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
,
76 .llseek
= noop_llseek
,
80 * We only have comparison registers RTC1-4 currently available per
81 * node. RTC0 is used by SAL.
83 /* Check for an RTC interrupt pending */
84 static int mmtimer_int_pending(int comparator
)
86 if (HUB_L((unsigned long *)LOCAL_MMR_ADDR(SH_EVENT_OCCURRED
)) &
87 SH_EVENT_OCCURRED_RTC1_INT_MASK
<< comparator
)
93 /* Clear the RTC interrupt pending bit */
94 static void mmtimer_clr_int_pending(int comparator
)
96 HUB_S((u64
*)LOCAL_MMR_ADDR(SH_EVENT_OCCURRED_ALIAS
),
97 SH_EVENT_OCCURRED_RTC1_INT_MASK
<< comparator
);
100 /* Setup timer on comparator RTC1 */
101 static void mmtimer_setup_int_0(int cpu
, u64 expires
)
105 /* Disable interrupt */
106 HUB_S((u64
*)LOCAL_MMR_ADDR(SH_RTC1_INT_ENABLE
), 0UL);
108 /* Initialize comparator value */
109 HUB_S((u64
*)LOCAL_MMR_ADDR(SH_INT_CMPB
), -1L);
111 /* Clear pending bit */
112 mmtimer_clr_int_pending(0);
114 val
= ((u64
)SGI_MMTIMER_VECTOR
<< SH_RTC1_INT_CONFIG_IDX_SHFT
) |
115 ((u64
)cpu_physical_id(cpu
) <<
116 SH_RTC1_INT_CONFIG_PID_SHFT
);
118 /* Set configuration */
119 HUB_S((u64
*)LOCAL_MMR_ADDR(SH_RTC1_INT_CONFIG
), val
);
121 /* Enable RTC interrupts */
122 HUB_S((u64
*)LOCAL_MMR_ADDR(SH_RTC1_INT_ENABLE
), 1UL);
124 /* Initialize comparator value */
125 HUB_S((u64
*)LOCAL_MMR_ADDR(SH_INT_CMPB
), expires
);
130 /* Setup timer on comparator RTC2 */
131 static void mmtimer_setup_int_1(int cpu
, u64 expires
)
135 HUB_S((u64
*)LOCAL_MMR_ADDR(SH_RTC2_INT_ENABLE
), 0UL);
137 HUB_S((u64
*)LOCAL_MMR_ADDR(SH_INT_CMPC
), -1L);
139 mmtimer_clr_int_pending(1);
141 val
= ((u64
)SGI_MMTIMER_VECTOR
<< SH_RTC2_INT_CONFIG_IDX_SHFT
) |
142 ((u64
)cpu_physical_id(cpu
) <<
143 SH_RTC2_INT_CONFIG_PID_SHFT
);
145 HUB_S((u64
*)LOCAL_MMR_ADDR(SH_RTC2_INT_CONFIG
), val
);
147 HUB_S((u64
*)LOCAL_MMR_ADDR(SH_RTC2_INT_ENABLE
), 1UL);
149 HUB_S((u64
*)LOCAL_MMR_ADDR(SH_INT_CMPC
), expires
);
152 /* Setup timer on comparator RTC3 */
153 static void mmtimer_setup_int_2(int cpu
, u64 expires
)
157 HUB_S((u64
*)LOCAL_MMR_ADDR(SH_RTC3_INT_ENABLE
), 0UL);
159 HUB_S((u64
*)LOCAL_MMR_ADDR(SH_INT_CMPD
), -1L);
161 mmtimer_clr_int_pending(2);
163 val
= ((u64
)SGI_MMTIMER_VECTOR
<< SH_RTC3_INT_CONFIG_IDX_SHFT
) |
164 ((u64
)cpu_physical_id(cpu
) <<
165 SH_RTC3_INT_CONFIG_PID_SHFT
);
167 HUB_S((u64
*)LOCAL_MMR_ADDR(SH_RTC3_INT_CONFIG
), val
);
169 HUB_S((u64
*)LOCAL_MMR_ADDR(SH_RTC3_INT_ENABLE
), 1UL);
171 HUB_S((u64
*)LOCAL_MMR_ADDR(SH_INT_CMPD
), expires
);
175 * This function must be called with interrupts disabled and preemption off
176 * in order to insure that the setup succeeds in a deterministic time frame.
177 * It will check if the interrupt setup succeeded.
179 static int mmtimer_setup(int cpu
, int comparator
, unsigned long expires
)
182 switch (comparator
) {
184 mmtimer_setup_int_0(cpu
, expires
);
187 mmtimer_setup_int_1(cpu
, expires
);
190 mmtimer_setup_int_2(cpu
, expires
);
193 /* We might've missed our expiration time */
194 if (rtc_time() <= expires
)
198 * If an interrupt is already pending then its okay
199 * if not then we failed
201 return mmtimer_int_pending(comparator
);
204 static int mmtimer_disable_int(long nasid
, int comparator
)
206 switch (comparator
) {
208 nasid
== -1 ? HUB_S((u64
*)LOCAL_MMR_ADDR(SH_RTC1_INT_ENABLE
),
209 0UL) : REMOTE_HUB_S(nasid
, SH_RTC1_INT_ENABLE
, 0UL);
212 nasid
== -1 ? HUB_S((u64
*)LOCAL_MMR_ADDR(SH_RTC2_INT_ENABLE
),
213 0UL) : REMOTE_HUB_S(nasid
, SH_RTC2_INT_ENABLE
, 0UL);
216 nasid
== -1 ? HUB_S((u64
*)LOCAL_MMR_ADDR(SH_RTC3_INT_ENABLE
),
217 0UL) : REMOTE_HUB_S(nasid
, SH_RTC3_INT_ENABLE
, 0UL);
225 #define COMPARATOR 1 /* The comparator to use */
227 #define TIMER_OFF 0xbadcabLL /* Timer is not setup */
228 #define TIMER_SET 0 /* Comparator is set for this timer */
230 /* There is one of these for each timer */
233 struct k_itimer
*timer
;
237 struct mmtimer_node
{
238 spinlock_t lock ____cacheline_aligned
;
239 struct rb_root timer_head
;
240 struct rb_node
*next
;
241 struct tasklet_struct tasklet
;
243 static struct mmtimer_node
*timers
;
247 * Add a new mmtimer struct to the node's mmtimer list.
248 * This function assumes the struct mmtimer_node is locked.
250 static void mmtimer_add_list(struct mmtimer
*n
)
252 int nodeid
= n
->timer
->it
.mmtimer
.node
;
253 unsigned long expires
= n
->timer
->it
.mmtimer
.expires
;
254 struct rb_node
**link
= &timers
[nodeid
].timer_head
.rb_node
;
255 struct rb_node
*parent
= NULL
;
259 * Find the right place in the rbtree:
263 x
= rb_entry(parent
, struct mmtimer
, list
);
265 if (expires
< x
->timer
->it
.mmtimer
.expires
)
266 link
= &(*link
)->rb_left
;
268 link
= &(*link
)->rb_right
;
272 * Insert the timer to the rbtree and check whether it
273 * replaces the first pending timer
275 rb_link_node(&n
->list
, parent
, link
);
276 rb_insert_color(&n
->list
, &timers
[nodeid
].timer_head
);
278 if (!timers
[nodeid
].next
|| expires
< rb_entry(timers
[nodeid
].next
,
279 struct mmtimer
, list
)->timer
->it
.mmtimer
.expires
)
280 timers
[nodeid
].next
= &n
->list
;
284 * Set the comparator for the next timer.
285 * This function assumes the struct mmtimer_node is locked.
