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/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> 25 #include <linux/mm.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> 34 35 #include <asm/current.h> 36 #include <asm/uaccess.h> 37 #include <asm/system.h> 38 #include <asm/io.h> 39 #include <asm/irq.h> 40 #include <asm/div64.h> 41 42 #include <linux/acpi.h> 43 #include <acpi/acpi_bus.h> 44 #include <linux/hpet.h> 45 46 /* 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 50 */ 51 #define HPET_USER_FREQ (64) 52 #define HPET_DRIFT (500) 53 54 #define HPET_RANGE_SIZE 1024 /* from HPET spec */ 55 56 #if BITS_PER_LONG == 64 57 #define write_counter(V, MC) writeq(V, MC) 58 #define read_counter(MC) readq(MC) 59 #else 60 #define write_counter(V, MC) writel(V, MC) 61 #define read_counter(MC) readl(MC) 62 #endif 63 64 static u32 hpet_nhpet, hpet_max_freq = HPET_USER_FREQ; 65 66 /* This clocksource driver currently only works on ia64 */ 67 #ifdef CONFIG_IA64 68 static void __iomem *hpet_mctr; 69 70 static cycle_t read_hpet(void) 71 { 72 return (cycle_t)read_counter((void __iomem *)hpet_mctr); 73 } 74 75 static struct clocksource clocksource_hpet = { 76 .name = "hpet", 77 .rating = 250, 78 .read = read_hpet, 79 .mask = CLOCKSOURCE_MASK(64), 80 .mult = 0, /*to be caluclated*/ 81 .shift = 10, 82 .flags = CLOCK_SOURCE_IS_CONTINUOUS, 83 }; 84 static struct clocksource *hpet_clocksource; 85 #endif 86 87 /* A lock for concurrent access by app and isr hpet activity. */ 88 static DEFINE_SPINLOCK(hpet_lock); 89 /* A lock for concurrent intermodule access to hpet and isr hpet activity. */ 90 static DEFINE_SPINLOCK(hpet_task_lock); 91 92 #define HPET_DEV_NAME (7) 93 94 struct hpet_dev { 95 struct hpets *hd_hpets; 96 struct hpet __iomem *hd_hpet; 97 struct hpet_timer __iomem *hd_timer; 98 unsigned long hd_ireqfreq; 99 unsigned long hd_irqdata; 100 wait_queue_head_t hd_waitqueue; 101 struct fasync_struct *hd_async_queue; 102 struct hpet_task *hd_task; 103 unsigned int hd_flags; 104 unsigned int hd_irq; 105 unsigned int hd_hdwirq; 106 char hd_name[HPET_DEV_NAME]; 107 }; 108 109 struct hpets { 110 struct hpets *hp_next; 111 struct hpet __iomem *hp_hpet; 112 unsigned long hp_hpet_phys; 113 struct clocksource *hp_clocksource; 114 unsigned long long hp_tick_freq; 115 unsigned long hp_delta; 116 unsigned int hp_ntimer; 117 unsigned int hp_which; 118 struct hpet_dev hp_dev[1]; 119 }; 120 121 static struct hpets *hpets; 122 123 #define HPET_OPEN 0x0001 124 #define HPET_IE 0x0002 /* interrupt enabled */ 125 #define HPET_PERIODIC 0x0004 126 #define HPET_SHARED_IRQ 0x0008 127 128 129 #ifndef readq 130 static inline unsigned long long readq(void __iomem *addr) 131 { 132 return readl(addr) | (((unsigned long long)readl(addr + 4)) << 32LL); 133 } 134 #endif 135 136 #ifndef writeq 137 static inline void writeq(unsigned long long v, void __iomem *addr) 138 { 139 writel(v & 0xffffffff, addr); 140 writel(v >> 32, addr + 4); 141 } 142 #endif 143 144 static irqreturn_t hpet_interrupt(int irq, void *data) 145 { 146 struct hpet_dev *devp; 147 unsigned long isr; 148 149 devp = data; 150 isr = 1 << (devp - devp->hd_hpets->hp_dev); 151 152 if ((devp->hd_flags & HPET_SHARED_IRQ) && 153 !