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authorPaul Mackerras <paulus@samba.org>2005-10-10 08:03:41 -0400
committerPaul Mackerras <paulus@samba.org>2005-10-10 08:03:41 -0400
commit69a80d3f69d0b2d7fae5a73c6e034d402d434d8a (patch)
treedd66f34510eae791a04c8dd77ce77a223b2f46d6 /arch/powerpc/platforms/pseries/smp.c
parentab1f9dac6eea25ee59e4c8e1cf0b7476afbbfe07 (diff)
powerpc: move pSeries files to arch/powerpc/platforms/pseries
Signed-off-by: Paul Mackerras <paulus@samba.org>
Diffstat (limited to 'arch/powerpc/platforms/pseries/smp.c')
-rw-r--r--arch/powerpc/platforms/pseries/smp.c471
1 files changed, 471 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/pseries/smp.c b/arch/powerpc/platforms/pseries/smp.c
new file mode 100644
index 000000000000..ae1bd270f308
--- /dev/null
+++ b/arch/powerpc/platforms/pseries/smp.c
@@ -0,0 +1,471 @@
1/*
2 * SMP support for pSeries machines.
3 *
4 * Dave Engebretsen, Peter Bergner, and
5 * Mike Corrigan {engebret|bergner|mikec}@us.ibm.com
6 *
7 * Plus various changes from other IBM teams...
8 *
9 * This program is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU General Public License
11 * as published by the Free Software Foundation; either version
12 * 2 of the License, or (at your option) any later version.
13 */
14
15#undef DEBUG
16
17#include <linux/config.h>
18#include <linux/kernel.h>
19#include <linux/module.h>
20#include <linux/sched.h>
21#include <linux/smp.h>
22#include <linux/interrupt.h>
23#include <linux/delay.h>
24#include <linux/init.h>
25#include <linux/spinlock.h>
26#include <linux/cache.h>
27#include <linux/err.h>
28#include <linux/sysdev.h>
29#include <linux/cpu.h>
30
31#include <asm/ptrace.h>
32#include <asm/atomic.h>
33#include <asm/irq.h>
34#include <asm/page.h>
35#include <asm/pgtable.h>
36#include <asm/io.h>
37#include <asm/prom.h>
38#include <asm/smp.h>
39#include <asm/paca.h>
40#include <asm/time.h>
41#include <asm/machdep.h>
42#include <asm/xics.h>
43#include <asm/cputable.h>
44#include <asm/firmware.h>
45#include <asm/system.h>
46#include <asm/rtas.h>
47#include <asm/plpar_wrappers.h>
48#include <asm/pSeries_reconfig.h>
49#include <asm/mpic.h>
50
51#ifdef DEBUG
52#define DBG(fmt...) udbg_printf(fmt)
53#else
54#define DBG(fmt...)
55#endif
56
57/*
58 * The primary thread of each non-boot processor is recorded here before
59 * smp init.
60 */
61static cpumask_t of_spin_map;
62
63extern void pSeries_secondary_smp_init(unsigned long);
64
65#ifdef CONFIG_HOTPLUG_CPU
66
67/* Get state of physical CPU.
68 * Return codes:
69 * 0 - The processor is in the RTAS stopped state
70 * 1 - stop-self is in progress
71 * 2 - The processor is not in the RTAS stopped state
72 * -1 - Hardware Error
73 * -2 - Hardware Busy, Try again later.
