Merge branch 'next' of https://gitlab.denx.de/u-boot/custodians/u-boot-marvell into next

- Handling all DM watchdogs in watchdog_reset() (Rasmus)

arch/sandbox/dts/test.dts

@@ -793,6 +793,13 @@
 		};
 	};
 
+	gpio-wdt {
+		gpios = <&gpio_a 7 0>;
+		compatible = "linux,wdt-gpio";
+		hw_margin_ms = <100>;
+		always-running;
+	};
+
 	mbox: mbox {
 		compatible = "sandbox,mbox";
 		#mbox-cells = <1>;
@@ -1272,6 +1279,7 @@
 
 	wdt0: wdt@0 {
 		compatible = "sandbox,wdt";
+		hw_margin_ms = <200>;
 	};
 
 	axi: axi@0 {

board/alliedtelesis/x530/x530.c

@@ -121,9 +121,8 @@ int board_init(void)
 
 void arch_preboot_os(void)
 {
-#ifdef CONFIG_WATCHDOG
-	wdt_stop(gd->watchdog_dev);
-#endif
+	if (CONFIG_IS_ENABLED(WDT))
+		wdt_stop_all();
 }
 
 static int led_7seg_init(unsigned int segments)

configs/sandbox64_defconfig

@@ -225,7 +225,9 @@ CONFIG_OSD=y
 CONFIG_SANDBOX_OSD=y
 CONFIG_SPLASH_SCREEN_ALIGN=y
 CONFIG_VIDEO_BMP_RLE8=y
+# CONFIG_WATCHDOG_AUTOSTART is not set
 CONFIG_WDT=y
+CONFIG_WDT_GPIO=y
 CONFIG_WDT_SANDBOX=y
 CONFIG_FS_CBFS=y
 CONFIG_FS_CRAMFS=y

configs/sandbox_defconfig

@@ -283,7 +283,9 @@ CONFIG_W1=y
 CONFIG_W1_GPIO=y
 CONFIG_W1_EEPROM=y
 CONFIG_W1_EEPROM_SANDBOX=y
+# CONFIG_WATCHDOG_AUTOSTART is not set
 CONFIG_WDT=y
+CONFIG_WDT_GPIO=y
 CONFIG_WDT_SANDBOX=y
 CONFIG_FS_CBFS=y
 CONFIG_FS_CRAMFS=y

doc/device-tree-bindings/watchdog/gpio-wdt.txt

@@ -0,0 +1,19 @@
+GPIO watchdog timer
+
+Describes a simple watchdog timer which is reset by toggling a gpio.
+
+Required properties:
+
+- compatible: Must be "linux,wdt-gpio".
+- gpios: gpio to toggle when wdt driver reset method is called.
+- always-running: Boolean property indicating that the watchdog cannot
+  be disabled. At present, U-Boot only supports this kind of GPIO
+  watchdog.
+
+Example:
+
+	gpio-wdt {
+		gpios = <&gpio0 1 0>;
+		compatible = "linux,wdt-gpio";
+		always-running;
+	};

drivers/watchdog/Kconfig

@@ -147,6 +147,15 @@ config WDT_CORTINA
 	  This driver support all CPU ISAs supported by Cortina
 	  Access CAxxxx SoCs.
 
+config WDT_GPIO
+	bool "External gpio watchdog support"
+	depends on WDT
+	depends on DM_GPIO
+	help
+	  Support for external watchdog fed by toggling a gpio. See
+	  doc/device-tree-bindings/watchdog/gpio-wdt.txt for
+	  information on how to describe the watchdog in device tree.
+
 config WDT_MPC8xx
 	bool "MPC8xx watchdog timer support"
 	depends on WDT && MPC8xx

drivers/watchdog/Makefile

@@ -25,6 +25,7 @@ obj-$(CONFIG_WDT_BOOKE) += booke_wdt.o
 obj-$(CONFIG_WDT_CORTINA) += cortina_wdt.o
 obj-$(CONFIG_WDT_ORION) += orion_wdt.o
 obj-$(CONFIG_WDT_CDNS) += cdns_wdt.o
+obj-$(CONFIG_WDT_GPIO) += gpio_wdt.o
 obj-$(CONFIG_WDT_MPC8xx) += mpc8xx_wdt.o
 obj-$(CONFIG_WDT_MT7620) += mt7620_wdt.o
 obj-$(CONFIG_WDT_MT7621) += mt7621_wdt.o

