--- /dev/null
+/*
+ * sp5100_tco : TCO timer driver for sp5100 chipsets
+ *
+ * (c) Copyright 2009 Google Inc., All Rights Reserved.
+ *
+ * Based on i8xx_tco.c:
+ * (c) Copyright 2000 kernel concepts <nils@kernelconcepts.de>, All Rights
+ * Reserved.
+ * http://www.kernelconcepts.de
+ *
+ * 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.
+ *
+ * See AMD Publication 43009 "AMD SB700/710/750 Register Reference Guide"
+ */
+
+/*
+ * Includes, defines, variables, module parameters, ...
+ */
+
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/types.h>
+#include <linux/miscdevice.h>
+#include <linux/watchdog.h>
+#include <linux/init.h>
+#include <linux/fs.h>
+#include <linux/pci.h>
+#include <linux/ioport.h>
+#include <linux/platform_device.h>
+#include <linux/uaccess.h>
+#include <linux/io.h>
+
+#include "sp5100_tco.h"
+
+/* Module and version information */
+#define TCO_VERSION "0.01"
+#define TCO_MODULE_NAME "SP5100 TCO timer"
+#define TCO_DRIVER_NAME TCO_MODULE_NAME ", v" TCO_VERSION
+#define PFX TCO_MODULE_NAME ": "
+
+/* internal variables */
+static void __iomem *tcobase;
+static unsigned int pm_iobase;
+static DEFINE_SPINLOCK(tco_lock); /* Guards the hardware */
+static unsigned long timer_alive;
+static char tco_expect_close;
+static struct pci_dev *sp5100_tco_pci;
+
+/* the watchdog platform device */
+static struct platform_device *sp5100_tco_platform_device;
+
+/* module parameters */
+
+#define WATCHDOG_HEARTBEAT 60 /* 60 sec default heartbeat. */
+static int heartbeat = WATCHDOG_HEARTBEAT; /* in seconds */
+module_param(heartbeat, int, 0);
+MODULE_PARM_DESC(heartbeat, "Watchdog heartbeat in seconds. (default="
+ __MODULE_STRING(WATCHDOG_HEARTBEAT) ")");
+
+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) ")");
+
+/*
+ * Some TCO specific functions
+ */
+static void tco_timer_start(void)
+{
+ u32 val;
+ unsigned long flags;
+
+ spin_lock_irqsave(&tco_lock, flags);
+ val = readl(SP5100_WDT_CONTROL(tcobase));
+ val |= SP5100_WDT_START_STOP_BIT;
+ writel(val, SP5100_WDT_CONTROL(tcobase));
+ spin_unlock_irqrestore(&tco_lock, flags);
+}
+
+static void tco_timer_stop(void)
+{
+ u32 val;
+ unsigned long flags;
+
+ spin_lock_irqsave(&tco_lock, flags);
+ val = readl(SP5100_WDT_CONTROL(tcobase));
+ val &= ~SP5100_WDT_START_STOP_BIT;
+ writel(val, SP5100_WDT_CONTROL(tcobase));
+ spin_unlock_irqrestore(&tco_lock, flags);
+}
+
+static void tco_timer_keepalive(void)
+{
+ u32 val;
+ unsigned long flags;
+
+ spin_lock_irqsave(&tco_lock, flags);
+ val = readl(SP5100_WDT_CONTROL(tcobase));
+ val |= SP5100_WDT_TRIGGER_BIT;
+ writel(val, SP5100_WDT_CONTROL(tcobase));
+ spin_unlock_irqrestore(&tco_lock, flags);
+}
+
+static int tco_timer_set_heartbeat(int t)
+{
+ unsigned long flags;
+
+ if (t < 0 || t > 0xffff)
+ return -EINVAL;
+
+ /* Write new heartbeat to watchdog */
+ spin_lock_irqsave(&tco_lock, flags);
+ writel(t, SP5100_WDT_COUNT(tcobase));
+ spin_unlock_irqrestore(&tco_lock, flags);
+
+ heartbeat = t;
+ return 0;
+}
+
+/*
+ * /dev/watchdog handling
+ */
+
+static int sp5100_tco_open(struct inode *inode, struct file *file)
