watchdog: driver support for fsl-lsch2

Support watchdog driver for fsl-lsch2. It's disabled in default.
If you want to use it, please enable CONFIG_IMX_WATCHDOG.
Define CONFIG_WATCHDOG_TIMEOUT_MSECS to set watchdog timeout.

Signed-off-by: Xiaoliang Yang <xiaoliang.yang_1@nxp.com>
diff --git a/arch/arm/cpu/armv8/fsl-layerscape/doc/README.lsch2 b/arch/arm/cpu/armv8/fsl-layerscape/doc/README.lsch2
index a6ef830..9176546 100644
--- a/arch/arm/cpu/armv8/fsl-layerscape/doc/README.lsch2
+++ b/arch/arm/cpu/armv8/fsl-layerscape/doc/README.lsch2
@@ -8,3 +8,12 @@
 
 This architecture supports Freescale ARMv8 SoCs with Chassis generation 2,
 for example LS1043A.
+
+Watchdog support Overview
+-------------------
+Support watchdog driver for LSCH2. The driver is disabled in default.
+You can enable it by setting CONFIG_IMX_WATCHDOG.
+Use following config to set watchdog timeout, if this config is not defined,
+the default timeout value is 128s which is the maximum. Set 10 seconds for
+example:
+    #define CONFIG_WATCHDOG_TIMEOUT_MSECS 10000
diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
index 74738ee..d901240 100644
--- a/drivers/watchdog/Makefile
+++ b/drivers/watchdog/Makefile
@@ -7,6 +7,8 @@
 obj-$(CONFIG_FTWDT010_WATCHDOG) += ftwdt010_wdt.o
 ifneq (,$(filter $(SOC), mx25 mx31 mx35 mx5 mx6 mx7 vf610))
 obj-y += imx_watchdog.o
+else
+obj-$(CONFIG_IMX_WATCHDOG) += imx_watchdog.o
 endif
 obj-$(CONFIG_S5P)               += s5p_wdt.o
 obj-$(CONFIG_XILINX_TB_WATCHDOG) += xilinx_tb_wdt.o
diff --git a/drivers/watchdog/imx_watchdog.c b/drivers/watchdog/imx_watchdog.c
index 3f826d1..ddcf474 100644
--- a/drivers/watchdog/imx_watchdog.c
+++ b/drivers/watchdog/imx_watchdog.c
@@ -8,6 +8,9 @@
 #include <asm/io.h>
 #include <watchdog.h>
 #include <asm/arch/imx-regs.h>
+#ifdef CONFIG_FSL_LSCH2
+#include <asm/arch/immap_lsch2.h>
+#endif
 #include <fsl_wdog.h>
 
 #ifdef CONFIG_IMX_WATCHDOG
@@ -33,8 +36,12 @@
 #define CONFIG_WATCHDOG_TIMEOUT_MSECS 128000
 #endif
 	timeout = (CONFIG_WATCHDOG_TIMEOUT_MSECS / 500) - 1;
+#ifdef CONFIG_FSL_LSCH2
+	writew((WCR_WDA | WCR_SRS | WCR_WDE) << 8 | timeout, &wdog->wcr);
+#else
 	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();
 }
 #endif