add hardware watchdog driver
authorGabor Juhos <juhosg@openwrt.org>
Tue, 30 Sep 2008 08:05:18 +0000 (08:05 +0000)
committerGabor Juhos <juhosg@openwrt.org>
Tue, 30 Sep 2008 08:05:18 +0000 (08:05 +0000)
SVN-Revision: 12810

target/linux/ar71xx/config-2.6.26
target/linux/ar71xx/files/arch/mips/ar71xx/ar71xx.c
target/linux/ar71xx/files/arch/mips/ar71xx/platform.c
target/linux/ar71xx/files/drivers/watchdog/ar71xx_wdt.c [new file with mode: 0644]
target/linux/ar71xx/files/include/asm-mips/mach-ar71xx/ar71xx.h

index ea56b8d101ef952a9292405e9d800531f3070520..40f0f4fb1ea74710577df9486e88d65e8931ddb5 100644 (file)
@@ -7,6 +7,7 @@ CONFIG_AG71XX=y
 CONFIG_AR71XX_MACH_GENERIC=y
 CONFIG_AR71XX_MACH_RB_4XX=y
 CONFIG_AR71XX_MACH_WP543=y
+CONFIG_AR71XX_WDT=y
 # CONFIG_ARCH_HAS_ILOG2_U32 is not set
 # CONFIG_ARCH_HAS_ILOG2_U64 is not set
 CONFIG_ARCH_POPULATES_NODE_MAP=y
index c88225c5f7239d6cf3f025ed73faf59d6bfd07d6..52fcf5084d78f22bd5d2ed73f25fc6ed605225a7 100644 (file)
 #include <asm/mach-ar71xx/ar71xx.h>
 
 void __iomem *ar71xx_ddr_base;
+EXPORT_SYMBOL_GPL(ar71xx_ddr_base);
+
 void __iomem *ar71xx_pll_base;
+EXPORT_SYMBOL_GPL(ar71xx_pll_base);
+
 void __iomem *ar71xx_reset_base;
+EXPORT_SYMBOL_GPL(ar71xx_reset_base);
+
 void __iomem *ar71xx_gpio_base;
+EXPORT_SYMBOL_GPL(ar71xx_gpio_base);
+
 void __iomem *ar71xx_usb_ctrl_base;
+EXPORT_SYMBOL_GPL(ar71xx_usb_ctrl_base);
 
 void ar71xx_device_stop(u32 mask)
 {
index ce98084d633ba0b70e949a0c01e701dcb2929807..b131ec1e27f7b2ebc45575dc53b4e552f92c3bf3 100644 (file)
@@ -414,6 +414,11 @@ err_free_buttons:
        kfree(p);
 }
 
+void __init ar71xx_add_device_wdt(void)
+{
+       platform_device_register_simple("ar71xx-wdt", -1, NULL, 0);
+}
+
 void __init ar71xx_set_mac_base(unsigned char *mac)
 {
        memcpy(ar71xx_mac_base, mac, ETH_ALEN);
@@ -439,6 +444,7 @@ static int __init ar71xx_machine_setup(void)
        ar71xx_gpio_init();
 
        ar71xx_add_device_uart();
+       ar71xx_add_device_wdt();
 
