arm: at91/spl: mpddrc: add mpddrc DDR3-SDRAM initialization

The DDR3-SDRAM initialization sequence is implemented in
accordance with the DDR3-SRAM/DDR3L-SDRAM initialization section
described in the SAMA5D2 datasheet.

Add registers and definitions of mpddrc controller, which is used
to support DDR3 devices.

Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>
Reviewed-by: Andreas Bießmann <andreas.devel@googlemail.com>
diff --git a/arch/arm/mach-at91/include/mach/atmel_mpddrc.h b/arch/arm/mach-at91/include/mach/atmel_mpddrc.h
index 47b4cd4..d37d908 100644
--- a/arch/arm/mach-at91/include/mach/atmel_mpddrc.h
+++ b/arch/arm/mach-at91/include/mach/atmel_mpddrc.h
@@ -2,6 +2,9 @@
  * Copyright (C) 2013 Atmel Corporation
  *		      Bo Shen <voice.shen@atmel.com>
  *
+ * Copyright (C) 2015 Atmel Corporation
+ *		      Wenyou Yang <wenyou.yang@atmel.com>
+ *
  * SPDX-License-Identifier:	GPL-2.0+
  */
 
@@ -23,14 +26,35 @@
  * If other register needed, will add them later
  */
 struct atmel_mpddr {
-	u32 mr;
-	u32 rtr;
-	u32 cr;
-	u32 tpr0;
-	u32 tpr1;
-	u32 tpr2;
-	u32 reserved[2];
-	u32 md;
+	u32 mr;			/* 0x00: Mode Register */
+	u32 rtr;		/* 0x04: Refresh Timer Register */
+	u32 cr;			/* 0x08: Configuration Register */
+	u32 tpr0;		/* 0x0c: Timing Parameter 0 Register */
+	u32 tpr1;		/* 0x10: Timing Parameter 1 Register */
+	u32 tpr2;		/* 0x14: Timing Parameter 2 Register */
+	u32 reserved;		/* 0x18: Reserved */
+	u32 lpr;		/* 0x1c: Low-power Register */
+	u32 md;			/* 0x20: Memory Device Register */
+	u32 reserved1;		/* 0x24: Reserved */
+	u32 lpddr23_lpr;	/* 0x28: LPDDR2-LPDDR3 Low-power Register*/
+	u32 cal_mr4;		/* 0x2c: Calibration and MR4 Register */
+	u32 tim_cal;		/* 0x30: Timing Calibration Register */
+	u32 io_calibr;		/* 0x34: IO Calibration */
+	u32 ocms;		/* 0x38: OCMS Register */
+	u32 ocms_key1;		/* 0x3c: OCMS KEY1 Register */
+	u32 ocms_key2;		/* 0x40: OCMS KEY2 Register */
+	u32 conf_arbiter;	/* 0x44: Configuration Arbiter Register */
+	u32 timeout;		/* 0x48: Timeout Port 0/1/2/3 Register */
+	u32 req_port0123;	/* 0x4c: Request Port 0/1/2/3 Register */
+	u32 req_port4567;	/* 0x50: Request Port 4/5/6/7 Register */
+	u32 bdw_port0123;	/* 0x54: Bandwidth Port 0/1/2/3 Register */
+	u32 bdw_port4567;	/* 0x58: Bandwidth Port 4/5/6/7 Register */
+	u32 rd_data_path;	/* 0x5c: Read Datapath Register */
+	u32 reserved2[33];
+	u32 wpmr;		/* 0xe4: Write Protection Mode Register */
+	u32 wpsr;		/* 0xe8: Write Protection Status Register */
+	u32 reserved3[4];
+	u32 version;		/* 0xfc: IP version */
 };
 
 
@@ -38,6 +62,10 @@
 	      const unsigned int ram_address,
 	      const struct atmel_mpddrc_config *mpddr_value);
 
+int ddr3_init(const unsigned int base,
+	      const unsigned int ram_address,
+	      const struct atmel_mpddrc_config *mpddr_value);
+
 /* Bit field in mode register */
 #define ATMEL_MPDDRC_MR_MODE_NORMAL_CMD		0x0
 #define ATMEL_MPDDRC_MR_MODE_NOP_CMD		0x1
@@ -120,9 +148,51 @@
 
