ia64/linux-2.6.18-xen.hg

view drivers/char/mmtimer.c @ 893:f994bfe9b93b

linux/blktap2: reduce TLB flush scope

c/s 885 added very coarse TLB flushing. Since these flushes always
follow single page updates, single page flushes (when available) are
sufficient.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
author Keir Fraser <keir.fraser@citrix.com>
date Thu Jun 04 10:32:57 2009 +0100 (2009-06-04)
parents 831230e53067
children
line source
1 /*
2 * Timer device implementation for SGI SN platforms.
3 *
4 * This file is subject to the terms and conditions of the GNU General Public
5 * License. See the file "COPYING" in the main directory of this archive
6 * for more details.
7 *
8 * Copyright (c) 2001-2006 Silicon Graphics, Inc. All rights reserved.
9 *
10 * This driver exports an API that should be supportable by any HPET or IA-PC
11 * multimedia timer. The code below is currently specific to the SGI Altix
12 * SHub RTC, however.
13 *
14 * 11/01/01 - jbarnes - initial revision
15 * 9/10/04 - Christoph Lameter - remove interrupt support for kernel inclusion
16 * 10/1/04 - Christoph Lameter - provide posix clock CLOCK_SGI_CYCLE
17 * 10/13/04 - Christoph Lameter, Dimitri Sivanich - provide timer interrupt
18 * support via the posix timer interface
19 */
21 #include <linux/types.h>
22 #include <linux/kernel.h>
23 #include <linux/ioctl.h>
24 #include <linux/module.h>
25 #include <linux/init.h>
26 #include <linux/errno.h>
27 #include <linux/mm.h>
28 #include <linux/mmtimer.h>
29 #include <linux/miscdevice.h>
30 #include <linux/posix-timers.h>
31 #include <linux/interrupt.h>
33 #include <asm/uaccess.h>
34 #include <asm/sn/addrs.h>
35 #include <asm/sn/intr.h>
36 #include <asm/sn/shub_mmr.h>
37 #include <asm/sn/nodepda.h>
38 #include <asm/sn/shubio.h>
40 MODULE_AUTHOR("Jesse Barnes <jbarnes@sgi.com>");
41 MODULE_DESCRIPTION("SGI Altix RTC Timer");
42 MODULE_LICENSE("GPL");
44 /* name of the device, usually in /dev */
45 #define MMTIMER_NAME "mmtimer"
46 #define MMTIMER_DESC "SGI Altix RTC Timer"
47 #define MMTIMER_VERSION "2.1"
49 #define RTC_BITS 55 /* 55 bits for this implementation */
51 extern unsigned long sn_rtc_cycles_per_second;
53 #define RTC_COUNTER_ADDR ((long *)LOCAL_MMR_ADDR(SH_RTC))
55 #define rtc_time() (*RTC_COUNTER_ADDR)
57 static int mmtimer_ioctl(struct inode *inode, struct file *file,
58 unsigned int cmd, unsigned long arg);
59 static int mmtimer_mmap(struct file *file, struct vm_area_struct *vma);
61 /*
62 * Period in femtoseconds (10^-15 s)
63 */
64 static unsigned long mmtimer_femtoperiod = 0;
66 static const struct file_operations mmtimer_fops = {
67 .owner = THIS_MODULE,
68 .mmap = mmtimer_mmap,
69 .ioctl = mmtimer_ioctl,
70 };
72 /*
73 * We only have comparison registers RTC1-4 currently available per
74 * node. RTC0 is used by SAL.
