2 * Intel & MS High Precision Event Timer Implementation.
4 * Copyright (C) 2003 Intel Corporation
6 * (c) Copyright 2004 Hewlett-Packard Development Company, L.P.
7 * Bob Picco <robert.picco@hp.com>
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License version 2 as
11 * published by the Free Software Foundation.
14 #include <linux/interrupt.h>
15 #include <linux/module.h>
16 #include <linux/kernel.h>
17 #include <linux/smp_lock.h>
18 #include <linux/types.h>
19 #include <linux/miscdevice.h>
20 #include <linux/major.h>
21 #include <linux/ioport.h>
22 #include <linux/fcntl.h>
23 #include <linux/init.h>
24 #include <linux/poll.h>
26 #include <linux/proc_fs.h>
27 #include <linux/spinlock.h>
28 #include <linux/sysctl.h>
29 #include <linux/wait.h>
30 #include <linux/bcd.h>
31 #include <linux/seq_file.h>
32 #include <linux/bitops.h>
33 #include <linux/clocksource.h>
35 #include <asm/current.h>
36 #include <asm/uaccess.h>
37 #include <asm/system.h>
40 #include <asm/div64.h>
42 #include <linux/acpi.h>
43 #include <acpi/acpi_bus.h>
44 #include <linux/hpet.h>
47 * The High Precision Event Timer driver.
48 * This driver is closely modelled after the rtc.c driver.
49 * http://www.intel.com/hardwaredesign/hpetspec.htm
51 #define HPET_USER_FREQ (64)
52 #define HPET_DRIFT (500)
54 #define HPET_RANGE_SIZE 1024 /* from HPET spec */
57 /* WARNING -- don't get confused. These macros are never used
58 * to write the (single) counter, and rarely to read it.
59 * They're badly named; to fix, someday.
61 #if BITS_PER_LONG == 64
62 #define write_counter(V, MC) writeq(V, MC)
63 #define read_counter(MC) readq(MC)
65 #define write_counter(V, MC) writel(V, MC)
66 #define read_counter(MC) readl(MC)
69 static u32 hpet_nhpet
, hpet_max_freq
= HPET_USER_FREQ
;
71 /* This clocksource driver currently only works on ia64 */
73 static void __iomem
*hpet_mctr
;
75 static cycle_t
read_hpet(void)
77 return (cycle_t
)read_counter((void __iomem
*)hpet_mctr
);
80 static struct clocksource clocksource_hpet
= {
84 .mask
= CLOCKSOURCE_MASK(64),
85 .mult
= 0, /* to be calculated */
87 .flags
= CLOCK_SOURCE_IS_CONTINUOUS
,
89 static struct clocksource
*hpet_clocksource
;
92 /* A lock for concurrent access by app and isr hpet activity. */
93 static DEFINE_SPINLOCK(hpet_lock
);
95 #define HPET_DEV_NAME (7)
98 struct hpets
*hd_hpets
;
99 struct hpet __iomem
*hd_hpet
;
100 struct hpet_timer __iomem
*hd_timer
;
101 unsigned long hd_ireqfreq
;
102 unsigned long hd_irqdata
;
103 wait_queue_head_t hd_waitqueue
;
104 struct fasync_struct
*hd_async_queue
;
105 unsigned int hd_flags
;
107 unsigned int hd_hdwirq
;
108 char hd_name
[HPET_DEV_NAME
];
112 struct hpets
*hp_next
;
113 struct hpet __iomem
*hp_hpet
;
114 unsigned long hp_hpet_phys
;
115 struct clocksource
*hp_clocksource
;
116 unsigned long long hp_tick_freq
;
117 unsigned long hp_delta
;
118 unsigned int hp_ntimer
;
119 unsigned int hp_which
;
120 struct hpet_dev hp_dev
[1];
123 static struct hpets
*hpets
;
125 #define HPET_OPEN 0x0001
126 #define HPET_IE 0x0002 /* interrupt enabled */
127 #define HPET_PERIODIC 0x0004
128 #define HPET_SHARED_IRQ 0x0008
132 static inline unsigned long long readq(void __iomem
*addr
)
134 return readl(addr
) | (((unsigned long long)readl(addr
+ 4)) << 32LL);
139 static inline void writeq(unsigned long long v
, void __iomem
*addr
)
141 writel(v
& 0xffffffff, addr
);
142 writel(v
>> 32, addr
+ 4);
146 static irqreturn_t
hpet_interrupt(int irq
, void *data
)
148 struct hpet_dev
*devp
;
152 isr
= 1 << (devp
- devp
->hd_hpets
->hp_dev
);
154 if ((devp
->hd_flags
& HPET_SHARED_IRQ
) &&
155 !(isr
& readl(&devp
->hd_hpet
->hpet_isr
)))
158 spin_lock(&hpet_lock
);
162 * For non-periodic timers, increment the accumulator.
