6.6-stable review patch. If anyone has any objections, please let me know.
------------------
From: Samson Tam samson.tam@amd.com
[ Upstream commit 79f3f1b66753b3a3a269d73676bf50987921f267 ]
[Why] Helper function calculates num_ways using 32-bit. But is returned as 8-bit. If num_ways exceeds 8-bit, then it reports back the incorrect num_ways and erroneously uses MALL when it should not
[How] Make returned value 32-bit and convert after it checks against caps.cache_num_ways, which is under 8-bit
Reviewed-by: Alvin Lee alvin.lee2@amd.com Acked-by: Roman Li roman.li@amd.com Signed-off-by: Samson Tam samson.tam@amd.com Tested-by: Daniel Wheeler daniel.wheeler@amd.com Signed-off-by: Alex Deucher alexander.deucher@amd.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/amd/display/dc/dcn32/dcn32_hwseq.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-)
diff --git a/drivers/gpu/drm/amd/display/dc/dcn32/dcn32_hwseq.c b/drivers/gpu/drm/amd/display/dc/dcn32/dcn32_hwseq.c index 018376146d977..be59e1c02f8aa 100644 --- a/drivers/gpu/drm/amd/display/dc/dcn32/dcn32_hwseq.c +++ b/drivers/gpu/drm/amd/display/dc/dcn32/dcn32_hwseq.c @@ -214,7 +214,7 @@ static bool dcn32_check_no_memory_request_for_cab(struct dc *dc) static uint32_t dcn32_calculate_cab_allocation(struct dc *dc, struct dc_state *ctx) { int i; - uint8_t num_ways = 0; + uint32_t num_ways = 0; uint32_t mall_ss_size_bytes = 0;
mall_ss_size_bytes = ctx->bw_ctx.bw.dcn.mall_ss_size_bytes; @@ -244,7 +244,8 @@ static uint32_t dcn32_calculate_cab_allocation(struct dc *dc, struct dc_state *c bool dcn32_apply_idle_power_optimizations(struct dc *dc, bool enable) { union dmub_rb_cmd cmd; - uint8_t ways, i; + uint8_t i; + uint32_t ways; int j; bool mall_ss_unsupported = false; struct dc_plane_state *plane = NULL; @@ -304,7 +305,7 @@ bool dcn32_apply_idle_power_optimizations(struct dc *dc, bool enable) cmd.cab.header.type = DMUB_CMD__CAB_FOR_SS; cmd.cab.header.sub_type = DMUB_CMD__CAB_DCN_SS_FIT_IN_CAB; cmd.cab.header.payload_bytes = sizeof(cmd.cab) - sizeof(cmd.cab.header); - cmd.cab.cab_alloc_ways = ways; + cmd.cab.cab_alloc_ways = (uint8_t)ways;
dm_execute_dmub_cmd(dc->ctx, &cmd, DM_DMUB_WAIT_TYPE_NO_WAIT);