(isr & readl(&devp->hd_hpet->hpet_isr))) 154 return IRQ_NONE; 155 156 spin_lock(&hpet_lock); 157 devp->hd_irqdata++; 158 159 /* 160 * For non-periodic timers, increment the accumulator. 161 * This has the effect of treating non-periodic like periodic. 162 */ 163 if ((devp->hd_flags & (HPET_IE | HPET_PERIODIC)) == HPET_IE) { 164 unsigned long m, t; 165 166 t = devp->hd_ireqfreq; 167 m = read_counter(&devp->hd_hpet->hpet_mc); 168 write_counter(t + m + devp->hd_hpets->hp_delta, 169 &devp->hd_timer->hpet_compare); 170 } 171 172 if (devp->hd_flags & HPET_SHARED_IRQ) 173 writel(isr, &devp->hd_hpet->hpet_isr); 174 spin_unlock(&hpet_lock); 175 176 spin_lock(&hpet_task_lock); 177 if (devp->hd_task) 178 devp->hd_task->ht_func(devp->hd_task->ht_data); 179 spin_unlock(&hpet_task_lock); 180 181 wake_up_interruptible(&devp->hd_waitqueue); 182 183 kill_fasync(&devp->hd_async_queue, SIGIO, POLL_IN); 184 185 return IRQ_HANDLED; 186 } 187 188 static int hpet_open(struct inode *inode, struct file *file) 189 { 190 struct hpet_dev *devp; 191 struct hpets *hpetp; 192 int i; 193 194 if (file->f_mode & FMODE_WRITE) 195 return -EINVAL; 196 197 lock_kernel(); 198 spin_lock_irq(&hpet_lock); 199 200 for (devp = NULL, hpetp = hpets; hpetp && !devp; hpetp = hpetp->hp_next) 201 for (i = 0; i < hpetp->hp_ntimer; i++) 202 if (hpetp->hp_dev[i].hd_flags & HPET_OPEN 203 || hpetp->hp_dev[i].hd_task) 204 continue; 205 else { 206 devp = &hpetp->hp_dev[i]; 207 break; 208 } 209 210 if (!devp) { 211 spin_unlock_irq(&hpet_lock); 212 unlock_kernel(); 213 return -EBUSY; 214 } 215 216 file->private_data = devp; 217 devp->hd_irqdata = 0; 218 devp->hd_flags |= HPET_OPEN; 219 spin_unlock_irq(&hpet_lock); 220 unlock_kernel(); 221 222 return 0; 223 } 224 225 static ssize_t 226 hpet_read(struct file *file, char __user *buf, size_t count, loff_t * ppos) 227 { 228 DECLARE_WAITQUEUE(wait, current); 229 unsigned long data; 230 ssize_t retval; 231 struct hpet_dev *devp; 232 233 devp = file->private_data; 234 if (!devp->hd_ireqfreq) 235 return -EIO; 236 237 if (count < sizeof(unsigned long)) 238 return -EINVAL; 239 240 add_wait_queue(&devp->hd_waitqueue, &wait); 241 242 for ( ; ; ) { 243 set_current_state(TASK_INTERRUPTIBLE); 244 245 spin_lock_irq(&hpet_lock); 246 data = devp->hd_irqdata; 247 devp->hd_irqdata = 0; 248 spin_unlock_irq(&hpet_lock); 249 250 if (data) 251 break; 252 else if (file->f_flags & O_NONBLOCK) { 253 retval = -EAGAIN; 254 goto out; 255 } else if (signal_pending(current)) { 256 retval = -ERESTARTSYS; 257 goto out; 258 } 259 schedule(); 260 } 261 262 retval = put_user(data, (unsigned long __user *)buf); 263 if (!retval) 264 retval = sizeof(unsigned long); 265 out: 266 __set_current_state(TASK_RUNNING); 267 remove_wait_queue(&devp->hd_waitqueue, &wait); 268 269 return retval; 270 } 271 272 static unsigned int hpet_poll(struct file *file, poll_table * wait) 273 { 274 unsigned long v; 275 struct hpet_dev *devp; 276 277 devp = file->private_data; 278 279 if (!devp->hd_ireqfreq) 280 return 0; 281 282 poll_wait(file, &devp->hd_waitqueue, wait); 283 284 spin_lock_irq(&hpet_lock); 285 v = devp->hd_irqdata; 286 spin_unlock_irq(&hpet_lock); 287 288 if (v != 0) 289 return POLLIN | POLLRDNORM; 290 291 return 0; 292 } 293 294 static int hpet_mmap(struct file *file, struct vm_area_struct *vma) 295 { 296 #ifdef CONFIG_HPET_MMAP 297 struct hpet_dev *devp; 298 unsigned long addr; 299 300 if (((vma->vm_end - vma->vm_start) != PAGE_SIZE) || vma->vm_pgoff) 301 return -EINVAL; 302 303 devp = file->private_data; 304 addr = devp->hd_hpets->hp_hpet_phys; 305 306 if (addr & (PAGE_SIZE - 1)) 307 return -ENOSYS; 308 309 vma->vm_flags |= VM_IO; 310 vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot); 311 312 if (io_remap_pfn_range(vma, vma->vm_start, addr >> PAGE_SHIFT, 313 PAGE_SIZE, vma->vm_page_prot)) { 314 printk(KERN_ERR "%s: io_remap_pfn_range failed\n", 315 __func__); 316 return -EAGAIN; 317 } 318 319 return 0; 320 #else 321 return -ENOSYS; 322 #endif 323 } 324 325 static int hpet_fasync(int fd, struct file *file, int on) 326 { 327 struct hpet_dev *devp; 328 329 devp = file->private_data; 330 331 if (fasync_helper(fd, file, on, &devp->hd_async_queue) >= 0) 332 return 0; 333 else 334 return -EIO; 335 } 336 337 static int hpet_release(struct inode *inode, struct file *file) 338 { 339 struct hpet_dev *devp; 340 struct hpet_timer __iomem *timer; 341 int irq = 0; 342 343 devp = file->private_data; 344 timer = devp->hd_timer; 345 346 spin_lock_irq(&hpet_lock); 347 348 writeq((readq(&timer->hpet_config) & ~Tn_INT_ENB_CNF_MASK), 349 &timer->hpet_config); 350 351 irq = devp->hd_irq; 352 devp->hd_irq = 0; 353 354 devp->hd_ireqfreq = 0; 355 356 if (devp->hd_flags & HPET_PERIODIC 357 && readq(&timer->hpet_config) & Tn_TYPE_CNF_MASK) { 358 unsigned long v; 359 360 v = readq(&timer->hpet_config); 361 v ^= Tn_TYPE_CNF_MASK; 362 writeq(v, &timer->hpet_config); 363 } 364 365 devp->hd_flags &= ~(HPET_OPEN | HPET_IE | HPET_PERIODIC); 366 spin_unlock_irq(&hpet_lock); 367 368 if (irq) 369 free_irq(irq, devp); 370 371 if (file->f_flags & FASYNC) 372 hpet_fasync(-1, file, 0); 373 374 file->private_data = NULL; 375 return 0; 376 } 377 378 static int hpet_ioctl_common(struct hpet_dev *, int, unsigned long, int); 379 380 static int 381 hpet_ioctl(struct inode *inode, struct file *file, unsigned int cmd, 382 unsigned long arg) 383 { 384 struct hpet_dev *devp; 385 386 devp = file->private_data; 387 return hpet_ioctl_common(devp, cmd, arg, 0); 388 } 389 390 static int hpet_ioctl_ieon(struct hpet_dev *devp) 391 { 392 struct hpet_timer __iomem *timer; 393 struct hpet __iomem *hpet; 394 struct hpets *hpetp; 395 int irq; 