In order to avoid pixels getting stuck in an unflushable FIFO, we need when we disable the HDMI controller to switch away from getting our pixels from the pixelvalve and instead use blank pixels, and switch back to the pixelvalve when we enable the HDMI controller. Reviewed-by: Dave Stevenson <dave.stevenson@xxxxxxxxxxxxxxx> Tested-by: Chanwoo Choi <cw00.choi@xxxxxxxxxxx> Tested-by: Hoegeun Kwon <hoegeun.kwon@xxxxxxxxxxx> Tested-by: Stefan Wahren <stefan.wahren@xxxxxxxx> Signed-off-by: Maxime Ripard <maxime@xxxxxxxxxx> --- drivers/gpu/drm/vc4/vc4_hdmi.c | 9 +++++++++ drivers/gpu/drm/vc4/vc4_regs.h | 3 +++ 2 files changed, 12 insertions(+) diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.c b/drivers/gpu/drm/vc4/vc4_hdmi.c index 8bf69cafdd7e..ab7abb409de2 100644 --- a/drivers/gpu/drm/vc4/vc4_hdmi.c +++ b/drivers/gpu/drm/vc4/vc4_hdmi.c @@ -325,6 +325,12 @@ static void vc4_hdmi_encoder_post_crtc_disable(struct drm_encoder *encoder) struct vc4_hdmi *vc4_hdmi = encoder_to_vc4_hdmi(encoder); HDMI_WRITE(HDMI_RAM_PACKET_CONFIG, 0); + + HDMI_WRITE(HDMI_VID_CTL, HDMI_READ(HDMI_VID_CTL) | + VC4_HD_VID_CTL_CLRRGB | VC4_HD_VID_CTL_CLRSYNC); + + HDMI_WRITE(HDMI_VID_CTL, + HDMI_READ(HDMI_VID_CTL) | VC4_HD_VID_CTL_BLANKPIX); } static void vc4_hdmi_encoder_post_crtc_powerdown(struct drm_encoder *encoder) @@ -563,6 +569,9 @@ static void vc4_hdmi_encoder_post_crtc_enable(struct drm_encoder *encoder) (vsync_pos ? 0 : VC4_HD_VID_CTL_VSYNC_LOW) | (hsync_pos ? 0 : VC4_HD_VID_CTL_HSYNC_LOW)); + HDMI_WRITE(HDMI_VID_CTL, + HDMI_READ(HDMI_VID_CTL) & ~VC4_HD_VID_CTL_BLANKPIX); + if (vc4_encoder->hdmi_monitor) { HDMI_WRITE(HDMI_SCHEDULER_CONTROL, HDMI_READ(HDMI_SCHEDULER_CONTROL) | diff --git a/drivers/gpu/drm/vc4/vc4_regs.h b/drivers/gpu/drm/vc4/vc4_regs.h index d1e8961edaa0..30af52b406f1 100644 --- a/drivers/gpu/drm/vc4/vc4_regs.h +++ b/drivers/gpu/drm/vc4/vc4_regs.h @@ -723,6 +723,9 @@ # define VC4_HD_VID_CTL_FRAME_COUNTER_RESET BIT(29) # define VC4_HD_VID_CTL_VSYNC_LOW BIT(28) # define VC4_HD_VID_CTL_HSYNC_LOW BIT(27) +# define VC4_HD_VID_CTL_CLRSYNC BIT(24) +# define VC4_HD_VID_CTL_CLRRGB BIT(23) +# define VC4_HD_VID_CTL_BLANKPIX BIT(18) # define VC4_HD_CSC_CTL_ORDER_MASK VC4_MASK(7, 5) # define VC4_HD_CSC_CTL_ORDER_SHIFT 5 -- git-series 0.9.1 _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel