arm: ls102xa: clear EPU registers for deep sleep

After wakeup from deep sleep, Clear EPU registers as early as possible
to prevent from possible issue. It's also safe to clear at normal boot.

Signed-off-by: Chenhui Zhao <chenhui.zhao@freescale.com>
Reviewed-by: York Sun <yorksun@freescale.com>

4 files changed, 142 insertions, 0 deletions

diff --git a/arch/arm/cpu/armv7/ls102xa/Makefile b/arch/arm/cpu/armv7/ls102xa/Makefile
index d82ce8d..ae4f25d 100644
--- a/arch/arm/cpu/armv7/ls102xa/Makefile
+++ b/arch/arm/cpu/armv7/ls102xa/Makefile
@@ -7,6 +7,7 @@
 obj-y	+= cpu.o
 obj-y	+= clock.o
 obj-y	+= timer.o
+obj-y	+= fsl_epu.o
 
 obj-$(CONFIG_OF_LIBFDT) += fdt.o
 obj-$(CONFIG_SYS_HAS_SERDES) += fsl_ls1_serdes.o ls102xa_serdes.o
diff --git a/arch/arm/cpu/armv7/ls102xa/cpu.c b/arch/arm/cpu/armv7/ls102xa/cpu.c
index b7dde45..fae6c68 100644
--- a/arch/arm/cpu/armv7/ls102xa/cpu.c
+++ b/arch/arm/cpu/armv7/ls102xa/cpu.c
@@ -12,6 +12,8 @@
 #include <netdev.h>
 #include <fsl_esdhc.h>
 
+#include "fsl_epu.h"
+
 DECLARE_GLOBAL_DATA_PTR;
 
 #if defined(CONFIG_DISPLAY_CPUINFO)
@@ -101,3 +103,17 @@ int cpu_eth_init(bd_t *bis)
 
