From 8740f71d7f4f0400cd8c42e6584155024119d77e Mon Sep 17 00:00:00 2001 From: Banajit Goswami Date: Thu, 20 May 2010 11:58:24 +0100 Subject: watchdog: s3c2410_wdt - Add extra option to include watchdog for Samsung SoCs This patch adds HAVE_S3C2410_WATCHDOG to control inclusion of watchdog driver for Samsung SoCs. This option will help to include the driver only for the necessary machines and not for all for any given arch. Signed-off-by: Banajit Goswami Signed-off-by: Kukjin Kim Signed-off-by: Ben Dooks Signed-off-by: Wim Van Sebroeck --- drivers/watchdog/Kconfig | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-) (limited to 'drivers/watchdog/Kconfig') diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig index b87ba23442d2..c57ecffe0085 100644 --- a/drivers/watchdog/Kconfig +++ b/drivers/watchdog/Kconfig @@ -145,13 +145,19 @@ config KS8695_WATCHDOG Watchdog timer embedded into KS8695 processor. This will reboot your system when the timeout is reached. +config HAVE_S3C2410_WATCHDOG + bool + help + This will include watchdog timer support for Samsung SoCs. If + you want to include watchdog support for any machine, kindly + select this in the respective mach-XXXX/Kconfig file. + config S3C2410_WATCHDOG tristate "S3C2410 Watchdog" - depends on ARCH_S3C2410 + depends on ARCH_S3C2410 || HAVE_S3C2410_WATCHDOG help - Watchdog timer block in the Samsung S3C2410 chips. This will - reboot the system when the timer expires with the watchdog - enabled. + Watchdog timer block in the Samsung SoCs. This will reboot + the system when the timer expires with the watchdog enabled. The driver is limited by the speed of the system's PCLK signal, so with reasonably fast systems (PCLK around 50-66MHz) -- cgit v1.2.3 From bb2fd8a844d3a9209599b5fb694b30ac46a56ef0 Mon Sep 17 00:00:00 2001 From: Wolfram Sang Date: Thu, 29 Apr 2010 10:03:17 +0200 Subject: watchdog: Driver for the watchdog timer on Freescale IMX2 (and later) processors. This is the driver for the hardware watchdog on the Freescale IMX2 and later processors. Signed-off-by: Wolfram Sang Cc: Vladimir Zapolskiy Cc: Sascha Hauer Tested-by: Juergen Beisert Signed-off-by: Wim Van Sebroeck --- drivers/watchdog/Kconfig | 12 ++ drivers/watchdog/Makefile | 1 + drivers/watchdog/imx2_wdt.c | 358 ++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 371 insertions(+) create mode 100644 drivers/watchdog/imx2_wdt.c (limited to 'drivers/watchdog/Kconfig') diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig index c57ecffe0085..afcfacc9bbe2 100644 --- a/drivers/watchdog/Kconfig +++ b/drivers/watchdog/Kconfig @@ -312,6 +312,18 @@ config MAX63XX_WATCHDOG help Support for memory mapped max63{69,70,71,72,73,74} watchdog timer. +config IMX2_WDT + tristate "IMX2+ Watchdog" + depends on ARCH_MX2 || ARCH_MX25 || ARCH_MX3 || ARCH_MX5 + help + This is the driver for the hardware watchdog + on the Freescale IMX2 and later processors. + If you have one of these processors and wish to have + watchdog support enabled, say Y, otherwise say N. + + To compile this driver as a module, choose M here: the + module will be called imx2_wdt. + # AVR32 Architecture config AT32AP700X_WDT diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile index 5e3cb95bb0e9..72f3e2073f8e 