blob: c92378121b4ca054fdce184963b14290a7c6bb55 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
Dimitri Sivanich76832c22006-01-06 11:33:41 -06002 * Timer device implementation for SGI SN platforms.
Linus Torvalds1da177e2005-04-16 15:20:36 -07003 *
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 *
Dimitri Sivanich76832c22006-01-06 11:33:41 -06008 * Copyright (c) 2001-2006 Silicon Graphics, Inc. All rights reserved.
Linus Torvalds1da177e2005-04-16 15:20:36 -07009 *
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 */
20
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/devfs_fs_kernel.h>
29#include <linux/mmtimer.h>
30#include <linux/miscdevice.h>
31#include <linux/posix-timers.h>
32#include <linux/interrupt.h>
33
34#include <asm/uaccess.h>
35#include <asm/sn/addrs.h>
36#include <asm/sn/intr.h>
37#include <asm/sn/shub_mmr.h>
38#include <asm/sn/nodepda.h>
39#include <asm/sn/shubio.h>
40
41MODULE_AUTHOR("Jesse Barnes <jbarnes@sgi.com>");
42MODULE_DESCRIPTION("SGI Altix RTC Timer");
43MODULE_LICENSE("GPL");
44
45/* name of the device, usually in /dev */
46#define MMTIMER_NAME "mmtimer"
47#define MMTIMER_DESC "SGI Altix RTC Timer"
Dimitri Sivanich76832c22006-01-06 11:33:41 -060048#define MMTIMER_VERSION "2.1"
Linus Torvalds1da177e2005-04-16 15:20:36 -070049
50#define RTC_BITS 55 /* 55 bits for this implementation */
51
52extern unsigned long sn_rtc_cycles_per_second;
53
54#define RTC_COUNTER_ADDR ((long *)LOCAL_MMR_ADDR(SH_RTC))
55
56#define rtc_time() (*RTC_COUNTER_ADDR)
57
58static int mmtimer_ioctl(struct inode *inode, struct file *file,
59 unsigned int cmd, unsigned long arg);
60static int mmtimer_mmap(struct file *file, struct vm_area_struct *vma);
61
62/*
63 * Period in femtoseconds (10^-15 s)
64 */
65static unsigned long mmtimer_femtoperiod = 0;
66
67static struct file_operations mmtimer_fops = {
68 .owner = THIS_MODULE,
69 .mmap = mmtimer_mmap,
70 .ioctl = mmtimer_ioctl,
71};
72
73/*
74 * We only have comparison registers RTC1-4 currently available per
75 * node. RTC0 is used by SAL.
76 */
77#define NUM_COMPARATORS 3
78/* Check for an RTC interrupt pending */
79static int inline mmtimer_int_pending(int comparator)
80{
81 if (HUB_L((unsigned long *)LOCAL_MMR_ADDR(SH_EVENT_OCCURRED)) &
82 SH_EVENT_OCCURRED_RTC1_INT_MASK << comparator)
83 return 1;
84 else
85 return 0;
86}
87/* Clear the RTC interrupt pending bit */
88static void inline mmtimer_clr_int_pending(int comparator)
