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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3** SMP Support
4**
5** Copyright (C) 1999 Walt Drummond <drummond@valinux.com>
6** Copyright (C) 1999 David Mosberger-Tang <davidm@hpl.hp.com>
7** Copyright (C) 2001,2004 Grant Grundler <grundler@parisc-linux.org>
8**
9** Lots of stuff stolen from arch/alpha/kernel/smp.c
10** ...and then parisc stole from arch/ia64/kernel/smp.c. Thanks David! :^)
11**
12** Thanks to John Curry and Ullas Ponnadi. I learned a lot from their work.
13** -grant (1/12/2001)
14**
15*/
16#include <linux/types.h>
17#include <linux/spinlock.h>
18
19#include <linux/kernel.h>
20#include <linux/module.h>
21#include <linux/sched/mm.h>
22#include <linux/init.h>
23#include <linux/interrupt.h>
24#include <linux/smp.h>
25#include <linux/kernel_stat.h>
26#include <linux/mm.h>
27#include <linux/err.h>
28#include <linux/delay.h>
29#include <linux/bitops.h>
30#include <linux/ftrace.h>
31#include <linux/cpu.h>
32
33#include <linux/atomic.h>
34#include <asm/current.h>
35#include <asm/delay.h>
36#include <asm/tlbflush.h>
37
38#include <asm/io.h>
39#include <asm/irq.h> /* for CPU_IRQ_REGION and friends */
40#include <asm/mmu_context.h>
41#include <asm/page.h>
42#include <asm/processor.h>
43#include <asm/ptrace.h>
44#include <asm/unistd.h>
45#include <asm/cacheflush.h>
46
47#undef DEBUG_SMP
48#ifdef DEBUG_SMP
49static int smp_debug_lvl = 0;
50#define smp_debug(lvl, printargs...) \
51 if (lvl >= smp_debug_lvl) \
52 printk(printargs);
53#else
54#define smp_debug(lvl, ...) do { } while(0)
55#endif /* DEBUG_SMP */
56
57volatile struct task_struct *smp_init_current_idle_task;
58
59/* track which CPU is booting */
60static volatile int cpu_now_booting;
61
62static int parisc_max_cpus = 1;
63
64static DEFINE_PER_CPU(spinlock_t, ipi_lock);
65
66enum ipi_message_type {
67 IPI_NOP=0,
68 IPI_RESCHEDULE=1,
69 IPI_CALL_FUNC,
70 IPI_CPU_START,
71 IPI_CPU_STOP,
72 IPI_CPU_TEST
73};
74
75
76/********** SMP inter processor interrupt and communication routines */
77
78#undef PER_CPU_IRQ_REGION
79#ifdef PER_CPU_IRQ_REGION
80/* XXX REVISIT Ignore for now.
81** *May* need this "hook" to register IPI handler
82** once we have perCPU ExtIntr switch tables.
83*/
84static void
85ipi_init(int cpuid)
86{
87#error verify IRQ_OFFSET(IPI_IRQ) is ipi_interrupt() in new IRQ region
88
89 if(cpu_online(cpuid) )
90 {
91 switch_to_idle_task(current);
92 }
93
94 return;
95}
96#endif
97
98
99/*
100** Yoink this CPU from the runnable list...
