timer.c 2.1 KB

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  1. /*
  2. * SH-Mobile Timer
  3. *
  4. * Copyright (C) 2010 Magnus Damm
  5. * Copyright (C) 2002 - 2009 Paul Mundt
  6. *
  7. * This program is free software; you can redistribute it and/or modify
  8. * it under the terms of the GNU General Public License as published by
  9. * the Free Software Foundation; version 2 of the License.
  10. *
  11. * This program is distributed in the hope that it will be useful,
  12. * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13. * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  14. * GNU General Public License for more details.
  15. *
  16. * You should have received a copy of the GNU General Public License
  17. * along with this program; if not, write to the Free Software
  18. * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
  19. *
  20. */
  21. #include <linux/platform_device.h>
  22. #include <linux/delay.h>
  23. #include <asm/mach/time.h>
  24. #include <asm/smp_twd.h>
  25. void __init shmobile_setup_delay(unsigned int max_cpu_core_mhz,
  26. unsigned int mult, unsigned int div)
  27. {
  28. /* calculate a worst-case loops-per-jiffy value
  29. * based on maximum cpu core mhz setting and the
  30. * __delay() implementation in arch/arm/lib/delay.S
  31. *
  32. * this will result in a longer delay than expected
  33. * when the cpu core runs on lower frequencies.
  34. */
  35. unsigned int value = (1000000 * mult) / (HZ * div);
  36. if (!preset_lpj)
  37. preset_lpj = max_cpu_core_mhz * value;
  38. }
  39. static void __init shmobile_late_time_init(void)
  40. {
  41. /*
  42. * Make sure all compiled-in early timers register themselves.
  43. *
  44. * Run probe() for two "earlytimer" devices, these will be the
  45. * clockevents and clocksource devices respectively. In the event
  46. * that only a clockevents device is available, we -ENODEV on the
  47. * clocksource and the jiffies clocksource is used transparently
  48. * instead. No error handling is necessary here.
  49. */
  50. early_platform_driver_register_all("earlytimer");
  51. early_platform_driver_probe("earlytimer", 2, 0);
  52. }
  53. void __init shmobile_earlytimer_init(void)
  54. {
  55. late_time_init = shmobile_late_time_init;
  56. }
  57. static void __init shmobile_timer_init(void)
  58. {
  59. }
  60. struct sys_timer shmobile_timer = {
  61. .init = shmobile_timer_init,
  62. };