blob: cf325622b396f31e4e14bec78538ad537aec60be [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * Intel & MS High Precision Event Timer Implementation.
3 *
4 * Copyright (C) 2003 Intel Corporation
5 * Venki Pallipadi
6 * (c) Copyright 2004 Hewlett-Packard Development Company, L.P.
7 * Bob Picco <robert.picco@hp.com>
8 *
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.
12 */
13
14#include <linux/config.h>
15#include <linux/interrupt.h>
16#include <linux/module.h>
17#include <linux/kernel.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>
25#include <linux/proc_fs.h>
26#include <linux/spinlock.h>
27#include <linux/sysctl.h>
28#include <linux/wait.h>
29#include <linux/bcd.h>
30#include <linux/seq_file.h>
31#include <linux/bitops.h>
32
33#include <asm/current.h>
34#include <asm/uaccess.h>
35#include <asm/system.h>
36#include <asm/io.h>
37#include <asm/irq.h>
38#include <asm/div64.h>
39
40#include <linux/acpi.h>
41#include <acpi/acpi_bus.h>
42#include <linux/hpet.h>
43
44/*
45 * The High Precision Event Timer driver.
46 * This driver is closely modelled after the rtc.c driver.
Alex Williamson96803822005-09-06 15:17:54 -070047 * http://www.intel.com/hardwaredesign/hpetspec.htm
Linus Torvalds1da177e2005-04-16 15:20:36 -070048 */
49#define HPET_USER_FREQ (64)
50#define HPET_DRIFT (500)
51
Clemens Ladisch642d30b2005-10-30 15:03:31 -080052static u32 hpet_nhpet, hpet_max_freq = HPET_USER_FREQ;
Linus Torvalds1da177e2005-04-16 15:20:36 -070053
54/* A lock for concurrent access by app and isr hpet activity. */
55static DEFINE_SPINLOCK(hpet_lock);
56/* A lock for concurrent intermodule access to hpet and isr hpet activity. */
57static DEFINE_SPINLOCK(hpet_task_lock);
58
59#define HPET_DEV_NAME (7)
60
61struct hpet_dev {
62 struct hpets *hd_hpets;
63 struct hpet __iomem *hd_hpet;
64 struct hpet_timer __iomem *hd_timer;
65 unsigned long hd_ireqfreq;
66 unsigned long hd_irqdata;
67 wait_queue_head_t hd_waitqueue;
68 struct fasync_struct *hd_async_queue;
69 struct hpet_task *hd_task;
70 unsigned int hd_flags;
71 unsigned int hd_irq;
72 unsigned int hd_hdwirq;
73 char hd_name[HPET_DEV_NAME];
74};
75
76struct hpets {
77 struct hpets *hp_next;
78 struct hpet __iomem *hp_hpet;
79 unsigned long hp_hpet_phys;
80 struct time_interpolator *hp_interpolator;
Clemens Ladischba3f2132005-10-30 15:03:31 -080081 unsigned long long hp_tick_freq;
Linus Torvalds1da177e2005-04-16 15:20:36 -070082 unsigned long hp_delta;
83 unsigned int hp_ntimer;
84 unsigned int hp_which;
85 struct hpet_dev hp_dev[1];
86};
87
88static struct hpets *hpets;
89
90#define HPET_OPEN 0x0001
91#define HPET_IE 0x0002 /* interrupt enabled */
92#define HPET_PERIODIC 0x0004
Clemens Ladisch0d290862005-10-30 15:03:34 -080093#define HPET_SHARED_IRQ 0x0008
Linus Torvalds1da177e2005-04-16 15:20:36 -070094
95#if BITS_PER_LONG == 64
96#define write_counter(V, MC) writeq(V, MC)
97#define read_counter(MC) readq(MC)
98#else
99#define write_counter(V, MC) writel(V, MC)
100#define read_counter(MC) readl(MC)
101#endif
102
103#ifndef readq
Adrian Bunk887c27f2005-09-10 00:26:52 -0700104static inline unsigned long long readq(void __iomem *addr)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700105{
106 return readl(addr) | (((unsigned long long)readl(addr + 4)) << 32LL);
107}
108#endif
109
110#ifndef writeq
Adrian Bunk887c27f2005-09-10 00:26:52 -0700111static inline void writeq(unsigned long long v, void __iomem *addr)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700112{
113 writel(v & 0xffffffff, addr);
114 writel(v >> 32, addr + 4);
115}
116#endif
117
118static irqreturn_t hpet_interrupt(int irq, void *data, struct pt_regs *regs)
119{
120 struct hpet_dev *devp;
121 unsigned long isr;
122
123 devp = data;
Clemens Ladisch0d290862005-10-30 15:03:34 -0800124 isr = 1 << (devp - devp->hd_hpets->hp_dev);
125
126 if ((devp->hd_flags & HPET_SHARED_IRQ) &&
127 !(isr & readl(&devp->hd_hpet->hpet_isr)))
128 return IRQ_NONE;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700129
130 spin_lock(&hpet_lock);
131 devp->hd_irqdata++;
132
133 /*
134 * For non-periodic timers, increment the accumulator.
135 * This has the effect of treating non-periodic like periodic.
136 */
137 if ((devp->hd_flags & (HPET_IE | HPET_PERIODIC)) == HPET_IE) {
138 unsigned long m, t;
139
140 t = devp->hd_ireqfreq;
141 m = read_counter(&devp->hd_hpet->hpet_mc);
142 write_counter(t + m + devp->hd_hpets->hp_delta,
143 &devp->hd_timer->hpet_compare);
144 }
145
Clemens Ladisch0d290862005-10-30 15:03:34 -0800146 if (devp->hd_flags & HPET_SHARED_IRQ)
147 writel(isr, &devp->hd_hpet->hpet_isr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700148 spin_unlock(&hpet_lock);
149
150 spin_lock(&hpet_task_lock);
151 if (devp->hd_task)
152 devp->hd_task->ht_func(devp->hd_task->ht_data);
153 spin_unlock(&hpet_task_lock);
154
155 wake_up_interruptible(&devp->hd_waitqueue);
156
157 kill_fasync(&devp->hd_async_queue, SIGIO, POLL_IN);
158
159 return IRQ_HANDLED;
160}
161
162static int hpet_open(struct inode *inode, struct file *file)
163{
164 struct hpet_dev *devp;
165 struct hpets *hpetp;
166 int i;
167
168 if (file->f_mode & FMODE_WRITE)
169 return -EINVAL;
170
171 spin_lock_irq(&hpet_lock);
172
173 for (devp = NULL, hpetp = hpets; hpetp && !devp; hpetp = hpetp->hp_next)
174 for (i = 0; i < hpetp->hp_ntimer; i++)
175 if (hpetp->hp_dev[i].hd_flags & HPET_OPEN
176 || hpetp->hp_dev[i].hd_task)
177 continue;
178 else {
179 devp = &hpetp->hp_dev[i];
180 break;
181 }
182
183 if (!devp) {
184 spin_unlock_irq(&hpet_lock);
185 return -EBUSY;
186 }
187
188 file->private_data = devp;
189 devp->hd_irqdata = 0;
190 devp->hd_flags |= HPET_OPEN;
191 spin_unlock_irq(&hpet_lock);
192
193 return 0;
194}
195
196static ssize_t
197hpet_read(struct file *file, char __user *buf, size_t count, loff_t * ppos)
198{
199 DECLARE_WAITQUEUE(wait, current);
200 unsigned long data;
201 ssize_t retval;
202 struct hpet_dev *devp;
203
204 devp = file->private_data;
205 if (!devp->hd_ireqfreq)
206 return -EIO;
207
208 if (count < sizeof(unsigned long))
209 return -EINVAL;
210
211 add_wait_queue(&devp->hd_waitqueue, &wait);
212
213 for ( ; ; ) {
214 set_current_state(TASK_INTERRUPTIBLE);
215
216 spin_lock_irq(&hpet_lock);
217 data = devp->hd_irqdata;
218 devp->hd_irqdata = 0;
219 spin_unlock_irq(&hpet_lock);
220
221 if (data)
222 break;
223 else if (file->f_flags & O_NONBLOCK) {
224 retval = -EAGAIN;
225 goto out;
226 } else if (signal_pending(current)) {
227 retval = -ERESTARTSYS;
228 goto out;
229 }
230 schedule();
231 }
232
233 retval = put_user(data, (unsigned long __user *)buf);
234 if (!retval)
235 retval = sizeof(unsigned long);
236out:
237 __set_current_state(TASK_RUNNING);
238 remove_wait_queue(&devp->hd_waitqueue, &wait);
239
240 return retval;
241}
242
243static unsigned int hpet_poll(struct file *file, poll_table * wait)
244{
245 unsigned long v;
246 struct hpet_dev *devp;
247
248 devp = file->private_data;
249
250 if (!devp->hd_ireqfreq)
251 return 0;
252
253 poll_wait(file, &devp->hd_waitqueue, wait);
254
255 spin_lock_irq(&hpet_lock);
256 v = devp->hd_irqdata;
257 spin_unlock_irq(&hpet_lock);
258
259 if (v != 0)
260 return POLLIN | POLLRDNORM;
261
262 return 0;
263}
264
265static int hpet_mmap(struct file *file, struct vm_area_struct *vma)
266{
267#ifdef CONFIG_HPET_MMAP
268 struct hpet_dev *devp;
269 unsigned long addr;
270
271 if (((vma->vm_end - vma->vm_start) != PAGE_SIZE) || vma->vm_pgoff)
272 return -EINVAL;
273
274 devp = file->private_data;
275 addr = devp->hd_hpets->hp_hpet_phys;
276
277 if (addr & (PAGE_SIZE - 1))
278 return -ENOSYS;
279
280 vma->vm_flags |= VM_IO;
281 vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700282
283 if (io_remap_pfn_range(vma, vma->vm_start, addr >> PAGE_SHIFT,
284 PAGE_SIZE, vma->vm_page_prot)) {
285 printk(KERN_ERR "remap_pfn_range failed in hpet.c\n");
286 return -EAGAIN;
287 }
288
289 return 0;
290#else
291 return -ENOSYS;
292#endif
293}
294
295static int hpet_fasync(int fd, struct file *file, int on)
296{
297 struct hpet_dev *devp;
298
299 devp = file->private_data;
300
301 if (fasync_helper(fd, file, on, &devp->hd_async_queue) >= 0)
302 return 0;
303 else
304 return -EIO;
305}
306
307static int hpet_release(struct inode *inode, struct file *file)
308{
309 struct hpet_dev *devp;
310 struct hpet_timer __iomem *timer;
311 int irq = 0;
312
313 devp = file->private_data;
314 timer = devp->hd_timer;
315
316 spin_lock_irq(&hpet_lock);
317
318 writeq((readq(&timer->hpet_config) & ~Tn_INT_ENB_CNF_MASK),
319 &timer->hpet_config);
320
321 irq = devp->hd_irq;
322 devp->hd_irq = 0;
323
324 devp->hd_ireqfreq = 0;
325
326 if (devp->hd_flags & HPET_PERIODIC
327 && readq(&timer->hpet_config) & Tn_TYPE_CNF_MASK) {
328 unsigned long v;
329
330 v = readq(&timer->hpet_config);
331 v ^= Tn_TYPE_CNF_MASK;
332 writeq(v, &timer->hpet_config);
333 }
334
335 devp->hd_flags &= ~(HPET_OPEN | HPET_IE | HPET_PERIODIC);
336 spin_unlock_irq(&hpet_lock);
337
338 if (irq)
339 free_irq(irq, devp);
340
341 if (file->f_flags & FASYNC)
342 hpet_fasync(-1, file, 0);
343
344 file->private_data = NULL;
345 return 0;
346}
347
348static int hpet_ioctl_common(struct hpet_dev *, int, unsigned long, int);
349
350static int
351hpet_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
352 unsigned long arg)
353{
354 struct hpet_dev *devp;
355
356 devp = file->private_data;
357 return hpet_ioctl_common(devp, cmd, arg, 0);
358}
359
360static int hpet_ioctl_ieon(struct hpet_dev *devp)
361{
362 struct hpet_timer __iomem *timer;
363 struct hpet __iomem *hpet;
364 struct hpets *hpetp;
365 int irq;
366 unsigned long g, v, t, m;
367 unsigned long flags, isr;
368
369 timer = devp->hd_timer;
370 hpet = devp->hd_hpet;
371 hpetp = devp->hd_hpets;
372
Clemens Ladisch9090e6d2005-10-30 15:03:29 -0800373 if (!devp->hd_ireqfreq)
374 return -EIO;
375
Linus Torvalds1da177e2005-04-16 15:20:36 -0700376 spin_lock_irq(&hpet_lock);
377
378 if (devp->hd_flags & HPET_IE) {
379 spin_unlock_irq(&hpet_lock);
380 return -EBUSY;
381 }
382
383 devp->hd_flags |= HPET_IE;
Clemens Ladisch0d290862005-10-30 15:03:34 -0800384
385 if (readl(&timer->hpet_config) & Tn_INT_TYPE_CNF_MASK)
386 devp->hd_flags |= HPET_SHARED_IRQ;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700387 spin_unlock_irq(&hpet_lock);
388
Linus Torvalds1da177e2005-04-16 15:20:36 -0700389 irq = devp->hd_hdwirq;
390
391 if (irq) {
Clemens Ladisch0d290862005-10-30 15:03:34 -0800392 unsigned long irq_flags;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700393