163 * This has the effect of treating non-periodic like periodic.
165 if ((devp
->hd_flags
& (HPET_IE
| HPET_PERIODIC
)) == HPET_IE
) {
168 t
= devp
->hd_ireqfreq
;
169 m
= read_counter(&devp
->hd_hpet
->hpet_mc
);
170 write_counter(t
+ m
+ devp
->hd_hpets
->hp_delta
,
171 &devp
->hd_timer
->hpet_compare
);
174 if (devp
->hd_flags
& HPET_SHARED_IRQ
)
175 writel(isr
, &devp
->hd_hpet
->hpet_isr
);
176 spin_unlock(&hpet_lock
);
178 wake_up_interruptible(&devp
->hd_waitqueue
);
180 kill_fasync(&devp
->hd_async_queue
, SIGIO
, POLL_IN
);
185 static void hpet_timer_set_irq(struct hpet_dev
*devp
)
189 struct hpet_timer __iomem
*timer
;
191 spin_lock_irq(&hpet_lock
);
192 if (devp
->hd_hdwirq
) {
193 spin_unlock_irq(&hpet_lock
);
197 timer
= devp
->hd_timer
;
199 /* we prefer level triggered mode */
200 v
= readl(&timer
->hpet_config
);
201 if (!(v
& Tn_INT_TYPE_CNF_MASK
)) {
202 v
|= Tn_INT_TYPE_CNF_MASK
;
203 writel(v
, &timer
->hpet_config
);
205 spin_unlock_irq(&hpet_lock
);
207 v
= (readq(&timer
->hpet_config
) & Tn_INT_ROUTE_CAP_MASK
) >>
208 Tn_INT_ROUTE_CAP_SHIFT
;
211 * In PIC mode, skip IRQ0-4, IRQ6-9, IRQ12-15 which is always used by
212 * legacy device. In IO APIC mode, we skip all the legacy IRQS.
214 if (acpi_irq_model
== ACPI_IRQ_MODEL_PIC
)
219 for (irq
= find_first_bit(&v
, HPET_MAX_IRQ
); irq
< HPET_MAX_IRQ
;
220 irq
= find_next_bit(&v
, HPET_MAX_IRQ
, 1 + irq
)) {
222 if (irq
>= NR_IRQS
) {
227 gsi
= acpi_register_gsi(irq
, ACPI_LEVEL_SENSITIVE
,
232 /* FIXME: Setup interrupt source table */
235 if (irq
< HPET_MAX_IRQ
) {
236 spin_lock_irq(&hpet_lock
);
237 v
= readl(&timer
->hpet_config
);
238 v
|= irq
<< Tn_INT_ROUTE_CNF_SHIFT
;
239 writel(v
, &timer
->hpet_config
);
240 devp
->hd_hdwirq
= gsi
;
241 spin_unlock_irq(&hpet_lock
);
246 static int hpet_open(struct inode
*inode
, struct file
*file
)
248 struct hpet_dev
*devp
;
252 if (file
->f_mode
& FMODE_WRITE
)
256 spin_lock_irq(&hpet_lock
);
258 for (devp
= NULL
, hpetp
= hpets
; hpetp
&& !devp
; hpetp
= hpetp
->hp_next
)
259 for (i
= 0; i
< hpetp
->hp_ntimer
; i
++)
260 if (hpetp
->hp_dev
[i
].hd_flags
& HPET_OPEN
)
263 devp
= &hpetp
->hp_dev
[i
];
268 spin_unlock_irq(&hpet_lock
);
273 file
->private_data
= devp
;
274 devp
->hd_irqdata
= 0;
275 devp
->hd_flags
|= HPET_OPEN
;
276 spin_unlock_irq(&hpet_lock
);
279 hpet_timer_set_irq(devp
);
285 hpet_read(struct file
*file
, char __user
*buf
, size_t count
, loff_t
* ppos
)
287 DECLARE_WAITQUEUE(wait
, current
);
290 struct hpet_dev
*devp
;
292 devp
= file
->private_data
;
293 if (!devp
->hd_ireqfreq
)
296 if (count
< sizeof(unsigned long))
299 add_wait_queue(&devp
->hd_waitqueue
, &wait
);
302 set_current_state(TASK_INTERRUPTIBLE
);
304 spin_lock_irq(&hpet_lock
);
305 data
= devp
->hd_irqdata
;
306 devp