101**
102*/
103static void
104halt_processor(void)
105{
106 /* REVISIT : redirect I/O Interrupts to another CPU? */
107 /* REVISIT : does PM *know* this CPU isn't available? */
108 set_cpu_online(smp_processor_id(), false);
109 local_irq_disable();
110 __pdc_cpu_rendezvous();
111 for (;;)
112 ;
113}
114
115
116irqreturn_t __irq_entry
117ipi_interrupt(int irq, void *dev_id)
118{
119 int this_cpu = smp_processor_id();
120 struct cpuinfo_parisc *p = &per_cpu(cpu_data, this_cpu);
121 unsigned long ops;
122 unsigned long flags;
123
124 for (;;) {
125 spinlock_t *lock = &per_cpu(ipi_lock, this_cpu);
126 spin_lock_irqsave(lock, flags);
127 ops = p->pending_ipi;
128 p->pending_ipi = 0;
129 spin_unlock_irqrestore(lock, flags);
130
131 mb(); /* Order bit clearing and data access. */
132
133 if (!ops)
134 break;
135
136 while (ops) {
137 unsigned long which = ffz(~ops);
138
139 ops &= ~(1 << which);
140
141 switch (which) {
142 case IPI_NOP:
143 smp_debug(100, KERN_DEBUG "CPU%d IPI_NOP\n", this_cpu);
144 break;
145
146 case IPI_RESCHEDULE:
147 smp_debug(100, KERN_DEBUG "CPU%d IPI_RESCHEDULE\n", this_cpu);
148 inc_irq_stat(irq_resched_count);
149 scheduler_ipi();
150 break;
151
152 case IPI_CALL_FUNC:
153 smp_debug(100, KERN_DEBUG "CPU%d IPI_CALL_FUNC\n", this_cpu);
154 inc_irq_stat(irq_call_count);
155 generic_smp_call_function_interrupt();
156 break;
157
158 case IPI_CPU_START:
159 smp_debug(100, KERN_DEBUG "CPU%d IPI_CPU_START\n", this_cpu);
160 break;
161
162 case IPI_CPU_STOP:
163 smp_debug(100, KERN_DEBUG "CPU%d IPI_CPU_STOP\n", this_cpu);
164 halt_processor();
165 break;
166
167 case IPI_CPU_TEST:
168 smp_debug(100, KERN_DEBUG "CPU%d is alive!\n", this_cpu);
169 break;
170
171 default:
172 printk(KERN_CRIT "Unknown IPI num on CPU%d: %lu\n",
173 this_cpu, which);
174 return IRQ_NONE;
175 } /* Switch */
176 /* let in any pending interrupts */
177 local_irq_enable();
178 local_irq_disable();
179 } /* while (ops) */
180 }
181 return IRQ_HANDLED;
182}
183
184
185static inline void
186ipi_send(int cpu, enum ipi_message_type op)
187{
188 struct cpuinfo_parisc *p = &per_cpu(cpu_data, cpu);
189 spinlock_t *lock = &per_cpu(ipi_lock, cpu);
190 unsigned long flags;
191
192 spin_lock_irqsave(lock, flags);
193 p->pending_ipi |= 1 << op;
194 gsc_writel(IPI_IRQ - CPU_IRQ_BASE, p->hpa);
195 spin_unlock_irqrestore(lock, flags);
196}
197
198static void
199send_IPI_mask(const struct cpumask *mask, enum ipi_message_type op)
200{
201 int cpu;
202
203 for_each_cpu(cpu, mask)
204 ipi_send(cpu, op);
205}
206
207static inline void
208send_IPI_single(int dest_cpu, enum ipi_message_type op)
209{
210 BUG_ON(dest_cpu == NO_PROC_ID);
211
212 ipi_send(dest_cpu, op);
213}
214
215static inline void
216send_IPI_allbutself(enum ipi_message_type op)
217{
218 int i;
219
220 for_each_online_cpu(i) {
221 if (i != smp_processor_id())
222 send_IPI_single(i, op);
223 }
224}
225
226
227inline void
228smp_send_stop(void) { send_IPI_allbutself(IPI_CPU_STOP); }
229
230void
231smp_send_reschedule(int cpu) { send_IPI_single(cpu, IPI_RESCHEDULE); }
232
233void
234smp_send_all_nop(void)
235{
236 send_IPI_allbutself(IPI_NOP);
237}
238
239void arch_send_call_function_ipi_mask(const struct cpumask *mask)
240{
241 send_IPI_mask(mask, IPI_CALL_FUNC);
242}
243
244void arch_send_call_function_single_ipi(int cpu)
245{
246 send_IPI_single(cpu, IPI_CALL_FUNC);
247}
248
249/*
250 * Called by secondaries to update state and initialize CPU registers.
251 */
252static void __init
253smp_cpu_init(int cpunum)
254{
255 extern void init_IRQ(void); /* arch/parisc/kernel/irq.c */
256 extern void start_cpu_itimer(void); /* arch/parisc/kernel/time.c */
257
258 /* Set modes and Enable floating point coprocessor */
259 init_per_cpu(cpunum);
260
261 disable_sr_hashing();
262
263 mb();
264
265 /* Well, support 2.4 linux scheme as well. */
266 if (cpu_online(cpunum)) {
267 extern void machine_halt(void); /* arch/parisc.../process.c */
268
269 printk(KERN_CRIT "CPU#%d already initialized!\n", cpunum);
270 machine_halt();
271 }
272
273 notify_cpu_starting(cpunum);
274
275 set_cpu_online(cpunum, true);
276
277 /* Initialise the idle task for this CPU */
278 mmgrab(&init_mm);
279 current->active_mm = &init_mm;
280 BUG_ON(current->mm);
281 enter_lazy_tlb(&init_mm, current);
282
283 init_IRQ(); /* make sure no IRQs are enabled or pending */
284 start_cpu_itimer();
285}
286
287
288/*
289 * Slaves start using C here. Indirectly called from smp_slave_stext.
