n");
446}
447
448
449void smp_cpus_done(unsigned int cpu_max)
450{
451 return;
452}
453
454
b282b6f8 455int __cpuinit __cpu_up(unsigned int cpu)
1da177e4
LT
456{
457 if (cpu != 0 && cpu < parisc_max_cpus)
458 smp_boot_one_cpu(cpu);
459
460 return cpu_online(cpu) ? 0 : -ENOSYS;
461}
462
1da177e4
LT
463#ifdef CONFIG_PROC_FS
464int __init
465setup_profiling_timer(unsigned int multiplier)
466{
467 return -EINVAL;
468}
469#endif