Commit | Line | Data |
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3b52634f MR |
1 | /* |
2 | * Device Tree support for Allwinner A1X SoCs | |
3 | * | |
4 | * Copyright (C) 2012 Maxime Ripard | |
5 | * | |
6 | * Maxime Ripard <maxime.ripard@free-electrons.com> | |
7 | * | |
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. | |
11 | */ | |
12 | ||
5e51651d | 13 | #include <linux/delay.h> |
3b52634f MR |
14 | #include <linux/kernel.h> |
15 | #include <linux/init.h> | |
67bea88d | 16 | #include <linux/of_address.h> |
3b52634f MR |
17 | #include <linux/of_irq.h> |
18 | #include <linux/of_platform.h> | |
19 | #include <linux/io.h> | |
20 | #include <linux/sunxi_timer.h> | |
21 | ||
22 | #include <linux/irqchip/sunxi.h> | |
23 | ||
3b52634f MR |
24 | #include <asm/mach/arch.h> |
25 | #include <asm/mach/map.h> | |
26 | ||
27 | #include "sunxi.h" | |
28 | ||
67bea88d | 29 | #define WATCHDOG_CTRL_REG 0x00 |
b60decad | 30 | #define WATCHDOG_CTRL_RESTART (1 << 0) |
67bea88d | 31 | #define WATCHDOG_MODE_REG 0x04 |
b60decad MR |
32 | #define WATCHDOG_MODE_ENABLE (1 << 0) |
33 | #define WATCHDOG_MODE_RESET_ENABLE (1 << 1) | |
67bea88d MR |
34 | |
35 | static void __iomem *wdt_base; | |
36 | ||
37 | static void sunxi_setup_restart(void) | |
38 | { | |
39 | struct device_node *np = of_find_compatible_node(NULL, NULL, | |
40 | "allwinner,sunxi-wdt"); | |
41 | if (WARN(!np, "unable to setup watchdog restart")) | |
42 | return; | |
43 | ||
44 | wdt_base = of_iomap(np, 0); | |
45 | WARN(!wdt_base, "failed to map watchdog base address"); | |
46 | } | |
47 | ||
48 | static void sunxi_restart(char mode, const char *cmd) | |
49 | { | |
50 | if (!wdt_base) | |
51 | return; | |
52 | ||
53 | /* Enable timer and set reset bit in the watchdog */ | |
b60decad MR |
54 | writel(WATCHDOG_MODE_ENABLE | WATCHDOG_MODE_RESET_ENABLE, |
55 | wdt_base + WATCHDOG_MODE_REG); | |
56 | ||
57 | /* | |
58 | * Restart the watchdog. The default (and lowest) interval | |
59 | * value for the watchdog is 0.5s. | |
60 | */ | |
61 | writel(WATCHDOG_CTRL_RESTART, wdt_base + WATCHDOG_CTRL_REG); | |
62 | ||
63 | while (1) { | |
67bea88d | 64 | mdelay(5); |
b60decad MR |
65 | writel(WATCHDOG_MODE_ENABLE | WATCHDOG_MODE_RESET_ENABLE, |
66 | wdt_base + WATCHDOG_MODE_REG); | |
67bea88d MR |
67 | } |
68 | } | |
69 | ||
3b52634f MR |
70 | static struct map_desc sunxi_io_desc[] __initdata = { |
71 | { | |
72 | .virtual = (unsigned long) SUNXI_REGS_VIRT_BASE, | |
73 | .pfn = __phys_to_pfn(SUNXI_REGS_PHYS_BASE), | |
74 | .length = SUNXI_REGS_SIZE, | |
75 | .type = MT_DEVICE, | |
76 | }, | |
77 | }; | |
78 | ||
79 | void __init sunxi_map_io(void) | |
80 | { | |
81 | iotable_init(sunxi_io_desc, ARRAY_SIZE(sunxi_io_desc)); | |
82 | } | |
83 | ||
84 | static void __init sunxi_dt_init(void) | |
85 | { | |
67bea88d MR |
86 | sunxi_setup_restart(); |
87 | ||
3b52634f MR |
88 | of_platform_populate(NULL, of_default_bus_match_table, NULL, NULL); |
89 | } | |
90 | ||
91 | static const char * const sunxi_board_dt_compat[] = { | |
43880f70 MR |
92 | "allwinner,sun4i-a10", |
93 | "allwinner,sun5i-a13", | |
3b52634f MR |
94 | NULL, |
95 | }; | |
96 | ||
97 | DT_MACHINE_START(SUNXI_DT, "Allwinner A1X (Device Tree)") | |
98 | .init_machine = sunxi_dt_init, | |
99 | .map_io = sunxi_map_io, | |
100 | .init_irq = sunxi_init_irq, | |
101 | .handle_irq = sunxi_handle_irq, | |
67bea88d | 102 | .restart = sunxi_restart, |
1c2584c3 | 103 | .init_time = &sunxi_timer_init, |
3b52634f MR |
104 | .dt_compat = sunxi_board_dt_compat, |
105 | MACHINE_END |