Contents of /alx-src/tags/kernel26-2.6.12-alx-r9/drivers/char/hpet.c
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Wed Mar 4 11:03:09 2009 UTC (15 years, 6 months ago) by niro
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Wed Mar 4 11:03:09 2009 UTC (15 years, 6 months ago) by niro
File MIME type: text/plain
File size: 21475 byte(s)
Tag kernel26-2.6.12-alx-r9
1 | /* |
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. |
47 | * http://www.intel.com/labs/platcomp/hpet/hpetspec.htm |
48 | */ |
49 | #define HPET_USER_FREQ (64) |
50 | #define HPET_DRIFT (500) |
51 | |
52 | static u32 hpet_ntimer, hpet_nhpet, hpet_max_freq = HPET_USER_FREQ; |
53 | |
54 | /* A lock for concurrent access by app and isr hpet activity. */ |
55 | static DEFINE_SPINLOCK(hpet_lock); |
56 | /* A lock for concurrent intermodule access to hpet and isr hpet activity. */ |
57 | static DEFINE_SPINLOCK(hpet_task_lock); |
58 | |
59 | #define HPET_DEV_NAME (7) |
60 | |
61 | struct 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 | |
76 | struct hpets { |
77 | struct hpets *hp_next; |
78 | struct hpet __iomem *hp_hpet; |
79 | unsigned long hp_hpet_phys; |
80 | struct time_interpolator *hp_interpolator; |
81 | unsigned long hp_period; |
82 | unsigned long hp_delta; |
83 | unsigned int hp_ntimer; |
84 | unsigned int hp_which; |
85 | struct hpet_dev hp_dev[1]; |
86 | }; |
87 | |
88 | static struct hpets *hpets; |
89 | |
90 | #define HPET_OPEN 0x0001 |
91 | #define HPET_IE 0x0002 /* interrupt enabled */ |
92 | #define HPET_PERIODIC 0x0004 |
93 | |
94 | #if BITS_PER_LONG == 64 |
95 | #define write_counter(V, MC) writeq(V, MC) |
96 | #define read_counter(MC) readq(MC) |
97 | #else |
98 | #define write_counter(V, MC) writel(V, MC) |
99 | #define read_counter(MC) readl(MC) |
100 | #endif |
101 | |
102 | #ifndef readq |
103 | static unsigned long long __inline readq(void __iomem *addr) |
104 | { |
105 | return readl(addr) | (((unsigned long long)readl(addr + 4)) << 32LL); |
106 | } |
107 | #endif |
108 | |
109 | #ifndef writeq |
110 | static void __inline writeq(unsigned long long v, void __iomem *addr) |
111 | { |
112 | writel(v & 0xffffffff, addr); |
113 | writel(v >> 32, addr + 4); |
114 | } |
115 | #endif |
116 | |
117 | static irqreturn_t hpet_interrupt(int irq, void *data, struct pt_regs *regs) |
118 | { |
119 | struct hpet_dev *devp; |
120 | unsigned long isr; |
121 | |
122 | devp = data; |
123 | |
124 | spin_lock(&hpet_lock); |
125 | devp->hd_irqdata++; |
126 | |
127 | /* |
128 | * For non-periodic timers, increment the accumulator. |
129 | * This has the effect of treating non-periodic like periodic. |
130 | */ |
131 | if ((devp->hd_flags & (HPET_IE | HPET_PERIODIC)) == HPET_IE) { |
132 | unsigned long m, t; |
133 | |
134 | t = devp->hd_ireqfreq; |
135 | m = read_counter(&devp->hd_hpet->hpet_mc); |
136 | write_counter(t + m + devp->hd_hpets->hp_delta, |
137 | &devp->hd_timer->hpet_compare); |
138 | } |
139 | |
140 | isr = (1 << (devp - devp->hd_hpets->hp_dev)); |
141 | writeq(isr, &devp->hd_hpet->hpet_isr); |
142 | spin_unlock(&hpet_lock); |
143 | |
144 | spin_lock(&hpet_task_lock); |
145 | if (devp->hd_task) |
146 | devp->hd_task->ht_func(devp->hd_task->ht_data); |
147 | spin_unlock(&hpet_task_lock); |
148 | |
149 | wake_up_interruptible(&devp->hd_waitqueue); |
150 | |
