diff options
Diffstat (limited to 'drivers/watchdog/omap_wdt.c')
| -rw-r--r-- | drivers/watchdog/omap_wdt.c | 445 |
1 files changed, 211 insertions, 234 deletions
diff --git a/drivers/watchdog/omap_wdt.c b/drivers/watchdog/omap_wdt.c index 635ca454f56..3691b157516 100644 --- a/drivers/watchdog/omap_wdt.c +++ b/drivers/watchdog/omap_wdt.c @@ -1,7 +1,7 @@ /* - * linux/drivers/char/watchdog/omap_wdt.c + * omap_wdt.c * - * Watchdog driver for the TI OMAP 16xx & 24xx 32KHz (non-secure) watchdog + * Watchdog driver for the TI OMAP 16xx & 24xx/34xx 32KHz (non-secure) watchdog * * Author: MontaVista Software, Inc. * <gdavis@mvista.com> or <source@mvista.com> @@ -16,7 +16,7 @@ * 20030527: George G. Davis <gdavis@mvista.com> * Initially based on linux-2.4.19-rmk7-pxa1/drivers/char/sa1100_wdt.c * (c) Copyright 2000 Oleg Drokin <green@crimea.edu> - * Based on SoftDog driver by Alan Cox <alan@redhat.com> + * Based on SoftDog driver by Alan Cox <alan@lxorguk.ukuu.org.uk> * * Copyright (c) 2004 Texas Instruments. * 1. Modified to support OMAP1610 32-KHz watchdog timer @@ -26,307 +26,273 @@ * Use the driver model and standard identifiers; handle bigger timeouts. */ +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + #include <linux/module.h> #include <linux/types.h> #include <linux/kernel.h> -#include <linux/fs.h> #include <linux/mm.h> -#include <linux/miscdevice.h> #include <linux/watchdog.h> #include <linux/reboot.h> -#include <linux/init.h> #include <linux/err.h> #include <linux/platform_device.h> #include <linux/moduleparam.h> -#include <linux/clk.h> -#include <linux/bitops.h> - -#include <asm/io.h> -#include <asm/uaccess.h> -#include <asm/hardware.h> - -#include <asm/arch/prcm.h> +#include <linux/io.h> +#include <linux/slab.h> +#include <linux/pm_runtime.h> +#include <linux/platform_data/omap-wd-timer.h> #include "omap_wdt.h" +static bool nowayout = WATCHDOG_NOWAYOUT; +module_param(nowayout, bool, 0); +MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started " + "(default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); + static unsigned timer_margin; module_param(timer_margin, uint, 0); MODULE_PARM_DESC(timer_margin, "initial watchdog timeout (in seconds)"); -static int omap_wdt_users; -static struct clk *armwdt_ck = NULL; -static struct clk *mpu_wdt_ick = NULL; -static struct clk *mpu_wdt_fck = NULL; - -static unsigned int wdt_trgr_pattern = 0x1234; +struct omap_wdt_dev { + void __iomem *base; /* physical */ + struct device *dev; + bool omap_wdt_users; + int wdt_trgr_pattern; + struct mutex lock; /* to avoid races with PM */ +}; -static void omap_wdt_ping(void) +static void omap_wdt_reload(struct omap_wdt_dev *wdev) { + void __iomem *base = wdev->base; + /* wait for posted write to complete */ - while ((omap_readl(OMAP_WATCHDOG_WPS)) & 0x08) + while ((readl_relaxed(base + OMAP_WATCHDOG_WPS)) & 0x08) cpu_relax(); - wdt_trgr_pattern = ~wdt_trgr_pattern; - omap_writel(wdt_trgr_pattern, (OMAP_WATCHDOG_TGR)); + + wdev->wdt_trgr_pattern = ~wdev->wdt_trgr_pattern; + writel_relaxed(wdev->wdt_trgr_pattern, (base + OMAP_WATCHDOG_TGR)); + /* wait for posted write to complete */ - while ((omap_readl(OMAP_WATCHDOG_WPS)) & 0x08) + while ((readl_relaxed(base + OMAP_WATCHDOG_WPS)) & 