LXR uboot/arch/arm/cpu/armv7/vf610/timer.c

   1// SPDX-License-Identifier: GPL-2.0+
   2/*
   3 * Copyright 2013 Freescale Semiconductor, Inc.
   4 */
   5
   6#include <common.h>
   7#include <asm/io.h>
   8#include <div64.h>
   9#include <asm/arch/imx-regs.h>
  10#include <asm/arch/clock.h>
  11
  12static struct pit_reg *cur_pit = (struct pit_reg *)PIT_BASE_ADDR;
  13
  14DECLARE_GLOBAL_DATA_PTR;
  15
  16#define TIMER_LOAD_VAL  0xffffffff
  17
  18static inline unsigned long long tick_to_time(unsigned long long tick)
  19{
  20        tick *= CONFIG_SYS_HZ;
  21        do_div(tick, mxc_get_clock(MXC_IPG_CLK));
  22
  23        return tick;
  24}
  25
  26static inline unsigned long long us_to_tick(unsigned long long usec)
  27{
  28        usec = usec * mxc_get_clock(MXC_IPG_CLK)  + 999999;
  29        do_div(usec, 1000000);
  30
  31        return usec;
  32}
  33
  34int timer_init(void)
  35{
  36        __raw_writel(0, &cur_pit->mcr);
  37
  38        __raw_writel(TIMER_LOAD_VAL, &cur_pit->ldval1);
  39        __raw_writel(0, &cur_pit->tctrl1);
  40        __raw_writel(1, &cur_pit->tctrl1);
  41
  42        gd->arch.tbl = 0;
  43        gd->arch.tbu = 0;
  44
  45        return 0;
  46}
  47
  48unsigned long long get_ticks(void)
  49{
  50        ulong now = TIMER_LOAD_VAL - __raw_readl(&cur_pit->cval1);
  51
  52        /* increment tbu if tbl has rolled over */
  53        if (now < gd->arch.tbl)
  54                gd->arch.tbu++;
  55        gd->arch.tbl = now;
  56
  57        return (((unsigned long long)gd->arch.tbu) << 32) | gd->arch.tbl;
  58}
  59
  60ulong get_timer(ulong base)
  61{
  62        return tick_to_time(get_ticks()) - base;
  63}
  64
  65/* delay x useconds AND preserve advance timstamp value */
  66void __udelay(unsigned long usec)
  67{
  68        unsigned long long start;
  69        ulong tmo;
  70
  71        start = get_ticks();                    /* get current timestamp */
  72        tmo = us_to_tick(usec);                 /* convert usecs to ticks */
  73        while ((get_ticks() - start) < tmo)
  74                ;                               /* loop till time has passed */
  75}
  76
  77/*
  78 * This function is derived from PowerPC code (timebase clock frequency).
  79 * On ARM it returns the number of timer ticks per second.
  80 */
  81ulong get_tbclk(void)
  82{
  83        return mxc_get_clock(MXC_IPG_CLK);
  84}
  85