2 * Timer device implementation for SGI SN platforms.
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
8 * Copyright (c) 2001-2006 Silicon Graphics, Inc. All rights reserved.
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
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
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>
29 #include <linux/mmtimer.h>
30 #include <linux/miscdevice.h>
31 #include <linux/posix-timers.h>
32 #include <linux/interrupt.h>
33 #include <linux/time.h>
34 #include <linux/math64.h>
35 #include <linux/mutex.h>
36 #include <linux/slab.h>
38 #include <asm/uaccess.h>
39 #include <asm/sn/addrs.h>
40 #include <asm/sn/intr.h>
41 #include <asm/sn/shub_mmr.h>
42 #include <asm/sn/nodepda.h>
43 #include <asm/sn/shubio.h>
45 MODULE_AUTHOR("Jesse Barnes <jbarnes@sgi.com>");
46 MODULE_DESCRIPTION("SGI Altix RTC Timer");
47 MODULE_LICENSE("GPL");
49 /* name of the device, usually in /dev */
50 #define MMTIMER_NAME "mmtimer"
51 #define MMTIMER_DESC "SGI Altix RTC Timer"
52 #define MMTIMER_VERSION "2.1"
54 #define RTC_BITS 55 /* 55 bits for this implementation */
56 extern unsigned long sn_rtc_cycles_per_second
;
58 #define RTC_COUNTER_ADDR ((long *)LOCAL_MMR_ADDR(SH_RTC))
60 #define rtc_time() (*RTC_COUNTER_ADDR)
62 static DEFINE_MUTEX(mmtimer_mutex
);
63 static long mmtimer_ioctl(struct file
*file
, unsigned int cmd
,
65 static int mmtimer_mmap(struct file
*file
, struct vm_area_struct
*vma
);
68 * Period in femtoseconds (10^-15 s)
70 static unsigned long mmtimer_femtoperiod
= 0;
72 static const struct file_operations mmtimer_fops
= {
75 .unlocked_ioctl
= mmtimer_ioctl
,
79 * We only have comparison registers RTC1-4 currently available per
80 * node. RTC0 is used by SAL.
82 /* Check for an RTC interrupt pending */
83 static int mmtimer_int_pending(int comparator
)
85 if (HUB_L((unsigned long *)LOCAL_MMR_ADDR(SH_EVENT_OCCURRED
)) &
86 SH_EVENT_OCCURRED_RTC1_INT_MASK
<< comparator
)
92 /* Clear the RTC interrupt pending bit */
93 static void mmtimer_clr_int_pending(int comparator
)
95 HUB_S((u64
*)LOCAL_MMR_ADDR(SH_EVENT_OCCURRED_ALIAS
),
96 SH_EVENT_OCCURRED_RTC1_INT_MASK
<< comparator
);
99 /* Setup timer on comparator RTC1 */
100 static void mmtimer_setup_int_0(int cpu
, u64 expires
)
104 /* Disable interrupt */
105 HUB_S((u64
*)LOCAL_MMR_ADDR(SH_RTC1_INT_ENABLE
), 0UL);
107 /* Initialize comparator value */
108 HUB_S((u64
*)LOCAL_MMR_ADDR(SH_INT_CMPB
), -1L);
110 /* Clear pending bit */
111 mmtimer_clr_int_pending(0);
113 val
= ((u64
)SGI_MMTIMER_VECTOR
<< SH_RTC1_INT_CONFIG_IDX_SHFT
) |
114 ((u64
)cpu_physical_id(cpu
) <<
115 SH_RTC1_INT_CONFIG_PID_SHFT
);
117 /* Set configuration */
118 HUB_S((u64
*)LOCAL_MMR_ADDR(SH_RTC1_INT_CONFIG
), val
);
120 /* Enable RTC interrupts */
121 HUB_S((u64
*)LOCAL_MMR_ADDR(SH_RTC1_INT_ENABLE
), 1UL);
123 /* Initialize comparator value */
124 HUB_S((u64