290 * Do what start_kernel() and main() do for boot strap processor (aka monarch)
291 */
292void __init smp_callin(unsigned long pdce_proc)
293{
294 int slave_id = cpu_now_booting;
295
296#ifdef CONFIG_64BIT
297 WARN_ON(((unsigned long)(PAGE0->mem_pdc_hi) << 32
298 | PAGE0->mem_pdc) != pdce_proc);
299#endif
300
301 smp_cpu_init(slave_id);
302 preempt_disable();
303
304 flush_cache_all_local(); /* start with known state */
305 flush_tlb_all_local(NULL);
306
307 local_irq_enable(); /* Interrupts have been off until now */
308
309 cpu_startup_entry(CPUHP_AP_ONLINE_IDLE);
310
311 /* NOTREACHED */
312 panic("smp_callin() AAAAaaaaahhhh....\n");
313}
314
315/*
316 * Bring one cpu online.
317 */
318int smp_boot_one_cpu(int cpuid, struct task_struct *idle)
319{
320 const struct cpuinfo_parisc *p = &per_cpu(cpu_data, cpuid);
321 long timeout;
322
323 task_thread_info(idle)->cpu = cpuid;
324
325 /* Let _start know what logical CPU we're booting
326 ** (offset into init_tasks[],cpu_data[])
327 */
328 cpu_now_booting = cpuid;
329
330 /*
331 ** boot strap code needs to know the task address since
332 ** it also contains the process stack.
333 */
334 smp_init_current_idle_task = idle ;
335 mb();
336
337 printk(KERN_INFO "Releasing cpu %d now, hpa=%lx\n", cpuid, p->hpa);
338
339 /*
340 ** This gets PDC to release the CPU from a very tight loop.
341 **
342 ** From the PA-RISC 2.0 Firmware Architecture Reference Specification:
343 ** "The MEM_RENDEZ vector specifies the location of OS_RENDEZ which
344 ** is executed after receiving the rendezvous signal (an interrupt to
345 ** EIR{0}). MEM_RENDEZ is valid only when it is nonzero and the
346 ** contents of memory are valid."
347 */
348 gsc_writel(TIMER_IRQ - CPU_IRQ_BASE, p->hpa);
349 mb();
350
351 /*
352 * OK, wait a bit for that CPU to finish staggering about.
353 * Slave will set a bit when it reaches smp_cpu_init().
354 * Once the "monarch CPU" sees the bit change, it can move on.
355 */
356 for (timeout = 0; timeout < 10000; timeout++) {
357 if(cpu_online(cpuid)) {
358 /* Which implies Slave has started up */
359 cpu_now_booting = 0;
360 smp_init_current_idle_task = NULL;
361 goto alive ;
362 }
363 udelay(100);
364 barrier();
365 }
366 printk(KERN_CRIT "SMP: CPU:%d is stuck.\n", cpuid);
367 return -1;
368
369alive:
370 /* Remember the Slave data */
371 smp_debug(100, KERN_DEBUG "SMP: CPU:%d came alive after %ld _us\n",
372 cpuid, timeout * 100);
373 return 0;
374}
375
376void __init smp_prepare_boot_cpu(void)
377{
378 int bootstrap_processor = per_cpu(cpu_data, 0).cpuid;
379
380 /* Setup BSP mappings */
381 printk(KERN_INFO "SMP: bootstrap CPU ID is %d\n", bootstrap_processor);
382
383 set_cpu_online(bootstrap_processor, true);
384 set_cpu_present(bootstrap_processor, true);
385}
386
387
388
389/*
390** inventory.c:do_inventory() hasn't yet been run and thus we
391** don't 'discover' the additional CPUs until later.
