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/compat.h>
34 #include <linux/clocksource.h>
35 #include <linux/slab.h>
37 #include <asm/current.h>
38 #include <asm/uaccess.h>
39 #include <asm/system.h>
42 #include <asm/div64.h>
44 #include <linux/acpi.h>
45 #include <acpi/acpi_bus.h>
46 #include <linux/hpet.h>
49 * The High Precision Event Timer driver.
50 * This driver is closely modelled after the rtc.c driver.
51 * http://www.intel.com/hardwaredesign/hpetspec_1.pdf
53 #define HPET_USER_FREQ (64)
54 #define HPET_DRIFT (500)
56 #define HPET_RANGE_SIZE 1024 /* from HPET spec */
59 /* WARNING -- don't get confused. These macros are never used
60 * to write the (single) counter, and rarely to read it.
61 * They're badly named; to fix, someday.
63 #if BITS_PER_LONG == 64
64 #define write_counter(V, MC) writeq(V, MC)
65 #define read_counter(MC) readq(MC)
67 #define write_counter(V, MC) writel(V, MC)
68 #define read_counter(MC) readl(MC)
71 static DEFINE_MUTEX(hpet_mutex
); /* replaces BKL */
72 static u32 hpet_nhpet
, hpet_max_freq
= HPET_USER_FREQ
;
74 /* This clocksource driver currently only works on ia64 */
76 static void __iomem
*hpet_mctr
;
78 static cycle_t
read_hpet(struct clocksource
*cs
)
80 return (cycle_t
)read_counter((void __iomem
*)hpet_mctr
);
83 static struct clocksource clocksource_hpet
= {
87 .mask
= CLOCKSOURCE_MASK(64),
88 .mult
= 0, /* to be calculated */
90 .flags
= CLOCK_SOURCE_IS_CONTINUOUS
,
92 static struct clocksource
*hpet_clocksource
;
95 /* A lock for concurrent access by app and isr hpet activity. */
96 static DEFINE_SPINLOCK(hpet_lock
);
98 #define HPET_DEV_NAME (7)
101 struct hpets
*hd_hpets
;
102 struct hpet __iomem
*hd_hpet
;
103 struct hpet_timer __iomem
*hd_timer
;
104 unsigned long hd_ireqfreq
;
105 unsigned long hd_irqdata
;
106 wait_queue_head_t hd_waitqueue
;
107 struct fasync_struct
*hd_async_queue
;
108 unsigned int hd_flags
;
110 unsigned int hd_hdwirq
;
111 char hd_name
[HPET_DEV_NAME
];
115 struct hpets
*hp_next
;
116 struct hpet __iomem
*hp_hpet
;
117 unsigned long hp_hpet_phys
;
118 struct clocksource
*hp_clocksource
;
119 unsigned long long hp_tick_freq
;
120 unsigned long hp_delta
;
121 unsigned int hp_ntimer
;
122 unsigned int hp_which
;
123 struct hpet_dev hp_dev
[1];
126 static struct hpets
*hpets
;
128 #define HPET_OPEN 0x0001
129 #define HPET_IE 0x0002 /* interrupt enabled */
130 #define HPET_PERIODIC 0x0004
131 #define HPET_SHARED_IRQ 0x0008
135 static inline unsigned long long readq(void __iomem
*addr
)
137 return readl(addr
) | (((unsigned long long)readl(addr
+ 4)) << 32LL);
142 static inline void writeq(unsigned long long v
, void __iomem
*addr
)
144 writel(v
& 0xffffffff, addr
);
145 writel(v
>> 32, addr
+ 4);
149 static irqreturn_t
hpet_interrupt(int irq
, void *data
)
151 struct hpet_dev
*devp
;
155 isr
= 1 << (devp
- devp
->hd_hpets
->hp_dev
);
157 if ((devp
->hd_flags
& HPET_SHARED_IRQ
) &&
158 !(isr
& readl(&devp
->hd_hpet
->hpet_isr
)))
161 spin_lock(&hpet_lock
);
165 * For non-periodic timers, increment the accumulator.
166 * This has the effect of treating non-periodic like periodic.