*)LOCAL_MMR_ADDR(SH_INT_CMPB
), expires
);
129 /* Setup timer on comparator RTC2 */
130 static void mmtimer_setup_int_1(int cpu
, u64 expires
)
134 HUB_S((u64
*)LOCAL_MMR_ADDR(SH_RTC2_INT_ENABLE
), 0UL);
136 HUB_S((u64
*)LOCAL_MMR_ADDR(SH_INT_CMPC
), -1L);
138 mmtimer_clr_int_pending(1);
140 val
= ((u64
)SGI_MMTIMER_VECTOR
<< SH_RTC2_INT_CONFIG_IDX_SHFT
) |
141 ((u64
)cpu_physical_id(cpu
) <<
142 SH_RTC2_INT_CONFIG_PID_SHFT
);
144 HUB_S((u64
*)LOCAL_MMR_ADDR(SH_RTC2_INT_CONFIG
), val
);
146 HUB_S((u64
*)LOCAL_MMR_ADDR(SH_RTC2_INT_ENABLE
), 1UL);
148 HUB_S((u64
*)LOCAL_MMR_ADDR(SH_INT_CMPC
), expires
);
151 /* Setup timer on comparator RTC3 */
152 static void mmtimer_setup_int_2(int cpu
, u64 expires
)
156 HUB_S((u64
*)LOCAL_MMR_ADDR(SH_RTC3_INT_ENABLE
), 0UL);
158 HUB_S((u64
*)LOCAL_MMR_ADDR(SH_INT_CMPD
), -1L);
160 mmtimer_clr_int_pending(2);
162 val
= ((u64
)SGI_MMTIMER_VECTOR
<< SH_RTC3_INT_CONFIG_IDX_SHFT
) |
163 ((u64
)cpu_physical_id(cpu
) <<
164 SH_RTC3_INT_CONFIG_PID_SHFT
);
166 HUB_S((u64
*)LOCAL_MMR_ADDR(SH_RTC3_INT_CONFIG
), val
);
168 HUB_S((u64
*)LOCAL_MMR_ADDR(SH_RTC3_INT_ENABLE
), 1UL);
170 HUB_S((u64
*)LOCAL_MMR_ADDR(SH_INT_CMPD
), expires
);
174 * This function must be called with interrupts disabled and preemption off
175 * in order to insure that the setup succeeds in a deterministic time frame.
176 * It will check if the interrupt setup succeeded.
178 static int mmtimer_setup(int cpu
, int comparator
, unsigned long expires
)
181 switch (comparator
) {
183 mmtimer_setup_int_0(cpu
, expires
);
186 mmtimer_setup_int_1(cpu
, expires
);
189 mmtimer_setup_int_2(cpu
, expires
);
192 /* We might've missed our expiration time */
193 if (rtc_time() <= expires
)
197 * If an interrupt is already pending then its okay
198 * if not then we failed
200 return mmtimer_int_pending(comparator
);
203 static int mmtimer_disable_int(long nasid
, int comparator
)
205 switch (comparator
) {
207 nasid
== -1 ? HUB_S((u64
*)LOCAL_MMR_ADDR(SH_RTC1_INT_ENABLE
),
208 0UL) : REMOTE_HUB_S(nasid
, SH_RTC1_INT_ENABLE
, 0UL);
211 nasid
== -1 ? HUB_S((u64
*)LOCAL_MMR_ADDR(SH_RTC2_INT_ENABLE
),
212 0UL) : REMOTE_HUB_S(nasid
, SH_RTC2_INT_ENABLE
, 0UL);
215 nasid
== -1 ? HUB_S((u64
*)LOCAL_MMR_ADDR(SH_RTC3_INT_ENABLE
),
216 0UL) : REMOTE_HUB_S(nasid
, SH_RTC3_INT_ENABLE
, 0UL);
224 #define COMPARATOR 1 /* The comparator to use */
226 #define TIMER_OFF 0xbadcabLL /* Timer is not setup */
227 #define TIMER_SET 0 /* Comparator is set for this timer */
229 /* There is one of these for each timer */
232 struct k_itimer
*timer
;
236 struct mmtimer_node
{
237 spinlock_t lock ____cacheline_aligned
;
238 struct rb_root timer_head
;
239 struct rb_node
*next
;
240 struct tasklet_struct tasklet
;
242 static struct mmtimer_node
*timers
;
246 * Add a new mmtimer struct to the node's mmtimer list.
247 * This function assumes the struct mmtimer_node is locked.
249 static void mmtimer_add_list(struct mmtimer
*n
)
251 int nodeid
= n
->timer
->it
.mmtimer
.node
;
252 unsigned long expires
= n
->timer
->it
.mmtimer
.expires
;
253 struct rb_node
**link
= &timers
[nodeid
].timer_head
.rb_node
;
254 struct rb_node
*parent
= NULL
;
258 * Find the right place in the rbtree:
262 x
= rb_entry(parent
, struct mmtimer
, list
);
264 if (expires
< x
->timer
->it
.mmtimer
.expires
)
265 link
= &(*link
)->rb_left
;
267 link
= &(*link
)->rb_right
;
271 * Insert the timer to the rbtree and check whether it
272 * replaces the first pending timer
274 rb_link_node(&n
->list
, parent
, link
);
275 rb_insert_color(&n
->list
, &timers
[nodeid
].timer_head
);
277 if (!timers
[nodeid
].next
|| expires
< rb_entry(timers
[nodeid
].next
,
278 struct mmtimer
, list
)->timer
->it
.mmtimer
.expires
)
279 timers
[nodeid
].next
= &n
->list
;
283 * Set the comparator for the next timer.
284 * This function assumes the struct mmtimer_node is locked.
286 static void mmtimer_set_next_timer(int nodeid
)
288 struct mmtimer_node
*n
= &timers
[nodeid
];
297 x
= rb_entry(n
->next
, struct mmtimer
, list
);
299 if (!t
->it
.mmtimer
.incr
) {
300 /* Not an interval timer */
301 if (!mmtimer_setup(x
->cpu
, COMPARATOR
,
302 t
->it
.mmtimer
.expires
)) {
303 /* Late setup, fire now */
304 tasklet_schedule(&n
->tasklet
);
311 while (!mmtimer_setup(x
->cpu
, COMPARATOR
, t
->it
.mmtimer
.expires
)) {
313 struct rb_node
*next
;
314 t
->it
.mmtimer
.expires
+= t
->it
.mmtimer
.incr
<< o
;
315 t
->it_overrun
+= 1 << o
;
318 printk(KERN_ALERT
"mmtimer: cannot reschedule timer\n");
319 t
->it
.mmtimer
.clock
= TIMER_OFF
;
320 n
->next
= rb_next(&x
->list
);
321 rb_erase(&x
->list
, &n
->timer_head
);
326 e
= t
->it
.mmtimer
.expires
;
327 next
= rb_next(&x
->list
);
332 e1
= rb_entry(next
, struct mmtimer
, list
)->
333 timer
->it
.mmtimer
.expires
;
336 rb_erase(&x
->list
, &n
->timer_head
);
344 * mmtimer_ioctl - ioctl interface for /dev/mmtimer
345 * @file: file structure for the device
346 * @cmd: command to execute
347 * @arg: optional argument to command
349 * Executes the command specified by @cmd. Returns 0 for success, < 0 for
354 * %MMTIMER_GETOFFSET - Should return the offset (relative to the start
355 * of the page where the registers are mapped) for the counter in question.
357 * %MMTIMER_GETRES - Returns the resolution of the clock in femto (10^-15)
360 * %MMTIMER_GETFREQ - Copies the frequency of the clock in Hz to the address
363 * %MMTIMER_GETBITS - Returns the number of bits in the clock's counter
365 * %MMTIMER_MMAPAVAIL - Returns 1 if the registers can be mmap'd into userspace
367 * %MMTIMER_GETCOUNTER - Gets the current value in the counter and places it
368 * in the address specified by @arg.
370 static long mmtimer_ioctl(struct file
*file
, unsigned int cmd
,
375 mutex_lock(&mmtimer_mutex
);
378 case MMTIMER_GETOFFSET
: /* offset of the counter */
380 * SN RTC registers are on their own 64k page
382 if(PAGE_SIZE
<= (1 << 16))
383 ret
= (((long)RTC_COUNTER_ADDR
) & (PAGE_SIZE
-1)) / 8;
388 case MMTIMER_GETRES
: /* resolution of the clock in 10^-15 s */
389 if(copy_to_user((unsigned long __user
*)arg
,
390 &mmtimer_femtoperiod
, sizeof(unsigned long)))
394 case MMTIMER_GETFREQ
: /* frequency in Hz */
395 if(copy_to_user((unsigned long __user
*)arg
,
396 &sn_rtc_cycles_per_second
,
397 sizeof(unsigned long)))
401 case MMTIMER_GETBITS
: /* number of bits in the clock */
405 case MMTIMER_MMAPAVAIL
: /* can we mmap the clock into userspace? */
406 ret
= (PAGE_SIZE
<= (1 << 16)) ? 1 : 0;
409 case MMTIMER_GETCOUNTER
:
410 if(copy_to_user((unsigned long __user
*)arg
,
411 RTC_COUNTER_ADDR
, sizeof(unsigned long)))
418 mutex_unlock(&mmtimer_mutex
);
423 * mmtimer_mmap - maps the clock's registers into userspace
424 * @file: file structure for the device
425 * @vma: VMA to map the registers into
427 * Calls remap_pfn_range() to map the clock's registers into
428 * the calling process' address space.
430 static int mmtimer_mmap(struct file
*file
, struct vm_area_struct
*vma
)
432 unsigned long mmtimer_addr
;
434 if (vma
->vm_end
- vma
->vm_start
!= PAGE_SIZE
)
437 if (vma
->vm_flags
& VM_WRITE
)
440 if (PAGE_SIZE
> (1 << 16))
443 vma
->vm_page_prot
= pgprot_noncached(vma
->vm_page_prot
);
445 mmtimer_addr
= __pa(RTC_COUNTER_ADDR
);
446 mmtimer_addr
&= ~(PAGE_SIZE
- 1);
447 mmtimer_addr
&= 0xfffffffffffffffUL
;
449 if (remap_pfn_range(vma
, vma
->vm_start
, mmtimer_addr
>> PAGE_SHIFT
,
450 PAGE_SIZE
, vma
->vm_page_prot
)) {
451 printk(KERN_ERR
"remap_pfn_range failed in mmtimer.c\n");
458 static struct miscdevice mmtimer_miscdev
= {
464 static struct timespec sgi_clock_offset
;
465 static int sgi_clock_period
;
468 * Posix Timer Interface
471 static struct timespec sgi_clock_offset
;
472 static int sgi_clock_period
;
474 static int sgi_clock_get(clockid_t clockid
, struct timespec
*tp
)
478 nsec
= rtc_time() * sgi_clock_period
479 + sgi_clock_offset
.tv_nsec
;
480 *tp
= ns_to_timespec(nsec
);
481 tp
->tv_sec
+= sgi_clock_offset
.tv_sec
;
485 static int sgi_clock_set(clockid_t clockid
, struct timespec
*tp
)
491 nsec
= rtc_time() * sgi_clock_period
;
493 sgi_clock_offset
.tv_sec
= tp
->tv_sec
- div_u64_rem(nsec
, NSEC_PER_SEC
, &rem
);
495 if (rem
<= tp
->tv_nsec
)
496 sgi_clock_offset
.tv_nsec
= tp
->tv_sec
- rem
;
498 sgi_clock_offset
.tv_nsec
= tp
->tv_sec
+ NSEC_PER_SEC
- rem
;
499 sgi_clock_offset
.tv_sec
--;
505 * mmtimer_interrupt - timer interrupt handler
507 * @dev_id: device the irq came from
509 * Called when one of the comarators matches the counter, This
510 * routine will send signals to processes that have requested
513 * This interrupt is run in an interrupt context
514 * by the SHUB. It is therefore safe to locally access SHub
518 mmtimer_interrupt(int irq
, void *dev_id
)
520 unsigned long expires
= 0;
521 int result
= IRQ_NONE
;
522 unsigned indx
= cpu_to_node(smp_processor_id());
523 struct mmtimer
*base
;
525 spin_lock(&timers
[indx
].lock
);
526 base
= rb_entry(timers
[indx
].next
, struct mmtimer
, list
);
528 spin_unlock(&timers
[indx
].lock
);
532 if (base
->cpu
== smp_processor_id()) {
534 expires
= base
->timer
->it
.mmtimer
.expires
;
535 /* expires test won't work with shared irqs */
536 if ((mmtimer_int_pending(COMPARATOR
) > 0) ||
537 (expires
&& (expires
<= rtc_time()))) {
538 mmtimer_clr_int_pending(COMPARATOR
);
539 tasklet_schedule(&timers
[indx
].tasklet
);
540 result
= IRQ_HANDLED
;
543 spin_unlock(&timers
[indx
].lock
);
547 static void mmtimer_tasklet(unsigned long data
)
550 struct mmtimer_node
*mn
= &timers
[nodeid
];
555 /* Send signal and deal with periodic signals */
556 spin_lock_irqsave(&mn
->lock
, flags
);
560 x
= rb_entry(mn
->next
, struct mmtimer
, list
);
563 if (t
->it
.mmtimer
.clock
== TIMER_OFF
)
568 mn
->next
= rb_next(&x
->list
);
569 rb_erase(&x
->list
, &mn
->timer_head
);
571 if (posix_timer_event(t
, 0) != 0)
574 if(t
->it
.mmtimer
.incr
) {
575 t
->it
.mmtimer
.expires
+= t
->it
.mmtimer
.incr
;
578 /* Ensure we don't false trigger in mmtimer_interrupt */
579 t
->it
.mmtimer
.clock
= TIMER_OFF
;
580 t
->it
.mmtimer
.expires
= 0;
583 /* Set comparator for next timer, if there is one */
584 mmtimer_set_next_timer(nodeid
);
586 t
->it_overrun_last
= t
->it_overrun
;
588 spin_unlock_irqrestore(&mn
->lock
, flags
);
591 static int sgi_timer_create(struct k_itimer
*timer
)
593 /* Insure that a newly created timer is off */
594 timer
->it
.mmtimer
.clock
= TIMER_OFF
;
598 /* This does not really delete a timer. It just insures
599 * that the timer is not active
601 * Assumption: it_lock is already held with irq's disabled
603 static int sgi_timer_del(struct k_itimer
*timr
)
605 cnodeid_t nodeid
= timr
->it
.mmtimer
.node
;
606 unsigned long irqflags
;
608 spin_lock_irqsave(&timers
[nodeid
].lock
, irqflags
);
609 if (timr
->it
.mmtimer
.clock
!= TIMER_OFF
) {
610 unsigned long expires
= timr
->it
.mmtimer
.expires
;
611 struct rb_node
*n
= timers
[nodeid
].timer_head
.rb_node
;
612 struct mmtimer
*uninitialized_var(t
);
615 timr
->it
.mmtimer
.clock
= TIMER_OFF
;
616 timr
->it
.mmtimer
.expires
= 0;
619 t
= rb_entry(n
, struct mmtimer
, list
);
620 if (t
->timer
== timr
)
623 if (expires
< t
->timer
->it
.mmtimer
.expires
)
630 spin_unlock_irqrestore(&timers
[nodeid
].lock
, irqflags
);
634 if (timers
[nodeid
].next
== n
) {
635 timers
[nodeid
].next
= rb_next(n
);
639 rb_erase(n
, &timers
[nodeid
].timer_head
);
643 mmtimer_disable_int(cnodeid_to_nasid(nodeid
),
645 mmtimer_set_next_timer(nodeid
);
648 spin_unlock_irqrestore(&timers
[nodeid
].lock
, irqflags
);
652 /* Assumption: it_lock is already held with irq's disabled */
653 static void sgi_timer_get(struct k_itimer
*timr
, struct itimerspec
*cur_setting
)
656 if (timr
->it
.mmtimer
.clock
== TIMER_OFF
) {
657 cur_setting
->it_interval
.tv_nsec
= 0;
658 cur_setting
->it_interval
.tv_sec
= 0;
659 cur_setting
->it_value
.tv_nsec
= 0;
660 cur_setting
->it_value
.tv_sec
=0;
664 cur_setting
->it_interval
= ns_to_timespec(timr
->it
.mmtimer
.incr
* sgi_clock_period
);
665 cur_setting
->it_value
= ns_to_timespec((timr
->it
.mmtimer
.expires
- rtc_time()) * sgi_clock_period
);
669 static int sgi_timer_set(struct k_itimer
*timr
, int flags
,
670 struct itimerspec
* new_setting
,
671 struct itimerspec
* old_setting
)
673 unsigned long when
, period
, irqflags
;
676 struct mmtimer
*base
;
680 sgi_timer_get(timr
, old_setting
);
683 when
= timespec_to_ns(&new_setting
->it_value
);
684 period
= timespec_to_ns(&new_setting
->it_interval
);
690 base
= kmalloc(sizeof(struct mmtimer
), GFP_KERNEL
);
694 if (flags
& TIMER_ABSTIME
) {
699 now
= timespec_to_ns(&n
);
703 /* Fire the timer immediately */
708 * Convert to sgi clock period. Need to keep rtc_time() as near as possible
709 * to getnstimeofday() in order to be as faithful as possible to the time
712 when
= (when
+ sgi_clock_period
- 1) / sgi_clock_period
+ rtc_time();
713 period
= (period
+ sgi_clock_period
- 1) / sgi_clock_period
;
716 * We are allocating a local SHub comparator. If we would be moved to another
717 * cpu then another SHub may be local to us. Prohibit that by switching off
722 nodeid
= cpu_to_node(smp_processor_id());
724 /* Lock the node timer structure */
725 spin_lock_irqsave(&timers
[nodeid
].lock
, irqflags
);
728 base
->cpu
= smp_processor_id();
730 timr
->it
.mmtimer
.clock
= TIMER_SET
;
731 timr
->it
.mmtimer
.node
= nodeid
;
732 timr
->it
.mmtimer
.incr
= period
;
733 timr
->it
.mmtimer
.expires
= when
;
735 n
= timers
[nodeid
].next
;
737 /* Add the new struct mmtimer to node's timer list */
738 mmtimer_add_list(base
);
740 if (timers
[nodeid
].next
== n
) {
741 /* No need to reprogram comparator for now */
742 spin_unlock_irqrestore(&timers
[nodeid
].lock
, irqflags
);
747 /* We need to reprogram the comparator */
749 mmtimer_disable_int(cnodeid_to_nasid(nodeid
), COMPARATOR
);
751 mmtimer_set_next_timer(nodeid
);
753 /* Unlock the node timer structure */
754 spin_unlock_irqrestore(&timers
[nodeid
].lock
, irqflags
);
761 static struct k_clock sgi_clock
= {
763 .clock_set
= sgi_clock_set
,
764 .clock_get
= sgi_clock_get
,
765 .timer_create
= sgi_timer_create
,
766 .nsleep
= do_posix_clock_nonanosleep
,
767 .timer_set
= sgi_timer_set
,
768 .timer_del
= sgi_timer_del
,
769 .timer_get
= sgi_timer_get
773 * mmtimer_init - device initialization routine
775 * Does initial setup for the mmtimer device.
777 static int __init
mmtimer_init(void)
779 cnodeid_t node
, maxn
= -1;
781 if (!ia64_platform_is("sn2"))
785 * Sanity check the cycles/sec variable
787 if (sn_rtc_cycles_per_second
< 100000) {
788 printk(KERN_ERR
"%s: unable to determine clock frequency\n",
793 mmtimer_femtoperiod
= ((unsigned long)1E15
+ sn_rtc_cycles_per_second
/
794 2) / sn_rtc_cycles_per_second
;
796 if (request_irq(SGI_MMTIMER_VECTOR
, mmtimer_interrupt
, IRQF_PERCPU
, MMTIMER_NAME
, NULL
)) {
797 printk(KERN_WARNING
"%s: unable to allocate interrupt.",
802 if (misc_register(&mmtimer_miscdev
)) {
803 printk(KERN_ERR
"%s: failed to register device\n",
808 /* Get max numbered node, calculate slots needed */
809 for_each_online_node(node
) {
814 /* Allocate list of node ptrs to mmtimer_t's */
815 timers
= kzalloc(sizeof(struct mmtimer_node
)*maxn
, GFP_KERNEL
);
816 if (timers
== NULL
) {
817 printk(KERN_ERR
"%s: failed to allocate memory for device\n",
822 /* Initialize struct mmtimer's for each online node */
823 for_each_online_node(node
) {
824 spin_lock_init(&timers
[node
].lock
);
825 tasklet_init(&timers
[node
].tasklet
, mmtimer_tasklet
,
826 (unsigned long) node
);
829 sgi_clock_period
= sgi_clock
.res
= NSEC_PER_SEC
/ sn_rtc_cycles_per_second
;
830 register_posix_clock(CLOCK_SGI_CYCLE
, &sgi_clock
);
832 printk(KERN_INFO
"%s: v%s, %ld MHz\n", MMTIMER_DESC
, MMTIMER_VERSION
,
833 sn_rtc_cycles_per_second
/(unsigned long)1E6
);
839 misc_deregister(&mmtimer_miscdev
);
841 free_irq(SGI_MMTIMER_VECTOR
, NULL
);
846 module_init(mmtimer_init
);