From 043bc98c4b236916c7357ef815c7ab6c2bea38c5 Mon Sep 17 00:00:00 2001 From: Sascha Hauer Date: Mon, 16 Jan 2017 11:40:36 +0100 Subject: watchdog: i.MX: Fix internal/external reset The watchdog can either reset only the SoC or assert the WDOG_B output signal instead. On some boards it's necessary to use the external WDOG_B output to make sure that external devices like the PMIC are also properly resetted. This has been fixed in the Linux driver which honours a fsl,ext-reset-output device tree property to select between both ways. Do the same in the barebox driver. Signed-off-by: Sascha Hauer --- drivers/watchdog/imxwd.c | 16 ++++++++++++++-- 1 file changed, 14 insertions(+), 2 deletions(-) diff --git a/drivers/watchdog/imxwd.c b/drivers/watchdog/imxwd.c index d1b98e62ef..b920c7234b 100644 --- a/drivers/watchdog/imxwd.c +++ b/drivers/watchdog/imxwd.c @@ -36,6 +36,7 @@ struct imx_wd { struct device_d *dev; const struct imx_wd_ops *ops; struct restart_handler restart; + bool ext_reset; }; #define to_imx_wd(h) container_of(h, struct imx_wd, wd) @@ -51,6 +52,7 @@ struct imx_wd { #define IMX21_WDOG_WSTR 0x04 /* Watchdog Status Register */ #define IMX21_WDOG_WMCR 0x08 /* Misc Register */ #define IMX21_WDOG_WCR_WDE (1 << 2) +#define IMX21_WDOG_WCR_WDT (1 << 3) #define IMX21_WDOG_WCR_SRS (1 << 4) #define IMX21_WDOG_WCR_WDA (1 << 5) @@ -109,6 +111,9 @@ static int imx21_watchdog_set_timeout(struct imx_wd *priv, unsigned timeout) val = ((timeout * 2 - 1) << 8) | IMX21_WDOG_WCR_SRS | IMX21_WDOG_WCR_WDA; + if (priv->ext_reset) + val |= IMX21_WDOG_WCR_WDT; + writew(IMX21_WDOG_WCR_WDE | val, priv->base + IMX21_WDOG_WCR); /* Write Service Sequence */ @@ -120,9 +125,13 @@ static int imx21_watchdog_set_timeout(struct imx_wd *priv, unsigned timeout) static void imx21_soc_reset(struct imx_wd *priv) { - u16 val; + u16 val = 0; - val = IMX21_WDOG_WCR_SRS | IMX21_WDOG_WCR_WDA; + /* Use internal reset or external - not both */ + if (priv->ext_reset) + val |= IMX21_WDOG_WCR_SRS; /* do not assert int reset */ + else + val |= IMX21_WDOG_WCR_WDA; /* do not assert ext-reset */ writew(val, priv->base + IMX21_WDOG_WCR); } @@ -202,6 +211,9 @@ static int imx_wd_probe(struct device_d *dev) priv->wd.dev = dev; priv->dev = dev; + priv->ext_reset = of_property_read_bool(dev->device_node, + "fsl,ext-reset-output"); + if (IS_ENABLED(CONFIG_WATCHDOG_IMX)) { ret = watchdog_register(&priv->wd); if (ret) -- cgit v1.2.3