From 691456f622a96b4e90e7798a671c7753d924375f Mon Sep 17 00:00:00 2001 From: Maxime Ripard Date: Thu, 3 Sep 2020 10:01:43 +0200 Subject: [PATCH] drm/vc4: hdmi: Always recenter the HDMI FIFO In order to avoid a pixel getting stuck in an unflushable FIFO, we need to recenter the FIFO every time we're doing a modeset and not only if we're connected to an HDMI monitor. Signed-off-by: Maxime Ripard Tested-by: Chanwoo Choi Tested-by: Hoegeun Kwon Tested-by: Stefan Wahren Reviewed-by: Dave Stevenson Link: https://patchwork.freedesktop.org/patch/msgid/b3faaf05ac6c4d3c364d28fa441571eb85903269.1599120059.git-series.maxime@cerno.tech --- drivers/gpu/drm/vc4/vc4_hdmi.c | 46 ++++++++++++++++++++++++------------------ 1 file changed, 26 insertions(+), 20 deletions(-) diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.c b/drivers/gpu/drm/vc4/vc4_hdmi.c index 3c7862a..c9eae53 100644 --- a/drivers/gpu/drm/vc4/vc4_hdmi.c +++ b/drivers/gpu/drm/vc4/vc4_hdmi.c @@ -425,6 +425,30 @@ static void vc4_hdmi_set_timings(struct vc4_hdmi *vc4_hdmi, (hsync_pos ? 0 : VC4_HD_VID_CTL_HSYNC_LOW)); } +static void vc4_hdmi_recenter_fifo(struct vc4_hdmi *vc4_hdmi) +{ + u32 drift; + int ret; + + drift = HDMI_READ(HDMI_FIFO_CTL); + drift &= VC4_HDMI_FIFO_VALID_WRITE_MASK; + + HDMI_WRITE(HDMI_FIFO_CTL, + drift & ~VC4_HDMI_FIFO_CTL_RECENTER); + HDMI_WRITE(HDMI_FIFO_CTL, + drift | VC4_HDMI_FIFO_CTL_RECENTER); + usleep_range(1000, 1100); + HDMI_WRITE(HDMI_FIFO_CTL, + drift & ~VC4_HDMI_FIFO_CTL_RECENTER); + HDMI_WRITE(HDMI_FIFO_CTL, + drift | VC4_HDMI_FIFO_CTL_RECENTER); + + ret = wait_for(HDMI_READ(HDMI_FIFO_CTL) & + VC4_HDMI_FIFO_CTL_RECENTER_DONE, 1); + WARN_ONCE(ret, "Timeout waiting for " + "VC4_HDMI_FIFO_CTL_RECENTER_DONE"); +} + static void vc4_hdmi_encoder_enable(struct drm_encoder *encoder) { struct drm_display_mode *mode = &encoder->crtc->state->adjusted_mode; @@ -543,8 +567,6 @@ static void vc4_hdmi_encoder_enable(struct drm_encoder *encoder) } if (vc4_encoder->hdmi_monitor) { - u32 drift; - WARN_ON(!(HDMI_READ(HDMI_SCHEDULER_CONTROL) & VC4_HDMI_SCHEDULER_CONTROL_HDMI_ACTIVE)); HDMI_WRITE(HDMI_SCHEDULER_CONTROL, @@ -555,25 +577,9 @@ static void vc4_hdmi_encoder_enable(struct drm_encoder *encoder) VC4_HDMI_RAM_PACKET_ENABLE); vc4_hdmi_set_infoframes(encoder); - - drift = HDMI_READ(HDMI_FIFO_CTL); - drift &= VC4_HDMI_FIFO_VALID_WRITE_MASK; - - HDMI_WRITE(HDMI_FIFO_CTL, - drift & ~VC4_HDMI_FIFO_CTL_RECENTER); - HDMI_WRITE(HDMI_FIFO_CTL, - drift | VC4_HDMI_FIFO_CTL_RECENTER); - usleep_range(1000, 1100); - HDMI_WRITE(HDMI_FIFO_CTL, - drift & ~VC4_HDMI_FIFO_CTL_RECENTER); - HDMI_WRITE(HDMI_FIFO_CTL, - drift | VC4_HDMI_FIFO_CTL_RECENTER); - - ret = wait_for(HDMI_READ(HDMI_FIFO_CTL) & - VC4_HDMI_FIFO_CTL_RECENTER_DONE, 1); - WARN_ONCE(ret, "Timeout waiting for " - "VC4_HDMI_FIFO_CTL_RECENTER_DONE"); } + + vc4_hdmi_recenter_fifo(vc4_hdmi); } static enum drm_mode_status -- 2.7.4