pistachio: clean DDR2 initialization code

The proper way to initialize DDR2 is for the PHY to
automatically establish precise timing configuration
through the training process. The alternative (used
initially for testing) is no longer needed.

This change determined the removal of some local
variables as they ended up being used in one location only.

BUG=chrome-os-partner:31438, chrome-os-partner:37087
TEST=tested on Pistachio bring up board -> DDR initialized
     properly and ramstage executed correctly.
BRANCH=none

Change-Id: I31e9a8975d176a04061f9c84fe06cce850bb53b9
Signed-off-by: Patrick Georgi <pgeorgi@chromium.org>
Original-Commit-Id: e28f3ef9a22436bb0fa949df6f5a5c6a67002dfd
Original-Change-Id: Ifb9c1bb6e0b71af72340381bd2349850d1b4af2d
Original-Signed-off-by: Ionela Voinescu <ionela.voinescu@imgtec.com>
Original-Reviewed-on: https://chromium-review.googlesource.com/256303
Original-Reviewed-by: David Hendricks <dhendrix@chromium.org>
Reviewed-on: http://review.coreboot.org/9845
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>

1 files changed, 15 insertions, 155 deletions

diff --git a/src/soc/imgtec/pistachio/ddr2_init.c b/src/soc/imgtec/pistachio/ddr2_init.c
index 0ffa2bc..e236c1c 100644
--- a/src/soc/imgtec/pistachio/ddr2_init.c
+++ b/src/soc/imgtec/pistachio/ddr2_init.c
@@ -120,7 +120,6 @@
 #define DDRPHY_DLLGCR_OFFSET		(0x0010)
 
 #define BL8		1
-#define UMCTL_INIT	0
 
 #define DDR_TIMEOUT_VALUE_US		100000
 
@@ -143,9 +142,6 @@ static int wait_for_completion(u32 reg, u32 exp_val)
 int init_ddr2(void)
 {
 
