Adding upstream version 6.6.15.upstream/6.6.15

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

1 files changed, 247 insertions, 0 deletions

diff --git a/drivers/watchdog/bcm2835_wdt.c b/drivers/watchdog/bcm2835_wdt.c
new file mode 100644
index 0000000000..bb001c5d7f
--- /dev/null
+++ b/drivers/watchdog/bcm2835_wdt.c
@@ -0,0 +1,247 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Watchdog driver for Broadcom BCM2835
+ *
+ * "bcm2708_wdog" driver written by Luke Diamand that was obtained from
+ * branch "rpi-3.6.y" of git://github.com/raspberrypi/linux.git was used
+ * as a hardware reference for the Broadcom BCM2835 watchdog timer.
+ *
+ * Copyright (C) 2013 Lubomir Rintel <lkundrak@v3.sk>
+ *
+ */
+
+#include <linux/delay.h>
+#include <linux/types.h>
+#include <linux/mfd/bcm2835-pm.h>
+#include <linux/module.h>
+#include <linux/io.h>
+#include <linux/watchdog.h>
+#include <linux/platform_device.h>
+#include <linux/of_address.h>
+#include <linux/of_platform.h>
+
+#define PM_RSTC				0x1c
+#define PM_RSTS				0x20
+#define PM_WDOG				0x24
+
+#define PM_PASSWORD			0x5a000000
+
+#define PM_WDOG_TIME_SET		0x000fffff
+#define PM_RSTC_WRCFG_CLR		0xffffffcf
+#define PM_RSTS_HADWRH_SET		0x00000040
+#define PM_RSTC_WRCFG_SET		0x00000030
+#define PM_RSTC_WRCFG_FULL_RESET	0x00000020
+#define PM_RSTC_RESET			0x00000102
+
+/*
+ * The Raspberry Pi firmware uses the RSTS register to know which partition
+ * to boot from. The partition value is spread into bits 0, 2, 4, 6, 8, 10.
+ * Partition 63 is a special partition used by the firmware to indicate halt.
+ */
+#define PM_RSTS_RASPBERRYPI_HALT	0x555
+
+#define SECS_TO_WDOG_TICKS(x) ((x) << 16)
+#define WDOG_TICKS_TO_SECS(x) ((x) >> 16)
+#define WDOG_TICKS_TO_MSECS(x) ((x) * 1000 >> 16)
+
+struct bcm2835_wdt {
+	void __iomem		*base;
+	spinlock_t		lock;
+};
+
+static struct bcm2835_wdt *bcm2835_power_off_wdt;
+
+static unsigned int heartbeat;
+static bool nowayout = WATCHDOG_NOWAYOUT;
+
+static bool bcm2835_wdt_is_running(struct bcm2835_wdt *wdt)
+{
+	uint32_t cur;
+
+	cur = readl(wdt->base + PM_RSTC);
+
+	return !!(cur & PM_RSTC_WRCFG_FULL_RESET);
+}
+
+static int bcm2835_wdt_start(struct watchdog_device *wdog)
+{
+	struct bcm2835_wdt *wdt = watchdog_get_drvdata(wdog);
+	uint32_t cur;
+	unsigned long flags;
+
+	spin_lock_irqsave(&wdt->lock, flags);
+
+	writel_relaxed(PM_PASSWORD | (SECS_TO_WDOG_TICKS(wdog->timeout) &
+				PM_WDOG_TIME_SET), wdt->base + PM_WDOG);
+	cur = readl_relaxed(wdt->base + PM_RSTC);
+	writel_relaxed(PM_PASSWORD | (cur & PM_RSTC_WRCFG_CLR) |
+		  PM_RSTC_WRCFG_FULL_RESET, wdt->base + PM_RSTC);
+
+	spin_unlock_irqrestore(&wdt->lock, flags);
+
+	return 0;
+}
+
+static int bcm2835_wdt_stop(struct watchdog_device *wdog)
+{
+	struct bcm2835_wdt *wdt = watchdog_get_drvdata(wdog);
+
+	writel_relaxed(PM_PASSWORD | PM_RSTC_RESET, wdt->base + PM_RSTC);
+	return 0;
+}
+
+static unsigned int bcm2835_wdt_get_timeleft(struct watchdog_device *wdog)
+{
+	struct bcm2835_wdt *wdt = watchdog_get_drvdata(wdog);
+
+	uint32_t ret = readl_relaxed(wdt->base + PM_WDOG);
+	return WDOG_TICKS_TO_SECS(ret & PM_WDOG_TIME_SET);
+}
+
+static void __bcm2835_restart(struct bcm2835_wdt *wdt)
+{
+	u32 val;
+
+	/* use a timeout of 10 ticks (~150us) */
+	writel_relaxed(10 | PM_PASSWORD, wdt->base + PM_WDOG);
+	val = readl_relaxed(wdt->base + PM_RSTC);
+	val &= PM_RSTC_WRCFG_CLR;
+	val |= PM_PASSWORD | PM_RSTC_WRCFG_FULL_RESET;
+	writel_relaxed(val, wdt->base + PM_RSTC);
+
+	/* No sleeping, possibly atomic. */
+	mdelay(1);
+}
+
+static int bcm2835_restart(struct watchdog_device *wdog,
+			   unsigned long action, void *data)
+{
+	struct bcm2835_wdt *wdt = watchdog_get_drvdata(wdog);