287 static void mmtimer_set_next_timer(int nodeid
)
289 struct mmtimer_node
*n
= &timers
[nodeid
];
298 x
= rb_entry(n
->next
, struct mmtimer
, list
);
300 if (!t
->it
.mmtimer
.incr
) {
301 /* Not an interval timer */
302 if (!mmtimer_setup(x
->cpu
, COMPARATOR
,
303 t
->it
.mmtimer
.expires
)) {
304 /* Late setup, fire now */
305 tasklet_schedule(&n
->tasklet
);
312 while (!mmtimer_setup(x
->cpu
, COMPARATOR
, t
->it
.mmtimer
.expires
)) {
314 struct rb_node
*next
;
315 t
->it
.mmtimer
.expires
+= t
->it
.mmtimer
.incr
<< o
;
316 t
->it_overrun
+= 1 << o
;
319 printk(KERN_ALERT
"mmtimer: cannot reschedule timer\n");
320 t
->it
.mmtimer
.clock
= TIMER_OFF
;
321 n
->next
= rb_next(&x
->list
);
322 rb_erase(&x
->list
, &n
->timer_head
);
327 e
= t
->it
.mmtimer
.expires
;
328 next
= rb_next(&x
->list
);
333 e1
= rb_entry(next
, struct mmtimer
, list
)->
334 timer
->it
.mmtimer
.expires
;
337 rb_erase(&x
->list
, &n
->timer_head
);
345 * mmtimer_ioctl - ioctl interface for /dev/mmtimer
346 * @file: file structure for the device
347 * @cmd: command to execute
348 * @arg: optional argument to command
350 * Executes the command specified by @cmd. Returns 0 for success, < 0 for
355 * %MMTIMER_GETOFFSET - Should return the offset (relative to the start
356 * of the page where the registers are mapped) for the counter in question.
358 * %MMTIMER_GETRES - Returns the resolution of the clock in femto (10^-15)
361 * %MMTIMER_GETFREQ - Copies the frequency of the clock in Hz to the address
364 * %MMTIMER_GETBITS - Returns the number of bits in the clock's counter
366 * %MMTIMER_MMAPAVAIL - Returns 1 if the registers can be mmap'd into userspace
368 * %MMTIMER_GETCOUNTER - Gets the current value in the counter and places it
369 * in the address specified by @arg.
371 static long mmtimer_ioctl(struct file
*file
, unsigned int cmd
,
376 mutex_lock(&mmtimer_mutex
);
379 case MMTIMER_GETOFFSET
: /* offset of the counter */
381 * SN RTC registers are on their own 64k page
383 if(PAGE_SIZE
<= (1 << 16))
384 ret
= (((long)RTC_COUNTER_ADDR
) & (PAGE_SIZE
-1)) / 8;
389 case MMTIMER_GETRES
: /* resolution of the clock in 10^-15 s */
390 if(copy_to_user((unsigned long __user
*)arg
,
391 &mmtimer_femtoperiod
, sizeof(unsigned long)))
395 case MMTIMER_GETFREQ
: /* frequency in Hz */
396 if(copy_to_user((unsigned long __user
*)arg
,
397 &sn_rtc_cycles_per_second
,
398 sizeof(unsigned long)))
402 case MMTIMER_GETBITS
: /* number of bits in the clock */
406 case MMTIMER_MMAPAVAIL
: /* can we mmap the clock into userspace? */
407 ret
= (PAGE_SIZE
<= (1 << 16)) ? 1 : 0;
410 case MMTIMER_GETCOUNTER
:
411 if(copy_to_user((unsigned long __user
*)arg
,
412 RTC_COUNTER_ADDR
, sizeof(unsigned long)))
419 mutex_unlock(&mmtimer_mutex
);
424 * mmtimer_mmap - maps the clock's registers into userspace
425 * @file: file structure for the device
426 * @vma: VMA to map the registers into
428 * Calls remap_pfn_range() to map the clock's registers into
429 * the calling process' address space.