drivers/watchdog/gpio_wdt.c

@@ -0,0 +1,68 @@
+// SPDX-License-Identifier: GPL-2.0+
+
+#include <dm.h>
+#include <dm/device_compat.h>
+#include <wdt.h>
+#include <asm/gpio.h>
+
+struct gpio_wdt_priv {
+	struct gpio_desc gpio;
+	bool always_running;
+	int state;
+};
+
+static int gpio_wdt_reset(struct udevice *dev)
+{
+	struct gpio_wdt_priv *priv = dev_get_priv(dev);
+
+	priv->state = !priv->state;
+
+	return dm_gpio_set_value(&priv->gpio, priv->state);
+}
+
+static int gpio_wdt_start(struct udevice *dev, u64 timeout, ulong flags)
+{
+	struct gpio_wdt_priv *priv = dev_get_priv(dev);
+
+	if (priv->always_running)
+		return 0;
+
+	return -ENOSYS;
+}
+
+static int dm_probe(struct udevice *dev)
+{
+	struct gpio_wdt_priv *priv = dev_get_priv(dev);
+	int ret;
+
+	priv->always_running = dev_read_bool(dev, "always-running");
+	ret = gpio_request_by_name(dev, "gpios", 0, &priv->gpio, GPIOD_IS_OUT);
+	if (ret < 0) {
+		dev_err(dev, "Request for wdt gpio failed: %d\n", ret);
+		return ret;
+	}
+
+	if (priv->always_running)
+		ret = gpio_wdt_reset(dev);
+
+	return ret;
+}
+
+static const struct wdt_ops gpio_wdt_ops = {
+	.start = gpio_wdt_start,
+	.reset = gpio_wdt_reset,
+};
+
+static const struct udevice_id gpio_wdt_ids[] = {
+	{ .compatible = "linux,wdt-gpio" },
+	{}
+};
+
+U_BOOT_DRIVER(wdt_gpio) = {
+	.name = "wdt_gpio",
+	.id = UCLASS_WDT,
+	.of_match = gpio_wdt_ids,
+	.ops = &gpio_wdt_ops,
+	.probe	= dm_probe,
+	.priv_auto = sizeof(struct gpio_wdt_priv),
+};

drivers/watchdog/wdt-uclass.c

@@ -20,53 +20,67 @@ DECLARE_GLOBAL_DATA_PTR;
 
 #define WATCHDOG_TIMEOUT_SECS	(CONFIG_WATCHDOG_TIMEOUT_MSECS / 1000)
 
-/*
- * Reset every 1000ms, or however often is required as indicated by a
- * hw_margin_ms property.
- */
-static ulong reset_period = 1000;
+struct wdt_priv {
+	/* Timeout, in seconds, to configure this device to. */
+	u32 timeout;
+	/*
+	 * Time, in milliseconds, between calling the device's ->reset()
+	 * method from watchdog_reset().
+	 */
+	ulong reset_period;
+	/*
+	 * Next time (as returned by get_timer(0)) to call
+	 * ->reset().
+	 */
+	ulong next_reset;
+	/* Whether watchdog_start() has been called on the device. */
+	bool running;
+};
+
+static void init_watchdog_dev(struct udevice *dev)
+{
+	struct wdt_priv *priv;
+	int ret;
+
+	priv = dev_get_uclass_priv(dev);
+
+	if (!IS_ENABLED(CONFIG_WATCHDOG_AUTOSTART)) {
+		printf("WDT:   Not starting %s\n", dev->name);
+		return;
+	}
+
+	ret = wdt_start(dev, priv->timeout * 1000, 0);
+	if (ret != 0) {
+		printf("WDT:   Failed to start %s\n", dev->name);
+		return;
+	}
+
+	printf("WDT:   Started %s with%s servicing (%ds timeout)\n", dev->name,
+	       IS_ENABLED(CONFIG_WATCHDOG) ? "" : "out", priv->timeout);
+}
 
 int initr_watchdog(void)
 {
-	u32 timeout = WATCHDOG_TIMEOUT_SECS;
+	struct udevice *dev;
+	struct uclass *uc;
 	int ret;
 