151 | kill_fasync(&devp->hd_async_queue, SIGIO, POLL_IN); |
152 | |
153 | return IRQ_HANDLED; |
154 | } |
155 | |
156 | static int hpet_open(struct inode *inode, struct file *file) |
157 | { |
158 | struct hpet_dev *devp; |
159 | struct hpets *hpetp; |
160 | int i; |
161 | |
162 | if (file->f_mode & FMODE_WRITE) |
163 | return -EINVAL; |
164 | |
165 | spin_lock_irq(&hpet_lock); |
166 | |
167 | for (devp = NULL, hpetp = hpets; hpetp && !devp; hpetp = hpetp->hp_next) |
168 | for (i = 0; i < hpetp->hp_ntimer; i++) |
169 | if (hpetp->hp_dev[i].hd_flags & HPET_OPEN |
170 | || hpetp->hp_dev[i].hd_task) |
171 | continue; |
172 | else { |
173 | devp = &hpetp->hp_dev[i]; |
174 | break; |
175 | } |
176 | |
177 | if (!devp) { |
178 | spin_unlock_irq(&hpet_lock); |
179 | return -EBUSY; |
180 | } |
181 | |
182 | file->private_data = devp; |
183 | devp->hd_irqdata = 0; |
184 | devp->hd_flags |= HPET_OPEN; |
185 | spin_unlock_irq(&hpet_lock); |
186 | |
187 | return 0; |
188 | } |
189 | |
190 | static ssize_t |
191 | hpet_read(struct file *file, char __user *buf, size_t count, loff_t * ppos) |
192 | { |
193 | DECLARE_WAITQUEUE(wait, current); |
194 | unsigned long data; |
195 | ssize_t retval; |
196 | struct hpet_dev *devp; |
197 | |
198 | devp = file->private_data; |
199 | if (!devp->hd_ireqfreq) |
200 | return -EIO; |
201 | |
202 | if (count < sizeof(unsigned long)) |
203 | return -EINVAL; |
204 | |
205 | add_wait_queue(&devp->hd_waitqueue, &wait); |
206 | |
207 | for ( ; ; ) { |
208 | set_current_state(TASK_INTERRUPTIBLE); |
209 | |
210 | spin_lock_irq(&hpet_lock); |
211 | data = devp->hd_irqdata; |
212 | devp->hd_irqdata = 0; |
213 | spin_unlock_irq(&hpet_lock); |
214 | |
215 | if (data) |
216 | break; |
217 | else if (file->f_flags & O_NONBLOCK) { |
218 | retval = -EAGAIN; |
219 | goto out; |
220 | } else if (signal_pending(current)) { |
221 | retval = -ERESTARTSYS; |
222 | goto out; |
223 | } |
224 | schedule(); |
225 | } |
226 | |
227 | retval = put_user(data, (unsigned long __user *)buf); |
228 | if (!retval) |
229 | retval = sizeof(unsigned long); |
230 | out: |
231 | __set_current_state(TASK_RUNNING); |
232 | remove_wait_queue(&devp->hd_waitqueue, &wait); |
233 | |
234 | return retval; |
235 | } |
236 | |
237 | static unsigned int hpet_poll(struct file *file, poll_table * wait) |
238 | { |
239 | unsigned long v; |
240 | struct hpet_dev *devp; |
241 | |
242 | devp = file->private_data; |
243 | |
244 | if (!devp->hd_ireqfreq) |
245 | return 0; |
246 | |
247 | poll_wait(file, &devp->hd_waitqueue, wait); |
248 | |
249 | spin_lock_irq(&hpet_lock); |
250 | v = devp->hd_irqdata; |
251 | spin_unlock_irq(&hpet_lock); |
252 | |
253 | if (v != 0) |
254 | return POLLIN | POLLRDNORM; |
255 | |
256 | return 0; |
257 | } |
258 | |
259 | static int hpet_mmap(struct file *file, struct vm_area_struct *vma) |
260 | { |
261 | #ifdef CONFIG_HPET_MMAP |
262 | struct hpet_dev *devp; |
263 | unsigned long addr; |
264 | |
265 | if (((vma->vm_end - vma->vm_start) != PAGE_SIZE) || vma->vm_pgoff) |
266 | return -EINVAL; |
267 | |
268 | devp = file->private_data; |
269 | addr = devp->hd_hpets->hp_hpet_phys; |
270 | |
271 | if (addr & (PAGE_SIZE - 1)) |
272 | return -ENOSYS; |
273 | |
274 | vma->vm_flags |= VM_IO; |
275 | vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot); |
276 | addr = __pa(addr); |
