google/oak: increase the driving strength for 4GB DRAMs
Some PVT units encountered DRAM calibration failure during power on/off
tests. The failure is caused by higher impedance of the DRAM on those units.
So increase the driving strength for 4GB DRAMs.
BUG=chrome-os-partner:57392
TEST=run cold reboot 100 times on PVT units which have DRAM calibration issue.
Change-Id: I0d1776cd1a5892d1f82e9bf414620d1ef6d29132
Signed-off-by: PH Hsu <ph.hsu@mediatek.com>
Reviewed-on: https://chromium-review.googlesource.com/394451
Commit-Ready: Yidi Lin <yidi.lin@mediatek.com>
Tested-by: Yidi Lin <yidi.lin@mediatek.com>
Reviewed-by: Pin-Huan Hsu <ph.hsu@mediatek.com>
Reviewed-by: Julius Werner <jwerner@chromium.org>
Reviewed-by: Daniel Kurtz <djkurtz@chromium.org>
diff --git a/src/mainboard/google/oak/sdram_inf/sdram-lpddr3-K4E6E304EB-4GB.inc b/src/mainboard/google/oak/sdram_inf/sdram-lpddr3-K4E6E304EB-4GB.inc
index 0fe16a6..f03f858 100644
--- a/src/mainboard/google/oak/sdram_inf/sdram-lpddr3-K4E6E304EB-4GB.inc
+++ b/src/mainboard/google/oak/sdram_inf/sdram-lpddr3-K4E6E304EB-4GB.inc
@@ -1,7 +1,7 @@
{ /* 4GB (16Gb + 16Gb) for dual rank dram setting */
{
- .impedance_drvp = 0x9,
- .impedance_drvn = 0xa,
+ .impedance_drvp = 0xc,
+ .impedance_drvn = 0xd,
.datlat_ucfirst = 19,
.ca_train = {
diff --git a/src/mainboard/google/oak/sdram_inf/sdram-lpddr3-K4E6E304EE-4GB.inc b/src/mainboard/google/oak/sdram_inf/sdram-lpddr3-K4E6E304EE-4GB.inc
index e6c3a83..a9fbcf1 100644
--- a/src/mainboard/google/oak/sdram_inf/sdram-lpddr3-K4E6E304EE-4GB.inc
+++ b/src/mainboard/google/oak/sdram_inf/sdram-lpddr3-K4E6E304EE-4GB.inc
@@ -1,7 +1,7 @@
{ /* 4GB (16Gb + 16Gb) for dual rank dram setting */
{
- .impedance_drvp = 0x9,
- .impedance_drvn = 0xa,
+ .impedance_drvp = 0xc,
+ .impedance_drvn = 0xd,
.datlat_ucfirst = 18,
.ca_train = {
diff --git a/src/mainboard/google/oak/sdram_inf/sdram-lpddr3-hynix-4GB.inc b/src/mainboard/google/oak/sdram_inf/sdram-lpddr3-hynix-4GB.inc
index 099a07c..6e3b203 100644
--- a/src/mainboard/google/oak/sdram_inf/sdram-lpddr3-hynix-4GB.inc
+++ b/src/mainboard/google/oak/sdram_inf/sdram-lpddr3-hynix-4GB.inc
@@ -1,7 +1,7 @@
{ /* 2GB (8Gb + 8Gb) for single rank dram setting */
{
- .impedance_drvp = 0x9,
- .impedance_drvn = 0xa,
+ .impedance_drvp = 0xc,
+ .impedance_drvn = 0xd,
.datlat_ucfirst = 19,
.ca_train = {
