drm/amd/display: Source minimum HBlank support

[Why]
Some sink devices wish to have access to the minimum
HBlank supported by the ASIC.

[How]
Make the ASIC minimum HBlank available in Source
Device information address 0x340.
Signed-off-by: Ashley Thomas <Ashley.Thomas2@amd.com>
Acked-by: Aurabindo Pillai <aurabindo.pillai@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/dc/core/dc_debug.c

@@ -418,6 +418,8 @@ char *dc_status_to_str(enum dc_status status)
 		return "Fail clk below minimum";
 	case DC_FAIL_CLK_BELOW_CFG_REQUIRED:
 		return "Fail clk below required CFG (hard_min in PPLIB)";
+	case DC_NOT_SUPPORTED:
+		return "The operation is not supported.";
 	case DC_ERROR_UNEXPECTED:
 		return "Unexpected error";
 	}

drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c

@@ -17,16 +17,16 @@
 
 #define DC_LOGGER \
 	link->ctx->logger
-
+#define DC_TRACE_LEVEL_MESSAGE(...) /* do nothing */
 
 #define DP_REPEATER_CONFIGURATION_AND_STATUS_SIZE   0x50
 
-/* maximum pre emphasis level allowed for each voltage swing level*/
-static const enum dc_pre_emphasis voltage_swing_to_pre_emphasis[] = {
-		PRE_EMPHASIS_LEVEL3,
-		PRE_EMPHASIS_LEVEL2,
-		PRE_EMPHASIS_LEVEL1,
-		PRE_EMPHASIS_DISABLED };
+	/* maximum pre emphasis level allowed for each voltage swing level*/
+	static const enum dc_pre_emphasis
+	voltage_swing_to_pre_emphasis[] = { PRE_EMPHASIS_LEVEL3,
+					    PRE_EMPHASIS_LEVEL2,
+					    PRE_EMPHASIS_LEVEL1,
+					    PRE_EMPHASIS_DISABLED };
 
 enum {
 	POST_LT_ADJ_REQ_LIMIT = 6,
@@ -4372,6 +4372,7 @@ void dp_set_fec_enable(struct dc_link *link, bool enable)
 void dpcd_set_source_specific_data(struct dc_link *link)
 {
 	if (!link->dc->vendor_signature.is_valid) {
+		enum dc_status result_write_min_hblank = DC_NOT_SUPPORTED;
 		struct dpcd_amd_signature amd_signature;
 		amd_signature.AMD_IEEE_TxSignature_byte1 = 0x0;
 		amd_signature.AMD_IEEE_TxSignature_byte2 = 0x0;
@@ -4390,6 +4391,30 @@ void dpcd_set_source_specific_data(struct dc_link *link)
 				(uint8_t *)(&amd_signature),
 				sizeof(amd_signature));
 
+		if (link->ctx->dce_version >= DCN_VERSION_2_0 &&
+			link->dc->caps.min_horizontal_blanking_period != 0) {
+
+			uint8_t hblank_size = (uint8_t)link->dc->caps.min_horizontal_blanking_period;
+
+			result_write_min_hblank = core_link_write_dpcd(link,
+				DP_SOURCE_MINIMUM_HBLANK_SUPPORTED, (uint8_t *)(&hblank_size),
+				sizeof(hblank_size));
+		}
+		DC_TRACE_LEVEL_MESSAGE(DAL_TRACE_LEVEL_INFORMATION,
+							WPP_BIT_FLAG_DC_DETECTION_DP_CAPS,
+							"result=%u link_index=%u enum dce_version=%d DPCD=0x%04X min_hblank=%u branch_dev_id=0x%x branch_dev_name='%c%c%c%c%c%c'",
+							result_write_min_hblank,
+							link->link_index,
+							link->ctx->dce_version,
+							DP_SOURCE_MINIMUM_HBLANK_SUPPORTED,
+							link->dc->caps.min_horizontal_blanking_period,
+							link->dpcd_caps.branch_dev_id,
+							link->dpcd_caps.branch_dev_name[0],
+							link->dpcd_caps.branch_dev_name[1],
+							link->dpcd_caps.branch_dev_name[2],
+							link->dpcd_caps.branch_dev_name[3],
+							link->dpcd_caps.branch_dev_name[4],
+							link->dpcd_caps.branch_dev_name[5]);
 	} else {
 		core_link_write_dpcd(link, DP_SOURCE_OUI,
 				link->dc->vendor_signature.data.raw,

