diff options
Diffstat (limited to 'drivers/watchdog/sunxi_wdt.c')
-rw-r--r-- | drivers/watchdog/sunxi_wdt.c | 136 |
1 files changed, 103 insertions, 33 deletions
diff --git a/drivers/watchdog/sunxi_wdt.c b/drivers/watchdog/sunxi_wdt.c index 60deb9d304c0..b62301e74e5f 100644 --- a/drivers/watchdog/sunxi_wdt.c +++ b/drivers/watchdog/sunxi_wdt.c @@ -21,25 +21,21 @@ #include <linux/kernel.h> #include <linux/module.h> #include <linux/moduleparam.h> +#include <linux/notifier.h> #include <linux/of.h> +#include <linux/of_device.h> #include <linux/platform_device.h> #include <linux/reboot.h> #include <linux/types.h> #include <linux/watchdog.h> -#include <asm/system_misc.h> - #define WDT_MAX_TIMEOUT 16 #define WDT_MIN_TIMEOUT 1 -#define WDT_MODE_TIMEOUT(n) ((n) << 3) -#define WDT_TIMEOUT_MASK WDT_MODE_TIMEOUT(0x0F) +#define WDT_TIMEOUT_MASK 0x0F -#define WDT_CTRL 0x00 #define WDT_CTRL_RELOAD ((1 << 0) | (0x0a57 << 1)) -#define WDT_MODE 0x04 #define WDT_MODE_EN (1 << 0) -#define WDT_MODE_RST_EN (1 << 1) #define DRV_NAME "sunxi-wdt" #define DRV_VERSION "1.0" @@ -47,14 +43,29 @@ static bool nowayout = WATCHDOG_NOWAYOUT; static unsigned int timeout = WDT_MAX_TIMEOUT; +/* + * This structure stores the register offsets for different variants + * of Allwinner's watchdog hardware. + */ +struct sunxi_wdt_reg { + u8 wdt_ctrl; + u8 wdt_cfg; + u8 wdt_mode; + u8 wdt_timeout_shift; + u8 wdt_reset_mask; + u8 wdt_reset_val; +}; + struct sunxi_wdt_dev { struct watchdog_device wdt_dev; void __iomem *wdt_base; + const struct sunxi_wdt_reg *wdt_regs; + struct notifier_block restart_handler; }; /* * wdt_timeout_map maps the watchdog timer interval value in seconds to - * the value of the register WDT_MODE bit 3:6 + * the value of the register WDT_MODE at bits .wdt_timeout_shift ~ +3 * * [timeout seconds] = register value * @@ -74,32 +85,51 @@ static const int wdt_timeout_map[] = { [16] = 0xB, /* 16s */ }; -static void __iomem *reboot_wdt_base; -static void sun4i_wdt_restart(enum reboot_mode mode, const char *cmd) +static int sunxi_restart_handle(struct notifier_block *this, unsigned long mode, + void *cmd) { - /* Enable timer and set reset bit in the watchdog */ - writel(WDT_MODE_EN | WDT_MODE_RST_EN, reboot_wdt_base + WDT_MODE); + struct sunxi_wdt_dev *sunxi_wdt = container_of(this, + struct sunxi_wdt_dev, + restart_handler); + void __iomem *wdt_base = sunxi_wdt->wdt_base; + const struct sunxi_wdt_reg *regs = sunxi_wdt->wdt_regs; + u32 val; + + /* Set system reset function */ + val = readl(wdt_base + regs->wdt_cfg); + val &= ~(regs->wdt_reset_mask); + val |= regs->wdt_reset_val; + writel(val, wdt_base + regs->wdt_cfg); + + /* Set lowest timeout and enable watchdog */ + val = readl(wdt_base + regs->wdt_mode); + val &= ~(WDT_TIMEOUT_MASK << regs->wdt_timeout_shift); + val |= WDT_MODE_EN; + writel(val, wdt_base + regs->wdt_mode); /* * Restart the watchdog. The default (and lowest) interval * value for the watchdog is 0.5s. */ - writel(WDT_CTRL_RELOAD, reboot_wdt_base + WDT_CTRL); + writel(WDT_CTRL_RELOAD, wdt_base + regs->wdt_ctrl); while (1) { mdelay(5); - writel(WDT_MODE_EN | WDT_MODE_RST_EN, - reboot_wdt_base + WDT_MODE); + val = readl(wdt_base + regs->wdt_mode); + val |= WDT_MODE_EN; + writel(val, wdt_base + regs->wdt_mode); } + return NOTIFY_DONE; } static int sunxi_wdt_ping(struct watchdog_device *wdt_dev) { struct sunxi_wdt_dev *sunxi_wdt = watchdog_get_drvdata(wdt_dev); void __iomem *wdt_base = sunxi_wdt->wdt_base; + const struct sunxi_wdt_reg *regs = sunxi_wdt->wdt_regs; - iowrite32(WDT_CTRL_RELOAD, wdt_base + WDT_CTRL); + writel(WDT_CTRL_RELOAD, wdt_base + regs->wdt_ctrl); return 0; } @@ -109,6 +139,7 @@ static int sunxi_wdt_set_timeout(struct watchdog_device *wdt_dev, { struct sunxi_wdt_dev *sunxi_wdt = watchdog_get_drvdata(wdt_dev); void __iomem *wdt_base = sunxi_wdt->wdt_base; + const struct sunxi_wdt_reg *regs = sunxi_wdt->wdt_regs; u32 reg; if (wdt_timeout_map[timeout] == 0) @@ -116,10 +147,10 @@ static int sunxi_wdt_set_timeout(struct watchdog_device *wdt_dev, sunxi_wdt->wdt_dev.timeout = timeout; - reg = ioread32(wdt_base + WDT_MODE); - reg &= ~WDT_TIMEOUT_MASK; - reg |= WDT_MODE_TIMEOUT(wdt_timeout_map[timeout]); - iowrite32(reg, wdt_base + WDT_MODE); + reg = readl(wdt_base + regs->wdt_mode); + reg &= ~(WDT_TIMEOUT_MASK << regs->wdt_timeout_shift); + reg |= wdt_timeout_map[timeout] << regs->wdt_timeout_shift; + writel(reg, wdt_base + regs->wdt_mode); sunxi_wdt_ping(wdt_dev); @@ -130,8 +161,9 @@ static int sunxi_wdt_stop(struct watchdog_device *wdt_dev) { struct sunxi_wdt_dev *sunxi_wdt = watchdog_get_drvdata(wdt_dev); void __iomem *wdt_base = sunxi_wdt->wdt_base; + const struct sunxi_wdt_reg *regs = sunxi_wdt->wdt_regs; - iowrite32(0, wdt_base + WDT_MODE); + writel(0, wdt_base + regs->wdt_mode); return 0; } @@ -141,6 +173,7 @@ static int sunxi_wdt_start(struct watchdog_device *wdt_dev) u32 reg; struct sunxi_wdt_dev *sunxi_wdt = watchdog_get_drvdata(wdt_dev); void __iomem *wdt_base = sunxi_wdt->wdt_base; + const struct sunxi_wdt_reg *regs = sunxi_wdt->wdt_regs; int ret; ret = sunxi_wdt_set_timeout(&sunxi_wdt->wdt_dev, @@ -148,9 +181,16 @@ static int sunxi_wdt_start(struct watchdog_device *wdt_dev) if (ret < 0) return ret; - reg = ioread32(wdt_base + WDT_MODE); - reg |= (WDT_MODE_RST_EN | WDT_MODE_EN); - iowrite32(reg, wdt_base + WDT_MODE); + /* Set system reset function */ + reg = readl(wdt_base + regs->wdt_cfg); + reg &= ~(regs->wdt_reset_mask); + reg |= ~(regs->wdt_reset_val); + writel(reg, wdt_base + regs->wdt_cfg); + + /* Enable