-	/*
-	 * Init watchdog: This will call the probe function of the
-	 * watchdog driver, enabling the use of the device
-	 */
-	if (uclass_get_device_by_seq(UCLASS_WDT, 0,
-				     (struct udevice **)&gd->watchdog_dev)) {
-		debug("WDT:   Not found by seq!\n");
-		if (uclass_get_device(UCLASS_WDT, 0,
-				      (struct udevice **)&gd->watchdog_dev)) {
-			printf("WDT:   Not found!\n");
-			return 0;
+	ret = uclass_get(UCLASS_WDT, &uc);
+	if (ret) {
+		log_debug("Error getting UCLASS_WDT: %d\n", ret);
+		return 0;
+	}
+
+	uclass_foreach_dev(dev, uc) {
+		ret = device_probe(dev);
+		if (ret) {
+			log_debug("Error probing %s: %d\n", dev->name, ret);
+			continue;
 		}
+		init_watchdog_dev(dev);
 	}
 
-	if (CONFIG_IS_ENABLED(OF_CONTROL) && !CONFIG_IS_ENABLED(OF_PLATDATA)) {
-		timeout = dev_read_u32_default(gd->watchdog_dev, "timeout-sec",
-					       WATCHDOG_TIMEOUT_SECS);
-		reset_period = dev_read_u32_default(gd->watchdog_dev,
-						    "hw_margin_ms",
-						    4 * reset_period) / 4;
-	}
-
-	if (!IS_ENABLED(CONFIG_WATCHDOG_AUTOSTART)) {
-		printf("WDT:   Not starting\n");
-		return 0;
-	}
-
-	ret = wdt_start(gd->watchdog_dev, timeout * 1000, 0);
-	if (ret != 0) {
-		printf("WDT:   Failed to start\n");
-		return 0;
-	}
-
-	printf("WDT:   Started with%s servicing (%ds timeout)\n",
-	       IS_ENABLED(CONFIG_WATCHDOG) ? "" : "out", timeout);
-
+	gd->flags |= GD_FLG_WDT_READY;
 	return 0;
 }
 
@@ -79,8 +93,11 @@ int wdt_start(struct udevice *dev, u64 timeout_ms, ulong flags)
 		return -ENOSYS;
 
 	ret = ops->start(dev, timeout_ms, flags);
-	if (ret == 0)
-		gd->flags |= GD_FLG_WDT_READY;
+	if (ret == 0) {
+		struct wdt_priv *priv = dev_get_uclass_priv(dev);
+
+		priv->running = true;
+	}
 
 	return ret;
 }
@@ -94,8 +111,36 @@ int wdt_stop(struct udevice *dev)
 		return -ENOSYS;
 
 	ret = ops->stop(dev);
-	if (ret == 0)
-		gd->flags &= ~GD_FLG_WDT_READY;
+	if (ret == 0) {
+		struct wdt_priv *priv = dev_get_uclass_priv(dev);
+
+		priv->running = false;
+	}
+
+	return ret;
+}
+
+int wdt_stop_all(void)
+{
+	struct wdt_priv *priv;
+	struct udevice *dev;
+	struct uclass *uc;
+	int ret, err;
+
+	ret = uclass_get(UCLASS_WDT, &uc);
+	if (ret)
+		return ret;
+
+	uclass_foreach_dev(dev, uc) {
+		if (!device_active(dev))
+			continue;
+		priv = dev_get_uclass_priv(dev);
+		if (!priv->running)
+			continue;
+		err = wdt_stop(dev);
+		if (!ret)
+			ret = err;
+	}
 
 	return ret;
 }
@@ -120,10 +165,8 @@ int wdt_expire_now(struct udevice *dev, ulong flags)
 	if (ops->expire_now) {
 		return ops->expire_now(dev, flags);
 	} else {
-		if (!ops->start)
-			return -ENOSYS;
+		ret = wdt_start(dev, 1, flags);
 
-		ret = ops->start(dev, 1, flags);
 		if (ret < 0)
 			return ret;
 
@@ -141,18 +184,36 @@ int wdt_expire_now(struct udevice *dev, ulong flags)
  */
 void watchdog_reset(void)
 {
-	static ulong next_reset;
+	struct wdt_priv *priv;
+	struct udevice *dev;
+	struct uclass *uc;
 	ulong now;
 
 	/* Exit if GD is not ready or watchdog is not initialized yet */
 	if (!gd || !(gd->flags & GD_FLG_WDT_READY))
 		return;
 
