diff options
Diffstat (limited to 'meta-amd-bsp/recipes-kernel/linux/linux-yocto-4.19.8/4396-drm-amd-display-check-for-dp-rev-before-reading-lttp.patch')
| -rw-r--r-- | meta-amd-bsp/recipes-kernel/linux/linux-yocto-4.19.8/4396-drm-amd-display-check-for-dp-rev-before-reading-lttp.patch | 47 |
1 files changed, 47 insertions, 0 deletions
diff --git a/meta-amd-bsp/recipes-kernel/linux/linux-yocto-4.19.8/4396-drm-amd-display-check-for-dp-rev-before-reading-lttp.patch b/meta-amd-bsp/recipes-kernel/linux/linux-yocto-4.19.8/4396-drm-amd-display-check-for-dp-rev-before-reading-lttp.patch new file mode 100644 index 00000000..12fcd76a --- /dev/null +++ b/meta-amd-bsp/recipes-kernel/linux/linux-yocto-4.19.8/4396-drm-amd-display-check-for-dp-rev-before-reading-lttp.patch @@ -0,0 +1,47 @@ +From 92a6ea98405ccb7b2c47b2480a1e43bbc7e5d1a1 Mon Sep 17 00:00:00 2001 +From: abdoulaye berthe <abdoulaye.berthe@amd.com> +Date: Wed, 18 Sep 2019 11:57:47 -0400 +Subject: [PATCH 4396/4736] drm/amd/display: check for dp rev before reading + lttpr regs + +[Why] +LTTPR was introduced after DP1.2. Reading LTTPR registers 0xFXXXX +on some DP 1.2 display is causing an unexpected behavior. + +[How] +Make sure that we don't read any lttpr registers on 1.2 displays. + +Signed-off-by: abdoulaye berthe <abdoulaye.berthe@amd.com> +Reviewed-by: Aric Cyr <Aric.Cyr@amd.com> +--- + drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c | 5 +++-- + 1 file changed, 3 insertions(+), 2 deletions(-) + +diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c b/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c +index 2a89f90ef7a7..1e4480f3bd3c 100644 +--- a/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c ++++ b/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c +@@ -2759,9 +2759,10 @@ static bool retrieve_link_cap(struct dc_link *link) + /* Set default timeout to 3.2ms and read LTTPR capabilities */ + bool ext_timeout_support = link->dc->caps.extended_aux_timeout_support && + !link->dc->config.disable_extended_timeout_support; ++ link->is_lttpr_mode_transparent = true; ++ + if (ext_timeout_support) { + status = dc_link_aux_configure_timeout(link->ddc, LINK_AUX_DEFAULT_EXTENDED_TIMEOUT_PERIOD); +- link->is_lttpr_mode_transparent = true; + } + + memset(dpcd_data, '\0', sizeof(dpcd_data)); +@@ -2796,7 +2797,7 @@ static bool retrieve_link_cap(struct dc_link *link) + return false; + } + +- if (ext_timeout_support) { ++ if (ext_timeout_support && link->dpcd_caps.dpcd_rev.raw >= 0x14) { + status = core_link_read_dpcd( + link, + DP_PHY_REPEATER_CNT, +-- +2.17.1 + |