From: David Galiffi <David.Galiffi@xxxxxxx>
[Why]
Driver is restricting voltage levels if system cannot switch
in vblank.
[How]
Change allow_for_pstate_or_stutter_in_vblank_final from
dm_prefetch_support_uclk_fclk_and_stutter to
dm_prefetch_support_uclk_fclk_and_stutter_if_possible.
Add support for a new registry property,
DalDMLDisallowAlternatePrefetchModes, for easier debugging.
Reviewed-by: Alvin Lee <alvin.lee2@xxxxxxx>
Reviewed-by: Jun Lei <Jun.Lei@xxxxxxx>
Acked-by: Tom Chung <chiahsuan.chung@xxxxxxx>
Signed-off-by: David Galiffi <David.Galiffi@xxxxxxx>
---
drivers/gpu/drm/amd/display/dc/dc.h | 1 +
.../drm/amd/display/dc/dml/dcn32/dcn32_fpu.c | 34 +++++++++++++------
2 files changed, 25 insertions(+), 10 deletions(-)
diff --git a/drivers/gpu/drm/amd/display/dc/dc.h b/drivers/gpu/drm/amd/display/dc/dc.h
index 07feb8551436..86fe4b9f10c2 100644
--- a/drivers/gpu/drm/amd/display/dc/dc.h
+++ b/drivers/gpu/drm/amd/display/dc/dc.h
@@ -788,6 +788,7 @@ struct dc_debug_options {
uint32_t mst_start_top_delay;
uint8_t psr_power_use_phy_fsm;
enum dml_hostvm_override_opts dml_hostvm_override;
+ bool dml_disallow_alternate_prefetch_modes;
bool use_legacy_soc_bb_mechanism;
bool exit_idle_opt_for_cursor_updates;
bool enable_single_display_2to1_odm_policy;
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 988e28a8e90e..85ecd94e2a4a 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
@@ -986,9 +986,15 @@ static void dcn32_full_validate_bw_helper(struct dc *dc,
* DML favors voltage over p-state, but we're more interested in
* supporting p-state over voltage. We can't support p-state in
* prefetch mode > 0 so try capping the prefetch mode to start.
+ * Override present for testing.
*/
- context->bw_ctx.dml.soc.allow_for_pstate_or_stutter_in_vblank_final =
+ if (dc->debug.dml_disallow_alternate_prefetch_modes)
+ context->bw_ctx.dml.soc.allow_for_pstate_or_stutter_in_vblank_final =
dm_prefetch_support_uclk_fclk_and_stutter;
+ else
+ context->bw_ctx.dml.soc.allow_for_pstate_or_stutter_in_vblank_final =
+ dm_prefetch_support_uclk_fclk_and_stutter_if_possible;
+
*vlevel = dml_get_voltage_level(&context->bw_ctx.dml, pipes, *pipe_cnt);
/* This may adjust vlevel and maxMpcComb */
if (*vlevel < context->bw_ctx.dml.soc.num_states)
@@ -1017,7 +1023,9 @@ static void dcn32_full_validate_bw_helper(struct dc *dc,
* will not allow for switch in VBLANK. The DRR display must have it's VBLANK stretched
* enough to support MCLK switching.
*/
- if (*vlevel == context->bw_ctx.dml.soc.num_states) {
+ if (*vlevel == context->bw_ctx.dml.soc.num_states &&
+ 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;
/* There are params (such as FabricClock) that need to be recalculated
@@ -1347,7 +1355,8 @@ bool dcn32_internal_validate_bw(struct dc *dc,
int split[MAX_PIPES] = { 0 };
bool merge[MAX_PIPES] = { false };
bool newly_split[MAX_PIPES] = { false };
- int pipe_cnt, i, pipe_idx, vlevel;
+ int pipe_cnt, i, pipe_idx;
+ int vlevel = context->bw_ctx.dml.soc.num_states;
struct vba_vars_st *vba = &context->bw_ctx.dml.vba;
dc_assert_fp_enabled();
@@ -1376,17 +1385,22 @@ bool dcn32_internal_validate_bw(struct dc *dc,
DC_FP_END();
}
- if (fast_validate || vlevel == context->bw_ctx.dml.soc.num_states ||
- vba->DRAMClockChangeSupport[vlevel][vba->maxMpcComb] == dm_dram_clock_change_unsupported) {
+ if (fast_validate ||
+ dc->debug.dml_disallow_alternate_prefetch_modes &&
+ (vlevel == context->bw_ctx.dml.soc.num_states ||
+ vba->DRAMClockChangeSupport[vlevel][vba->maxMpcComb] == dm_dram_clock_change_unsupported)) {
/*
- * If mode is unsupported or there's still no p-state support then
- * fall back to favoring voltage.
+ * If dml_disallow_alternate_prefetch_modes is false, then we have already
+ * tried alternate prefetch modes during full validation.
+ *
+ * If mode is unsupported or there is no p-state support, then
+ * fall back to favouring voltage.
*
- * If Prefetch mode 0 failed for this config, or passed with Max UCLK, try if
- * supported with Prefetch mode 1 (dm_prefetch_support_fclk_and_stutter == 2)
+ * If Prefetch mode 0 failed for this config, or passed with Max UCLK, then try
+ * to support with Prefetch mode 1 (dm_prefetch_support_fclk_and_stutter == 2)
*/
context->bw_ctx.dml.soc.allow_for_pstate_or_stutter_in_vblank_final =
- dm_prefetch_support_fclk_and_stutter;
+ dm_prefetch_support_fclk_and_stutter;
vlevel = dml_get_voltage_level(&context->bw_ctx.dml, pipes, pipe_cnt);
--
2.25.1