100644 --- a/drivers/watchdog/Makefile +++ b/drivers/watchdog/Makefile @@ -47,6 +47,7 @@ obj-$(CONFIG_STMP3XXX_WATCHDOG) += stmp3xxx_wdt.o obj-$(CONFIG_NUC900_WATCHDOG) += nuc900_wdt.o obj-$(CONFIG_ADX_WATCHDOG) += adx_wdt.o obj-$(CONFIG_TS72XX_WATCHDOG) += ts72xx_wdt.o +obj-$(CONFIG_IMX2_WDT) += imx2_wdt.o # AVR32 Architecture obj-$(CONFIG_AT32AP700X_WDT) += at32ap700x_wdt.o diff --git a/drivers/watchdog/imx2_wdt.c b/drivers/watchdog/imx2_wdt.c new file mode 100644 index 000000000000..ea25885781bb --- /dev/null +++ b/drivers/watchdog/imx2_wdt.c @@ -0,0 +1,358 @@ +/* + * Watchdog driver for IMX2 and later processors + * + * Copyright (C) 2010 Wolfram Sang, Pengutronix e.K. + * + * some parts adapted by similar drivers from Darius Augulis and Vladimir + * Zapolskiy, additional improvements by Wim Van Sebroeck. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published by + * the Free Software Foundation. + * + * NOTE: MX1 has a slightly different Watchdog than MX2 and later: + * + * MX1: MX2+: + * ---- ----- + * Registers: 32-bit 16-bit + * Stopable timer: Yes No + * Need to enable clk: No Yes + * Halt on suspend: Manual Can be automatic + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define DRIVER_NAME "imx2-wdt" + +#define IMX2_WDT_WCR 0x00 /* Control Register */ +#define IMX2_WDT_WCR_WT (0xFF << 8) /* -> Watchdog Timeout Field */ +#define IMX2_WDT_WCR_WRE (1 << 3) /* -> WDOG Reset Enable */ +#define IMX2_WDT_WCR_WDE (1 << 2) /* -> Watchdog Enable */ + +#define IMX2_WDT_WSR 0x02 /* Service Register */ +#define IMX2_WDT_SEQ1 0x5555 /* -> service sequence 1 */ +#define IMX2_WDT_SEQ2 0xAAAA /* -> service sequence 2 */ + +#define IMX2_WDT_MAX_TIME 128 +#define IMX2_WDT_DEFAULT_TIME 60 /* in seconds */ + +#define WDOG_SEC_TO_COUNT(s) ((s * 2 - 1) << 8) + +#define IMX2_WDT_STATUS_OPEN 0 +#define IMX2_WDT_STATUS_STARTED 1 +#define IMX2_WDT_EXPECT_CLOSE 2 + +static struct { + struct clk *clk; + void __iomem *base; + unsigned timeout; + unsigned long status; + struct timer_list timer; /* Pings the watchdog when closed */ +} imx2_wdt; + +static struct miscdevice imx2_wdt_miscdev; + +static int nowayout = WATCHDOG_NOWAYOUT; +module_param(nowayout, int, 0); +MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" + __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); + + +static unsigned timeout = IMX2_WDT_DEFAULT_TIME; +module_param(timeout, uint, 0); +MODULE_PARM_DESC(timeout, "Watchdog timeout in seconds (default=" + __MODULE_STRING(IMX2_WDT_DEFAULT_TIME) ")"); + +static const struct watchdog_info imx2_wdt_info = { + .identity = "imx2+ watchdog", + .options = WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE, +}; + +static inline void imx2_wdt_setup(void) +{ + u16 val = __raw_readw(imx2_wdt.base + IMX2_WDT_WCR); + + /* Strip the old watchdog Time-Out value */ + val &= ~IMX2_WDT_WCR_WT; + /* Generate reset if WDOG times out */ + val &= ~IMX2_WDT_WCR_WRE; + /* Keep Watchdog Disabled */ + val &= ~IMX2_WDT_WCR_WDE; + /* Set the watchdog's Time-Out value */ + val |= WDOG_SEC_TO_COUNT(imx2_wdt.timeout); + + __raw_writew(val, imx2_wdt.base + IMX2_WDT_WCR); + + /* enable the watchdog */ + val |= IMX2_WDT_WCR_WDE; + __raw_writew(val, imx2_wdt.base + IMX2_WDT_WCR); +} + +static inline void imx2_wdt_ping(void) +{ + __raw_writew(IMX2_WDT_SEQ1, imx2_wdt.base + IMX2_WDT_WSR); + __raw_writew(IMX2_WDT_SEQ2, imx2_wdt.base + IMX2_WDT_WSR); +} + +static void imx2_wdt_timer_ping(unsigned long arg) +{ + /* ping it every imx2_wdt.timeout / 2 seconds to prevent reboot */ + imx2_wdt_ping(); + mod_timer(&imx2_wdt.timer, jiffies + imx2_wdt.timeout * HZ / 2); +} + +static void imx2_wdt_start(void) +{ + if (!test_and_set_bit(IMX2_WDT_STATUS_STARTED, &imx2_wdt.status)) { + /* at our first start we enable clock and do initialisations */ + clk_enable(imx2_wdt.clk); + + imx2_wdt_setup(); + } else /* delete the timer that pings the watchdog after close */ + del_timer_sync(&imx2_wdt.timer); + + /* Watchdog is enabled - time to reload the timeout value */ + imx2_wdt_ping(); +} + +static void imx2_wdt_stop(void) +{ + /* we don't need a clk_disable, it cannot be disabled once started. + * We use a timer to ping the watchdog while /dev/watchdog is closed */ + imx2_wdt_timer_ping(0); +} + +static void imx2_wdt_set_timeout(int new_timeout) +{ + u16 val = __raw_readw(imx2_wdt.base + IMX2_WDT_WCR); + + /* set the new timeout value in the WSR */ + val &= ~IMX2_WDT_WCR_WT; + val |= WDOG_SEC_TO_COUNT(new_timeout); + __raw_writew(val, imx2_wdt.base + IMX2_WDT_WCR); +} + +static int imx2_wdt_open(struct inode *inode, struct file *file) +{ + if (test_and_set_bit(IMX2_WDT_STATUS_OPEN, &imx2_wdt.status)) + return -EBUSY; + + imx2_wdt_start(); + return nonseekable_open(inode, file); +} + +static int imx2_wdt_close(struct inode *inode, struct file *file) +{ + if (test_bit(IMX2_WDT_EXPECT_CLOSE, &imx2_wdt.status) && !nowayout) + imx2_wdt_stop(); + else { + dev_crit(imx2_wdt_miscdev.parent, + "Unexpected close: Expect reboot!\n"); + imx2_wdt_ping(); + } + + clear_bit(IMX2_WDT_EXPECT_CLOSE, &imx2_wdt.status); + clear_bit(IMX2_WDT_STATUS_OPEN, &imx2_wdt.status); + return 0; +} + +static long imx2_wdt_ioctl(struct file *file, unsigned int cmd, + unsigned long arg) +{ + void __user *argp = (void __user *)arg; + int __user *p = argp; + int new_value; + + switch (cmd) { + case WDIOC_GETSUPPORT: + return copy_to_user(argp, &imx2_wdt_info, + sizeof(struct watchdog_info)) ? -EFAULT : 0; + + case WDIOC_GETSTATUS: + case WDIOC_GETBOOTSTATUS: + return put_user(0, p); + + case WDIOC_KEEPALIVE: + imx2_wdt_ping(); + return 0; + + case WDIOC_SETTIMEOUT: + if (get_user(new_value, p)) + return -EFAULT; + if ((new_value < 1) || (new_value > IMX2_WDT_MAX_TIME)) + return -EINVAL; + imx2_wdt_set_timeout(new_value); + imx2_wdt.timeout = new_value; + imx2_wdt_ping(); + + /* Fallthrough to return current value */ + case WDIOC_GETTIMEOUT: + return put_user(imx2_wdt.timeout, p); + + default: + return -ENOTTY; + } +} + +static ssize_t imx2_wdt_write(struct file *file, const char __user *data, + size_t len, loff_t *ppos) +{ + size_t i; + char c; + + if (len == 0) /* Can we see this even ? */ + return 0; + + clear_bit(IMX2_WDT_EXPECT_CLOSE, &imx2_wdt.status); + /* scan to see whether or not we got the magic character */ + for (i = 0; i != len; i++) { + if (get_user(c, data + i)) + return -EFAULT; + if (c == 'V') + set_bit(IMX2_WDT_EXPECT_CLOSE, &imx2_wdt.status); + } + + imx2_wdt_ping(); + return len; +} + +static const struct file_operations