--- /dev/null
+/*
+ * Watchdog driver for CSR SiRFprimaII and SiRFatlasVI
+ *
+ * Copyright (c) 2013 Cambridge Silicon Radio Limited, a CSR plc group company.
+ *
+ * Licensed under GPLv2 or later.
+ */
+
+#include <linux/module.h>
+#include <linux/watchdog.h>
+#include <linux/platform_device.h>
+#include <linux/moduleparam.h>
+#include <linux/of.h>
+#include <linux/io.h>
+#include <linux/uaccess.h>
+
+#define SIRFSOC_TIMER_COUNTER_LO 0x0000
+#define SIRFSOC_TIMER_MATCH_0 0x0008
+#define SIRFSOC_TIMER_INT_EN 0x0024
+#define SIRFSOC_TIMER_WATCHDOG_EN 0x0028
+#define SIRFSOC_TIMER_LATCH 0x0030
+#define SIRFSOC_TIMER_LATCHED_LO 0x0034
+
+#define SIRFSOC_TIMER_WDT_INDEX 5
+
+#define SIRFSOC_WDT_MIN_TIMEOUT 30 /* 30 secs */
+#define SIRFSOC_WDT_MAX_TIMEOUT (10 * 60) /* 10 mins */
+#define SIRFSOC_WDT_DEFAULT_TIMEOUT 30 /* 30 secs */
+
+static unsigned int timeout = SIRFSOC_WDT_DEFAULT_TIMEOUT;
+static bool nowayout = WATCHDOG_NOWAYOUT;
+
+module_param(timeout, uint, 0);
+module_param(nowayout, bool, 0);
+
+MODULE_PARM_DESC(timeout, "Default watchdog timeout (in seconds)");
+MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
+ __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
+
+static unsigned int sirfsoc_wdt_gettimeleft(struct watchdog_device *wdd)
+{
+ u32 counter, match;
+ void __iomem *wdt_base;
+ int time_left;
+
+ wdt_base = watchdog_get_drvdata(wdd);
+ counter = readl(wdt_base + SIRFSOC_TIMER_COUNTER_LO);
+ match = readl(wdt_base +
+ SIRFSOC_TIMER_MATCH_0 + (SIRFSOC_TIMER_WDT_INDEX << 2));
+
+ time_left = match - counter;
+
+ return time_left / CLOCK_TICK_RATE;
+}
+
+static int sirfsoc_wdt_updatetimeout(struct watchdog_device *wdd)
+{
+ u32 counter, timeout_ticks;
+ void __iomem *wdt_base;
+
+ timeout_ticks = wdd->timeout * CLOCK_TICK_RATE;
+ wdt_base = watchdog_get_drvdata(wdd);
+
+ /* Enable the latch before reading the LATCH_LO register */
+ writel(1, wdt_base + SIRFSOC_TIMER_LATCH);
+
+ /* Set the TO value */
+ counter = readl(wdt_base + SIRFSOC_TIMER_LATCHED_LO);
+
+ counter += timeout_ticks;
+
+ writel(counter, wdt_base +
+ SIRFSOC_TIMER_MATCH_0 + (SIRFSOC_TIMER_WDT_INDEX << 2));
+
+ return 0;
+}
+
+static int sirfsoc_wdt_enable(struct watchdog_device *wdd)
+{
+ void __iomem *wdt_base = watchdog_get_drvdata(wdd);
+ sirfsoc_wdt_updatetimeout(wdd);
+
+ /*
+ * NOTE: If interrupt is not enabled
+ * then WD-Reset doesn't get generated at all.