+{
+ /* /dev/watchdog can only be opened once */
+ if (test_and_set_bit(0, &timer_alive))
+ return -EBUSY;
+
+ /* Reload and activate timer */
+ tco_timer_start();
+ tco_timer_keepalive();
+ return nonseekable_open(inode, file);
+}
+
+static int sp5100_tco_release(struct inode *inode, struct file *file)
+{
+ /* Shut off the timer. */
+ if (tco_expect_close == 42) {
+ tco_timer_stop();
+ } else {
+ printk(KERN_CRIT PFX
+ "Unexpected close, not stopping watchdog!\n");
+ tco_timer_keepalive();
+ }
+ clear_bit(0, &timer_alive);
+ tco_expect_close = 0;
+ return 0;
+}
+
+static ssize_t sp5100_tco_write(struct file *file, const char __user *data,
+ size_t len, loff_t *ppos)
+{
+ /* See if we got the magic character 'V' and reload the timer */
+ if (len) {
+ if (!nowayout) {
+ size_t i;
+
+ /* note: just in case someone wrote the magic character
+ * five months ago... */
+ tco_expect_close = 0;
+
+ /* scan to see whether or not we got the magic character
+ */
+ for (i = 0; i != len; i++) {
+ char c;
+ if (get_user(c, data + i))
+ return -EFAULT;
+ if (c == 'V')
+ tco_expect_close = 42;
+ }
+ }
+
+ /* someone wrote to us, we should reload the timer */
+ tco_timer_keepalive();
+ }
+ return len;
+}
+
+static long sp5100_tco_ioctl(struct file *file, unsigned int cmd,
+ unsigned long arg)
+{
+ int new_options, retval = -EINVAL;
+ int new_heartbeat;
+ void __user *argp = (void __user *)arg;
+ int __user *p = argp;
+ static const struct watchdog_info ident = {
+ .options = WDIOF_SETTIMEOUT |
+ WDIOF_KEEPALIVEPING |
+ WDIOF_MAGICCLOSE,
+ .firmware_version = 0,
+ .identity = TCO_MODULE_NAME,
+ };
+
+ switch (cmd) {
+ case WDIOC_GETSUPPORT:
+ return copy_to_user(argp, &ident,
+ sizeof(ident)) ? -EFAULT : 0;
+ case WDIOC_GETSTATUS:
+ case WDIOC_GETBOOTSTATUS:
+ return put_user(0, p);
+ case WDIOC_SETOPTIONS:
+ if (get_user(new_options, p))
+ return -EFAULT;
+ if (new_options & WDIOS_DISABLECARD) {
+ tco_timer_stop();
+ retval = 0;
+ }
+ if (new_options & WDIOS_ENABLECARD) {
+ tco_timer_start();
+ tco_timer_keepalive();
+ retval = 0;
+ }
+ return retval;
+ case WDIOC_KEEPALIVE:
+ tco_timer_keepalive();
+ return 0;
+ case WDIOC_SETTIMEOUT:
+ if (get_user(new_heartbeat, p))
+ return -EFAULT;
+ if (tco_timer_set_heartbeat(new_heartbeat))
+ return -EINVAL;
+ tco_timer_keepalive();
+ /* Fall through */
+ case WDIOC_GETTIMEOUT:
+ return put_user(heartbeat, p);
+ default:
+ return -ENOTTY;
+ }
+}
+
+/*
+ * Kernel Interfaces
+ */
+
+static const struct file_operations sp5100_tco_fops = {
+ .owner = THIS_MODULE,
+ .llseek = no_llseek,
+ .write = sp5100_tco_write,
+ .unlocked_ioctl = sp5100_tco_ioctl,
+ .open = sp5100_tco_open,
+ .release = sp5100_tco_release,
+};
+
+static struct miscdevice sp5100_tco_miscdev = {
+ .minor = WATCHDOG_MINOR,
+ .name = "watchdog",
+ .fops = &sp5100_tco_fops,
+};
+
+/*
+ * Data for PCI driver interface
+ *
+ * This data only exists for exporting the supported
+ * PCI ids via MODULE_DEVICE_TABLE. We do not actually
+ * register a pci_driver, because someone else might
+ * want to register another driver on the same PCI id.