->hd_irqdata
= 0;
307 spin_unlock_irq(&hpet_lock
);
311 else if (file
->f_flags
& O_NONBLOCK
) {
314 } else if (signal_pending(current
)) {
315 retval
= -ERESTARTSYS
;
321 retval
= put_user(data
, (unsigned long __user
*)buf
);
323 retval
= sizeof(unsigned long);
325 __set_current_state(TASK_RUNNING
);
326 remove_wait_queue(&devp
->hd_waitqueue
, &wait
);
331 static unsigned int hpet_poll(struct file
*file
, poll_table
* wait
)
334 struct hpet_dev
*devp
;
336 devp
= file
->private_data
;
338 if (!devp
->hd_ireqfreq
)
341 poll_wait(file
, &devp
->hd_waitqueue
, wait
);
343 spin_lock_irq(&hpet_lock
);
344 v
= devp
->hd_irqdata
;
345 spin_unlock_irq(&hpet_lock
);
348 return POLLIN
| POLLRDNORM
;
353 static int hpet_mmap(struct file
*file
, struct vm_area_struct
*vma
)
355 #ifdef CONFIG_HPET_MMAP
356 struct hpet_dev
*devp
;
359 if (((vma
->vm_end
- vma
->vm_start
) != PAGE_SIZE
) || vma
->vm_pgoff
)
362 devp
= file
->private_data
;
363 addr
= devp
->hd_hpets
->hp_hpet_phys
;
365 if (addr
& (PAGE_SIZE
- 1))
368 vma
->vm_flags
|= VM_IO
;
369 vma
->vm_page_prot
= pgprot_noncached(vma
->vm_page_prot
);
371 if (io_remap_pfn_range(vma
, vma
->vm_start
, addr
>> PAGE_SHIFT
,
372 PAGE_SIZE
, vma
->vm_page_prot
)) {
373 printk(KERN_ERR
"%s: io_remap_pfn_range failed\n",
384 static int hpet_fasync(int fd
, struct file
*file
, int on
)
386 struct hpet_dev
*devp
;
388 devp
= file
->private_data
;
390 if (fasync_helper(fd
, file
, on
, &devp
->hd_async_queue
) >= 0)
396 static int hpet_release(struct inode
*inode
, struct file
*file
)
398 struct hpet_dev
*devp
;
399 struct hpet_timer __iomem
*timer
;
402 devp
= file
->private_data
;
403 timer
= devp
->hd_timer
;
405 spin_lock_irq(&hpet_lock
);
407 writeq((readq(&timer
->hpet_config
) & ~Tn_INT_ENB_CNF_MASK
),
408 &timer
->hpet_config
);
413 devp
->hd_ireqfreq
= 0;
415 if (devp
->hd_flags
& HPET_PERIODIC
416 && readq(&timer
->hpet_config
) & Tn_TYPE_CNF_MASK
) {
419 v
= readq(&timer
->hpet_config
);
420 v
^= Tn_TYPE_CNF_MASK
;
421 writeq(v
, &timer
->hpet_config
);
424 devp
->hd_flags
&= ~(HPET_OPEN
| HPET_IE
| HPET_PERIODIC
);
425 spin_unlock_irq(&hpet_lock
);
430 if (file
->f_flags
& FASYNC
)
431 hpet_fasync(-1, file
, 0);
433 file
->private_data
= NULL
;
437 static int hpet_ioctl_common(struct hpet_dev
*, int, unsigned long, int);
440 hpet_ioctl(struct inode
*inode
, struct file
*file
, unsigned int cmd
,
443 struct hpet_dev
*devp
;
445 devp
= file
->private_data
;
446 return hpet_ioctl_common(devp
, cmd
, arg
, 0);
449 static int hpet_ioctl_ieon(struct hpet_dev
*devp
)
451 struct hpet_timer __iomem
*timer
;
452 struct hpet __iomem
*hpet
;
455 unsigned long g
, v
, t
, m
;
456 unsigned long flags
, isr
;
458 timer
= devp
->hd_timer
;
459 hpet
= devp
->hd_hpet
;
460 hpetp
= devp
->hd_hpets
;
462 if (!devp
->hd_ireqfreq
)
465 spin_lock_irq(&hpet_lock
);
467 if (devp
->hd_flags
& HPET_IE
) {
468 spin_unlock_irq(&hpet_lock
);
472 devp
->hd_flags
|= HPET_IE
;
474 if (readl(&timer
->hpet_config
) & Tn_INT_TYPE_CNF_MASK
)
475 devp
->hd_flags
|= HPET_SHARED_IRQ
;
476 spin_unlock_irq(&hpet_lock
);
478 irq
= devp
->hd_hdwirq
;
481 unsigned long irq_flags
;
483 sprintf(devp
->hd_name
, "hpet%d", (int)(devp
- hpetp
->hp_dev
));
484 irq_flags
= devp
->hd_flags
& HPET_SHARED_IRQ
485 ? IRQF_SHARED
: IRQF_DISABLED
;
486 if (request_irq(irq
, hpet_interrupt
, irq_flags
,
487 devp
->hd_name
, (void *)devp
)) {
488 printk(KERN_ERR
"hpet: IRQ %d is not free\n", irq
);
494 spin_lock_irq(&hpet_lock
);
495 devp
->hd_flags
^= HPET_IE
;
496 spin_unlock_irq(&hpet_lock
);
501 t
= devp
->hd_ireqfreq
;
502 v
= readq(&timer
->hpet_config
);
504 /* 64-bit comparators are not yet supported through the ioctls,
505 * so force this into 32-bit mode if it supports both modes
507 g
= v
| Tn_32MODE_CNF_MASK
| Tn_INT_ENB_CNF_MASK
;
509 if (devp
->hd_flags
& HPET_PERIODIC
) {
510 write_counter(t
, &timer
->hpet_compare
);
511 g
|= Tn_TYPE_CNF_MASK
;
512 v
|= Tn_TYPE_CNF_MASK
;
513 writeq(v
, &timer
->hpet_config
);
514 v
|= Tn_VAL_SET_CNF_MASK
;
515 writeq(v
, &timer
->hpet_config
);
516 local_irq_save(flags
);
518 /* NOTE: what we modify here is a hidden accumulator
519 * register supported by periodic-capable comparators.
520 * We never want to modify the (single) counter; that
521 * would affect all the comparators.
523 m
= read_counter(&hpet
->hpet_mc
);
524 write_counter(t
+ m
+ hpetp
->hp_delta
, &timer
->hpet_compare
);
526 local_irq_save(flags
);
527 m
= read_counter(&hpet
->hpet_mc
);
528 write_counter(t
+ m
+ hpetp
->hp_delta
, &timer
->hpet_compare
);
531 if (devp
->hd_flags
& HPET_SHARED_IRQ
) {
532 isr
= 1 << (devp
- devp
->hd_hpets
->hp_dev
);
533 writel(isr
, &hpet
->hpet_isr
);
535 writeq(g
, &timer
->hpet_config
);
536 local_irq_restore(flags
);
541 /* converts Hz to number of timer ticks */
542 static inline unsigned long hpet_time_div(struct hpets
*hpets
,
545 unsigned long long m
;
547 m
= hpets
->hp_tick_freq
+ (dis
>> 1);
549 return (unsigned long)m
;
553 hpet_ioctl_common(struct hpet_dev
*devp
, int cmd
, unsigned long arg
, int kernel
)
555 struct hpet_timer __iomem
*timer
;
556 struct hpet __iomem
*hpet
;
567 timer
= devp
->hd_timer
;
568 hpet
= devp
->hd_hpet
;
569 hpetp
= devp
->hd_hpets
;
572 return hpet_ioctl_ieon(devp
);
581 if ((devp
->hd_flags
& HPET_IE
) == 0)
583 v
= readq(&timer
->hpet_config
);
584 v
&= ~Tn_INT_ENB_CNF_MASK
;
585 writeq(v
, &timer
->hpet_config
);
587 free_irq(devp
->hd_irq
, devp
);
590 devp
->hd_flags
^= HPET_IE
;
594 struct hpet_info info
;
596 if (devp
->hd_ireqfreq
)
598 hpet_time_div(hpetp