+
+	__bcm2835_restart(wdt);
+
+	return 0;
+}
+
+static const struct watchdog_ops bcm2835_wdt_ops = {
+	.owner =	THIS_MODULE,
+	.start =	bcm2835_wdt_start,
+	.stop =		bcm2835_wdt_stop,
+	.get_timeleft =	bcm2835_wdt_get_timeleft,
+	.restart =	bcm2835_restart,
+};
+
+static const struct watchdog_info bcm2835_wdt_info = {
+	.options =	WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE |
+			WDIOF_KEEPALIVEPING,
+	.identity =	"Broadcom BCM2835 Watchdog timer",
+};
+
+static struct watchdog_device bcm2835_wdt_wdd = {
+	.info =		&bcm2835_wdt_info,
+	.ops =		&bcm2835_wdt_ops,
+	.min_timeout =	1,
+	.max_hw_heartbeat_ms =	WDOG_TICKS_TO_MSECS(PM_WDOG_TIME_SET),
+	.timeout =	WDOG_TICKS_TO_SECS(PM_WDOG_TIME_SET),
+};
+
+/*
+ * We can't really power off, but if we do the normal reset scheme, and
+ * indicate to bootcode.bin not to reboot, then most of the chip will be
+ * powered off.
+ */
+static void bcm2835_power_off(void)
+{
+	struct bcm2835_wdt *wdt = bcm2835_power_off_wdt;
+	u32 val;
+
+	/*
+	 * We set the watchdog hard reset bit here to distinguish this reset
+	 * from the normal (full) reset. bootcode.bin will not reboot after a
+	 * hard reset.
+	 */
+	val = readl_relaxed(wdt->base + PM_RSTS);
+	val |= PM_PASSWORD | PM_RSTS_RASPBERRYPI_HALT;
+	writel_relaxed(val, wdt->base + PM_RSTS);
+
+	/* Continue with normal reset mechanism */
+	__bcm2835_restart(wdt);
+}
+
+static int bcm2835_wdt_probe(struct platform_device *pdev)
+{
+	struct bcm2835_pm *pm = dev_get_drvdata(pdev->dev.parent);
+	struct device *dev = &pdev->dev;
+	struct bcm2835_wdt *wdt;
+	int err;
+
+	wdt = devm_kzalloc(dev, sizeof(struct bcm2835_wdt), GFP_KERNEL);
+	if (!wdt)
+		return -ENOMEM;
+
+	spin_lock_init(&wdt->lock);
+
+	wdt->base = pm->base;
+
+	watchdog_set_drvdata(&bcm2835_wdt_wdd, wdt);
+	watchdog_init_timeout(&bcm2835_wdt_wdd, heartbeat, dev);
+	watchdog_set_nowayout(&bcm2835_wdt_wdd, nowayout);
+	bcm2835_wdt_wdd.parent = dev;
+	if (bcm2835_wdt_is_running(wdt)) {
+		/*
+		 * The currently active timeout value (set by the
+		 * bootloader) may be different from the module
+		 * heartbeat parameter or the value in device
+		 * tree. But we just need to set WDOG_HW_RUNNING,
+		 * because then the framework will "immediately" ping
+		 * the device, updating the timeout.
+		 */
+		set_bit(WDOG_HW_RUNNING, &bcm2835_wdt_wdd.status);
+	}
+
+	watchdog_set_restart_priority(&bcm2835_wdt_wdd, 128);
+
+	watchdog_stop_on_reboot(&bcm2835_wdt_wdd);
+	err = devm_watchdog_register_device(dev, &bcm2835_wdt_wdd);
+	if (err)
+		return err;
+
+	if (of_device_is_system_power_controller(pdev->dev.parent->of_node)) {
+		if (!pm_power_off) {
+			pm_power_off = bcm2835_power_off;
+			bcm2835_power_off_wdt = wdt;
+		} else {
+			dev_info(dev, "Poweroff handler already present!\n");
+		}
+	}
+
+	dev_info(dev, "Broadcom BCM2835 watchdog timer");
+	return 0;
+}
+
+static void bcm2835_wdt_remove(struct platform_device *pdev)
+{
+	if (pm_power_off == bcm2835_power_off)
+		pm_power_off = NULL;
+}
+
+static struct platform_driver bcm2835_wdt_driver = {
+	.probe		= bcm2835_wdt_probe,
+	.remove_new	= bcm2835_wdt_remove,
+	.driver = {
+		.name =		"bcm2835-wdt",
+	},
+};
+module_platform_driver(bcm2835_wdt_driver);
+
+module_param(heartbeat, uint, 0);
+MODULE_PARM_DESC(heartbeat, "Initial watchdog heartbeat in seconds");
+
+module_param(nowayout, bool, 0);
+MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
+				__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
+
+MODULE_ALIAS("platform:bcm2835-wdt");
+MODULE_AUTHOR("Lubomir Rintel <lkundrak@v3.sk>");
+MODULE_DESCRIPTION("Driver for Broadcom BCM2835 watchdog timer");
+MODULE_LICENSE("GPL");