linux-kernel - [PATCH v4 5/9] drm/vc4: crtc: Only access the PixelValve registers if we have to

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Message-Id: <b55e31869304c748920c261eba87b3275dbeb297.1591882579.git-series.maxime@cerno.tech>
Date:   Thu, 11 Jun 2020 15:36:50 +0200
From:   Maxime Ripard <maxime@...no.tech>
To:     Nicolas Saenz Julienne <nsaenzjulienne@...e.de>,
        Eric Anholt <eric@...olt.net>
Cc:     dri-devel@...ts.freedesktop.org,
        linux-rpi-kernel@...ts.infradead.org,
        bcm-kernel-feedback-list@...adcom.com,
        linux-arm-kernel@...ts.infradead.org, linux-kernel@...r.kernel.org,
        Dave Stevenson <dave.stevenson@...pberrypi.com>,
        Tim Gover <tim.gover@...pberrypi.com>,
        Phil Elwell <phil@...pberrypi.com>,
        Maxime Ripard <maxime@...no.tech>
Subject: [PATCH v4 5/9] drm/vc4: crtc: Only access the PixelValve registers if we have to

The CRTC hooks are called both for the TXP and the pixelvalve, yet some
will read / write the registers as if the device was a pixelvalve, which
won't really work.

Let's make sure we only access those registers if we are running on a
PixelValve.

Reviewed-by: Eric Anholt <eric@...olt.net>
Signed-off-by: Maxime Ripard <maxime@...no.tech>
---
 drivers/gpu/drm/vc4/vc4_crtc.c | 19 +++++++++++++++----
 1 file changed, 15 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/vc4/vc4_crtc.c b/drivers/gpu/drm/vc4/vc4_crtc.c
index 6f1a1062db8f..49c9954d3e00 100644
--- a/drivers/gpu/drm/vc4/vc4_crtc.c
+++ b/drivers/gpu/drm/vc4/vc4_crtc.c
@@ -357,6 +357,7 @@ static void require_hvs_enabled(struct drm_device *dev)
 static void vc4_crtc_atomic_disable(struct drm_crtc *crtc,
 				    struct drm_crtc_state *old_state)
 {
+	struct vc4_crtc_state *vc4_state = to_vc4_crtc_state(crtc->state);
 	struct drm_device *dev = crtc->dev;
 	struct vc4_crtc *vc4_crtc = to_vc4_crtc(crtc);
 	int ret;
@@ -366,10 +367,12 @@ static void vc4_crtc_atomic_disable(struct drm_crtc *crtc,
 	/* Disable vblank irq handling before crtc is disabled. */
 	drm_crtc_vblank_off(crtc);
 
-	CRTC_WRITE(PV_V_CONTROL,
-		   CRTC_READ(PV_V_CONTROL) & ~PV_VCONTROL_VIDEN);
-	ret = wait_for(!(CRTC_READ(PV_V_CONTROL) & PV_VCONTROL_VIDEN), 1);
-	WARN_ONCE(ret, "Timeout waiting for !PV_VCONTROL_VIDEN\n");
+	if (!vc4_state->feed_txp) {
+		CRTC_WRITE(PV_V_CONTROL,
+			   CRTC_READ(PV_V_CONTROL) & ~PV_VCONTROL_VIDEN);
+		ret = wait_for(!(CRTC_READ(PV_V_CONTROL) & PV_VCONTROL_VIDEN), 1);
+		WARN_ONCE(ret, "Timeout waiting for !PV_VCONTROL_VIDEN\n");
+	}
 
 	vc4_hvs_atomic_disable(crtc, old_state);
 
@@ -503,6 +506,10 @@ static int vc4_crtc_atomic_check(struct drm_crtc *crtc,
 static int vc4_enable_vblank(struct drm_crtc *crtc)
 {
 	struct vc4_crtc *vc4_crtc = to_vc4_crtc(crtc);
+	struct vc4_crtc_state *vc4_state = to_vc4_crtc_state(crtc->state);
+
+	if (vc4_state->feed_txp)
+		return 0;
 
 	CRTC_WRITE(PV_INTEN, PV_INT_VFP_START);
 
@@ -512,6 +519,10 @@ static int vc4_enable_vblank(struct drm_crtc *crtc)
 static void vc4_disable_vblank(struct drm_crtc *crtc)
 {
 	struct vc4_crtc *vc4_crtc = to_vc4_crtc(crtc);
+	struct vc4_crtc_state *vc4_state = to_vc4_crtc_state(crtc->state);
+
+	if (vc4_state->feed_txp)
+		return;
 
 	CRTC_WRITE(PV_INTEN, 0);
 }
-- 
git-series 0.9.1