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

[Marek Szyprowski]

On 02.06.2021 16:14, Arnd Bergmann wrote:
> 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.

Indeed, after disabling DRM_VC4 in the .config, system boots fine and 
seems to be working correctly.

Best regards
-- 
Marek Szyprowski, PhD
Samsung R&D Institute Poland