+ */
+static struct pci_device_id sp5100_tco_pci_tbl[] = {
+ { PCI_VENDOR_ID_ATI, PCI_DEVICE_ID_ATI_SBX00_SMBUS, PCI_ANY_ID,
+ PCI_ANY_ID, },
+ { 0, }, /* End of list */
+};
+MODULE_DEVICE_TABLE(pci, sp5100_tco_pci_tbl);
+
+/*
+ * Init & exit routines
+ */
+
+static unsigned char __devinit sp5100_tco_setupdevice(void)
+{
+ struct pci_dev *dev = NULL;
+ u32 val;
+
+ /* Match the PCI device */
+ for_each_pci_dev(dev) {
+ if (pci_match_id(sp5100_tco_pci_tbl, dev) != NULL) {
+ sp5100_tco_pci = dev;
+ break;
+ }
+ }
+
+ if (!sp5100_tco_pci)
+ return 0;
+
+ /* Request the IO ports used by this driver */
+ pm_iobase = SP5100_IO_PM_INDEX_REG;
+ if (!request_region(pm_iobase, SP5100_PM_IOPORTS_SIZE, "SP5100 TCO")) {
+ printk(KERN_ERR PFX "I/O address 0x%04x already in use\n",
+ pm_iobase);
+ goto exit;
+ }
+
+ /* Find the watchdog base address. */
+ outb(SP5100_PM_WATCHDOG_BASE3, SP5100_IO_PM_INDEX_REG);
+ val = inb(SP5100_IO_PM_DATA_REG);
+ outb(SP5100_PM_WATCHDOG_BASE2, SP5100_IO_PM_INDEX_REG);
+ val = val << 8 | inb(SP5100_IO_PM_DATA_REG);
+ outb(SP5100_PM_WATCHDOG_BASE1, SP5100_IO_PM_INDEX_REG);
+ val = val << 8 | inb(SP5100_IO_PM_DATA_REG);
+ outb(SP5100_PM_WATCHDOG_BASE0, SP5100_IO_PM_INDEX_REG);
+ /* Low three bits of BASE0 are reserved. */
+ val = val << 8 | (inb(SP5100_IO_PM_DATA_REG) & 0xf8);
+
+ tcobase = ioremap(val, SP5100_WDT_MEM_MAP_SIZE);
+ if (tcobase == 0) {
+ printk(KERN_ERR PFX "failed to get tcobase address\n");
+ goto unreg_region;
+ }
+
+ /* Enable watchdog decode bit */
+ pci_read_config_dword(sp5100_tco_pci,
+ SP5100_PCI_WATCHDOG_MISC_REG,
+ &val);
+
+ val |= SP5100_PCI_WATCHDOG_DECODE_EN;
+
+ pci_write_config_dword(sp5100_tco_pci,
+ SP5100_PCI_WATCHDOG_MISC_REG,
+ val);
+
+ /* Enable Watchdog timer and set the resolution to 1 sec. */
+ outb(SP5100_PM_WATCHDOG_CONTROL, SP5100_IO_PM_INDEX_REG);
+ val = inb(SP5100_IO_PM_DATA_REG);
+ val |= SP5100_PM_WATCHDOG_SECOND_RES;
+ val &= ~SP5100_PM_WATCHDOG_DISABLE;
+ outb(val, SP5100_IO_PM_DATA_REG);
+
+ /* Check that the watchdog action is set to reset the system. */
+ val = readl(SP5100_WDT_CONTROL(tcobase));
+ val &= ~SP5100_PM_WATCHDOG_ACTION_RESET;
+ writel(val, SP5100_WDT_CONTROL(tcobase));
+
+ /* Set a reasonable heartbeat before we stop the timer */
+ tco_timer_set_heartbeat(heartbeat);
+
+ /*
+ * Stop the TCO before we change anything so we don't race with
+ * a zeroed timer.
+ */
+ tco_timer_stop();
+
+ /* Done */
+ return 1;
+
+ iounmap(tcobase);
+unreg_region:
+ release_region(pm_iobase, SP5100_PM_IOPORTS_SIZE);
+exit:
+ return 0;
+}
+
+static int __devinit sp5100_tco_init(struct platform_device *dev)
+{
+ int ret;
+ u32 val;
+
+ /* Check whether or not the hardware watchdog is there. If found, then
+ * set it up.