74 */
75static int query_cpu_stopped(unsigned int pcpu)
76{
77 int cpu_status;
78 int status, qcss_tok;
79
80 qcss_tok = rtas_token("query-cpu-stopped-state");
81 if (qcss_tok == RTAS_UNKNOWN_SERVICE)
82 return -1;
83 status = rtas_call(qcss_tok, 1, 2, &cpu_status, pcpu);
84 if (status != 0) {
85 printk(KERN_ERR
86 "RTAS query-cpu-stopped-state failed: %i\n", status);
87 return status;
88 }
89
90 return cpu_status;
91}
92
93int pSeries_cpu_disable(void)
94{
95 int cpu = smp_processor_id();
96
97 cpu_clear(cpu, cpu_online_map);
98 systemcfg->processorCount--;
99
100 /*fix boot_cpuid here*/
101 if (cpu == boot_cpuid)
102 boot_cpuid = any_online_cpu(cpu_online_map);
103
104 /* FIXME: abstract this to not be platform specific later on */
105 xics_migrate_irqs_away();
106 return 0;
107}
108
109void pSeries_cpu_die(unsigned int cpu)
110{
111 int tries;
112 int cpu_status;
113 unsigned int pcpu = get_hard_smp_processor_id(cpu);
114
115 for (tries = 0; tries < 25; tries++) {
116 cpu_status = query_cpu_stopped(pcpu);
117 if (cpu_status == 0 || cpu_status == -1)
118 break;
119 msleep(200);
120 }
121 if (cpu_status != 0) {
122 printk("Querying DEAD? cpu %i (%i) shows %i\n",
123 cpu, pcpu, cpu_status);
124 }
125
126 /* Isolation and deallocation are definatly done by
127 * drslot_chrp_cpu. If they were not they would be
128 * done here. Change isolate state to Isolate and
129 * change allocation-state to Unusable.
130 */
131 paca[cpu].cpu_start = 0;
132}
133
134/*
135 * Update cpu_present_map and paca(s) for a new cpu node. The wrinkle
136 * here is that a cpu device node may represent up to two logical cpus
137 * in the SMT case. We must honor the assumption in other code that
138 * the logical ids for sibling SMT threads x and y are adjacent, such
139 * that x^1 == y and y^1 == x.
140 */
141static int pSeries_add_processor(struct device_node *np)
142{
143 unsigned int cpu;
144 cpumask_t candidate_map, tmp = CPU_MASK_NONE;
145 int err = -ENOSPC, len, nthreads, i;
146 u32 *intserv;
147
148 intserv = (u32 *)get_property(np, "ibm,ppc-interrupt-server#s", &len);
149 if (!intserv)
150 return 0;
151
152 nthreads = len / sizeof(u32);
153 for (i = 0; i < nthreads; i++)
154 cpu_set(i, tmp);
155
156 lock_cpu_hotplug();
157
158 BUG_ON(!cpus_subset(cpu_present_map, cpu_possible_map));
159
160 /* Get a bitmap of unoccupied slots. */
161 cpus_xor(candidate_map, cpu_possible_map, cpu_present_map);
162 if (cpus_empty(candidate_map)) {
163 /* If we get here, it most likely means that NR_CPUS is
164 * less than the partition's max processors setting.
165 */
166 printk(KERN_ERR "Cannot add cpu %s; this system configuration"
167 " supports %d logical cpus.\n", np->full_name,
168 cpus_weight(cpu_possible_map));
169 goto out_unlock;
170 }
171
172 while (!cpus_empty(tmp))
173 if (cpus_subset(tmp, candidate_map))
174 /* Found a range where we can insert the new cpu(s) */
175 break;
176 else
177 cpus_shift_left(tmp, tmp, nthreads);
178
179 if (cpus_empty(tmp)) {
180 printk(KERN_ERR "Unable to find space in cpu_present_map for"
181 " processor %s with %d thread(s)\n", np->name,
182 nthreads);
183 goto out_unlock;
184 }
185
186 for_each_cpu_mask(cpu, tmp) {
187 BUG_ON(cpu_isset(cpu, cpu_present_map));
188 cpu_set(cpu, cpu_present_map);
189 set_hard_smp_processor_id(cpu, *intserv++);
190 }
191 err = 0;
192out_unlock:
193 unlock_cpu_hotplug();
194 return err;
195}
196
197/*
198 * Update the present map for a cpu node which is going away, and set
199 * the hard id in the paca(s) to -1 to be consistent with boot time
200 * convention for non-present cpus.