277 | |
278 | if (io_remap_pfn_range(vma, vma->vm_start, addr >> PAGE_SHIFT, |
279 | PAGE_SIZE, vma->vm_page_prot)) { |
280 | printk(KERN_ERR "remap_pfn_range failed in hpet.c\n"); |
281 | return -EAGAIN; |
282 | } |
283 | |
284 | return 0; |
285 | #else |
286 | return -ENOSYS; |
287 | #endif |
288 | } |
289 | |
290 | static int hpet_fasync(int fd, struct file *file, int on) |
291 | { |
292 | struct hpet_dev *devp; |
293 | |
294 | devp = file->private_data; |
295 | |
296 | if (fasync_helper(fd, file, on, &devp->hd_async_queue) >= 0) |
297 | return 0; |
298 | else |
299 | return -EIO; |
300 | } |
301 | |
302 | static int hpet_release(struct inode *inode, struct file *file) |
303 | { |
304 | struct hpet_dev *devp; |
305 | struct hpet_timer __iomem *timer; |
306 | int irq = 0; |
307 | |
308 | devp = file->private_data; |
309 | timer = devp->hd_timer; |
310 | |
311 | spin_lock_irq(&hpet_lock); |
312 | |
313 | writeq((readq(&timer->hpet_config) & ~Tn_INT_ENB_CNF_MASK), |
314 | &timer->hpet_config); |
315 | |
316 | irq = devp->hd_irq; |
317 | devp->hd_irq = 0; |
318 | |
319 | devp->hd_ireqfreq = 0; |
320 | |
321 | if (devp->hd_flags & HPET_PERIODIC |
322 | && readq(&timer->hpet_config) & Tn_TYPE_CNF_MASK) { |
323 | unsigned long v; |
324 | |
325 | v = readq(&timer->hpet_config); |
326 | v ^= Tn_TYPE_CNF_MASK; |
327 | writeq(v, &timer->hpet_config); |
328 | } |
329 | |
330 | devp->hd_flags &= ~(HPET_OPEN | HPET_IE | HPET_PERIODIC); |
331 | spin_unlock_irq(&hpet_lock); |
332 | |
333 | if (irq) |
334 | free_irq(irq, devp); |
335 | |
336 | if (file->f_flags & FASYNC) |
337 | hpet_fasync(-1, file, 0); |
338 | |
339 | file->private_data = NULL; |
340 | return 0; |
341 | } |
342 | |
343 | static int hpet_ioctl_common(struct hpet_dev *, int, unsigned long, int); |
344 | |
345 | static int |
346 | hpet_ioctl(struct inode *inode, struct file *file, unsigned int cmd, |
347 | unsigned long arg) |
348 | { |
349 | struct hpet_dev *devp; |
350 | |
351 | devp = file->private_data; |
352 | return hpet_ioctl_common(devp, cmd, arg, 0); |
353 | } |
354 | |
355 | static int hpet_ioctl_ieon(struct hpet_dev *devp) |
356 | { |
357 | struct hpet_timer __iomem *timer; |
358 | struct hpet __iomem *hpet; |
359 | struct hpets *hpetp; |
360 | int irq; |
361 | unsigned long g, v, t, m; |
362 | unsigned long flags, isr; |
363 | |
364 | timer = devp->hd_timer; |
365 | hpet = devp->hd_hpet; |
366 | hpetp = devp->hd_hpets; |
367 | |
368 | v = readq(&timer->hpet_config); |
369 | spin_lock_irq(&hpet_lock); |
370 | |
371 | if (devp->hd_flags & HPET_IE) { |
372 | spin_unlock_irq(&hpet_lock); |
373 | return -EBUSY; |
374 | } |
375 | |
376 | devp->hd_flags |= HPET_IE; |
377 | spin_unlock_irq(&hpet_lock); |
378 | |
379 | t = readq(&timer->hpet_config); |
380 | irq = devp->hd_hdwirq; |
381 | |
382 | if (irq) { |
383 | sprintf(devp->hd_name, "hpet%d", (int)(devp - hpetp->hp_dev)); |
384 | |
385 | if (request_irq |
386 | (irq, hpet_interrupt, SA_INTERRUPT, devp->hd_name, (void *)devp)) { |
387 | printk(KERN_ERR "hpet: IRQ %d is not free\n", irq); |
388 | irq = 0; |
389 | } |
390 | } |
391 | |
392 | if (irq == 0) { |
393 | spin_lock_irq(&hpet_lock); |
394 | devp->hd_flags ^= HPET_IE; |
395 | spin_unlock_irq(&hpet_lock); |
396 | return -EIO; |
397 | } |
398 | |
399 | devp->hd_irq = irq; |
400 | t = devp->hd_ireqfreq; |
