Re: [PATCH v2 0/7] soc: renesas: rcar-gen3-sysc: Fix power request conflicts

From: Geert Uytterhoeven <geert@linux-m68k.org>
To: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>,
	Magnus Damm <magnus.damm@gmail.com>,
	Simon Horman <horms@verge.net.au>,
	"linux-renesas-soc@vger.kernel.org" 
	<linux-renesas-soc@vger.kernel.org>,
	"linux-arm-kernel@lists.infradead.org" 
	<linux-arm-kernel@lists.infradead.org>
Subject: Re: [PATCH v2 0/7] soc: renesas: rcar-gen3-sysc: Fix power request conflicts
Date: Tue, 3 Sep 2019 14:10:42 +0200	[thread overview]
Message-ID: <CAMuHMdW6WhNYHL-3vWj82uRUuxxuYfk3BRnqu8SWnh3i6zkXjw@mail.gmail.com> (raw)
In-Reply-To: <TYAPR01MB45445637B824C0464A1CD5ADD8A20@TYAPR01MB4544.jpnprd01.prod.outlook.com>

On Thu, Aug 29, 2019 at 6:14 AM Yoshihiro Shimoda
<yoshihiro.shimoda.uh@renesas.com> wrote:
> > From: Geert Uytterhoeven, Sent: Wednesday, August 28, 2019 8:36 PM
> > Recent R-Car Gen3 SoCs added an External Request Mask Register to the
> > System Controller (SYSC).  This register allows to mask external power
> > requests for CPU or 3DG domains, to prevent conflicts between powering
> > off CPU cores or the 3D Graphics Engine, and changing the state of
> > another power domain through SYSC, which could lead to CPG state machine
> > lock-ups.
> >
> > This patch series starts making use of this register.  Note that the
> > register is optional, and that its location and contents are
> > SoC-specific.
> >
> > This was inspired by a patch in the BSP by Dien Pham
> > <dien.pham.ry@renesas.com>.
> >
> > Note that the issue fixed cannot happen in the upstream kernel, as
> > upstream has no support for graphics acceleration yet.  SoCs lacking the
> > External Request Mask Register may need a different mitigation in the
> > future.
> >
> > Changes compared to v1[1]:
> >   - Improve description of cover letter and first patch.
> >
> > Changes compared to RFC[2]:
> >   - Rebased.
> >
> > This has been boot-tested on R-Car H3 ES1.0, H3 ES2.0, M3-W ES1.0, M3-N,
> > V3M, and E3 (only the last 3 have this register!), and regression-tested
> > on R-Car Gen2.
> >
> > This has not been tested on R-Car H3 ES3.0, M3-W ES2.0, and V3H.
>
> I also boot-tested on R-Car H3 ES3.0 and M3-W ES3.0.
> And I reviewed all patches, so:
>
> Reviewed-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>

Thanks, queued in renesas-devel for v5.5.

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds