There is an issue in the DRM framebuffer driver changes.xeno74 wrote: ↑Thu Nov 02, 2023 1:03 pm 6.7-alpha1:
Virtual ppce500 QEMU machine with the virtio-gpu-pci or virtio-vga:
There is a fbdev issue. (The penguins are not displayed at boot time).
The kernel 6.6 final doesn't have this issue.Code: Select all
[ 0.889302] virtio-pci 0000:00:02.0: [drm] *ERROR* fbdev: Failed to setup generic emulation (ret=-2)
This is not a problem with the VirtIO GPU driver. The developers have changed the code for displaying the penguins for CPU cores at boot time.
Code: Select all
only allow logo use from fbcon
Geert Uytterhoeven has created a patch.
virtio_gpu_fbdev.patch
Code: Select all
--- a/drivers/gpu/drm/drm_client.c 2023-11-13 01:19:07.000000000 +0100
+++ b/drivers/gpu/drm/drm_client.c 2023-11-14 09:45:44.964199272 +0100
@@ -400,6 +400,16 @@ static int drm_client_buffer_addfb(struc
fb_req.width = width;
fb_req.height = height;
+ if (client->dev->mode_config.quirk_addfb_prefer_host_byte_order) {
+ if (format == DRM_FORMAT_XRGB8888)
+ format = DRM_FORMAT_HOST_XRGB8888;
+ if (format == DRM_FORMAT_ARGB8888)
+ format = DRM_FORMAT_HOST_ARGB8888;
+ if (format == DRM_FORMAT_RGB565)
+ format = DRM_FORMAT_HOST_RGB565;
+ if (format == DRM_FORMAT_XRGB1555)
+ format = DRM_FORMAT_HOST_XRGB1555;
+ }
fb_req.pixel_format = format;
fb_req.handles[0] = handle;
fb_req.pitches[0] = buffer->pitch;

I tested it with the virtio-vga and with the virtio-gpu-pci device in a virtual ppce500 QEMU/KVM HV machine with an e5500 CPU today.
Link to the thread: Fbdev issue after the drm updates 'drm-next-2023-10-31-1'