Commit | Line | Data |
---|---|---|
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 | |
54 | static 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 |
62 | volatile struct task_struct *smp_init_current_idle_task; |
63 | ||
ef017beb | 64 | /* track which CPU is booting */ |
60ffef06 | 65 | static volatile int cpu_now_booting; |
1da177e4 | 66 | |
60ffef06 | 67 | static int parisc_max_cpus = 1; |
1da177e4 | 68 | |
6ad6c424 | 69 | static DEFINE_PER_CPU(spinlock_t, ipi_lock); |
1da177e4 | 70 | |
1da177e4 LT |
71 | enum 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 | */ | |
89 | static void | |
90 | ipi_init(int cpuid) | |
91 | { | |
1da177e4 LT |
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 | */ | |
108 | static void | |
109 | halt_processor(void) | |
110 | { | |
1da177e4 LT |
111 | /* REVISIT : redirect I/O Interrupts to another CPU? */ |
112 | /* REVISIT : does PM *know* this CPU isn't available? */ | |
9bc181d8 | 113 | set_cpu_online(smp_processor_id(), false); |
1da177e4 LT |
114 | local_irq_disable(); |
115 | for (;;) | |
116 | ; | |
1da177e4 LT |
117 | } |
118 | ||
119 | ||
d75f054a | 120 | irqreturn_t __irq_entry |
c7753f18 | 121 | ipi_interrupt(int irq, void *dev_id) |
1da177e4 LT |
122 | { |
123 | int this_cpu = smp_processor_id(); | |
ef017beb | 124 | struct cpuinfo_parisc *p = &per_cpu(cpu_data, this_cpu); |
1da177e4 LT |
125 | unsigned long ops; |
126 | unsigned long flags; | |
127 | ||
1da177e4 | 128 | for (;;) { |
3c97b5e9 KM |
129 | spinlock_t *lock = &per_cpu(ipi_lock, this_cpu); |
130 | spin_lock_irqsave(lock, flags); | |
1da177e4 LT |
131 | ops = p->pending_ipi; |
132 | p->pending_ipi = 0; | |
3c97b5e9 | 133 | spin_unlock_irqrestore(lock, flags); |
1da177e4 LT |
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 | ||
d911aed8 JB |
143 | ops &= ~(1 << which); |
144 | ||
1da177e4 | 145 | switch (which) { |
d911aed8 | 146 | case IPI_NOP: |
5492a0f0 | 147 | smp_debug(100, KERN_DEBUG "CPU%d IPI_NOP\n", this_cpu); |
d911aed8 JB |
148 | break; |
149 | ||
1da177e4 | 150 | case IPI_RESCHEDULE: |
5492a0f0 | 151 | smp_debug(100, KERN_DEBUG "CPU%d IPI_RESCHEDULE\n", this_cpu); |
cd85d551 | 152 | inc_irq_stat(irq_resched_count); |
184748cc | 153 | scheduler_ipi(); |
1da177e4 LT |
154 | break; |
155 | ||
156 | case IPI_CALL_FUNC: | |
5492a0f0 | 157 | smp_debug(100, KERN_DEBUG "CPU%d IPI_CALL_FUNC\n", this_cpu); |
dbcf4787 JA |
158 | generic_smp_call_function_interrupt(); |
159 | break; | |
160 | ||
1da177e4 | 161 | case IPI_CPU_START: |
5492a0f0 | 162 | smp_debug(100, KERN_DEBUG "CPU%d IPI_CPU_START\n", this_cpu); |
1da177e4 LT |
163 | break; |
164 | ||
165 | case IPI_CPU_STOP: | |
5492a0f0 | 166 | smp_debug(100, KERN_DEBUG "CPU%d IPI_CPU_STOP\n", this_cpu); |
1da177e4 | 167 | halt_processor(); |
1da177e4 LT |
168 | break; |
169 | ||
170 | case IPI_CPU_TEST: | |
5492a0f0 | 171 | smp_debug(100, KERN_DEBUG "CPU%d is alive!\n", this_cpu); |
1da177e4 LT |
172 | break; |
173 | ||
174 | default: | |
175 | printk(KERN_CRIT "Unknown IPI num on CPU%d: %lu\n", | |
176 | this_cpu, which); | |
1da177e4 LT |
177 | return IRQ_NONE; |
178 | } /* Switch */ | |
7085689e JB |
179 | /* let in any pending interrupts */ |
180 | local_irq_enable(); | |
181 | local_irq_disable(); | |
1da177e4 LT |
182 | } /* while (ops) */ |
183 | } | |
184 | return IRQ_HANDLED; | |
185 | } | |
186 | ||
187 | ||
188 | static inline void | |