, devp
->hd_ireqfreq
);
600 info
.hi_ireqfreq
= 0;
602 readq(&timer
->hpet_config
) & Tn_PER_INT_CAP_MASK
;
603 info
.hi_hpet
= hpetp
->hp_which
;
604 info
.hi_timer
= devp
- hpetp
->hp_dev
;
606 memcpy((void *)arg
, &info
, sizeof(info
));
608 if (copy_to_user((void __user
*)arg
, &info
,
614 v
= readq(&timer
->hpet_config
);
615 if ((v
& Tn_PER_INT_CAP_MASK
) == 0) {
619 devp
->hd_flags
|= HPET_PERIODIC
;
622 v
= readq(&timer
->hpet_config
);
623 if ((v
& Tn_PER_INT_CAP_MASK
) == 0) {
627 if (devp
->hd_flags
& HPET_PERIODIC
&&
628 readq(&timer
->hpet_config
) & Tn_TYPE_CNF_MASK
) {
629 v
= readq(&timer
->hpet_config
);
630 v
^= Tn_TYPE_CNF_MASK
;
631 writeq(v
, &timer
->hpet_config
);
633 devp
->hd_flags
&= ~HPET_PERIODIC
;
636 if (!kernel
&& (arg
> hpet_max_freq
) &&
637 !capable(CAP_SYS_RESOURCE
)) {
647 devp
->hd_ireqfreq
= hpet_time_div(hpetp
, arg
);
653 static const struct file_operations hpet_fops
= {
654 .owner
= THIS_MODULE
,
660 .release
= hpet_release
,
661 .fasync
= hpet_fasync
,
665 static int hpet_is_known(struct hpet_data
*hdp
)
669 for (hpetp
= hpets
; hpetp
; hpetp
= hpetp
->hp_next
)
670 if (hpetp
->hp_hpet_phys
== hdp
->hd_phys_address
)
676 static ctl_table hpet_table
[] = {
678 .ctl_name
= CTL_UNNUMBERED
,
679 .procname
= "max-user-freq",
680 .data
= &hpet_max_freq
,
681 .maxlen
= sizeof(int),
683 .proc_handler
= &proc_dointvec
,
688 static ctl_table hpet_root
[] = {
690 .ctl_name
= CTL_UNNUMBERED
,
699 static ctl_table dev_root
[] = {
710 static struct ctl_table_header
*sysctl_header
;
713 * Adjustment for when arming the timer with
714 * initial conditions. That is, main counter
715 * ticks expired before interrupts are enabled.
717 #define TICK_CALIBRATE (1000UL)
719 static unsigned long hpet_calibrate(struct hpets
*hpetp
)
721 struct hpet_timer __iomem
*timer
= NULL
;
722 unsigned long t
, m
, count
, i
, flags
, start
;
723 struct hpet_dev
*devp
;
725 struct hpet __iomem
*hpet
;
727 for (j
= 0, devp
= hpetp
->hp_dev
; j
< hpetp
->hp_ntimer
; j
++, devp
++)
728 if ((devp
->hd_flags
& HPET_OPEN
) == 0) {
729 timer
= devp
->hd_timer
;
736 hpet
= hpetp
->hp_hpet
;
737 t
= read_counter(&timer
->hpet_compare
);
740 count
= hpet_time_div(hpetp
, TICK_CALIBRATE
);
742 local_irq_save(flags
);
744 start
= read_counter(&hpet
->hpet_mc
);
747 m
= read_counter(&hpet
->hpet_mc
);
748 write_counter(t
+ m
+ hpetp
->hp_delta
, &timer
->hpet_compare
);
749 } while (i
++, (m
- start
) < count
);
751 local_irq_restore(flags
);
753 return (m
- start
) / i
;
756 int hpet_alloc(struct hpet_data
*hdp
)
759 struct hpet_dev
*devp
;
763 struct hpet __iomem
*hpet
;
764 static struct hpets
*last
= NULL
;
765 unsigned long period
;
766 unsigned long long temp
;
769 * hpet_alloc can be called by platform dependent code.
