Adding upstream version 6.1.76.upstream/6.1.76upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 353 insertions, 0 deletions

diff --git a/drivers/watchdog/i6300esb.c b/drivers/watchdog/i6300esb.c
new file mode 100644
index 000000000..a30835f54
--- /dev/null
+++ b/drivers/watchdog/i6300esb.c
@@ -0,0 +1,353 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *	i6300esb:	Watchdog timer driver for Intel 6300ESB chipset
+ *
+ *	(c) Copyright 2004 Google Inc.
+ *	(c) Copyright 2005 David Härdeman <david@2gen.com>
+ *
+ *	based on i810-tco.c which is in turn based on softdog.c
+ *
+ *	The timer is implemented in the following I/O controller hubs:
+ *	(See the intel documentation on http://developer.intel.com.)
+ *	6300ESB chip : document number 300641-004
+ *
+ *  2004YYZZ Ross Biro
+ *	Initial version 0.01
+ *  2004YYZZ Ross Biro
+ *	Version 0.02
+ *  20050210 David Härdeman <david@2gen.com>
+ *	Ported driver to kernel 2.6
+ *  20171016 Radu Rendec <rrendec@arista.com>
+ *	Change driver to use the watchdog subsystem
+ *	Add support for multiple 6300ESB devices
+ */
+
+/*
+ *      Includes, defines, variables, module parameters, ...
+ */
+
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/fs.h>
+#include <linux/mm.h>
+#include <linux/miscdevice.h>
+#include <linux/watchdog.h>
+#include <linux/pci.h>
+#include <linux/ioport.h>
+#include <linux/uaccess.h>
+#include <linux/io.h>
+
+/* Module and version information */
+#define ESB_MODULE_NAME "i6300ESB timer"
+
+/* PCI configuration registers */
+#define ESB_CONFIG_REG  0x60            /* Config register                   */
+#define ESB_LOCK_REG    0x68            /* WDT lock register                 */
+
+/* Memory mapped registers */
+#define ESB_TIMER1_REG(w) ((w)->base + 0x00)/* Timer1 value after each reset */
+#define ESB_TIMER2_REG(w) ((w)->base + 0x04)/* Timer2 value after each reset */
+#define ESB_GINTSR_REG(w) ((w)->base + 0x08)/* General Interrupt Status Reg  */
+#define ESB_RELOAD_REG(w) ((w)->base + 0x0c)/* Reload register               */
+
+/* Lock register bits */
+#define ESB_WDT_FUNC    (0x01 << 2)   /* Watchdog functionality            */
+#define ESB_WDT_ENABLE  (0x01 << 1)   /* Enable WDT                        */
+#define ESB_WDT_LOCK    (0x01 << 0)   /* Lock (nowayout)                   */
+
+/* Config register bits */
+#define ESB_WDT_REBOOT  (0x01 << 5)   /* Enable reboot on timeout          */
+#define ESB_WDT_FREQ    (0x01 << 2)   /* Decrement frequency               */
+#define ESB_WDT_INTTYPE (0x03 << 0)   /* Interrupt type on timer1 timeout  */
+
+/* Reload register bits */
+#define ESB_WDT_TIMEOUT (0x01 << 9)    /* Watchdog timed out                */
+#define ESB_WDT_RELOAD  (0x01 << 8)    /* prevent timeout                   */
+
+/* Magic constants */
+#define ESB_UNLOCK1     0x80            /* Step 1 to unlock reset registers  */
+#define ESB_UNLOCK2     0x86            /* Step 2 to unlock reset registers  */
+
+/* module parameters */
+/* 30 sec default heartbeat (1 < heartbeat < 2*1023) */
+#define ESB_HEARTBEAT_MIN	1
+#define ESB_HEARTBEAT_MAX	2046
+#define ESB_HEARTBEAT_DEFAULT	30
+#define ESB_HEARTBEAT_RANGE __MODULE_STRING(ESB_HEARTBEAT_MIN) \
+	"<heartbeat<" __MODULE_STRING(ESB_HEARTBEAT_MAX)
+static int heartbeat; /* in seconds */
+module_param(heartbeat, int, 0);
+MODULE_PARM_DESC(heartbeat,
+	"Watchdog heartbeat in seconds. (" ESB_HEARTBEAT_RANGE
+	", default=" __MODULE_STRING(ESB_HEARTBEAT_DEFAULT) ")");
+
+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) ")");
+
+/* internal variables */
+struct esb_dev {
+	struct watchdog_device wdd;
+	void __iomem *base;
+	struct pci_dev *pdev;
+};
+
+#define to_esb_dev(wptr) container_of(wptr, struct esb_dev, wdd)
+
+/*
+ * Some i6300ESB specific functions
+ */
+
+/*
+ * Prepare for reloading the timer by unlocking the proper registers.
