lkml.org 
[lkml]   [2021]   [Aug]   [2]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[PATCH 5.13 025/104] drm/amd/display: ensure dentist display clock update finished in DCN20
    Date
    From: Dale Zhao <dale.zhao@amd.com>

    commit b53e041d8e4308f7324999398aec092dbcb130f5 upstream.

    [Why]
    We don't check DENTIST_DISPCLK_CHG_DONE to ensure dentist
    display clockis updated to target value. In some scenarios with large
    display clock margin, it will deliver unfinished display clock and cause
    issues like display black screen.

    [How]
    Checking DENTIST_DISPCLK_CHG_DONE to ensure display clock
    has been update to target value before driver do other clock related
    actions.

    Reviewed-by: Cyr Aric <aric.cyr@amd.com>
    Acked-by: Solomon Chiu <solomon.chiu@amd.com>
    Signed-off-by: Dale Zhao <dale.zhao@amd.com>
    Tested-by: Daniel Wheeler <daniel.wheeler@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>
    ---
    drivers/gpu/drm/amd/display/dc/clk_mgr/dcn20/dcn20_clk_mgr.c | 2 +-
    1 file changed, 1 insertion(+), 1 deletion(-)

    --- a/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn20/dcn20_clk_mgr.c
    +++ b/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn20/dcn20_clk_mgr.c
    @@ -135,7 +135,7 @@ void dcn20_update_clocks_update_dentist(

    REG_UPDATE(DENTIST_DISPCLK_CNTL,
    DENTIST_DISPCLK_WDIVIDER, dispclk_wdivider);
    -// REG_WAIT(DENTIST_DISPCLK_CNTL, DENTIST_DISPCLK_CHG_DONE, 1, 5, 100);
    + REG_WAIT(DENTIST_DISPCLK_CNTL, DENTIST_DISPCLK_CHG_DONE, 1, 50, 1000);
    REG_UPDATE(DENTIST_DISPCLK_CNTL,
    DENTIST_DPPCLK_WDIVIDER, dppclk_wdivider);
    REG_WAIT(DENTIST_DISPCLK_CNTL, DENTIST_DPPCLK_CHG_DONE, 1, 5, 100);

    \
     
     \ /
      Last update: 2021-08-02 16:13    [W:3.907 / U:0.140 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site