401 | v = readq(&timer->hpet_config); |
402 | g = v | Tn_INT_ENB_CNF_MASK; |
403 | |
404 | if (devp->hd_flags & HPET_PERIODIC) { |
405 | write_counter(t, &timer->hpet_compare); |
406 | g |= Tn_TYPE_CNF_MASK; |
407 | v |= Tn_TYPE_CNF_MASK; |
408 | writeq(v, &timer->hpet_config); |
409 | v |= Tn_VAL_SET_CNF_MASK; |
410 | writeq(v, &timer->hpet_config); |
411 | local_irq_save(flags); |
412 | m = read_counter(&hpet->hpet_mc); |
413 | write_counter(t + m + hpetp->hp_delta, &timer->hpet_compare); |
414 | } else { |
415 | local_irq_save(flags); |
416 | m = read_counter(&hpet->hpet_mc); |
417 | write_counter(t + m + hpetp->hp_delta, &timer->hpet_compare); |
418 | } |
419 | |
420 | isr = (1 << (devp - hpets->hp_dev)); |
421 | writeq(isr, &hpet->hpet_isr); |
422 | writeq(g, &timer->hpet_config); |
423 | local_irq_restore(flags); |
424 | |
425 | return 0; |
426 | } |
427 | |
428 | static inline unsigned long hpet_time_div(unsigned long dis) |
429 | { |
430 | unsigned long long m = 1000000000000000ULL; |
431 | |
432 | do_div(m, dis); |
433 | |
434 | return (unsigned long)m; |
435 | } |
436 | |
437 | static int |
438 | hpet_ioctl_common(struct hpet_dev *devp, int cmd, unsigned long arg, int kernel) |
439 | { |
440 | struct hpet_timer __iomem *timer; |
441 | struct hpet __iomem *hpet; |
442 | struct hpets *hpetp; |
443 | int err; |
444 | unsigned long v; |
445 | |
446 | switch (cmd) { |
447 | case HPET_IE_OFF: |
448 | case HPET_INFO: |
449 | case HPET_EPI: |
450 | case HPET_DPI: |
451 | case HPET_IRQFREQ: |
452 | timer = devp->hd_timer; |
453 | hpet = devp->hd_hpet; |
454 | hpetp = devp->hd_hpets; |
455 | break; |
456 | case HPET_IE_ON: |
457 | return hpet_ioctl_ieon(devp); |
458 | default: |
459 | return -EINVAL; |
460 | } |
461 | |
462 | err = 0; |
463 | |
464 | switch (cmd) { |
465 | case HPET_IE_OFF: |
466 | if ((devp->hd_flags & HPET_IE) == 0) |
467 | break; |
468 | v = readq(&timer->hpet_config); |
469 | v &= ~Tn_INT_ENB_CNF_MASK; |
470 | writeq(v, &timer->hpet_config); |
471 | if (devp->hd_irq) { |
472 | free_irq(devp->hd_irq, devp); |
473 | devp->hd_irq = 0; |
474 | } |
475 | devp->hd_flags ^= HPET_IE; |
476 | break; |
477 | case HPET_INFO: |
478 | { |
479 | struct hpet_info info; |
480 | |
481 | info.hi_ireqfreq = hpet_time_div(hpetp->hp_period * |
482 | devp->hd_ireqfreq); |
483 | info.hi_flags = |
484 | readq(&timer->hpet_config) & Tn_PER_INT_CAP_MASK; |
485 | info.hi_hpet = devp->hd_hpets->hp_which; |
486 | info.hi_timer = devp - devp->hd_hpets->hp_dev; |
487 | if (copy_to_user((void __user *)arg, &info, sizeof(info))) |
488 | err = -EFAULT; |
489 | break; |
490 | } |
491 | case HPET_EPI: |
492 | v = readq(&timer->hpet_config); |
493 | if ((v & Tn_PER_INT_CAP_MASK) == 0) { |
494 | err = -ENXIO; |
495 | break; |
496 | } |
497 | devp->hd_flags |= HPET_PERIODIC; |
498 | break; |
499 | case HPET_DPI: |
500 | v = readq(&timer->hpet_config); |
501 | if ((v & Tn_PER_INT_CAP_MASK) == 0) { |
502 | err = -ENXIO; |
503 | break; |
504 | } |
505 | if (devp->hd_flags & HPET_PERIODIC && |
506 | readq(&timer->hpet_config) & Tn_TYPE_CNF_MASK) { |
507 | v = readq(&timer->hpet_config); |
508 | v ^= Tn_TYPE_CNF_MASK; |
509 | writeq(v, &timer->hpet_config); |
510 | } |
511 | devp->hd_flags &= ~HPET_PERIODIC; |
512 | break; |
513 | case HPET_IRQFREQ: |
