Re: [PATCH v4 70/78] drm/vc4: hdmi: Always recenter the HDMI FIFO

2020-07-28 Thread Dave Stevenson 
Hi Maxime

On Wed, 8 Jul 2020 at 18:44, Maxime Ripard  wrote:
>
> 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 

Reviewed-by: Dave Stevenson 

> ---
>  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 4058985940e6..00592c1ada73 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 = >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
> --
> git-series 0.9.1

[PATCH v4 70/78] drm/vc4: hdmi: Always recenter the HDMI FIFO

2020-07-08 Thread Maxime Ripard 
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 
---
 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 4058985940e6..00592c1ada73 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 = >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
-- 
git-series 0.9.1