89{
90 HUB_S((u64 *)LOCAL_MMR_ADDR(SH_EVENT_OCCURRED_ALIAS),
91 SH_EVENT_OCCURRED_RTC1_INT_MASK << comparator);
92}
93
94/* Setup timer on comparator RTC1 */
95static void inline mmtimer_setup_int_0(u64 expires)
96{
97 u64 val;
98
99 /* Disable interrupt */
100 HUB_S((u64 *)LOCAL_MMR_ADDR(SH_RTC1_INT_ENABLE), 0UL);
101
102 /* Initialize comparator value */
103 HUB_S((u64 *)LOCAL_MMR_ADDR(SH_INT_CMPB), -1L);
104
105 /* Clear pending bit */
106 mmtimer_clr_int_pending(0);
107
108 val = ((u64)SGI_MMTIMER_VECTOR << SH_RTC1_INT_CONFIG_IDX_SHFT) |
109 ((u64)cpu_physical_id(smp_processor_id()) <<
110 SH_RTC1_INT_CONFIG_PID_SHFT);
111
112 /* Set configuration */
113 HUB_S((u64 *)LOCAL_MMR_ADDR(SH_RTC1_INT_CONFIG), val);
114
115 /* Enable RTC interrupts */
116 HUB_S((u64 *)LOCAL_MMR_ADDR(SH_RTC1_INT_ENABLE), 1UL);
117
118 /* Initialize comparator value */
119 HUB_S((u64 *)LOCAL_MMR_ADDR(SH_INT_CMPB), expires);
120
121
122}
123
124/* Setup timer on comparator RTC2 */
125static void inline mmtimer_setup_int_1(u64 expires)
126{
127 u64 val;
128
129 HUB_S((u64 *)LOCAL_MMR_ADDR(SH_RTC2_INT_ENABLE), 0UL);
130
131 HUB_S((u64 *)LOCAL_MMR_ADDR(SH_INT_CMPC), -1L);
132
133 mmtimer_clr_int_pending(1);
134
135 val = ((u64)SGI_MMTIMER_VECTOR << SH_RTC2_INT_CONFIG_IDX_SHFT) |
136 ((u64)cpu_physical_id(smp_processor_id()) <<
137 SH_RTC2_INT_CONFIG_PID_SHFT);
138
139 HUB_S((u64 *)LOCAL_MMR_ADDR(SH_RTC2_INT_CONFIG), val);
140
141 HUB_S((u64 *)LOCAL_MMR_ADDR(SH_RTC2_INT_ENABLE), 1UL);
142
143 HUB_S((u64 *)LOCAL_MMR_ADDR(SH_INT_CMPC), expires);
144}
145
146/* Setup timer on comparator RTC3 */
147static void inline mmtimer_setup_int_2(u64 expires)
148{
149 u64 val;
150
151 HUB_S((u64 *)LOCAL_MMR_ADDR(SH_RTC3_INT_ENABLE), 0UL);
152
153 HUB_S((u64 *)LOCAL_MMR_ADDR(SH_INT_CMPD), -1L);
154
155 mmtimer_clr_int_pending(2);
156
157 val = ((u64)SGI_MMTIMER_VECTOR << SH_RTC3_INT_CONFIG_IDX_SHFT) |
158 ((u64)cpu_physical_id(smp_processor_id()) <<
159 SH_RTC3_INT_CONFIG_PID_SHFT);
160
161 HUB_S((u64 *)LOCAL_MMR_ADDR(SH_RTC3_INT_CONFIG), val);
162
163 HUB_S((u64 *)LOCAL_MMR_ADDR(SH_RTC3_INT_ENABLE), 1UL);
164
165 HUB_S((u64 *)LOCAL_MMR_ADDR(SH_INT_CMPD), expires);
166}
167
168/*
169 * This function must be called with interrupts disabled and preemption off
170 * in order to insure that the setup succeeds in a deterministic time frame.
171 * It will check if the interrupt setup succeeded.