396 unsigned long g, v, t, m; 397 unsigned long flags, isr; 398 399 timer = devp->hd_timer; 400 hpet = devp->hd_hpet; 401 hpetp = devp->hd_hpets; 402 403 if (!devp->hd_ireqfreq) 404 return -EIO; 405 406 spin_lock_irq(&hpet_lock); 407 408 if (devp->hd_flags & HPET_IE) { 409 spin_unlock_irq(&hpet_lock); 410 return -EBUSY; 411 } 412 413 devp->hd_flags |= HPET_IE; 414 415 if (readl(&timer->hpet_config) & Tn_INT_TYPE_CNF_MASK) 416 devp->hd_flags |= HPET_SHARED_IRQ; 417 spin_unlock_irq(&hpet_lock); 418 419 irq = devp->hd_hdwirq; 420 421 if (irq) { 422 unsigned long irq_flags; 423 424 sprintf(devp->hd_name, "hpet%d", (int)(devp - hpetp->hp_dev)); 425 irq_flags = devp->hd_flags & HPET_SHARED_IRQ 426 ? IRQF_SHARED : IRQF_DISABLED; 427 if (request_irq(irq, hpet_interrupt, irq_flags, 428 devp->hd_name, (void *)devp)) { 429 printk(KERN_ERR "hpet: IRQ %d is not free\n", irq); 430 irq = 0; 431 } 432 } 433 434 if (irq == 0) { 435 spin_lock_irq(&hpet_lock); 436 devp->hd_flags ^= HPET_IE; 437 spin_unlock_irq(&hpet_lock); 438 return -EIO; 439 } 440 441 devp->hd_irq = irq; 442 t = devp->hd_ireqfreq; 443 v = readq(&timer->hpet_config); 444 g = v | Tn_INT_ENB_CNF_MASK; 445 446 if (devp->hd_flags & HPET_PERIODIC) { 447 write_counter(t, &timer->hpet_compare); 448 g |= Tn_TYPE_CNF_MASK; 449 v |= Tn_TYPE_CNF_MASK; 450 writeq(v, &timer->hpet_config); 451 v |= Tn_VAL_SET_CNF_MASK; 452 writeq(v, &timer->hpet_config); 453 local_irq_save(flags); 454 m = read_counter(&hpet->hpet_mc); 455 write_counter(t + m + hpetp->hp_delta, &timer->hpet_compare); 456 } else { 457 local_irq_save(flags); 458 m = read_counter(&hpet->hpet_mc); 459 write_counter(t + m + hpetp->hp_delta, &timer->hpet_compare); 460 } 461 462 if (devp->hd_flags & HPET_SHARED_IRQ) { 463 isr = 1 << (devp - devp->hd_hpets->hp_dev); 464 writel(isr, &hpet->hpet_isr); 465 } 466 writeq(g, &timer->hpet_config); 467 local_irq_restore(flags); 468 469 return 0; 470 } 471 472 /* converts Hz to number of timer ticks */ 473 static inline unsigned long hpet_time_div(struct hpets *hpets, 474 unsigned long dis) 475 { 476 unsigned long long m; 477 478 m = hpets->hp_tick_freq + (dis >> 1); 479 do_div(m, dis); 480 return (unsigned long)m; 481 } 482 483 static int 484 hpet_ioctl_common(struct hpet_dev *devp, int cmd, unsigned long arg, int kernel) 485 { 486 struct hpet_timer __iomem *timer; 487 struct hpet __iomem *hpet; 488 struct hpets *hpetp; 489 int err; 490 unsigned long v; 491 492 switch (cmd) { 493 case HPET_IE_OFF: 494 case HPET_INFO: 495 case HPET_EPI: 496 case HPET_DPI: 497 case HPET_IRQFREQ: 498 timer = devp->hd_timer; 499 hpet = devp->hd_hpet; 500 hpetp = devp->hd_hpets; 501 break; 502 case HPET_IE_ON: 503 return hpet_ioctl_ieon(devp); 504 default: 505 return -EINVAL; 506 } 507 508 err = 0; 509 510 switch (cmd) { 511 case HPET_IE_OFF: 512 if ((devp->hd_flags & HPET_IE) == 0) 513 break; 514 v = readq(&timer->hpet_config); 515 v &= ~Tn_INT_ENB_CNF_MASK; 516 writeq(v, &timer->hpet_config); 