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/*
* (C) Copyright 2002
* Sysgo Real-Time Solutions, GmbH <www.elinos.com>
* Marius Groeger <mgroeger@sysgo.de>
*
* (C) Copyright 2002
* Sysgo Real-Time Solutions, GmbH <www.elinos.com>
* Alex Zuepke <azu@sysgo.de>
*
* (C) Copyright 2002
* Gary Jennejohn, DENX Software Engineering, <gj@denx.de>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of
* the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
*/
#include <common.h>
#include <init.h>
#include <clock.h>
#include <restart.h>
#include <mach/hardware.h>
#include <mach/at91rm9200_st.h>
#include <io.h>
static void __iomem *st = IOMEM(AT91RM9200_BASE_ST);
/*
* The ST_CRTR is updated asynchronously to the master clock ... but
* the updates as seen by the CPU don't seem to be strictly monotonic.
* Waiting until we read the same value twice avoids glitching.
*/
static uint64_t at91rm9200_clocksource_read(void)
{
unsigned long x1, x2;
x1 = readl(st + AT91RM9200_ST_CRTR);
do {
x2 = readl(st + AT91RM9200_ST_CRTR);
if (x1 == x2)
break;
x1 = x2;
} while (1);
return x1;
}
static struct clocksource cs = {
.mask = CLOCKSOURCE_MASK(20),
.read = at91rm9200_clocksource_read,
.shift = 10,
};
static int clocksource_init (void)
{
/* The 32KiHz "Slow Clock" (tick every 30517.58 nanoseconds) is used
* directly for the clocksource and all clockevents, after adjusting
* its prescaler from the 1 Hz default.
*/
writel(1, st + AT91RM9200_ST_RTMR);
cs.mult = clocksource_hz2mult(AT91_SLOW_CLOCK, cs.shift);
return init_clock(&cs);
}
core_initcall(clocksource_init);
/*
* Reset the cpu through the reset controller
*/
static void __noreturn at91rm9200_restart_soc(struct restart_handler *rst)
{
/*
* Perform a hardware reset with the use of the Watchdog timer.
*/
writel(AT91RM9200_ST_RSTEN | AT91RM9200_ST_EXTEN | 1, st + AT91RM9200_ST_WDMR);
writel(AT91RM9200_ST_WDRST, st + AT91RM9200_ST_CR);
/* Not reached */
hang();
}
static int restart_register_feature(void)
{
restart_handler_register_fn("soc-wdt", at91rm9200_restart_soc);
return 0;
}
coredevice_initcall(restart_register_feature);
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