0x08) cpu_relax(); /* reloaded WCRR from WLDR */ } -static void omap_wdt_enable(void) +static void omap_wdt_enable(struct omap_wdt_dev *wdev) { + void __iomem *base = wdev->base; + /* Sequence to enable the watchdog */ - omap_writel(0xBBBB, OMAP_WATCHDOG_SPR); - while ((omap_readl(OMAP_WATCHDOG_WPS)) & 0x10) + writel_relaxed(0xBBBB, base + OMAP_WATCHDOG_SPR); + while ((readl_relaxed(base + OMAP_WATCHDOG_WPS)) & 0x10) cpu_relax(); - omap_writel(0x4444, OMAP_WATCHDOG_SPR); - while ((omap_readl(OMAP_WATCHDOG_WPS)) & 0x10) + + writel_relaxed(0x4444, base + OMAP_WATCHDOG_SPR); + while ((readl_relaxed(base + OMAP_WATCHDOG_WPS)) & 0x10) cpu_relax(); } -static void omap_wdt_disable(void) +static void omap_wdt_disable(struct omap_wdt_dev *wdev) { + void __iomem *base = wdev->base; + /* sequence required to disable watchdog */ - omap_writel(0xAAAA, OMAP_WATCHDOG_SPR); /* TIMER_MODE */ - while (omap_readl(OMAP_WATCHDOG_WPS) & 0x10) + writel_relaxed(0xAAAA, base + OMAP_WATCHDOG_SPR); /* TIMER_MODE */ + while (readl_relaxed(base + OMAP_WATCHDOG_WPS) & 0x10) cpu_relax(); - omap_writel(0x5555, OMAP_WATCHDOG_SPR); /* TIMER_MODE */ - while (omap_readl(OMAP_WATCHDOG_WPS) & 0x10) - cpu_relax(); -} -static void omap_wdt_adjust_timeout(unsigned new_timeout) -{ - if (new_timeout < TIMER_MARGIN_MIN) - new_timeout = TIMER_MARGIN_DEFAULT; - if (new_timeout > TIMER_MARGIN_MAX) - new_timeout = TIMER_MARGIN_MAX; - timer_margin = new_timeout; + writel_relaxed(0x5555, base + OMAP_WATCHDOG_SPR); /* TIMER_MODE */ + while (readl_relaxed(base + OMAP_WATCHDOG_WPS) & 0x10) + cpu_relax(); } -static void omap_wdt_set_timeout(void) +static void omap_wdt_set_timer(struct omap_wdt_dev *wdev, + unsigned int timeout) { - u32 pre_margin = GET_WLDR_VAL(timer_margin); + u32 pre_margin = GET_WLDR_VAL(timeout); + void __iomem *base = wdev->base; /* just count up at 32 KHz */ - while (omap_readl(OMAP_WATCHDOG_WPS) & 0x04) + while (readl_relaxed(base + OMAP_WATCHDOG_WPS) & 0x04) cpu_relax(); - omap_writel(pre_margin, OMAP_WATCHDOG_LDR); - while (omap_readl(OMAP_WATCHDOG_WPS) & 0x04) + + writel_relaxed(pre_margin, base + OMAP_WATCHDOG_LDR); + while (readl_relaxed(base + OMAP_WATCHDOG_WPS) & 0x04) cpu_relax(); } -/* - * Allow only one task to hold it open - */ - -static int omap_wdt_open(struct inode *inode, struct file *file) +static int omap_wdt_start(struct watchdog_device *wdog) { - if (test_and_set_bit(1, (unsigned long *)&omap_wdt_users)) - return -EBUSY; + struct omap_wdt_dev *wdev = watchdog_get_drvdata(wdog); + void __iomem *base = wdev->base; - if (cpu_is_omap16xx()) - clk_enable(armwdt_ck); /* Enable the clock */ + mutex_lock(&wdev->lock); - if (cpu_is_omap24xx()) { - clk_enable(mpu_wdt_ick); /* Enable the interface clock */ - clk_enable(mpu_wdt_fck); /* Enable the functional clock */ - } + wdev->omap_wdt_users = true; + + pm_runtime_get_sync(wdev->dev); /* initialize prescaler */ - while (omap_readl(OMAP_WATCHDOG_WPS) & 0x01) + while (readl_relaxed(base + OMAP_WATCHDOG_WPS) & 0x01) cpu_relax(); - omap_writel((1 << 5) | (PTV << 2), OMAP_WATCHDOG_CNTRL); - while (omap_readl(OMAP_WATCHDOG_WPS) & 0x01) + + writel_relaxed((1 << 5) | (PTV << 2), base + OMAP_WATCHDOG_CNTRL); + while (readl_relaxed(base + OMAP_WATCHDOG_WPS) & 0x01) cpu_relax(); - omap_wdt_set_timeout(); - omap_wdt_enable(); - return nonseekable_open(inode, file); + omap_wdt_set_timer(wdev, wdog->timeout); + omap_wdt_reload(wdev); /* trigger loading of new timeout value */ + omap_wdt_enable(wdev); + + mutex_unlock(&wdev->lock); + + return 0; } -static int omap_wdt_release(struct inode *inode, struct file *file) +static int omap_wdt_stop(struct watchdog_device *wdog) { - /* - * Shut off the timer unless NOWAYOUT is defined. - */ -#ifndef CONFIG_WATCHDOG_NOWAYOUT - omap_wdt_disable(); - - if (cpu_is_omap16xx()) { - clk_disable(armwdt_ck); /* Disable the clock */ - clk_put(armwdt_ck); - armwdt_ck = NULL; - } + struct omap_wdt_dev *wdev = watchdog_get_drvdata(wdog); - if (cpu_is_omap24xx()) { - clk_disable(mpu_wdt_ick); /* Disable the clock */ - clk_disable(mpu_wdt_fck); /* Disable the clock */ - clk_put(mpu_wdt_ick); - clk_put(mpu_wdt_fck); - mpu_wdt_ick = NULL; - mpu_wdt_fck = NULL; - } -#else - printk(KERN_CRIT "omap_wdt: Unexpected close, not stopping!\n"); -#endif - omap_wdt_users = 0; + mutex_lock(&wdev->lock); + omap_wdt_disable(wdev); + pm_runtime_put_sync(wdev->dev); + wdev->omap_wdt_users = false; + mutex_unlock(&wdev->lock); return 0; } -static ssize_t -omap_wdt_write(struct file *file, const char __user *data, - size_t len, loff_t *ppos) +static int omap_wdt_ping(struct watchdog_device *wdog) { - /* Refresh LOAD_TIME. */ - if (len) - omap_wdt_ping(); - return len; + struct omap_wdt_dev *wdev = watchdog_get_drvdata(wdog); + + mutex_lock(&wdev->lock); + omap_wdt_reload(wdev); + mutex_unlock(&wdev->lock); + + return 0; } -static int -omap_wdt_ioctl(struct inode *inode, struct file *file, - unsigned int cmd, unsigned long arg) +static int omap_wdt_set_timeout(struct watchdog_device *wdog, + unsigned int timeout) { - int new_margin; - static struct watchdog_info ident = { - .identity = "OMAP Watchdog", - .options = WDIOF_SETTIMEOUT, - .firmware_version = 0, - }; - - switch (cmd) { - default: - return -ENOTTY; - case WDIOC_GETSUPPORT: - return copy_to_user((struct watchdog_info __user *)arg, &ident, - sizeof(ident)); - case WDIOC_GETSTATUS: - return put_user(0, (int __user *)arg); - case WDIOC_GETBOOTSTATUS: - if (cpu_is_omap16xx()) - return put_user(omap_readw(ARM_SYSST), - (int __user *)arg); - if (cpu_is_omap24xx()) - return put_user(omap_prcm_get_reset_sources(), - (int __user *)arg); - case WDIOC_KEEPALIVE: - omap_wdt_ping(); - return 0; - case WDIOC_SETTIMEOUT: - if (get_user(new_margin, (int __user *)arg)) - return -EFAULT; - omap_wdt_adjust_timeout(new_margin); - - omap_wdt_disable(); - omap_wdt_set_timeout(); - omap_wdt_enable(); - - omap_wdt_ping(); - /* Fall */ - case WDIOC_GETTIMEOUT: - return put_user(timer_margin, (int __user *)arg); - } + struct omap_wdt_dev *wdev = watchdog_get_drvdata(wdog); + + mutex_lock(&wdev->lock); + omap_wdt_disable(wdev); + omap_wdt_set_timer(wdev, timeout); + omap_wdt_enable(wdev); + omap_wdt_reload(wdev); + wdog->timeout = timeout; + mutex_unlock(&wdev->lock); + + return 0; } -static const struct file_operations omap_wdt_fops = { - .owner = THIS_MODULE, - .write = omap_wdt_write, - .ioctl = omap_wdt_ioctl, - .open = omap_wdt_open, - .release = omap_wdt_release, +static const struct watchdog_info omap_wdt_info = { + .