2020-07-08 17:44:12

by Maxime Ripard

Subject: [PATCH v4 27/78] drm/vc4: crtc: Move HVS channel init before the PV initialisation

In order to avoid stale pixels getting stuck in an intermediate FIFO
between the HVS and the pixelvalve on BCM2711, we need to configure the HVS
channel before the pixelvalve is reset and configured.

Signed-off-by: Maxime Ripard <[email protected]>
---
drivers/gpu/drm/vc4/vc4_crtc.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/vc4/vc4_crtc.c b/drivers/gpu/drm/vc4/vc4_crtc.c
index 2c5ff45dc315..b7b0e19e2fe1 100644
--- a/drivers/gpu/drm/vc4/vc4_crtc.c
+++ b/drivers/gpu/drm/vc4/vc4_crtc.c
@@ -427,10 +427,6 @@ static void vc4_crtc_atomic_enable(struct drm_crtc *crtc,

require_hvs_enabled(dev);

- vc4_crtc_config_pv(crtc);
-
- CRTC_WRITE(PV_CONTROL, CRTC_READ(PV_CONTROL) | PV_CONTROL_EN);
-
/* Enable vblank irq handling before crtc is started otherwise
* drm_crtc_get_vblank() fails in vc4_crtc_update_dlist().
*/
@@ -438,6 +434,10 @@ static void vc4_crtc_atomic_enable(struct drm_crtc *crtc,

vc4_hvs_atomic_enable(crtc, old_state);

+ vc4_crtc_config_pv(crtc);
+
+ CRTC_WRITE(PV_CONTROL, CRTC_READ(PV_CONTROL) | PV_CONTROL_EN);
+
/* When feeding the transposer block the pixelvalve is unneeded and
* should not be enabled.
*/
--
git-series 0.9.1

2020-07-28 10:42:38

by Dave Stevenson

Subject: Re: [PATCH v4 27/78] drm/vc4: crtc: Move HVS channel init before the PV initialisation

Hi Maxime

On Wed, 8 Jul 2020 at 18:43, Maxime Ripard <[email protected]> wrote:
>
> In order to avoid stale pixels getting stuck in an intermediate FIFO
> between the HVS and the pixelvalve on BCM2711, we need to configure the HVS
> channel before the pixelvalve is reset and configured.
>
> Signed-off-by: Maxime Ripard <[email protected]>

Reviewed-by: Dave Stevenson <[email protected]>

> ---
> drivers/gpu/drm/vc4/vc4_crtc.c | 8 ++++----
> 1 file changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/gpu/drm/vc4/vc4_crtc.c b/drivers/gpu/drm/vc4/vc4_crtc.c
> index 2c5ff45dc315..b7b0e19e2fe1 100644
> --- a/drivers/gpu/drm/vc4/vc4_crtc.c
> +++ b/drivers/gpu/drm/vc4/vc4_crtc.c
> @@ -427,10 +427,6 @@ static void vc4_crtc_atomic_enable(struct drm_crtc *crtc,
>
> require_hvs_enabled(dev);
>
> - vc4_crtc_config_pv(crtc);
> -
> - CRTC_WRITE(PV_CONTROL, CRTC_READ(PV_CONTROL) | PV_CONTROL_EN);
> -
> /* Enable vblank irq handling before crtc is started otherwise
> * drm_crtc_get_vblank() fails in vc4_crtc_update_dlist().
> */
> @@ -438,6 +434,10 @@ static void vc4_crtc_atomic_enable(struct drm_crtc *crtc,
>
> vc4_hvs_atomic_enable(crtc, old_state);
>
> + vc4_crtc_config_pv(crtc);
> +
> + CRTC_WRITE(PV_CONTROL, CRTC_READ(PV_CONTROL) | PV_CONTROL_EN);
> +
> /* When feeding the transposer block the pixelvalve is unneeded and
> * should not be enabled.
> */
> --
> git-series 0.9.1