514 | if (!kernel && (arg > hpet_max_freq) && |
515 | !capable(CAP_SYS_RESOURCE)) { |
516 | err = -EACCES; |
517 | break; |
518 | } |
519 | |
520 | if (arg & (arg - 1)) { |
521 | err = -EINVAL; |
522 | break; |
523 | } |
524 | |
525 | devp->hd_ireqfreq = hpet_time_div(hpetp->hp_period * arg); |
526 | } |
527 | |
528 | return err; |
529 | } |
530 | |
531 | static struct file_operations hpet_fops = { |
532 | .owner = THIS_MODULE, |
533 | .llseek = no_llseek, |
534 | .read = hpet_read, |
535 | .poll = hpet_poll, |
536 | .ioctl = hpet_ioctl, |
537 | .open = hpet_open, |
538 | .release = hpet_release, |
539 | .fasync = hpet_fasync, |
540 | .mmap = hpet_mmap, |
541 | }; |
542 | |
543 | EXPORT_SYMBOL(hpet_alloc); |
544 | EXPORT_SYMBOL(hpet_register); |
545 | EXPORT_SYMBOL(hpet_unregister); |
546 | EXPORT_SYMBOL(hpet_control); |
547 | |
548 | int hpet_register(struct hpet_task *tp, int periodic) |
549 | { |
550 | unsigned int i; |
551 | u64 mask; |
552 | struct hpet_timer __iomem *timer; |
553 | struct hpet_dev *devp; |
554 | struct hpets *hpetp; |
555 | |
556 | switch (periodic) { |
557 | case 1: |
558 | mask = Tn_PER_INT_CAP_MASK; |
559 | break; |
560 | case 0: |
561 | mask = 0; |
562 | break; |
563 | default: |
564 | return -EINVAL; |
565 | } |
566 | |
567 | spin_lock_irq(&hpet_task_lock); |
568 | spin_lock(&hpet_lock); |
569 | |
570 | for (devp = NULL, hpetp = hpets; hpetp && !devp; hpetp = hpetp->hp_next) |
571 | for (timer = hpetp->hp_hpet->hpet_timers, i = 0; |
572 | i < hpetp->hp_ntimer; i++, timer++) { |
573 | if ((readq(&timer->hpet_config) & Tn_PER_INT_CAP_MASK) |
574 | != mask) |
575 | continue; |
576 | |
577 | devp = &hpetp->hp_dev[i]; |
578 | |
579 | if (devp->hd_flags & HPET_OPEN || devp->hd_task) { |
580 | devp = NULL; |
581 | continue; |
582 | } |
583 | |
584 | tp->ht_opaque = devp; |
585 | devp->hd_task = tp; |
586 | break; |
587 | } |
588 | |
589 | spin_unlock(&hpet_lock); |
590 | spin_unlock_irq(&hpet_task_lock); |
591 | |
592 | if (tp->ht_opaque) |
593 | return 0; |
594 | else |
595 | return -EBUSY; |
596 | } |
597 | |
598 | static inline int hpet_tpcheck(struct hpet_task *tp) |
599 | { |
600 | struct hpet_dev *devp; |
601 | struct hpets *hpetp; |
602 | |
603 | devp = tp->ht_opaque; |
604 | |
605 | if (!devp) |
606 | return -ENXIO; |
607 | |
608 | for (hpetp = hpets; hpetp; hpetp = hpetp->hp_next) |
609 | if (devp >= hpetp->hp_dev |
610 | && devp < (hpetp->hp_dev + hpetp->hp_ntimer) |
611 | && devp->hd_hpet == hpetp->hp_hpet) |
612 | return 0; |
613 | |
614 | return -ENXIO; |
615 | } |
616 | |
617 | int hpet_unregister(struct hpet_task *tp) |
618 | { |
619 | struct hpet_dev *devp; |
620 | struct hpet_timer __iomem *timer; |
621 | int err; |
622 | |
623 | if ((err = hpet_tpcheck(tp))) |
624 | return err; |
625 | |
626 | spin_lock_irq(&hpet_task_lock); |
627 | spin_lock(&hpet_lock); |
628 | |
629 | devp = tp->ht_opaque; |
630 | if (devp->hd_task != tp) { |
631 | spin_unlock(&hpet_lock); |
632 | spin_unlock_irq(&hpet_task_lock); |
633 | return -ENXIO; |
634 | } |
635 | |
636 | timer = devp->hd_timer; |
637 | writeq((readq(&timer->hpet_config) & ~Tn_INT_ENB_CNF_MASK), |
638 | &timer->hpet_config); |
639 | devp->hd_flags &= ~(HPET_IE | HPET_PERIODIC); |
640 | devp->hd_task = NULL; |
641 | spin_unlock(&hpet_lock); |
642 | spin_unlock_irq(&hpet_task_lock); |
643 | |