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING, + .identity = "OMAP Watchdog", }; -static struct miscdevice omap_wdt_miscdev = { - .minor = WATCHDOG_MINOR, - .name = "watchdog", - .fops = &omap_wdt_fops +static const struct watchdog_ops omap_wdt_ops = { + .owner = THIS_MODULE, + .start = omap_wdt_start, + .stop = omap_wdt_stop, + .ping = omap_wdt_ping, + .set_timeout = omap_wdt_set_timeout, }; -static int __init omap_wdt_probe(struct platform_device *pdev) +static int omap_wdt_probe(struct platform_device *pdev) { - struct resource *res, *mem; + struct omap_wd_timer_platform_data *pdata = dev_get_platdata(&pdev->dev); + struct watchdog_device *omap_wdt; + struct resource *res; + struct omap_wdt_dev *wdev; + u32 rs; int ret; - /* reserve static register mappings */ - res = platform_get_resource(pdev, IORESOURCE_MEM, 0); - if (!res) - return -ENOENT; - - mem = request_mem_region(res->start, res->end - res->start + 1, - pdev->name); - if (mem == NULL) - return -EBUSY; - - platform_set_drvdata(pdev, mem); + omap_wdt = devm_kzalloc(&pdev->dev, sizeof(*omap_wdt), GFP_KERNEL); + if (!omap_wdt) + return -ENOMEM; - omap_wdt_users = 0; + wdev = devm_kzalloc(&pdev->dev, sizeof(*wdev), GFP_KERNEL); + if (!wdev) + return -ENOMEM; - if (cpu_is_omap16xx()) { - armwdt_ck = clk_get(&pdev->dev, "armwdt_ck"); - if (IS_ERR(armwdt_ck)) { - ret = PTR_ERR(armwdt_ck); - armwdt_ck = NULL; - goto fail; - } - } + wdev->omap_wdt_users = false; + wdev->dev = &pdev->dev; + wdev->wdt_trgr_pattern = 0x1234; + mutex_init(&wdev->lock); - if (cpu_is_omap24xx()) { - mpu_wdt_ick = clk_get(&pdev->dev, "mpu_wdt_ick"); - if (IS_ERR(mpu_wdt_ick)) { - ret = PTR_ERR(mpu_wdt_ick); - mpu_wdt_ick = NULL; - goto fail; - } - mpu_wdt_fck = clk_get(&pdev->dev, "mpu_wdt_fck"); - if (IS_ERR(mpu_wdt_fck)) { - ret = PTR_ERR(mpu_wdt_fck); - mpu_wdt_fck = NULL; - goto fail; - } + /* reserve static register mappings */ + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + wdev->base = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(wdev->base)) + return PTR_ERR(wdev->base); + + omap_wdt->info = &omap_wdt_info; + omap_wdt->ops = &omap_wdt_ops; + omap_wdt->min_timeout = TIMER_MARGIN_MIN; + omap_wdt->max_timeout = TIMER_MARGIN_MAX; + + if (timer_margin >= TIMER_MARGIN_MIN && + timer_margin <= TIMER_MARGIN_MAX) + omap_wdt->timeout = timer_margin; + else + omap_wdt->timeout = TIMER_MARGIN_DEFAULT; + + watchdog_set_drvdata(omap_wdt, wdev); + watchdog_set_nowayout(omap_wdt, nowayout); + + platform_set_drvdata(pdev, omap_wdt); + + pm_runtime_enable(wdev->dev); + pm_runtime_get_sync(wdev->dev); + + if (pdata && pdata->read_reset_sources) + rs = pdata->read_reset_sources(); + else + rs = 0; + omap_wdt->bootstatus = (rs & (1 << OMAP_MPU_WD_RST_SRC_ID_SHIFT)) ? + WDIOF_CARDRESET : 0; + + omap_wdt_disable(wdev); + + ret = watchdog_register_device(omap_wdt); + if (ret) { + pm_runtime_disable(wdev->dev); + return ret; } - omap_wdt_disable(); - omap_wdt_adjust_timeout(timer_margin); - - omap_wdt_miscdev.parent = &pdev->dev; - ret = misc_register(&omap_wdt_miscdev); - if (ret) - goto fail; + pr_info("OMAP Watchdog Timer Rev 0x%02x: initial timeout %d