1 files changed, 510 insertions, 0 deletions

diff --git a/drivers/watchdog/sp5100_tco.c b/drivers/watchdog/sp5100_tco.c
new file mode 100644
index 000000000..0db77c90b
--- /dev/null
+++ b/drivers/watchdog/sp5100_tco.c
@@ -0,0 +1,510 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *	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.
+ *				https://www.kernelconcepts.de
+ *
+ *	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"
+ *	    AMD Publication 55570-B1-PUB "Processor Programming Reference (PPR)
+ *				for AMD Family 17h Model 18h, Revision B1
+ *				Processors (PUB)
+ *	    AMD Publication 55772-A1-PUB "Processor Programming Reference (PPR)
+ *				for AMD Family 17h Model 20h, Revision A1
+ *				Processors (PUB)
+ */
+
+/*
+ *	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));
+
+	/* This must be a distinct write. */
+	val |= SP5100_WDT_TRIGGER_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;
+		/*
+		 * On Family 17h devices, the EFCH_PM_DECODEEN_WDT_TMREN bit of
+		 * EFCH_PM_DECODEEN not only enables the EFCH_PM_WDT_ADDR memory
+		 * region, it also enables the watchdog itself.
+		 */
+		if (boot_cpu_data.x86 == 0x17) {
+			val = sp5100_tco_read_pm_reg8(EFCH_PM_DECODEEN);
+			if (!(val & EFCH_PM_DECODEEN_WDT_TMREN)) {
+				sp5100_tco_update_pm_reg8(EFCH_PM_DECODEEN, 0xff,
+							  EFCH_PM_DECODEEN_WDT_TMREN);
+			}
+		}
+		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;
+
+	watchdog_init_timeout(wdd, heartbeat, NULL);
+	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)
+		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");