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/delay.h>
14 #include <linux/kernel.h>
15 #include <linux/init.h>
16 #include <linux/of_address.h>
17 #include <linux/of_irq.h>
18 #include <linux/of_platform.h>
20 #include <linux/sunxi_timer.h>
22 #include <linux/irqchip/sunxi.h>
24 #include <asm/hardware/vic.h>
26 #include <asm/mach/arch.h>
27 #include <asm/mach/map.h>
31 #define WATCHDOG_CTRL_REG 0x00
32 #define WATCHDOG_MODE_REG 0x04
34 static void __iomem
*wdt_base
;
36 static void sunxi_setup_restart(void)
38 struct device_node
*np
= of_find_compatible_node(NULL
, NULL
,
39 "allwinner,sunxi-wdt");
40 if (WARN(!np
, "unable to setup watchdog restart"))
43 wdt_base
= of_iomap(np
, 0);
44 WARN(!wdt_base
, "failed to map watchdog base address");
47 static void sunxi_restart(char mode
, const char *cmd
)
52 /* Enable timer and set reset bit in the watchdog */
53 writel(3, wdt_base
+ WATCHDOG_MODE_REG
);
54 writel(0xa57 << 1 | 1, wdt_base
+ WATCHDOG_CTRL_REG
);
57 writel(3, wdt_base
+ WATCHDOG_MODE_REG
);
61 static struct map_desc sunxi_io_desc
[] __initdata
= {
63 .virtual = (unsigned long) SUNXI_REGS_VIRT_BASE
,
64 .pfn
= __phys_to_pfn(SUNXI_REGS_PHYS_BASE
),
65 .length
= SUNXI_REGS_SIZE
,
70 void __init
sunxi_map_io(void)
72 iotable_init(sunxi_io_desc
, ARRAY_SIZE(sunxi_io_desc
));
75 static void __init
sunxi_dt_init(void)
77 sunxi_setup_restart();
79 of_platform_populate(NULL
, of_default_bus_match_table
, NULL
, NULL
);
82 static const char * const sunxi_board_dt_compat
[] = {
88 DT_MACHINE_START(SUNXI_DT
, "Allwinner A1X (Device Tree)")
89 .init_machine
= sunxi_dt_init
,
90 .map_io
= sunxi_map_io
,
91 .init_irq
= sunxi_init_irq
,
92 .handle_irq
= sunxi_handle_irq
,
93 .restart
= sunxi_restart
,
94 .timer
= &sunxi_timer
,
95 .dt_compat
= sunxi_board_dt_compat
,