|
|
@@ -0,0 +1,191 @@
|
|
|
+/*
|
|
|
+ * drivers/char/watchdog/booke_wdt.c
|
|
|
+ *
|
|
|
+ * Watchdog timer for PowerPC Book-E systems
|
|
|
+ *
|
|
|
+ * Author: Matthew McClintock
|
|
|
+ * Maintainer: Kumar Gala <kumar.gala@freescale.com>
|
|
|
+ *
|
|
|
+ * Copyright 2005 Freescale Semiconductor Inc.
|
|
|
+ *
|
|
|
+ * This program is free software; you can redistribute it and/or modify it
|
|
|
+ * under the terms of the GNU General Public License as published by the
|
|
|
+ * Free Software Foundation; either version 2 of the License, or (at your
|
|
|
+ * option) any later version.
|
|
|
+ */
|
|
|
+
|
|
|
+#include <linux/config.h>
|
|
|
+#include <linux/module.h>
|
|
|
+#include <linux/fs.h>
|
|
|
+#include <linux/miscdevice.h>
|
|
|
+#include <linux/notifier.h>
|
|
|
+#include <linux/watchdog.h>
|
|
|
+
|
|
|
+#include <asm/reg_booke.h>
|
|
|
+#include <asm/uaccess.h>
|
|
|
+
|
|
|
+/* If the kernel parameter wdt_enable=1, the watchdog will be enabled at boot.
|
|
|
+ * Also, the wdt_period sets the watchdog timer period timeout.
|
|
|
+ * For E500 cpus the wdt_period sets which bit changing from 0->1 will
|
|
|
+ * trigger a watchog timeout. This watchdog timeout will occur 3 times, the
|
|
|
+ * first time nothing will happen, the second time a watchdog exception will
|
|
|
+ * occur, and the final time the board will reset.
|
|
|
+ */
|
|
|
+
|
|
|
+#ifdef CONFIG_FSL_BOOKE
|
|
|
+#define WDT_PERIOD_DEFAULT 63 /* Ex. wdt_period=28 bus=333Mhz , reset=~40sec */
|
|
|
+#else
|
|
|
+#define WDT_PERIOD_DEFAULT 4 /* Refer to the PPC40x and PPC4xx manuals */
|
|
|
+#endif /* for timing information */
|
|
|
+
|
|
|
+u32 wdt_enable = 0;
|
|
|
+u32 wdt_period = WDT_PERIOD_DEFAULT;
|
|
|
+
|
|
|
+#ifdef CONFIG_FSL_BOOKE
|
|
|
+#define WDTP(x) ((((63-x)&0x3)<<30)|(((63-x)&0x3c)<<15))
|
|
|
+#else
|
|
|
+#define WDTP(x) (TCR_WP(x))
|
|
|
+#endif
|
|
|
+
|
|
|
+/*
|
|
|
+ * booke_wdt_enable:
|
|
|
+ */
|
|
|
+static __inline__ void booke_wdt_enable(void)
|
|
|
+{
|
|
|
+ u32 val;
|
|
|
+
|
|
|
+ val = mfspr(SPRN_TCR);
|
|
|
+ val |= (TCR_WIE|TCR_WRC(WRC_CHIP)|WDTP(wdt_period));
|
|
|
+
|
|
|
+ mtspr(SPRN_TCR, val);
|
|
|
+}
|
|
|
+
|
|
|
+/*
|
|
|
+ * booke_wdt_ping:
|
|
|
+ */
|
|
|
+static __inline__ void booke_wdt_ping(void)
|
|
|
+{
|
|
|
+ mtspr(SPRN_TSR, TSR_ENW|TSR_WIS);
|
|
|
+}
|
|
|
+
|
|
|
+/*
|
|
|
+ * booke_wdt_write:
|
|
|
+ */
|
|
|
+static ssize_t booke_wdt_write (struct file *file, const char *buf,
|
|
|
+ size_t count, loff_t *ppos)
|
|
|
+{
|
|
|
+ booke_wdt_ping();
|
|
|
+ return count;
|
|
|
+}
|
|
|
+
|
|
|
+static struct watchdog_info ident = {
|
|
|
+ .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING,
|
|
|
+ .firmware_version = 0,
|
|
|
+ .identity = "PowerPC Book-E Watchdog",
|
|
|
+};
|
|
|
+
|
|
|
+/*
|
|
|
+ * booke_wdt_ioctl:
|
|
|
+ */
|
|
|
+static int booke_wdt_ioctl (struct inode *inode, struct file *file,
