arch/arm/mach-rockchip/rk_timer.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * (C) Copyright 2015 Rockchip Electronics Co., Ltd
   4  */
   5
   6 #include <common.h>
   7 #include <asm/arch/timer.h>
   8 #include <asm/io.h>
   9 #include <linux/types.h>
  10
  11 struct rk_timer * const timer_ptr = (void *)CONFIG_SYS_TIMER_BASE;
  12
  13 static uint64_t rockchip_get_ticks(void)
  14 {
  15         uint64_t timebase_h, timebase_l;
  16
  17         timebase_l = readl(&timer_ptr->timer_curr_value0);
  18         timebase_h = readl(&timer_ptr->timer_curr_value1);
  19
  20         return timebase_h << 32 | timebase_l;
  21 }
  22
  23 static uint64_t usec_to_tick(unsigned int usec)
  24 {
  25         uint64_t tick = usec;
  26         tick *= CONFIG_SYS_TIMER_RATE / (1000 * 1000);
  27         return tick;
  28 }
  29
  30 void rockchip_udelay(unsigned int usec)
  31 {
  32         uint64_t tmp;
  33
  34         /* get timestamp */
  35         tmp = rockchip_get_ticks() + usec_to_tick(usec);
  36
  37         /* loop till event */
  38         while (rockchip_get_ticks() < tmp+1)
  39                 ;
  40 }
  41
  42 void rockchip_timer_init(void)
  43 {
  44         writel(0xffffffff, &timer_ptr->timer_load_count0);
  45         writel(0xffffffff, &timer_ptr->timer_load_count1);
  46         writel(1, &timer_ptr->timer_ctrl_reg);
  47 }