201 */
202static void pSeries_remove_processor(struct device_node *np)
203{
204 unsigned int cpu;
205 int len, nthreads, i;
206 u32 *intserv;
207
208 intserv = (u32 *)get_property(np, "ibm,ppc-interrupt-server#s", &len);
209 if (!intserv)
210 return;
211
212 nthreads = len / sizeof(u32);
213
214 lock_cpu_hotplug();
215 for (i = 0; i < nthreads; i++) {
216 for_each_present_cpu(cpu) {
217 if (get_hard_smp_processor_id(cpu) != intserv[i])
218 continue;
219 BUG_ON(cpu_online(cpu));
220 cpu_clear(cpu, cpu_present_map);
221 set_hard_smp_processor_id(cpu, -1);
222 break;
223 }
224 if (cpu == NR_CPUS)
225 printk(KERN_WARNING "Could not find cpu to remove "
226 "with physical id 0x%x\n", intserv[i]);
227 }
228 unlock_cpu_hotplug();
229}
230
231static int pSeries_smp_notifier(struct notifier_block *nb, unsigned long action, void *node)
232{
233 int err = NOTIFY_OK;
234
235 switch (action) {
236 case PSERIES_RECONFIG_ADD:
237 if (pSeries_add_processor(node))
238 err = NOTIFY_BAD;
239 break;
240 case PSERIES_RECONFIG_REMOVE:
241 pSeries_remove_processor(node);
242 break;
243 default:
244 err = NOTIFY_DONE;
245 break;
246 }
247 return err;
248}
249
250static struct notifier_block pSeries_smp_nb = {
251 .notifier_call = pSeries_smp_notifier,
252};
253
254#endif /* CONFIG_HOTPLUG_CPU */
255
256/**
257 * smp_startup_cpu() - start the given cpu
258 *
259 * At boot time, there is nothing to do for primary threads which were
260 * started from Open Firmware. For anything else, call RTAS with the
261 * appropriate start location.
262 *
263 * Returns:
264 * 0 - failure
265 * 1 - success
266 */
267static inline int __devinit smp_startup_cpu(unsigned int lcpu)
268{
269 int status;
270 unsigned long start_here = __pa((u32)*((unsigned long *)
271 pSeries_secondary_smp_init));
272 unsigned int pcpu;
273 int start_cpu;
274
275 if (cpu_isset(lcpu, of_spin_map))
276 /* Already started by OF and sitting in spin loop */
277 return 1;
278
279 pcpu = get_hard_smp_processor_id(lcpu);
280
281 /* Fixup atomic count: it exited inside IRQ handler. */
282 paca[lcpu].__current->thread_info->preempt_count = 0;
283
284 /*
285 * If the RTAS start-cpu token does not exist then presume the
286 * cpu is already spinning.
287 */
288 start_cpu = rtas_token("start-cpu");
289 if (start_cpu == RTAS_UNKNOWN_SERVICE)
290 return 1;
291
292 status = rtas_call(start_cpu, 3, 1, NULL, pcpu, start_here, lcpu);
293 if (status != 0) {
294 printk(KERN_ERR "start-cpu failed: %i\n", status);
295 return 0;
296 }
297
298 return 1;
299}
300
301#ifdef CONFIG_XICS
302static inline void smp_xics_do_message(int cpu, int msg)
303{
304 set_bit(msg, &xics_ipi_message[cpu].value);
305 mb();
306 xics_cause_IPI(cpu);
307}
308
309static void smp_xics_message_pass(int target, int msg)
310{
311 unsigned int i;
312
313 if (target < NR_CPUS) {
314 smp_xics_do_message(target, msg);
315 } else {
316 for_each_online_cpu(i) {
317 if (target == MSG_ALL_BUT_SELF
318 && i == smp_processor_id())
319 continue;
320 smp_xics_do_message(i, msg);
321 }
322 }
323}
324
325static int __init smp_xics_probe(void)
326{
327 xics_request_IPIs();
328
329 return cpus_weight(cpu_possible_map);
330}
331
332static void __devinit smp_xics_setup_cpu(int cpu)
333{
334 if (cpu != boot_cpuid)
335 xics_setup_cpu();
336
337 if (firmware_has_feature(FW_FEATURE_SPLPAR))
338 vpa_init(cpu);
339
340 cpu_clear(cpu, of_spin_map);
341
342}
343#endif /* CONFIG_XICS */
344
345static DEFINE_SPINLOCK(timebase_lock);
346static unsigned long timebase = 0;
347
348static void __devinit pSeries_give_timebase(void)
349{
350 spin_lock(&timebase_lock);
351 rtas_call(rtas_token("freeze-time-base"), 0, 1, NULL);
352 timebase = get_tb();
353 spin_unlock(&timebase_lock);
354
355 while (timebase)
356 barrier();
357 rtas_call(rtas_token("thaw-time-base"), 0, 1, NULL);
358}
359
360static void __devinit pSeries_take_timebase(void)
361{
362 while (!timebase)
363 barrier();
364 spin_lock(&timebase_lock);
365 set_tb(timebase >> 32, timebase & 0xffffffff);
366 timebase = 0;
367 spin_unlock(&timebase_lock);
368}
369
370static void __devinit smp_pSeries_kick_cpu(int nr)
371{
372 BUG_ON(nr < 0 || nr >= NR_CPUS);
373
374 if (!smp_startup_cpu(nr))
375 return;
376
377 /*
378 * The processor is currently spinning, waiting for the
379 * cpu_start field to become non-zero After we set cpu_start,
380 * the processor will continue on to secondary_start
381 */
382 paca[nr].cpu_start = 1;
383}
384
385static int smp_pSeries_cpu_bootable(unsigned int nr)
386{
387 /* Special case - we inhibit secondary thread startup
388 * during boot if the user requests it. Odd-numbered
389 * cpus are assumed to be secondary threads.