75 */
76 #define NUM_COMPARATORS 3
77 /* Check for an RTC interrupt pending */
78 static int inline mmtimer_int_pending(int comparator)
79 {
80 if (HUB_L((unsigned long *)LOCAL_MMR_ADDR(SH_EVENT_OCCURRED)) &
81 SH_EVENT_OCCURRED_RTC1_INT_MASK << comparator)
82 return 1;
83 else
84 return 0;
85 }
86 /* Clear the RTC interrupt pending bit */
87 static void inline mmtimer_clr_int_pending(int comparator)
88 {
89 HUB_S((u64 *)LOCAL_MMR_ADDR(SH_EVENT_OCCURRED_ALIAS),
90 SH_EVENT_OCCURRED_RTC1_INT_MASK << comparator);
91 }
93 /* Setup timer on comparator RTC1 */
94 static void inline mmtimer_setup_int_0(u64 expires)
95 {
96 u64 val;
98 /* Disable interrupt */
99 HUB_S((u64 *)LOCAL_MMR_ADDR(SH_RTC1_INT_ENABLE), 0UL);
101 /* Initialize comparator value */
102 HUB_S((u64 *)LOCAL_MMR_ADDR(SH_INT_CMPB), -1L);
104 /* Clear pending bit */
105 mmtimer_clr_int_pending(0);
107 val = ((u64)SGI_MMTIMER_VECTOR << SH_RTC1_INT_CONFIG_IDX_SHFT) |
108 ((u64)cpu_physical_id(smp_processor_id()) <<
109 SH_RTC1_INT_CONFIG_PID_SHFT);
111 /* Set configuration */
112 HUB_S((u64 *)LOCAL_MMR_ADDR(SH_RTC1_INT_CONFIG), val);
114 /* Enable RTC interrupts */
115 HUB_S((u64 *)LOCAL_MMR_ADDR(SH_RTC1_INT_ENABLE), 1UL);
117 /* Initialize comparator value */
118 HUB_S((u64 *)LOCAL_MMR_ADDR(SH_INT_CMPB), expires);
121 }
123 /* Setup timer on comparator RTC2 */
124 static void inline mmtimer_setup_int_1(u64 expires)
125 {
126 u64 val;
128 HUB_S((u64 *)LOCAL_MMR_ADDR(SH_RTC2_INT_ENABLE), 0UL);
130 HUB_S((u64 *)LOCAL_MMR_ADDR(SH_INT_CMPC), -1L);
132 mmtimer_clr_int_pending(1);
134 val = ((u64)SGI_MMTIMER_VECTOR << SH_RTC2_INT_CONFIG_IDX_SHFT) |
135 ((u64)cpu_physical_id(smp_processor_id()) <<
136 SH_RTC2_INT_CONFIG_PID_SHFT);
138 HUB_S((u64 *)LOCAL_MMR_ADDR(SH_RTC2_INT_CONFIG), val);
140 HUB_S((u64 *)LOCAL_MMR_ADDR(SH_RTC2_INT_ENABLE), 1UL);
142 HUB_S((u64 *)LOCAL_MMR_ADDR(SH_INT_CMPC), expires);
143 }
145 /* Setup timer on comparator RTC3 */
146 static void inline mmtimer_setup_int_2(u64 expires)
147 {
148 u64 val;
150 HUB_S((u64 *)LOCAL_MMR_ADDR(SH_RTC3_INT_ENABLE), 0UL);
152 HUB_S((u64 *)LOCAL_MMR_ADDR(SH_INT_CMPD), -1L);
154 mmtimer_clr_int_pending(2);
156 val = ((u64)SGI_MMTIMER_VECTOR << SH_RTC3_INT_CONFIG_IDX_SHFT) |
157 ((u64)cpu_physical_id(smp_processor_id()) <<
158 SH_RTC3_INT_CONFIG_PID_SHFT);
160 HUB_S((u64 *)LOCAL_MMR_ADDR(SH_RTC3_INT_CONFIG), val);
162 HUB_S((u64 *)LOCAL_MMR_ADDR(SH_RTC3_INT_ENABLE), 1UL);
164 HUB_S((u64 *)LOCAL_MMR_ADDR(SH_INT_CMPD), expires);
165 }
167 /*
168 * This function must be called with interrupts disabled and preemption off
169 * in order to insure that the setup succeeds in a deterministic time frame.
170 * It will check if the interrupt setup succeeded.
