2 * Device Tree support for Allwinner A1X SoCs
4 * Copyright (C) 2012 Maxime Ripard
6 * Maxime Ripard <maxime.ripard@free-electrons.com>
8 * This file is licensed under the terms of the GNU General Public
9 * License version 2. This program is licensed "as is" without any
10 * warranty of any kind, whether express or implied.
13 #include <linux/clk-provider.h>
14 #include <linux/clocksource.h>
15 #include <linux/delay.h>
16 #include <linux/kernel.h>
17 #include <linux/init.h>
18 #include <linux/of_address.h>
19 #include <linux/of_irq.h>
20 #include <linux/of_platform.h>
22 #include <linux/reboot.h>
24 #include <asm/mach/arch.h>
25 #include <asm/mach/map.h>
26 #include <asm/system_misc.h>
28 #define SUN4I_WATCHDOG_CTRL_REG 0x00
29 #define SUN4I_WATCHDOG_CTRL_RESTART BIT(0)
30 #define SUN4I_WATCHDOG_MODE_REG 0x04
31 #define SUN4I_WATCHDOG_MODE_ENABLE BIT(0)
32 #define SUN4I_WATCHDOG_MODE_RESET_ENABLE BIT(1)
34 #define SUN6I_WATCHDOG1_IRQ_REG 0x00
35 #define SUN6I_WATCHDOG1_CTRL_REG 0x10
36 #define SUN6I_WATCHDOG1_CTRL_RESTART BIT(0)
37 #define SUN6I_WATCHDOG1_CONFIG_REG 0x14
38 #define SUN6I_WATCHDOG1_CONFIG_RESTART BIT(0)
39 #define SUN6I_WATCHDOG1_CONFIG_IRQ BIT(1)
40 #define SUN6I_WATCHDOG1_MODE_REG 0x18
41 #define SUN6I_WATCHDOG1_MODE_ENABLE BIT(0)
43 static void __iomem *wdt_base;
45 static void sun4i_restart(enum reboot_mode mode, const char *cmd)
50 /* Enable timer and set reset bit in the watchdog */
51 writel(SUN4I_WATCHDOG_MODE_ENABLE | SUN4I_WATCHDOG_MODE_RESET_ENABLE,
52 wdt_base + SUN4I_WATCHDOG_MODE_REG);
55 * Restart the watchdog. The default (and lowest) interval
56 * value for the watchdog is 0.5s.
58 writel(SUN4I_WATCHDOG_CTRL_RESTART, wdt_base + SUN4I_WATCHDOG_CTRL_REG);
62 writel(SUN4I_WATCHDOG_MODE_ENABLE | SUN4I_WATCHDOG_MODE_RESET_ENABLE,
63 wdt_base + SUN4I_WATCHDOG_MODE_REG);
67 static struct of_device_id sunxi_restart_ids[] = {
68 { .compatible = "allwinner,sun4i-a10-wdt" },
72 static void sunxi_setup_restart(void)
74 struct device_node *np;
76 np = of_find_matching_node(NULL, sunxi_restart_ids);
77 if (WARN(!np, "unable to setup watchdog restart"))
80 wdt_base = of_iomap(np, 0);
81 WARN(!wdt_base, "failed to map watchdog base address");
84 static void __init sunxi_dt_init(void)
86 sunxi_setup_restart();
88 of_platform_populate(NULL, of_default_bus_match_table, NULL, NULL);
91 static const char * const sunxi_board_dt_compat[] = {
92 "allwinner,sun4i-a10",
93 "allwinner,sun5i-a10s",
94 "allwinner,sun5i-a13",
98 DT_MACHINE_START(SUNXI_DT, "Allwinner A1X (Device Tree)")
99 .init_machine = sunxi_dt_init,
100 .dt_compat = sunxi_board_dt_compat,
101 .restart = sun4i_restart,
104 static const char * const sun6i_board_dt_compat[] = {
105 "allwinner,sun6i-a31",
109 extern void __init sun6i_reset_init(void);
110 static void __init sun6i_timer_init(void)
113 if (IS_ENABLED(CONFIG_RESET_CONTROLLER))
115 clocksource_of_init();
118 DT_MACHINE_START(SUN6I_DT, "Allwinner sun6i (A31) Family")
119 .init_time = sun6i_timer_init,
120 .dt_compat = sun6i_board_dt_compat,
123 static const char * const sun7i_board_dt_compat[] = {
124 "allwinner,sun7i-a20",
128 DT_MACHINE_START(SUN7I_DT, "Allwinner sun7i (A20) Family")
129 .init_machine = sunxi_dt_init,
130 .dt_compat = sun7i_board_dt_compat,
131 .restart = sun4i_restart,