431 static int mmtimer_mmap(struct file
*file
, struct vm_area_struct
*vma
)
433 unsigned long mmtimer_addr
;
435 if (vma
->vm_end
- vma
->vm_start
!= PAGE_SIZE
)
438 if (vma
->vm_flags
& VM_WRITE
)
441 if (PAGE_SIZE
> (1 << 16))
444 vma
->vm_page_prot
= pgprot_noncached(vma
->vm_page_prot
);
446 mmtimer_addr
= __pa(RTC_COUNTER_ADDR
);
447 mmtimer_addr
&= ~(PAGE_SIZE
- 1);
448 mmtimer_addr
&= 0xfffffffffffffffUL
;
450 if (remap_pfn_range(vma
, vma
->vm_start
, mmtimer_addr
>> PAGE_SHIFT
,
451 PAGE_SIZE
, vma
->vm_page_prot
)) {
452 printk(KERN_ERR
"remap_pfn_range failed in mmtimer.c\n");
459 static struct miscdevice mmtimer_miscdev
= {
465 static struct timespec sgi_clock_offset
;
466 static int sgi_clock_period
;
469 * Posix Timer Interface
472 static struct timespec sgi_clock_offset
;
473 static int sgi_clock_period
;
475 static int sgi_clock_get(clockid_t clockid
, struct timespec
*tp
)
479 nsec
= rtc_time() * sgi_clock_period
480 + sgi_clock_offset
.tv_nsec
;
481 *tp
= ns_to_timespec(nsec
);
482 tp
->tv_sec
+= sgi_clock_offset
.tv_sec
;
486 static int sgi_clock_set(clockid_t clockid
, struct timespec
*tp
)
492 nsec
= rtc_time() * sgi_clock_period
;
494 sgi_clock_offset
.tv_sec
= tp
->tv_sec
- div_u64_rem(nsec
, NSEC_PER_SEC
, &rem
);
496 if (rem
<= tp
->tv_nsec
)
497 sgi_clock_offset
.tv_nsec
= tp
->tv_sec
- rem
;
499 sgi_clock_offset
.tv_nsec
= tp
->tv_sec
+ NSEC_PER_SEC
- rem
;
500 sgi_clock_offset
.tv_sec
--;
506 * mmtimer_interrupt - timer interrupt handler
508 * @dev_id: device the irq came from
510 * Called when one of the comarators matches the counter, This
511 * routine will send signals to processes that have requested
514 * This interrupt is run in an interrupt context
515 * by the SHUB. It is therefore safe to locally access SHub
519 mmtimer_interrupt(int irq
, void *dev_id
)
521 unsigned long expires
= 0;
522 int result
= IRQ_NONE
;
523 unsigned indx
= cpu_to_node(smp_processor_id());
524 struct mmtimer
*base
;
526 spin_lock(&timers
[indx
].lock
);
527 base
= rb_entry(timers
[indx
].next
, struct mmtimer
, list
);
529 spin_unlock(&timers
[indx
].lock
);
533 if (base
->cpu
== smp_processor_id()) {
535 expires
= base
->timer
->it
.mmtimer
.expires
;
536 /* expires test won't work with shared irqs */
537 if ((mmtimer_int_pending(COMPARATOR
) > 0) ||
538 (expires
&& (expires
<= rtc_time()))) {
539 mmtimer_clr_int_pending(COMPARATOR
);
540 tasklet_schedule(&timers
[indx
].tasklet
);
541 result
= IRQ_HANDLED
;
544 spin_unlock(&timers
[indx
].lock
);
548 static void mmtimer_tasklet(unsigned long data
)
551 struct mmtimer_node
*mn
= &timers
[nodeid
];
556 /* Send signal and deal with periodic signals */
557 spin_lock_irqsave(&mn
->lock
, flags
);
561 x
= rb_entry(mn
->next
, struct mmtimer
, list
);
564 if (t
->it
.mmtimer
.clock
== TIMER_OFF
)
569 mn
->next
= rb_next(&x
->list
);
570 rb_erase(&x
->list
, &mn
->timer_head
);
572 if (posix_timer_event(t
, 0) != 0)
575 if(t
->it
.mmtimer
.incr
) {
576 t
->it
.mmtimer
.expires