+ * This is performed by first writing 0x80 followed by 0x86 to the
+ * reload register. After this the appropriate registers can be written
+ * to once before they need to be unlocked again.
+ */
+static inline void esb_unlock_registers(struct esb_dev *edev)
+{
+	writew(ESB_UNLOCK1, ESB_RELOAD_REG(edev));
+	writew(ESB_UNLOCK2, ESB_RELOAD_REG(edev));
+}
+
+static int esb_timer_start(struct watchdog_device *wdd)
+{
+	struct esb_dev *edev = to_esb_dev(wdd);
+	int _wdd_nowayout = test_bit(WDOG_NO_WAY_OUT, &wdd->status);
+	u8 val;
+
+	esb_unlock_registers(edev);
+	writew(ESB_WDT_RELOAD, ESB_RELOAD_REG(edev));
+	/* Enable or Enable + Lock? */
+	val = ESB_WDT_ENABLE | (_wdd_nowayout ? ESB_WDT_LOCK : 0x00);
+	pci_write_config_byte(edev->pdev, ESB_LOCK_REG, val);
+	return 0;
+}
+
+static int esb_timer_stop(struct watchdog_device *wdd)
+{
+	struct esb_dev *edev = to_esb_dev(wdd);
+	u8 val;
+
+	/* First, reset timers as suggested by the docs */
+	esb_unlock_registers(edev);
+	writew(ESB_WDT_RELOAD, ESB_RELOAD_REG(edev));
+	/* Then disable the WDT */
+	pci_write_config_byte(edev->pdev, ESB_LOCK_REG, 0x0);
+	pci_read_config_byte(edev->pdev, ESB_LOCK_REG, &val);
+
+	/* Returns 0 if the timer was disabled, non-zero otherwise */
+	return val & ESB_WDT_ENABLE;
+}
+
+static int esb_timer_keepalive(struct watchdog_device *wdd)
+{
+	struct esb_dev *edev = to_esb_dev(wdd);
+
+	esb_unlock_registers(edev);
+	writew(ESB_WDT_RELOAD, ESB_RELOAD_REG(edev));
+	/* FIXME: Do we need to flush anything here? */
+	return 0;
+}
+
+static int esb_timer_set_heartbeat(struct watchdog_device *wdd,
+		unsigned int time)
+{
+	struct esb_dev *edev = to_esb_dev(wdd);
+	u32 val;
+
+	/* We shift by 9, so if we are passed a value of 1 sec,
+	 * val will be 1 << 9 = 512, then write that to two
+	 * timers => 2 * 512 = 1024 (which is decremented at 1KHz)
+	 */
+	val = time << 9;
+
+	/* Write timer 1 */
+	esb_unlock_registers(edev);
+	writel(val, ESB_TIMER1_REG(edev));
+
+	/* Write timer 2 */
+	esb_unlock_registers(edev);
+	writel(val, ESB_TIMER2_REG(edev));
+
+	/* Reload */
+	esb_unlock_registers(edev);
+	writew(ESB_WDT_RELOAD, ESB_RELOAD_REG(edev));
+
+	/* FIXME: Do we need to flush everything out? */
+
+	/* Done */
+	wdd->timeout = time;
+	return 0;
+}
+
+/*
+ * Watchdog Subsystem Interfaces
+ */
+
+static struct watchdog_info esb_info = {
+	.identity = ESB_MODULE_NAME,
+	.options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
+};
+
+static const struct watchdog_ops esb_ops = {
+	.owner = THIS_MODULE,
+	.start = esb_timer_start,
+	.stop = esb_timer_stop,
+	.set_timeout = esb_timer_set_heartbeat,
+	.ping = esb_timer_keepalive,
+};
+
+/*
+ * Data for PCI driver interface
+ */
+static const struct pci_device_id esb_pci_tbl[] = {
+	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ESB_9), },
+	{ 0, },                 /* End of list */
+};
+MODULE_DEVICE_TABLE(pci, esb_pci_tbl);
+
+/*
+ *      Init & exit routines
+ */
+
+static unsigned char esb_getdevice(struct esb_dev *edev)
+{
+	if (pci_enable_device(edev->pdev)) {
+		dev_err(&edev->pdev->dev, "failed to enable device\n");
+		goto err_devput;
+	}
+
+	if (pci_request_region(edev->pdev, 0, ESB_MODULE_NAME)) {
+		dev_err(&edev->pdev->dev, "failed to request region\n");
+		goto err_disable;
+	}
+
+	edev->base = pci_ioremap_bar(edev->pdev, 0);
+	if (edev->base == NULL) {
+		/* Something's wrong here, BASEADDR has to be set */
+		dev_err(&edev->pdev->dev, "failed to get BASEADDR\n");
+		goto err_release;
+	}
+
+	/* Done */
+	dev_set_drvdata(&edev->pdev->dev, edev);
+	return 1;
+
+err_release:
+	pci_release_region(edev->pdev, 0);
+err_disable:
+	pci_disable_device(edev->pdev);
+err_devput:
+	return 0;
+}
+
+static void esb_initdevice(struct esb_dev *edev)
+{
+	u8 val1;
+	u16 val2;
+
+	/*
+	 * Config register:
+	 * Bit    5 : 0 = Enable WDT_OUTPUT
+	 * Bit    2 : 0 = set the timer frequency to the PCI clock
+	 * divided by 2^15 (approx 1KHz).