172 */
173static int inline mmtimer_setup(int comparator, unsigned long expires)
174{
175
176 switch (comparator) {
177 case 0:
178 mmtimer_setup_int_0(expires);
179 break;
180 case 1:
181 mmtimer_setup_int_1(expires);
182 break;
183 case 2:
184 mmtimer_setup_int_2(expires);
185 break;
186 }
187 /* We might've missed our expiration time */
188 if (rtc_time() < expires)
189 return 1;
190
191 /*
192 * If an interrupt is already pending then its okay
193 * if not then we failed
194 */
195 return mmtimer_int_pending(comparator);
196}
197
198static int inline mmtimer_disable_int(long nasid, int comparator)
199{
200 switch (comparator) {
201 case 0:
202 nasid == -1 ? HUB_S((u64 *)LOCAL_MMR_ADDR(SH_RTC1_INT_ENABLE),
203 0UL) : REMOTE_HUB_S(nasid, SH_RTC1_INT_ENABLE, 0UL);
204 break;
205 case 1:
206 nasid == -1 ? HUB_S((u64 *)LOCAL_MMR_ADDR(SH_RTC2_INT_ENABLE),
207 0UL) : REMOTE_HUB_S(nasid, SH_RTC2_INT_ENABLE, 0UL);
208 break;
209 case 2:
210 nasid == -1 ? HUB_S((u64 *)LOCAL_MMR_ADDR(SH_RTC3_INT_ENABLE),
211 0UL) : REMOTE_HUB_S(nasid, SH_RTC3_INT_ENABLE, 0UL);
212 break;
213 default:
214 return -EFAULT;
215 }
216 return 0;
217}
218
219#define TIMER_OFF 0xbadcabLL
220
221/* There is one of these for each comparator */
222typedef struct mmtimer {
223 spinlock_t lock ____cacheline_aligned;
224 struct k_itimer *timer;
225 int i;
226 int cpu;
227 struct tasklet_struct tasklet;
228} mmtimer_t;
229
Dimitri Sivanich76832c22006-01-06 11:33:41 -0600230static mmtimer_t ** timers;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700231
232/**
233 * mmtimer_ioctl - ioctl interface for /dev/mmtimer
234 * @inode: inode of the device
235 * @file: file structure for the device
236 * @cmd: command to execute
237 * @arg: optional argument to command
238 *
239 * Executes the command specified by @cmd. Returns 0 for success, < 0 for
240 * failure.
241 *
242 * Valid commands:
243 *
244 * %MMTIMER_GETOFFSET - Should return the offset (relative to the start
245 * of the page where the registers are mapped) for the counter in question.
246 *
247 * %MMTIMER_GETRES - Returns the resolution of the clock in femto (10^-15)
248 * seconds
249 *
250 * %MMTIMER_GETFREQ - Copies the frequency of the clock in Hz to the address
251 * specified by @arg
252 *
253 * %MMTIMER_GETBITS - Returns the number of bits in the clock's counter
254 *
255 * %MMTIMER_MMAPAVAIL - Returns 1 if the registers can be mmap'd into userspace
256 *
257 * %MMTIMER_GETCOUNTER - Gets the current value in the counter and places it
258 * in the address specified by @arg.
259 */
260static int mmtimer_ioctl(struct inode *inode, struct file *file,
261 unsigned int cmd, unsigned long arg)
262{
263 int ret = 0;
264
265 switch (cmd) {
266 case MMTIMER_GETOFFSET: /* offset of the counter */
267 /*
268 * SN RTC registers are on their own 64k page
269 */
270 if(PAGE_SIZE <= (1 << 16))
271 ret = (((long)RTC_COUNTER_ADDR) & (PAGE_SIZE-1)) / 8;
272 else
273 ret = -ENOSYS;
274 break;
275
276 case MMTIMER_GETRES: /* resolution of the clock in 10^-15 s */
277 if(copy_to_user((unsigned long __user *)arg,
278 &mmtimer_femtoperiod, sizeof(unsigned long)))
279 return -EFAULT;
280 break;
281
282 case MMTIMER_GETFREQ: /* frequency in Hz */
283 if(copy_to_user((unsigned long __user *)arg,
284 &sn_rtc_cycles_per_second,
285 sizeof(unsigned long)))
286 return -EFAULT;
287 ret = 0;
288 break;
289
290 case MMTIMER_GETBITS: /* number of bits in the clock */
291 ret = RTC_BITS;
292 break;
293
294 case MMTIMER_MMAPAVAIL: /* can we mmap the clock into userspace? */
295 ret = (PAGE_SIZE <= (1 << 16)) ? 1 : 0;
296 break;
297
298 case MMTIMER_GETCOUNTER:
299 if(copy_to_user((unsigned long __user *)arg,
300 RTC_COUNTER_ADDR, sizeof(unsigned long)))
301 return -EFAULT;
302 break;
303 default:
304 ret = -ENOSYS;
305 break;
306 }
307
308 return ret;
309}
310
311/**
312 * mmtimer_mmap - maps the clock's registers into userspace
313 * @file: file structure for the device
314 * @vma: VMA to map the registers into
315 *
316 * Calls remap_pfn_range() to map the clock's registers into
317 * the calling process' address space.
