summaryrefslogtreecommitdiff
path: root/arch/arm/cpu
diff options
context:
space:
mode:
authorAkshay Saraswat <akshay.s@samsung.com>2014-05-26 19:18:06 +0530
committerMinkyu Kang <mk7.kang@samsung.com>2014-06-13 17:05:13 +0900
commitaacdd79095b0a7c258a76e4fdfc133af16b07dc0 (patch)
treebfd980302022f2fe4ca4a328a6eb85ecba0d519e /arch/arm/cpu
parentcfde7588d8ad22560e2328574a4f415642170b92 (diff)
Exynos5420: Remove code for enabling read leveling
This patch intends to remove all code which enables hardware read leveling. All characterization environments may not cope up with h/w read leveling enabled, so we must 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). Improving LVcc means we have enough voltage margin for MIF. When h/w leveling is enabled, we have almost zero volatge margin. Signed-off-by: Alim Akhtar <alim.akhtar@samsung.com> Signed-off-by: Akshay Saraswat <akshay.s@samsung.com> Acked-by: Simon Glass <sjg@chromium.org> Tested-by: Simon Glass <sjg@chromium.org> Signed-off-by: Minkyu Kang <mk7.kang@samsung.com>
Diffstat (limited to 'arch/arm/cpu')
-rw-r--r--arch/arm/cpu/armv7/exynos/dmc_init_ddr3.c71
1 files changed, 0 insertions, 71 deletions
diff --git a/arch/arm/cpu/armv7/exynos/dmc_init_ddr3.c b/arch/arm/cpu/armv7/exynos/dmc_init_ddr3.c
index 4481ab46bf..1d6048cbfc 100644
--- a/arch/arm/cpu/armv7/exynos/dmc_init_ddr3.c
+++ b/arch/arm/cpu/armv7/exynos/dmc_init_ddr3.c
@@ -519,77 +519,6 @@ int ddr3_mem_ctrl_init(struct mem_timings *mem, int reset)
&drex1->directcmd);
}
- if (mem->read_leveling_enable) {
- /* Set Read DQ Calibration */
- val = (0x3 << DIRECT_CMD_BANK_SHIFT) | 0x4;
- for (chip = 0; chip < mem->chips_to_configure; chip++) {
- writel(val | (chip << DIRECT_CMD_CHIP_SHIFT),
- &drex0->directcmd);
- writel(val | (chip << 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
- */
- sdelay(100);
- 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
- */
- sdelay(100);
- i--;
- }
- if (!i)
- return SETUP_ERR_RDLV_COMPLETE_TIMEOUT;
-
- clrbits_le32(&drex1->rdlvl_config,
- CTRL_RDLVL_DATA_ENABLE);
-
- val = (0x3 << DIRECT_CMD_BANK_SHIFT);
- for (chip = 0; chip < mem->chips_to_configure; chip++) {
- writel(val | (chip << DIRECT_CMD_CHIP_SHIFT),
- &drex0->directcmd);
- writel(val | (chip << DIRECT_CMD_CHIP_SHIFT),
- &drex1->directcmd);
- }
-
- update_reset_dll(&drex0->phycontrol0, DDR_MODE_DDR3);
- update_reset_dll(&drex1->phycontrol0, DDR_MODE_DDR3);
- }
-
/* Common Settings for Leveling */
val = PHY_CON12_RESET_VAL;
writel((val + n_lock_w_phy0), &phy0_ctrl->phy_con12);