drm/amd/display: option to maximize lb usage

experimental change for testing if max line buffer result in better stutter efficiency

for 1080p, LB can hold up to 9 line at 10bpcc, potentially add 10 line time of
latency hiding.

Signed-off-by: Tony Cheng <tony.cheng@amd.com>
Reviewed-by: Yongqiang Sun <yongqiang.sun@amd.com>
Acked-by: Harry Wentland <Harry.Wentland@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --git a/drivers/gpu/drm/amd/display/dc/dc.h b/drivers/gpu/drm/amd/display/dc/dc.h
index d7afbcf..427ccbc 100644 (file)
--- a/drivers/gpu/drm/amd/display/dc/dc.h
+++ b/drivers/gpu/drm/amd/display/dc/dc.h
@@ -181,15 +181,19 @@ struct dc_debug {
        bool timing_trace;
        bool clock_trace;
        bool validation_trace;
+
+       /* stutter efficiency related */
        bool disable_stutter;
+       bool use_max_lb;
        enum dcc_option disable_dcc;
+       enum pipe_split_policy pipe_split_policy;
+       bool force_single_disp_pipe_split;
+
        bool disable_dfs_bypass;
        bool disable_dpp_power_gate;
        bool disable_hubp_power_gate;
        bool disable_pplib_wm_range;
        bool use_dml_wm;
-       enum pipe_split_policy pipe_split_policy;
-       bool force_single_disp_pipe_split;
        unsigned int min_disp_clk_khz;
        int sr_exit_time_dpm0_ns;
        int sr_enter_plus_exit_time_dpm0_ns;

diff --git a/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_dpp_dscl.c b/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_dpp_dscl.c
index 82b8887..fa2ab99 100644 (file)
--- a/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_dpp_dscl.c
+++ b/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_dpp_dscl.c
@@ -507,6 +507,9 @@ static enum lb_memory_config find_lb_memory_config(struct dcn10_dpp *xfm,
 {
        enum lb_memory_config mem_cfg = LB_MEMORY_CONFIG_0;
 
+       if (xfm->base.ctx->dc->debug.use_max_lb)
+               return mem_cfg;
+
        if (xfm->tf_mask->PIXEL_DEPTH) {
                mem_cfg = dpp10_find_lb_memory_config(scl_data);
        }