From: Wesley Chalmers <[email protected]> [ Upstream commit 6bd0a112ec129615d23aa5d8d3dd0be0243989aa ]
[WHY] When changing DPP global ref clock, DTO adjustments must take effect immediately, or else underflow may occur. It appears the original decision to double-buffer DTO adjustments was made to prevent underflows that occur when raising DPP ref clock (which is not double-buffered), but that same decision causes similar issues when lowering DPP global ref clock. The better solution is to order the adjustments according to whether clocks are being raised or lowered. Signed-off-by: Wesley Chalmers <[email protected]> Reviewed-by: Dmytro Laktyushkin <[email protected]> Acked-by: Anthony Koo <[email protected]> Acked-by: Leo Li <[email protected]> Signed-off-by: Alex Deucher <[email protected]> Signed-off-by: Sasha Levin <[email protected]> --- .../gpu/drm/amd/display/dc/dcn20/dcn20_dccg.c | 26 ------------------- 1 file changed, 26 deletions(-) diff --git a/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_dccg.c b/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_dccg.c index 16476ed255363..2064366322755 100644 --- a/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_dccg.c +++ b/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_dccg.c @@ -119,32 +119,6 @@ void dccg2_get_dccg_ref_freq(struct dccg *dccg, void dccg2_init(struct dccg *dccg) { - struct dcn_dccg *dccg_dcn = TO_DCN_DCCG(dccg); - - // Fallthrough intentional to program all available dpp_dto's - switch (dccg_dcn->base.ctx->dc->res_pool->pipe_count) { - case 6: - REG_UPDATE(DPPCLK_DTO_CTRL, DPPCLK_DTO_DB_EN[5], 1); - /* Fall through */ - case 5: - REG_UPDATE(DPPCLK_DTO_CTRL, DPPCLK_DTO_DB_EN[4], 1); - /* Fall through */ - case 4: - REG_UPDATE(DPPCLK_DTO_CTRL, DPPCLK_DTO_DB_EN[3], 1); - /* Fall through */ - case 3: - REG_UPDATE(DPPCLK_DTO_CTRL, DPPCLK_DTO_DB_EN[2], 1); - /* Fall through */ - case 2: - REG_UPDATE(DPPCLK_DTO_CTRL, DPPCLK_DTO_DB_EN[1], 1); - /* Fall through */ - case 1: - REG_UPDATE(DPPCLK_DTO_CTRL, DPPCLK_DTO_DB_EN[0], 1); - break; - default: - ASSERT(false); - break; - } } static const struct dccg_funcs dccg2_funcs = { -- 2.25.1