390 */
391 if (system_state < SYSTEM_RUNNING &&
392 cpu_has_feature(CPU_FTR_SMT) &&
393 !smt_enabled_at_boot && nr % 2 != 0)
394 return 0;
395
396 return 1;
397}
398#ifdef CONFIG_MPIC
399static struct smp_ops_t pSeries_mpic_smp_ops = {
400 .message_pass = smp_mpic_message_pass,
401 .probe = smp_mpic_probe,
402 .kick_cpu = smp_pSeries_kick_cpu,
403 .setup_cpu = smp_mpic_setup_cpu,
404};
405#endif
406#ifdef CONFIG_XICS
407static struct smp_ops_t pSeries_xics_smp_ops = {
408 .message_pass = smp_xics_message_pass,
409 .probe = smp_xics_probe,
410 .kick_cpu = smp_pSeries_kick_cpu,
411 .setup_cpu = smp_xics_setup_cpu,
412 .cpu_bootable = smp_pSeries_cpu_bootable,
413};
414#endif
415
416/* This is called very early */
417void __init smp_init_pSeries(void)
418{
419 int i;
420
421 DBG(" -> smp_init_pSeries()\n");
422
423 switch (ppc64_interrupt_controller) {
424#ifdef CONFIG_MPIC
425 case IC_OPEN_PIC:
426 smp_ops = &pSeries_mpic_smp_ops;
427 break;
428#endif
429#ifdef CONFIG_XICS
430 case IC_PPC_XIC:
431 smp_ops = &pSeries_xics_smp_ops;
432 break;
433#endif
434 default:
435 panic("Invalid interrupt controller");
436 }
437
438#ifdef CONFIG_HOTPLUG_CPU
439 smp_ops->cpu_disable = pSeries_cpu_disable;
440 smp_ops->cpu_die = pSeries_cpu_die;
441
442 /* Processors can be added/removed only on LPAR */
443 if (systemcfg->platform == PLATFORM_PSERIES_LPAR)
444 pSeries_reconfig_notifier_register(&pSeries_smp_nb);
445#endif
446
447 /* Mark threads which are still spinning in hold loops. */
448 if (cpu_has_feature(CPU_FTR_SMT)) {
449 for_each_present_cpu(i) {
450 if (i % 2 == 0)
451 /*
452 * Even-numbered logical cpus correspond to
453 * primary threads.
454 */
455 cpu_set(i, of_spin_map);
456 }
457 } else {
458 of_spin_map = cpu_present_map;
459 }
460
461 cpu_clear(boot_cpuid, of_spin_map);
462
463 /* Non-lpar has additional take/give timebase */
464 if (rtas_token("freeze-time-base") != RTAS_UNKNOWN_SERVICE) {
465 smp_ops->give_timebase = pSeries_give_timebase;
466 smp_ops->take_timebase = pSeries_take_timebase;
467 }
468
469 DBG(" <- smp_init_pSeries()\n");
470}
471