From ff79cbdccea94935ff9d2111458e439e28c86e74 Mon Sep 17 00:00:00 2001 From: Bhawanpreet Lakha Date: Mon, 2 Oct 2017 13:40:02 -0400 Subject: [PATCH] drm/amd/display: increase pstate wait timeout For linux it takes longer than 40us so increasing it to 200us. Also added debug prints regarding the change Signed-off-by: Bhawanpreet Lakha Reviewed-by: Tony Cheng Acked-by: Harry Wentland Signed-off-by: Alex Deucher --- .../amd/display/dc/dcn10/dcn10_hw_sequencer.c | 20 ++++++++++++++++--- 1 file changed, 17 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_hw_sequencer.c b/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_hw_sequencer.c index db774b3c3721..012ba7c9ca8d 100644 --- a/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_hw_sequencer.c +++ b/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_hw_sequencer.c @@ -245,8 +245,13 @@ static void verify_allow_pstate_change_high( { /* pstate latency is ~20us so if we wait over 40us and pstate allow * still not asserted, we are probably stuck and going to hang + * + * TODO: Figure out why it takes ~100us on linux + * pstate takes around ~100us on linux. Unknown currently as to + * why it takes that long on linux */ - static unsigned int pstate_wait_timeout_us = 40; + static unsigned int pstate_wait_timeout_us = 200; + static unsigned int pstate_wait_expected_timeout_us = 40; static unsigned int max_sampled_pstate_wait_us; /* data collection */ static bool forced_pstate_allow; /* help with revert wa */ static bool should_log_hw_state; /* prevent hw state log by default */ @@ -293,9 +298,15 @@ static void verify_allow_pstate_change_high( for (i = 0; i < pstate_wait_timeout_us; i++) { debug_data = REG_READ(DCHUBBUB_TEST_DEBUG_DATA); - if (debug_data & (1 << 30)) - return; + if (debug_data & (1 << 30)) { + + if (i > pstate_wait_expected_timeout_us) + dm_logger_write(hws->ctx->logger, LOG_WARNING, + "pstate took longer than expected ~%dus", + i); + return; + } if (max_sampled_pstate_wait_us < i) max_sampled_pstate_wait_us = i; @@ -314,6 +325,9 @@ static void verify_allow_pstate_change_high( dcn10_log_hw_state(hws->ctx->dc); } + dm_logger_write(hws->ctx->logger, LOG_WARNING, + "pstate TEST_DEBUG_DATA: 0x%X", + debug_data); BREAK_TO_DEBUGGER(); } -- 2.30.2