openwrt/target/linux/brcm2708/patches-4.19/950-0628-drm-vc4-Max-resolution-of-7680-is-conditional-on-bei.patch

From 78bd1c0169850a388fd7a45af6dd566613403a8e Mon Sep 17 00:00:00 2001
From: Dave Stevenson <dave.stevenson@raspberrypi.org>
Date: Thu, 30 May 2019 15:55:15 +0100
Subject: [PATCH 628/703] drm/vc4: Max resolution of 7680 is conditional on
 being Pi4

The max resolution had been increased from 2048 to 7680 for all
platforms. This code is common with Pi0-3 which have a max render
target for GL of 2048, therefore the increased resolution has to
be conditional on the platform.
Switch based on whether the bcm2835-v3d node is found, as that is
not present on Pi4. (There is a potential configuration on Pi0-3
with no v3d, but this is very unlikely).

Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.org>
---
 drivers/gpu/drm/vc4/vc4_kms.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

--- a/drivers/gpu/drm/vc4/vc4_kms.c
+++ b/drivers/gpu/drm/vc4/vc4_kms.c
@@ -429,8 +429,14 @@ int vc4_kms_load(struct drm_device *dev)
 		return ret;
 	}
 
-	dev->mode_config.max_width = 7680;
-	dev->mode_config.max_height = 7680;
+	if (!drm_core_check_feature(dev, DRIVER_RENDER)) {
+		/* No V3D as part of vc4. Assume this is Pi4. */
+		dev->mode_config.max_width = 7680;
+		dev->mode_config.max_height = 7680;
+	} else {
+		dev->mode_config.max_width = 2048;
+		dev->mode_config.max_height = 2048;
+	}
 	dev->mode_config.funcs = &vc4_mode_funcs;
 	dev->mode_config.preferred_depth = 24;
 	dev->mode_config.async_page_flip = true;