From: Wesley Chalmers <Wesley.Chalmers@xxxxxxx>
[WHY]
It is possible to commit state multiple times in rapid succession with
FAMS enabled; if each of these commits were to set optimized_required,
then the user may see latency.
[HOW]
fw_based_mclk_switching is currently not used in dc->clk_mgr; use it
to track whether the current state has FAMS enabled;
if it has, then do not disable FAMS in prepare_bandwidth, and do not set
optimized_required.
Reviewed-by: Rodrigo Siqueira <Rodrigo.Siqueira@xxxxxxx>
Signed-off-by: Wesley Chalmers <Wesley.Chalmers@xxxxxxx>
---
.../drm/amd/display/dc/dcn20/dcn20_hwseq.c | 3 +++
.../drm/amd/display/dc/dcn30/dcn30_hwseq.c | 22 ++++++++++++++++---
2 files changed, 22 insertions(+), 3 deletions(-)
diff --git a/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_hwseq.c b/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_hwseq.c
index 6ce10fd4bb1a..422fbf79da64 100644
--- a/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_hwseq.c
+++ b/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_hwseq.c
@@ -2117,6 +2117,9 @@ void dcn20_optimize_bandwidth(
dc_dmub_srv_p_state_delegate(dc,
true, context);
context->bw_ctx.bw.dcn.clk.p_state_change_support = true;
+ dc->clk_mgr->clks.fw_based_mclk_switching = true;
+ } else {
+ dc->clk_mgr->clks.fw_based_mclk_switching = false;
}
dc->clk_mgr->funcs->update_clocks(
diff --git a/drivers/gpu/drm/amd/display/dc/dcn30/dcn30_hwseq.c b/drivers/gpu/drm/amd/display/dc/dcn30/dcn30_hwseq.c
index 0411867654dd..8263a07f265f 100644
--- a/drivers/gpu/drm/amd/display/dc/dcn30/dcn30_hwseq.c
+++ b/drivers/gpu/drm/amd/display/dc/dcn30/dcn30_hwseq.c
@@ -983,9 +983,13 @@ void dcn30_set_disp_pattern_generator(const struct dc *dc,
}
void dcn30_prepare_bandwidth(struct dc *dc,
- struct dc_state *context)
+ struct dc_state *context)
{
- if (context->bw_ctx.bw.dcn.clk.fw_based_mclk_switching) {
+ bool p_state_change_support = context->bw_ctx.bw.dcn.clk.p_state_change_support;
+ /* Any transition into an FPO config should disable MCLK switching first to avoid
+ * driver and FW P-State synchronization issues.
+ */
+ if (context->bw_ctx.bw.dcn.clk.fw_based_mclk_switching || dc->clk_mgr->clks.fw_based_mclk_switching) {
dc->optimized_required = true;
context->bw_ctx.bw.dcn.clk.p_state_change_support = false;
}
@@ -996,7 +1000,19 @@ void dcn30_prepare_bandwidth(struct dc *dc,
dc->clk_mgr->funcs->set_max_memclk(dc->clk_mgr, dc->clk_mgr->bw_params->clk_table.entries[dc->clk_mgr->bw_params->clk_table.num_entries - 1].memclk_mhz);
dcn20_prepare_bandwidth(dc, context);
+ /*
+ * enabled -> enabled: do not disable
+ * enabled -> disabled: disable
+ * disabled -> enabled: don't care
+ * disabled -> disabled: don't care
+ */
+ if (!context->bw_ctx.bw.dcn.clk.fw_based_mclk_switching)
+ dc_dmub_srv_p_state_delegate(dc, false, context);
- dc_dmub_srv_p_state_delegate(dc, false, context);
+ if (context->bw_ctx.bw.dcn.clk.fw_based_mclk_switching || dc->clk_mgr->clks.fw_based_mclk_switching) {
+ /* After disabling P-State, restore the original value to ensure we get the correct P-State
+ * on the next optimize. */
+ context->bw_ctx.bw.dcn.clk.p_state_change_support = p_state_change_support;
+ }
}
--
2.34.1