644 | return 0; |
645 | } |
646 | |
647 | int hpet_control(struct hpet_task *tp, unsigned int cmd, unsigned long arg) |
648 | { |
649 | struct hpet_dev *devp; |
650 | int err; |
651 | |
652 | if ((err = hpet_tpcheck(tp))) |
653 | return err; |
654 | |
655 | spin_lock_irq(&hpet_lock); |
656 | devp = tp->ht_opaque; |
657 | if (devp->hd_task != tp) { |
658 | spin_unlock_irq(&hpet_lock); |
659 | return -ENXIO; |
660 | } |
661 | spin_unlock_irq(&hpet_lock); |
662 | return hpet_ioctl_common(devp, cmd, arg, 1); |
663 | } |
664 | |
665 | static ctl_table hpet_table[] = { |
666 | { |
667 | .ctl_name = 1, |
668 | .procname = "max-user-freq", |
669 | .data = &hpet_max_freq, |
670 | .maxlen = sizeof(int), |
671 | .mode = 0644, |
672 | .proc_handler = &proc_dointvec, |
673 | }, |
674 | {.ctl_name = 0} |
675 | }; |
676 | |
677 | static ctl_table hpet_root[] = { |
678 | { |
679 | .ctl_name = 1, |
680 | .procname = "hpet", |
681 | .maxlen = 0, |
682 | .mode = 0555, |
683 | .child = hpet_table, |
684 | }, |
685 | {.ctl_name = 0} |
686 | }; |
687 | |
688 | static ctl_table dev_root[] = { |
689 | { |
690 | .ctl_name = CTL_DEV, |
691 | .procname = "dev", |
692 | .maxlen = 0, |
693 | .mode = 0555, |
694 | .child = hpet_root, |
695 | }, |
696 | {.ctl_name = 0} |
697 | }; |
698 | |
699 | static struct ctl_table_header *sysctl_header; |
700 | |
701 | static void hpet_register_interpolator(struct hpets *hpetp) |
702 | { |
703 | #ifdef CONFIG_TIME_INTERPOLATION |
704 | struct time_interpolator *ti; |
705 | |
706 | ti = kmalloc(sizeof(*ti), GFP_KERNEL); |
707 | if (!ti) |
708 | return; |
709 | |
710 | memset(ti, 0, sizeof(*ti)); |
711 | ti->source = TIME_SOURCE_MMIO64; |
712 | ti->shift = 10; |
713 | ti->addr = &hpetp->hp_hpet->hpet_mc; |
714 | ti->frequency = hpet_time_div(hpets->hp_period); |
715 | ti->drift = ti->frequency * HPET_DRIFT / 1000000; |
716 | ti->mask = -1; |
717 | |
718 | hpetp->hp_interpolator = ti; |
719 | register_time_interpolator(ti); |
720 | #endif |
721 | } |
722 | |
723 | /* |
724 | * Adjustment for when arming the timer with |
725 | * initial conditions. That is, main counter |
726 | * ticks expired before interrupts are enabled. |
727 | */ |
728 | #define TICK_CALIBRATE (1000UL) |
729 | |
730 | static unsigned long hpet_calibrate(struct hpets *hpetp) |
731 | { |
732 | struct hpet_timer __iomem *timer = NULL; |
733 | unsigned long t, m, count, i, flags, start; |
734 | struct hpet_dev *devp; |
735 | int j; |
736 | struct hpet __iomem *hpet; |
737 | |
738 | for (j = 0, devp = hpetp->hp_dev; j < hpetp->hp_ntimer; j++, devp++) |
739 | if ((devp->hd_flags & HPET_OPEN) == 0) { |
740 | timer = devp->hd_timer; |
741 | break; |
742 | } |
743 | |
744 | if (!timer) |
745 | return 0; |
746 | |
747 | hpet = hpets->hp_hpet; |
748 | t = read_counter(&timer->hpet_compare); |
749 | |
750 | i = 0; |
751 | count = hpet_time_div(hpetp->hp_period * TICK_CALIBRATE); |
752 | |
753 | local_irq_save(flags); |
754 | |
755 | start = read_counter(&hpet->hpet_mc); |
756 | |
757 | do { |
758 | m = read_counter(&hpet->hpet_mc); |
759 | write_counter(t + m + hpetp->hp_delta, &timer->hpet_compare); |
760 | } while (i++, (m - start) < count); |
761 | |
762 | local_irq_restore(flags); |
763 | |
764 | return (m - start) / i; |
765 | } |
766 | |
767 | int hpet_alloc(struct hpet_data *hdp) |
768 | { |
