--- /dev/null
+/*
+ * Watchdog implementation for GPI h/w found on PMC-Sierra RM9xxx
+ * chips.
+ *
+ * Copyright (C) 2004 by Basler Vision Technologies AG
+ * Author: Thomas Koeller <thomas.koeller@baslerweb.com>
+ *
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#include <linux/platform_device.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/interrupt.h>
+#include <linux/fs.h>
+#include <linux/reboot.h>
+#include <linux/miscdevice.h>
+#include <linux/watchdog.h>
+#include <asm/io.h>
+#include <asm/atomic.h>
+#include <asm/processor.h>
+#include <asm/uaccess.h>
+#include <asm/system.h>
+#include <asm/rm9k-ocd.h>
+
+#include <rm9k_wdt.h>
+
+
+#define CLOCK 125000000
+#define MAX_TIMEOUT_SECONDS 32
+#define CPCCR 0x0080
+#define CPGIG1SR 0x0044
+#define CPGIG1ER 0x0054
+
+
+
+/* Function prototypes */
+static int __init wdt_gpi_probe(struct device *);
+static int __exit wdt_gpi_remove(struct device *);
+static void wdt_gpi_set_timeout(unsigned int);
+static int wdt_gpi_open(struct inode *, struct file *);
+static int wdt_gpi_release(struct inode *, struct file *);
+static ssize_t wdt_gpi_write(struct file *, const char __user *, size_t, loff_t *);
+static long wdt_gpi_ioctl(struct file *, unsigned int, unsigned long);
+static const struct resource *wdt_gpi_get_resource(struct platform_device *, const char *, unsigned int);
+static int wdt_gpi_notify(struct notifier_block *, unsigned long, void *);
+static irqreturn_t wdt_gpi_irqhdl(int, void *, struct pt_regs *);
+
+
+
+
+static const char wdt_gpi_name[] = "wdt_gpi";
+static atomic_t opencnt;
+static int expect_close;
+static int locked = 0;
+
+
+
+/* These are set from device resources */
+static void __iomem * wd_regs;
+static unsigned int wd_irq, wd_ctr;
+
+
+
+/* Module arguments */
+static int timeout = MAX_TIMEOUT_SECONDS;
+module_param(timeout, int, 0444);
+static unsigned long resetaddr = 0xbffdc200;
+module_param(resetaddr, ulong, 0444);
+static unsigned long flagaddr = 0xbffdc104;
+module_param(flagaddr, ulong, 0444);
+static int powercycle = 0;
+module_param(powercycle, bool, 0444);
+
+static int nowayout = WATCHDOG_NOWAYOUT;
+module_param(nowayout, bool, 0444);
+
+
+
+static struct file_operations fops = {
+ .owner = THIS_MODULE,
+ .open = wdt_gpi_open,
+ .release = wdt_gpi_release,
+ .write = wdt_gpi_write,
+ .unlocked_ioctl = wdt_gpi_ioctl,
+};
+
+static struct miscdevice miscdev = {
+ .minor = WATCHDOG_MINOR,
+ .name = wdt_gpi_name,
+ .fops = &fops,
+};
+
+static struct device_driver wdt_gpi_driver = {
+ .name = (char *) wdt_gpi_name,
+ .bus = &platform_bus_type,
+ .owner = THIS_MODULE,
+ .probe = wdt_gpi_probe,
+ .remove = __exit_p(wdt_gpi_remove),
+ .shutdown = NULL,
+ .suspend = NULL,
+ .resume = NULL,
+};
+
+static struct notifier_block wdt_gpi_shutdown = {
+ .notifier_call = wdt_gpi_notify,
+};
+
+
+
+static const struct resource *
+wdt_gpi_get_resource(struct platform_device *pdv, const char *name,
+ unsigned int type)
+{
+ char buf[80];
+ if (snprintf(buf, sizeof buf, "%s_0", name) >= sizeof buf)
+ return NULL;
+ return platform_get_resource_byname(pdv, type, buf);
+}
+
+
+
+/* No hotplugging on the platform bus - use __init */
+static int __init wdt_gpi_probe(struct device *dev)
+{
+ int res;
+ struct platform_device * const pdv = to_platform_device(dev);
+ const struct resource
+ * const rr = wdt_gpi_get_resource(pdv, WDT_RESOURCE_REGS,
+ IORESOURCE_MEM),
+ * const ri = wdt_gpi_get_resource(pdv, WDT_RESOURCE_IRQ,
+ IORESOURCE_IRQ),
+ * const rc = wdt_gpi_get_resource(pdv, WDT_RESOURCE_COUNTER,
+ 0);
+
+ if (unlikely(!rr || !ri || !rc))
+ return -ENXIO;
+
+ wd_regs = ioremap_nocache(rr->start, rr->end + 1 - rr->start);
+ if (unlikely(!wd_regs))
+ return -ENOMEM;
+ wd_irq = ri->start;
+ wd_ctr = rc->start;
+ res = misc_register(&miscdev);
+ if (res)
+ iounmap(wd_regs);
+ else
+ register_reboot_notifier(&wdt_gpi_shutdown);
+ return res;
+}
+
+
+
+static int __exit wdt_gpi_remove(struct device *dev)
+{
+ int res;
+
+ unregister_reboot_notifier(&wdt_gpi_shutdown);
+ res = misc_deregister(&miscdev);
+ iounmap(wd_regs);
+ wd_regs = NULL;
+ return res;
+}
+
+
+static void wdt_gpi_set_timeout(unsigned int to)
+{
+ u32 reg;
+ const u32 wdval = (to * CLOCK) & ~0x0000000f;
+
+ lock_titan_regs();
+ reg = titan_readl(CPCCR) & ~(0xf << (wd_ctr * 4));
+ titan_writel(reg, CPCCR);
+ wmb();
+ __raw_writel(wdval, wd_regs + 0x0000);
+ wmb();
+ titan_writel(reg | (0x2 << (wd_ctr * 4)), CPCCR);
+ wmb();
+ titan_writel(reg | (0x5 << (wd_ctr * 4)), CPCCR);
+ iob();
+ unlock_titan_regs();
+}
+
+
+
+static int wdt_gpi_open(struct inode *i, struct file *f)
+{
+ int res;
+ u32 reg;
+
+ if (unlikely(0 > atomic_dec_if_positive(&opencnt)))
+ return -EBUSY;
+
+ expect_close = 0;
+ if (locked) {
+ module_put(THIS_MODULE);
+ free_irq(wd_irq, &miscdev);
+ locked = 0;
+ }
+
+ res = request_irq(wd_irq, wdt_gpi_irqhdl, SA_SHIRQ | SA_INTERRUPT,
+ wdt_gpi_name, &miscdev);
+ if (unlikely(res))
+ return res;
+
+ wdt_gpi_set_timeout(timeout);
+
+ lock_titan_regs();
+ reg = titan_readl(CPGIG1ER);
+ titan_writel(reg | (0x100 << wd_ctr), CPGIG1ER);
+ iob();
+ unlock_titan_regs();
+
+ printk(KERN_INFO "%s: watchdog started, timeout = %u seconds\n",
+ wdt_gpi_name, timeout);
+ return 0;
+}
+
+
+
+static int wdt_gpi_release(struct inode *i, struct file *f)
+{
+ if (nowayout) {
+ printk(KERN_NOTICE "%s: no way out - watchdog left running\n",
+ wdt_gpi_name);
+ __module_get(THIS_MODULE);
+ locked = 1;
+ } else {
+ if (expect_close) {
+ u32 reg;
+
+ lock_titan_regs();
+ reg = titan_readl(CPCCR) & ~(0xf << (wd_ctr * 4));
+ titan_writel(reg, CPCCR);
+ reg = titan_readl(CPGIG1ER);
+ titan_writel(reg & ~(0x100 << wd_ctr), CPGIG1ER);
+ iob();
+ unlock_titan_regs();
+ free_irq(wd_irq, &miscdev);
+ printk(KERN_INFO "%s: watchdog stopped\n", wdt_gpi_name);
+ } else {
+ printk(KERN_NOTICE "%s: unexpected close() -"
+ " watchdog left running\n",
+ wdt_gpi_name);
+ wdt_gpi_set_timeout(timeout);
+ __module_get(THIS_MODULE);
+ locked = 1;
+ }
+ }
+
+ atomic_inc(&opencnt);
+ return 0;
+}
+
+
+
+static ssize_t
+wdt_gpi_write(struct file *f, const char __user *d, size_t s, loff_t *o)
+{
+ char val;
+
+ wdt_gpi_set_timeout(timeout);
+ expect_close = (s > 0) && !get_user(val, d) && (val == 'V');
+ return s ? 1 : 0;
+}
+
+
+
+static long
+wdt_gpi_ioctl(struct file *f, unsigned int cmd, unsigned long arg)
+{
+ long res = -ENOTTY;
+ const long size = _IOC_SIZE(cmd);
+ int stat;
+ static struct watchdog_info wdinfo = {
+ .identity = "RM9xxx/GPI watchdog",
+ .firmware_version = 0,
+ .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING
+ };
+
+ if (unlikely(_IOC_TYPE(cmd) != WATCHDOG_IOCTL_BASE))
+ return -ENOTTY;
+
+ if ((_IOC_DIR(cmd) & _IOC_READ)
+ && !access_ok(VERIFY_WRITE, arg, size))
+ return -EFAULT;
+
+ if ((_IOC_DIR(cmd) & _IOC_WRITE)
+ && !access_ok(VERIFY_READ, arg, size))
+ return -EFAULT;
+
+ expect_close = 0;
+
+ switch (cmd) {
+ case WDIOC_GETSUPPORT:
+ wdinfo.options = nowayout ?
+ WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING :
+ WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE;
+ res = __copy_to_user((void __user *)arg, &wdinfo, size) ?
+ -EFAULT : size;
+ break;
+
+ case WDIOC_GETSTATUS:
+ break;
+
+ case WDIOC_GETBOOTSTATUS:
+ stat = (*(volatile char *) flagaddr & 0x01)
+ ? WDIOF_CARDRESET : 0;
+ res = __copy_to_user((void __user *)arg, &stat, size) ?
+ -EFAULT : size;
+ break;
+
+ case WDIOC_SETOPTIONS:
+ break;
+
+ case WDIOC_KEEPALIVE:
+ wdt_gpi_set_timeout(timeout);
+ res = size;
+ break;
+
+ case WDIOC_SETTIMEOUT:
+ {
+ int val;
+ if (unlikely(__copy_from_user(&val, (const void __user *) arg,
+ size))) {
+ res = -EFAULT;
+ break;
+ }
+
+ if (val > 32)
+ val = 32;
+ timeout = val;
+ wdt_gpi_set_timeout(val);
+ res = size;
+ printk("%s: timeout set to %u seconds\n",
+ wdt_gpi_name, timeout);
+ }
+ break;
+
+ case WDIOC_GETTIMEOUT:
+ res = __copy_to_user((void __user *) arg, &timeout, size) ?
+ -EFAULT : size;
+ break;
+ }
+
+ return res;
+}
+
+
+
+
+static irqreturn_t wdt_gpi_irqhdl(int irq, void *ctxt, struct pt_regs *regs)
+{
+ if (!unlikely(__raw_readl(wd_regs + 0x0008) & 0x1))
+ return IRQ_NONE;
+ __raw_writel(0x1, wd_regs + 0x0008);
+
+
+ printk(KERN_WARNING "%s: watchdog expired - resetting system\n",
+ wdt_gpi_name);
+
+ *(volatile char *) flagaddr |= 0x01;
+ *(volatile char *) resetaddr = powercycle ? 0x01 : 0x2;
+ iob();
+ while (1)
+ cpu_relax();
+}
+
+
+
+static int
+wdt_gpi_notify(struct notifier_block *this, unsigned long code, void *unused)
+{
+ if(code == SYS_DOWN || code == SYS_HALT) {
+ u32 reg;
+
+ lock_titan_regs();
+ reg = titan_readl(CPCCR) & ~(0xf << (wd_ctr * 4));
+ titan_writel(reg, CPCCR);
+ reg = titan_readl(CPGIG1ER);
+ titan_writel(reg & ~(0x100 << wd_ctr), CPGIG1ER);
+ iob();
+ unlock_titan_regs();
+ }
+ return NOTIFY_DONE;
+}
+
+
+
+static int __init wdt_gpi_init_module(void)
+{
+ atomic_set(&opencnt, 1);
+ if (timeout > MAX_TIMEOUT_SECONDS)
+ timeout = MAX_TIMEOUT_SECONDS;
+ return driver_register(&wdt_gpi_driver);
+}
+
+
+
+static void __exit wdt_gpi_cleanup_module(void)
+{
+ driver_unregister(&wdt_gpi_driver);
+}
+
+module_init(wdt_gpi_init_module);
+module_exit(wdt_gpi_cleanup_module);
+
+
+
+MODULE_AUTHOR("Thomas Koeller <thomas.koeller@baslerweb.com>");
+MODULE_DESCRIPTION("Basler eXcite watchdog driver for gpi devices");
+MODULE_VERSION("0.1");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
+MODULE_PARM_DESC(timeout, "Watchdog timeout in seconds");
+MODULE_PARM_DESC(resetaddr, "Address to write to to force a reset");
+MODULE_PARM_DESC(flagaddr, "Address to write to boot flags to");
+MODULE_PARM_DESC(nowayout, "Watchdog cannot be disabled once started");
+MODULE_PARM_DESC(powercycle, "Cycle power if watchdog expires");
projects / linux-2.6-omap-h63xx.git / commitdiff