        mips_machine_setup();
        return 0;
diff --git a/target/linux/ar71xx/files/drivers/watchdog/ar71xx_wdt.c b/target/linux/ar71xx/files/drivers/watchdog/ar71xx_wdt.c
new file mode 100644 (file)
index 0000000..9f14ff7
--- /dev/null
@@ -0,0 +1,270 @@
+/*
+ * Driver for the Atheros AR71xx SoC's built-in hardware watchdog timer.
+ *
+ * Copyright (C) 2008 Gabor Juhos <juhosg@openwrt.org>
+ * Copyright (C) 2008 Imre Kaloz <kaloz@openwrt.org>
+ *
+ * This driver was based on: drivers/watchdog/ixp4xx_wdt.c
+ *     Author: Deepak Saxena <dsaxena@plexity.net>
+ *     Copyright 2004 (c) MontaVista, Software, Inc.
+ *
+ * which again was based on sa1100 driver,
+ *     Copyright (C) 2000 Oleg Drokin <green@crimea.edu>
+ *
+ * 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.
+ *
+ */
+
+#include <linux/bitops.h>
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/miscdevice.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/platform_device.h>
+#include <linux/types.h>
+#include <linux/watchdog.h>
+
+#include <asm/mach-ar71xx/ar71xx.h>
+
+#define DRV_NAME       "ar71xx-wdt"
+#define DRV_DESC       "Atheros AR71xx hardware watchdog driver"
+#define DRV_VERSION    "0.1.0"
+
+#define WDT_TIMEOUT    15      /* seconds */
+
+static int nowayout = WATCHDOG_NOWAYOUT;
+
+#ifdef CONFIG_WATCHDOG_NOWAYOUT
+module_param(nowayout, int, 0);
+MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started "
+                          "(default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
+#endif
+
+static unsigned long wdt_flags;
+
+#define WDT_FLAGS_BUSY         0
+#define WDT_FLAGS_EXPECT_CLOSE 1
+
+static int wdt_timeout = WDT_TIMEOUT;
+static int boot_status;
+static int max_timeout;
+
+static void inline ar71xx_wdt_keepalive(void)
+{
+       ar71xx_reset_wr(RESET_REG_WDOG, ar71xx_ahb_freq * wdt_timeout);
+}
+
+static void inline ar71xx_wdt_enable(void)
+{
+       printk(KERN_DEBUG DRV_NAME ": enabling watchdog timer\n");
+       ar71xx_wdt_keepalive();
+       ar71xx_reset_wr(RESET_REG_WDOG_CTRL, WDOG_CTRL_ACTION_FCR);
+}
+
+static void inline ar71xx_wdt_disable(void)
+{
+       printk(KERN_DEBUG DRV_NAME ": disabling watchdog timer\n");
+       ar71xx_reset_wr(RESET_REG_WDOG_CTRL, WDOG_CTRL_ACTION_NONE);
+}
+
+static int ar71xx_wdt_set_timeout(int val)
+{
+       if (val < 1 || val > max_timeout)
+               return -EINVAL;
+
+       wdt_timeout = val;
+       ar71xx_wdt_keepalive();
+
+       printk(KERN_DEBUG DRV_NAME ": timeout=%d secs\n", wdt_timeout);
+
+       return 0;
+}
+
+static int ar71xx_wdt_open(struct inode *inode, struct file *file)
+{
+       if (test_and_set_bit(WDT_FLAGS_BUSY, &wdt_flags))
+               return -EBUSY;
+
+       clear_bit(WDT_FLAGS_EXPECT_CLOSE, &wdt_flags);
+
+       ar71xx_wdt_enable();
+
+       return nonseekable_open(inode, file);
+}
+
+static int ar71xx_wdt_release(struct inode *inode, struct file *file)
+{
+       if (test_bit(WDT_FLAGS_EXPECT_CLOSE, &wdt_flags)) {
+               ar71xx_wdt_disable();
+       } else {
+               printk(KERN_CRIT DRV_NAME ": device closed unexpectedly, "
+                                       "watchdog timer will not stop!\n");
+       }
+
+       clear_bit(WDT_FLAGS_BUSY, &wdt_flags);
+       clear_bit(WDT_FLAGS_EXPECT_CLOSE, &wdt_flags);
+
+       return 0;
+}
+
+static ssize_t ar71xx_wdt_write(struct file *file, const char *data,
+                               size_t len, loff_t *ppos)
+{
+        if (len) {
+               if (!nowayout) {
+                       size_t i;
+
+                       clear_bit(WDT_FLAGS_EXPECT_CLOSE, &wdt_flags);
+
+                       for (i = 0; i != len; i++) {
+                               char c;
+
+                               if (get_user(c, data + i))
+                                       return -EFAULT;
+
+                               if (c == 'V')
+                                       set_bit(WDT_FLAGS_EXPECT_CLOSE,
+                                               &wdt_flags);
+                       }
+               }
+
+               ar71xx_wdt_keepalive();
+       }
+
+       return len;
+}
+
+static struct watchdog_info ar71xx_wdt_info = {
+       .options                = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING |
+                                 WDIOF_MAGICCLOSE | WDIOF_CARDRESET,
