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-rw-r--r--drivers/watchdog/sp5100_tco.c496
1 files changed, 496 insertions, 0 deletions
diff --git a/drivers/watchdog/sp5100_tco.c b/drivers/watchdog/sp5100_tco.c
new file mode 100644
index 000000000..41aaae2d5
--- /dev/null
+++ b/drivers/watchdog/sp5100_tco.c
@@ -0,0 +1,496 @@
+/*
+ * 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",
+ * AMD Publication 45482 "AMD SB800-Series Southbridges Register
+ * Reference Guide"
+ * AMD Publication 48751 "BIOS and Kernel Developer’s Guide (BKDG)
+ * for AMD Family 16h Models 00h-0Fh Processors"
+ * AMD Publication 51192 "AMD Bolton FCH Register Reference Guide"
+ * AMD Publication 52740 "BIOS and Kernel Developer’s Guide (BKDG)
+ * for AMD Family 16h Models 30h-3Fh Processors"
+ */
+
+/*
+ * Includes, defines, variables, module parameters, ...
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/ioport.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/pci.h>
+#include <linux/platform_device.h>
+#include <linux/types.h>
+#include <linux/watchdog.h>
+
+#include "sp5100_tco.h"
+
+#define TCO_DRIVER_NAME "sp5100-tco"
+
+/* internal variables */
+
+enum tco_reg_layout {
+ sp5100, sb800, efch
+};
+
+struct sp5100_tco {
+ struct watchdog_device wdd;
+ void __iomem *tcobase;
+ enum tco_reg_layout tco_reg_layout;
+};
+
+/* the watchdog platform device */
+static struct platform_device *sp5100_tco_platform_device;
+/* the associated PCI device */
+static struct pci_dev *sp5100_tco_pci;
+
+/* 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 bool nowayout = WATCHDOG_NOWAYOUT;
+module_param(nowayout, bool, 0);
+MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started."
+ " (default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
+
+/*
+ * Some TCO specific functions
+ */
+
+static enum tco_reg_layout tco_reg_layout(struct pci_dev *dev)
+{
+ if (dev->vendor == PCI_VENDOR_ID_ATI &&
+ dev->device == PCI_DEVICE_ID_ATI_SBX00_SMBUS &&
+ dev->revision < 0x40) {
+ return sp5100;
+ } else if (dev->vendor == PCI_VENDOR_ID_AMD &&
+ ((dev->device == PCI_DEVICE_ID_AMD_HUDSON2_SMBUS &&
+ dev->revision >= 0x41) ||
+ (dev->device == PCI_DEVICE_ID_AMD_KERNCZ_SMBUS &&
+ dev->revision >= 0x49))) {
+ return efch;
+ }
+ return sb800;
+}
+
+static int tco_timer_start(struct watchdog_device *wdd)
+{
+ struct sp5100_tco *tco = watchdog_get_drvdata(wdd);
+ u32 val;
+
+ val = readl(SP5100_WDT_CONTROL(tco->tcobase));
+ val |= SP5100_WDT_START_STOP_BIT;
+ writel(val, SP5100_WDT_CONTROL(tco->tcobase));
+
+ return 0;
+}
+
+static int tco_timer_stop(struct watchdog_device *wdd)
+{
+ struct sp5100_tco *tco = watchdog_get_drvdata(wdd);
+ u32 val;
+
+ val = readl(SP5100_WDT_CONTROL(tco->tcobase));
+ val &= ~SP5100_WDT_START_STOP_BIT;
+ writel(val, SP5100_WDT_CONTROL(tco->tcobase));
+
+ return 0;
+}
+
+static int tco_timer_ping(struct watchdog_device *wdd)
+{
+ struct sp5100_tco *tco = watchdog_get_drvdata(wdd);
+ u32 val;
+
+ val = readl(SP5100_WDT_CONTROL(tco->tcobase));
+ val |= SP5100_WDT_TRIGGER_BIT;
+ writel(val, SP5100_WDT_CONTROL(tco->tcobase));
+
+ return 0;