-	u32 exp_val;
-	u32 mr, md_dllrst, emr, emr2, emr3;
-
 	/*
 	 * Reset the AXI bridge and DDR Controller in case any spurious
 	 * writes have already happened to DDR - note must be done together,
@@ -153,17 +149,14 @@ int init_ddr2(void)
 	 */
 	write32(TOPLEVEL_REGS + DDR_CTRL_OFFSET, 0x00000000);
 	write32(TOPLEVEL_REGS + DDR_CTRL_OFFSET, 0x0000000F);
-
 	/*
 	 * Dummy read to fence the access between the reset above
 	 * and thw DDR controller writes below
 	 */
 	read32(TOPLEVEL_REGS + DDR_CTRL_OFFSET);
-
 	/* Timings for 400MHz
 	 * therefore 200MHz (5ns) uMCTL (Internal) Rate
 	 */
-
 	/* TOGCNT1U: Toggle Counter 1U Register: 1us 200h C8h */
 	write32(DDR_PCTL + DDR_PCTL_TOGCNT1U_OFFSET, 0x000000C8);
 	/* TINIT: t_init Timing Register: at least 200us 200h C8h */
@@ -221,9 +214,8 @@ int init_ddr2(void)
 	 * 31 TPD LPDDR2 0
 	 */
 	write32(DDR_PHY + DDRPHY_DCR_OFFSET, 0x0000000A);
-	/* Generate to use with PHY and PCTL */
-	md_dllrst = 0x0B62 | (BL8 ? 0x1 : 0x0);
 	/* Generate to use with PHY and PCTL
+	 * MR0 : MR Register, bits 12:0 imported dfrom MR
 	 * 2:0 BL 8 011
 	 * 3 BT Sequential 0 Interleaved 1 = 0
 	 * 6:4 CL 6
@@ -231,46 +223,34 @@ int init_ddr2(void)
 	 * 8 DLL Reset 1 (self Clearing)
 	 * 11:9 WR 15 ns 6 (101)
 	 * 12 PD Slow 1 Fast 0 0
-	 */
-	mr = 0x0A62 | (BL8 ? 0x1 : 0x0);
-	/* MR0 : MR Register, bits 12:0 imported dfrom MR
-	 * 12:0 md_dllrst
-	 * c15:13 RSVD RSVD
+	 * 15:13 RSVD RSVD
 	 * 31:16 Reserved
 	 */
-	write32(DDR_PHY + DDRPHY_MR_OFFSET, 0x00000000 | mr);
-	/* Generate to use with PHY and PCTL
+	write32(DDR_PHY + DDRPHY_MR_OFFSET, 0x00000A62 | (BL8 ? 0x1 : 0x0));
+	/* MR1 : EMR Register
+	 * Generate to use with PHY and PCTL
 	 * 0 DE DLL Enable 0 Disable 1
 	 * 1 DIC Output Driver Imp Ctl 0 Full, 1 Half
-	 * 6,2 ODT 0 Disable, 1 75R, 2 150R, 3 50R = 1
+	 * 6,2 ODT 0 Disable, 1 75R, 2 150R, 3 50R; LSB: 2, MSB: 6
 	 * 5:3 AL = 0
 	 * 9:7 OCD = 0
 	 * 10 DQS 0 diff, 1 single = 0
 	 * 11 RDQS NA 0
 	 * 12 QOFF Normal mode 0
-	 */
-	emr = 0x4;
-	/* MR1 : EMR Register
-	 * 12:0 EMR1
 	 * 15:13 RSVD
 	 * 31:16 Reserved
 	 */
-	write32(DDR_PHY + DDRPHY_EMR_OFFSET, 0x00000000 | emr);
-
-	/* Generate to use with PHY and PCTL
+	write32(DDR_PHY + DDRPHY_EMR_OFFSET, 0x00000004);
+	/* MR2 : EMR2 Register
+	 * Generate to use with PHY and PCTL
 	 * 2:0 PASR, NA 000
 	 * 3 DDC NA 0
 	 * 6:4 RSVD
 	 * 7 SFR 0
-	 */
-	emr2 = 0x0;
-	/* MR2 : EMR2 Register
-	 * 7:0 EMR2
 	 * 15:8 RSVD
 	 * 31:16 Reserved
 	 */
-	write32(DDR_PHY + DDRPHY_EMR2_OFFSET, 0x00000000 | emr2);
-	emr3 = 0x0;
+	write32(DDR_PHY + DDRPHY_EMR2_OFFSET, 0x00000000);
 	/* DSGCR
 	 * 0 PUREN Def 1
 	 * 1 BDISEN Def 1
@@ -339,51 +319,24 @@ int init_ddr2(void)
 	 * 29:19 : tDINIT1 DRAM Init time 400ns 160 Dec 0xA0
 	 */
 	write32(DDR_PHY + DDRPHY_PTR1_OFFSET, 0x05013880);
-
 	/* PGSR : Wait for INIT/DLL/Z Done from Power on Reset */
 	if (wait_for_completion(DDR_PHY + DDRPHY_PGSR_OFFSET, 0x00000007))
 		return DDR_TIMEOUT;