 /* Bit field in Memory Device Register */
 #define ATMEL_MPDDRC_MD_LPDDR_SDRAM	0x3
+#define ATMEL_MPDDRC_MD_DDR3_SDRAM	0x4
+#define ATMEL_MPDDRC_MD_LPDDR3_SDRAM	0x5
 #define ATMEL_MPDDRC_MD_DDR2_SDRAM	0x6
 #define ATMEL_MPDDRC_MD_DBW_MASK	(0x1 << 4)
 #define ATMEL_MPDDRC_MD_DBW_32_BITS	(0x0 << 4)
 #define ATMEL_MPDDRC_MD_DBW_16_BITS	(0x1 << 4)
 
+/* Bit field in I/O Calibration Register */
+#define ATMEL_MPDDRC_IO_CALIBR_RDIV		0x7
+
+#define ATMEL_MPDDRC_IO_CALIBR_LPDDR2_RZQ_34_3	0x1
+#define ATMEL_MPDDRC_IO_CALIBR_LPDDR2_RZQ_40	0x2
+#define ATMEL_MPDDRC_IO_CALIBR_LPDDR2_RZQ_48	0x3
+#define ATMEL_MPDDRC_IO_CALIBR_LPDDR2_RZQ_60	0x4
+#define ATMEL_MPDDRC_IO_CALIBR_LPDDR2_RZQ_80	0x6
+#define ATMEL_MPDDRC_IO_CALIBR_LPDDR2_RZQ_120	0x7
+
+#define ATMEL_MPDDRC_IO_CALIBR_DDR2_RZQ_35	0x2
+#define ATMEL_MPDDRC_IO_CALIBR_DDR2_RZQ_43	0x3
+#define ATMEL_MPDDRC_IO_CALIBR_DDR2_RZQ_52	0x4
+#define ATMEL_MPDDRC_IO_CALIBR_DDR2_RZQ_70	0x6
+#define ATMEL_MPDDRC_IO_CALIBR_DDR2_RZQ_105	0x7
+
+#define ATMEL_MPDDRC_IO_CALIBR_DDR3_RZQ_37	0x2
+#define ATMEL_MPDDRC_IO_CALIBR_DDR3_RZQ_44	0x3
+#define ATMEL_MPDDRC_IO_CALIBR_DDR3_RZQ_55	0x4
+#define ATMEL_MPDDRC_IO_CALIBR_DDR3_RZQ_73	0x6
+#define ATMEL_MPDDRC_IO_CALIBR_DDR3_RZQ_110	0x7
+
+#define ATMEL_MPDDRC_IO_CALIBR_DDR3_RZQ_37	0x2
+#define ATMEL_MPDDRC_IO_CALIBR_DDR3_RZQ_44	0x3
+#define ATMEL_MPDDRC_IO_CALIBR_DDR3_RZQ_55	0x4
+#define ATMEL_MPDDRC_IO_CALIBR_DDR3_RZQ_73	0x6
+#define ATMEL_MPDDRC_IO_CALIBR_DDR3_RZQ_110	0x7
+
+#define ATMEL_MPDDRC_IO_CALIBR_TZQIO		0x7f
+#define ATMEL_MPDDRC_IO_CALIBR_TZQIO_(x)	(((x) & 0x7f) << 8)
+
+#define ATMEL_MPDDRC_IO_CALIBR_EN_CALIB		(0x1 << 4)
+
+/* Bit field in Read Data Path Register */
+#define ATMEL_MPDDRC_RD_DATA_PATH_SHIFT_SAMPLING	0x3
+#define ATMEL_MPDDRC_RD_DATA_PATH_NO_SHIFT		0x0
+#define ATMEL_MPDDRC_RD_DATA_PATH_SHIFT_ONE_CYCLE	0x1
+#define ATMEL_MPDDRC_RD_DATA_PATH_SHIFT_TWO_CYCLE	0x2
+#define ATMEL_MPDDRC_RD_DATA_PATH_SHIFT_THREE_CYCLE	0x3
+
 #endif
diff --git a/arch/arm/mach-at91/mpddrc.c b/arch/arm/mach-at91/mpddrc.c
index 9ba2a00..1e1ff1d 100644
--- a/arch/arm/mach-at91/mpddrc.c
+++ b/arch/arm/mach-at91/mpddrc.c
@@ -2,6 +2,9 @@
  * Copyright (C) 2013 Atmel Corporation
  *		      Bo Shen <voice.shen@atmel.com>
  *
+ * Copyright (C) 2015 Atmel Corporation
+ *		      Wenyou Yang <wenyou.yang@atmel.com>
+ *
  * SPDX-License-Identifier:	GPL-2.0+
  */
 
