drm/amd/display: early return when pipe_cnt is 0 in bw validation

[Why]
Unintentionally introduced behaviour change from previous refactor,
which causes clks to be 0 in no stream cases, which will cause
divide by 0.

[How]
Skip calculation of clocks when no stream. Which is the same as old
behaviour.

Signed-off-by: Eric Yang <Eric.Yang2@amd.com>
Reviewed-by: Tony Cheng <tong.cheng@amd.com>
Acked-by: Leo Li <sunpeng.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --git a/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_resource.c b/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_resource.c
index b57c4206187041316d517dc9c532333feb5ba6b7..ae2545fb8eceaeaf65f0d58bd31b1d668080a941 100644 (file)
--- a/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_resource.c
+++ b/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_resource.c
@@ -2022,6 +2022,7 @@ bool dcn20_fast_validate_bw(
                struct dc *dc,
                struct dc_state *context,
                display_e2e_pipe_params_st *pipes,
+               int *pipe_cnt_out,
                int *pipe_split_from,
                int *vlevel_out)
 {
@@ -2074,6 +2075,8 @@ bool dcn20_fast_validate_bw(
                pipe_cnt = dcn20_populate_dml_pipes_from_context(dc,
                        &context->res_ctx, pipes);
 
+       *pipe_cnt_out = pipe_cnt;
+
        if (!pipe_cnt) {
                out = true;
                goto validate_out;
@@ -2434,7 +2437,10 @@ bool dcn20_validate_bandwidth(struct dc *dc, struct dc_state *context,
 
        BW_VAL_TRACE_COUNT();
 
-       out = dcn20_fast_validate_bw(dc, context, pipes, pipe_split_from, &vlevel);
+       out = dcn20_fast_validate_bw(dc, context, pipes, &pipe_cnt, pipe_split_from, &vlevel);
+
+       if (pipe_cnt == 0)
+               goto validate_out;
 
        if (!out)
                goto validate_fail;

diff --git a/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_resource.h b/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_resource.h
index 2b3692e0c48d903c920396cdd18576c8e4315c3e..44f95aa0d61e09ddde99baa8c318ffa743e0f431 100644 (file)
--- a/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_resource.h
+++ b/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_resource.h
@@ -120,6 +120,7 @@ bool dcn20_fast_validate_bw(
                struct dc *dc,
                struct dc_state *context,
                display_e2e_pipe_params_st *pipes,
+               int *pipe_cnt_out,
                int *pipe_split_from,
                int *vlevel_out);
 void dcn20_calculate_dlg_params(