From cf1aa5ade856af433fa056f51a20d18553ae241d Mon Sep 17 00:00:00 2001 From: PH Hsu Date: Thu, 6 Oct 2016 12:31:52 +0800 Subject: [PATCH] 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 Reviewed-on: https://chromium-review.googlesource.com/394451 Commit-Ready: Yidi Lin Tested-by: Yidi Lin Reviewed-by: Pin-Huan Hsu Reviewed-by: Julius Werner Reviewed-by: Daniel Kurtz --- .../google/oak/sdram_inf/sdram-lpddr3-K4E6E304EB-4GB.inc | 4 ++-- .../google/oak/sdram_inf/sdram-lpddr3-K4E6E304EE-4GB.inc | 4 ++-- src/mainboard/google/oak/sdram_inf/sdram-lpddr3-hynix-4GB.inc | 4 ++-- 3 files changed, 6 insertions(+), 6 deletions(-) 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 0fe16a6104..f03f858b82 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 e6c3a831e6..a9fbcf17ee 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 099a07c1dc..6e3b203fed 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 = {