From ac4fef83454243d75571bac627a8ec15d3fcd405 Mon Sep 17 00:00:00 2001 From: Neil Chen Date: Wed, 24 Sep 2014 10:41:08 +0800 Subject: tegra124: use known-good drive for fast-train only A higher drive setting is used for fast link training, once the link training succeeds, a known-good drive setting will be used for the main stream transactions. For full link training sequence, the sink devices may ask for a preferred drive setting, thus this drive setting should be used for the main stream transactions too. BUG=chrome-os-partner:32129 TEST=all panels on blaze/big devices work fine. Original-Change-Id: Icc540650dc1329af07fd9ee4661eb7fad435fde4 Original-Signed-off-by: Neil Chen Original-Reviewed-on: https://chromium-review.googlesource.com/219544 Original-Reviewed-by: Julius Werner (cherry picked from commit 13d6accfdbe678e785851057f0800a3bbef11bea) Signed-off-by: Aaron Durbin Change-Id: If2fe7d5621f15aa3134d2a3920220e149bb64be6 Reviewed-on: http://review.coreboot.org/9248 Tested-by: build bot (Jenkins) Reviewed-by: Marc Jones --- src/soc/nvidia/tegra124/dp.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'src/soc/nvidia/tegra124/dp.c') diff --git a/src/soc/nvidia/tegra124/dp.c b/src/soc/nvidia/tegra124/dp.c index 9ff50ead8d..35a5c73036 100644 --- a/src/soc/nvidia/tegra124/dp.c +++ b/src/soc/nvidia/tegra124/dp.c @@ -1254,6 +1254,9 @@ static int tegra_dp_do_link_training(struct tegra_dc_dp_data *dp, printk(BIOS_ERR, "dp: full link training failed\n"); return ret; } + } else { + /* set to a known-good drive setting if fast link succeeded */ + tegra_dc_sor_set_voltage_swing(&dp->sor); } /* Everything goes well, double check the link config */ -- cgit v1.2.3