From: Douglas Anderson Date: Mon, 23 Apr 2018 12:49:56 +0200 Subject: drm/bridge: analogix_dp: Properly disable aux chan retries on rockchip MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Git-commit: 7bd0fd9850382252d906bfeb5abfb38aefe28a4f Patch-mainline: v4.18-rc1 References: FATE#326289 FATE#326079 FATE#326049 FATE#322398 FATE#326166 The comments in analogix_dp_init_aux() claim that we're disabling aux channel retries, but then right below it for Rockchip it sets them to 3. If we actually need 3 retries for Rockchip then we could adjust the comment, but it seems more likely that we want the same retry behavior across all platforms. Cc: Stéphane Marchesin Cc: 征增 王 Signed-off-by: Douglas Anderson Signed-off-by: Sean Paul Signed-off-by: Thierry Escande Signed-off-by: Enric Balletbo i Serra Tested-by: Marek Szyprowski Reviewed-by: Archit Taneja Signed-off-by: Andrzej Hajda Link: https://patchwork.freedesktop.org/patch/msgid/20180423105003.9004-21-enric.balletbo@collabora.com Acked-by: Petr Tesarik --- drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c | 15 ++++++++------- 1 file changed, 8 insertions(+), 7 deletions(-) --- a/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c +++ b/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c @@ -481,15 +481,16 @@ void analogix_dp_init_aux(struct analogi analogix_dp_reset_aux(dp); - /* Disable AUX transaction H/W retry */ + /* AUX_BIT_PERIOD_EXPECTED_DELAY doesn't apply to Rockchip IP */ if (dp->plat_data && is_rockchip(dp->plat_data->dev_type)) - reg = AUX_BIT_PERIOD_EXPECTED_DELAY(0) | - AUX_HW_RETRY_COUNT_SEL(3) | - AUX_HW_RETRY_INTERVAL_600_MICROSECONDS; + reg = 0; else - reg = AUX_BIT_PERIOD_EXPECTED_DELAY(3) | - AUX_HW_RETRY_COUNT_SEL(0) | - AUX_HW_RETRY_INTERVAL_600_MICROSECONDS; + reg = AUX_BIT_PERIOD_EXPECTED_DELAY(3); + + /* Disable AUX transaction H/W retry */ + reg |= AUX_HW_RETRY_COUNT_SEL(0) | + AUX_HW_RETRY_INTERVAL_600_MICROSECONDS; + writel(reg, dp->reg_base + ANALOGIX_DP_AUX_HW_RETRY_CTL); /* Receive AUX Channel DEFER commands equal to DEFFER_COUNT*64 */