+= t
->it
.mmtimer
.incr
;
579 /* Ensure we don't false trigger in mmtimer_interrupt */
580 t
->it
.mmtimer
.clock
= TIMER_OFF
;
581 t
->it
.mmtimer
.expires
= 0;
584 /* Set comparator for next timer, if there is one */
585 mmtimer_set_next_timer(nodeid
);
587 t
->it_overrun_last
= t
->it_overrun
;
589 spin_unlock_irqrestore(&mn
->lock
, flags
);
592 static int sgi_timer_create(struct k_itimer
*timer
)
594 /* Insure that a newly created timer is off */
595 timer
->it
.mmtimer
.clock
= TIMER_OFF
;
599 /* This does not really delete a timer. It just insures
600 * that the timer is not active
602 * Assumption: it_lock is already held with irq's disabled
604 static int sgi_timer_del(struct k_itimer
*timr
)
606 cnodeid_t nodeid
= timr
->it
.mmtimer
.node
;
607 unsigned long irqflags
;
609 spin_lock_irqsave(&timers
[nodeid
].lock
, irqflags
);
610 if (timr
->it
.mmtimer
.clock
!= TIMER_OFF
) {
611 unsigned long expires
= timr
->it
.mmtimer
.expires
;
612 struct rb_node
*n
= timers
[nodeid
].timer_head
.rb_node
;
613 struct mmtimer
*uninitialized_var(t
);
616 timr
->it
.mmtimer
.clock
= TIMER_OFF
;
617 timr
->it
.mmtimer
.expires
= 0;
620 t
= rb_entry(n
, struct mmtimer
, list
);
621 if (t
->timer
== timr
)
624 if (expires
< t
->timer
->it
.mmtimer
.expires
)
631 spin_unlock_irqrestore(&timers
[nodeid
].lock
, irqflags
);
635 if (timers
[nodeid
].next
== n
) {
636 timers
[nodeid
].next
= rb_next(n
);
640 rb_erase(n
, &timers
[nodeid
].timer_head
);
644 mmtimer_disable_int(cnodeid_to_nasid(nodeid
),
646 mmtimer_set_next_timer(nodeid
);
649 spin_unlock_irqrestore(&timers
[nodeid
].lock
, irqflags
);
653 /* Assumption: it_lock is already held with irq's disabled */
654 static void sgi_timer_get(struct k_itimer
*timr
, struct itimerspec
*cur_setting
)
657 if (timr
->it
.mmtimer
.clock
== TIMER_OFF
) {
658 cur_setting
->it_interval
.tv_nsec
= 0;
659 cur_setting
->it_interval
.tv_sec
= 0;
660 cur_setting
->it_value
.tv_nsec
= 0;
661 cur_setting
->it_value
.tv_sec
=0;
665 cur_setting
->it_interval
= ns_to_timespec(timr
->it
.mmtimer
.incr
* sgi_clock_period
);
666 cur_setting
->it_value
= ns_to_timespec((timr
->it
.mmtimer
.expires
- rtc_time()) * sgi_clock_period
);
670 static int sgi_timer_set(struct k_itimer
*timr
, int flags
,
671 struct itimerspec
* new_setting
,
672 struct itimerspec
* old_setting
)
674 unsigned long when
, period
, irqflags
;
677 struct mmtimer
*base
;
681 sgi_timer_get(timr
, old_setting
);
684 when
= timespec_to_ns(&new_setting
->it_value
);
685 period
= timespec_to_ns(&new_setting
->it_interval
);
691 base
= kmalloc(sizeof(struct mmtimer
), GFP_KERNEL
);
695 if (flags
& TIMER_ABSTIME
) {
700 now
= timespec_to_ns(&n
);
704 /* Fire the timer immediately */
709 * Convert to sgi clock period. Need to keep rtc_time() as near as possible
710 * to getnstimeofday() in order to be as faithful as possible to the time
713 when
= (when
+ sgi_clock_period
- 1) / sgi_clock_period
+ rtc_time();
714 period
= (period
+ sgi_clock_period