Clemens Ladisch0d290862005-10-30 15:03:34 -0800394 sprintf(devp->hd_name, "hpet%d", (int)(devp - hpetp->hp_dev));
395 irq_flags = devp->hd_flags & HPET_SHARED_IRQ
396 ? SA_SHIRQ : SA_INTERRUPT;
397 if (request_irq(irq, hpet_interrupt, irq_flags,
398 devp->hd_name, (void *)devp)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700399 printk(KERN_ERR "hpet: IRQ %d is not free\n", irq);
400 irq = 0;
401 }
402 }
403
404 if (irq == 0) {
405 spin_lock_irq(&hpet_lock);
406 devp->hd_flags ^= HPET_IE;
407 spin_unlock_irq(&hpet_lock);
408 return -EIO;
409 }
410
411 devp->hd_irq = irq;
412 t = devp->hd_ireqfreq;
413 v = readq(&timer->hpet_config);
414 g = v | Tn_INT_ENB_CNF_MASK;
415
416 if (devp->hd_flags & HPET_PERIODIC) {
417 write_counter(t, &timer->hpet_compare);
418 g |= Tn_TYPE_CNF_MASK;
419 v |= Tn_TYPE_CNF_MASK;
420 writeq(v, &timer->hpet_config);
421 v |= Tn_VAL_SET_CNF_MASK;
422 writeq(v, &timer->hpet_config);
423 local_irq_save(flags);
424 m = read_counter(&hpet->hpet_mc);
425 write_counter(t + m + hpetp->hp_delta, &timer->hpet_compare);
426 } else {
427 local_irq_save(flags);
428 m = read_counter(&hpet->hpet_mc);
429 write_counter(t + m + hpetp->hp_delta, &timer->hpet_compare);
430 }
431
Clemens Ladisch0d290862005-10-30 15:03:34 -0800432 if (devp->hd_flags & HPET_SHARED_IRQ) {
Clemens Ladisch3d5640d2005-10-30 15:03:39 -0800433 isr = 1 << (devp - devp->hd_hpets->hp_dev);
Clemens Ladisch0d290862005-10-30 15:03:34 -0800434 writel(isr, &hpet->hpet_isr);
435 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700436 writeq(g, &timer->hpet_config);
437 local_irq_restore(flags);
438
439 return 0;
440}
441
Clemens Ladischba3f2132005-10-30 15:03:31 -0800442/* converts Hz to number of timer ticks */
443static inline unsigned long hpet_time_div(struct hpets *hpets,
444 unsigned long dis)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700445{
Clemens Ladischba3f2132005-10-30 15:03:31 -0800446 unsigned long long m;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700447
Clemens Ladischba3f2132005-10-30 15:03:31 -0800448 m = hpets->hp_tick_freq + (dis >> 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700449 do_div(m, dis);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700450 return (unsigned long)m;
451}
452
453static int
454hpet_ioctl_common(struct hpet_dev *devp, int cmd, unsigned long arg, int kernel)
455{
456 struct hpet_timer __iomem *timer;
457 struct hpet __iomem *hpet;
458 struct hpets *hpetp;
459 int err;
460 unsigned long v;
461
462 switch (cmd) {
463 case HPET_IE_OFF:
464 case HPET_INFO:
465 case HPET_EPI:
466 case HPET_DPI:
467 case HPET_IRQFREQ:
468 timer = devp->hd_timer;
469 hpet = devp->hd_hpet;
470 hpetp = devp->hd_hpets;
471 break;
472 case HPET_IE_ON:
473 return hpet_ioctl_ieon(devp);
474 default:
475 return -EINVAL;
476 }
477
478 err = 0;
479
480 switch (cmd) {
481 case HPET_IE_OFF:
482 if ((devp->hd_flags & HPET_IE) == 0)
483 break;
484 v = readq(&timer->hpet_config);
485 v &= ~Tn_INT_ENB_CNF_MASK;
486 writeq(v, &timer->hpet_config);
487 if (devp->hd_irq) {
488 free_irq(devp->hd_irq, devp);
489 devp->hd_irq = 0;
490 }
491 devp->hd_flags ^= HPET_IE;
492 break;
493 case HPET_INFO:
