watchdog: imx: Add DM support

Add DM and DT probing support to iMX watchdog driver. This should
allow boards to move over to this driver, enable SYSRESET_WATCHDOG
to handle cpu_reset() if required.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Peng Fan <Peng.Fan@freescale.com>
Cc: Stefano Babic <sbabic@denx.de>
Tested-by: Heiko Schocher <hs@denx.de>

diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
index de9bd87236b6d9213ca9e6b3f63e6b933290acb9..ccda432f49ab27a408bd27386d7ca52a1fc1328e 100644 (file)
--- a/drivers/watchdog/Kconfig
+++ b/drivers/watchdog/Kconfig
@@ -28,7 +28,7 @@ config BCM2835_WDT
 
 config IMX_WATCHDOG
        bool "Enable Watchdog Timer support for IMX and LSCH2 of NXP"
-       select HW_WATCHDOG
+       select HW_WATCHDOG if !WDT
        help
           Select this to enable the IMX and LSCH2 of Layerscape watchdog
           driver.

diff --git a/drivers/watchdog/imx_watchdog.c b/drivers/watchdog/imx_watchdog.c
index 14cc618074bd84f312b502c16cc01389d8095b42..53a3e9f5c78e8a794c7098468973bafb78ec02f9 100644 (file)
--- a/drivers/watchdog/imx_watchdog.c
+++ b/drivers/watchdog/imx_watchdog.c
@@ -5,7 +5,9 @@
  */
 
 #include <common.h>
+#include <dm.h>
 #include <asm/io.h>
+#include <wdt.h>
 #include <watchdog.h>
 #include <asm/arch/imx-regs.h>
 #ifdef CONFIG_FSL_LSCH2
@@ -13,20 +15,40 @@
 #endif
 #include <fsl_wdog.h>
 
-#ifdef CONFIG_IMX_WATCHDOG
-void hw_watchdog_reset(void)
+static void imx_watchdog_expire_now(struct watchdog_regs *wdog)
+{
+       clrsetbits_le16(&wdog->wcr, WCR_WT_MSK, WCR_WDE);
+
+       writew(0x5555, &wdog->wsr);
+       writew(0xaaaa, &wdog->wsr);     /* load minimum 1/2 second timeout */
+       while (1) {
+               /*
+                * spin for .5 seconds before reset
+                */
+       }
+}
+
+#if !defined(CONFIG_IMX_WATCHDOG) || \
+    (defined(CONFIG_IMX_WATCHDOG) && !CONFIG_IS_ENABLED(WDT))
+void __attribute__((weak)) reset_cpu(ulong addr)
 {
-#ifndef CONFIG_WATCHDOG_RESET_DISABLE
        struct watchdog_regs *wdog = (struct watchdog_regs *)WDOG1_BASE_ADDR;
 
+       imx_watchdog_expire_now(wdog);
+}
+#endif
+
+#if defined(CONFIG_IMX_WATCHDOG)
+static void imx_watchdog_reset(struct watchdog_regs *wdog)
+{
+#ifndef CONFIG_WATCHDOG_RESET_DISABLE
        writew(0x5555, &wdog->wsr);
        writew(0xaaaa, &wdog->wsr);
 #endif /* CONFIG_WATCHDOG_RESET_DISABLE*/
 }
 
-void hw_watchdog_init(void)
+static void imx_watchdog_init(struct watchdog_regs *wdog)
 {
-       struct watchdog_regs *wdog = (struct watchdog_regs *)WDOG1_BASE_ADDR;
        u16 timeout;
 
        /*
@@ -44,21 +66,86 @@ void hw_watchdog_init(void)
        writew(WCR_WDZST | WCR_WDBG | WCR_WDE | WCR_WDT | WCR_SRS |
                WCR_WDA | SET_WCR_WT(timeout), &wdog->wcr);
 #endif /* CONFIG_FSL_LSCH2*/
-       hw_watchdog_reset();
+       imx_watchdog_reset(wdog);
 }
-#endif
 
-void __attribute__((weak)) reset_cpu(ulong addr)
+#if !CONFIG_IS_ENABLED(WDT)
+void hw_watchdog_reset(void)
 {
        struct watchdog_regs *wdog = (struct watchdog_regs *)WDOG1_BASE_ADDR;
 
-       clrsetbits_le16(&wdog->wcr, WCR_WT_MSK, WCR_WDE);
+       imx_watchdog_reset(wdog);
+}
 
-       writew(0x5555, &wdog->wsr);
-       writew(0xaaaa, &wdog->wsr);     /* load minimum 1/2 second timeout */
-       while (1) {
-               /*
-                * spin for .5 seconds before reset
-                */
-       }
+void hw_watchdog_init(void)
+{
+       struct watchdog_regs *wdog = (struct watchdog_regs *)WDOG1_BASE_ADDR;
+
+       imx_watchdog_init(wdog);
+}
+#else
+struct imx_wdt_priv {
+       void __iomem *base;
+};
+
+static int imx_wdt_reset(struct udevice *dev)
+{
+       struct imx_wdt_priv *priv = dev_get_priv(dev);
+
+       imx_watchdog_reset(priv->base);
+
+       return 0;
+}
+
+static int imx_wdt_expire_now(struct udevice *dev, ulong flags)
+{
+       struct imx_wdt_priv *priv = dev_get_priv(dev);
+
+       imx_watchdog_expire_now(priv->base);
+       hang();
+
+       return 0;
+}
+
+static int imx_wdt_start(struct udevice *dev, u64 timeout, ulong flags)
+{
+       struct imx_wdt_priv *priv = dev_get_priv(dev);
+
+       imx_watchdog_init(priv->base);
+
+       return 0;
+}
+
+static int imx_wdt_probe(struct udevice *dev)
+{
+       struct imx_wdt_priv *priv = dev_get_priv(dev);
+
+       priv->base = dev_read_addr_ptr(dev);
+       if (!priv->base)
+               return -ENOENT;
+
+       return 0;
 }
+
+static const struct wdt_ops imx_wdt_ops = {
+       .start          = imx_wdt_start,
+       .reset          = imx_wdt_reset,
+       .expire_now     = imx_wdt_expire_now,
+};
+
+static const struct udevice_id imx_wdt_ids[] = {
+       { .compatible = "fsl,imx21-wdt" },
+       {}
+};
+
+U_BOOT_DRIVER(imx_wdt) = {
+       .name           = "imx_wdt",
+       .id             = UCLASS_WDT,
+       .of_match       = imx_wdt_ids,
+       .probe          = imx_wdt_probe,
+       .ops            = &imx_wdt_ops,
+       .priv_auto_alloc_size = sizeof(struct imx_wdt_priv),
+       .flags          = DM_FLAG_PRE_RELOC,
+};
+#endif
+#endif