+}
+
+static int tco_timer_set_timeout(struct watchdog_device *wdd,
+ unsigned int t)
+{
+ struct sp5100_tco *tco = watchdog_get_drvdata(wdd);
+
+ /* Write new heartbeat to watchdog */
+ writel(t, SP5100_WDT_COUNT(tco->tcobase));
+
+ wdd->timeout = t;
+
+ return 0;
+}
+
+static u8 sp5100_tco_read_pm_reg8(u8 index)
+{
+ outb(index, SP5100_IO_PM_INDEX_REG);
+ return inb(SP5100_IO_PM_DATA_REG);
+}
+
+static void sp5100_tco_update_pm_reg8(u8 index, u8 reset, u8 set)
+{
+ u8 val;
+
+ outb(index, SP5100_IO_PM_INDEX_REG);
+ val = inb(SP5100_IO_PM_DATA_REG);
+ val &= reset;
+ val |= set;
+ outb(val, SP5100_IO_PM_DATA_REG);
+}
+
+static void tco_timer_enable(struct sp5100_tco *tco)
+{
+ u32 val;
+
+ switch (tco->tco_reg_layout) {
+ case sb800:
+ /* For SB800 or later */
+ /* Set the Watchdog timer resolution to 1 sec */
+ sp5100_tco_update_pm_reg8(SB800_PM_WATCHDOG_CONFIG,
+ 0xff, SB800_PM_WATCHDOG_SECOND_RES);
+
+ /* Enable watchdog decode bit and watchdog timer */
+ sp5100_tco_update_pm_reg8(SB800_PM_WATCHDOG_CONTROL,
+ ~SB800_PM_WATCHDOG_DISABLE,
+ SB800_PCI_WATCHDOG_DECODE_EN);
+ break;
+ case sp5100:
+ /* For SP5100 or SB7x0 */
+ /* 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 */
+ sp5100_tco_update_pm_reg8(SP5100_PM_WATCHDOG_CONTROL,
+ ~SP5100_PM_WATCHDOG_DISABLE,
+ SP5100_PM_WATCHDOG_SECOND_RES);
+ break;
+ case efch:
+ /* Set the Watchdog timer resolution to 1 sec and enable */
+ sp5100_tco_update_pm_reg8(EFCH_PM_DECODEEN3,
+ ~EFCH_PM_WATCHDOG_DISABLE,
+ EFCH_PM_DECODEEN_SECOND_RES);
+ break;
+ }
+}
+
+static u32 sp5100_tco_read_pm_reg32(u8 index)
+{
+ u32 val = 0;
+ int i;
+
+ for (i = 3; i >= 0; i--)
+ val = (val << 8) + sp5100_tco_read_pm_reg8(index + i);
+
+ return val;
+}
+
+static int sp5100_tco_setupdevice(struct device *dev,
+ struct watchdog_device *wdd)
+{
+ struct sp5100_tco *tco = watchdog_get_drvdata(wdd);
+ const char *dev_name;
+ u32 mmio_addr = 0, val;
+ int ret;
+
+ /* Request the IO ports used by this driver */
+ if (!request_muxed_region(SP5100_IO_PM_INDEX_REG,
+ SP5100_PM_IOPORTS_SIZE, "sp5100_tco")) {
+ dev_err(dev, "I/O address 0x%04x already in use\n",
+ SP5100_IO_PM_INDEX_REG);
+ return -EBUSY;
+ }
+
+ /*
+ * Determine type of southbridge chipset.
+ */
+ switch (tco->tco_reg_layout) {
+ case sp5100:
+ dev_name = SP5100_DEVNAME;
+ mmio_addr = sp5100_tco_read_pm_reg32(SP5100_PM_WATCHDOG_BASE) &
+ 0xfffffff8;
+ break;
+ case sb800:
+ dev_name = SB800_DEVNAME;
+ mmio_addr = sp5100_tco_read_pm_reg32(SB800_PM_WATCHDOG_BASE) &
+ 0xfffffff8;
+ break;
+ case efch:
+ dev_name = SB800_DEVNAME;
+ val = sp5100_tco_read_pm_reg8(EFCH_PM_DECODEEN);
+ if (val & EFCH_PM_DECODEEN_WDT_TMREN)
+ mmio_addr = EFCH_PM_WDT_ADDR;
+ break;
+ default:
+ return -ENODEV;
+ }
+
+ /* Check MMIO address conflict */
+ if (!mmio_addr ||
+ !devm_request_mem_region(dev, mmio_addr, SP5100_WDT_MEM_MAP_SIZE,
+ dev_name)) {
+ if (mmio_addr)
+ dev_dbg(dev, "MMIO address 0x%08x already in use\n",
+ mmio_addr);
+ switch (tco->tco_reg_layout) {
+ case sp5100:
+ /*
+ * Secondly, Find the watchdog timer MMIO address
+ * from SBResource_MMIO register.
+ */
+ /* Read SBResource_MMIO from PCI config(PCI_Reg: 9Ch) */
+ pci_read_config_dword(sp5100_tco_pci,
+ SP5100_SB_RESOURCE_MMIO_BASE,
+ &mmio_addr);
+ if ((mmio_addr & (SB800_ACPI_MMIO_DECODE_EN |
+ SB800_ACPI_MMIO_SEL)) !=
+ SB800_ACPI_MMIO_DECODE_EN) {
+ ret = -ENODEV;
+ goto unreg_region;
+ }
+ mmio_addr &= ~0xFFF;
+ mmio_addr += SB800_PM_WDT_MMIO_OFFSET;
+ break;
+ case sb800:
+ /* Read SBResource_MMIO from AcpiMmioEn(PM_Reg: 24h) */
+ mmio_addr =
+ sp5100_tco_read_pm_reg32(SB800_PM_ACPI_MMIO_EN);
+ if ((mmio_addr & (SB800_ACPI_MMIO_DECODE_EN |
+ SB800_ACPI_MMIO_SEL)) !=
+ SB800_ACPI_MMIO_DECODE_EN) {
+ ret = -ENODEV;
+ goto unreg_region;
+ }
+ mmio_addr &= ~0xFFF;
+ mmio_addr += SB800_PM_WDT_MMIO_OFFSET;
+ break;
+ case efch:
+ val = sp5100_tco_read_pm_reg8(EFCH_PM_ISACONTROL);
+ if (!(val & EFCH_PM_ISACONTROL_MMIOEN)) {
+ ret = -ENODEV;
+ goto unreg_region;
+ }
+ mmio_addr = EFCH_PM_ACPI_MMIO_ADDR +
+ EFCH_PM_ACPI_MMIO_WDT_OFFSET;
+ break;
+ }
+ dev_dbg(dev, "Got 0x%08x from SBResource_MMIO register\n",
+ mmio_addr);
+ if (!devm_request_mem_region(dev, mmio_addr,
+ SP5100_WDT_MEM_MAP_SIZE,
+ dev_name)) {
+ dev_dbg(dev, "MMIO address 0x%08x already in use\n",
+ mmio_addr);
+ ret = -EBUSY;
+ goto unreg_region;
+ }
+ }
+
+ tco->tcobase = devm_ioremap(dev, mmio_addr, SP5100_WDT_MEM_MAP_SIZE);
+ if (!tco->tcobase) {
+ dev_err(dev, "failed to get tcobase address\n");
+ ret = -ENOMEM;
+ goto unreg_region;
+ }
+
+ dev_info(dev, "Using 0x%08x for watchdog MMIO address\n", mmio_addr);
+
+ /* Setup the watchdog timer */
+ tco_timer_enable(tco);
+
+ val = readl(SP5100_WDT_CONTROL(tco->tcobase));
+ if (val & SP5100_WDT_DISABLED) {
+ dev_err(dev, "Watchdog hardware is disabled\n");
+ ret = -ENODEV;
+ goto unreg_region;
+ }
+
+ /*
+ * Save WatchDogFired status, because WatchDogFired flag is
+ * cleared here.
+ */
+ if (val & SP5100_WDT_FIRED)
+ wdd->bootstatus = WDIOF_CARDRESET;
+ /* Set watchdog action to reset the system */
+ val &= ~SP5100_WDT_ACTION_RESET;
+ writel(val, SP5100_WDT_CONTROL(tco->tcobase));
+
+ /* Set a reasonable heartbeat before we stop the timer */
+ tco_timer_set_timeout(wdd, wdd->timeout);
+
+ /*
+ * Stop the TCO before we change anything so we don't race with
+ * a zeroed timer.