494 {
495 struct hpet_info info;
496
Clemens Ladischaf95ead2005-10-30 15:03:38 -0800497 if (devp->hd_ireqfreq)
498 info.hi_ireqfreq =
499 hpet_time_div(hpetp, devp->hd_ireqfreq);
500 else
501 info.hi_ireqfreq = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700502 info.hi_flags =
503 readq(&timer->hpet_config) & Tn_PER_INT_CAP_MASK;
Clemens Ladischc860ed92005-10-30 15:03:40 -0800504 info.hi_hpet = hpetp->hp_which;
505 info.hi_timer = devp - hpetp->hp_dev;
Clemens Ladisch8e8505b2005-10-30 15:03:37 -0800506 if (kernel)
507 memcpy((void *)arg, &info, sizeof(info));
508 else
509 if (copy_to_user((void __user *)arg, &info,
510 sizeof(info)))
511 err = -EFAULT;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700512 break;
513 }
514 case HPET_EPI:
515 v = readq(&timer->hpet_config);
516 if ((v & Tn_PER_INT_CAP_MASK) == 0) {
517 err = -ENXIO;
518 break;
519 }
520 devp->hd_flags |= HPET_PERIODIC;
521 break;
522 case HPET_DPI:
523 v = readq(&timer->hpet_config);
524 if ((v & Tn_PER_INT_CAP_MASK) == 0) {
525 err = -ENXIO;
526 break;
527 }
528 if (devp->hd_flags & HPET_PERIODIC &&
529 readq(&timer->hpet_config) & Tn_TYPE_CNF_MASK) {
530 v = readq(&timer->hpet_config);
531 v ^= Tn_TYPE_CNF_MASK;
532 writeq(v, &timer->hpet_config);
533 }
534 devp->hd_flags &= ~HPET_PERIODIC;
535 break;
536 case HPET_IRQFREQ:
537 if (!kernel && (arg > hpet_max_freq) &&
538 !capable(CAP_SYS_RESOURCE)) {
539 err = -EACCES;
540 break;
541 }
542
Clemens Ladisch189e2dd2005-10-30 15:03:33 -0800543 if (!arg) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700544 err = -EINVAL;
545 break;
546 }
547
Clemens Ladischba3f2132005-10-30 15:03:31 -0800548 devp->hd_ireqfreq = hpet_time_div(hpetp, arg);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700549 }
550
551 return err;
552}
553
554static struct file_operations hpet_fops = {
555 .owner = THIS_MODULE,
556 .llseek = no_llseek,
557 .read = hpet_read,
558 .poll = hpet_poll,
559 .ioctl = hpet_ioctl,
560 .open = hpet_open,
561 .release = hpet_release,
562 .fasync = hpet_fasync,
563 .mmap = hpet_mmap,
564};
565
566EXPORT_SYMBOL(hpet_alloc);
567EXPORT_SYMBOL(hpet_register);
568EXPORT_SYMBOL(hpet_unregister);
569EXPORT_SYMBOL(hpet_control);
570
571int hpet_register(struct hpet_task *tp, int periodic)
572{
573 unsigned int i;
574 u64 mask;
575 struct hpet_timer __iomem *timer;
576 struct hpet_dev *devp;
577 struct hpets *hpetp;
578
579 switch (periodic) {
580 case 1:
581 mask = Tn_PER_INT_CAP_MASK;
582 break;
583 case 0:
584 mask = 0;
585 break;
586 default:
587 return -EINVAL;
588 }
589
Clemens Ladisch7522e4e2005-10-30 15:03:39 -0800590 tp->ht_opaque = NULL;
591
Linus Torvalds1da177e2005-04-16 15:20:36 -0700592 spin_lock_irq(&hpet_task_lock);
593 spin_lock(&hpet_lock);
594
595 for (devp = NULL, hpetp = hpets; hpetp && !devp; hpetp = hpetp->hp_next)
596 for (timer = hpetp->hp_hpet->hpet_timers, i = 0;
597 i < hpetp->hp_ntimer; i++, timer++) {
598 if ((readq(&timer->hpet_config) & Tn_PER_INT_CAP_MASK)
599 != mask)
600 continue;
601
602 devp = &hpetp->hp_dev[i];
603
604 if (devp->hd_flags & HPET_OPEN || devp->hd_task) {
605 devp = NULL;
606 continue;
607 }
608
609 tp->ht_opaque = devp;
610 devp->hd_task = tp;