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

@@ -156,6 +156,7 @@ struct dc_caps {
 	uint32_t dmdata_alloc_size;
 	unsigned int max_cursor_size;
 	unsigned int max_video_width;
+	unsigned int min_horizontal_blanking_period;
 	int linear_pitch_alignment;
 	bool dcc_const_color;
 	bool dynamic_audio;

drivers/gpu/drm/amd/display/dc/dce100/dce100_resource.c

@@ -1066,6 +1066,7 @@ static bool dce100_resource_construct(
 	dc->caps.i2c_speed_in_khz = 40;
 	dc->caps.i2c_speed_in_khz = 40;
 	dc->caps.max_cursor_size = 128;
+	dc->caps.min_horizontal_blanking_period = 80;
 	dc->caps.dual_link_dvi = true;
 	dc->caps.disable_dp_clk_share = true;
 	dc->caps.extended_aux_timeout_support = false;

drivers/gpu/drm/amd/display/dc/dce110/dce110_resource.c

@@ -1368,6 +1368,7 @@ static bool dce110_resource_construct(
 	dc->caps.i2c_speed_in_khz = 40;
 	dc->caps.i2c_speed_in_khz_hdcp = 40;
 	dc->caps.max_cursor_size = 128;
+	dc->caps.min_horizontal_blanking_period = 80;
 	dc->caps.is_apu = true;
 	dc->caps.extended_aux_timeout_support = false;
 

drivers/gpu/drm/amd/display/dc/dce112/dce112_resource.c

@@ -1235,6 +1235,7 @@ static bool dce112_resource_construct(
 	dc->caps.i2c_speed_in_khz = 100;
 	dc->caps.i2c_speed_in_khz_hdcp = 100; /*1.4 w/a not applied by default*/
 	dc->caps.max_cursor_size = 128;
+	dc->caps.min_horizontal_blanking_period = 80;
 	dc->caps.dual_link_dvi = true;
 	dc->caps.extended_aux_timeout_support = false;
 

drivers/gpu/drm/amd/display/dc/dce120/dce120_resource.c

@@ -1075,6 +1075,7 @@ static bool dce120_resource_construct(
 	dc->caps.i2c_speed_in_khz = 100;
 	dc->caps.i2c_speed_in_khz_hdcp = 100; /*1.4 w/a not applied by default*/
 	dc->caps.max_cursor_size = 128;
+	dc->caps.min_horizontal_blanking_period = 80;
 	dc->caps.dual_link_dvi = true;
 	dc->caps.psp_setup_panel_mode = true;
 	dc->caps.extended_aux_timeout_support = false;

drivers/gpu/drm/amd/display/dc/dce80/dce80_resource.c

@@ -965,6 +965,7 @@ static bool dce80_construct(
 	dc->caps.i2c_speed_in_khz = 40;
 	dc->caps.i2c_speed_in_khz_hdcp = 40;
 	dc->caps.max_cursor_size = 128;
+	dc->caps.min_horizontal_blanking_period = 80;
 	dc->caps.dual_link_dvi = true;
 	dc->caps.extended_aux_timeout_support = false;
 
@@ -1164,6 +1165,7 @@ static bool dce81_construct(
 	dc->caps.i2c_speed_in_khz = 40;
 	dc->caps.i2c_speed_in_khz_hdcp = 40;
 	dc->caps.max_cursor_size = 128;
+	dc->caps.min_horizontal_blanking_period = 80;
 	dc->caps.is_apu = true;
 