769 | u64 cap, mcfg; |
770 | struct hpet_dev *devp; |
771 | u32 i, ntimer; |
772 | struct hpets *hpetp; |
773 | size_t siz; |
774 | struct hpet __iomem *hpet; |
775 | static struct hpets *last = (struct hpets *)0; |
776 | unsigned long ns; |
777 | |
778 | /* |
779 | * hpet_alloc can be called by platform dependent code. |
780 | * if platform dependent code has allocated the hpet |
781 | * ACPI also reports hpet, then we catch it here. |
782 | */ |
783 | for (hpetp = hpets; hpetp; hpetp = hpetp->hp_next) |
784 | if (hpetp->hp_hpet == hdp->hd_address) |
785 | return 0; |
786 | |
787 | siz = sizeof(struct hpets) + ((hdp->hd_nirqs - 1) * |
788 | sizeof(struct hpet_dev)); |
789 | |
790 | hpetp = kmalloc(siz, GFP_KERNEL); |
791 | |
792 | if (!hpetp) |
793 | return -ENOMEM; |
794 | |
795 | memset(hpetp, 0, siz); |
796 | |
797 | hpetp->hp_which = hpet_nhpet++; |
798 | hpetp->hp_hpet = hdp->hd_address; |
799 | hpetp->hp_hpet_phys = hdp->hd_phys_address; |
800 | |
801 | hpetp->hp_ntimer = hdp->hd_nirqs; |
802 | |
803 | for (i = 0; i < hdp->hd_nirqs; i++) |
804 | hpetp->hp_dev[i].hd_hdwirq = hdp->hd_irq[i]; |
805 | |
806 | hpet = hpetp->hp_hpet; |
807 | |
808 | cap = readq(&hpet->hpet_cap); |
809 | |
810 | ntimer = ((cap & HPET_NUM_TIM_CAP_MASK) >> HPET_NUM_TIM_CAP_SHIFT) + 1; |
811 | |
812 | if (hpetp->hp_ntimer != ntimer) { |
813 | printk(KERN_WARNING "hpet: number irqs doesn't agree" |
814 | " with number of timers\n"); |
815 | kfree(hpetp); |
816 | return -ENODEV; |
817 | } |
818 | |
819 | if (last) |
820 | last->hp_next = hpetp; |
821 | else |
822 | hpets = hpetp; |
823 | |
824 | last = hpetp; |
825 | |
826 | hpetp->hp_period = (cap & HPET_COUNTER_CLK_PERIOD_MASK) >> |
827 | HPET_COUNTER_CLK_PERIOD_SHIFT; |
828 | |
829 | printk(KERN_INFO "hpet%d: at MMIO 0x%lx, IRQ%s", |
830 | hpetp->hp_which, hdp->hd_phys_address, |
831 | hpetp->hp_ntimer > 1 ? "s" : ""); |
832 | for (i = 0; i < hpetp->hp_ntimer; i++) |
833 | printk("%s %d", i > 0 ? "," : "", hdp->hd_irq[i]); |
834 | printk("\n"); |
835 | |
836 | ns = hpetp->hp_period; /* femptoseconds, 10^-15 */ |
837 | do_div(ns, 1000000); /* convert to nanoseconds, 10^-9 */ |
838 | printk(KERN_INFO "hpet%d: %ldns tick, %d %d-bit timers\n", |
839 | hpetp->hp_which, ns, hpetp->hp_ntimer, |
840 | cap & HPET_COUNTER_SIZE_MASK ? 64 : 32); |
841 | |
842 | mcfg = readq(&hpet->hpet_config); |
843 | if ((mcfg & HPET_ENABLE_CNF_MASK) == 0) { |
844 | write_counter(0L, &hpet->hpet_mc); |
845 | mcfg |= HPET_ENABLE_CNF_MASK; |
846 | writeq(mcfg, &hpet->hpet_config); |
847 | } |
848 | |
849 | for (i = 0, devp = hpetp->hp_dev; i < hpetp->hp_ntimer; |
850 | i++, hpet_ntimer++, devp++) { |
851 | unsigned long v; |
852 | struct hpet_timer __iomem *timer; |
853 | |
854 | timer = &hpet->hpet_timers[devp - hpetp->hp_dev]; |
855 | v = readq(&timer->hpet_config); |
856 | |
857 | devp->hd_hpets = hpetp; |
858 | devp->hd_hpet = hpet; |
859 | devp->hd_timer = timer; |
860 | |
861 | /* |
862 | * If the timer was reserved by platform code, |
863 | * then make timer unavailable for opens. |
864 | */ |
865 | if (hdp->hd_state & (1 << i)) { |
866 | devp->hd_flags = HPET_OPEN; |
867 | continue; |
868 | } |
869 | |
870 | init_waitqueue_head(&devp->hd_waitqueue); |
871 | } |
872 | |
873 | hpetp->hp_delta = hpet_calibrate(hpetp); |
874 | hpet_register_interpolator(hpetp); |
