[U-Boot] [PATCH v4 2/3] watchdog: orion_wdt: take timeout value in ms

[Chris Packham]

The generic wdt_start API expects to be called with the timeout in
milliseconds. Update the orion_wdt driver to accept a timeout in
milliseconds and use the clock rate specified in the dts to convert the
timeout to an appropriate value for the timer reload register.

Signed-off-by: Chris Packham <judge.packham at gmail.com>
---
It turned out to be easy enough to make orion_wdt conform to the
expected wdt APIs. It looks like the turris_mox already assumed a
timeout in ms, so only the turris_omnia needed updating.

Changes in v4:
- use DIV_ROUND_UP to avoid setting the timeout to 0.

Changes in v3:
- new

Changes in v2: None

 board/CZ.NIC/turris_omnia/turris_omnia.c |  2 +-
 drivers/watchdog/Kconfig                 |  1 +
 drivers/watchdog/orion_wdt.c             | 23 +++++++++++++++++++----
 3 files changed, 21 insertions(+), 5 deletions(-)

diff --git a/board/CZ.NIC/turris_omnia/turris_omnia.c b/board/CZ.NIC/turris_omnia/turris_omnia.c
index 1f7650cb3610..5e0b686c597d 100644
--- a/board/CZ.NIC/turris_omnia/turris_omnia.c
+++ b/board/CZ.NIC/turris_omnia/turris_omnia.c
@@ -379,7 +379,7 @@ int board_init(void)
 		puts("Cannot find Armada 385 watchdog!\n");
 	} else {
 		puts("Enabling Armada 385 watchdog.\n");
-		wdt_start(watchdog_dev, (u32) 25000000 * 120, 0);
+		wdt_start(watchdog_dev, 120000, 0);
 	}
 # endif
 
diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
index 115fc4551ffd..7f7bc4bbc494 100644
--- a/drivers/watchdog/Kconfig
+++ b/drivers/watchdog/Kconfig
@@ -97,6 +97,7 @@ config WDT_BCM6345
 config WDT_ORION
 	bool "Orion watchdog timer support"
 	depends on WDT
+	select CLK
 	help
 	   Select this to enable Orion watchdog timer, which can be found on some
 	   Marvell Armada chips.
diff --git a/drivers/watchdog/orion_wdt.c b/drivers/watchdog/orion_wdt.c
index c1add3e7c121..885821d562ea 100644
--- a/drivers/watchdog/orion_wdt.c
+++ b/drivers/watchdog/orion_wdt.c
@@ -14,7 +14,9 @@
 
 #include <common.h>
 #include <dm.h>
+#include <clk.h>
 #include <wdt.h>
+#include <linux/kernel.h>
 #include <asm/io.h>
 #include <asm/arch/cpu.h>
 #include <asm/arch/soc.h>
@@ -27,6 +29,8 @@ struct orion_wdt_priv {
 	void __iomem *rstout;
 	void __iomem *rstout_mask;
 	u32 timeout;
+	unsigned long clk_rate;
+	struct clk clk;
 };
 
 #define RSTOUT_ENABLE_BIT		BIT(8)
@@ -44,17 +48,18 @@ static int orion_wdt_reset(struct udevice *dev)
 	struct orion_wdt_priv *priv = dev_get_priv(dev);
 
 	/* Reload watchdog duration */
-	writel(priv->timeout, priv->reg + priv->wdt_counter_offset);
+	writel(priv->clk_rate * priv->timeout,
+	       priv->reg + priv->wdt_counter_offset);
 
 	return 0;
 }
 
-static int orion_wdt_start(struct udevice *dev, u64 timeout, ulong flags)
+static int orion_wdt_start(struct udevice *dev, u64 timeout_ms, ulong flags)
 {
 	struct orion_wdt_priv *priv = dev_get_priv(dev);
 	u32 reg;
 
-	priv->timeout = (u32) timeout;
+	priv->timeout = DIV_ROUND_UP(timeout_ms, 1000);
 
 	/* Enable the fixed watchdog clock input */
 	reg = readl(priv->reg + TIMER_CTRL);
@@ -62,7 +67,8 @@ static int orion_wdt_start(struct udevice *dev, u64 timeout, ulong flags)
 	writel(reg, priv->reg + TIMER_CTRL);
 
 	/* Set watchdog duration */
-	writel(priv->timeout, priv->reg + priv->wdt_counter_offset);
+	writel(priv->clk_rate * priv->timeout,
+	       priv->reg + priv->wdt_counter_offset);
 
 	/* Clear the watchdog expiration bit */
 	reg = readl(priv->reg + TIMER_A370_STATUS);
@@ -147,9 +153,18 @@ err:
 
 static int orion_wdt_probe(struct udevice *dev)
 {
+	struct orion_wdt_priv *priv = dev_get_priv(dev);
+	int ret;
+
 	debug("%s: Probing wdt%u\n", __func__, dev->seq);
 	orion_wdt_stop(dev);
 
+	ret = clk_get_by_name(dev, "fixed", &priv->clk);
+	if (!ret)
+		priv->clk_rate = clk_get_rate(&priv->clk);
+	else
+		priv->clk_rate = 25000000;
+
 	return 0;
 }
 
-- 
2.20.1