LXR uboot/cpu/pxa/interrupts.c

   1/*
   2 * (C) Copyright 2002
   3 * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
   4 * Marius Groeger <mgroeger@sysgo.de>
   5 *
   6 * (C) Copyright 2002
   7 * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
   8 * Alex Zuepke <azu@sysgo.de>
   9 *
  10 * See file CREDITS for list of people who contributed to this
  11 * project.
  12 *
  13 * This program is free software; you can redistribute it and/or
  14 * modify it under the terms of the GNU General Public License as
  15 * published by the Free Software Foundation; either version 2 of
  16 * the License, or (at your option) any later version.
  17 *
  18 * This program is distributed in the hope that it will be useful,
  19 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  20 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  21 * GNU General Public License for more details.
  22 *
  23 * You should have received a copy of the GNU General Public License
  24 * along with this program; if not, write to the Free Software
  25 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  26 * MA 02111-1307 USA
  27 */
  28
  29#include <common.h>
  30#include <asm/arch/pxa-regs.h>
  31#include <div64.h>
  32
  33#ifdef CONFIG_USE_IRQ
  34#error: interrupts not implemented yet
  35#endif
  36
  37#if defined(CONFIG_PXA27X) || defined(CONFIG_CPU_MONAHANS)
  38#define TIMER_FREQ_HZ 3250000
  39#elif defined(CONFIG_PXA250)
  40#define TIMER_FREQ_HZ 3686400
  41#else
  42#error "Timer frequency unknown - please config PXA CPU type"
  43#endif
  44
  45static inline unsigned long long tick_to_time(unsigned long long tick)
  46{
  47        tick *= CONFIG_SYS_HZ;
  48        do_div(tick, TIMER_FREQ_HZ);
  49        return tick;
  50}
  51
  52static inline unsigned long long us_to_tick(unsigned long long us)
  53{
  54        us = us * TIMER_FREQ_HZ + 999999;
  55        do_div(us, 1000000);
  56        return us;
  57}
  58
  59int interrupt_init (void)
  60{
  61        /* nothing happens here - we don't setup any IRQs */
  62        return (0);
  63}
  64
  65void reset_timer (void)
  66{
  67        reset_timer_masked ();
  68}
  69
  70ulong get_timer (ulong base)
  71{
  72        return get_timer_masked () - base;
  73}
  74
  75void set_timer (ulong t)
  76{
  77        /* nop */
  78}
  79
  80void udelay (unsigned long usec)
  81{
  82        udelay_masked (usec);
  83}
  84
  85
  86void reset_timer_masked (void)
  87{
  88        OSCR = 0;
  89}
  90
  91ulong get_timer_masked (void)
  92{
  93        return tick_to_time(get_ticks());
  94}
  95
  96void udelay_masked (unsigned long usec)
  97{
  98        unsigned long long tmp;
  99        ulong tmo;
 100
 101        tmo = us_to_tick(usec);
 102        tmp = get_ticks() + tmo;        /* get current timestamp */
 103
 104        while (get_ticks() < tmp)       /* loop till event */
 105                 /*NOP*/;
 106
 107}
 108
 109/*
 110 * This function is derived from PowerPC code (read timebase as long long).
 111 * On ARM it just returns the timer value.
 112 */
 113unsigned long long get_ticks(void)
 114{
 115        return OSCR;
 116}
 117
 118/*
 119 * This function is derived from PowerPC code (timebase clock frequency).
 120 * On ARM it returns the number of timer ticks per second.
 121 */
 122ulong get_tbclk (void)
 123{
 124        ulong tbclk;
 125        tbclk = TIMER_FREQ_HZ;
 126        return tbclk;
 127}
 128