517 if (devp->hd_irq) { 518 free_irq(devp->hd_irq, devp); 519 devp->hd_irq = 0; 520 } 521 devp->hd_flags ^= HPET_IE; 522 break; 523 case HPET_INFO: 524 { 525 struct hpet_info info; 526 527 if (devp->hd_ireqfreq) 528 info.hi_ireqfreq = 529 hpet_time_div(hpetp, devp->hd_ireqfreq); 530 else 531 info.hi_ireqfreq = 0; 532 info.hi_flags = 533 readq(&timer->hpet_config) & Tn_PER_INT_CAP_MASK; 534 info.hi_hpet = hpetp->hp_which; 535 info.hi_timer = devp - hpetp->hp_dev; 536 if (kernel) 537 memcpy((void *)arg, &info, sizeof(info)); 538 else 539 if (copy_to_user((void __user *)arg, &info, 540 sizeof(info))) 541 err = -EFAULT; 542 break; 543 } 544 case HPET_EPI: 545 v = readq(&timer->hpet_config); 546 if ((v & Tn_PER_INT_CAP_MASK) == 0) { 547 err = -ENXIO; 548 break; 549 } 550 devp->hd_flags |= HPET_PERIODIC; 551 break; 552 case HPET_DPI: 553 v = readq(&timer->hpet_config); 554 if ((v & Tn_PER_INT_CAP_MASK) == 0) { 555 err = -ENXIO; 556 break; 557 } 558 if (devp->hd_flags & HPET_PERIODIC && 559 readq(&timer->hpet_config) & Tn_TYPE_CNF_MASK) { 560 v = readq(&timer->hpet_config); 561 v ^= Tn_TYPE_CNF_MASK; 562 writeq(v, &timer->hpet_config); 563 } 564 devp->hd_flags &= ~HPET_PERIODIC; 565 break; 566 case HPET_IRQFREQ: 567 if (!kernel && (arg > hpet_max_freq) && 568 !capable(CAP_SYS_RESOURCE)) { 569 err = -EACCES; 570 break; 571 } 572 573 if (!arg) { 574 err = -EINVAL; 575 break; 576 } 577 578 devp->hd_ireqfreq = hpet_time_div(hpetp, arg); 579 } 580 581 return err; 582 } 583 584 static const struct file_operations hpet_fops = { 585 .owner = THIS_MODULE, 586 .llseek = no_llseek, 587 .read = hpet_read, 588 .poll = hpet_poll, 589 .ioctl = hpet_ioctl, 590 .open = hpet_open, 591 .release = hpet_release, 592 .fasync = hpet_fasync, 593 .mmap = hpet_mmap, 594 }; 595 596 static int hpet_is_known(struct hpet_data *hdp) 597 { 598 struct hpets *hpetp; 599 600 for (hpetp = hpets; hpetp; hpetp = hpetp->hp_next) 601 if (hpetp->hp_hpet_phys == hdp->hd_phys_address) 602 return 1; 603 604 return 0; 605 } 606 607 static inline int hpet_tpcheck(struct hpet_task *tp) 608 { 609 struct hpet_dev *devp; 610 struct hpets *hpetp; 611 612 devp = tp->ht_opaque; 613 614 if (!devp) 615 return -ENXIO; 616 617 for (hpetp = hpets; hpetp; hpetp = hpetp->hp_next) 618 if (devp >= hpetp->hp_dev 619 && devp < (hpetp->hp_dev + hpetp->hp_ntimer) 620 && devp->hd_hpet == hpetp->hp_hpet) 621 return 0; 622 623 return -ENXIO; 624 } 625 626 #if 0 627 int hpet_unregister(struct hpet_task *tp) 628 { 629 struct hpet_dev *devp; 630 struct hpet_timer __iomem *timer; 631 int err; 632 633 if ((err = hpet_tpcheck(tp))) 634 return err; 635 636 spin_lock_irq(&hpet_task_lock); 637 spin_lock(&hpet_lock); 638 639 devp = tp->ht_opaque; 640 if (devp->hd_task != tp) { 641 spin_unlock(&hpet_lock); 642 spin_unlock_irq(&hpet_task_lock); 643 return -ENXIO; 644 } 645 646 timer = devp->hd_timer; 647 writeq((readq(&timer->hpet_config) & ~Tn_INT_ENB_CNF_MASK), 648 &timer->hpet_config); 649 devp->hd_flags &= ~(HPET_IE | HPET_PERIODIC); 650 devp->hd_task = NULL; 651 spin_unlock(&hpet_lock); 652 spin_unlock_irq(&hpet_task_lock); 653 654 return 0; 655 } 656 #endif /* 0 */ 657 658 static ctl_table hpet_table[] = { 659 { 660 .ctl_name = CTL_UNNUMBERED, 661 .procname = "max-user-freq", 662 .data = &hpet_max_freq, 663 .maxlen = sizeof(int), 664 .mode = 0644, 665 .proc_handler = &proc_dointvec, 666 }, 667 {.ctl_name = 0} 668 }; 669 670 static ctl_table hpet_root[] = { 671 { 672 .ctl_name = CTL_UNNUMBERED, 673 .procname = "hpet", 674 .maxlen = 0, 675 .mode = 0555, 676 .child = hpet_table, 677 }, 678 {.ctl_name = 0} 679 }; 680 681 static ctl_table dev_root[] = { 682 { 683 .ctl_name = CTL_DEV, 684 .procname = "dev", 685 .maxlen = 0, 686 .mode = 0555, 687 .child = hpet_root, 688 }, 689 {.ctl_name = 0} 690 }; 691 692 static struct ctl_table_header *sysctl_header; 693 694 /* 695 * Adjustment for when arming the timer with 696 * initial conditions. That is, main counter 697 * ticks expired before interrupts are enabled. 698 */ 699 #define TICK_CALIBRATE (1000UL) 700 701 static unsigned long hpet_calibrate(struct hpets *hpetp) 702 { 703 struct hpet_timer __iomem *timer = NULL; 704 unsigned long t, m, count, i, flags, start; 705 struct hpet_dev *devp; 706 int j; 707 struct hpet __iomem *hpet; 708 709 for (j = 0, devp = hpetp->hp_dev; j < hpetp->hp_ntimer; j++, devp++) 710 if ((devp->hd_flags & HPET_OPEN) == 0) { 711 timer = devp->hd_timer; 712 break; 713 } 714 715 if (!timer) 716 return 0; 717 718 hpet = hpetp->hp_hpet; 719 t = read_counter(&timer->hpet_compare); 720 721 i = 0; 722 count = hpet_time_div(hpetp, TICK_CALIBRATE); 723 724 local_irq_save(flags); 725 726 start = read_counter(&hpet->hpet_mc); 727 728 do { 729 m = read_counter(&hpet->hpet_mc); 730 write_counter(t + m + hpetp->hp_delta, &timer->hpet_compare); 731 } while (i++, (m - start) < count); 732 733 local_irq_restore(flags); 734 735 return (m - start) / i; 736 } 737 738 int hpet_alloc(struct hpet_data *hdp) 739 { 740 u64 cap, mcfg; 741 struct hpet_dev *devp; 742 u32 i, ntimer; 743 struct hpets *hpetp; 744 size_t siz; 745 struct hpet __iomem *hpet; 746 static struct hpets *last = NULL; 747 unsigned long period; 748 unsigned long long temp; 749 750 /* 751 * hpet_alloc can be called by platform dependent code. 752 * If platform dependent code has allocated the hpet that 753 * ACPI has also reported, then we catch it here. 754 */ 755 if (hpet_is_known(hdp)) { 756 printk(KERN_DEBUG "%s: duplicate HPET ignored\n", 757 __func__); 758 return 0; 759 } 760 761 siz = sizeof(struct hpets) + ((hdp->hd_nirqs - 1) * 762 sizeof(struct hpet_dev)); 763 764 hpetp = kzalloc(siz, GFP_KERNEL); 765 766 if (!hpetp) 767 return -ENOMEM; 768 769 hpetp->hp_which = hpet_nhpet++; 770 hpetp->hp_hpet = hdp->hd_address; 771 hpetp->hp_hpet_phys = hdp->hd_phys_address; 772 773 hpetp->hp_ntimer = hdp->hd_nirqs; 774 775 for (i = 0; i < hdp->hd_nirqs; i++) 