770 * If platform dependent code has allocated the hpet that
771 * ACPI has also reported, then we catch it here.
773 if (hpet_is_known(hdp
)) {
774 printk(KERN_DEBUG
"%s: duplicate HPET ignored\n",
779 siz
= sizeof(struct hpets
) + ((hdp
->hd_nirqs
- 1) *
780 sizeof(struct hpet_dev
));
782 hpetp
= kzalloc(siz
, GFP_KERNEL
);
787 hpetp
->hp_which
= hpet_nhpet
++;
788 hpetp
->hp_hpet
= hdp
->hd_address
;
789 hpetp
->hp_hpet_phys
= hdp
->hd_phys_address
;
791 hpetp
->hp_ntimer
= hdp
->hd_nirqs
;
793 for (i
= 0; i
< hdp
->hd_nirqs
; i
++)
794 hpetp
->hp_dev
[i
].hd_hdwirq
= hdp
->hd_irq
[i
];
796 hpet
= hpetp
->hp_hpet
;
798 cap
= readq(&hpet
->hpet_cap
);
800 ntimer
= ((cap
& HPET_NUM_TIM_CAP_MASK
) >> HPET_NUM_TIM_CAP_SHIFT
) + 1;
802 if (hpetp
->hp_ntimer
!= ntimer
) {
803 printk(KERN_WARNING
"hpet: number irqs doesn't agree"
804 " with number of timers\n");
810 last
->hp_next
= hpetp
;
816 period
= (cap
& HPET_COUNTER_CLK_PERIOD_MASK
) >>
817 HPET_COUNTER_CLK_PERIOD_SHIFT
; /* fs, 10^-15 */
818 temp
= 1000000000000000uLL; /* 10^15 femtoseconds per second */
819 temp
+= period
>> 1; /* round */
820 do_div(temp
, period
);
821 hpetp
->hp_tick_freq
= temp
; /* ticks per second */
823 printk(KERN_INFO
"hpet%d: at MMIO 0x%lx, IRQ%s",
824 hpetp
->hp_which
, hdp
->hd_phys_address
,
825 hpetp
->hp_ntimer
> 1 ? "s" : "");
826 for (i
= 0; i
< hpetp
->hp_ntimer
; i
++)
827 printk("%s %d", i
> 0 ? "," : "", hdp
->hd_irq
[i
]);
831 "hpet%u: %u comparators, %d-bit %u.%06u MHz counter\n",
832 hpetp
->hp_which
, hpetp
->hp_ntimer
,
833 cap
& HPET_COUNTER_SIZE_MASK
? 64 : 32,
834 (unsigned) (hpetp
->hp_tick_freq
/ 1000000),
835 (unsigned) (hpetp
->hp_tick_freq
% 1000000));
837 mcfg
= readq(&hpet
->hpet_config
);
838 if ((mcfg
& HPET_ENABLE_CNF_MASK
) == 0) {
839 write_counter(0L, &hpet
->hpet_mc
);
840 mcfg
|= HPET_ENABLE_CNF_MASK
;
841 writeq(mcfg
, &hpet
->hpet_config
);
844 for (i
= 0, devp
= hpetp
->hp_dev
; i
< hpetp
->hp_ntimer
; i
++, devp
++) {
845 struct hpet_timer __iomem
*timer
;
847 timer
= &hpet
->hpet_timers
[devp
- hpetp
->hp_dev
];
849 devp
->hd_hpets
= hpetp
;
850 devp
->hd_hpet
= hpet
;
851 devp
->hd_timer
= timer
;
854 * If the timer was reserved by platform code,
855 * then make timer unavailable for opens.