318 */
319static int mmtimer_mmap(struct file *file, struct vm_area_struct *vma)
320{
321 unsigned long mmtimer_addr;
322
323 if (vma->vm_end - vma->vm_start != PAGE_SIZE)
324 return -EINVAL;
325
326 if (vma->vm_flags & VM_WRITE)
327 return -EPERM;
328
329 if (PAGE_SIZE > (1 << 16))
330 return -ENOSYS;
331
332 vma->vm_flags |= (VM_IO | VM_SHM | VM_LOCKED );
333 vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
334
335 mmtimer_addr = __pa(RTC_COUNTER_ADDR);
336 mmtimer_addr &= ~(PAGE_SIZE - 1);
337 mmtimer_addr &= 0xfffffffffffffffUL;
338
339 if (remap_pfn_range(vma, vma->vm_start, mmtimer_addr >> PAGE_SHIFT,
340 PAGE_SIZE, vma->vm_page_prot)) {
341 printk(KERN_ERR "remap_pfn_range failed in mmtimer.c\n");
342 return -EAGAIN;
343 }
344
345 return 0;
346}
347
348static struct miscdevice mmtimer_miscdev = {
349 SGI_MMTIMER,
350 MMTIMER_NAME,
351 &mmtimer_fops
352};
353
354static struct timespec sgi_clock_offset;
355static int sgi_clock_period;
356
357/*
358 * Posix Timer Interface
359 */
360
361static struct timespec sgi_clock_offset;
362static int sgi_clock_period;
363
364static int sgi_clock_get(clockid_t clockid, struct timespec *tp)
365{
366 u64 nsec;
367
368 nsec = rtc_time() * sgi_clock_period
369 + sgi_clock_offset.tv_nsec;
370 tp->tv_sec = div_long_long_rem(nsec, NSEC_PER_SEC, &tp->tv_nsec)
371 + sgi_clock_offset.tv_sec;
372 return 0;
373};
374
375static int sgi_clock_set(clockid_t clockid, struct timespec *tp)
376{
377
378 u64 nsec;
379 u64 rem;
380
381 nsec = rtc_time() * sgi_clock_period;
382
383 sgi_clock_offset.tv_sec = tp->tv_sec - div_long_long_rem(nsec, NSEC_PER_SEC, &rem);
384
385 if (rem <= tp->tv_nsec)
386 sgi_clock_offset.tv_nsec = tp->tv_sec - rem;
387 else {
388 sgi_clock_offset.tv_nsec = tp->tv_sec + NSEC_PER_SEC - rem;
389 sgi_clock_offset.tv_sec--;
390 }
391 return 0;
392}
393
394/*
395 * Schedule the next periodic interrupt. This function will attempt
396 * to schedule a periodic interrupt later if necessary. If the scheduling
397 * of an interrupt fails then the time to skip is lengthened
398 * exponentially in order to ensure that the next interrupt
399 * can be properly scheduled..
400 */
401static int inline reschedule_periodic_timer(mmtimer_t *x)
402{
403 int n;
404 struct k_itimer *t = x->timer;
405
406 t->it.mmtimer.clock = x->i;
407 t->it_overrun--;
408
409 n = 0;
410 do {
411
412 t->it.mmtimer.expires += t->it.mmtimer.incr << n;
413 t->it_overrun += 1 << n;
414 n++;
415 if (n > 20)
416 return 1;
417
418 } while (!mmtimer_setup(x->i, t->it.mmtimer.expires));
419
420 return 0;
421}
422
423/**
424 * mmtimer_interrupt - timer interrupt handler
425 * @irq: irq received
426 * @dev_id: device the irq came from
427 * @regs: register state upon receipt of the interrupt
428 *
429 * Called when one of the comarators matches the counter, This
430 * routine will send signals to processes that have requested
431 * them.
432 *
433 * This interrupt is run in an interrupt context
434 * by the SHUB. It is therefore safe to locally access SHub
435 * registers.
