85 строки
2.1 KiB
C
85 строки
2.1 KiB
C
/*
|
|
* Copyright (c) 2011 Picochip Ltd., Jamie Iles
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License version 2 as
|
|
* published by the Free Software Foundation.
|
|
*
|
|
* All enquiries to support@picochip.com
|
|
*/
|
|
#include <linux/delay.h>
|
|
#include <linux/of.h>
|
|
#include <linux/of_address.h>
|
|
#include <linux/reboot.h>
|
|
|
|
#include <asm/mach/arch.h>
|
|
#include <asm/mach/map.h>
|
|
|
|
#define PHYS_TO_IO(x) (((x) & 0x00ffffff) | 0xfe000000)
|
|
#define PICOXCELL_PERIPH_BASE 0x80000000
|
|
#define PICOXCELL_PERIPH_LENGTH SZ_4M
|
|
|
|
#define WDT_CTRL_REG_EN_MASK (1 << 0)
|
|
#define WDT_CTRL_REG_OFFS (0x00)
|
|
#define WDT_TIMEOUT_REG_OFFS (0x04)
|
|
static void __iomem *wdt_regs;
|
|
|
|
/*
|
|
* The machine restart method can be called from an atomic context so we won't
|
|
* be able to ioremap the regs then.
|
|
*/
|
|
static void picoxcell_setup_restart(void)
|
|
{
|
|
struct device_node *np = of_find_compatible_node(NULL, NULL,
|
|
"snps,dw-apb-wdg");
|
|
if (WARN(!np, "unable to setup watchdog restart"))
|
|
return;
|
|
|
|
wdt_regs = of_iomap(np, 0);
|
|
WARN(!wdt_regs, "failed to remap watchdog regs");
|
|
}
|
|
|
|
static struct map_desc io_map __initdata = {
|
|
.virtual = PHYS_TO_IO(PICOXCELL_PERIPH_BASE),
|
|
.pfn = __phys_to_pfn(PICOXCELL_PERIPH_BASE),
|
|
.length = PICOXCELL_PERIPH_LENGTH,
|
|
.type = MT_DEVICE,
|
|
};
|
|
|
|
static void __init picoxcell_map_io(void)
|
|
{
|
|
iotable_init(&io_map, 1);
|
|
}
|
|
|
|
static void __init picoxcell_init_machine(void)
|
|
{
|
|
picoxcell_setup_restart();
|
|
}
|
|
|
|
static const char *picoxcell_dt_match[] = {
|
|
"picochip,pc3x2",
|
|
"picochip,pc3x3",
|
|
NULL
|
|
};
|
|
|
|
static void picoxcell_wdt_restart(enum reboot_mode mode, const char *cmd)
|
|
{
|
|
/*
|
|
* Configure the watchdog to reset with the shortest possible timeout
|
|
* and give it chance to do the reset.
|
|
*/
|
|
if (wdt_regs) {
|
|
writel_relaxed(WDT_CTRL_REG_EN_MASK, wdt_regs + WDT_CTRL_REG_OFFS);
|
|
writel_relaxed(0, wdt_regs + WDT_TIMEOUT_REG_OFFS);
|
|
/* No sleeping, possibly atomic. */
|
|
mdelay(500);
|
|
}
|
|
}
|
|
|
|
DT_MACHINE_START(PICOXCELL, "Picochip picoXcell")
|
|
.map_io = picoxcell_map_io,
|
|
.init_machine = picoxcell_init_machine,
|
|
.dt_compat = picoxcell_dt_match,
|
|
.restart = picoxcell_wdt_restart,
|
|
MACHINE_END
|