392*/
393void __init smp_prepare_cpus(unsigned int max_cpus)
394{
395 int cpu;
396
397 for_each_possible_cpu(cpu)
398 spin_lock_init(&per_cpu(ipi_lock, cpu));
399
400 init_cpu_present(cpumask_of(0));
401
402 parisc_max_cpus = max_cpus;
403 if (!max_cpus)
404 printk(KERN_INFO "SMP mode deactivated.\n");
405}
406
407
408void smp_cpus_done(unsigned int cpu_max)
409{
410 return;
411}
412
413
414int __cpu_up(unsigned int cpu, struct task_struct *tidle)
415{
416 if (cpu != 0 && cpu < parisc_max_cpus && smp_boot_one_cpu(cpu, tidle))
417 return -ENOSYS;
418
419 return cpu_online(cpu) ? 0 : -ENOSYS;
420}
421
422#ifdef CONFIG_PROC_FS
423int setup_profiling_timer(unsigned int multiplier)
424{
425 return -EINVAL;
426}
427#endif
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**
11** Thanks to John Curry and Ullas Ponnadi. I learned a lot from their work.
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*/
19#include <linux/types.h>
20#include <linux/spinlock.h>
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>
30#include <linux/err.h>
31#include <linux/delay.h>
32#include <linux/bitops.h>
33#include <linux/ftrace.h>
34#include <linux/cpu.h>
35
36#include <linux/atomic.h>
37#include <asm/current.h>
38#include <asm/delay.h>
39#include <asm/tlbflush.h>
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
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
59#define smp_debug(lvl, ...) do { } while(0)
60#endif /* DEBUG_SMP */
61
62volatile struct task_struct *smp_init_current_idle_task;
63
64/* track which CPU is booting */
65static volatile int cpu_now_booting;
66
67static int parisc_max_cpus = 1;
68
69static DEFINE_PER_CPU(spinlock_t, ipi_lock);
70
71enum ipi_message_type {
72 IPI_NOP=0,
73 IPI_RESCHEDULE=1,
74 IPI_CALL_FUNC,
75 IPI_CPU_START,
76 IPI_CPU_STOP,
77 IPI_CPU_TEST
78};
79
80
81/********** SMP inter processor interrupt and communication routines */
82
83#undef PER_CPU_IRQ_REGION
84#ifdef PER_CPU_IRQ_REGION
85/* XXX REVISIT Ignore for now.
86** *May* need this "hook" to register IPI handler
87** once we have perCPU ExtIntr switch tables.
88*/
89static void
90ipi_init(int cpuid)
91{
92#error verify IRQ_OFFSET(IPI_IRQ) is ipi_interrupt() in new IRQ region
93
94 if(cpu_online(cpuid) )
95 {
96 switch_to_idle_task(current);
97 }
98
99 return;
100}
101#endif
102
103
104/*
105** Yoink this CPU from the runnable list...
106**
107*/
108static void
109halt_processor(void)
110{
111 /* REVISIT : redirect I/O Interrupts to another CPU? */
112 /* REVISIT : does PM *know* this CPU isn't available? */
113 set_cpu_online(smp_processor_id(), false);
114 local_irq_disable();
115 for (;;)
116 ;
117}
118
119
120irqreturn_t __irq_entry
121ipi_interrupt(int irq, void *dev_id)
122{
123 int this_cpu = smp_processor_id();
124 struct cpuinfo_parisc *p = &per_cpu(cpu_data, this_cpu);
125 unsigned long ops;
126 unsigned long flags;
127
128 for (;;) {
129 spinlock_t *lock = &per_cpu(ipi_lock, this_cpu);
130 spin_lock_irqsave(lock, flags);
131 ops = p->pending_ipi;
132 p->pending_ipi = 0;
133 spin_unlock_irqrestore(lock, flags);
134
135 mb(); /* Order bit clearing and data access. */
136
137 if (!ops)
138 break;
139
140 while (ops) {
141 unsigned long which = ffz(~ops);
142
143 ops &= ~(1 << which);
144
145 switch (which) {
146 case IPI_NOP:
147 smp_debug(100, KERN_DEBUG "CPU%d IPI_NOP\n", this_cpu);
148 break;
149
150 case IPI_RESCHEDULE:
151 smp_debug(100, KERN_DEBUG "CPU%d IPI_RESCHEDULE\n", this_cpu);