171 */
172 static int inline mmtimer_setup(int comparator, unsigned long expires)
173 {
175 switch (comparator) {
176 case 0:
177 mmtimer_setup_int_0(expires);
178 break;
179 case 1:
180 mmtimer_setup_int_1(expires);
181 break;
182 case 2:
183 mmtimer_setup_int_2(expires);
184 break;
185 }
186 /* We might've missed our expiration time */
187 if (rtc_time() < expires)
188 return 1;
190 /*
191 * If an interrupt is already pending then its okay
192 * if not then we failed
193 */
194 return mmtimer_int_pending(comparator);
195 }
197 static int inline mmtimer_disable_int(long nasid, int comparator)
198 {
199 switch (comparator) {
200 case 0:
201 nasid == -1 ? HUB_S((u64 *)LOCAL_MMR_ADDR(SH_RTC1_INT_ENABLE),
202 0UL) : REMOTE_HUB_S(nasid, SH_RTC1_INT_ENABLE, 0UL);
203 break;
204 case 1:
205 nasid == -1 ? HUB_S((u64 *)LOCAL_MMR_ADDR(SH_RTC2_INT_ENABLE),
206 0UL) : REMOTE_HUB_S(nasid, SH_RTC2_INT_ENABLE, 0UL);
207 break;
208 case 2:
209 nasid == -1 ? HUB_S((u64 *)LOCAL_MMR_ADDR(SH_RTC3_INT_ENABLE),
210 0UL) : REMOTE_HUB_S(nasid, SH_RTC3_INT_ENABLE, 0UL);
211 break;
212 default:
213 return -EFAULT;
214 }
215 return 0;
216 }
218 #define TIMER_OFF 0xbadcabLL
220 /* There is one of these for each comparator */
221 typedef struct mmtimer {
222 spinlock_t lock ____cacheline_aligned;
223 struct k_itimer *timer;
224 int i;
225 int cpu;
226 struct tasklet_struct tasklet;
227 } mmtimer_t;
229 static mmtimer_t ** timers;
231 /**
232 * mmtimer_ioctl - ioctl interface for /dev/mmtimer
233 * @inode: inode of the device
234 * @file: file structure for the device
235 * @cmd: command to execute
236 * @arg: optional argument to command
237 *
238 * Executes the command specified by @cmd. Returns 0 for success, < 0 for
239 * failure.
240 *
241 * Valid commands:
242 *
243 * %MMTIMER_GETOFFSET - Should return the offset (relative to the start
244 * of the page where the registers are mapped) for the counter in question.
245 *
246 * %MMTIMER_GETRES - Returns the resolution of the clock in femto (10^-15)
247 * seconds
248 *
249 * %MMTIMER_GETFREQ - Copies the frequency of the clock in Hz to the address
250 * specified by @arg
251 *
252 * %MMTIMER_GETBITS - Returns the number of bits in the clock's counter
253 *
254 * %MMTIMER_MMAPAVAIL - Returns 1 if the registers can be mmap'd into userspace
255 *
256 * %MMTIMER_GETCOUNTER - Gets the current value in the counter and places it
257 * in the address specified by @arg.