611 break;
612 }
613
614 spin_unlock(&hpet_lock);
615 spin_unlock_irq(&hpet_task_lock);
616
617 if (tp->ht_opaque)
618 return 0;
619 else
620 return -EBUSY;
621}
622
623static inline int hpet_tpcheck(struct hpet_task *tp)
624{
625 struct hpet_dev *devp;
626 struct hpets *hpetp;
627
628 devp = tp->ht_opaque;
629
630 if (!devp)
631 return -ENXIO;
632
633 for (hpetp = hpets; hpetp; hpetp = hpetp->hp_next)
634 if (devp >= hpetp->hp_dev
635 && devp < (hpetp->hp_dev + hpetp->hp_ntimer)
636 && devp->hd_hpet == hpetp->hp_hpet)
637 return 0;
638
639 return -ENXIO;
640}
641
642int hpet_unregister(struct hpet_task *tp)
643{
644 struct hpet_dev *devp;
645 struct hpet_timer __iomem *timer;
646 int err;
647
648 if ((err = hpet_tpcheck(tp)))
649 return err;
650
651 spin_lock_irq(&hpet_task_lock);
652 spin_lock(&hpet_lock);
653
654 devp = tp->ht_opaque;
655 if (devp->hd_task != tp) {
656 spin_unlock(&hpet_lock);
657 spin_unlock_irq(&hpet_task_lock);
658 return -ENXIO;
659 }
660
661 timer = devp->hd_timer;
662 writeq((readq(&timer->hpet_config) & ~Tn_INT_ENB_CNF_MASK),
663 &timer->hpet_config);
664 devp->hd_flags &= ~(HPET_IE | HPET_PERIODIC);
665 devp->hd_task = NULL;
666 spin_unlock(&hpet_lock);
667 spin_unlock_irq(&hpet_task_lock);
668
669 return 0;
670}
671
672int hpet_control(struct hpet_task *tp, unsigned int cmd, unsigned long arg)
673{
674 struct hpet_dev *devp;
675 int err;
676
677 if ((err = hpet_tpcheck(tp)))
678 return err;
679
680 spin_lock_irq(&hpet_lock);
681 devp = tp->ht_opaque;
682 if (devp->hd_task != tp) {
683 spin_unlock_irq(&hpet_lock);
684 return -ENXIO;
685 }
686 spin_unlock_irq(&hpet_lock);
687 return hpet_ioctl_common(devp, cmd, arg, 1);
688}
689
690static ctl_table hpet_table[] = {
691 {
692 .ctl_name = 1,
693 .procname = "max-user-freq",
694 .data = &hpet_max_freq,
695 .maxlen = sizeof(int),
696 .mode = 0644,
697 .proc_handler = &proc_dointvec,
698 },
699 {.ctl_name = 0}
700};
701
702static ctl_table hpet_root[] = {
703 {
704 .ctl_name = 1,
705 .procname = "hpet",
706 .maxlen = 0,
707 .mode = 0555,
708 .child = hpet_table,
709 },
710 {.ctl_name = 0}
711};
712
713static ctl_table dev_root[] = {
714 {
715 .ctl_name = CTL_DEV,
716 .procname = "dev",
717 .maxlen = 0,
718 .mode = 0555,
719 .child = hpet_root,
720 },
721 {.ctl_name = 0}
722};
723
724static struct ctl_table_header *sysctl_header;
725
726static void hpet_register_interpolator(struct hpets *hpetp)
727{
728#ifdef CONFIG_TIME_INTERPOLATION
729 struct time_interpolator *ti;
730
731 ti = kmalloc(sizeof(*ti), GFP_KERNEL);
732 if (!ti)
733 return;
734
735 memset(ti, 0, sizeof(*ti));
736 ti->source = TIME_SOURCE_MMIO64;
737 ti->shift = 10;
738 ti->addr = &hpetp->hp_hpet->hpet_mc;
Clemens Ladischba3f2132005-10-30 15:03:31 -0800739 ti->frequency = hpetp->hp_tick_freq;
Alex Williamson96803822005-09-06 15:17:54 -0700740 ti->drift = HPET_DRIFT;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700741 ti->mask = -1;
742
743 hpetp->hp_interpolator = ti;
744 register_time_interpolator(ti);
745#endif
746}
747
748/*
749 * Adjustment for when arming the timer with
750 * initial conditions. That is, main counter
751 * ticks expired before interrupts are enabled.