152 inc_irq_stat(irq_resched_count);
153 scheduler_ipi();
154 break;
155
156 case IPI_CALL_FUNC:
157 smp_debug(100, KERN_DEBUG "CPU%d IPI_CALL_FUNC\n", this_cpu);
158 generic_smp_call_function_interrupt();
159 break;
160
161 case IPI_CPU_START:
162 smp_debug(100, KERN_DEBUG "CPU%d IPI_CPU_START\n", this_cpu);
163 break;
164
165 case IPI_CPU_STOP:
166 smp_debug(100, KERN_DEBUG "CPU%d IPI_CPU_STOP\n", this_cpu);
167 halt_processor();
168 break;
169
170 case IPI_CPU_TEST:
171 smp_debug(100, KERN_DEBUG "CPU%d is alive!\n", this_cpu);
172 break;
173
174 default:
175 printk(KERN_CRIT "Unknown IPI num on CPU%d: %lu\n",
176 this_cpu, which);
177 return IRQ_NONE;
178 } /* Switch */
179 /* let in any pending interrupts */
180 local_irq_enable();
181 local_irq_disable();
182 } /* while (ops) */
183 }
184 return IRQ_HANDLED;
185}
186
187
188static inline void
189ipi_send(int cpu, enum ipi_message_type op)
190{
191 struct cpuinfo_parisc *p = &per_cpu(cpu_data, cpu);
192 spinlock_t *lock = &per_cpu(ipi_lock, cpu);
193 unsigned long flags;
194
195 spin_lock_irqsave(lock, flags);
196 p->pending_ipi |= 1 << op;
197 gsc_writel(IPI_IRQ - CPU_IRQ_BASE, p->hpa);
198 spin_unlock_irqrestore(lock, flags);
199}
200
201static void
202send_IPI_mask(const struct cpumask *mask, enum ipi_message_type op)
203{
204 int cpu;
205
206 for_each_cpu(cpu, mask)
207 ipi_send(cpu, op);
208}
209
210static inline void
211send_IPI_single(int dest_cpu, enum ipi_message_type op)
212{
213 BUG_ON(dest_cpu == NO_PROC_ID);
214
215 ipi_send(dest_cpu, op);
216}
217
218static inline void
219send_IPI_allbutself(enum ipi_message_type op)
220{
221 int i;
222
223 for_each_online_cpu(i) {
224 if (i != smp_processor_id())
225 send_IPI_single(i, op);
226 }
227}
228
229
230inline void
231smp_send_stop(void) { send_IPI_allbutself(IPI_CPU_STOP); }
232
233static inline void
234smp_send_start(void) { send_IPI_allbutself(IPI_CPU_START); }
235
236void
237smp_send_reschedule(int cpu) { send_IPI_single(cpu, IPI_RESCHEDULE); }
238
239void
240smp_send_all_nop(void)
241{
242 send_IPI_allbutself(IPI_NOP);
243}
244
245void arch_send_call_function_ipi_mask(const struct cpumask *mask)
246{
247 send_IPI_mask(mask, IPI_CALL_FUNC);
248}
249
250void arch_send_call_function_single_ipi(int cpu)
251{
252 send_IPI_single(cpu, IPI_CALL_FUNC);
253}
254
255/*
256 * Called by secondaries to update state and initialize CPU registers.
257 */
258static void __init
259smp_cpu_init(int cpunum)
260{
261 extern int init_per_cpu(int); /* arch/parisc/kernel/processor.c */
262 extern void init_IRQ(void); /* arch/parisc/kernel/irq.c */
263 extern void start_cpu_itimer(void); /* arch/parisc/kernel/time.c */
264
265 /* Set modes and Enable floating point coprocessor */
266 (void) init_per_cpu(cpunum);
267
268 disable_sr_hashing();
269
270 mb();
271
272 /* Well, support 2.4 linux scheme as well. */
273 if (cpu_online(cpunum)) {
274 extern void machine_halt(void); /* arch/parisc.../process.c */
275
276 printk(KERN_CRIT "CPU#%d already initialized!\n", cpunum);
277 machine_halt();
278 }
279
280 notify_cpu_starting(cpunum);
281
282 set_cpu_online(cpunum, true);
283
284 /* Initialise the idle task for this CPU */
285 atomic_inc(&init_mm.mm_count);
286 current->active_mm = &init_mm;
287 BUG_ON(current->mm);
288 enter_lazy_tlb(&init_mm, current);
289
290 init_IRQ(); /* make sure no IRQs are enabled or pending */
291 start_cpu_itimer();
292}
293
294
295/*
296 * Slaves start using C here. Indirectly called from smp_slave_stext.
