[PATCH v3 018/105] drm/vc4: plane: Move additional planes creation to driver

Maxime Ripard maxime at cerno.tech
Wed May 27 15:47:48 UTC 2020

So far the plane creation was done when each CRTC was bound, and those
planes were only tied to the CRTC that was registering them.

This causes two main issues:
  - The planes in the vc4 hardware are actually not tied to any CRTC, but
    can be used with every combination

  - More importantly, so far, we allocate 10 planes per CRTC, with 3 CRTCs.
    However, the next generation of hardware will have 5 CRTCs, putting us
    well above the maximum of 32 planes currently allowed by DRM.

This patch is the first one in a series of patches that will take down both
of these issues so that we can support the next generation of hardware
while keeping a good amount of planes.

We start by changing the way the planes are registered to first registering
the primary planes for each CRTC in the CRTC bind function as we used to,
but moving the overlay and cursor creation to the main driver bind
function, after all the CRTCs have been bound.

This will slightly change the ID order of the planes, since the primary
planes of all CRTCs will be first, and then a pattern of 8 overlays, 1
cursor plane for each CRTC.

This shouldn't cause any trouble since the ordering between the planes is
preserved though.

Signed-off-by: Maxime Ripard <maxime at cerno.tech>
 drivers/gpu/drm/vc4/vc4_crtc.c | 4 ----
 drivers/gpu/drm/vc4/vc4_drv.c  | 7 +++++++
 2 files changed, 7 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/vc4/vc4_crtc.c b/drivers/gpu/drm/vc4/vc4_crtc.c
index 29c72c322c6b..2131164779dd 100644
--- a/drivers/gpu/drm/vc4/vc4_crtc.c
+++ b/drivers/gpu/drm/vc4/vc4_crtc.c
@@ -1192,10 +1192,6 @@ static int vc4_crtc_bind(struct device *dev, struct device *master, void *data)
 	drm_crtc_enable_color_mgmt(crtc, 0, true, crtc->gamma_size);
-	ret = vc4_plane_create_additional_planes(drm, crtc);
-	if (ret)
-		goto err_destroy_planes;
diff --git a/drivers/gpu/drm/vc4/vc4_drv.c b/drivers/gpu/drm/vc4/vc4_drv.c
index d7f554a6f0ed..daf07a61a7b5 100644
--- a/drivers/gpu/drm/vc4/vc4_drv.c
+++ b/drivers/gpu/drm/vc4/vc4_drv.c
@@ -250,6 +250,7 @@ static int vc4_drm_bind(struct device *dev)
 	struct platform_device *pdev = to_platform_device(dev);
 	struct drm_device *drm;
+	struct drm_crtc *crtc;
 	struct vc4_dev *vc4;
 	struct device_node *node;
 	int ret = 0;
@@ -288,6 +289,12 @@ static int vc4_drm_bind(struct device *dev)
 	if (ret)
 		goto gem_destroy;
+	drm_for_each_crtc(crtc, drm) {
+		ret = vc4_plane_create_additional_planes(drm, crtc);
+		if (ret)
+			continue;
+	}
 	drm_fb_helper_remove_conflicting_framebuffers(NULL, "vc4drmfb", false);
 	ret = vc4_kms_load(drm);
git-series 0.9.1

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