[PATCH] arm64: cache: Lower ARCH_DMA_MINALIGN to 64 (L1_CACHE_BYTES)

[Arnd Bergmann]

On Wed, Jun 2, 2021 at 4:09 PM Marek Szyprowski
<m.szyprowski at samsung.com> wrote:
> On 02.06.2021 15:51, Mark Rutland wrote:
> [   13.938691] debugfs: Directory '3f902000.hdmi' with parent 'vc4-hdmi'
> already present!
> [   13.983716] vc4-drm soc:gpu: bound 3f902000.hdmi (ops vc4_hdmi_ops)
> [   13.991816] vc4-drm soc:gpu: bound 3f806000.vec (ops vc4_vec_ops)
> [   14.000945] vc4-drm soc:gpu: bound 3f400000.hvs (ops vc4_hvs_ops)
> [   14.009644] vc4-drm soc:gpu: bound 3f004000.txp (ops vc4_txp_ops)
> [   14.017547] vc4-drm soc:gpu: bound 3f206000.pixelvalve (ops vc4_crtc_ops)
> [   14.025780] vc4-drm soc:gpu: bound 3f207000.pixelvalve (ops vc4_crtc_ops)
> [   14.033995] vc4-drm soc:gpu: bound 3f807000.pixelvalve (ops vc4_crtc_ops)
> [   14.042196] vc4-drm soc:gpu: bound 3fc00000.v3d (ops vc4_v3d_ops)
> [....] Waiting for /dev to be fully populated...[   14.112812] [drm]
> Initialized vc4 0.0.0 20140616 for soc:gpu on minor 0
> done.

I wonder if the vc4's cache is involved here rather than the CPU cache.
If it's that, then removing the vc4 drivers should make it boot reliably, and
it might be possible to fix it by manually padding any allocations that get
passed to the GPU.

       Arnd