arch/arm/mach-bcmring/timer.c

   1 /*****************************************************************************
   2 * Copyright 2003 - 2008 Broadcom Corporation.  All rights reserved.
   3 *
   4 * Unless you and Broadcom execute a separate written software license
   5 * agreement governing use of this software, this software is licensed to you
   6 * under the terms of the GNU General Public License version 2, available at
   7 * http://www.broadcom.com/licenses/GPLv2.php (the "GPL").
   8 *
   9 * Notwithstanding the above, under no circumstances may you combine this
  10 * software in any way with any other Broadcom software provided under a
  11 * license other than the GPL, without Broadcom's express prior written
  12 * consent.
  13 *****************************************************************************/
  14
  15 #include <linux/version.h>
  16 #include <linux/types.h>
  17 #include <linux/module.h>
  18 #include <csp/tmrHw.h>
  19
  20 #include <mach/timer.h>
  21 /* The core.c file initializes timers 1 and 3 as a linux clocksource. */
  22 /* The real time clock should probably be the real linux clocksource. */
  23 /* In the meantime, this file should agree with core.c as to the */
  24 /* profiling timer. If the clocksource is moved to rtc later, then */
  25 /* we can init the profiling timer here instead. */
  26
  27 /* Timer 1 provides 25MHz resolution syncrhonized to scheduling and APM timing */
  28 /* Timer 3 provides bus freqeuncy sychronized to ACLK, but spread spectrum will */
  29 /* affect synchronization with scheduling and APM timing. */
  30
  31 #define PROF_TIMER 1
  32
  33 timer_tick_rate_t timer_get_tick_rate(void)
  34 {
  35         return tmrHw_getCountRate(PROF_TIMER);
  36 }
  37
  38 timer_tick_count_t timer_get_tick_count(void)
  39 {
  40         return tmrHw_GetCurrentCount(PROF_TIMER);       /* change downcounter to upcounter */
  41 }
  42
  43 timer_msec_t timer_ticks_to_msec(timer_tick_count_t ticks)
  44 {
  45         static int tickRateMsec;
  46
  47         if (tickRateMsec == 0) {
  48                 tickRateMsec = timer_get_tick_rate() / 1000;
  49         }
  50
  51         return ticks / tickRateMsec;
  52 }
  53
  54 timer_msec_t timer_get_msec(void)
  55 {
  56         return timer_ticks_to_msec(timer_get_tick_count());
  57 }
  58
  59 EXPORT_SYMBOL(timer_get_tick_count);
  60 EXPORT_SYMBOL(timer_ticks_to_msec);
  61 EXPORT_SYMBOL(timer_get_tick_rate);
  62 EXPORT_SYMBOL(timer_get_msec);