436 */
437static irqreturn_t
438mmtimer_interrupt(int irq, void *dev_id, struct pt_regs *regs)
439{
440 int i;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700441 unsigned long expires = 0;
442 int result = IRQ_NONE;
Dimitri Sivanich76832c22006-01-06 11:33:41 -0600443 unsigned indx = cpu_to_node(smp_processor_id());
Linus Torvalds1da177e2005-04-16 15:20:36 -0700444
445 /*
446 * Do this once for each comparison register
447 */
448 for (i = 0; i < NUM_COMPARATORS; i++) {
Dimitri Sivanich76832c22006-01-06 11:33:41 -0600449 mmtimer_t *base = timers[indx] + i;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700450 /* Make sure this doesn't get reused before tasklet_sched */
Dimitri Sivanich76832c22006-01-06 11:33:41 -0600451 spin_lock(&base->lock);
452 if (base->cpu == smp_processor_id()) {
453 if (base->timer)
454 expires = base->timer->it.mmtimer.expires;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700455 /* expires test won't work with shared irqs */
456 if ((mmtimer_int_pending(i) > 0) ||
457 (expires && (expires < rtc_time()))) {
458 mmtimer_clr_int_pending(i);
Dimitri Sivanich76832c22006-01-06 11:33:41 -0600459 tasklet_schedule(&base->tasklet);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700460 result = IRQ_HANDLED;
461 }
462 }
Dimitri Sivanich76832c22006-01-06 11:33:41 -0600463 spin_unlock(&base->lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700464 expires = 0;
465 }
466 return result;
467}
468
469void mmtimer_tasklet(unsigned long data) {
470 mmtimer_t *x = (mmtimer_t *)data;
471 struct k_itimer *t = x->timer;
472 unsigned long flags;
473
474 if (t == NULL)
475 return;
476
477 /* Send signal and deal with periodic signals */
478 spin_lock_irqsave(&t->it_lock, flags);
479 spin_lock(&x->lock);
480 /* If timer was deleted between interrupt and here, leave */
481 if (t != x->timer)
482 goto out;
483 t->it_overrun = 0;
484
Christoph Lameter8d38ead2005-04-16 15:23:53 -0700485 if (posix_timer_event(t, 0) != 0) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700486
487 // printk(KERN_WARNING "mmtimer: cannot deliver signal.\n");
488
489 t->it_overrun++;
490 }
491 if(t->it.mmtimer.incr) {
492 /* Periodic timer */
493 if (reschedule_periodic_timer(x)) {
494 printk(KERN_WARNING "mmtimer: unable to reschedule\n");
495 x->timer = NULL;
496 }
497 } else {
498 /* Ensure we don't false trigger in mmtimer_interrupt */
499 t->it.mmtimer.expires = 0;
500 }
501 t->it_overrun_last = t->it_overrun;
502out:
503 spin_unlock(&x->lock);
504 spin_unlock_irqrestore(&t->it_lock, flags);
505}
506
507static int sgi_timer_create(struct k_itimer *timer)
508{
509 /* Insure that a newly created timer is off */
510 timer->it.mmtimer.clock = TIMER_OFF;
511 return 0;
512}
513
514/* This does not really delete a timer. It just insures
515 * that the timer is not active
516 *
517 * Assumption: it_lock is already held with irq's disabled
518 */
519static int sgi_timer_del(struct k_itimer *timr)
520{
521 int i = timr->it.mmtimer.clock;
522 cnodeid_t nodeid = timr->it.mmtimer.node;
Dimitri Sivanich76832c22006-01-06 11:33:41 -0600523 mmtimer_t *t = timers[nodeid] + i;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700524 unsigned long irqflags;
525
526 if (i != TIMER_OFF) {
527 spin_lock_irqsave(&t->lock, irqflags);
528 mmtimer_disable_int(cnodeid_to_nasid(nodeid),i);
529 t->timer = NULL;
530 timr->it.mmtimer.clock = TIMER_OFF;
531 timr->it.mmtimer.expires = 0;
532 spin_unlock_irqrestore(&t->lock, irqflags);
533 }
534 return 0;
535}
536
537#define timespec_to_ns(x) ((x).tv_nsec + (x).tv_sec * NSEC_PER_SEC)
538#define ns_to_timespec(ts, nsec) (ts).tv_sec = div_long_long_rem(nsec, NSEC_PER_SEC, &(ts).tv_nsec)
539
540/* Assumption: it_lock is already held with irq's disabled */
541static void sgi_timer_get(struct k_itimer *timr, struct itimerspec *cur_setting)
542{
543
544 if (timr->it.mmtimer.clock == TIMER_OFF) {
545 cur_setting->it_interval.tv_nsec = 0;