- 1) / sgi_clock_period
;
717 * We are allocating a local SHub comparator. If we would be moved to another
718 * cpu then another SHub may be local to us. Prohibit that by switching off
723 nodeid
= cpu_to_node(smp_processor_id());
725 /* Lock the node timer structure */
726 spin_lock_irqsave(&timers
[nodeid
].lock
, irqflags
);
729 base
->cpu
= smp_processor_id();
731 timr
->it
.mmtimer
.clock
= TIMER_SET
;
732 timr
->it
.mmtimer
.node
= nodeid
;
733 timr
->it
.mmtimer
.incr
= period
;
734 timr
->it
.mmtimer
.expires
= when
;
736 n
= timers
[nodeid
].next
;
738 /* Add the new struct mmtimer to node's timer list */
739 mmtimer_add_list(base
);
741 if (timers
[nodeid
].next
== n
) {
742 /* No need to reprogram comparator for now */
743 spin_unlock_irqrestore(&timers
[nodeid
].lock
, irqflags
);
748 /* We need to reprogram the comparator */
750 mmtimer_disable_int(cnodeid_to_nasid(nodeid
), COMPARATOR
);
752 mmtimer_set_next_timer(nodeid
);
754 /* Unlock the node timer structure */
755 spin_unlock_irqrestore(&timers
[nodeid
].lock
, irqflags
);
762 static struct k_clock sgi_clock
= {
764 .clock_set
= sgi_clock_set
,
765 .clock_get
= sgi_clock_get
,
766 .timer_create
= sgi_timer_create
,
767 .nsleep
= do_posix_clock_nonanosleep
,
768 .timer_set
= sgi_timer_set
,
769 .timer_del
= sgi_timer_del
,
770 .timer_get
= sgi_timer_get
774 * mmtimer_init - device initialization routine
776 * Does initial setup for the mmtimer device.
778 static int __init
mmtimer_init(void)
780 cnodeid_t node
, maxn
= -1;
782 if (!ia64_platform_is("sn2"))
786 * Sanity check the cycles/sec variable
788 if (sn_rtc_cycles_per_second
< 100000) {
789 printk(KERN_ERR
"%s: unable to determine clock frequency\n",
794 mmtimer_femtoperiod
= ((unsigned long)1E15
+ sn_rtc_cycles_per_second
/
795 2) / sn_rtc_cycles_per_second
;
797 if (request_irq(SGI_MMTIMER_VECTOR
, mmtimer_interrupt
, IRQF_PERCPU
, MMTIMER_NAME
, NULL
)) {
798 printk(KERN_WARNING
"%s: unable to allocate interrupt.",
803 if (misc_register(&mmtimer_miscdev
)) {
804 printk(KERN_ERR
"%s: failed to register device\n",
809 /* Get max numbered node, calculate slots needed */
810 for_each_online_node(node
) {
815 /* Allocate list of node ptrs to mmtimer_t's */
816 timers
= kzalloc(sizeof(struct mmtimer_node
)*maxn
, GFP_KERNEL
);
817 if (timers
== NULL
) {
818 printk(KERN_ERR
"%s: failed to allocate memory for device\n",
823 /* Initialize struct mmtimer's for each online node */
824 for_each_online_node(node
) {
825 spin_lock_init(&timers
[node
].lock
);
826 tasklet_init(&timers
[node
].tasklet
, mmtimer_tasklet
,
827 (unsigned long) node
);
830 sgi_clock_period
= sgi_clock
.res
= NSEC_PER_SEC
/ sn_rtc_cycles_per_second
;
831 register_posix_clock(CLOCK_SGI_CYCLE
, &sgi_clock
);
833 printk(KERN_INFO
"%s: v%s, %ld MHz\n", MMTIMER_DESC
, MMTIMER_VERSION
,
834 sn_rtc_cycles_per_second
/(unsigned long)1E6
);
840 misc_deregister(&mmtimer_miscdev
);
842 free_irq(SGI_MMTIMER_VECTOR
, NULL
);
847 module_init(mmtimer_init
);