@@ -135,3 +138,89 @@
 
 	return 0;
 }
+
+int ddr3_init(const unsigned int base,
+	      const unsigned int ram_address,
+	      const struct atmel_mpddrc_config *mpddr_value)
+{
+	struct atmel_mpddr *mpddr = (struct atmel_mpddr *)base;
+	u32 ba_off;
+
+	/* Compute bank offset according to NC in configuration register */
+	ba_off = (mpddr_value->cr & ATMEL_MPDDRC_CR_NC_MASK) + 9;
+	if (ddr2_decodtype_is_seq(mpddr_value->cr))
+		ba_off += ((mpddr_value->cr &
+			   ATMEL_MPDDRC_CR_NR_MASK) >> 2) + 11;
+
+	ba_off += (mpddr_value->md & ATMEL_MPDDRC_MD_DBW_MASK) ? 1 : 2;
+
+	/* Program the memory device type */
+	writel(mpddr_value->md, &mpddr->md);
+
+	/*
+	 * Program features of the DDR3-SDRAM device and timing parameters
+	 */
+	writel(mpddr_value->cr, &mpddr->cr);
+
+	writel(mpddr_value->tpr0, &mpddr->tpr0);
+	writel(mpddr_value->tpr1, &mpddr->tpr1);
+	writel(mpddr_value->tpr2, &mpddr->tpr2);
+
+	/* A NOP command is issued to the DDR3-SRAM */
+	atmel_mpddr_op(mpddr, ATMEL_MPDDRC_MR_MODE_NOP_CMD, ram_address);
+
+	/* A pause of at least 500us must be observed before a single toggle. */
+	udelay(500);
+
+	/* A NOP command is issued to the DDR3-SDRAM */
+	atmel_mpddr_op(mpddr, ATMEL_MPDDRC_MR_MODE_NOP_CMD, ram_address);
+
+	/*
+	 * An Extended Mode Register Set (EMRS2) cycle is issued to choose
+	 * between commercial or high temperature operations.
+	 */
+	atmel_mpddr_op(mpddr, ATMEL_MPDDRC_MR_MODE_EXT_LMR_CMD,
+		       ram_address + (0x2 << ba_off));
+	/*
+	 * Step 7: An Extended Mode Register Set (EMRS3) cycle is issued to set
+	 * the Extended Mode Register to 0.
+	 */
+	atmel_mpddr_op(mpddr, ATMEL_MPDDRC_MR_MODE_EXT_LMR_CMD,
+		       ram_address + (0x3 << ba_off));
+	/*
+	 * An Extended Mode Register Set (EMRS1) cycle is issued to disable and
+	 * to program O.D.S. (Output Driver Strength).
+	 */
+	atmel_mpddr_op(mpddr, ATMEL_MPDDRC_MR_MODE_EXT_LMR_CMD,
+		       ram_address + (0x1 << ba_off));
+
+	/*
+	 * Write a one to the DLL bit (enable DLL reset) in the MPDDRC
+	 * Configuration Register.
+	 */
+
+	/* A Mode Register Set (MRS) cycle is issued to reset DLL. */
+	atmel_mpddr_op(mpddr, ATMEL_MPDDRC_MR_MODE_LMR_CMD, ram_address);
+
+	udelay(50);
+
+	/*
+	 * A Calibration command (MRS) is issued to calibrate RTT and RON
+	 * values for the Process Voltage Temperature (PVT).
+	 */
+	atmel_mpddr_op(mpddr, ATMEL_MPDDRC_MR_MODE_DEEP_CMD, ram_address);
+
+	/* A Normal Mode command is provided. */
+	atmel_mpddr_op(mpddr, ATMEL_MPDDRC_MR_MODE_NORMAL_CMD, ram_address);
+
+	/* Perform a write access to any DDR3-SDRAM address. */
+	writel(0, ram_address);
+
+	/*
+	 * Write the refresh rate into the COUNT field in the MPDDRC
+	 * Refresh Timer Register (MPDDRC_RTR):
+	 */
+	writel(mpddr_value->rtr, &mpddr->rtr);
+
+	return 0;
+}