+       .firmware_version       = 0,
+       .identity               = "AR71XX watchdog",
+};
+
+static int ar71xx_wdt_ioctl(struct inode *inode, struct file *file,
+                           unsigned int cmd, unsigned long arg)
+{
+       int t;
+       int ret;
+
+       switch (cmd) {
+       case WDIOC_GETSUPPORT:
+               ret = copy_to_user((struct watchdog_info *)arg,
+                                  &ar71xx_wdt_info,
+                                  sizeof(&ar71xx_wdt_info)) ? -EFAULT : 0;
+               break;
+
+       case WDIOC_GETSTATUS:
+               ret = put_user(0, (int *)arg) ? -EFAULT : 0;
+               break;
+
+       case WDIOC_GETBOOTSTATUS:
+               ret = put_user(boot_status, (int *)arg) ? -EFAULT : 0;
+               break;
+
+       case WDIOC_KEEPALIVE:
+               ar71xx_wdt_keepalive();
+               ret = 0;
+               break;
+
+       case WDIOC_SETTIMEOUT:
+               ret = get_user(t, (int *)arg) ? -EFAULT : 0;
+               if (ret)
+                       break;
+
+               ret = ar71xx_wdt_set_timeout(t);
+               if (ret)
+                       break;
+
+               /* fallthrough */
+       case WDIOC_GETTIMEOUT:
+               ret = put_user(wdt_timeout, (int *)arg) ? -EFAULT : 0;
+               break;
+
+       default:
+               ret = -ENOTTY;
+               break;
+       }
+
+       return ret;
+}
+
+static const struct file_operations ar71xx_wdt_fops = {
+       .owner          = THIS_MODULE,
+       .write          = ar71xx_wdt_write,
+       .ioctl          = ar71xx_wdt_ioctl,
+       .open           = ar71xx_wdt_open,
+       .release        = ar71xx_wdt_release,
+};
+
+static struct miscdevice ar71xx_wdt_miscdev = {
+       .minor = WATCHDOG_MINOR,
+       .name = "watchdog",
+       .fops = &ar71xx_wdt_fops,
+};
+
+static int __devinit ar71xx_wdt_probe(struct platform_device *pdev)
+{
+       int ret;
+
+       max_timeout = (0xfffffffful / ar71xx_ahb_freq);
+       wdt_timeout = (max_timeout < WDT_TIMEOUT) ? max_timeout : WDT_TIMEOUT;
+
+       boot_status =
+               (ar71xx_reset_rr(RESET_REG_WDOG_CTRL) & WDOG_CTRL_LAST_RESET) ?
+               WDIOF_CARDRESET : 0;
+
+       ret = misc_register(&ar71xx_wdt_miscdev);
+       if (ret)
+               goto err_out;
+
+       printk(KERN_INFO DRV_DESC " version " DRV_VERSION "\n");
+
+       printk(KERN_DEBUG DRV_NAME ": timeout=%d secs (max=%d)\n",
+                                       wdt_timeout, max_timeout);
+
+       return 0;
+
+err_out:
+       return ret;
+}
+
+static int __devexit ar71xx_wdt_remove(struct platform_device *pdev)
+{
+       misc_deregister(&ar71xx_wdt_miscdev);
+       return 0;
+}
+
+static struct platform_driver ar71xx_wdt_driver = {
+       .probe          = ar71xx_wdt_probe,
+       .remove         = __devexit_p(ar71xx_wdt_remove),
+       .driver         = {
+               .name   = DRV_NAME,
+               .owner  = THIS_MODULE,
+       },
+};
+
+static int __init ar71xx_wdt_init(void)
+{
+       return platform_driver_register(&ar71xx_wdt_driver);
+}
+module_init(ar71xx_wdt_init);
+
+static void __exit ar71xx_wdt_exit(void)
+{
+       platform_driver_unregister(&ar71xx_wdt_driver);
+}
+module_exit(ar71xx_wdt_exit);
+
+MODULE_DESCRIPTION(DRV_DESC);
+MODULE_VERSION(DRV_VERSION);
+MODULE_AUTHOR("Gabor Juhos <juhosg@openwrt.org");
+MODULE_AUTHOR("Imre Kaloz <kaloz@openwrt.org");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:" DRV_NAME);
+MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
index 92e662e2ba23521eaed2ab968d50d46f41917a27..729ec9452b99455b3512aadf26650a12f9f45e87 100644 (file)
@@ -275,6 +275,13 @@ extern void ar71xx_ddr_flush(u32 reg);
 #define RESET_REG_PERFC1               0x34
 #define RESET_REG_REV_ID               0x90
 
+#define WDOG_CTRL_LAST_RESET           BIT(31)
+#define WDOG_CTRL_ACTION_MASK          3
+#define WDOG_CTRL_ACTION_NONE          0       /* no action */
+#define WDOG_CTRL_ACTION_GPI           1       /* general purpose interrupt */
+#define WDOG_CTRL_ACTION_NMI           2       /* NMI */
+#define WDOG_CTRL_ACTION_FCR           3       /* full chip reset */
+
 #define MISC_INT_DMA                   BIT(7)
 #define MISC_INT_OHCI                  BIT(6)
 #define MISC_INT_PERFC                 BIT(5)