546 cur_setting->it_interval.tv_sec = 0;
547 cur_setting->it_value.tv_nsec = 0;
548 cur_setting->it_value.tv_sec =0;
549 return;
550 }
551
552 ns_to_timespec(cur_setting->it_interval, timr->it.mmtimer.incr * sgi_clock_period);
553 ns_to_timespec(cur_setting->it_value, (timr->it.mmtimer.expires - rtc_time())* sgi_clock_period);
554 return;
555}
556
557
558static int sgi_timer_set(struct k_itimer *timr, int flags,
559 struct itimerspec * new_setting,
560 struct itimerspec * old_setting)
561{
562
563 int i;
564 unsigned long when, period, irqflags;
565 int err = 0;
566 cnodeid_t nodeid;
567 mmtimer_t *base;
568
569 if (old_setting)
570 sgi_timer_get(timr, old_setting);
571
572 sgi_timer_del(timr);
573 when = timespec_to_ns(new_setting->it_value);
574 period = timespec_to_ns(new_setting->it_interval);
575
576 if (when == 0)
577 /* Clear timer */
578 return 0;
579
580 if (flags & TIMER_ABSTIME) {
581 struct timespec n;
582 unsigned long now;
583
584 getnstimeofday(&n);
585 now = timespec_to_ns(n);
586 if (when > now)
587 when -= now;
588 else
589 /* Fire the timer immediately */
590 when = 0;
591 }
592
593 /*
594 * Convert to sgi clock period. Need to keep rtc_time() as near as possible
595 * to getnstimeofday() in order to be as faithful as possible to the time
596 * specified.
597 */
598 when = (when + sgi_clock_period - 1) / sgi_clock_period + rtc_time();
599 period = (period + sgi_clock_period - 1) / sgi_clock_period;
600
601 /*
602 * We are allocating a local SHub comparator. If we would be moved to another
603 * cpu then another SHub may be local to us. Prohibit that by switching off
604 * preemption.
605 */
606 preempt_disable();
607
Tony Luck55642d32005-09-15 17:00:10 -0700608 nodeid = cpu_to_node(smp_processor_id());
Linus Torvalds1da177e2005-04-16 15:20:36 -0700609retry:
610 /* Don't use an allocated timer, or a deleted one that's pending */
611 for(i = 0; i< NUM_COMPARATORS; i++) {
Dimitri Sivanich76832c22006-01-06 11:33:41 -0600612 base = timers[nodeid] + i;
613 if (!base->timer && !base->tasklet.state) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700614 break;
615 }
616 }
617
618 if (i == NUM_COMPARATORS) {
619 preempt_enable();
620 return -EBUSY;
621 }
622
Dimitri Sivanich76832c22006-01-06 11:33:41 -0600623 spin_lock_irqsave(&base->lock, irqflags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700624
Dimitri Sivanich76832c22006-01-06 11:33:41 -0600625 if (base->timer || base->tasklet.state != 0) {
626 spin_unlock_irqrestore(&base->lock, irqflags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700627 goto retry;
628 }
Dimitri Sivanich76832c22006-01-06 11:33:41 -0600629 base->timer = timr;
630 base->cpu = smp_processor_id();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700631
632 timr->it.mmtimer.clock = i;
633 timr->it.mmtimer.node = nodeid;
634 timr->it.mmtimer.incr = period;
635 timr->it.mmtimer.expires = when;
636
637 if (period == 0) {
638 if (!mmtimer_setup(i, when)) {
639 mmtimer_disable_int(-1, i);
640 posix_timer_event(timr, 0);
641 timr->it.mmtimer.expires = 0;
642 }
643 } else {
644 timr->it.mmtimer.expires -= period;
Dimitri Sivanich76832c22006-01-06 11:33:41 -0600645 if (reschedule_periodic_timer(base))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700646 err = -EINVAL;
647 }
648
Dimitri Sivanich76832c22006-01-06 11:33:41 -0600649 spin_unlock_irqrestore(&base->lock, irqflags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700650
651 preempt_enable();
652
653 return err;
654}
655
656static struct k_clock sgi_clock = {
657 .res = 0,
658 .clock_set = sgi_clock_set,
659 .clock_get = sgi_clock_get,
660 .timer_create = sgi_timer_create,
661 .nsleep = do_posix_clock_nonanosleep,
662 .timer_set = sgi_timer_set,
663 .timer_del = sgi_timer_del,
664 .timer_get = sgi_timer_get
665};
666
667/**
668 * mmtimer_init - device initialization routine
669 *
670 * Does initial setup for the mmtimer device.