258 */
259 static int mmtimer_ioctl(struct inode *inode, struct file *file,
260 unsigned int cmd, unsigned long arg)
261 {
262 int ret = 0;
264 switch (cmd) {
265 case MMTIMER_GETOFFSET: /* offset of the counter */
266 /*
267 * SN RTC registers are on their own 64k page
268 */
269 if(PAGE_SIZE <= (1 << 16))
270 ret = (((long)RTC_COUNTER_ADDR) & (PAGE_SIZE-1)) / 8;
271 else
272 ret = -ENOSYS;
273 break;
275 case MMTIMER_GETRES: /* resolution of the clock in 10^-15 s */
276 if(copy_to_user((unsigned long __user *)arg,
277 &mmtimer_femtoperiod, sizeof(unsigned long)))
278 return -EFAULT;
279 break;
281 case MMTIMER_GETFREQ: /* frequency in Hz */
282 if(copy_to_user((unsigned long __user *)arg,
283 &sn_rtc_cycles_per_second,
284 sizeof(unsigned long)))
285 return -EFAULT;
286 ret = 0;
287 break;
289 case MMTIMER_GETBITS: /* number of bits in the clock */
290 ret = RTC_BITS;
291 break;
293 case MMTIMER_MMAPAVAIL: /* can we mmap the clock into userspace? */
294 ret = (PAGE_SIZE <= (1 << 16)) ? 1 : 0;
295 break;
297 case MMTIMER_GETCOUNTER:
298 if(copy_to_user((unsigned long __user *)arg,
299 RTC_COUNTER_ADDR, sizeof(unsigned long)))
300 return -EFAULT;
301 break;
302 default:
303 ret = -ENOSYS;
304 break;
305 }
307 return ret;
308 }
310 /**
311 * mmtimer_mmap - maps the clock's registers into userspace
312 * @file: file structure for the device
313 * @vma: VMA to map the registers into
314 *
315 * Calls remap_pfn_range() to map the clock's registers into
316 * the calling process' address space.
317 */
318 static int mmtimer_mmap(struct file *file, struct vm_area_struct *vma)
319 {
320 unsigned long mmtimer_addr;
322 if (vma->vm_end - vma->vm_start != PAGE_SIZE)
323 return -EINVAL;
325 if (vma->vm_flags & VM_WRITE)
326 return -EPERM;
328 if (PAGE_SIZE > (1 << 16))
329 return -ENOSYS;
331 vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
333 mmtimer_addr = __pa(RTC_COUNTER_ADDR);
334 mmtimer_addr &= ~(PAGE_SIZE - 1);
335 mmtimer_addr &= 0xfffffffffffffffUL;
337 if (remap_pfn_range(vma, vma->vm_start, mmtimer_addr >> PAGE_SHIFT,
338 PAGE_SIZE, vma->vm_page_prot)) {
339 printk(KERN_ERR "remap_pfn_range failed in mmtimer.c\n");
340 return -EAGAIN;
341 }
343 return 0;
344 }
346 static struct miscdevice mmtimer_miscdev = {
347 SGI_MMTIMER,
348 MMTIMER_NAME,
349 &mmtimer_fops
350 };
352 static struct timespec sgi_clock_offset;
353 static int sgi_clock_period;
355 /*
356 * Posix Timer Interface
357 */
359 static struct timespec sgi_clock_offset;
360 static int sgi_clock_period;
362 static int sgi_clock_get(clockid_t clockid, struct timespec *tp)
363 {
364 u64 nsec;
366 nsec = rtc_time() * sgi_clock_period
367 + sgi_clock_offset.tv_nsec;
368 tp->tv_sec = div_long_long_rem(nsec, NSEC_PER_SEC, &tp->tv_nsec)
369 + sgi_clock_offset.tv_sec;
370 return 0;
371 };
373 static int sgi_clock_set(clockid_t clockid, struct timespec *tp)
374 {
376 u64 nsec;
377 u64 rem;
379 nsec = rtc_time() * sgi_clock_period;
381 sgi_clock_offset.tv_sec = tp->tv_sec - div_long_long_rem(nsec, NSEC_PER_SEC, &rem);
383 if (rem <= tp->tv_nsec)
384 sgi_clock_offset.tv_nsec = tp->tv_sec - rem;
385 else {
386 sgi_clock_offset.tv_nsec = tp->tv_sec + NSEC_PER_SEC - rem;
387 sgi_clock_offset.tv_sec--;
388 }
389 return 0;
390 }
392 /*
393 * Schedule the next periodic interrupt. This function will attempt
394 * to schedule a periodic interrupt later if necessary. If the scheduling
395 * of an interrupt fails then the time to skip is lengthened
396 * exponentially in order to ensure that the next interrupt
397 * can be properly scheduled..
