LXR uboot/lib_sh/time.c

   1/*
   2 * (C) Copyright 2007-2008
   3 * Nobobuhiro Iwamatsu <iwamatsu@nigauri.org>
   4 *
   5 * (C) Copyright 2003
   6 * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
   7 *
   8 * See file CREDITS for list of people who contributed to this
   9 * project.
  10 *
  11 * This program is free software; you can redistribute it and/or
  12 * modify it under the terms of the GNU General Public License as
  13 * published by the Free Software Foundation; either version 2 of
  14 * the License, or (at your option) any later version.
  15 *
  16 * This program is distributed in the hope that it will be useful,
  17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19 * GNU General Public License for more details.
  20 *
  21 * You should have received a copy of the GNU General Public License
  22 * along with this program; if not, write to the Free Software
  23 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  24 * MA 02111-1307 USA
  25 */
  26
  27#include <common.h>
  28#include <asm/processor.h>
  29#include <asm/io.h>
  30
  31#define TMU_MAX_COUNTER (~0UL)
  32static int clk_adj = 1;
  33
  34static void tmu_timer_start (unsigned int timer)
  35{
  36        if (timer > 2)
  37                return;
  38        writeb(readb(TSTR) | (1 << timer), TSTR);
  39}
  40
  41static void tmu_timer_stop (unsigned int timer)
  42{
  43        if (timer > 2)
  44                return;
  45        writeb(readb(TSTR) & ~(1 << timer), TSTR);
  46}
  47
  48int timer_init (void)
  49{
  50        /* Divide clock by TMU_CLK_DIVIDER */
  51        u16 bit = 0;
  52
  53        switch (TMU_CLK_DIVIDER) {
  54        case 1024:
  55                bit = 4;
  56                break;
  57        case 256:
  58                bit = 3;
  59                break;
  60        case 64:
  61                bit = 2;
  62                break;
  63        case 16:
  64                bit = 1;
  65                break;
  66        case 4:
  67        default:
  68                bit = 0;
  69                break;
  70        }
  71        writew(readw(TCR0) | bit, TCR0);
  72
  73        /* Clock adjustment calc */
  74        clk_adj = (int)(1.0 / ((1.0 / CONFIG_SYS_HZ) * 1000000));
  75        if (clk_adj < 1)
  76                clk_adj = 1;
  77
  78        tmu_timer_stop(0);
  79        tmu_timer_start(0);
  80
  81        return 0;
  82}
  83
  84unsigned long long get_ticks (void)
  85{
  86        return 0 - readl(TCNT0);
  87}
  88
  89static unsigned long get_usec (void)
  90{
  91        return (0 - readl(TCNT0));
  92}
  93
  94void udelay (unsigned long usec)
  95{
  96        unsigned int start = get_usec();
  97        unsigned int end = start + (usec * clk_adj);
  98
  99        while (get_usec() < end)
 100                continue;
 101}
 102
 103unsigned long get_timer (unsigned long base)
 104{
 105        /* return msec */
 106        return ((get_usec() / clk_adj) / 1000) - base;
 107}
 108
 109void set_timer (unsigned long t)
 110{
 111        writel((0 - t), TCNT0);
 112}
 113
 114void reset_timer (void)
 115{
 116        tmu_timer_stop(0);
 117        set_timer (0);
 118        tmu_timer_start(0);
 119}
 120
 121unsigned long get_tbclk (void)
 122{
 123        return CONFIG_SYS_HZ;
 124}
 125