zynq: Add new ddrc driver for ECC support

The first 1MB is not initialized by first stage bootloader.
Check if memory is setup to 16bit mode and ECC is enabled.
If it is, clear the first 1MB.
Also u-boot should report only the half size of memory.

Acked-by: Jagannadha Sutradharudu Teki <jaganna@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>

1 files changed, 50 insertions, 0 deletions

diff --git a/arch/arm/cpu/armv7/zynq/ddrc.c b/arch/arm/cpu/armv7/zynq/ddrc.c
new file mode 100644
index 0000000000..ba6a6aee5c
--- /dev/null
+++ b/arch/arm/cpu/armv7/zynq/ddrc.c
@@ -0,0 +1,50 @@
+/*
+ * Copyright (C) 2012 - 2013 Michal Simek <monstr@monstr.eu>
+ * Copyright (C) 2012 - 2013 Xilinx, Inc. All rights reserved.
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <asm/io.h>
+#include <asm/arch/sys_proto.h>
+#include <asm/arch/hardware.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+/* Control regsiter bitfield definitions */
+#define ZYNQ_DDRC_CTRLREG_BUSWIDTH_MASK		0xC
+#define ZYNQ_DDRC_CTRLREG_BUSWIDTH_SHIFT	2
+#define ZYNQ_DDRC_CTRLREG_BUSWIDTH_16BIT	1
+
+/* ECC scrub regsiter definitions */
+#define ZYNQ_DDRC_ECC_SCRUBREG_ECC_MODE_MASK	0x7
+#define ZYNQ_DDRC_ECC_SCRUBREG_ECCMODE_SECDED	0x4
+
+void zynq_ddrc_init(void)
+{
+	u32 width, ecctype;
+
+	width = readl(&ddrc_base->ddrc_ctrl);
+	width = (width & ZYNQ_DDRC_CTRLREG_BUSWIDTH_MASK) >>
+					ZYNQ_DDRC_CTRLREG_BUSWIDTH_SHIFT;
+	ecctype = (readl(&ddrc_base->ecc_scrub) &
+		ZYNQ_DDRC_ECC_SCRUBREG_ECC_MODE_MASK);
+
+	/* ECC is enabled when memory is in 16bit mode and it is enabled */
+	if ((ecctype == ZYNQ_DDRC_ECC_SCRUBREG_ECCMODE_SECDED) &&
+	    (width == ZYNQ_DDRC_CTRLREG_BUSWIDTH_16BIT)) {
+		puts("Memory: ECC enabled\n");
+		/*
+		 * Clear the first 1MB because it is not initialized from
+		 * first stage bootloader. To get ECC to work all memory has
+		 * been initialized by writing any value.
+		 */
+		memset(0, 0, 1 * 1024 * 1024);
+	} else {
+		puts("Memory: ECC disabled\n");
+	}
+
+	if (width == ZYNQ_DDRC_CTRLREG_BUSWIDTH_16BIT)
+		gd->ram_size /= 2;
+}