sec\n", + readl_relaxed(wdev->base + OMAP_WATCHDOG_REV) & 0xFF, + omap_wdt->timeout); - pr_info("OMAP Watchdog Timer: initial timeout %d sec\n", timer_margin); + pm_runtime_put_sync(wdev->dev); - /* autogate OCP interface clock */ - omap_writel(0x01, OMAP_WATCHDOG_SYS_CONFIG); return 0; - -fail: - if (armwdt_ck) - clk_put(armwdt_ck); - if (mpu_wdt_ick) - clk_put(mpu_wdt_ick); - if (mpu_wdt_fck) - clk_put(mpu_wdt_fck); - release_resource(mem); - return ret; } static void omap_wdt_shutdown(struct platform_device *pdev) { - omap_wdt_disable(); + struct watchdog_device *wdog = platform_get_drvdata(pdev); + struct omap_wdt_dev *wdev = watchdog_get_drvdata(wdog); + + mutex_lock(&wdev->lock); + if (wdev->omap_wdt_users) { + omap_wdt_disable(wdev); + pm_runtime_put_sync(wdev->dev); + } + mutex_unlock(&wdev->lock); } static int omap_wdt_remove(struct platform_device *pdev) { - struct resource *mem = platform_get_drvdata(pdev); - misc_deregister(&omap_wdt_miscdev); - release_resource(mem); - if (armwdt_ck) - clk_put(armwdt_ck); - if (mpu_wdt_ick) - clk_put(mpu_wdt_ick); - if (mpu_wdt_fck) - clk_put(mpu_wdt_fck); + struct watchdog_device *wdog = platform_get_drvdata(pdev); + struct omap_wdt_dev *wdev = watchdog_get_drvdata(wdog); + + pm_runtime_disable(wdev->dev); + watchdog_unregister_device(wdog); + return 0; } @@ -340,17 +306,32 @@ static int omap_wdt_remove(struct platform_device *pdev) static int omap_wdt_suspend(struct platform_device *pdev, pm_message_t state) { - if (omap_wdt_users) - omap_wdt_disable(); + struct watchdog_device *wdog = platform_get_drvdata(pdev); + struct omap_wdt_dev *wdev = watchdog_get_drvdata(wdog); + + mutex_lock(&wdev->lock); + if (wdev->omap_wdt_users) { + omap_wdt_disable(wdev); + pm_runtime_put_sync(wdev->dev); + } + mutex_unlock(&wdev->lock); + return 0; } static int omap_wdt_resume(struct platform_device *pdev) { - if (omap_wdt_users) { - omap_wdt_enable(); - omap_wdt_ping(); + struct watchdog_device *wdog = platform_get_drvdata(pdev); + struct omap_wdt_dev *wdev = watchdog_get_drvdata(wdog); + + mutex_lock(&wdev->lock); + if (wdev->omap_wdt_users) { + pm_runtime_get_sync(wdev->dev); + omap_wdt_enable(wdev); + omap_wdt_reload(wdev); } + mutex_unlock(&wdev->lock); + return 0; } @@ -359,6 +340,12 @@ static int omap_wdt_resume(struct platform_device *pdev) #define omap_wdt_resume NULL #endif +static const struct of_device_id omap_wdt_of_match[] = { + { .compatible = "ti,omap3-wdt", }, + {}, +}; +MODULE_DEVICE_TABLE(of, omap_wdt_of_match); + static struct platform_driver omap_wdt_driver = { .probe = omap_wdt_probe, .remove = omap_wdt_remove, @@ -368,22 +355,12 @@ static struct platform_driver omap_wdt_driver = { .driver = { .owner = THIS_MODULE, .name = "omap_wdt", + .of_match_table = omap_wdt_of_match, }, }; -static int __init omap_wdt_init(void) -{ - return platform_driver_register(&omap_wdt_driver); -} - -static void __exit omap_wdt_exit(void) -{ - platform_driver_unregister(&omap_wdt_driver); -} - -module_init(omap_wdt_init); -module_exit(omap_wdt_exit); +module_platform_driver(omap_wdt_driver); MODULE_AUTHOR("George G. Davis"); MODULE_LICENSE("GPL"); -MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR); +MODULE_ALIAS("platform:omap_wdt"); |