+	 * Bits 1:0 : 11 = WDT_INT_TYPE Disabled.
+	 * The watchdog has two timers, it can be setup so that the
+	 * expiry of timer1 results in an interrupt and the expiry of
+	 * timer2 results in a reboot. We set it to not generate
+	 * any interrupts as there is not much we can do with it
+	 * right now.
+	 */
+	pci_write_config_word(edev->pdev, ESB_CONFIG_REG, 0x0003);
+
+	/* Check that the WDT isn't already locked */
+	pci_read_config_byte(edev->pdev, ESB_LOCK_REG, &val1);
+	if (val1 & ESB_WDT_LOCK)
+		dev_warn(&edev->pdev->dev, "nowayout already set\n");
+
+	/* Set the timer to watchdog mode and disable it for now */
+	pci_write_config_byte(edev->pdev, ESB_LOCK_REG, 0x00);
+
+	/* Check if the watchdog was previously triggered */
+	esb_unlock_registers(edev);
+	val2 = readw(ESB_RELOAD_REG(edev));
+	if (val2 & ESB_WDT_TIMEOUT)
+		edev->wdd.bootstatus = WDIOF_CARDRESET;
+
+	/* Reset WDT_TIMEOUT flag and timers */
+	esb_unlock_registers(edev);
+	writew((ESB_WDT_TIMEOUT | ESB_WDT_RELOAD), ESB_RELOAD_REG(edev));
+
+	/* And set the correct timeout value */
+	esb_timer_set_heartbeat(&edev->wdd, edev->wdd.timeout);
+}
+
+static int esb_probe(struct pci_dev *pdev,
+		const struct pci_device_id *ent)
+{
+	struct esb_dev *edev;
+	int ret;
+
+	edev = devm_kzalloc(&pdev->dev, sizeof(*edev), GFP_KERNEL);
+	if (!edev)
+		return -ENOMEM;
+
+	/* Check whether or not the hardware watchdog is there */
+	edev->pdev = pdev;
+	if (!esb_getdevice(edev))
+		return -ENODEV;
+
+	/* Initialize the watchdog and make sure it does not run */
+	edev->wdd.info = &esb_info;
+	edev->wdd.ops = &esb_ops;
+	edev->wdd.min_timeout = ESB_HEARTBEAT_MIN;
+	edev->wdd.max_timeout = ESB_HEARTBEAT_MAX;
+	edev->wdd.timeout = ESB_HEARTBEAT_DEFAULT;
+	watchdog_init_timeout(&edev->wdd, heartbeat, NULL);
+	watchdog_set_nowayout(&edev->wdd, nowayout);
+	watchdog_stop_on_reboot(&edev->wdd);
+	watchdog_stop_on_unregister(&edev->wdd);
+	esb_initdevice(edev);
+
+	/* Register the watchdog so that userspace has access to it */
+	ret = watchdog_register_device(&edev->wdd);
+	if (ret != 0)
+		goto err_unmap;
+	dev_info(&pdev->dev,
+		"initialized. heartbeat=%d sec (nowayout=%d)\n",
+		edev->wdd.timeout, nowayout);
+	return 0;
+
+err_unmap:
+	iounmap(edev->base);
+	pci_release_region(edev->pdev, 0);
+	pci_disable_device(edev->pdev);
+	return ret;
+}
+
+static void esb_remove(struct pci_dev *pdev)
+{
+	struct esb_dev *edev = dev_get_drvdata(&pdev->dev);
+
+	watchdog_unregister_device(&edev->wdd);
+	iounmap(edev->base);
+	pci_release_region(edev->pdev, 0);
+	pci_disable_device(edev->pdev);
+}
+
+static struct pci_driver esb_driver = {
+	.name		= ESB_MODULE_NAME,
+	.id_table	= esb_pci_tbl,
+	.probe          = esb_probe,
+	.remove         = esb_remove,
+};
+
+module_pci_driver(esb_driver);
+
+MODULE_AUTHOR("Ross Biro and David Härdeman");
+MODULE_DESCRIPTION("Watchdog driver for Intel 6300ESB chipsets");
+MODULE_LICENSE("GPL");