168 if ((devp
->hd_flags
& (HPET_IE
| HPET_PERIODIC
)) == HPET_IE
) {
171 t
= devp
->hd_ireqfreq
;
172 m
= read_counter(&devp
->hd_timer
->hpet_compare
);
173 write_counter(t
+ m
, &devp
->hd_timer
->hpet_compare
);
176 if (devp
->hd_flags
& HPET_SHARED_IRQ
)
177 writel(isr
, &devp
->hd_hpet
->hpet_isr
);
178 spin_unlock(&hpet_lock
);
180 wake_up_interruptible(&devp
->hd_waitqueue
);
182 kill_fasync(&devp
->hd_async_queue
, SIGIO
, POLL_IN
);
187 static void hpet_timer_set_irq(struct hpet_dev
*devp
)
191 struct hpet_timer __iomem
*timer
;
193 spin_lock_irq(&hpet_lock
);
194 if (devp
->hd_hdwirq
) {
195 spin_unlock_irq(&hpet_lock
);
199 timer
= devp
->hd_timer
;
201 /* we prefer level triggered mode */
202 v
= readl(&timer
->hpet_config
);
203 if (!(v
& Tn_INT_TYPE_CNF_MASK
)) {
204 v
|= Tn_INT_TYPE_CNF_MASK
;
205 writel(v
, &timer
->hpet_config
);
207 spin_unlock_irq(&hpet_lock
);
209 v
= (readq(&timer
->hpet_config
) & Tn_INT_ROUTE_CAP_MASK
) >>
210 Tn_INT_ROUTE_CAP_SHIFT
;
213 * In PIC mode, skip IRQ0-4, IRQ6-9, IRQ12-15 which is always used by
214 * legacy device. In IO APIC mode, we skip all the legacy IRQS.
216 if (acpi_irq_model
== ACPI_IRQ_MODEL_PIC
)
221 for_each_set_bit(irq
, &v
, HPET_MAX_IRQ
) {
222 if (irq
>= nr_irqs
) {
227 gsi
= acpi_register_gsi(NULL
, 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
)
255 mutex_lock(&hpet_mutex
);
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
);
269 mutex_unlock(&hpet_mutex
);
273 file
->private_data
= devp
;
274 devp
->hd_irqdata
= 0;
275 devp
->hd_flags
|= HPET_OPEN
;
276 spin_unlock_irq(&hpet_lock
);
277 mutex_unlock(&hpet_mutex
);
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 file
->private_data
= NULL
;
434 static int hpet_ioctl_ieon(struct hpet_dev
*devp
)
436 struct hpet_timer __iomem
*timer
;
437 struct hpet __iomem
*hpet
;
440 unsigned long g
, v
, t
, m
;
441 unsigned long flags
, isr
;
443 timer
= devp
->hd_timer
;
444 hpet
= devp
->hd_hpet
;
445 hpetp
= devp
->hd_hpets
;
447 if (!devp
->hd_ireqfreq
)
450 spin_lock_irq(&hpet_lock
);
452 if (devp
->hd_flags
& HPET_IE
) {
453 spin_unlock_irq(&hpet_lock
);
457 devp
->hd_flags
|= HPET_IE
;
459 if (readl(&timer
->hpet_config
) & Tn_INT_TYPE_CNF_MASK
)
460 devp
->hd_flags
|= HPET_SHARED_IRQ
;
461 spin_unlock_irq(&hpet_lock
);
463 irq
= devp
->hd_hdwirq
;
466 unsigned long irq_flags
;
468 sprintf(devp
->hd_name
, "hpet%d", (int)(devp
- hpetp
->hp_dev
));
469 irq_flags
= devp
->hd_flags
& HPET_SHARED_IRQ
470 ? IRQF_SHARED
: IRQF_DISABLED
;
471 if (request_irq(irq
, hpet_interrupt
, irq_flags
,
472 devp
->hd_name
, (void *)devp
)) {
473 printk(KERN_ERR
"hpet: IRQ %d is not free\n", irq
);
479 spin_lock_irq(&hpet_lock
);
480 devp
->hd_flags
^= HPET_IE
;
481 spin_unlock_irq(&hpet_lock
);
486 t
= devp
->hd_ireqfreq
;
487 v
= readq(&timer
->hpet_config
);
489 /* 64-bit comparators are not yet supported through the ioctls,
490 * so force this into 32-bit mode if it supports both modes
492 g
= v
| Tn_32MODE_CNF_MASK
| Tn_INT_ENB_CNF_MASK
;
494 if (devp
->hd_flags
& HPET_PERIODIC
) {
495 g
|= Tn_TYPE_CNF_MASK
;
496 v
|= Tn_TYPE_CNF_MASK
| Tn_VAL_SET_CNF_MASK
;
497 writeq(v
, &timer
->hpet_config
);
498 local_irq_save(flags
);
501 * NOTE: First we modify the hidden accumulator
502 * register supported by periodic-capable comparators.