-	/* Do not reset the watchdog too often */
-	now = get_timer(0);
-	if (time_after_eq(now, next_reset)) {
-		next_reset = now + reset_period;
-		wdt_reset(gd->watchdog_dev);
+	if (uclass_get(UCLASS_WDT, &uc))
+		return;
+
+	/*
+	 * All devices bound to the wdt uclass should have been probed
+	 * in initr_watchdog(). But just in case something went wrong,
+	 * check device_active() before accessing the uclass private
+	 * data.
+	 */
+	uclass_foreach_dev(dev, uc) {
+		if (!device_active(dev))
+			continue;
+		priv = dev_get_uclass_priv(dev);
+		if (!priv->running)
+			continue;
+		/* Do not reset the watchdog too often */
+		now = get_timer(0);
+		if (time_after_eq(now, priv->next_reset)) {
+			priv->next_reset = now + priv->reset_period;
+			wdt_reset(dev);
+		}
 	}
 }
 #endif
@@ -179,9 +240,38 @@ static int wdt_post_bind(struct udevice *dev)
 	return 0;
 }
 
+static int wdt_pre_probe(struct udevice *dev)
+{
+	u32 timeout = WATCHDOG_TIMEOUT_SECS;
+	/*
+	 * Reset every 1000ms, or however often is required as
+	 * indicated by a hw_margin_ms property.
+	 */
+	ulong reset_period = 1000;
+	struct wdt_priv *priv;
+
+	if (CONFIG_IS_ENABLED(OF_CONTROL) && !CONFIG_IS_ENABLED(OF_PLATDATA)) {
+		timeout = dev_read_u32_default(dev, "timeout-sec", timeout);
+		reset_period = dev_read_u32_default(dev, "hw_margin_ms",
+						    4 * reset_period) / 4;
+	}
+	priv = dev_get_uclass_priv(dev);
+	priv->timeout = timeout;
+	priv->reset_period = reset_period;
+	/*
+	 * Pretend this device was last reset "long" ago so the first
+	 * watchdog_reset will actually call its ->reset method.
+	 */
+	priv->next_reset = get_timer(0);
+
+	return 0;
+}
+
 UCLASS_DRIVER(wdt) = {
-	.id		= UCLASS_WDT,
-	.name		= "watchdog",
-	.flags		= DM_UC_FLAG_SEQ_ALIAS,
-	.post_bind	= wdt_post_bind,
+	.id			= UCLASS_WDT,
+	.name			= "watchdog",
+	.flags			= DM_UC_FLAG_SEQ_ALIAS,
+	.post_bind		= wdt_post_bind,
+	.pre_probe		= wdt_pre_probe,
+	.per_device_auto	= sizeof(struct wdt_priv),
 };

include/asm-generic/global_data.h

@@ -447,12 +447,6 @@ struct global_data {
 	 */
 	fdt_addr_t translation_offset;
 #endif
-#if CONFIG_IS_ENABLED(WDT)
-	/**
-	 * @watchdog_dev: watchdog device
-	 */
-	struct udevice *watchdog_dev;
-#endif
 #ifdef CONFIG_GENERATE_ACPI_TABLE
 	/**
 	 * @acpi_ctx: ACPI context pointer

include/wdt.h

@@ -37,6 +37,14 @@ int wdt_start(struct udevice *dev, u64 timeout_ms, ulong flags);
  */
 int wdt_stop(struct udevice *dev);
 
+/*
+ * Stop all registered watchdog devices.
+ *
+ * @return: 0 if ok, first error encountered otherwise (but wdt_stop()
+ * is still called on following devices)
+ */
+int wdt_stop_all(void);
+
 /*
  * Reset the timer, typically restoring the counter to
  * the value configured by start()

test/dm/wdt.c

@@ -6,11 +6,14 @@
 #include <common.h>
 #include <dm.h>
 #include <wdt.h>
+#include <asm/gpio.h>
 #include <asm/state.h>
 #include <asm/test.h>
 #include <dm/test.h>
 #include <test/test.h>
 #include <test/ut.h>
+#include <linux/delay.h>
+#include <watchdog.h>
 
 /* Test that watchdog driver functions are called */
 static int dm_test_wdt_base(struct unit_test_state *uts)
@@ -19,7 +22,8 @@ static int dm_test_wdt_base(struct unit_test_state *uts)
 	struct udevice *dev;
 	const u64 timeout = 42;
 
