Exynos5420: Remove code for enabling read leveling

This patch intends to remove all code which enables hardware read
leveling. We need to disable h/w read leveling because new ASV table
is merged in kernel (which is based on the new characterization
condition) and new characterization environment has h/w read leveling
disabled, so we should also disable this. Also, disabling h/w read
leveling improves the MIF LVcc value (LVcc value is the value at which
DDR will fail to work properly), improve LVcc means we have enough
voltage margin for MIF. When h/w leveling is enabled, we have almost
zero volatge margin.

This was ported from: https://gerrit.chromium.org/gerrit/66070
Signed-off-by: David Hendricks <dhendrix@chromium.org>

Change-Id: Id0a2d77e6214325f226d51ae08464b39424cea83
Reviewed-on: https://chromium-review.googlesource.com/66994
Reviewed-by: Gabe Black <gabeblack@chromium.org>
Commit-Queue: David Hendricks <dhendrix@chromium.org>
Tested-by: David Hendricks <dhendrix@chromium.org>
(cherry picked from commit d29add98f52876aaed4fee2b76edf6b4591e66e8)
Signed-off-by: Isaac Christensen <isaac.christensen@se-eng.com>
Reviewed-on: http://review.coreboot.org/6610
Reviewed-by: David Hendricks <dhendrix@chromium.org>
Tested-by: build bot (Jenkins)
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>

1 files changed, 0 insertions, 64 deletions

diff --git a/src/cpu/samsung/exynos5420/dmc_init_ddr3.c b/src/cpu/samsung/exynos5420/dmc_init_ddr3.c
index 6c774a04f5..e236e99022 100644
--- a/src/cpu/samsung/exynos5420/dmc_init_ddr3.c
+++ b/src/cpu/samsung/exynos5420/dmc_init_ddr3.c
@@ -323,67 +323,6 @@ int ddr3_mem_ctrl_init(struct mem_timings *mem, int interleave_size, int reset)
 		writel(val, &drex1->directcmd);
 		writel(val | (0x1 << DIRECT_CMD_CHIP_SHIFT), &drex1->directcmd);
 
-		/* Set Read DQ Calibration */
-		val = (0x3 << DIRECT_CMD_BANK_SHIFT) | 0x4;
-		writel(val, &drex0->directcmd);
-		writel(val | (0x1 << DIRECT_CMD_CHIP_SHIFT), &drex0->directcmd);
-		writel(val, &drex1->directcmd);
-		writel(val | (0x1 << DIRECT_CMD_CHIP_SHIFT), &drex1->directcmd);
-
-
-		val = readl(&phy0_ctrl->phy_con1);
-		val |= READ_LEVELLING_DDR3;
-		writel(val, &phy0_ctrl->phy_con1);
-		val = readl(&phy1_ctrl->phy_con1);
-		val |= READ_LEVELLING_DDR3;
-		writel(val, &phy1_ctrl->phy_con1);
-
-		val = readl(&phy0_ctrl->phy_con2);
-		val |= (RDLVL_EN | RDLVL_INCR_ADJ);
-		writel(val, &phy0_ctrl->phy_con2);
-		val = readl(&phy1_ctrl->phy_con2);
-		val |= (RDLVL_EN | RDLVL_INCR_ADJ);
-		writel(val, &phy1_ctrl->phy_con2);
-
-		setbits_le32(&drex0->rdlvl_config, CTRL_RDLVL_DATA_ENABLE);
-		i = TIMEOUT;
-		while (((readl(&drex0->phystatus) & RDLVL_COMPLETE_CHO) !=
-			RDLVL_COMPLETE_CHO) && (i > 0)) {
-			/*
-			 * TODO(waihong): Comment on how long this take to
-			 * timeout
-			 */
-			udelay(1);
-			i--;
-		}
-		if (!i)
-			return SETUP_ERR_RDLV_COMPLETE_TIMEOUT;
-		clrbits_le32(&drex0->rdlvl_config, CTRL_RDLVL_DATA_ENABLE);
-
-		setbits_le32(&drex1->rdlvl_config, CTRL_RDLVL_DATA_ENABLE);
-		i = TIMEOUT;
-		while (((readl(&drex1->phystatus) & RDLVL_COMPLETE_CHO) !=
-			RDLVL_COMPLETE_CHO) && (i > 0)) {
-			/*
-			 * TODO(waihong): Comment on how long this take to
-			 * timeout
-			 */
-			udelay(1);
-			i--;
-		}
-		if (!i)
-			return SETUP_ERR_RDLV_COMPLETE_TIMEOUT;
-		clrbits_le32(&drex1->rdlvl_config, CTRL_RDLVL_DATA_ENABLE);
-
-		val = (0x3 << DIRECT_CMD_BANK_SHIFT);
-		writel(val, &drex0->directcmd);
-		writel(val | (0x1 << DIRECT_CMD_CHIP_SHIFT), &drex0->directcmd);
-		writel(val, &drex1->directcmd);
-		writel(val | (0x1 << DIRECT_CMD_CHIP_SHIFT), &drex1->directcmd);
-
-		update_reset_dll(drex0, DDR_MODE_DDR3);
-		update_reset_dll(drex1, DDR_MODE_DDR3);
-
 		/* Common Settings for Leveling */
 		val = PHY_CON12_RESET_VAL;
 		writel((val + nLockW_phy0), &phy0_ctrl->phy_con12);
@@ -391,9 +330,6 @@ int ddr3_mem_ctrl_init(struct mem_timings *mem, int interleave_size, int reset)
 
 		setbits_le32(&phy0_ctrl->phy_con2, DLL_DESKEW_EN);
 		setbits_le32(&phy1_ctrl->phy_con2, DLL_DESKEW_EN);
-
-		update_reset_dll(drex0, DDR_MODE_DDR3);
-		update_reset_dll(drex1, DDR_MODE_DDR3);
 	}
 
 	/* Send PALL command */