671 */
672static int __init mmtimer_init(void)
673{
674 unsigned i;
Dimitri Sivanich76832c22006-01-06 11:33:41 -0600675 cnodeid_t node, maxn = -1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700676
677 if (!ia64_platform_is("sn2"))
678 return -1;
679
680 /*
681 * Sanity check the cycles/sec variable
682 */
683 if (sn_rtc_cycles_per_second < 100000) {
684 printk(KERN_ERR "%s: unable to determine clock frequency\n",
685 MMTIMER_NAME);
686 return -1;
687 }
688
689 mmtimer_femtoperiod = ((unsigned long)1E15 + sn_rtc_cycles_per_second /
690 2) / sn_rtc_cycles_per_second;
691
Linus Torvalds1da177e2005-04-16 15:20:36 -0700692 if (request_irq(SGI_MMTIMER_VECTOR, mmtimer_interrupt, SA_PERCPU_IRQ, MMTIMER_NAME, NULL)) {
693 printk(KERN_WARNING "%s: unable to allocate interrupt.",
694 MMTIMER_NAME);
695 return -1;
696 }
697
698 strcpy(mmtimer_miscdev.devfs_name, MMTIMER_NAME);
699 if (misc_register(&mmtimer_miscdev)) {
700 printk(KERN_ERR "%s: failed to register device\n",
701 MMTIMER_NAME);
702 return -1;
703 }
704
Dimitri Sivanich76832c22006-01-06 11:33:41 -0600705 /* Get max numbered node, calculate slots needed */
706 for_each_online_node(node) {
707 maxn = node;
708 }
709 maxn++;
710
711 /* Allocate list of node ptrs to mmtimer_t's */
712 timers = kmalloc(sizeof(mmtimer_t *)*maxn, GFP_KERNEL);
713 if (timers == NULL) {
714 printk(KERN_ERR "%s: failed to allocate memory for device\n",
715 MMTIMER_NAME);
716 return -1;
717 }
718
719 /* Allocate mmtimer_t's for each online node */
720 for_each_online_node(node) {
721 timers[node] = kmalloc_node(sizeof(mmtimer_t)*NUM_COMPARATORS, GFP_KERNEL, node);
722 if (timers[node] == NULL) {
723 printk(KERN_ERR "%s: failed to allocate memory for device\n",
724 MMTIMER_NAME);
725 return -1;
726 }
727 for (i=0; i< NUM_COMPARATORS; i++) {
728 mmtimer_t * base = timers[node] + i;
729
730 spin_lock_init(&base->lock);
731 base->timer = NULL;
732 base->cpu = 0;
733 base->i = i;
734 tasklet_init(&base->tasklet, mmtimer_tasklet,
735 (unsigned long) (base));
736 }
737 }
738
Linus Torvalds1da177e2005-04-16 15:20:36 -0700739 sgi_clock_period = sgi_clock.res = NSEC_PER_SEC / sn_rtc_cycles_per_second;
740 register_posix_clock(CLOCK_SGI_CYCLE, &sgi_clock);
741
742 printk(KERN_INFO "%s: v%s, %ld MHz\n", MMTIMER_DESC, MMTIMER_VERSION,
743 sn_rtc_cycles_per_second/(unsigned long)1E6);
744
745 return 0;
746}
747
748module_init(mmtimer_init);
749