From mboxrd@z Thu Jan  1 00:00:00 1970
From: Peter De Schrijver <pdeschrijver@nvidia.com>
Subject: Re: [PATCH V6 01/21] irqchip: tegra: Do not disable COP IRQ during
 suspend
Date: Thu, 25 Jul 2019 13:38:14 +0300
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To: Dmitry Osipenko <digetx@gmail.com>
Cc: Sowjanya Komatineni <skomatineni@nvidia.com>, thierry.reding@gmail.com, jonathanh@nvidia.com, tglx@linutronix.de, jason@lakedaemon.net, marc.zyngier@arm.com, linus.walleij@linaro.org, stefan@agner.ch, mark.rutland@arm.com, pgaikwad@nvidia.com, sboyd@kernel.org, linux-clk@vger.kernel.org, linux-gpio@vger.kernel.org, jckuo@nvidia.com, josephl@nvidia.com, talho@nvidia.com, linux-tegra@vger.kernel.org, linux-kernel@vger.kernel.org, mperttunen@nvidia.com, spatra@nvidia.com, robh+dt@kernel.org, devicetree@vger.kernel.org
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On Thu, Jul 25, 2019 at 01:33:48PM +0300, Peter De Schrijver wrote:
> On Thu, Jul 25, 2019 at 01:05:13PM +0300, Dmitry Osipenko wrote:
> > 25.07.2019 12:55, Peter De Schrijver =D0=BF=D0=B8=D1=88=D0=B5=D1=82:
> > > On Mon, Jul 22, 2019 at 12:54:51PM +0300, Dmitry Osipenko wrote:
> > >>
> > >> All Tegra SoCs support SC7, hence the 'supports_sc7' and the comment
> > >> doesn't sound correct to me. Something like 'firmware_sc7' should su=
it
> > >> better here.
> > >>
> > >>> +			writel_relaxed(~0ul, ictlr + ICTLR_COP_IER_CLR);
> > >>
> > >> Secondly, I'm also not sure why COP interrupts need to be disabled f=
or
> > >> pre-T210 at all, since COP is unused. This looks to me like it was
> > >> cut-n-pasted from downstream kernel without a good reason and could =
be
> > >> simply removed.
> > >=20
> > > I don't think we can rely on the fact that COP is unused. People can
> > > write their own code to run on COP.
> >=20
> > 1. Not upstream - doesn't matter.
> >=20
>=20
> The code is not part of the kernel, so obviously it's not upstream?
>=20
> > 2. That's not very good if something unknown is running on COP and then
> > kernel suddenly intervenes, don't you think so?
>=20
> Unless the code was written with this in mind.
>=20

Looking at this again, I don't think we need to enable the IRQ at all.

Peter.