REGRESSION in 6.0-rc7 caused by patch "ARM/dma-mapping: use dma-direct unconditionally"

[Pali Rohár]

On Tuesday 04 October 2022 14:59:29 Marcin Wojtas wrote:
> wt., 4 paź 2022 o 14:37 Marek Behún <kabel at kernel.org> napisał(a):
> > And now I am wondering about whether this didn't also cause the buffer
> > manager not working on Armada 3720. Marvell just gave an erratum that
> > HWBM is broken on 3720, but maybe they didn't notice this and just gave
> > up.
> 
> I implemented inital version of this support, which was never
> published > 5y ago (I checked my oldest repos, but the code is gone
> unfortunately). I don't recall exact HW issue justification - I
> remember it was not related to coherency though, but the decision was
> to drop it.
> 
> >
> > Also mvneta works only with one CPU on 3720 (see usage of
> > pp->neta_armada3700 in mvneta.c), which I also still don't know why,
> > and maybe it is related to this.
> >
> 
> The single-core processing is result of the problems with per-CPU IRQ
> routing for the NETA controllers (never to be fixed eventually), not
> related to coherency whatsoever.
> 
> Best regards,
> Marcin

FYI this is described in A3720 errata document.