6.9-stable review patch. If anyone has any objections, please let me know.
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From: Michael Strauss michael.strauss@amd.com
commit 2ec6c7f802332d1eff16f03e7c757f1543ee1183 upstream.
[WHY] New register field added in DP2.1 SCR, needed for auxless ALPM
[HOW] Echo value read from 0xF0007 back to sink
Reviewed-by: Wenjing Liu wenjing.liu@amd.com Cc: Mario Limonciello mario.limonciello@amd.com Cc: Alex Deucher alexander.deucher@amd.com Cc: stable@vger.kernel.org Signed-off-by: Alex Hung alex.hung@amd.com Signed-off-by: Michael Strauss michael.strauss@amd.com Tested-by: Daniel Wheeler daniel.wheeler@amd.com Signed-off-by: Alex Deucher alexander.deucher@amd.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_capability.c | 10 +++++++++- drivers/gpu/drm/amd/display/include/dpcd_defs.h | 5 +++++ 2 files changed, 14 insertions(+), 1 deletion(-)
--- a/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_capability.c +++ b/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_capability.c @@ -1590,9 +1590,17 @@ static bool retrieve_link_cap(struct dc_ return false; }
- if (dp_is_lttpr_present(link)) + if (dp_is_lttpr_present(link)) { configure_lttpr_mode_transparent(link);
+ // Echo TOTAL_LTTPR_CNT back downstream + core_link_write_dpcd( + link, + DP_TOTAL_LTTPR_CNT, + &link->dpcd_caps.lttpr_caps.phy_repeater_cnt, + sizeof(link->dpcd_caps.lttpr_caps.phy_repeater_cnt)); + } + /* Read DP tunneling information. */ status = dpcd_get_tunneling_device_data(link);
--- a/drivers/gpu/drm/amd/display/include/dpcd_defs.h +++ b/drivers/gpu/drm/amd/display/include/dpcd_defs.h @@ -177,4 +177,9 @@ enum dpcd_psr_sink_states { #define DP_SINK_PR_PIXEL_DEVIATION_PER_LINE 0x379 #define DP_SINK_PR_MAX_NUMBER_OF_DEVIATION_LINE 0x37A
+/* Remove once drm_dp_helper.h is updated upstream */ +#ifndef DP_TOTAL_LTTPR_CNT +#define DP_TOTAL_LTTPR_CNT 0xF000A /* 2.1 */ +#endif + #endif /* __DAL_DPCD_DEFS_H__ */