 	return 0;
 }
+
+int arch_cpu_init(void)
+{
+	void *epu_base = (void *)(CONFIG_SYS_DCSRBAR + EPU_BLOCK_OFFSET);
+
+	/*
+	 * After wakeup from deep sleep, Clear EPU registers
+	 * as early as possible to prevent from possible issue.
+	 * It's also safe to clear at normal boot.
+	 */
+	fsl_epu_clean(epu_base);
+
+	return 0;
+}
diff --git a/arch/arm/cpu/armv7/ls102xa/fsl_epu.c b/arch/arm/cpu/armv7/ls102xa/fsl_epu.c
new file mode 100644
index 0000000..6212640
--- /dev/null
+++ b/arch/arm/cpu/armv7/ls102xa/fsl_epu.c
@@ -0,0 +1,57 @@
+/*
+ * Copyright 2014 Freescale Semiconductor, Inc.
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <asm/io.h>
+
+#include "fsl_epu.h"
+
+/**
+ * fsl_epu_clean - Clear EPU registers
+ */
+void fsl_epu_clean(void *epu_base)
+{
+	u32 offset;
+
+	/* follow the exact sequence to clear the registers */
+	/* Clear EPACRn */
+	for (offset = EPACR0; offset <= EPACR15; offset += EPACR_STRIDE)
+		out_be32(epu_base + offset, 0);
+
+	/* Clear EPEVTCRn */
+	for (offset = EPEVTCR0; offset <= EPEVTCR9; offset += EPEVTCR_STRIDE)
+		out_be32(epu_base + offset, 0);
+
+	/* Clear EPGCR */
+	out_be32(epu_base + EPGCR, 0);
+
+	/* Clear EPSMCRn */
+	for (offset = EPSMCR0; offset <= EPSMCR15; offset += EPSMCR_STRIDE)
+		out_be32(epu_base + offset, 0);
+
+	/* Clear EPCCRn */
+	for (offset = EPCCR0; offset <= EPCCR31; offset += EPCCR_STRIDE)
+		out_be32(epu_base + offset, 0);
+
+	/* Clear EPCMPRn */
+	for (offset = EPCMPR0; offset <= EPCMPR31; offset += EPCMPR_STRIDE)
+		out_be32(epu_base + offset, 0);
+
+	/* Clear EPCTRn */
+	for (offset = EPCTR0; offset <= EPCTR31; offset += EPCTR_STRIDE)
+		out_be32(epu_base + offset, 0);
+
+	/* Clear EPIMCRn */
+	for (offset = EPIMCR0; offset <= EPIMCR31; offset += EPIMCR_STRIDE)
+		out_be32(epu_base + offset, 0);
+
+	/* Clear EPXTRIGCRn */
+	out_be32(epu_base + EPXTRIGCR, 0);
+
+	/* Clear EPECRn */
+	for (offset = EPECR0; offset <= EPECR15; offset += EPECR_STRIDE)
+		out_be32(epu_base + offset, 0);
+}
diff --git a/arch/arm/cpu/armv7/ls102xa/fsl_epu.h b/arch/arm/cpu/armv7/ls102xa/fsl_epu.h
new file mode 100644
index 0000000..d658aad
--- /dev/null
+++ b/arch/arm/cpu/armv7/ls102xa/fsl_epu.h
@@ -0,0 +1,68 @@
+/*
+ * Copyright 2014 Freescale Semiconductor, Inc.
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#ifndef __FSL_EPU_H
+#define __FSL_EPU_H
+
+#include <asm/types.h>
+
+#define FSL_STRIDE_4B	4
+#define FSL_STRIDE_8B	8
+
+/* Block offsets */
+#define EPU_BLOCK_OFFSET	0x00000000
+
+/* EPGCR (Event Processor Global Control Register) */
+#define EPGCR		0x000
+
+/* EPEVTCR0-9 (Event Processor EVT Pin Control Registers) */
+#define EPEVTCR0	0x050
+#define EPEVTCR9	0x074
+#define EPEVTCR_STRIDE	FSL_STRIDE_4B
+
+/* EPXTRIGCR (Event Processor Crosstrigger Control Register) */
+#define EPXTRIGCR	0x090
+
+/* EPIMCR0-31 (Event Processor Input Mux Control Registers) */
+#define EPIMCR0		0x100
+#define EPIMCR31	0x17C
+#define EPIMCR_STRIDE	FSL_STRIDE_4B
+
+/* EPSMCR0-15 (Event Processor SCU Mux Control Registers) */
+#define EPSMCR0		0x200
+#define EPSMCR15	0x278
+#define EPSMCR_STRIDE	FSL_STRIDE_8B
+
+/* EPECR0-15 (Event Processor Event Control Registers) */
+#define EPECR0		0x300
+#define EPECR15		0x33C
+#define EPECR_STRIDE	FSL_STRIDE_4B
+
+/* EPACR0-15 (Event Processor Action Control Registers) */
+#define EPACR0		0x400
+#define EPACR15		0x43C
+#define EPACR_STRIDE	FSL_STRIDE_4B
+
+/* EPCCRi0-15 (Event Processor Counter Control Registers) */
+#define EPCCR0		0x800
+#define EPCCR15		0x83C
+#define EPCCR31		0x87C
+#define EPCCR_STRIDE	FSL_STRIDE_4B
+
+/* EPCMPR0-15 (Event Processor Counter Compare Registers) */
+#define EPCMPR0		0x900
+#define EPCMPR15	0x93C
+#define EPCMPR31	0x97C
+#define EPCMPR_STRIDE	FSL_STRIDE_4B
+
+/* EPCTR0-31 (Event Processor Counter Register) */
+#define EPCTR0		0xA00
+#define EPCTR31		0xA7C
+#define EPCTR_STRIDE	FSL_STRIDE_4B
+
+void fsl_epu_clean(void *epu_base);
+
+#endif