From: George Shen <george.shen@xxxxxxx>
[Why]
Current DCN3.2 logic for finding the dummy P-state index uses the
DCN3.0 DML validation function instead of DCN3.2 DML.
This can result in either unexpected DML VBA values, or unexpected
dummy P-state index to be used.
[How]
Update the dummy P-state logic to use DCN3.2 DML validation function.
Reviewed-by: Alvin Lee <alvin.lee2@xxxxxxx>
Reviewed-by: Nevenko Stupar <Nevenko.Stupar@xxxxxxx>
Acked-by: Wayne Lin <wayne.lin@xxxxxxx>
Signed-off-by: George Shen <george.shen@xxxxxxx>
---
.../drm/amd/display/dc/dml/dcn32/dcn32_fpu.c | 46 ++++++++++++++++++-
.../drm/amd/display/dc/dml/dcn32/dcn32_fpu.h | 6 +++
2 files changed, 51 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/amd/display/dc/dml/dcn32/dcn32_fpu.c b/drivers/gpu/drm/amd/display/dc/dml/dcn32/dcn32_fpu.c
index b8d4547a885f..b573ab7b81ed 100644
--- a/drivers/gpu/drm/amd/display/dc/dml/dcn32/dcn32_fpu.c
+++ b/drivers/gpu/drm/amd/display/dc/dml/dcn32/dcn32_fpu.c
@@ -243,6 +243,50 @@ void dcn32_build_wm_range_table_fpu(struct clk_mgr_internal *clk_mgr)
clk_mgr->base.bw_params->wm_table.nv_entries[WM_D].pmfw_breakdown.max_uclk = 0xFFFF;
}
+/**
+ * Finds dummy_latency_index when MCLK switching using firmware based
+ * vblank stretch is enabled. This function will iterate through the
+ * table of dummy pstate latencies until the lowest value that allows
+ * dm_allow_self_refresh_and_mclk_switch to happen is found
+ */
+int dcn32_find_dummy_latency_index_for_fw_based_mclk_switch(struct dc *dc,
+ struct dc_state *context,
+ display_e2e_pipe_params_st *pipes,
+ int pipe_cnt,
+ int vlevel)
+{
+ const int max_latency_table_entries = 4;
+ const struct vba_vars_st *vba = &context->bw_ctx.dml.vba;
+ int dummy_latency_index = 0;
+
+ dc_assert_fp_enabled();
+
+ while (dummy_latency_index < max_latency_table_entries) {
+ context->bw_ctx.dml.soc.dram_clock_change_latency_us =
+ dc->clk_mgr->bw_params->dummy_pstate_table[dummy_latency_index].dummy_pstate_latency_us;
+ dcn32_internal_validate_bw(dc, context, pipes, &pipe_cnt, &vlevel, false);
+
+ if (vlevel < context->bw_ctx.dml.vba.soc.num_states &&
+ vba->DRAMClockChangeSupport[vlevel][vba->maxMpcComb] != dm_dram_clock_change_unsupported)
+ break;
+
+ dummy_latency_index++;
+ }
+
+ if (dummy_latency_index == max_latency_table_entries) {
+ ASSERT(dummy_latency_index != max_latency_table_entries);
+ /* If the execution gets here, it means dummy p_states are
+ * not possible. This should never happen and would mean
+ * something is severely wrong.
+ * Here we reset dummy_latency_index to 3, because it is
+ * better to have underflows than system crashes.
+ */
+ dummy_latency_index = max_latency_table_entries - 1;
+ }
+
+ return dummy_latency_index;
+}
+
/**
* dcn32_helper_populate_phantom_dlg_params - Get DLG params for phantom pipes
* and populate pipe_ctx with those params.
@@ -1723,7 +1767,7 @@ void dcn32_calculate_wm_and_dlg_fpu(struct dc *dc, struct dc_state *context,
dcn30_can_support_mclk_switch_using_fw_based_vblank_stretch(dc, context);
if (context->bw_ctx.bw.dcn.clk.fw_based_mclk_switching) {
- dummy_latency_index = dcn30_find_dummy_latency_index_for_fw_based_mclk_switch(dc,
+ dummy_latency_index = dcn32_find_dummy_latency_index_for_fw_based_mclk_switch(dc,
context, pipes, pipe_cnt, vlevel);
/* After calling dcn30_find_dummy_latency_index_for_fw_based_mclk_switch
diff --git a/drivers/gpu/drm/amd/display/dc/dml/dcn32/dcn32_fpu.h b/drivers/gpu/drm/amd/display/dc/dml/dcn32/dcn32_fpu.h
index ce4c33e64186..b43c45adb7d3 100644
--- a/drivers/gpu/drm/amd/display/dc/dml/dcn32/dcn32_fpu.h
+++ b/drivers/gpu/drm/amd/display/dc/dml/dcn32/dcn32_fpu.h
@@ -70,4 +70,10 @@ void dcn32_calculate_wm_and_dlg_fpu(struct dc *dc, struct dc_state *context,
void dcn32_update_bw_bounding_box_fpu(struct dc *dc, struct clk_bw_params *bw_params);
+int dcn32_find_dummy_latency_index_for_fw_based_mclk_switch(struct dc *dc,
+ struct dc_state *context,
+ display_e2e_pipe_params_st *pipes,
+ int pipe_cnt,
+ int vlevel);
+
#endif
--
2.37.3