189 | ipi_send(int cpu, enum ipi_message_type op) | |
190 | { | |
ef017beb | 191 | struct cpuinfo_parisc *p = &per_cpu(cpu_data, cpu); |
3c97b5e9 | 192 | spinlock_t *lock = &per_cpu(ipi_lock, cpu); |
1da177e4 LT |
193 | unsigned long flags; |
194 | ||
3c97b5e9 | 195 | spin_lock_irqsave(lock, flags); |
1da177e4 | 196 | p->pending_ipi |= 1 << op; |
ef017beb | 197 | gsc_writel(IPI_IRQ - CPU_IRQ_BASE, p->hpa); |
3c97b5e9 | 198 | spin_unlock_irqrestore(lock, flags); |
1da177e4 LT |
199 | } |
200 | ||
dbcf4787 | 201 | static void |
91887a36 | 202 | send_IPI_mask(const struct cpumask *mask, enum ipi_message_type op) |
dbcf4787 JA |
203 | { |
204 | int cpu; | |
205 | ||
91887a36 | 206 | for_each_cpu(cpu, mask) |
dbcf4787 JA |
207 | ipi_send(cpu, op); |
208 | } | |
1da177e4 LT |
209 | |
210 | static inline void | |
211 | send_IPI_single(int dest_cpu, enum ipi_message_type op) | |
212 | { | |
7f2347a4 | 213 | BUG_ON(dest_cpu == NO_PROC_ID); |
1da177e4 LT |
214 | |
215 | ipi_send(dest_cpu, op); | |
216 | } | |
217 | ||
218 | static inline void | |
219 | send_IPI_allbutself(enum ipi_message_type op) | |
220 | { | |
221 | int i; | |
222 | ||
394e3902 AM |
223 | for_each_online_cpu(i) { |
224 | if (i != smp_processor_id()) | |
1da177e4 LT |
225 | send_IPI_single(i, op); |
226 | } | |
227 | } | |
228 | ||
229 | ||
230 | inline void | |
231 | smp_send_stop(void) { send_IPI_allbutself(IPI_CPU_STOP); } | |
232 | ||
233 | static inline void | |
234 | smp_send_start(void) { send_IPI_allbutself(IPI_CPU_START); } | |
235 | ||
236 | void | |
237 | smp_send_reschedule(int cpu) { send_IPI_single(cpu, IPI_RESCHEDULE); } | |
238 | ||
d911aed8 JB |
239 | void |
240 | smp_send_all_nop(void) | |
241 | { | |
242 | send_IPI_allbutself(IPI_NOP); | |
243 | } | |
244 | ||
91887a36 | 245 | void arch_send_call_function_ipi_mask(const struct cpumask *mask) |
1da177e4 | 246 | { |
dbcf4787 | 247 | send_IPI_mask(mask, IPI_CALL_FUNC); |
1da177e4 LT |
248 | } |
249 | ||
dbcf4787 JA |
250 | void arch_send_call_function_single_ipi(int cpu) |
251 | { | |
528d8eb2 | 252 | send_IPI_single(cpu, IPI_CALL_FUNC); |
dbcf4787 | 253 | } |
1da177e4 | 254 | |
1da177e4 LT |
255 | /* |
256 | * Called by secondaries to update state and initialize CPU registers. | |
257 | */ | |
258 | static void __init | |
259 | smp_cpu_init(int cpunum) | |
260 | { | |
56f335c8 | 261 | extern int init_per_cpu(int); /* arch/parisc/kernel/processor.c */ |
1da177e4 | 262 | extern void init_IRQ(void); /* arch/parisc/kernel/irq.c */ |
56f335c8 | 263 | extern void start_cpu_itimer(void); /* arch/parisc/kernel/time.c */ |
1da177e4 LT |
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. */ | |
7ec6118c | 273 | if (cpu_online(cpunum)) { |
1da177e4 LT |
274 | extern void machine_halt(void); /* arch/parisc.../process.c */ |
275 | ||
276 | printk(KERN_CRIT "CPU#%d already initialized!\n", cpunum); | |
277 | machine_halt(); | |
ec2e0f98 SB |
278 | } |
279 | ||
280 | notify_cpu_starting(cpunum); | |
281 | ||
9bc181d8 | 282 | set_cpu_online(cpunum, true); |
1da177e4 LT |
283 | |
284 | /* Initialise the idle task for this CPU */ | |
285 | atomic_inc(&init_mm.mm_count); | |
286 | current->active_mm = &init_mm; | |
7f2347a4 | 287 | BUG_ON(current->mm); |
1da177e4 LT |
288 | enter_lazy_tlb(&init_mm, current); |
289 | ||
7022672e | 290 | init_IRQ(); /* make sure no IRQs are enabled or pending */ |
56f335c8 | 291 | start_cpu_itimer(); |
1da177e4 LT |