503 * We never want to modify the (single) counter; that
504 * would affect all the comparators. The value written
505 * is the counter value when the first interrupt is due.
507 m
= read_counter(&hpet
->hpet_mc
);
508 write_counter(t
+ m
+ hpetp
->hp_delta
, &timer
->hpet_compare
);
510 * Then we modify the comparator, indicating the period
511 * for subsequent interrupt.
513 write_counter(t
, &timer
->hpet_compare
);
515 local_irq_save(flags
);
516 m
= read_counter(&hpet
->hpet_mc
);
517 write_counter(t
+ m
+ hpetp
->hp_delta
, &timer
->hpet_compare
);
520 if (devp
->hd_flags
& HPET_SHARED_IRQ
) {
521 isr
= 1 << (devp
- devp
->hd_hpets
->hp_dev
);
522 writel(isr
, &hpet
->hpet_isr
);
524 writeq(g
, &timer
->hpet_config
);
525 local_irq_restore(flags
);
530 /* converts Hz to number of timer ticks */
531 static inline unsigned long hpet_time_div(struct hpets
*hpets
,
534 unsigned long long m
;
536 m
= hpets
->hp_tick_freq
+ (dis
>> 1);
538 return (unsigned long)m
;
542 hpet_ioctl_common(struct hpet_dev
*devp
, int cmd
, unsigned long arg
,
543 struct hpet_info
*info
)
545 struct hpet_timer __iomem
*timer
;
546 struct hpet __iomem
*hpet
;
557 timer
= devp
->hd_timer
;
558 hpet
= devp
->hd_hpet
;
559 hpetp
= devp
->hd_hpets
;
562 return hpet_ioctl_ieon(devp
);
571 if ((devp
->hd_flags
& HPET_IE
) == 0)
573 v
= readq(&timer
->hpet_config
);
574 v
&= ~Tn_INT_ENB_CNF_MASK
;
575 writeq(v
, &timer
->hpet_config
);
577 free_irq(devp
->hd_irq
, devp
);
580 devp
->hd_flags
^= HPET_IE
;
584 if (devp
->hd_ireqfreq
)
586 hpet_time_div(hpetp
, devp
->hd_ireqfreq
);
588 info
->hi_ireqfreq
= 0;
590 readq(&timer
->hpet_config
) & Tn_PER_INT_CAP_MASK
;
591 info
->hi_hpet
= hpetp
->hp_which
;
592 info
->hi_timer
= devp
- hpetp
->hp_dev
;
596 v
= readq(&timer
->hpet_config
);
597 if ((v
& Tn_PER_INT_CAP_MASK
) == 0) {
601 devp
->hd_flags
|= HPET_PERIODIC
;
604 v
= readq(&timer
->hpet_config
);
605 if ((v
& Tn_PER_INT_CAP_MASK
) == 0) {
609 if (devp
->hd_flags
& HPET_PERIODIC
&&
610 readq(&timer
->hpet_config
) & Tn_TYPE_CNF_MASK
) {
611 v
= readq(&timer
->hpet_config
);
612 v
^= Tn_TYPE_CNF_MASK
;
613 writeq(v
, &timer
->hpet_config
);
615 devp
->hd_flags
&= ~HPET_PERIODIC
;
618 if ((arg
> hpet_max_freq
) &&
619 !capable(CAP_SYS_RESOURCE
)) {
629 devp
->hd_ireqfreq
= hpet_time_div(hpetp
, arg
);
636 hpet_ioctl(struct file
*file
, unsigned int cmd
, unsigned long arg
)
638 struct hpet_info info
;
641 mutex_lock(&hpet_mutex
);
642 err
= hpet_ioctl_common(file
->private_data
, cmd
, arg
, &info
);
643 mutex_unlock(&hpet_mutex
);
645 if ((cmd
== HPET_INFO
) && !err
&&
646 (copy_to_user((void __user
*)arg
, &info
, sizeof(info
))))
653 struct compat_hpet_info
{
654 compat_ulong_t hi_ireqfreq
; /* Hz */
655 compat_ulong_t hi_flags
; /* information */
656 unsigned short hi_hpet