watchdog */ + reg = readl(wdt_base + regs->wdt_mode); + reg |= WDT_MODE_EN; + writel(reg, wdt_base + regs->wdt_mode); return 0; } @@ -170,9 +210,35 @@ static const struct watchdog_ops sunxi_wdt_ops = { .set_timeout = sunxi_wdt_set_timeout, }; +static const struct sunxi_wdt_reg sun4i_wdt_reg = { + .wdt_ctrl = 0x00, + .wdt_cfg = 0x04, + .wdt_mode = 0x04, + .wdt_timeout_shift = 3, + .wdt_reset_mask = 0x02, + .wdt_reset_val = 0x02, +}; + +static const struct sunxi_wdt_reg sun6i_wdt_reg = { + .wdt_ctrl = 0x10, + .wdt_cfg = 0x14, + .wdt_mode = 0x18, + .wdt_timeout_shift = 4, + .wdt_reset_mask = 0x03, + .wdt_reset_val = 0x01, +}; + +static const struct of_device_id sunxi_wdt_dt_ids[] = { + { .compatible = "allwinner,sun4i-a10-wdt", .data = &sun4i_wdt_reg }, + { .compatible = "allwinner,sun6i-a31-wdt", .data = &sun6i_wdt_reg }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, sunxi_wdt_dt_ids); + static int sunxi_wdt_probe(struct platform_device *pdev) { struct sunxi_wdt_dev *sunxi_wdt; + const struct of_device_id *device; struct resource *res; int err; @@ -182,6 +248,12 @@ static int sunxi_wdt_probe(struct platform_device *pdev) platform_set_drvdata(pdev, sunxi_wdt); + device = of_match_device(sunxi_wdt_dt_ids, &pdev->dev); + if (!device) + return -ENODEV; + + sunxi_wdt->wdt_regs = device->data; + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); sunxi_wdt->wdt_base = devm_ioremap_resource(&pdev->dev, res); if (IS_ERR(sunxi_wdt->wdt_base)) @@ -205,8 +277,12 @@ static int sunxi_wdt_probe(struct platform_device *pdev) if (unlikely(err)) return err; - reboot_wdt_base = sunxi_wdt->wdt_base; - arm_pm_restart = sun4i_wdt_restart; + sunxi_wdt->restart_handler.notifier_call = sunxi_restart_handle; + sunxi_wdt->restart_handler.priority = 128; + err = register_restart_handler(&sunxi_wdt->restart_handler); + if (err) + dev_err(&pdev->dev, + "cannot register restart handler (err=%d)\n", err); dev_info(&pdev->dev, "Watchdog enabled (timeout=%d sec, nowayout=%d)", sunxi_wdt->wdt_dev.timeout, nowayout); @@ -218,7 +294,7 @@ static int sunxi_wdt_remove(struct platform_device *pdev) { struct sunxi_wdt_dev *sunxi_wdt = platform_get_drvdata(pdev); - arm_pm_restart = NULL; + unregister_restart_handler(&sunxi_wdt->restart_handler); watchdog_unregister_device(&sunxi_wdt->wdt_dev); watchdog_set_drvdata(&sunxi_wdt->wdt_dev, NULL); @@ -233,12 +309,6 @@ static void sunxi_wdt_shutdown(struct platform_device *pdev) sunxi_wdt_stop(&sunxi_wdt->wdt_dev); } -static const struct of_device_id sunxi_wdt_dt_ids[] = { - { .compatible = "allwinner,sun4i-a10-wdt" }, - { /* sentinel */ } -}; -MODULE_DEVICE_TABLE(of, sunxi_wdt_dt_ids); - static struct platform_driver sunxi_wdt_driver = { .probe = sunxi_wdt_probe, .remove = sunxi_wdt_remove, |