imx2_wdt_fops = { + .owner = THIS_MODULE, + .llseek = no_llseek, + .unlocked_ioctl = imx2_wdt_ioctl, + .open = imx2_wdt_open, + .release = imx2_wdt_close, + .write = imx2_wdt_write, +}; + +static struct miscdevice imx2_wdt_miscdev = { + .minor = WATCHDOG_MINOR, + .name = "watchdog", + .fops = &imx2_wdt_fops, +}; + +static int __init imx2_wdt_probe(struct platform_device *pdev) +{ + int ret; + int res_size; + struct resource *res; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!res) { + dev_err(&pdev->dev, "can't get device resources\n"); + return -ENODEV; + } + + res_size = resource_size(res); + if (!devm_request_mem_region(&pdev->dev, res->start, res_size, + res->name)) { + dev_err(&pdev->dev, "can't allocate %d bytes at %d address\n", + res_size, res->start); + return -ENOMEM; + } + + imx2_wdt.base = devm_ioremap_nocache(&pdev->dev, res->start, res_size); + if (!imx2_wdt.base) { + dev_err(&pdev->dev, "ioremap failed\n"); + return -ENOMEM; + } + + imx2_wdt.clk = clk_get_sys("imx-wdt.0", NULL); + if (IS_ERR(imx2_wdt.clk)) { + dev_err(&pdev->dev, "can't get Watchdog clock\n"); + return PTR_ERR(imx2_wdt.clk); + } + + imx2_wdt.timeout = clamp_t(unsigned, timeout, 1, IMX2_WDT_MAX_TIME); + if (imx2_wdt.timeout != timeout) + dev_warn(&pdev->dev, "Initial timeout out of range! " + "Clamped from %u to %u\n", timeout, imx2_wdt.timeout); + + setup_timer(&imx2_wdt.timer, imx2_wdt_timer_ping, 0); + + imx2_wdt_miscdev.parent = &pdev->dev; + ret = misc_register(&imx2_wdt_miscdev); + if (ret) + goto fail; + + dev_info(&pdev->dev, + "IMX2+ Watchdog Timer enabled. timeout=%ds (nowayout=%d)\n", + imx2_wdt.timeout, nowayout); + return 0; + +fail: + imx2_wdt_miscdev.parent = NULL; + clk_put(imx2_wdt.clk); + return ret; +} + +static int __exit imx2_wdt_remove(struct platform_device *pdev) +{ + misc_deregister(&imx2_wdt_miscdev); + + if (test_bit(IMX2_WDT_STATUS_STARTED, &imx2_wdt.status)) { + del_timer_sync(&imx2_wdt.timer); + + dev_crit(imx2_wdt_miscdev.parent, + "Device removed: Expect reboot!\n"); + } else + clk_put(imx2_wdt.clk); + + imx2_wdt_miscdev.parent = NULL; + return 0; +} + +static void imx2_wdt_shutdown(struct platform_device *pdev) +{ + if (test_bit(IMX2_WDT_STATUS_STARTED, &imx2_wdt.status)) { + /* we are running, we need to delete the timer but will give + * max timeout before reboot will take place */ + del_timer_sync(&imx2_wdt.timer); + imx2_wdt_set_timeout(IMX2_WDT_MAX_TIME); + imx2_wdt_ping(); + + dev_crit(imx2_wdt_miscdev.parent, + "Device shutdown: Expect reboot!\n"); + } +} + +static struct platform_driver imx2_wdt_driver = { + .probe = imx2_wdt_probe, + .remove = __exit_p(imx2_wdt_remove), + .shutdown = imx2_wdt_shutdown, + .driver = { + .name = DRIVER_NAME, + .owner = THIS_MODULE, + }, +}; + +static int __init imx2_wdt_init(void) +{ + return platform_driver_probe(&imx2_wdt_driver, imx2_wdt_probe); +} +module_init(imx2_wdt_init); + +static void __exit imx2_wdt_exit(void) +{ + platform_driver_unregister(&imx2_wdt_driver); +} +module_exit(imx2_wdt_exit); + +MODULE_AUTHOR("Wolfram Sang"); +MODULE_DESCRIPTION("Watchdog driver for IMX2 and later"); +MODULE_LICENSE("GPL v2"); +MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR); +MODULE_ALIAS("platform:" DRIVER_NAME); -- cgit v1.2.3