[PATCH 08/22] drm/amd/display: Use dummy pstate latency for subvp when needed on dcn32
brichang
Brian.Chang at amd.com
Fri Nov 18 12:59:21 UTC 2022
From: Dillon Varone <Dillon.Varone at amd.com>
[WHY?]
Prefetch is not budgetting time for dummy pstate when using subvp and low uclk.
[HOW?]
Override fclk change latency to use dummy pstate latency when calculating
prefetch schedule for subvp configs with low uclk.
Reviewed-by: Jun Lei <Jun.Lei at amd.com>
Acked-by: Brian Chang <Brian.Chang at amd.com>
Signed-off-by: Dillon Varone <Dillon.Varone at amd.com>
---
.../drm/amd/display/dc/dml/dcn32/dcn32_fpu.c | 61 +++++++++++++++----
1 file changed, 49 insertions(+), 12 deletions(-)
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 61dbfa95eaa4..c881c523c37a 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
@@ -256,16 +256,24 @@ int dcn32_find_dummy_latency_index_for_fw_based_mclk_switch(struct dc *dc,
int vlevel)
{
const int max_latency_table_entries = 4;
- const struct vba_vars_st *vba = &context->bw_ctx.dml.vba;
+ struct vba_vars_st *vba = &context->bw_ctx.dml.vba;
int dummy_latency_index = 0;
+ enum clock_change_support temp_clock_change_support = vba->DRAMClockChangeSupport[vlevel][context->bw_ctx.dml.vba.maxMpcComb];
dc_assert_fp_enabled();
while (dummy_latency_index < max_latency_table_entries) {
+ if (temp_clock_change_support != dm_dram_clock_change_unsupported)
+ vba->DRAMClockChangeSupport[vlevel][context->bw_ctx.dml.vba.maxMpcComb] = temp_clock_change_support;
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);
+ /* for subvp + DRR case, if subvp pipes are still present we support pstate */
+ if (vba->DRAMClockChangeSupport[vlevel][vba->maxMpcComb] == dm_dram_clock_change_unsupported &&
+ dcn32_subvp_in_use(dc, context))
+ vba->DRAMClockChangeSupport[vlevel][context->bw_ctx.dml.vba.maxMpcComb] = temp_clock_change_support;
+
if (vlevel < context->bw_ctx.dml.vba.soc.num_states &&
vba->DRAMClockChangeSupport[vlevel][vba->maxMpcComb] != dm_dram_clock_change_unsupported)
break;
@@ -1141,7 +1149,7 @@ static void dcn32_full_validate_bw_helper(struct dc *dc,
context->bw_ctx.dml.soc.allow_for_pstate_or_stutter_in_vblank_final ==
dm_prefetch_support_uclk_fclk_and_stutter) {
context->bw_ctx.dml.soc.allow_for_pstate_or_stutter_in_vblank_final =
- dm_prefetch_support_stutter;
+ dm_prefetch_support_fclk_and_stutter;
/* There are params (such as FabricClock) that need to be recalculated
* after validation fails (otherwise it will be 0). Calculation for
* phantom vactive requires call into DML, so we must ensure all the
@@ -1816,14 +1824,38 @@ void dcn32_calculate_wm_and_dlg_fpu(struct dc *dc, struct dc_state *context,
unsigned int dummy_latency_index = 0;
int maxMpcComb = context->bw_ctx.dml.vba.maxMpcComb;
unsigned int min_dram_speed_mts = context->bw_ctx.dml.vba.DRAMSpeed;
+ bool subvp_in_use = dcn32_subvp_in_use(dc, context);
unsigned int min_dram_speed_mts_margin;
+ bool need_fclk_lat_as_dummy = false;
+ bool is_subvp_p_drr = true;
dc_assert_fp_enabled();
- // Override DRAMClockChangeSupport for SubVP + DRR case where the DRR cannot switch without stretching it's VBLANK
- if (!pstate_en && dcn32_subvp_in_use(dc, context)) {
- context->bw_ctx.dml.vba.DRAMClockChangeSupport[vlevel][context->bw_ctx.dml.vba.maxMpcComb] = dm_dram_clock_change_vblank_w_mall_sub_vp;
- pstate_en = true;
+ /* need to find dummy latency index for subvp */
+ if (subvp_in_use) {
+ /* Override DRAMClockChangeSupport for SubVP + DRR case where the DRR cannot switch without stretching it's VBLANK */
+ if (!pstate_en) {
+ context->bw_ctx.dml.vba.DRAMClockChangeSupport[vlevel][context->bw_ctx.dml.vba.maxMpcComb] = dm_dram_clock_change_vblank_w_mall_sub_vp;
+ pstate_en = true;
+ is_subvp_p_drr = true;
+ }
+ dummy_latency_index = dcn32_find_dummy_latency_index_for_fw_based_mclk_switch(dc,
+ context, pipes, pipe_cnt, vlevel);
+
+ /* For DCN32/321 need to validate with fclk pstate change latency equal to dummy so prefetch is
+ * scheduled correctly to account for dummy pstate.