;
657 unsigned short hi_timer
;
661 hpet_compat_ioctl(struct file
*file
, unsigned int cmd
, unsigned long arg
)
663 struct hpet_info info
;
666 mutex_lock(&hpet_mutex
);
667 err
= hpet_ioctl_common(file
->private_data
, cmd
, arg
, &info
);
668 mutex_unlock(&hpet_mutex
);
670 if ((cmd
== HPET_INFO
) && !err
) {
671 struct compat_hpet_info __user
*u
= compat_ptr(arg
);
672 if (put_user(info
.hi_ireqfreq
, &u
->hi_ireqfreq
) ||
673 put_user(info
.hi_flags
, &u
->hi_flags
) ||
674 put_user(info
.hi_hpet
, &u
->hi_hpet
) ||
675 put_user(info
.hi_timer
, &u
->hi_timer
))
683 static const struct file_operations hpet_fops
= {
684 .owner
= THIS_MODULE
,
688 .unlocked_ioctl
= hpet_ioctl
,
690 .compat_ioctl
= hpet_compat_ioctl
,
693 .release
= hpet_release
,
694 .fasync
= hpet_fasync
,
698 static int hpet_is_known(struct hpet_data
*hdp
)
702 for (hpetp
= hpets
; hpetp
; hpetp
= hpetp
->hp_next
)
703 if (hpetp
->hp_hpet_phys
== hdp
->hd_phys_address
)
709 static ctl_table hpet_table
[] = {
711 .procname
= "max-user-freq",
712 .data
= &hpet_max_freq
,
713 .maxlen
= sizeof(int),
715 .proc_handler
= proc_dointvec
,
720 static ctl_table hpet_root
[] = {
730 static ctl_table dev_root
[] = {
740 static struct ctl_table_header
*sysctl_header
;
743 * Adjustment for when arming the timer with
744 * initial conditions. That is, main counter
745 * ticks expired before interrupts are enabled.
747 #define TICK_CALIBRATE (1000UL)
749 static unsigned long __hpet_calibrate(struct hpets
*hpetp
)
751 struct hpet_timer __iomem
*timer
= NULL
;
752 unsigned long t
, m
, count
, i
, flags
, start
;
753 struct hpet_dev
*devp
;
755 struct hpet __iomem
*hpet
;
757 for (j
= 0, devp
= hpetp
->hp_dev
; j
< hpetp
->hp_ntimer
; j
++, devp
++)
758 if ((devp
->hd_flags
& HPET_OPEN
) == 0) {
759 timer
= devp
->hd_timer
;
766 hpet
= hpetp
->hp_hpet
;
767 t
= read_counter(&timer
->hpet_compare
);
770 count
= hpet_time_div(hpetp
, TICK_CALIBRATE
);
772 local_irq_save(flags
);
774 start
= read_counter(&hpet
->hpet_mc
);
777 m
= read_counter(&hpet
->hpet_mc
);
778 write_counter(t
+ m
+ hpetp
->hp_delta
, &timer
->hpet_compare
);
779 } while (i
++, (m
- start
) < count
);
781 local_irq_restore(flags
);
783 return (m
- start
) / i
;
786 static unsigned long hpet_calibrate(struct hpets
*hpetp
)
788 unsigned long ret
= -1;
792 * Try to calibrate until return value becomes stable small value.
793 * If SMI interruption occurs in calibration loop, the return value
794 * will be big. This avoids its impact.
797 tmp
= __hpet_calibrate(hpetp
);
806 int hpet_alloc(struct hpet_data
*hdp
)
809 struct hpet_dev
*devp
;
813 struct hpet __iomem
*hpet
;
814 static struct hpets
*last
= NULL
;
815 unsigned long period
;
816 unsigned long long temp
;
820 * hpet_alloc can be called by platform dependent code.
821 * If platform dependent code has allocated the hpet that
822 * ACPI has also reported, then we catch it here.
824 if (hpet_is_known(hdp
)) {
825 printk(KERN_DEBUG
"%s: duplicate HPET ignored\n",
830 siz
= sizeof(struct hpets
) + ((hdp
->hd_nirqs
- 1) *
831 sizeof(struct hpet_dev
));
833 hpetp
= kzalloc(siz
, GFP_KERNEL
);
838 hpetp
->hp_which
= hpet_nhpet
++;
839 hpetp
->hp_hpet
= hdp
->hd_address
;
840 hpetp
->hp_hpet_phys
= hdp
->hd_phys_address
;
842 hpetp
->hp_ntimer
= hdp
->hd_nirqs
;
844 for (i
= 0; i
< hdp
->hd_nirqs
; i
++)
845 hpetp
->hp_dev
[i
].hd_hdwirq
= hdp
->hd_irq
[i
];
847 hpet
= hpetp
->hp_hpet
;
849 cap
= readq(&hpet
->hpet_cap
);
851 ntimer
= ((cap
& HPET_NUM_TIM_CAP_MASK
) >> HPET_NUM_TIM_CAP_SHIFT
) + 1;
853 if (hpetp
->hp_ntimer
!= ntimer
) {
854 printk(KERN_WARNING
"hpet: number irqs doesn't agree"
855 " with number of timers\n");
861 last
->hp_next
= hpetp
;
867 period
= (cap
& HPET_COUNTER_CLK_PERIOD_MASK
) >>
868 HPET_COUNTER_CLK_PERIOD_SHIFT
; /* fs, 10^-15 */
869 temp
= 1000000000000000uLL; /* 10^15 femtoseconds per second */
870 temp
+= period
>> 1; /* round */
871 do_div(temp
, period
);
872 hpetp
->hp_tick_freq
= temp
; /* ticks per second */
874 printk(KERN_INFO
"hpet%d: at MMIO 0x%lx, IRQ%s",
875 hpetp
->hp_which
, hdp
->hd_phys_address
,
876 hpetp
->hp_ntimer
> 1 ? "s" : "");
877 for (i
= 0; i
< hpetp
->hp_ntimer
; i
++)
878 printk("%s %d", i
> 0 ? "," : "", hdp
->hd_irq
[i
]);
881 temp
= hpetp
->hp_tick_freq
;
882 remainder
= do_div(temp
, 1000000);
884 "hpet%u: %u comparators, %d-bit %u.%06u MHz counter\n",
885 hpetp
->hp_which
, hpetp
->hp_ntimer
,
886 cap
& HPET_COUNTER_SIZE_MASK
? 64 : 32,
887 (unsigned) temp
, remainder
);
889 mcfg
= readq(&hpet
->hpet_config
);
890 if ((mcfg
& HPET_ENABLE_CNF_MASK
) == 0) {
891 write_counter(0L, &hpet
->hpet_mc
);
892 mcfg
|= HPET_ENABLE_CNF_MASK
;
893 writeq(mcfg
, &hpet
->hpet_config
);
896 for (i
= 0, devp
= hpetp
->hp_dev
; i
< hpetp
->hp_ntimer
; i
++, devp
++) {
897 struct hpet_timer __iomem
*timer
;
899 timer
= &hpet
->hpet_timers
[devp
- hpetp
->hp_dev
];
901 devp
->hd_hpets
= hpetp
;
902 devp
->hd_hpet
= hpet
;
903 devp
->hd_timer
= timer
;
906 * If the timer was reserved by platform code,
907 * then make timer unavailable for opens.
