[PATCH v5 20/80] drm/vc4: crtc: Turn pixelvalve reset into a function

From: Maxime Ripard
Date: Thu Sep 03 2020 - 04:10:33 EST


The driver resets the pixelvalve FIFO in a number of occurences without
always using the same sequence.

Since this will be critical for BCM2711, let's move that sequence to a
function so that we are consistent.

Reviewed-by: Eric Anholt <eric@xxxxxxxxxx>
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_crtc.c | 20 +++++++++++++-------
1 file changed, 13 insertions(+), 7 deletions(-)

diff --git a/drivers/gpu/drm/vc4/vc4_crtc.c b/drivers/gpu/drm/vc4/vc4_crtc.c
index 41bc61d5a61f..c2ab907611e3 100644
--- a/drivers/gpu/drm/vc4/vc4_crtc.c
+++ b/drivers/gpu/drm/vc4/vc4_crtc.c
@@ -267,6 +267,15 @@ static struct drm_encoder *vc4_get_crtc_encoder(struct drm_crtc *crtc)
return NULL;
}

+static void vc4_crtc_pixelvalve_reset(struct drm_crtc *crtc)
+{
+ struct vc4_crtc *vc4_crtc = to_vc4_crtc(crtc);
+
+ /* The PV needs to be disabled before it can be flushed */
+ CRTC_WRITE(PV_CONTROL, CRTC_READ(PV_CONTROL) & ~PV_CONTROL_EN);
+ CRTC_WRITE(PV_CONTROL, CRTC_READ(PV_CONTROL) | PV_CONTROL_FIFO_CLR);
+}
+
static void vc4_crtc_config_pv(struct drm_crtc *crtc)
{
struct drm_encoder *encoder = vc4_get_crtc_encoder(crtc);
@@ -282,10 +291,7 @@ static void vc4_crtc_config_pv(struct drm_crtc *crtc)
u32 format = is_dsi ? PV_CONTROL_FORMAT_DSIV_24 : PV_CONTROL_FORMAT_24;
u8 ppc = pv_data->pixels_per_clock;

- /* Reset the PV fifo. */
- CRTC_WRITE(PV_CONTROL, 0);
- CRTC_WRITE(PV_CONTROL, PV_CONTROL_FIFO_CLR | PV_CONTROL_EN);
- CRTC_WRITE(PV_CONTROL, 0);
+ vc4_crtc_pixelvalve_reset(crtc);

CRTC_WRITE(PV_HORZA,
VC4_SET_FIELD((mode->htotal - mode->hsync_end) * pixel_rep / ppc,
@@ -430,9 +436,9 @@ static void vc4_crtc_atomic_enable(struct drm_crtc *crtc,

require_hvs_enabled(dev);

- /* Reset the PV fifo. */
- CRTC_WRITE(PV_CONTROL, CRTC_READ(PV_CONTROL) |
- PV_CONTROL_FIFO_CLR | PV_CONTROL_EN);
+ vc4_crtc_pixelvalve_reset(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().
--
git-series 0.9.1