-
-	if (UMCTL_INIT == 1) {
-		/* PIR : Trigger INIT/DLL/Z following soft reset of DLL & ITM */
-		write32(DDR_PHY + DDRPHY_PIR_OFFSET, 0x0000001F);
-
-		/* PGSR : Wait for INIT?DLL?Z Done from SOFT Reset */
-		if (wait_for_completion(DDR_PHY + DDRPHY_PGSR_OFFSET,
-						0x00000007))
-			return DDR_TIMEOUT;
-
-		/* PIR : use uMCTL for DRAM Init */
-		write32(DDR_PHY + DDRPHY_PIR_OFFSET, 0x00040001);
-
-		/* PGSR : Wait for DRAM Init Done */
-		if (wait_for_completion(DDR_PHY + DDRPHY_PGSR_OFFSET,
-						0x0000000F))
+	/* PIR : use PHY for DRAM Init */
+	write32(DDR_PHY + DDRPHY_PIR_OFFSET, 0x000001DF);
+	/* PGSR : Wait for DRAM Init Done */
+	if (wait_for_completion(DDR_PHY + DDRPHY_PGSR_OFFSET, 0x0000001F))
 			return DDR_TIMEOUT;
-
-	} else {
-		/* PIR : use uMCTL for DRAM Init */
-		write32(DDR_PHY + DDRPHY_PIR_OFFSET, 0x000001DF);
-		/* PGSR : Wait for DRAM Init Done */
-
-		if (wait_for_completion(DDR_PHY + DDRPHY_PGSR_OFFSET,
-						0x0000001F))
-			return DDR_TIMEOUT;
-	}
-
 	/* DF1STAT0 : wait for DFI_INIT_COMPLETE */
 	if (wait_for_completion(DDR_PCTL + DDR_PCTL_DFISTAT0_OFFSET,
 						0x00000001))
 		return DDR_TIMEOUT;
-
 	/* POWCTL : Start the memory Power Up seq*/
 	write32(DDR_PCTL + DDR_PCTL_POWCTL_OFFSET, 0x00000001);
-
 	/* POWSTAT : wait for POWER_UP_DONE */
 	if (wait_for_completion(DDR_PCTL + DDR_PCTL_POWSTAT_OFFSET,
 						0x00000001))
 		return DDR_TIMEOUT;
-
 	/*
 	 * TREFI : t_refi Timing Register 1X
 	 * 12:0 t_refi 7.8us in 100ns 0x4E
@@ -499,18 +452,14 @@ int init_ddr2(void)
 	 * 30:24 Reserved
 	 */
 	write32(DDR_PCTL + DDR_PCTL_MCMD_OFFSET, 0x80100001);
-
 	/* MRS cmd wait for completion */
 	if (wait_for_completion(DDR_PCTL + DDR_PCTL_MCMD_OFFSET, 0x00100001))
 		return DDR_TIMEOUT;
-
 	/* SCTL : UPCTL switch INIT CONFIG State */
 	write32(DDR_PCTL + DDR_PCTL_SCTL_OFFSET, 0x00000001);
-
 	/* STAT : Wait for Switch INIT to Config State */
 	if (wait_for_completion(DDR_PCTL + DDR_PCTL_STAT_OFFSET, 0x00000001))
 		return DDR_TIMEOUT;
-
 	/* DFISTCFG0 : Drive various DFI signals appropriately
 	 * 0 dfi_init_start            0
 	 * 1 dfi_freq_ratio_en         1
@@ -549,7 +498,6 @@ int init_ddr2(void)
 	 * 3 rank0_odt_write_sel  1
 	 */
 	write32(DDR_PCTL + DDR_PCTL_DFIODTCFG_OFFSET, 0x00000008);
-
 	/* DFIODTCFG1 : DFI ODT Configuration
 	 * 4:0   odt_lat_w     4
 	 * 12:8  odt_lat_r     0 Def
@@ -557,92 +505,6 @@ int init_ddr2(void)
 	 * 12:8  odt_len_bl8_r 6 Def
 	 */
 	write32(DDR_PCTL + DDR_PCTL_DFIODTCFG1_OFFSET, 0x06060004);
-
-	if (UMCTL_INIT == 1) {
-		/* MCMD : Deselect command */
-		write32(DDR_PCTL + DDR_PCTL_MCMD_OFFSET, 0x80100000);
-		if (wait_for_completion(DDR_PCTL + DDR_PCTL_MCMD_OFFSET,
-							0x00100000))
-			return DDR_TIMEOUT;
-
-		/* MCMD : Precharge ALL Banks */
-		write32(DDR_PCTL + DDR_PCTL_MCMD_OFFSET, 0x80100001);
-		if (wait_for_completion(DDR_PCTL + DDR_PCTL_MCMD_OFFSET,
-					0x00100001))
-			return DDR_TIMEOUT;
-
-		/* MCMD : MRS Cmd, EMR2 -- High Temp Self refresh Disable */
-		write32(DDR_PCTL + DDR_PCTL_MCMD_OFFSET,
-			0x80140003 | (emr2 << 4));
-		exp_val = (0x00140003 | (emr2 << 4));
-		if (wait_for_completion(DDR_PCTL + DDR_PCTL_MCMD_OFFSET,
-					exp_val))
-			return DDR_TIMEOUT;
-
-		/* MCMD : MRS cmd, EMR3 */
-		write32(DDR_PCTL + DDR_PCTL_MCMD_OFFSET,
-			0x80160003 | (emr3 << 4));
-		exp_val = (0x00160003 | (emr3 << 4));
-		if (wait_for_completion(DDR_PCTL + DDR_PCTL_MCMD_OFFSET,
-					exp_val))
-			return DDR_TIMEOUT;
-
-		/* MCMD : MRS Cmd, EMR-- DLL Enable */
-		write32(DDR_PCTL + DDR_PCTL_MCMD_OFFSET,
-			0x80120003 | (emr << 4));
-		exp_val = (0x00120003 | (emr << 4));
-		if (wait_for_completion(DDR_PCTL + DDR_PCTL_MCMD_OFFSET,
-					exp_val))
-			return DDR_TIMEOUT;
-
-		/* MCMD : MRS Cmd, MR--DLL Reset */
-		write32(DDR_PCTL + DDR_PCTL_MCMD_OFFSET,
-			(0x80100003 | (md_dllrst << 4)));
-		if (wait_for_completion(DDR_PCTL + DDR_PCTL_MCMD_OFFSET,
-					0x80000000))
-			return DDR_TIMEOUT;
-
-		/* MCMD : Precharge ALL Banks */
-		write32(DDR_PCTL + DDR_PCTL_MCMD_OFFSET, 0x80100001);
-		if (wait_for_completion(DDR_PCTL + DDR_PCTL_MCMD_OFFSET,
-					0x00100001))
-			return DDR_TIMEOUT;
-
-		/* MCMD : Refresh Command */
-		write32(DDR_PCTL + DDR_PCTL_MCMD_OFFSET, 0x80100002);
-		if (wait_for_completion(DDR_PCTL + DDR_PCTL_MCMD_OFFSET,
-					0x00100002))
-			return DDR_TIMEOUT;
-
-		/* MCMD : Refresh Command */
-		write32(DDR_PCTL + DDR_PCTL_MCMD_OFFSET, 0x80100002);
-		if (wait_for_completion(DDR_PCTL + DDR_PCTL_MCMD_OFFSET,
-					0x00100002))
-			return DDR_TIMEOUT;
-
-		/* MCMD : MRS Cmd, MR0-- Initialize Device Operation */
-		write32(DDR_PCTL + DDR_PCTL_MCMD_OFFSET,
-			0x80100003 | (mr << 4));
-		if (wait_for_completion(DDR_PCTL + DDR_PCTL_MCMD_OFFSET, 0x0))
-			return DDR_TIMEOUT;
-
-		/* MCMD : MRS Cmd, MR1-- Set OCD Calibration Default */
-		write32(DDR_PCTL + DDR_PCTL_MCMD_OFFSET,
-			0x80123803 | (emr << 4));
-		exp_val = (0x00123803 | (emr << 4));
-		if (wait_for_completion(DDR_PCTL + DDR_PCTL_MCMD_OFFSET,
-					exp_val))
-			return DDR_TIMEOUT;
-
-		/* MCMD : MRS Cmd, MR1-- Exit OCD calibration Mode */
-		write32(DDR_PCTL + DDR_PCTL_MCMD_OFFSET,
-			0x80120003 | (emr << 4));
-		exp_val = (0x00120003 | (emr << 4));
-		if (wait_for_completion(DDR_PCTL + DDR_PCTL_MCMD_OFFSET,
-					exp_val))
-			return DDR_TIMEOUT;
-	}
-
 	/* DCFG : DRAM Density 256 Mb 16 Bit IO Width
 	 * 1:0  Devicw Width 1 x8, 2 x16, 3 x32  2
 	 * 5:2  Density 2Gb = 5
@@ -652,13 +514,11 @@ int init_ddr2(void)
 	 * 31:11 Reserved
 	 */
 	write32(DDR_PCTL + DDR_PCTL_DCFG_OFFSET, 0x00000016);
-
 	/* PCFG_0 : Port 0 AXI config  */
-	if (BL8 == 1)
+	if (BL8)
 		write32(DDR_PCTL + DDR_PCTL_PCFG0_OFFSET, 0x000800A0);
 	else
 		write32(DDR_PCTL + DDR_PCTL_PCFG0_OFFSET, 0x000400A0);
-
 	/* SCTL : UPCTL switch Config to ACCESS State */
 	write32(DDR_PCTL + DDR_PCTL_SCTL_OFFSET, 0x00000002);
 	/* STAT : Wait for switch CFG -> GO State */