-	ut_assertok(uclass_get_device(UCLASS_WDT, 0, &dev));
+	ut_assertok(uclass_get_device_by_driver(UCLASS_WDT,
+						DM_DRIVER_GET(wdt_sandbox), &dev));
 	ut_assertnonnull(dev);
 	ut_asserteq(0, state->wdt.counter);
 	ut_asserteq(false, state->wdt.running);
@@ -39,3 +43,87 @@ static int dm_test_wdt_base(struct unit_test_state *uts)
 	return 0;
 }
 DM_TEST(dm_test_wdt_base, UT_TESTF_SCAN_PDATA | UT_TESTF_SCAN_FDT);
+
+static int dm_test_wdt_gpio(struct unit_test_state *uts)
+{
+	/*
+	 * The sandbox wdt gpio is "connected" to gpio bank a, offset
+	 * 7. Use the sandbox back door to verify that the gpio-wdt
+	 * driver behaves as expected.
+	 */
+	struct udevice *wdt, *gpio;
+	const u64 timeout = 42;
+	const int offset = 7;
+	int val;
+
+	ut_assertok(uclass_get_device_by_driver(UCLASS_WDT,
+						DM_DRIVER_GET(wdt_gpio), &wdt));
+	ut_assertnonnull(wdt);
+
+	ut_assertok(uclass_get_device_by_name(UCLASS_GPIO, "base-gpios", &gpio));
+	ut_assertnonnull(gpio);
+	ut_assertok(wdt_start(wdt, timeout, 0));
+
+	val = sandbox_gpio_get_value(gpio, offset);
+	ut_assertok(wdt_reset(wdt));
+	ut_asserteq(!val, sandbox_gpio_get_value(gpio, offset));
+	ut_assertok(wdt_reset(wdt));
+	ut_asserteq(val, sandbox_gpio_get_value(gpio, offset));
+
+	ut_asserteq(-ENOSYS, wdt_stop(wdt));
+
+	return 0;
+}
+DM_TEST(dm_test_wdt_gpio, UT_TESTF_SCAN_FDT);
+
+static int dm_test_wdt_watchdog_reset(struct unit_test_state *uts)
+{
+	struct sandbox_state *state = state_get_current();
+	struct udevice *gpio_wdt, *sandbox_wdt;
+	struct udevice *gpio;
+	const u64 timeout = 42;
+	const int offset = 7;
+	uint reset_count;
+	int val;
+
+	ut_assertok(uclass_get_device_by_driver(UCLASS_WDT,
+						DM_DRIVER_GET(wdt_gpio), &gpio_wdt));
+	ut_assertnonnull(gpio_wdt);
+	ut_assertok(uclass_get_device_by_driver(UCLASS_WDT,
+						DM_DRIVER_GET(wdt_sandbox), &sandbox_wdt));
+	ut_assertnonnull(sandbox_wdt);
+	ut_assertok(uclass_get_device_by_name(UCLASS_GPIO, "base-gpios", &gpio));
+	ut_assertnonnull(gpio);
+
+	/* Neither device should be "started", so watchdog_reset() should be a no-op. */
+	reset_count = state->wdt.reset_count;
+	val = sandbox_gpio_get_value(gpio, offset);
+	watchdog_reset();
+	ut_asserteq(reset_count, state->wdt.reset_count);
+	ut_asserteq(val, sandbox_gpio_get_value(gpio, offset));
+
+	/* Start both devices. */
+	ut_assertok(wdt_start(gpio_wdt, timeout, 0));
+	ut_assertok(wdt_start(sandbox_wdt, timeout, 0));
+
+	/* Make sure both devices have just been pinged. */
+	timer_test_add_offset(100);
+	watchdog_reset();
+	reset_count = state->wdt.reset_count;
+	val = sandbox_gpio_get_value(gpio, offset);
+
+	/* The gpio watchdog should be pinged, the sandbox one not. */
+	timer_test_add_offset(30);
+	watchdog_reset();
+	ut_asserteq(reset_count, state->wdt.reset_count);
+	ut_asserteq(!val, sandbox_gpio_get_value(gpio, offset));
+
+	/* After another ~30ms, both devices should get pinged. */
+	timer_test_add_offset(30);
+	watchdog_reset();
+	ut_asserteq(reset_count + 1, state->wdt.reset_count);
+	ut_asserteq(val, sandbox_gpio_get_value(gpio, offset));
+
+	return 0;
+}
+DM_TEST(dm_test_wdt_watchdog_reset, UT_TESTF_SCAN_FDT);