+ */
+ writel(readl(wdt_base + SIRFSOC_TIMER_INT_EN)
+ | (1 << SIRFSOC_TIMER_WDT_INDEX),
+ wdt_base + SIRFSOC_TIMER_INT_EN);
+ writel(1, wdt_base + SIRFSOC_TIMER_WATCHDOG_EN);
+
+ return 0;
+}
+
+static int sirfsoc_wdt_disable(struct watchdog_device *wdd)
+{
+ void __iomem *wdt_base = watchdog_get_drvdata(wdd);
+
+ writel(0, wdt_base + SIRFSOC_TIMER_WATCHDOG_EN);
+ writel(readl(wdt_base + SIRFSOC_TIMER_INT_EN)
+ & (~(1 << SIRFSOC_TIMER_WDT_INDEX)),
+ wdt_base + SIRFSOC_TIMER_INT_EN);
+
+ return 0;
+}
+
+static int sirfsoc_wdt_settimeout(struct watchdog_device *wdd, unsigned int to)
+{
+ wdd->timeout = to;
+ sirfsoc_wdt_updatetimeout(wdd);
+
+ return 0;
+}
+
+#define OPTIONS (WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE)
+
+static const struct watchdog_info sirfsoc_wdt_ident = {
+ .options = OPTIONS,
+ .firmware_version = 0,
+ .identity = "SiRFSOC Watchdog",
+};
+
+static struct watchdog_ops sirfsoc_wdt_ops = {
+ .owner = THIS_MODULE,
+ .start = sirfsoc_wdt_enable,
+ .stop = sirfsoc_wdt_disable,
+ .get_timeleft = sirfsoc_wdt_gettimeleft,
+ .ping = sirfsoc_wdt_updatetimeout,
+ .set_timeout = sirfsoc_wdt_settimeout,
+};
+
+static struct watchdog_device sirfsoc_wdd = {
+ .info = &sirfsoc_wdt_ident,
+ .ops = &sirfsoc_wdt_ops,
+ .timeout = SIRFSOC_WDT_DEFAULT_TIMEOUT,
+ .min_timeout = SIRFSOC_WDT_MIN_TIMEOUT,
+ .max_timeout = SIRFSOC_WDT_MAX_TIMEOUT,
+};
+
+static int sirfsoc_wdt_probe(struct platform_device *pdev)
+{
+ struct resource *res;
+ int ret;
+ void __iomem *base;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ base = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(base))
+ return PTR_ERR(base);
+
+ watchdog_set_drvdata(&sirfsoc_wdd, base);
+
+ watchdog_init_timeout(&sirfsoc_wdd, timeout, &pdev->dev);
+ watchdog_set_nowayout(&sirfsoc_wdd, nowayout);
+
+ ret = watchdog_register_device(&sirfsoc_wdd);
+ if (ret)
+ return ret;
+
+ platform_set_drvdata(pdev, &sirfsoc_wdd);
+
+ return 0;
+}
+
+static void sirfsoc_wdt_shutdown(struct platform_device *pdev)
+{
+ struct watchdog_device *wdd = platform_get_drvdata(pdev);
+
+ sirfsoc_wdt_disable(wdd);
+}
+
+static int sirfsoc_wdt_remove(struct platform_device *pdev)
+{
+ sirfsoc_wdt_shutdown(pdev);
+ return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int sirfsoc_wdt_suspend(struct device *dev)
+{
+ return 0;
+}
+
+static int sirfsoc_wdt_resume(struct device *dev)
+{
+ struct watchdog_device *wdd = dev_get_drvdata(dev);
+
+ /*
+ * NOTE: Since timer controller registers settings are saved
+ * and restored back by the timer-prima2.c, so we need not
+ * update WD settings except refreshing timeout.
+ */
+ sirfsoc_wdt_updatetimeout(wdd);
+
+ return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(sirfsoc_wdt_pm_ops,
+ sirfsoc_wdt_suspend, sirfsoc_wdt_resume);
+
+static const struct of_device_id sirfsoc_wdt_of_match[] = {
+ { .compatible = "sirf,prima2-tick"},
+ {},
+};
+MODULE_DEVICE_TABLE(of, sirfsoc_wdt_of_match);
+
+static struct platform_driver sirfsoc_wdt_driver = {
+ .driver = {
+ .name = "sirfsoc-wdt",
+ .owner = THIS_MODULE,
+ .pm = &sirfsoc_wdt_pm_ops,
+ .of_match_table = of_match_ptr(sirfsoc_wdt_of_match),
+ },
+ .probe = sirfsoc_wdt_probe,
+ .remove = sirfsoc_wdt_remove,
+ .shutdown = sirfsoc_wdt_shutdown,
+};
+module_platform_driver(sirfsoc_wdt_driver);
+
+MODULE_DESCRIPTION("SiRF SoC watchdog driver");
+MODULE_AUTHOR("Xianglong Du <Xianglong.Du@csr.com>");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:sirfsoc-wdt");
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