776 hpetp->hp_dev[i].hd_hdwirq = hdp->hd_irq[i]; 777 778 hpet = hpetp->hp_hpet; 779 780 cap = readq(&hpet->hpet_cap); 781 782 ntimer = ((cap & HPET_NUM_TIM_CAP_MASK) >> HPET_NUM_TIM_CAP_SHIFT) + 1; 783 784 if (hpetp->hp_ntimer != ntimer) { 785 printk(KERN_WARNING "hpet: number irqs doesn't agree" 786 " with number of timers\n"); 787 kfree(hpetp); 788 return -ENODEV; 789 } 790 791 if (last) 792 last->hp_next = hpetp; 793 else 794 hpets = hpetp; 795 796 last = hpetp; 797 798 period = (cap & HPET_COUNTER_CLK_PERIOD_MASK) >> 799 HPET_COUNTER_CLK_PERIOD_SHIFT; /* fs, 10^-15 */ 800 temp = 1000000000000000uLL; /* 10^15 femtoseconds per second */ 801 temp += period >> 1; /* round */ 802 do_div(temp, period); 803 hpetp->hp_tick_freq = temp; /* ticks per second */ 804 805 printk(KERN_INFO "hpet%d: at MMIO 0x%lx, IRQ%s", 806 hpetp->hp_which, hdp->hd_phys_address, 807 hpetp->hp_ntimer > 1 ? "s" : ""); 808 for (i = 0; i < hpetp->hp_ntimer; i++) 809 printk("%s %d", i > 0 ? "," : "", hdp->hd_irq[i]); 810 printk("\n"); 811 812 printk(KERN_INFO "hpet%u: %u %d-bit timers, %Lu Hz\n", 813 hpetp->hp_which, hpetp->hp_ntimer, 814 cap & HPET_COUNTER_SIZE_MASK ? 64 : 32, hpetp->hp_tick_freq); 815 816 mcfg = readq(&hpet->hpet_config); 817 if ((mcfg & HPET_ENABLE_CNF_MASK) == 0) { 818 write_counter(0L, &hpet->hpet_mc); 819 mcfg |= HPET_ENABLE_CNF_MASK; 820 writeq(mcfg, &hpet->hpet_config); 821 } 822 823 for (i = 0, devp = hpetp->hp_dev; i < hpetp->hp_ntimer; i++, devp++) { 824 struct hpet_timer __iomem *timer; 825 826 timer = &hpet->hpet_timers[devp - hpetp->hp_dev]; 827 828 devp->hd_hpets = hpetp; 829 devp->hd_hpet = hpet; 830 devp->hd_timer = timer; 831 832 /* 833 * If the timer was reserved by platform code, 834 * then make timer unavailable for opens. 835 */ 836 if (hdp->hd_state & (1 << i)) { 837 devp->hd_flags = HPET_OPEN; 838 continue; 839 } 840 841 init_waitqueue_head(&devp->hd_waitqueue); 842 } 843 844 hpetp->hp_delta = hpet_calibrate(hpetp); 845 846 /* This clocksource driver currently only works on ia64 */ 847 #ifdef CONFIG_IA64 848 if (!hpet_clocksource) { 849 hpet_mctr = (void __iomem *)&hpetp->hp_hpet->hpet_mc; 850 CLKSRC_FSYS_MMIO_SET(clocksource_hpet.fsys_mmio, hpet_mctr); 851 clocksource_hpet.mult = clocksource_hz2mult(hpetp->hp_tick_freq, 852 clocksource_hpet.shift); 853 clocksource_register(&clocksource_hpet); 854 hpetp->hp_clocksource = &clocksource_hpet; 855 hpet_clocksource = &clocksource_hpet; 856 } 857 #endif 858 859 return 0; 860 } 861 862 static acpi_status hpet_resources(struct acpi_resource *res, void *data) 863 { 864 struct hpet_data *hdp; 865 acpi_status status; 866 struct acpi_resource_address64 addr; 867 868 hdp = data; 869 870 status = acpi_resource_to_address64(res, &addr); 871 872 if (ACPI_SUCCESS(status)) { 873 hdp->hd_phys_address = addr.minimum; 874 hdp->hd_address = ioremap(addr.minimum, addr.address_length); 875 876 if (hpet_is_known(hdp)) { 877 printk(KERN_DEBUG "%s: 0x%lx is busy\n", 