src/system/kernel/arch/ppc/arch_timer.cpp

   1 /*
   2 ** Copyright 2001, Travis Geiselbrecht. All rights reserved.
   3 ** Distributed under the terms of the NewOS License.
   4 */
   5
   6
   7 #include <boot/stage2.h>
   8 #include <kernel.h>
   9 #include <debug.h>
  10
  11 #include <timer.h>
  12 #include <arch/timer.h>
  13
  14
  15 static bigtime_t sTickRate;
  16
  17
  18 void
  19 arch_timer_set_hardware_timer(bigtime_t timeout)
  20 {
  21         bigtime_t new_val_64;
  22
  23         if(timeout < 1000)
  24                 timeout = 1000;
  25
  26         new_val_64 = (timeout * sTickRate) / 1000000;
  27
  28         asm("mtdec      %0" :: "r"((uint32)new_val_64));
  29 }
  30
  31
  32 void
  33 arch_timer_clear_hardware_timer()
  34 {
  35         asm("mtdec      %0" :: "r"(0x7fffffff));
  36 }
  37
  38
  39 int
  40 arch_init_timer(kernel_args *ka)
  41 {
  42         sTickRate = ka->arch_args.time_base_frequency;
  43
  44         return 0;
  45 }
  46