diff options
Diffstat (limited to 'arch/arm/mach-sunxi/sunxi.c')
| -rw-r--r-- | arch/arm/mach-sunxi/sunxi.c | 123 |
1 files changed, 123 insertions, 0 deletions
diff --git a/arch/arm/mach-sunxi/sunxi.c b/arch/arm/mach-sunxi/sunxi.c new file mode 100644 index 00000000..706ce353 --- /dev/null +++ b/arch/arm/mach-sunxi/sunxi.c @@ -0,0 +1,123 @@ +/* + * 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/irqchip.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> +#include <linux/of_platform.h> +#include <linux/io.h> + +#include <linux/clk/sunxi.h> + +#include <asm/mach/arch.h> +#include <asm/mach/map.h> +#include <asm/system_misc.h> + +#include "sunxi.h" + +#define SUN4I_WATCHDOG_CTRL_REG 0x00 +#define SUN4I_WATCHDOG_CTRL_RESTART (1 << 0) +#define SUN4I_WATCHDOG_MODE_REG 0x04 +#define SUN4I_WATCHDOG_MODE_ENABLE (1 << 0) +#define SUN4I_WATCHDOG_MODE_RESET_ENABLE (1 << 1) + +static void __iomem *wdt_base; + +static void sun4i_restart(char 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 struct of_device_id sunxi_restart_ids[] = { + { .compatible = "allwinner,sun4i-wdt", .data = sun4i_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 struct map_desc sunxi_io_desc[] __initdata = { + { + .virtual = (unsigned long) SUNXI_REGS_VIRT_BASE, + .pfn = __phys_to_pfn(SUNXI_REGS_PHYS_BASE), + .length = SUNXI_REGS_SIZE, + .type = MT_DEVICE, + }, +}; + +void __init sunxi_map_io(void) +{ + iotable_init(sunxi_io_desc, ARRAY_SIZE(sunxi_io_desc)); +} + +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-a13", + NULL, +}; + +DT_MACHINE_START(SUNXI_DT, "Allwinner A1X (Device Tree)") + .init_machine = sunxi_dt_init, + .map_io = sunxi_map_io, + .init_irq = irqchip_init, + .init_time = sunxi_timer_init, + .dt_compat = sunxi_board_dt_compat, +MACHINE_END |