878 __func__, hdp->hd_phys_address); 879 iounmap(hdp->hd_address); 880 return AE_ALREADY_EXISTS; 881 } 882 } else if (res->type == ACPI_RESOURCE_TYPE_FIXED_MEMORY32) { 883 struct acpi_resource_fixed_memory32 *fixmem32; 884 885 fixmem32 = &res->data.fixed_memory32; 886 if (!fixmem32) 887 return AE_NO_MEMORY; 888 889 hdp->hd_phys_address = fixmem32->address; 890 hdp->hd_address = ioremap(fixmem32->address, 891 HPET_RANGE_SIZE); 892 893 if (hpet_is_known(hdp)) { 894 printk(KERN_DEBUG "%s: 0x%lx is busy\n", 895 __func__, hdp->hd_phys_address); 896 iounmap(hdp->hd_address); 897 return AE_ALREADY_EXISTS; 898 } 899 } else if (res->type == ACPI_RESOURCE_TYPE_EXTENDED_IRQ) { 900 struct acpi_resource_extended_irq *irqp; 901 int i, irq; 902 903 irqp = &res->data.extended_irq; 904 905 for (i = 0; i < irqp->interrupt_count; i++) { 906 irq = acpi_register_gsi(irqp->interrupts[i], 907 irqp->triggering, irqp->polarity); 908 if (irq < 0) 909 return AE_ERROR; 910 911 hdp->hd_irq[hdp->hd_nirqs] = irq; 912 hdp->hd_nirqs++; 913 } 914 } 915 916 return AE_OK; 917 } 918 919 static int hpet_acpi_add(struct acpi_device *device) 920 { 921 acpi_status result; 922 struct hpet_data data; 923 924 memset(&data, 0, sizeof(data)); 925 926 result = 927 acpi_walk_resources(device->handle, METHOD_NAME__CRS, 928 hpet_resources, &data); 929 930 if (ACPI_FAILURE(result)) 931 return -ENODEV; 932 933 if (!data.hd_address || !data.hd_nirqs) { 934 printk("%s: no address or irqs in _CRS\n", __func__); 935 return -ENODEV; 936 } 937 938 return hpet_alloc(&data); 939 } 940 941 static int hpet_acpi_remove(struct acpi_device *device, int type) 942 { 943 /* XXX need to unregister clocksource, dealloc mem, etc */ 944 return -EINVAL; 945 } 946 947 static const struct acpi_device_id hpet_device_ids[] = { 948 {"PNP0103", 0}, 949 {"", 0}, 950 }; 951 MODULE_DEVICE_TABLE(acpi, hpet_device_ids); 952 953 static struct acpi_driver hpet_acpi_driver = { 954 .name = "hpet", 955 .ids = hpet_device_ids, 956 .ops = { 957 .add = hpet_acpi_add, 958 .remove = hpet_acpi_remove, 959 }, 960 }; 961 962 static struct miscdevice hpet_misc = { HPET_MINOR, "hpet", &hpet_fops }; 963 964 static int __init hpet_init(void) 965 { 966 int result; 967 968 result = misc_register(&hpet_misc); 969 if (result < 0) 970 return -ENODEV; 971 972 sysctl_header = register_sysctl_table(dev_root); 973 974 result = acpi_bus_register_driver(&hpet_acpi_driver); 975 if (result < 0) { 976 if (sysctl_header) 977 unregister_sysctl_table(sysctl_header); 978 misc_deregister(&hpet_misc); 979 return result; 980 } 981 982 return 0; 983 } 984 985 static void __exit hpet_exit(void) 986 { 987 acpi_bus_unregister_driver(&hpet_acpi_driver); 988 989 if (sysctl_header) 990 unregister_sysctl_table(sysctl_header); 991 misc_deregister(&hpet_misc); 992 993 return; 994 } 995 996 module_init(hpet_init); 997 module_exit(hpet_exit); 998 MODULE_AUTHOR("Bob Picco <Robert.Picco@hp.com>"); 999 MODULE_LICENSE("GPL"); 1000