398 */
399 static int inline reschedule_periodic_timer(mmtimer_t *x)
400 {
401 int n;
402 struct k_itimer *t = x->timer;
404 t->it.mmtimer.clock = x->i;
405 t->it_overrun--;
407 n = 0;
408 do {
410 t->it.mmtimer.expires += t->it.mmtimer.incr << n;
411 t->it_overrun += 1 << n;
412 n++;
413 if (n > 20)
414 return 1;
416 } while (!mmtimer_setup(x->i, t->it.mmtimer.expires));
418 return 0;
419 }
421 /**
422 * mmtimer_interrupt - timer interrupt handler
423 * @irq: irq received
424 * @dev_id: device the irq came from
425 * @regs: register state upon receipt of the interrupt
426 *
427 * Called when one of the comarators matches the counter, This
428 * routine will send signals to processes that have requested
429 * them.
430 *
431 * This interrupt is run in an interrupt context
432 * by the SHUB. It is therefore safe to locally access SHub
433 * registers.
434 */
435 static irqreturn_t
436 mmtimer_interrupt(int irq, void *dev_id, struct pt_regs *regs)
437 {
438 int i;
439 unsigned long expires = 0;
440 int result = IRQ_NONE;
441 unsigned indx = cpu_to_node(smp_processor_id());
443 /*
444 * Do this once for each comparison register
445 */
446 for (i = 0; i < NUM_COMPARATORS; i++) {
447 mmtimer_t *base = timers[indx] + i;
448 /* Make sure this doesn't get reused before tasklet_sched */
449 spin_lock(&base->lock);
450 if (base->cpu == smp_processor_id()) {
451 if (base->timer)
452 expires = base->timer->it.mmtimer.expires;
453 /* expires test won't work with shared irqs */
454 if ((mmtimer_int_pending(i) > 0) ||
455 (expires && (expires < rtc_time()))) {
456 mmtimer_clr_int_pending(i);
457 tasklet_schedule(&base->tasklet);
458 result = IRQ_HANDLED;
459 }
460 }
461 spin_unlock(&base->lock);
462 expires = 0;
463 }
464 return result;
465 }
467 void mmtimer_tasklet(unsigned long data) {
468 mmtimer_t *x = (mmtimer_t *)data;
469 struct k_itimer *t = x->timer;
470 unsigned long flags;
472 if (t == NULL)
473 return;
475 /* Send signal and deal with periodic signals */
476 spin_lock_irqsave(&t->it_lock, flags);
477 spin_lock(&x->lock);
478 /* If timer was deleted between interrupt and here, leave */
479 if (t != x->timer)
480 goto out;
481 t->it_overrun = 0;
483 if (posix_timer_event(t, 0) != 0) {
485 // printk(KERN_WARNING "mmtimer: cannot deliver signal.\n");
487 t->it_overrun++;
488 }
489 if(t->it.mmtimer.incr) {
490 /* Periodic timer */
491 if (reschedule_periodic_timer(x)) {
492 printk(KERN_WARNING "mmtimer: unable to reschedule\n");
493 x->timer = NULL;
494 }
495 } else {
496 /* Ensure we don't false trigger in mmtimer_interrupt */
497 t->it.mmtimer.expires = 0;
498 }
499 t->it_overrun_last = t->it_overrun;
500 out:
501 spin_unlock(&x->lock);
502 spin_unlock_irqrestore(&t->it_lock, flags);
503 }
505 static int sgi_timer_create(struct k_itimer *timer)
506 {