297 * Do what start_kernel() and main() do for boot strap processor (aka monarch)
298 */
299void __init smp_callin(void)
300{
301 int slave_id = cpu_now_booting;
302
303 smp_cpu_init(slave_id);
304 preempt_disable();
305
306 flush_cache_all_local(); /* start with known state */
307 flush_tlb_all_local(NULL);
308
309 local_irq_enable(); /* Interrupts have been off until now */
310
311 cpu_startup_entry(CPUHP_ONLINE);
312
313 /* NOTREACHED */
314 panic("smp_callin() AAAAaaaaahhhh....\n");
315}
316
317/*
318 * Bring one cpu online.
319 */
320int smp_boot_one_cpu(int cpuid, struct task_struct *idle)
321{
322 const struct cpuinfo_parisc *p = &per_cpu(cpu_data, cpuid);
323 long timeout;
324
325 task_thread_info(idle)->cpu = cpuid;
326
327 /* Let _start know what logical CPU we're booting
328 ** (offset into init_tasks[],cpu_data[])
329 */
330 cpu_now_booting = cpuid;
331
332 /*
333 ** boot strap code needs to know the task address since
334 ** it also contains the process stack.
335 */
336 smp_init_current_idle_task = idle ;
337 mb();
338
339 printk(KERN_INFO "Releasing cpu %d now, hpa=%lx\n", cpuid, p->hpa);
340
341 /*
342 ** This gets PDC to release the CPU from a very tight loop.
343 **
344 ** From the PA-RISC 2.0 Firmware Architecture Reference Specification:
345 ** "The MEM_RENDEZ vector specifies the location of OS_RENDEZ which
346 ** is executed after receiving the rendezvous signal (an interrupt to
347 ** EIR{0}). MEM_RENDEZ is valid only when it is nonzero and the
348 ** contents of memory are valid."
349 */
350 gsc_writel(TIMER_IRQ - CPU_IRQ_BASE, p->hpa);
351 mb();
352
353 /*
354 * OK, wait a bit for that CPU to finish staggering about.
355 * Slave will set a bit when it reaches smp_cpu_init().
356 * Once the "monarch CPU" sees the bit change, it can move on.
357 */
358 for (timeout = 0; timeout < 10000; timeout++) {
359 if(cpu_online(cpuid)) {
360 /* Which implies Slave has started up */
361 cpu_now_booting = 0;
362 smp_init_current_idle_task = NULL;
363 goto alive ;
364 }
365 udelay(100);
366 barrier();
367 }
368 printk(KERN_CRIT "SMP: CPU:%d is stuck.\n", cpuid);
369 return -1;
370
371alive:
372 /* Remember the Slave data */
373 smp_debug(100, KERN_DEBUG "SMP: CPU:%d came alive after %ld _us\n",
374 cpuid, timeout * 100);
375 return 0;
376}
377
378void __init smp_prepare_boot_cpu(void)
379{
380 int bootstrap_processor = per_cpu(cpu_data, 0).cpuid;
381
382 /* Setup BSP mappings */
383 printk(KERN_INFO "SMP: bootstrap CPU ID is %d\n", bootstrap_processor);
384
385 set_cpu_online(bootstrap_processor, true);
386 set_cpu_present(bootstrap_processor, true);
387}
388
389
390
391/*
392** inventory.c:do_inventory() hasn't yet been run and thus we
393** don't 'discover' the additional CPUs until later.
394*/
395void __init smp_prepare_cpus(unsigned int max_cpus)
396{
397 int cpu;
398
399 for_each_possible_cpu(cpu)
400 spin_lock_init(&per_cpu(ipi_lock, cpu));
401
402 init_cpu_present(cpumask_of(0));
403
404 parisc_max_cpus = max_cpus;
405 if (!max_cpus)
406 printk(KERN_INFO "SMP mode deactivated.\n");
407}
408
409
410void smp_cpus_done(unsigned int cpu_max)
411{
412 return;
413}
414
415
416int __cpu_up(unsigned int cpu, struct task_struct *tidle)
417{
418 if (cpu != 0 && cpu < parisc_max_cpus)
419 smp_boot_one_cpu(cpu, tidle);
420
421 return cpu_online(cpu) ? 0 : -ENOSYS;
422}
423
424#ifdef CONFIG_PROC_FS
425int __init
426setup_profiling_timer(unsigned int multiplier)
427{
428 return -EINVAL;
429}
430#endif