875 | |
876 | return 0; |
877 | } |
878 | |
879 | static acpi_status hpet_resources(struct acpi_resource *res, void *data) |
880 | { |
881 | struct hpet_data *hdp; |
882 | acpi_status status; |
883 | struct acpi_resource_address64 addr; |
884 | struct hpets *hpetp; |
885 | |
886 | hdp = data; |
887 | |
888 | status = acpi_resource_to_address64(res, &addr); |
889 | |
890 | if (ACPI_SUCCESS(status)) { |
891 | unsigned long size; |
892 | |
893 | size = addr.max_address_range - addr.min_address_range + 1; |
894 | hdp->hd_phys_address = addr.min_address_range; |
895 | hdp->hd_address = ioremap(addr.min_address_range, size); |
896 | |
897 | for (hpetp = hpets; hpetp; hpetp = hpetp->hp_next) |
898 | if (hpetp->hp_hpet == hdp->hd_address) |
899 | return -EBUSY; |
900 | } else if (res->id == ACPI_RSTYPE_EXT_IRQ) { |
901 | struct acpi_resource_ext_irq *irqp; |
902 | int i; |
903 | |
904 | irqp = &res->data.extended_irq; |
905 | |
906 | if (irqp->number_of_interrupts > 0) { |
907 | hdp->hd_nirqs = irqp->number_of_interrupts; |
908 | |
909 | for (i = 0; i < hdp->hd_nirqs; i++) |
910 | hdp->hd_irq[i] = |
911 | acpi_register_gsi(irqp->interrupts[i], |
912 | irqp->edge_level, |
913 | irqp->active_high_low); |
914 | } |
915 | } |
916 | |
917 | return AE_OK; |
918 | } |
919 | |
920 | static int hpet_acpi_add(struct acpi_device *device) |
921 | { |
922 | acpi_status result; |
923 | struct hpet_data data; |
924 | |
925 | memset(&data, 0, sizeof(data)); |
926 | |
927 | result = |
928 | acpi_walk_resources(device->handle, METHOD_NAME__CRS, |
929 | hpet_resources, &data); |
930 | |
931 | if (ACPI_FAILURE(result)) |
932 | return -ENODEV; |
933 | |
934 | if (!data.hd_address || !data.hd_nirqs) { |
935 | printk("%s: no address or irqs in _CRS\n", __FUNCTION__); |
936 | return -ENODEV; |
937 | } |
938 | |
939 | return hpet_alloc(&data); |
940 | } |
941 | |
942 | static int hpet_acpi_remove(struct acpi_device *device, int type) |
943 | { |
944 | /* XXX need to unregister interpolator, dealloc mem, etc */ |
945 | return -EINVAL; |
946 | } |
947 | |
948 | static struct acpi_driver hpet_acpi_driver = { |
949 | .name = "hpet", |
950 | .ids = "PNP0103", |
951 | .ops = { |
952 | .add = hpet_acpi_add, |
953 | .remove = hpet_acpi_remove, |
954 | }, |
955 | }; |
956 | |
957 | static struct miscdevice hpet_misc = { HPET_MINOR, "hpet", &hpet_fops }; |
958 | |
959 | static int __init hpet_init(void) |
960 | { |
961 | int result; |
962 | |
963 | result = misc_register(&hpet_misc); |
964 | if (result < 0) |
965 | return -ENODEV; |
966 | |
967 | sysctl_header = register_sysctl_table(dev_root, 0); |
968 | |
969 | result = acpi_bus_register_driver(&hpet_acpi_driver); |
970 | if (result < 0) { |
971 | if (sysctl_header) |
972 | unregister_sysctl_table(sysctl_header); |
973 | misc_deregister(&hpet_misc); |
974 | return result; |
975 | } |
976 | |
977 | return 0; |
978 | } |
979 | |
980 | static void __exit hpet_exit(void) |
981 | { |
982 | acpi_bus_unregister_driver(&hpet_acpi_driver); |
983 | |
984 | if (sysctl_header) |
985 | unregister_sysctl_table(sysctl_header); |
986 | misc_deregister(&hpet_misc); |
987 | |
988 | return; |
989 | } |
990 | |
991 | module_init(hpet_init); |
992 | module_exit(hpet_exit); |
993 | MODULE_AUTHOR("Bob Picco <Robert.Picco@hp.com>"); |
994 | MODULE_LICENSE("GPL"); |