drm/amd/display: Check for null fclk voltage when parsing clock table

commit 72f5b5a308c744573fdbc6c78202c52196d2c162 upstream.

[WHY]
In cases where a clock table is malformed such that fclk entries have
frequencies but not voltages listed, we don't catch the error and set
clocks to 0 instead of using hardcoded values as we should.

[HOW]
Add check for clock tables fclk entry's voltage as well

Signed-off-by: Michael Strauss <michael.strauss@amd.com>
Reviewed-by: Eric Yang <eric.yang2@amd.com>
Acked-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn21/rn_clk_mgr.c b/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn21/rn_clk_mgr.c
index 9ef3f7b91a1d08aed184038dd6ff82e566bb6a6b..abdf29afa2f229038fee15cc827b65efe8684ec4 100644 (file)
--- a/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn21/rn_clk_mgr.c
+++ b/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn21/rn_clk_mgr.c
@@ -643,7 +643,7 @@ static void rn_clk_mgr_helper_populate_bw_params(struct clk_bw_params *bw_params
        /* Find lowest DPM, FCLK is filled in reverse order*/
 
        for (i = PP_SMU_NUM_FCLK_DPM_LEVELS - 1; i >= 0; i--) {
-               if (clock_table->FClocks[i].Freq != 0) {
+               if (clock_table->FClocks[i].Freq != 0 && clock_table->FClocks[i].Vol != 0) {
                        j = i;
                        break;
                }