|
|
|
+ unsigned int cmd, unsigned long arg)
|
|
|
+{
|
|
|
+ u32 tmp = 0;
|
|
|
+
|
|
|
+ switch (cmd) {
|
|
|
+ case WDIOC_GETSUPPORT:
|
|
|
+ if (copy_to_user ((struct watchdog_info *) arg, &ident,
|
|
|
+ sizeof(struct watchdog_info)))
|
|
|
+ return -EFAULT;
|
|
|
+ case WDIOC_GETSTATUS:
|
|
|
+ return put_user(ident.options, (u32 *) arg);
|
|
|
+ case WDIOC_GETBOOTSTATUS:
|
|
|
+ /* XXX: something is clearing TSR */
|
|
|
+ tmp = mfspr(SPRN_TSR) & TSR_WRS(3);
|
|
|
+ /* returns 1 if last reset was caused by the WDT */
|
|
|
+ return (tmp ? 1 : 0);
|
|
|
+ case WDIOC_KEEPALIVE:
|
|
|
+ booke_wdt_ping();
|
|
|
+ return 0;
|
|
|
+ case WDIOC_SETTIMEOUT:
|
|
|
+ if (get_user(wdt_period, (u32 *) arg))
|
|
|
+ return -EFAULT;
|
|
|
+ mtspr(SPRN_TCR, (mfspr(SPRN_TCR)&~WDTP(0))|WDTP(wdt_period));
|
|
|
+ return 0;
|
|
|
+ case WDIOC_GETTIMEOUT:
|
|
|
+ return put_user(wdt_period, (u32 *) arg);
|
|
|
+ case WDIOC_SETOPTIONS:
|
|
|
+ if (get_user(tmp, (u32 *) arg))
|
|
|
+ return -EINVAL;
|
|
|
+ if (tmp == WDIOS_ENABLECARD) {
|
|
|
+ booke_wdt_ping();
|
|
|
+ break;
|
|
|
+ } else
|
|
|
+ return -EINVAL;
|
|
|
+ return 0;
|
|
|
+ default:
|
|
|
+ return -ENOIOCTLCMD;
|
|
|
+ }
|
|
|
+
|
|
|
+ return 0;
|
|
|
+}
|
|
|
+/*
|
|
|
+ * booke_wdt_open:
|
|
|
+ */
|
|
|
+static int booke_wdt_open (struct inode *inode, struct file *file)
|
|
|
+{
|
|
|
+ if (wdt_enable == 0) {
|
|
|
+ wdt_enable = 1;
|
|
|
+ booke_wdt_enable();
|
|
|
+ printk (KERN_INFO "PowerPC Book-E Watchdog Timer Enabled (wdt_period=%d)\n",
|
|
|
+ wdt_period);
|
|
|
+ }
|
|
|
+
|
|
|
+ return 0;
|
|
|
+}
|
|
|
+
|
|
|
+static struct file_operations booke_wdt_fops = {
|
|
|
+ .owner = THIS_MODULE,
|
|
|
+ .llseek = no_llseek,
|
|
|
+ .write = booke_wdt_write,
|
|
|
+ .ioctl = booke_wdt_ioctl,
|
|
|
+ .open = booke_wdt_open,
|
|
|
+};
|
|
|
+
|
|
|
+static struct miscdevice booke_wdt_miscdev = {
|
|
|
+ .minor = WATCHDOG_MINOR,
|
|
|
+ .name = "watchdog",
|
|
|
+ .fops = &booke_wdt_fops,
|
|
|
+};
|
|
|
+
|
|
|
+static void __exit booke_wdt_exit(void)
|
|
|
+{
|
|
|
+ misc_deregister(&booke_wdt_miscdev);
|
|
|
+}
|
|
|
+
|
|
|
+/*
|
|
|
+ * booke_wdt_init:
|
|
|
+ */
|
|
|
+static int __init booke_wdt_init(void)
|
|
|
+{
|
|
|
+ int ret = 0;
|
|
|
+
|
|
|
+ printk (KERN_INFO "PowerPC Book-E Watchdog Timer Loaded\n");
|
|
|
+ ident.firmware_version = cpu_specs[0].pvr_value;
|
|
|
+
|
|
|
+ ret = misc_register(&booke_wdt_miscdev);
|
|
|
+ if (ret) {
|
|
|
+ printk (KERN_CRIT "Cannot register miscdev on minor=%d (err=%d)\n",
|
|
|
+ WATCHDOG_MINOR, ret);
|
|
|
+ return ret;
|
|
|
+ }
|
|
|
+
|
|
|
+ if (wdt_enable == 1) {
|
|
|
+ printk (KERN_INFO "PowerPC Book-E Watchdog Timer Enabled (wdt_period=%d)\n",
|
|
|
+ wdt_period);
|
|
|
+ booke_wdt_enable();
|
|
|
+ }
|
|
|
+
|
|
|
+ return ret;
|
|
|
+}
|
|
|
+device_initcall(booke_wdt_init);
|
Kumar Gala