[openwrt/openwrt] armsr: enable framebuffer emulation for virtio-gpu/drm displays

[LEDE Commits]

hauke pushed a commit to openwrt/openwrt.git, branch main:
https://git.openwrt.org/ea7383e7215c36e47a769f34c57aa458300b8bc2

commit ea7383e7215c36e47a769f34c57aa458300b8bc2
Author: Mathew McBride <matt at traverse.com.au>
AuthorDate: Sun May 26 14:12:58 2024 +1000

    armsr: enable framebuffer emulation for virtio-gpu/drm displays
    
    This was discovered when trying to run OpenWrt on Hetzner Cloud's
    Arm-based instances.
    
    Hetzner uses QEMU/KVM with virtio-gpu as the main display device,
    together with an ACPI firmware. This was not displaying a console
    previously.
    
    This setup can be emulated by qemu using options below:
    qemu-system-aarch64 \
        -machine virt \
        -bios QEMU_EFI.fd \
        -device virtio-gpu \
        -usb \
        -device qemu-xhci,id=xhci \
        -device usb-tablet,bus=xhci.0 \
        -device usb-kbd,bus=xhci.0 \
        -vnc :0
    
    Signed-off-by: Mathew McBride <matt at traverse.com.au>
---
 target/linux/armsr/config-6.6 | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/target/linux/armsr/config-6.6 b/target/linux/armsr/config-6.6
index 8b4f291c9f..304602ebbd 100644
--- a/target/linux/armsr/config-6.6
+++ b/target/linux/armsr/config-6.6
@@ -105,6 +105,9 @@ CONFIG_DMA_REMAP=y
 CONFIG_DMI=y
 CONFIG_DMIID=y
 CONFIG_DMI_SYSFS=y
+CONFIG_DRM_FBDEV_EMULATION=y
+CONFIG_DRM_FBDEV_OVERALLOC=100
+CONFIG_DRM_LOAD_EDID_FIRMWARE=y
 CONFIG_DTC=y
 CONFIG_EDAC_SUPPORT=y
 CONFIG_EFI=y