507 /* Insure that a newly created timer is off */
508 timer->it.mmtimer.clock = TIMER_OFF;
509 return 0;
510 }
512 /* This does not really delete a timer. It just insures
513 * that the timer is not active
514 *
515 * Assumption: it_lock is already held with irq's disabled
516 */
517 static int sgi_timer_del(struct k_itimer *timr)
518 {
519 int i = timr->it.mmtimer.clock;
520 cnodeid_t nodeid = timr->it.mmtimer.node;
521 mmtimer_t *t = timers[nodeid] + i;
522 unsigned long irqflags;
524 if (i != TIMER_OFF) {
525 spin_lock_irqsave(&t->lock, irqflags);
526 mmtimer_disable_int(cnodeid_to_nasid(nodeid),i);
527 t->timer = NULL;
528 timr->it.mmtimer.clock = TIMER_OFF;
529 timr->it.mmtimer.expires = 0;
530 spin_unlock_irqrestore(&t->lock, irqflags);
531 }
532 return 0;
533 }
535 #define timespec_to_ns(x) ((x).tv_nsec + (x).tv_sec * NSEC_PER_SEC)
536 #define ns_to_timespec(ts, nsec) (ts).tv_sec = div_long_long_rem(nsec, NSEC_PER_SEC, &(ts).tv_nsec)
538 /* Assumption: it_lock is already held with irq's disabled */
539 static void sgi_timer_get(struct k_itimer *timr, struct itimerspec *cur_setting)
540 {
542 if (timr->it.mmtimer.clock == TIMER_OFF) {
543 cur_setting->it_interval.tv_nsec = 0;
544 cur_setting->it_interval.tv_sec = 0;
545 cur_setting->it_value.tv_nsec = 0;
546 cur_setting->it_value.tv_sec =0;
547 return;
548 }
550 ns_to_timespec(cur_setting->it_interval, timr->it.mmtimer.incr * sgi_clock_period);
551 ns_to_timespec(cur_setting->it_value, (timr->it.mmtimer.expires - rtc_time())* sgi_clock_period);
552 return;
553 }
556 static int sgi_timer_set(struct k_itimer *timr, int flags,
557 struct itimerspec * new_setting,
558 struct itimerspec * old_setting)
559 {
561 int i;
562 unsigned long when, period, irqflags;
563 int err = 0;
564 cnodeid_t nodeid;
565 mmtimer_t *base;
567 if (old_setting)
568 sgi_timer_get(timr, old_setting);
570 sgi_timer_del(timr);
571 when = timespec_to_ns(new_setting->it_value);
572 period = timespec_to_ns(new_setting->it_interval);
574 if (when == 0)
575 /* Clear timer */
576 return 0;
578 if (flags & TIMER_ABSTIME) {
579 struct timespec n;
580 unsigned long now;
582 getnstimeofday(&n);
583 now = timespec_to_ns(n);
584 if (when > now)
585 when -= now;
586 else
587 /* Fire the timer immediately */
588 when = 0;
589 }
591 /*
592 * Convert to sgi clock period. Need to keep rtc_time() as near as possible
593 * to getnstimeofday() in order to be as faithful as possible to the time
594 * specified.
595 */
596 when = (when + sgi_clock_period - 1) / sgi_clock_period + rtc_time();
597 period = (period + sgi_clock_period - 1) / sgi_clock_period;
599 /*
600 * We are allocating a local SHub comparator. If we would be moved to another
601 * cpu then another SHub may be local to us. Prohibit that by switching off
602 * preemption.
