Commit de84d580 authored by George Shen's avatar George Shen Committed by Alex Deucher
Browse files

drm/amd/display: Read LTTPR ALPM caps during link cap retrieval 



[Why]
The latest DP spec requires the DP TX to read DPCD F0000h through F0009h
when detecting LTTPR capabilities for the first time.

[How]
Update LTTPR cap retrieval to read up to F0009h (two more bytes than the
previous F0007h), and store the LTTPR ALPM capabilities.

Reviewed-by: default avatarWenjing Liu <wenjing.liu@amd.com>
Signed-off-by: default avatarGeorge Shen <george.shen@amd.com>
Signed-off-by: default avatarRoman Li <roman.li@amd.com>
Tested-by: default avatarDaniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: default avatarAlex Deucher <alexander.deucher@amd.com>
parent 5f7e384a

drivers/gpu/drm/amd/display/dc/dc_dp_types.h

+12 −0
Original line number Diff line number Diff line
@@ -959,6 +959,14 @@ union dp_128b_132b_supported_lttpr_link_rates { 
	uint8_t raw;

};



union dp_alpm_lttpr_cap {

	struct {

		uint8_t AUX_LESS_ALPM_SUPPORTED	:1;

		uint8_t RESERVED				:7;

	} bits;

	uint8_t raw;

};



union dp_sink_video_fallback_formats {

	struct {

		uint8_t dp_1024x768_60Hz_24bpp_support	:1;
@@ -1118,6 +1126,7 @@ struct dc_lttpr_caps { 
	uint8_t max_ext_timeout;

	union dp_main_link_channel_coding_lttpr_cap main_link_channel_coding;

	union dp_128b_132b_supported_lttpr_link_rates supported_128b_132b_rates;

	union dp_alpm_lttpr_cap alpm;

	uint8_t aux_rd_interval[MAX_REPEATER_CNT - 1];

};
@@ -1370,6 +1379,9 @@ struct dp_trace { 
#ifndef DPCD_MAX_UNCOMPRESSED_PIXEL_RATE_CAP

#define DPCD_MAX_UNCOMPRESSED_PIXEL_RATE_CAP    0x221c

#endif

#ifndef DP_LTTPR_ALPM_CAPABILITIES

#define DP_LTTPR_ALPM_CAPABILITIES              0xF0009

#endif

#ifndef DP_REPEATER_CONFIGURATION_AND_STATUS_SIZE

#define DP_REPEATER_CONFIGURATION_AND_STATUS_SIZE	0x50

#endif

drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_capability.c

+5 −1
Original line number Diff line number Diff line
@@ -1502,7 +1502,7 @@ static bool dpcd_read_sink_ext_caps(struct dc_link *link) 


enum dc_status dp_retrieve_lttpr_cap(struct dc_link *link)

{

	uint8_t lttpr_dpcd_data[8] = {0};

	uint8_t lttpr_dpcd_data[10] = {0};

	enum dc_status status;

	bool is_lttpr_present;
@@ -1552,6 +1552,10 @@ enum dc_status dp_retrieve_lttpr_cap(struct dc_link *link) 
			lttpr_dpcd_data[DP_PHY_REPEATER_128B132B_RATES -

							DP_LT_TUNABLE_PHY_REPEATER_FIELD_DATA_STRUCTURE_REV];



	link->dpcd_caps.lttpr_caps.alpm.raw =

			lttpr_dpcd_data[DP_LTTPR_ALPM_CAPABILITIES -

							DP_LT_TUNABLE_PHY_REPEATER_FIELD_DATA_STRUCTURE_REV];



	/* If this chip cap is set, at least one retimer must exist in the chain

	 * Override count to 1 if we receive a known bad count (0 or an invalid value) */

	if (((link->chip_caps & AMD_EXT_DISPLAY_PATH_CAPS__EXT_CHIP_MASK) == AMD_EXT_DISPLAY_PATH_CAPS__DP_FIXED_VS_EN) &&