+ */
+ if (context->bw_ctx.dml.soc.fclk_change_latency_us < dc->clk_mgr->bw_params->dummy_pstate_table[dummy_latency_index].dummy_pstate_latency_us) {
+ need_fclk_lat_as_dummy = true;
+ context->bw_ctx.dml.soc.fclk_change_latency_us =
+ dc->clk_mgr->bw_params->dummy_pstate_table[dummy_latency_index].dummy_pstate_latency_us;
+ }
+ context->bw_ctx.dml.soc.dram_clock_change_latency_us =
+ dc->clk_mgr->bw_params->wm_table.nv_entries[WM_A].dml_input.pstate_latency_us;
+ dcn32_internal_validate_bw(dc, context, pipes, &pipe_cnt, &vlevel, false);
+ if (is_subvp_p_drr) {
+ context->bw_ctx.dml.vba.DRAMClockChangeSupport[vlevel][context->bw_ctx.dml.vba.maxMpcComb] = dm_dram_clock_change_vblank_w_mall_sub_vp;
+ }
}
context->bw_ctx.bw.dcn.clk.fw_based_mclk_switching = false;
@@ -1847,9 +1879,11 @@ void dcn32_calculate_wm_and_dlg_fpu(struct dc *dc, struct dc_state *context,
/* For DCN32/321 need to validate with fclk pstate change latency equal to dummy so
* prefetch is scheduled correctly to account for dummy pstate.
*/
- if (dummy_latency_index == 0)
+ if (context->bw_ctx.dml.soc.fclk_change_latency_us < dc->clk_mgr->bw_params->dummy_pstate_table[dummy_latency_index].dummy_pstate_latency_us) {
+ need_fclk_lat_as_dummy = true;
context->bw_ctx.dml.soc.fclk_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);
maxMpcComb = context->bw_ctx.dml.vba.maxMpcComb;
dcfclk_from_fw_based_mclk_switching = context->bw_ctx.dml.vba.DCFCLKState[vlevel][context->bw_ctx.dml.vba.maxMpcComb];
@@ -1957,7 +1991,7 @@ void dcn32_calculate_wm_and_dlg_fpu(struct dc *dc, struct dc_state *context,
dc->clk_mgr->bw_params->clk_table.entries[min_dram_speed_mts_offset].memclk_mhz * 16;
}
- if (!context->bw_ctx.bw.dcn.clk.fw_based_mclk_switching) {
+ if (!context->bw_ctx.bw.dcn.clk.fw_based_mclk_switching && !subvp_in_use) {
/* find largest table entry that is lower than dram speed,
* but lower than DPM0 still uses DPM0
*/
@@ -2037,7 +2071,8 @@ void dcn32_calculate_wm_and_dlg_fpu(struct dc *dc, struct dc_state *context,
context->perf_params.stutter_period_us = context->bw_ctx.dml.vba.StutterPeriod;
- if (context->bw_ctx.bw.dcn.clk.fw_based_mclk_switching && dummy_latency_index == 0)
+ /* for proper prefetch calculations, if dummy lat > fclk lat, use fclk lat = dummy lat */
+ if (need_fclk_lat_as_dummy)
context->bw_ctx.dml.soc.fclk_change_latency_us =
dc->clk_mgr->bw_params->dummy_pstate_table[dummy_latency_index].dummy_pstate_latency_us;
@@ -2050,10 +2085,12 @@ void dcn32_calculate_wm_and_dlg_fpu(struct dc *dc, struct dc_state *context,
if (context->bw_ctx.bw.dcn.clk.fw_based_mclk_switching) {
dcn30_setup_mclk_switch_using_fw_based_vblank_stretch(dc, context);
- if (dummy_latency_index == 0)
- context->bw_ctx.dml.soc.fclk_change_latency_us =
- dc->clk_mgr->bw_params->wm_table.nv_entries[WM_A].dml_input.fclk_change_latency_us;
}
+
+ /* revert fclk lat changes if required */
+ if (need_fclk_lat_as_dummy)
+ context->bw_ctx.dml.soc.fclk_change_latency_us =
+ dc->clk_mgr->bw_params->wm_table.nv_entries[WM_A].dml_input.fclk_change_latency_us;
}
static void dcn32_get_optimal_dcfclk_fclk_for_uclk(unsigned int uclk_mts,
--
2.25.1
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