+ */
+ tco_timer_stop(wdd);
+
+ release_region(SP5100_IO_PM_INDEX_REG, SP5100_PM_IOPORTS_SIZE);
+
+ return 0;
+
+unreg_region:
+ release_region(SP5100_IO_PM_INDEX_REG, SP5100_PM_IOPORTS_SIZE);
+ return ret;
+}
+
+static struct watchdog_info sp5100_tco_wdt_info = {
+ .identity = "SP5100 TCO timer",
+ .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
+};
+
+static const struct watchdog_ops sp5100_tco_wdt_ops = {
+ .owner = THIS_MODULE,
+ .start = tco_timer_start,
+ .stop = tco_timer_stop,
+ .ping = tco_timer_ping,
+ .set_timeout = tco_timer_set_timeout,
+};
+
+static int sp5100_tco_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct watchdog_device *wdd;
+ struct sp5100_tco *tco;
+ int ret;
+
+ tco = devm_kzalloc(dev, sizeof(*tco), GFP_KERNEL);
+ if (!tco)
+ return -ENOMEM;
+
+ tco->tco_reg_layout = tco_reg_layout(sp5100_tco_pci);
+
+ wdd = &tco->wdd;
+ wdd->parent = dev;
+ wdd->info = &sp5100_tco_wdt_info;
+ wdd->ops = &sp5100_tco_wdt_ops;
+ wdd->timeout = WATCHDOG_HEARTBEAT;
+ wdd->min_timeout = 1;
+ wdd->max_timeout = 0xffff;
+
+ if (watchdog_init_timeout(wdd, heartbeat, NULL))
+ dev_info(dev, "timeout value invalid, using %d\n",
+ wdd->timeout);
+ watchdog_set_nowayout(wdd, nowayout);
+ watchdog_stop_on_reboot(wdd);
+ watchdog_stop_on_unregister(wdd);
+ watchdog_set_drvdata(wdd, tco);
+
+ ret = sp5100_tco_setupdevice(dev, wdd);
+ if (ret)
+ return ret;
+
+ ret = devm_watchdog_register_device(dev, wdd);
+ if (ret) {
+ dev_err(dev, "cannot register watchdog device (err=%d)\n", ret);
+ return ret;
+ }
+
+ /* Show module parameters */
+ dev_info(dev, "initialized. heartbeat=%d sec (nowayout=%d)\n",
+ wdd->timeout, nowayout);
+
+ return 0;
+}
+
+static struct platform_driver sp5100_tco_driver = {
+ .probe = sp5100_tco_probe,
+ .driver = {
+ .name = TCO_DRIVER_NAME,
+ },
+};
+
+/*
+ * 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 const struct pci_device_id sp5100_tco_pci_tbl[] = {
+ { PCI_VENDOR_ID_ATI, PCI_DEVICE_ID_ATI_SBX00_SMBUS, PCI_ANY_ID,
+ PCI_ANY_ID, },
+ { PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_HUDSON2_SMBUS, PCI_ANY_ID,
+ PCI_ANY_ID, },
+ { PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_KERNCZ_SMBUS, PCI_ANY_ID,
+ PCI_ANY_ID, },
+ { 0, }, /* End of list */
+};
+MODULE_DEVICE_TABLE(pci, sp5100_tco_pci_tbl);
+
+static int __init sp5100_tco_init(void)
+{
+ struct pci_dev *dev = NULL;
+ int err;
+
+ /* 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 -ENODEV;
+
+ pr_info("SP5100/SB800 TCO WatchDog Timer Driver\n");
+
+ err = platform_driver_register(&sp5100_tco_driver);
+ if (err)
+ return err;
+
+ sp5100_tco_platform_device =
+ platform_device_register_simple(TCO_DRIVER_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_exit(void)
+{
+ platform_device_unregister(sp5100_tco_platform_device);
+ platform_driver_unregister(&sp5100_tco_driver);
+}
+
+module_init(sp5100_tco_init);
+module_exit(sp5100_tco_exit);
+
+MODULE_AUTHOR("Priyanka Gupta");
+MODULE_DESCRIPTION("TCO timer driver for SP5100/SB800 chipset");
+MODULE_LICENSE("GPL");