[PATCH 03/15] drm/vc4: hvs: SCALER_DISPBKGND_AUTOHS is only valid on HVS4

From: Maxime Ripard
Date: Wed Dec 07 2022 - 06:55:53 EST


From: Dave Stevenson <dave.stevenson@xxxxxxxxxxxxxxx>

The bit used for SCALER_DISPBKGND_AUTOHS in SCALER_DISPBKGNDX
has been repurposed on HVS5 to configure whether a display can
win back-to-back arbitration wins for the COB.

This is not desirable, therefore only select this bit on HVS4,
and explicitly clear it on HVS5.

Fixes: c54619b0bfb3 ("drm/vc4: Add support for the BCM2711 HVS5")
Signed-off-by: Dave Stevenson <dave.stevenson@xxxxxxxxxxxxxxx>
Signed-off-by: Maxime Ripard <maxime@xxxxxxxxxx>
---
drivers/gpu/drm/vc4/vc4_hvs.c | 10 ++++++----
drivers/gpu/drm/vc4/vc4_regs.h | 1 +
2 files changed, 7 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/vc4/vc4_hvs.c b/drivers/gpu/drm/vc4/vc4_hvs.c
index b335815eac6a..57d99e7199ee 100644
--- a/drivers/gpu/drm/vc4/vc4_hvs.c
+++ b/drivers/gpu/drm/vc4/vc4_hvs.c
@@ -370,28 +370,30 @@ static int vc4_hvs_init_channel(struct vc4_hvs *hvs, struct drm_crtc *crtc,
* mode.
*/
dispctrl = SCALER_DISPCTRLX_ENABLE;
+ dispbkgndx = HVS_READ(SCALER_DISPBKGNDX(chan));

- if (!vc4->is_vc5)
+ if (!vc4->is_vc5) {
dispctrl |= VC4_SET_FIELD(mode->hdisplay,
SCALER_DISPCTRLX_WIDTH) |
VC4_SET_FIELD(mode->vdisplay,
SCALER_DISPCTRLX_HEIGHT) |
(oneshot ? SCALER_DISPCTRLX_ONESHOT : 0);
- else
+ dispbkgndx |= SCALER_DISPBKGND_AUTOHS;
+ } else {
dispctrl |= VC4_SET_FIELD(mode->hdisplay,
SCALER5_DISPCTRLX_WIDTH) |
VC4_SET_FIELD(mode->vdisplay,
SCALER5_DISPCTRLX_HEIGHT) |
(oneshot ? SCALER5_DISPCTRLX_ONESHOT : 0);
+ dispbkgndx &= ~SCALER5_DISPBKGND_BCK2BCK;
+ }

HVS_WRITE(SCALER_DISPCTRLX(chan), dispctrl);

- dispbkgndx = HVS_READ(SCALER_DISPBKGNDX(chan));
dispbkgndx &= ~SCALER_DISPBKGND_GAMMA;
dispbkgndx &= ~SCALER_DISPBKGND_INTERLACE;

HVS_WRITE(SCALER_DISPBKGNDX(chan), dispbkgndx |
- SCALER_DISPBKGND_AUTOHS |
((!vc4->is_vc5) ? SCALER_DISPBKGND_GAMMA : 0) |
(interlace ? SCALER_DISPBKGND_INTERLACE : 0));

diff --git a/drivers/gpu/drm/vc4/vc4_regs.h b/drivers/gpu/drm/vc4/vc4_regs.h
index f121905c404d..95deacdc31e7 100644
--- a/drivers/gpu/drm/vc4/vc4_regs.h
+++ b/drivers/gpu/drm/vc4/vc4_regs.h
@@ -366,6 +366,7 @@

#define SCALER_DISPBKGND0 0x00000044
# define SCALER_DISPBKGND_AUTOHS BIT(31)
+# define SCALER5_DISPBKGND_BCK2BCK BIT(31)
# define SCALER_DISPBKGND_INTERLACE BIT(30)
# define SCALER_DISPBKGND_GAMMA BIT(29)
# define SCALER_DISPBKGND_TESTMODE_MASK VC4_MASK(28, 25)

--
2.38.1