Hello.
As of Linux 5.18.0, module vc4 apparently isn't working on Raspberry Pi
3B any more.
If a monitor is attached to the device, the boot messages show up as
usual, but right when KMS starts, the screen turns black. Similarly, the
screen also turns black when the module is blacklisted at boot time and
loaded from the running system.
The problem looks quite similar to the one posted some months ago in [1].
Unfortunately, looking through systemd's journal didn't seem to yield
any real hint. Nevertheless, the results from grepping vc4 are
→ 5.17.1
> kernel: vc4-drm soc:gpu: bound 3f400000.hvs (ops vc4_hvs_ops [vc4])
> kernel: rc rc0: vc4 as /devices/platform/soc/3f902000.hdmi/rc/rc0
> kernel: input: vc4 as /devices/platform/soc/3f902000.hdmi/rc/rc0/input0
> kernel: vc4-drm soc:gpu: bound 3f902000.hdmi (ops vc4_hdmi_ops [vc4])
> kernel: vc4-drm soc:gpu: bound 3f806000.vec (ops vc4_vec_ops [vc4])
> kernel: vc4-drm soc:gpu: bound 3f004000.txp (ops vc4_txp_ops [vc4])
> kernel: vc4-drm soc:gpu: bound 3f206000.pixelvalve (ops vc4_crtc_ops
[vc4])
> kernel: vc4-drm soc:gpu: bound 3f207000.pixelvalve (ops vc4_crtc_ops
[vc4])
> kernel: vc4-drm soc:gpu: bound 3f807000.pixelvalve (ops vc4_crtc_ops
[vc4])
> kernel: vc4-drm soc:gpu: bound 3fc00000.v3d (ops vc4_v3d_ops [vc4])
> kernel: fb0: switching to vc4 from simple
> kernel: [drm] Initialized vc4 0.0.0 20140616 for soc:gpu on minor 0
> kernel: vc4-drm soc:gpu: [drm] fb0: vc4drmfb frame buffer device
> systemd-logind[338]: Watching system buttons on /dev/input/event0 (vc4)
→ 5.18.0
> kernel: fb0: switching to vc4 from simple
> kernel: vc4-drm soc:gpu: bound 3f400000.hvs (ops vc4_hvs_ops [vc4])
> kernel: rc rc0: vc4 as /devices/platform/soc/3f902000.hdmi/rc/rc0
> kernel: input: vc4 as /devices/platform/soc/3f902000.hdmi/rc/rc0/input0
> kernel: vc4-drm soc:gpu: bound 3f902000.hdmi (ops vc4_hdmi_ops [vc4])
> kernel: vc4-drm soc:gpu: bound 3f806000.vec (ops vc4_vec_ops [vc4])
> kernel: vc4-drm soc:gpu: bound 3f004000.txp (ops vc4_txp_ops [vc4])
> kernel: vc4-drm soc:gpu: bound 3f206000.pixelvalve (ops vc4_crtc_ops
[vc4])
> kernel: vc4-drm soc:gpu: bound 3f207000.pixelvalve (ops vc4_crtc_ops
[vc4])
> kernel: vc4-drm soc:gpu: bound 3f807000.pixelvalve (ops vc4_crtc_ops
[vc4])
> kernel: vc4-drm soc:gpu: bound 3fc00000.v3d (ops vc4_v3d_ops [vc4])
> kernel: [drm] Initialized vc4 0.0.0 20140616 for soc:gpu on minor 0
> kernel: vc4-drm soc:gpu: [drm] fb0: vc4drmfb frame buffer device
> systemd-logind[337]: Watching system buttons on /dev/input/event0 (vc4)
Regards,
Peter Mattern
[1]
https://lists.freedesktop.org/archives/dri-devel/2022-January/339458.html
