drm/vc4: drv: Register a different driver on BCM2711

Prior to the BCM2711/RaspberryPi4, the GPU was a part of the display
components of the SoC. It was thus a part of the vc4 driver.

However, with the BCM2711, it got split out and thus the v3d driver was
created. The vc4 driver now only handles the display part.

We didn't properly split out the code when doing the BCM2711 support
though, and most of the code around buffer allocations is still
involved, even though it doesn't have the backing hardware anymore.

Let's start the split out by creating a new drm_driver that only reports
and uses what we support on the BCM2711. The ioctl were properly
filtered already, but we were still exposing a .gem_create_object hook,
as well as having an .open and .postclose hooks which are only relevant
on older generations.
Reviewed-by: Melissa Wen <mwen@igalia.com>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220610115149.964394-6-maxime@cerno.tech

drivers/gpu/drm/vc4/vc4_drv.c

@@ -76,6 +76,19 @@ int vc4_dumb_fixup_args(struct drm_mode_create_dumb *args)
 	return 0;
 }
 
+static int vc5_dumb_create(struct drm_file *file_priv,
+			   struct drm_device *dev,
+			   struct drm_mode_create_dumb *args)
+{
+	int ret;
+
+	ret = vc4_dumb_fixup_args(args);
+	if (ret)
+		return ret;
+
+	return drm_gem_cma_dumb_create_internal(file_priv, dev, args);
+}
+
 static int vc4_get_param_ioctl(struct drm_device *dev, void *data,
 			       struct drm_file *file_priv)
 {
@@ -173,7 +186,7 @@ static const struct drm_ioctl_desc vc4_drm_ioctls[] = {
 	DRM_IOCTL_DEF_DRV(VC4_PERFMON_GET_VALUES, vc4_perfmon_get_values_ioctl, DRM_RENDER_ALLOW),
 };
 
-static struct drm_driver vc4_drm_driver = {
+static const struct drm_driver vc4_drm_driver = {
 	.driver_features = (DRIVER_MODESET |
 			    DRIVER_ATOMIC |
 			    DRIVER_GEM |
@@ -202,6 +215,27 @@ static struct drm_driver vc4_drm_driver = {
 	.patchlevel = DRIVER_PATCHLEVEL,
 };
 
+static const struct drm_driver vc5_drm_driver = {
+	.driver_features = (DRIVER_MODESET |
+			    DRIVER_ATOMIC |
+			    DRIVER_GEM),
+
+#if defined(CONFIG_DEBUG_FS)
+	.debugfs_init = vc4_debugfs_init,
+#endif
+
+	DRM_GEM_CMA_DRIVER_OPS_WITH_DUMB_CREATE(vc5_dumb_create),
+
+	.fops = &vc4_drm_fops,
+
+	.name = DRIVER_NAME,
+	.desc = DRIVER_DESC,
+	.date = DRIVER_DATE,
+	.major = DRIVER_MAJOR,
+	.minor = DRIVER_MINOR,
+	.patchlevel = DRIVER_PATCHLEVEL,
+};
+
 static void vc4_match_add_drivers(struct device *dev,
 				  struct component_match **match,
 				  struct platform_driver *const *drivers,
@@ -225,6 +259,7 @@ static void vc4_match_add_drivers(struct device *dev,
 static int vc4_drm_bind(struct device *dev)
 {
 	struct platform_device *pdev = to_platform_device(dev);
+	const struct drm_driver *driver;
 	struct rpi_firmware *firmware = NULL;
 	struct drm_device *drm;
 	struct vc4_dev *vc4;
@@ -236,14 +271,12 @@ static int vc4_drm_bind(struct device *dev)
 	dev->coherent_dma_mask = DMA_BIT_MASK(32);
 
 	is_vc5 = of_device_is_compatible(dev->of_node, "brcm,bcm2711-vc5");
+	if (is_vc5)
+		driver = &vc5_drm_driver;
+	else
+		driver = &vc4_drm_driver;
 
-	/* If VC4 V3D is missing, don't advertise render nodes. */
-	node = of_find_matching_node_and_match(NULL, vc4_v3d_dt_match, NULL);
-	if (!node || !of_device_is_available(node))
-		vc4_drm_driver.driver_features &= ~DRIVER_RENDER;
-	of_node_put(node);
-
-	vc4 = devm_drm_dev_alloc(dev, &vc4_drm_driver, struct vc4_dev, base);
+	vc4 = devm_drm_dev_alloc(dev, driver, struct vc4_dev, base);
 	if (IS_ERR(vc4))
 		return PTR_ERR(vc4);
 	vc4->is_vc5 = is_vc5;
@@ -275,7 +308,7 @@ static int vc4_drm_bind(struct device *dev)
 			return -EPROBE_DEFER;
 	}
 
-	ret = drm_aperture_remove_framebuffers(false, &vc4_drm_driver);
+	ret = drm_aperture_remove_framebuffers(false, driver);
 	if (ret)
 		return ret;