From: Jun Lei Date: Wed, 24 Oct 2018 15:39:55 +0000 (-0400) Subject: drm/amd/display: clear underflow on optc unblank X-Git-Tag: v5.15~7216^2~13^2~80 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=3ce224421b66c740bb2902e69f0dd1163373842a;p=platform%2Fkernel%2Flinux-starfive.git drm/amd/display: clear underflow on optc unblank [why] Underflow is asserted due to some timing condition which does not actually result in visible underflow (i.e. it occurs while blanked). [how] Force clear underflow occured bit whenver we unblank. Signed-off-by: Jun Lei Reviewed-by: Tony Cheng Acked-by: Aric Cyr Acked-by: Bhawanpreet Lakha Signed-off-by: Alex Deucher --- diff --git a/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_optc.c b/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_optc.c index 7c76f40..7c13861 100644 --- a/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_optc.c +++ b/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_optc.c @@ -359,20 +359,19 @@ void optc1_set_blank_data_double_buffer(struct timing_generator *optc, bool enab static void optc1_unblank_crtc(struct timing_generator *optc) { struct optc *optc1 = DCN10TG_FROM_TG(optc); - uint32_t vertical_interrupt_enable = 0; - - REG_GET(OTG_VERTICAL_INTERRUPT2_CONTROL, - OTG_VERTICAL_INTERRUPT2_INT_ENABLE, &vertical_interrupt_enable); - - /* temporary work around for vertical interrupt, once vertical interrupt enabled, - * this check will be removed. - */ - if (vertical_interrupt_enable) - optc1_set_blank_data_double_buffer(optc, true); REG_UPDATE_2(OTG_BLANK_CONTROL, OTG_BLANK_DATA_EN, 0, OTG_BLANK_DE_MODE, 0); + + /* W/A for automated testing + * Automated testing will fail underflow test as there + * sporadic underflows which occur during the optc blank + * sequence. As a w/a, clear underflow on unblank. + * This prevents the failure, but will not mask actual + * underflow that affect real use cases. + */ + optc1_clear_optc_underflow(optc); } /**