drm/amd/display: Add code comments clock and encode code

This commit adds some comments to make easier to understand the clock
update for DCN 201, the encode function, and other minor comments.

Signed-off-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Acked-by: Roman Li <roman.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --git a/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn201/dcn201_clk_mgr.c b/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn201/dcn201_clk_mgr.c
index 9c90090e73518745d87572daf7e76652267e2d67..f77840dd051ed142a8f175d8dc591391250e4e2e 100644 (file)
--- a/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn201/dcn201_clk_mgr.c
+++ b/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn201/dcn201_clk_mgr.c
@@ -100,7 +100,15 @@ static void dcn201_update_clocks(struct clk_mgr *clk_mgr_base,
 
        if (clk_mgr_base->clks.dispclk_khz == 0 ||
            dc->debug.force_clock_mode & 0x1) {
+               /* this is from resume or boot up, if forced_clock cfg option
+                * used, we bypass program dispclk and DPPCLK, but need set them
+                * for S3.
+                */
+
                force_reset = true;
+               /* force_clock_mode 0x1:  force reset the clock even it is the
+                * same clock as long as it is in Passive level.
+                */
 
                dcn2_read_clocks_from_hw_dentist(clk_mgr_base);
        }
@@ -150,11 +158,14 @@ static void dcn201_update_clocks(struct clk_mgr *clk_mgr_base,
 
        if (dc->config.forced_clocks == false || (force_reset && safe_to_lower)) {
                if (dpp_clock_lowered) {
+                       // if clock is being lowered, increase DTO before lowering refclk
                        dcn20_update_clocks_update_dpp_dto(clk_mgr, context, safe_to_lower);
                        dcn20_update_clocks_update_dentist(clk_mgr, context);
                } else {
+                       // if clock is being raised, increase refclk before lowering DTO
                        if (update_dppclk || update_dispclk)
                                dcn20_update_clocks_update_dentist(clk_mgr, context);
+                       // always update dtos unless clock is lowered and not safe to lower
                        dcn20_update_clocks_update_dpp_dto(clk_mgr, context, safe_to_lower);
                }
        }

diff --git a/drivers/gpu/drm/amd/display/dc/dcn201/dcn201_hubbub.c b/drivers/gpu/drm/amd/display/dc/dcn201/dcn201_hubbub.c
index 09ea65acb2c439bdb8b1f1f1bab92b746c450e55..63798132ed95b3b60430623b6b44a13a0f3d5c92 100644 (file)
--- a/drivers/gpu/drm/amd/display/dc/dcn201/dcn201_hubbub.c
+++ b/drivers/gpu/drm/amd/display/dc/dcn201/dcn201_hubbub.c
@@ -103,5 +103,5 @@ void hubbub201_construct(struct dcn20_hubbub *hubbub,
        hubbub->masks = hubbub_mask;
 
        hubbub->debug_test_index_pstate = 0xB;
-       hubbub->detile_buf_size = 164 * 1024;
+       hubbub->detile_buf_size = 164 * 1024; /* 164KB for DCN2.0 */
 }

diff --git a/drivers/gpu/drm/amd/display/dc/dcn31/dcn31_hpo_dp_stream_encoder.c b/drivers/gpu/drm/amd/display/dc/dcn31/dcn31_hpo_dp_stream_encoder.c
index 45143459eeddcf9a6085249d1a2352f32e514d0f..678db949cfe3ce0a23686c233343409e7a59c0cf 100644 (file)
--- a/drivers/gpu/drm/amd/display/dc/dcn31/dcn31_hpo_dp_stream_encoder.c
+++ b/drivers/gpu/drm/amd/display/dc/dcn31/dcn31_hpo_dp_stream_encoder.c
@@ -474,6 +474,10 @@ static void dcn31_hpo_dp_stream_enc_update_dp_info_packets(
                                &info_frame->hdrsmd,
                                true);
 
+       /* packetIndex 4 is used for send immediate sdp message, and please
+        * use other packetIndex (such as 5,6) for other info packet
+        */
+
        if (info_frame->adaptive_sync.valid)
                enc->vpg->funcs->update_generic_info_packet(
                                enc->vpg,

diff --git a/drivers/gpu/drm/amd/display/dc/resource/Makefile b/drivers/gpu/drm/amd/display/dc/resource/Makefile
index 184b1f23aa774ff9f3828275f712d9035884813e..db9048974d7462fe05239f51ce26884a9964288f 100644 (file)
--- a/drivers/gpu/drm/amd/display/dc/resource/Makefile
+++ b/drivers/gpu/drm/amd/display/dc/resource/Makefile
@@ -102,10 +102,6 @@ AMD_DISPLAY_FILES += $(AMD_DAL_RESOURCE_DCN21)
 
 ###############################################################################
 
-###############################################################################
-
-###############################################################################
-
 RESOURCE_DCN30 = dcn30_resource.o
 
 AMD_DAL_RESOURCE_DCN30 = $(addprefix $(AMDDALPATH)/dc/resource/dcn30/,$(RESOURCE_DCN30))
@@ -202,6 +198,4 @@ AMD_DISPLAY_FILES += $(AMD_DAL_RESOURCE_DCN351)
 
 ###############################################################################
 
-###############################################################################
-
 endif