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 | */ | |
299 | void __init smp_callin(void) | |
300 | { | |
301 | int slave_id = cpu_now_booting; | |
1da177e4 LT |
302 | |
303 | smp_cpu_init(slave_id); | |
5bfb5d69 | 304 | preempt_disable(); |
1da177e4 | 305 | |
1da177e4 | 306 | flush_cache_all_local(); /* start with known state */ |
1b2425e3 | 307 | flush_tlb_all_local(NULL); |
1da177e4 LT |
308 | |
309 | local_irq_enable(); /* Interrupts have been off until now */ | |
310 | ||
fad48ad6 | 311 | cpu_startup_entry(CPUHP_ONLINE); |
1da177e4 LT |
312 | |
313 | /* NOTREACHED */ | |
314 | panic("smp_callin() AAAAaaaaahhhh....\n"); | |
315 | } | |
316 | ||
317 | /* | |
318 | * Bring one cpu online. | |
319 | */ | |
60ffef06 | 320 | int smp_boot_one_cpu(int cpuid, struct task_struct *idle) |
1da177e4 | 321 | { |
ef017beb | 322 | const struct cpuinfo_parisc *p = &per_cpu(cpu_data, cpuid); |
1da177e4 LT |
323 | long timeout; |
324 | ||
40f1f0de | 325 | task_thread_info(idle)->cpu = cpuid; |
1da177e4 LT |
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 | ||
ef017beb | 339 | printk(KERN_INFO "Releasing cpu %d now, hpa=%lx\n", cpuid, p->hpa); |
1da177e4 LT |
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 | */ | |
ef017beb | 350 | gsc_writel(TIMER_IRQ - CPU_IRQ_BASE, p->hpa); |
1da177e4 LT |
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 | } | |
1da177e4 LT |
368 | printk(KERN_CRIT "SMP: CPU:%d is stuck.\n", cpuid); |
369 | return -1; | |
370 | ||
371 | alive: | |
372 | /* Remember the Slave data */ | |
5492a0f0 | 373 | smp_debug(100, KERN_DEBUG "SMP: CPU:%d came alive after %ld _us\n", |
1da177e4 | 374 | cpuid, timeout * 100); |
1da177e4 LT |
375 | return 0; |
376 | } | |
377 | ||
ef017beb | 378 | void __init smp_prepare_boot_cpu(void) |
1da177e4 | 379 | { |
ef017beb | 380 | int bootstrap_processor = per_cpu(cpu_data, 0).cpuid; |
1da177e4 | 381 | |
1da177e4 | 382 | /* Setup BSP mappings */ |
ef017beb | 383 | printk(KERN_INFO "SMP: bootstrap CPU ID is %d\n", bootstrap_processor); |
1da177e4 | 384 | |
9bc181d8 RR |
385 | set_cpu_online(bootstrap_processor, true); |
386 | set_cpu_present(bootstrap_processor, true); | |
1da177e4 LT |
387 | } |
388 | ||
389 | ||
390 | ||
391 | /* | |
392 | ** inventory.c:do_inventory() hasn't yet been run and thus we | |
7022672e | 393 | ** don't 'discover' the additional CPUs until later. |
1da177e4 LT |
394 | */ |
395 | void __init smp_prepare_cpus(unsigned int max_cpus) | |
396 | { | |
6ad6c424 TG |
397 | int cpu; |
398 | ||
399 | for_each_possible_cpu(cpu) | |
400 | spin_lock_init(&per_cpu(ipi_lock, cpu)); | |
401 | ||
9bc181d8 | 402 | init_cpu_present(cpumask_of(0)); |
1da177e4 LT |
403 | |
404 | parisc_max_cpus = max_cpus; | |
405 | if (!max_cpus) | |
406 | printk(KERN_INFO "SMP mode deactivated.\n"); | |
407 | } | |
408 | ||
409 | ||
410 | void smp_cpus_done(unsigned int cpu_max) | |
411 | { | |
412 | return; | |
413 | } | |
414 | ||
415 | ||
60ffef06 | 416 | int __cpu_up(unsigned int cpu, struct task_struct *tidle) |
1da177e4 LT |
417 | { |
418 | if (cpu != 0 && cpu < parisc_max_cpus) | |
9a134723 | 419 | smp_boot_one_cpu(cpu, tidle); |
1da177e4 LT |
420 | |
421 | return cpu_online(cpu) ? 0 : -ENOSYS; | |
422 | } | |
423 | ||
1da177e4 LT |
424 | #ifdef CONFIG_PROC_FS |
425 | int __init | |
426 | setup_profiling_timer(unsigned int multiplier) | |
427 | { | |
428 | return -EINVAL; | |
429 | } | |
430 | #endif |