857 if (hdp
->hd_state
& (1 << i
)) {
858 devp
->hd_flags
= HPET_OPEN
;
862 init_waitqueue_head(&devp
->hd_waitqueue
);
865 hpetp
->hp_delta
= hpet_calibrate(hpetp
);
867 /* This clocksource driver currently only works on ia64 */
869 if (!hpet_clocksource
) {
870 hpet_mctr
= (void __iomem
*)&hpetp
->hp_hpet
->hpet_mc
;
871 CLKSRC_FSYS_MMIO_SET(clocksource_hpet
.fsys_mmio
, hpet_mctr
);
872 clocksource_hpet
.mult
= clocksource_hz2mult(hpetp
->hp_tick_freq
,
873 clocksource_hpet
.shift
);
874 clocksource_register(&clocksource_hpet
);
875 hpetp
->hp_clocksource
= &clocksource_hpet
;
876 hpet_clocksource
= &clocksource_hpet
;
883 static acpi_status
hpet_resources(struct acpi_resource
*res
, void *data
)
885 struct hpet_data
*hdp
;
887 struct acpi_resource_address64 addr
;
891 status
= acpi_resource_to_address64(res
, &addr
);
893 if (ACPI_SUCCESS(status
)) {
894 hdp
->hd_phys_address
= addr
.minimum
;
895 hdp
->hd_address
= ioremap(addr
.minimum
, addr
.address_length
);
897 if (hpet_is_known(hdp
)) {
898 printk(KERN_DEBUG
"%s: 0x%lx is busy\n",
899 __func__
, hdp
->hd_phys_address
);
900 iounmap(hdp
->hd_address
);
901 return AE_ALREADY_EXISTS
;
903 } else if (res
->type
== ACPI_RESOURCE_TYPE_FIXED_MEMORY32
) {
904 struct acpi_resource_fixed_memory32
*fixmem32
;
906 fixmem32
= &res
->data
.fixed_memory32
;
910 hdp
->hd_phys_address
= fixmem32
->address
;
911 hdp
->hd_address
= ioremap(fixmem32
->address
,
914 if (hpet_is_known(hdp
)) {
915 printk(KERN_DEBUG
"%s: 0x%lx is busy\n",
916 __func__
, hdp
->hd_phys_address
);
917 iounmap(hdp
->hd_address
);
918 return AE_ALREADY_EXISTS
;
920 } else if (res
->type
== ACPI_RESOURCE_TYPE_EXTENDED_IRQ
) {
921 struct acpi_resource_extended_irq
*irqp
;
924 irqp
= &res
->data
.extended_irq
;
926 for (i
= 0; i
< irqp
->interrupt_count
; i
++) {
927 irq
= acpi_register_gsi(irqp
->interrupts
[i
],
928 irqp
->triggering
, irqp
->polarity
);
932 hdp
->hd_irq
[hdp
->hd_nirqs
] = irq
;
940 static int hpet_acpi_add(struct acpi_device
*device
)
943 struct hpet_data data
;
945 memset(&data
, 0, sizeof(data
));
948 acpi_walk_resources(device
->handle
, METHOD_NAME__CRS
,
949 hpet_resources
, &data
);
951 if (ACPI_FAILURE(result
))
954 if (!data
.hd_address
|| !data
.hd_nirqs
) {
955 printk("%s: no address or irqs in _CRS\n", __func__
);
959 return hpet_alloc(&data
);
962 static int hpet_acpi_remove(struct acpi_device
*device
, int type
)
964 /* XXX need to unregister clocksource, dealloc mem, etc */
968 static const struct acpi_device_id hpet_device_ids
[] = {
972 MODULE_DEVICE_TABLE(acpi
, hpet_device_ids
);
974 static struct acpi_driver hpet_acpi_driver
= {
976 .ids
= hpet_device_ids
,
978 .add
= hpet_acpi_add
,
979 .remove
= hpet_acpi_remove
,
983 static struct miscdevice hpet_misc
= { HPET_MINOR
, "hpet", &hpet_fops
};
985 static int __init
hpet_init(void)
989 result
= misc_register(&hpet_misc
);
993 sysctl_header
= register_sysctl_table(dev_root
);
995 result
= acpi_bus_register_driver(&hpet_acpi_driver
);
998 unregister_sysctl_table(sysctl_header
);
999 misc_deregister(&hpet_misc
);
1006 static void __exit
hpet_exit(void)
1008 acpi_bus_unregister_driver(&hpet_acpi_driver
);
1011 unregister_sysctl_table(sysctl_header
);
1012 misc_deregister(&hpet_misc
);
1017 module_init(hpet_init
);
1018 module_exit(hpet_exit
);
1019 MODULE_AUTHOR("Bob Picco <Robert.Picco@hp.com>");
1020 MODULE_LICENSE("GPL");