146 lines
3.7 KiB
C
146 lines
3.7 KiB
C
/*
|
|
* Device Tree support for Allwinner A1X SoCs
|
|
*
|
|
* Copyright (C) 2012 Maxime Ripard
|
|
*
|
|
* Maxime Ripard <maxime.ripard@free-electrons.com>
|
|
*
|
|
* This file is licensed under the terms of the GNU General Public
|
|
* License version 2. This program is licensed "as is" without any
|
|
* warranty of any kind, whether express or implied.
|
|
*/
|
|
|
|
#include <linux/clocksource.h>
|
|
#include <linux/delay.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/init.h>
|
|
#include <linux/of_address.h>
|
|
#include <linux/of_irq.h>
|
|
#include <linux/of_platform.h>
|
|
#include <linux/io.h>
|
|
#include <linux/reboot.h>
|
|
|
|
#include <linux/clk/sunxi.h>
|
|
|
|
#include <asm/mach/arch.h>
|
|
#include <asm/mach/map.h>
|
|
#include <asm/system_misc.h>
|
|
|
|
#define SUN4I_WATCHDOG_CTRL_REG 0x00
|
|
#define SUN4I_WATCHDOG_CTRL_RESTART BIT(0)
|
|
#define SUN4I_WATCHDOG_MODE_REG 0x04
|
|
#define SUN4I_WATCHDOG_MODE_ENABLE BIT(0)
|
|
#define SUN4I_WATCHDOG_MODE_RESET_ENABLE BIT(1)
|
|
|
|
#define SUN6I_WATCHDOG1_IRQ_REG 0x00
|
|
#define SUN6I_WATCHDOG1_CTRL_REG 0x10
|
|
#define SUN6I_WATCHDOG1_CTRL_RESTART BIT(0)
|
|
#define SUN6I_WATCHDOG1_CONFIG_REG 0x14
|
|
#define SUN6I_WATCHDOG1_CONFIG_RESTART BIT(0)
|
|
#define SUN6I_WATCHDOG1_CONFIG_IRQ BIT(1)
|
|
#define SUN6I_WATCHDOG1_MODE_REG 0x18
|
|
#define SUN6I_WATCHDOG1_MODE_ENABLE BIT(0)
|
|
|
|
static void __iomem *wdt_base;
|
|
|
|
static void sun4i_restart(enum reboot_mode mode, const char *cmd)
|
|
{
|
|
if (!wdt_base)
|
|
return;
|
|
|
|
/* Enable timer and set reset bit in the watchdog */
|
|
writel(SUN4I_WATCHDOG_MODE_ENABLE | SUN4I_WATCHDOG_MODE_RESET_ENABLE,
|
|
wdt_base + SUN4I_WATCHDOG_MODE_REG);
|
|
|
|
/*
|
|
* Restart the watchdog. The default (and lowest) interval
|
|
* value for the watchdog is 0.5s.
|
|
*/
|
|
writel(SUN4I_WATCHDOG_CTRL_RESTART, wdt_base + SUN4I_WATCHDOG_CTRL_REG);
|
|
|
|
while (1) {
|
|
mdelay(5);
|
|
writel(SUN4I_WATCHDOG_MODE_ENABLE | SUN4I_WATCHDOG_MODE_RESET_ENABLE,
|
|
wdt_base + SUN4I_WATCHDOG_MODE_REG);
|
|
}
|
|
}
|
|
|
|
static void sun6i_restart(enum reboot_mode mode, const char *cmd)
|
|
{
|
|
if (!wdt_base)
|
|
return;
|
|
|
|
/* Disable interrupts */
|
|
writel(0, wdt_base + SUN6I_WATCHDOG1_IRQ_REG);
|
|
|
|
/* We want to disable the IRQ and just reset the whole system */
|
|
writel(SUN6I_WATCHDOG1_CONFIG_RESTART,
|
|
wdt_base + SUN6I_WATCHDOG1_CONFIG_REG);
|
|
|
|
/* Enable timer. The default and lowest interval value is 0.5s */
|
|
writel(SUN6I_WATCHDOG1_MODE_ENABLE,
|
|
wdt_base + SUN6I_WATCHDOG1_MODE_REG);
|
|
|
|
/* Restart the watchdog. */
|
|
writel(SUN6I_WATCHDOG1_CTRL_RESTART,
|
|
wdt_base + SUN6I_WATCHDOG1_CTRL_REG);
|
|
|
|
while (1) {
|
|
mdelay(5);
|
|
writel(SUN6I_WATCHDOG1_MODE_ENABLE,
|
|
wdt_base + SUN6I_WATCHDOG1_MODE_REG);
|
|
}
|
|
}
|
|
|
|
static struct of_device_id sunxi_restart_ids[] = {
|
|
{ .compatible = "allwinner,sun4i-wdt", .data = sun4i_restart },
|
|
{ .compatible = "allwinner,sun6i-wdt", .data = sun6i_restart },
|
|
{ /*sentinel*/ }
|
|
};
|
|
|
|
static void sunxi_setup_restart(void)
|
|
{
|
|
const struct of_device_id *of_id;
|
|
struct device_node *np;
|
|
|
|
np = of_find_matching_node(NULL, sunxi_restart_ids);
|
|
if (WARN(!np, "unable to setup watchdog restart"))
|
|
return;
|
|
|
|
wdt_base = of_iomap(np, 0);
|
|
WARN(!wdt_base, "failed to map watchdog base address");
|
|
|
|
of_id = of_match_node(sunxi_restart_ids, np);
|
|
WARN(!of_id, "restart function not available");
|
|
|
|
arm_pm_restart = of_id->data;
|
|
}
|
|
|
|
static void __init sunxi_timer_init(void)
|
|
{
|
|
sunxi_init_clocks();
|
|
clocksource_of_init();
|
|
}
|
|
|
|
static void __init sunxi_dt_init(void)
|
|
{
|
|
sunxi_setup_restart();
|
|
|
|
of_platform_populate(NULL, of_default_bus_match_table, NULL, NULL);
|
|
}
|
|
|
|
static const char * const sunxi_board_dt_compat[] = {
|
|
"allwinner,sun4i-a10",
|
|
"allwinner,sun5i-a10s",
|
|
"allwinner,sun5i-a13",
|
|
"allwinner,sun6i-a31",
|
|
"allwinner,sun7i-a20",
|
|
NULL,
|
|
};
|
|
|
|
DT_MACHINE_START(SUNXI_DT, "Allwinner A1X (Device Tree)")
|
|
.init_machine = sunxi_dt_init,
|
|
.init_time = sunxi_timer_init,
|
|
.dt_compat = sunxi_board_dt_compat,
|
|
MACHINE_END
|