752 */
753#define TICK_CALIBRATE (1000UL)
754
755static unsigned long hpet_calibrate(struct hpets *hpetp)
756{
757 struct hpet_timer __iomem *timer = NULL;
758 unsigned long t, m, count, i, flags, start;
759 struct hpet_dev *devp;
760 int j;
761 struct hpet __iomem *hpet;
762
763 for (j = 0, devp = hpetp->hp_dev; j < hpetp->hp_ntimer; j++, devp++)
764 if ((devp->hd_flags & HPET_OPEN) == 0) {
765 timer = devp->hd_timer;
766 break;
767 }
768
769 if (!timer)
770 return 0;
771
Clemens Ladisch3d5640d2005-10-30 15:03:39 -0800772 hpet = hpetp->hp_hpet;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700773 t = read_counter(&timer->hpet_compare);
774
775 i = 0;
Clemens Ladischba3f2132005-10-30 15:03:31 -0800776 count = hpet_time_div(hpetp, TICK_CALIBRATE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700777
778 local_irq_save(flags);
779
780 start = read_counter(&hpet->hpet_mc);
781
782 do {
783 m = read_counter(&hpet->hpet_mc);
784 write_counter(t + m + hpetp->hp_delta, &timer->hpet_compare);
785 } while (i++, (m - start) < count);
786
787 local_irq_restore(flags);
788
789 return (m - start) / i;
790}
791
792int hpet_alloc(struct hpet_data *hdp)
793{
794 u64 cap, mcfg;
795 struct hpet_dev *devp;
796 u32 i, ntimer;
797 struct hpets *hpetp;
798 size_t siz;
799 struct hpet __iomem *hpet;
800 static struct hpets *last = (struct hpets *)0;
Clemens Ladischba3f2132005-10-30 15:03:31 -0800801 unsigned long ns, period;
802 unsigned long long temp;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700803
804 /*
805 * hpet_alloc can be called by platform dependent code.
806 * if platform dependent code has allocated the hpet
807 * ACPI also reports hpet, then we catch it here.
808 */
809 for (hpetp = hpets; hpetp; hpetp = hpetp->hp_next)
810 if (hpetp->hp_hpet == hdp->hd_address)
811 return 0;
812
813 siz = sizeof(struct hpets) + ((hdp->hd_nirqs - 1) *
814 sizeof(struct hpet_dev));
815
816 hpetp = kmalloc(siz, GFP_KERNEL);
817
818 if (!hpetp)
819 return -ENOMEM;
820
821 memset(hpetp, 0, siz);
822
823 hpetp->hp_which = hpet_nhpet++;
824 hpetp->hp_hpet = hdp->hd_address;
825 hpetp->hp_hpet_phys = hdp->hd_phys_address;
826
827 hpetp->hp_ntimer = hdp->hd_nirqs;
828
829 for (i = 0; i < hdp->hd_nirqs; i++)
830 hpetp->hp_dev[i].hd_hdwirq = hdp->hd_irq[i];
831
832 hpet = hpetp->hp_hpet;
833
834 cap = readq(&hpet->hpet_cap);
835
836 ntimer = ((cap & HPET_NUM_TIM_CAP_MASK) >> HPET_NUM_TIM_CAP_SHIFT) + 1;
837
838 if (hpetp->hp_ntimer != ntimer) {
839 printk(KERN_WARNING "hpet: number irqs doesn't agree"
840 " with number of timers\n");
841 kfree(hpetp);
842 return -ENODEV;
843 }
844
845 if (last)
846 last->hp_next = hpetp;
847 else
848 hpets = hpetp;
849
850 last = hpetp;
851
Clemens Ladischba3f2132005-10-30 15:03:31 -0800852 period = (cap & HPET_COUNTER_CLK_PERIOD_MASK) >>
853 HPET_COUNTER_CLK_PERIOD_SHIFT; /* fs, 10^-15 */
854 temp = 1000000000000000uLL; /* 10^15 femtoseconds per second */
855 temp += period >> 1; /* round */
856 do_div(temp, period);
857 hpetp->hp_tick_freq = temp; /* ticks per second */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700858
859 printk(KERN_INFO "hpet%d: at MMIO 0x%lx, IRQ%s",
860 hpetp->hp_which, hdp->hd_phys_address,
861 hpetp->hp_ntimer > 1 ? "s" : "");
862 for (i = 0; i < hpetp->hp_ntimer; i++)
863 printk("%s %d", i > 0 ? "," : "", hdp->hd_irq[i]);
864 printk("\n");
865
Clemens Ladischba3f2132005-10-30 15:03:31 -0800866 ns = period / 1000000; /* convert to nanoseconds, 10^-9 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700867 printk(KERN_INFO "hpet%d: %ldns tick, %d %d-bit timers\n",
868 hpetp->hp_which, ns, hpetp->hp_ntimer,
869 cap & HPET_COUNTER_SIZE_MASK ? 64 : 32);
870
871 mcfg = readq(&hpet->hpet_config);
872 if ((mcfg & HPET_ENABLE_CNF_MASK) == 0) {
873 write_counter(0L, &hpet->hpet_mc);
874 mcfg |= HPET_ENABLE_CNF_MASK;
875 writeq(mcfg, &hpet->hpet_config);
876 }
877
Clemens Ladisch642d30b2005-10-30 15:03:31 -0800878 for (i = 0, devp = hpetp->hp_dev; i < hpetp->hp_ntimer; i++, devp++) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700879 struct hpet_timer __iomem *timer;
880
881 timer = &hpet->hpet_timers[devp - hpetp->hp_dev];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700882
883 devp->hd_hpets = hpetp;
884 devp->hd_hpet = hpet;
885 devp->hd_timer = timer;
886
887 /*
888 * If the timer was reserved by platform code,
889 * then make timer unavailable for opens.
