drm/amd/display: Force uclk to max for every state

Workaround for now to avoid underflow.

The uclk switch time should really be bumped up to 404, but doing so
would expose p-state hang issues for higher bandwidth display
configurations.

Signed-off-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Signed-off-by: Leo Li <sunpeng.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_pp_smu.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_pp_smu.c
index 086a3bf..592fa49 100644 (file)
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_pp_smu.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_pp_smu.c
@@ -911,11 +911,11 @@ void dm_pp_get_funcs(
                /* todo set_pme_wa_enable cause 4k@6ohz display not light up */
                funcs->nv_funcs.set_pme_wa_enable = NULL;
                /* todo debug waring message */
-               funcs->nv_funcs.set_hard_min_uclk_by_freq = NULL;
+               funcs->nv_funcs.set_hard_min_uclk_by_freq = pp_nv_set_hard_min_uclk_by_freq;
                /* todo  compare data with window driver*/
-               funcs->nv_funcs.get_maximum_sustainable_clocks = NULL;
+               funcs->nv_funcs.get_maximum_sustainable_clocks = pp_nv_get_maximum_sustainable_clocks;
                /*todo  compare data with window driver */
-               funcs->nv_funcs.get_uclk_dpm_states = NULL;
+               funcs->nv_funcs.get_uclk_dpm_states = pp_nv_get_uclk_dpm_states;
                break;
 #endif
        default:

diff --git a/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_resource.c b/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_resource.c
index 3ad6092..d200bc3 100644 (file)
--- a/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_resource.c
+++ b/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_resource.c
@@ -2576,6 +2576,9 @@ static void cap_soc_clocks(
                                                && max_clocks.uClockInKhz != 0)
                        bb->clock_limits[i].dram_speed_mts = (max_clocks.uClockInKhz / 1000) * 16;
 
+               // HACK: Force every uclk to max for now to "disable" uclk switching.
+               bb->clock_limits[i].dram_speed_mts = (max_clocks.uClockInKhz / 1000) * 16;
+
                if ((bb->clock_limits[i].fabricclk_mhz > (max_clocks.fabricClockInKhz / 1000))
                                                && max_clocks.fabricClockInKhz != 0)
                        bb->clock_limits[i].fabricclk_mhz = (max_clocks.fabricClockInKhz / 1000);
@@ -2783,6 +2786,8 @@ static bool init_soc_bounding_box(struct dc *dc,
                                le32_to_cpu(bb->vmm_page_size_bytes);
                dcn2_0_soc.dram_clock_change_latency_us =
                                fixed16_to_double_to_cpu(bb->dram_clock_change_latency_us);
+               // HACK!! Lower uclock latency switch time so we don't switch
+               dcn2_0_soc.dram_clock_change_latency_us = 10;
                dcn2_0_soc.writeback_dram_clock_change_latency_us =
                                fixed16_to_double_to_cpu(bb->writeback_dram_clock_change_latency_us);
                dcn2_0_soc.return_bus_width_bytes =
@@ -2824,6 +2829,7 @@ static bool init_soc_bounding_box(struct dc *dc,
                struct pp_smu_nv_clock_table max_clocks = {0};
                unsigned int uclk_states[8] = {0};
                unsigned int num_states = 0;
+               int i;
                enum pp_smu_status status;
                bool clock_limits_available = false;
                bool uclk_states_available = false;
@@ -2845,6 +2851,10 @@ static bool init_soc_bounding_box(struct dc *dc,
                        clock_limits_available = (status == PP_SMU_RESULT_OK);
                }
 
+               // HACK: Use the max uclk_states value for all elements.
+               for (i = 0; i < num_states; i++)
+                       uclk_states[i] = uclk_states[num_states - 1];
+
                if (clock_limits_available && uclk_states_available && num_states)
                        update_bounding_box(dc, &dcn2_0_soc, &max_clocks, uclk_states, num_states);
                else if (clock_limits_available)