linux-kernel - [PATCH v3 057/105] drm/vc4: drv: Disable the CRTC at boot time

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Message-Id: <68bdae53a362e74f7e355fec1f18378c9e7fcaac.1590594512.git-series.maxime@cerno.tech>
Date:   Wed, 27 May 2020 17:48:27 +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 v3 057/105] drm/vc4: drv: Disable the CRTC at boot time

In order to prevent issues during the firmware to KMS transition, we need
to make sure the pixelvalve are disabled at boot time so that the DRM state
matches the hardware state.

Signed-off-by: Maxime Ripard <maxime@...no.tech>
---
 drivers/gpu/drm/vc4/vc4_crtc.c | 23 +++++++++++++++++++++++
 drivers/gpu/drm/vc4/vc4_drv.c  |  4 ++++
 drivers/gpu/drm/vc4/vc4_drv.h  |  1 +
 3 files changed, 28 insertions(+)

diff --git a/drivers/gpu/drm/vc4/vc4_crtc.c b/drivers/gpu/drm/vc4/vc4_crtc.c
index 3d2a31cad7fa..9efd7cb25590 100644
--- a/drivers/gpu/drm/vc4/vc4_crtc.c
+++ b/drivers/gpu/drm/vc4/vc4_crtc.c
@@ -409,6 +409,29 @@ static int vc4_crtc_disable(struct drm_crtc *crtc, unsigned int channel)
 	return 0;
 }
 
+int vc4_crtc_disable_at_boot(struct drm_crtc *crtc)
+{
+	struct drm_device *dev = crtc->dev;
+	struct vc4_crtc *vc4_crtc = to_vc4_crtc(crtc);
+	int channel;
+
+	if (of_device_is_compatible(vc4_crtc->pdev->dev.of_node,
+				    "brcm,bcm2835-txp"))
+		return 0;
+
+	if (!(CRTC_READ(PV_CONTROL) & PV_CONTROL_EN))
+		return 0;
+
+	if (!(CRTC_READ(PV_V_CONTROL) & PV_VCONTROL_VIDEN))
+		return 0;
+
+	channel = vc4_hvs_get_fifo_from_output(dev, vc4_crtc->data->hvs_output);
+	if (channel < 0)
+		return 0;
+
+	return vc4_crtc_disable(crtc, channel);
+}
+
 static void vc4_crtc_atomic_disable(struct drm_crtc *crtc,
 				    struct drm_crtc_state *old_state)
 {
diff --git a/drivers/gpu/drm/vc4/vc4_drv.c b/drivers/gpu/drm/vc4/vc4_drv.c
index ed7893ee188a..ea082b9d3c90 100644
--- a/drivers/gpu/drm/vc4/vc4_drv.c
+++ b/drivers/gpu/drm/vc4/vc4_drv.c
@@ -252,6 +252,7 @@ static int vc4_drm_bind(struct device *dev)
 	struct drm_device *drm;
 	struct vc4_dev *vc4;
 	struct device_node *node;
+	struct drm_crtc *crtc;
 	int ret = 0;
 
 	dev->coherent_dma_mask = DMA_BIT_MASK(32);
@@ -298,6 +299,9 @@ static int vc4_drm_bind(struct device *dev)
 	if (ret < 0)
 		goto unbind_all;
 
+	drm_for_each_crtc(crtc, drm)
+		vc4_crtc_disable_at_boot(crtc);
+
 	ret = drm_dev_register(drm, 0);
 	if (ret < 0)
 		goto unbind_all;
diff --git a/drivers/gpu/drm/vc4/vc4_drv.h b/drivers/gpu/drm/vc4/vc4_drv.h
index 99001f8783aa..32e9de15262a 100644
--- a/drivers/gpu/drm/vc4/vc4_drv.h
+++ b/drivers/gpu/drm/vc4/vc4_drv.h
@@ -797,6 +797,7 @@ void vc4_bo_remove_from_purgeable_pool(struct vc4_bo *bo);
 
 /* vc4_crtc.c */
 extern struct platform_driver vc4_crtc_driver;
+int vc4_crtc_disable_at_boot(struct drm_crtc *crtc);
 void vc4_crtc_handle_vblank(struct vc4_crtc *crtc);
 void vc4_crtc_txp_armed(struct drm_crtc_state *state);
 void vc4_crtc_get_margins(struct drm_crtc_state *state,
-- 
git-series 0.9.1