890 */
891 if (hdp->hd_state & (1 << i)) {
892 devp->hd_flags = HPET_OPEN;
893 continue;
894 }
895
896 init_waitqueue_head(&devp->hd_waitqueue);
897 }
898
899 hpetp->hp_delta = hpet_calibrate(hpetp);
900 hpet_register_interpolator(hpetp);
901
902 return 0;
903}
904
905static acpi_status hpet_resources(struct acpi_resource *res, void *data)
906{
907 struct hpet_data *hdp;
908 acpi_status status;
909 struct acpi_resource_address64 addr;
910 struct hpets *hpetp;
911
912 hdp = data;
913
914 status = acpi_resource_to_address64(res, &addr);
915
916 if (ACPI_SUCCESS(status)) {
917 unsigned long size;
918
919 size = addr.max_address_range - addr.min_address_range + 1;
920 hdp->hd_phys_address = addr.min_address_range;
921 hdp->hd_address = ioremap(addr.min_address_range, size);
922
923 for (hpetp = hpets; hpetp; hpetp = hpetp->hp_next)
924 if (hpetp->hp_hpet == hdp->hd_address)
925 return -EBUSY;
926 } else if (res->id == ACPI_RSTYPE_EXT_IRQ) {
927 struct acpi_resource_ext_irq *irqp;
928 int i;
929
930 irqp = &res->data.extended_irq;
931
932 if (irqp->number_of_interrupts > 0) {
933 hdp->hd_nirqs = irqp->number_of_interrupts;
934
Kenji Kaneshigea9bd53b2005-07-28 14:42:00 -0400935 for (i = 0; i < hdp->hd_nirqs; i++) {
936 int rc =
Linus Torvalds1da177e2005-04-16 15:20:36 -0700937 acpi_register_gsi(irqp->interrupts[i],
938 irqp->edge_level,
939 irqp->active_high_low);
Kenji Kaneshigea9bd53b2005-07-28 14:42:00 -0400940 if (rc < 0)
941 return AE_ERROR;
942 hdp->hd_irq[i] = rc;
943 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700944 }
945 }
946
947 return AE_OK;
948}
949
950static int hpet_acpi_add(struct acpi_device *device)
951{
952 acpi_status result;
953 struct hpet_data data;
954
955 memset(&data, 0, sizeof(data));
956
957 result =
958 acpi_walk_resources(device->handle, METHOD_NAME__CRS,
959 hpet_resources, &data);
960
961 if (ACPI_FAILURE(result))
962 return -ENODEV;
963
964 if (!data.hd_address || !data.hd_nirqs) {
965 printk("%s: no address or irqs in _CRS\n", __FUNCTION__);
966 return -ENODEV;
967 }
968
969 return hpet_alloc(&data);
970}
971
972static int hpet_acpi_remove(struct acpi_device *device, int type)
973{
974 /* XXX need to unregister interpolator, dealloc mem, etc */
975 return -EINVAL;
976}
977
978static struct acpi_driver hpet_acpi_driver = {
979 .name = "hpet",
980 .ids = "PNP0103",
981 .ops = {
982 .add = hpet_acpi_add,
983 .remove = hpet_acpi_remove,
984 },
985};
986
987static struct miscdevice hpet_misc = { HPET_MINOR, "hpet", &hpet_fops };
988
989static int __init hpet_init(void)
990{
991 int result;
992
993 result = misc_register(&hpet_misc);
994 if (result < 0)
995 return -ENODEV;
996
997 sysctl_header = register_sysctl_table(dev_root, 0);
998
999 result = acpi_bus_register_driver(&hpet_acpi_driver);
1000 if (result < 0) {
1001 if (sysctl_header)
1002 unregister_sysctl_table(sysctl_header);
1003 misc_deregister(&hpet_misc);
1004 return result;
1005 }
1006
1007 return 0;
1008}
1009
1010static void __exit hpet_exit(void)
1011{
1012 acpi_bus_unregister_driver(&hpet_acpi_driver);
1013
1014 if (sysctl_header)
1015 unregister_sysctl_table(sysctl_header);
1016 misc_deregister(&hpet_misc);
1017
1018 return;
1019}
1020
1021module_init(hpet_init);
1022module_exit(hpet_exit);
1023MODULE_AUTHOR("Bob Picco <Robert.Picco@hp.com>");
1024MODULE_LICENSE("GPL");