909 if (hdp
->hd_state
& (1 << i
)) {
910 devp
->hd_flags
= HPET_OPEN
;
914 init_waitqueue_head(&devp
->hd_waitqueue
);
917 hpetp
->hp_delta
= hpet_calibrate(hpetp
);
919 /* This clocksource driver currently only works on ia64 */
921 if (!hpet_clocksource
) {
922 hpet_mctr
= (void __iomem
*)&hpetp
->hp_hpet
->hpet_mc
;
923 CLKSRC_FSYS_MMIO_SET(clocksource_hpet
.fsys_mmio
, hpet_mctr
);
924 clocksource_hpet
.mult
= clocksource_hz2mult(hpetp
->hp_tick_freq
,
925 clocksource_hpet
.shift
);
926 clocksource_register(&clocksource_hpet
);
927 hpetp
->hp_clocksource
= &clocksource_hpet
;
928 hpet_clocksource
= &clocksource_hpet
;
935 static acpi_status
hpet_resources(struct acpi_resource
*res
, void *data
)
937 struct hpet_data
*hdp
;
939 struct acpi_resource_address64 addr
;
943 status
= acpi_resource_to_address64(res
, &addr
);
945 if (ACPI_SUCCESS(status
)) {
946 hdp
->hd_phys_address
= addr
.minimum
;
947 hdp
->hd_address
= ioremap(addr
.minimum
, addr
.address_length
);
949 if (hpet_is_known(hdp
)) {
950 iounmap(hdp
->hd_address
);
951 return AE_ALREADY_EXISTS
;
953 } else if (res
->type
== ACPI_RESOURCE_TYPE_FIXED_MEMORY32
) {
954 struct acpi_resource_fixed_memory32
*fixmem32
;
956 fixmem32
= &res
->data
.fixed_memory32
;
960 hdp
->hd_phys_address
= fixmem32
->address
;
961 hdp
->hd_address
= ioremap(fixmem32
->address
,
964 if (hpet_is_known(hdp
)) {
965 iounmap(hdp
->hd_address
);
966 return AE_ALREADY_EXISTS
;
968 } else if (res
->type
== ACPI_RESOURCE_TYPE_EXTENDED_IRQ
) {
969 struct acpi_resource_extended_irq
*irqp
;
972 irqp
= &res
->data
.extended_irq
;
974 for (i
= 0; i
< irqp
->interrupt_count
; i
++) {
975 irq
= acpi_register_gsi(NULL
, irqp
->interrupts
[i
],
976 irqp
->triggering
, irqp
->polarity
);
980 hdp
->hd_irq
[hdp
->hd_nirqs
] = irq
;
988 static int hpet_acpi_add(struct acpi_device
*device
)
991 struct hpet_data data
;
993 memset(&data
, 0, sizeof(data
));
996 acpi_walk_resources(device
->handle
, METHOD_NAME__CRS
,
997 hpet_resources
, &data
);
999 if (ACPI_FAILURE(result
))
1002 if (!data
.hd_address
|| !data
.hd_nirqs
) {
1003 printk("%s: no address or irqs in _CRS\n", __func__
);
1007 return hpet_alloc(&data
);
1010 static int hpet_acpi_remove(struct acpi_device
*device
, int type
)
1012 /* XXX need to unregister clocksource, dealloc mem, etc */
1016 static const struct acpi_device_id hpet_device_ids
[] = {
1020 MODULE_DEVICE_TABLE(acpi
, hpet_device_ids
);
1022 static struct acpi_driver hpet_acpi_driver
= {
1024 .ids
= hpet_device_ids
,
1026 .add
= hpet_acpi_add
,
1027 .remove
= hpet_acpi_remove
,
1031 static struct miscdevice hpet_misc
= { HPET_MINOR
, "hpet", &hpet_fops
};
1033 static int __init
hpet_init(void)
1037 result
= misc_register(&hpet_misc
);
1041 sysctl_header
= register_sysctl_table(dev_root
);
1043 result
= acpi_bus_register_driver(&hpet_acpi_driver
);
1046 unregister_sysctl_table(sysctl_header
);
1047 misc_deregister(&hpet_misc
);
1054 static void __exit
hpet_exit(void)
1056 acpi_bus_unregister_driver(&hpet_acpi_driver
);
1059 unregister_sysctl_table(sysctl_header
);
1060 misc_deregister(&hpet_misc
);
1065 module_init(hpet_init
);
1066 module_exit(hpet_exit
);
1067 MODULE_AUTHOR("Bob Picco <Robert.Picco@hp.com>");
1068 MODULE_LICENSE("GPL");