603 */
604 preempt_disable();
606 nodeid = cpu_to_node(smp_processor_id());
607 retry:
608 /* Don't use an allocated timer, or a deleted one that's pending */
609 for(i = 0; i< NUM_COMPARATORS; i++) {
610 base = timers[nodeid] + i;
611 if (!base->timer && !base->tasklet.state) {
612 break;
613 }
614 }
616 if (i == NUM_COMPARATORS) {
617 preempt_enable();
618 return -EBUSY;
619 }
621 spin_lock_irqsave(&base->lock, irqflags);
623 if (base->timer || base->tasklet.state != 0) {
624 spin_unlock_irqrestore(&base->lock, irqflags);
625 goto retry;
626 }
627 base->timer = timr;
628 base->cpu = smp_processor_id();
630 timr->it.mmtimer.clock = i;
631 timr->it.mmtimer.node = nodeid;
632 timr->it.mmtimer.incr = period;
633 timr->it.mmtimer.expires = when;
635 if (period == 0) {
636 if (!mmtimer_setup(i, when)) {
637 mmtimer_disable_int(-1, i);
638 posix_timer_event(timr, 0);
639 timr->it.mmtimer.expires = 0;
640 }
641 } else {
642 timr->it.mmtimer.expires -= period;
643 if (reschedule_periodic_timer(base))
644 err = -EINVAL;
645 }
647 spin_unlock_irqrestore(&base->lock, irqflags);
649 preempt_enable();
651 return err;
652 }
654 static struct k_clock sgi_clock = {
655 .res = 0,
656 .clock_set = sgi_clock_set,
657 .clock_get = sgi_clock_get,
658 .timer_create = sgi_timer_create,
659 .nsleep = do_posix_clock_nonanosleep,
660 .timer_set = sgi_timer_set,
661 .timer_del = sgi_timer_del,
662 .timer_get = sgi_timer_get
663 };
665 /**
666 * mmtimer_init - device initialization routine
667 *
668 * Does initial setup for the mmtimer device.
669 */
670 static int __init mmtimer_init(void)
671 {
672 unsigned i;
673 cnodeid_t node, maxn = -1;
675 if (!ia64_platform_is("sn2"))
676 return 0;
678 /*
679 * Sanity check the cycles/sec variable
680 */
681 if (sn_rtc_cycles_per_second < 100000) {
682 printk(KERN_ERR "%s: unable to determine clock frequency\n",
683 MMTIMER_NAME);
684 return -1;
685 }
687 mmtimer_femtoperiod = ((unsigned long)1E15 + sn_rtc_cycles_per_second /
688 2) / sn_rtc_cycles_per_second;
690 if (request_irq(SGI_MMTIMER_VECTOR, mmtimer_interrupt, IRQF_PERCPU, MMTIMER_NAME, NULL)) {
691 printk(KERN_WARNING "%s: unable to allocate interrupt.",
692 MMTIMER_NAME);
693 return -1;
694 }
696 if (misc_register(&mmtimer_miscdev)) {
697 printk(KERN_ERR "%s: failed to register device\n",
698 MMTIMER_NAME);
699 return -1;
700 }
702 /* Get max numbered node, calculate slots needed */
703 for_each_online_node(node) {
704 maxn = node;
705 }
706 maxn++;
708 /* Allocate list of node ptrs to mmtimer_t's */
709 timers = kmalloc(sizeof(mmtimer_t *)*maxn, GFP_KERNEL);
710 if (timers == NULL) {
711 printk(KERN_ERR "%s: failed to allocate memory for device\n",
712 MMTIMER_NAME);
713 return -1;
714 }
716 /* Allocate mmtimer_t's for each online node */
717 for_each_online_node(node) {
718 timers[node] = kmalloc_node(sizeof(mmtimer_t)*NUM_COMPARATORS, GFP_KERNEL, node);
719 if (timers[node] == NULL) {
720 printk(KERN_ERR "%s: failed to allocate memory for device\n",
721 MMTIMER_NAME);
722 return -1;
723 }
724 for (i=0; i< NUM_COMPARATORS; i++) {
725 mmtimer_t * base = timers[node] + i;
727 spin_lock_init(&base->lock);
728 base->timer = NULL;
729 base->cpu = 0;
730 base->i = i;
731 tasklet_init(&base->tasklet, mmtimer_tasklet,
732 (unsigned long) (base));
733 }
734 }
736 sgi_clock_period = sgi_clock.res = NSEC_PER_SEC / sn_rtc_cycles_per_second;
737 register_posix_clock(CLOCK_SGI_CYCLE, &sgi_clock);
739 printk(KERN_INFO "%s: v%s, %ld MHz\n", MMTIMER_DESC, MMTIMER_VERSION,
740 sn_rtc_cycles_per_second/(unsigned long)1E6);
742 return 0;
743 }
745 module_init(mmtimer_init);