+ */
+ if (!sp5100_tco_setupdevice())
+ return -ENODEV;
+
+ /* Check to see if last reboot was due to watchdog timeout */
+ printk(KERN_INFO PFX "Watchdog reboot %sdetected.\n",
+ readl(SP5100_WDT_CONTROL(tcobase)) & SP5100_PM_WATCHDOG_FIRED ?
+ "" : "not ");
+
+ /* Clear out the old status */
+ val = readl(SP5100_WDT_CONTROL(tcobase));
+ val &= ~SP5100_PM_WATCHDOG_FIRED;
+ writel(val, SP5100_WDT_CONTROL(tcobase));
+
+ /*
+ * Check that the heartbeat value is within it's range.
+ * If not, reset to the default.
+ */
+ if (tco_timer_set_heartbeat(heartbeat)) {
+ heartbeat = WATCHDOG_HEARTBEAT;
+ tco_timer_set_heartbeat(heartbeat);
+ }
+
+ ret = misc_register(&sp5100_tco_miscdev);
+ if (ret != 0) {
+ printk(KERN_ERR PFX "cannot register miscdev on minor="
+ "%d (err=%d)\n",
+ WATCHDOG_MINOR, ret);
+ goto exit;
+ }
+
+ clear_bit(0, &timer_alive);
+
+ printk(KERN_INFO PFX "initialized (0x%p). heartbeat=%d sec"
+ " (nowayout=%d)\n",
+ tcobase, heartbeat, nowayout);
+
+ return 0;
+
+exit:
+ iounmap(tcobase);
+ release_region(pm_iobase, SP5100_PM_IOPORTS_SIZE);
+ return ret;
+}
+
+static void __devexit sp5100_tco_cleanup(void)
+{
+ /* Stop the timer before we leave */
+ if (!nowayout)
+ tco_timer_stop();
+
+ /* Deregister */
+ misc_deregister(&sp5100_tco_miscdev);
+ iounmap(tcobase);
+ release_region(pm_iobase, SP5100_PM_IOPORTS_SIZE);
+}
+
+static int __devexit sp5100_tco_remove(struct platform_device *dev)
+{
+ if (tcobase)
+ sp5100_tco_cleanup();
+ return 0;
+}
+
+static void sp5100_tco_shutdown(struct platform_device *dev)
+{
+ tco_timer_stop();
+}
+
+static struct platform_driver sp5100_tco_driver = {
+ .probe = sp5100_tco_init,
+ .remove = __devexit_p(sp5100_tco_remove),
+ .shutdown = sp5100_tco_shutdown,
+ .driver = {
+ .owner = THIS_MODULE,
+ .name = TCO_MODULE_NAME,
+ },
+};
+
+static int __init sp5100_tco_init_module(void)
+{
+ int err;
+
+ printk(KERN_INFO PFX "SP5100 TCO WatchDog Timer Driver v%s\n",
+ TCO_VERSION);
+
+ err = platform_driver_register(&sp5100_tco_driver);
+ if (err)
+ return err;
+
+ sp5100_tco_platform_device = platform_device_register_simple(
+ TCO_MODULE_NAME, -1, NULL, 0);
+ if (IS_ERR(sp5100_tco_platform_device)) {
+ err = PTR_ERR(sp5100_tco_platform_device);
+ goto unreg_platform_driver;
+ }
+
+ return 0;
+
+unreg_platform_driver:
+ platform_driver_unregister(&sp5100_tco_driver);
+ return err;
+}
+
+static void __exit sp5100_tco_cleanup_module(void)
+{
+ platform_device_unregister(sp5100_tco_platform_device);
+ platform_driver_unregister(&sp5100_tco_driver);
+ printk(KERN_INFO PFX "SP5100 TCO Watchdog Module Unloaded.\n");
+}
+
+module_init(sp5100_tco_init_module);
+module_exit(sp5100_tco_cleanup_module);
+
+MODULE_AUTHOR("Priyanka Gupta");
+MODULE_DESCRIPTION("TCO timer driver for SP5100 chipset");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
projects / mv-sheeva.git / blobdiff