armv8/ls2080a: configure PMU's PCTBENR to enable WDT

The SP805-WDT module on LS2080A requires configuration of PMU's
PCTBENR register to enable watchdog counter decrement and reset
signal generation. The watchdog clock needs to be enabled first.

Signed-off-by: Yunhui Cui <yunhui.cui@nxp.com>
Reviewed-by: York Sun <york.sun@nxp.com>
diff --git a/arch/arm/cpu/armv8/fsl-layerscape/cpu.c b/arch/arm/cpu/armv8/fsl-layerscape/cpu.c
index 9a5a6b5..297687d 100644
--- a/arch/arm/cpu/armv8/fsl-layerscape/cpu.c
+++ b/arch/arm/cpu/armv8/fsl-layerscape/cpu.c
@@ -636,6 +636,9 @@
 #ifdef CONFIG_FSL_LSCH3
 	u32 __iomem *cltbenr = (u32 *)CONFIG_SYS_FSL_PMU_CLTBENR;
 #endif
+#ifdef CONFIG_LS2080A
+	u32 __iomem *pctbenr = (u32 *)FSL_PMU_PCTBENR_OFFSET;
+#endif
 #ifdef COUNTER_FREQUENCY_REAL
 	unsigned long cntfrq = COUNTER_FREQUENCY_REAL;
 
@@ -650,6 +653,15 @@
 	out_le32(cltbenr, 0xf);
 #endif
 
+#ifdef CONFIG_LS2080A
+	/*
+	 * In certain Layerscape SoCs, the clock for each core's
+	 * has an enable bit in the PMU Physical Core Time Base Enable
+	 * Register (PCTBENR), which allows the watchdog to operate.
+	 */
+	setbits_le32(pctbenr, 0xff);
+#endif
+
 	/* Enable clock for timer
 	 * This is a global setting.
 	 */
diff --git a/arch/arm/include/asm/arch-fsl-layerscape/immap_lsch3.h b/arch/arm/include/asm/arch-fsl-layerscape/immap_lsch3.h
index 65b3357..c6b9f13 100644
--- a/arch/arm/include/asm/arch-fsl-layerscape/immap_lsch3.h
+++ b/arch/arm/include/asm/arch-fsl-layerscape/immap_lsch3.h
@@ -26,6 +26,7 @@
 #define CONFIG_SYS_FSL_TIMER_ADDR		0x023d0000
 #define CONFIG_SYS_FSL_PMU_CLTBENR		(CONFIG_SYS_FSL_PMU_ADDR + \
 						 0x18A0)
+#define FSL_PMU_PCTBENR_OFFSET (CONFIG_SYS_FSL_PMU_ADDR + 0x8A0)
 
 #define CONFIG_SYS_FSL_WRIOP1_ADDR		(CONFIG_SYS_IMMR + 0x7B80000)
 #define CONFIG_SYS_FSL_WRIOP1_MDIO1	(CONFIG_SYS_FSL_WRIOP1_ADDR + 0x16000)