 	/*************************************************
@@ -1362,6 +1364,7 @@ static bool dce83_construct(
 	dc->caps.i2c_speed_in_khz = 40;
 	dc->caps.i2c_speed_in_khz_hdcp = 40;
 	dc->caps.max_cursor_size = 128;
+	dc->caps.min_horizontal_blanking_period = 80;
 	dc->caps.is_apu = true;
 
 	/*************************************************

drivers/gpu/drm/amd/display/dc/dcn10/dcn10_resource.c

@@ -1418,6 +1418,7 @@ static bool dcn10_resource_construct(
 	dc->caps.i2c_speed_in_khz = 100;
 	dc->caps.i2c_speed_in_khz_hdcp = 100; /*1.4 w/a not applied by default*/
 	dc->caps.max_cursor_size = 256;
+	dc->caps.min_horizontal_blanking_period = 80;
 	dc->caps.max_slave_planes = 1;
 	dc->caps.is_apu = true;
 	dc->caps.post_blend_color_processing = false;

drivers/gpu/drm/amd/display/dc/dcn20/dcn20_resource.c

@@ -3813,6 +3813,7 @@ static bool dcn20_resource_construct(
 	dc->caps.i2c_speed_in_khz = 100;
 	dc->caps.i2c_speed_in_khz_hdcp = 100; /*1.4 w/a not applied by default*/
 	dc->caps.max_cursor_size = 256;
+	dc->caps.min_horizontal_blanking_period = 80;
 	dc->caps.dmdata_alloc_size = 2048;
 
 	dc->caps.max_slave_planes = 1;

drivers/gpu/drm/amd/display/dc/dcn21/dcn21_resource.c

@@ -1930,6 +1930,7 @@ static bool dcn21_resource_construct(
 	dc->caps.i2c_speed_in_khz = 100;
 	dc->caps.i2c_speed_in_khz_hdcp = 5; /*1.4 w/a applied by default*/
 	dc->caps.max_cursor_size = 256;
+	dc->caps.min_horizontal_blanking_period = 80;
 	dc->caps.dmdata_alloc_size = 2048;
 
 	dc->caps.max_slave_planes = 1;

drivers/gpu/drm/amd/display/dc/dcn30/dcn30_resource.c

@@ -2606,6 +2606,7 @@ static bool dcn30_resource_construct(
 	dc->caps.i2c_speed_in_khz = 100;
 	dc->caps.i2c_speed_in_khz_hdcp = 100; /*1.4 w/a not applied by default*/
 	dc->caps.max_cursor_size = 256;
+	dc->caps.min_horizontal_blanking_period = 80;
 	dc->caps.dmdata_alloc_size = 2048;
 
 	dc->caps.max_slave_planes = 1;

drivers/gpu/drm/amd/display/dc/inc/core_status.h

@@ -50,6 +50,8 @@ enum dc_status {
 	DC_FAIL_CLK_BELOW_MIN = 22, /*THIS IS MIN PER IP*/
 	DC_FAIL_CLK_BELOW_CFG_REQUIRED = 23, /*THIS IS hard_min in PPLIB*/
 
+	DC_NOT_SUPPORTED = 24,
+
 	DC_ERROR_UNEXPECTED = -1
 };
 

drivers/gpu/drm/amd/display/include/dpcd_defs.h

@@ -156,5 +156,6 @@ enum dpcd_psr_sink_states {
 #define DP_SOURCE_BACKLIGHT_CURRENT_PEAK    0x326
 #define DP_SOURCE_BACKLIGHT_CONTROL	    0x32E
 #define DP_SOURCE_BACKLIGHT_ENABLE	    0x32F
+#define DP_SOURCE_MINIMUM_HBLANK_SUPPORTED	0x340
 
 #endif /* __DAL_DPCD_DEFS_H__ */