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References: <20210205133319.1921108-1-geert+renesas@glider.be> <20210302154406.n4d6euiruwan4pm5@earth.universe>
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From:   Geert Uytterhoeven <geert@linux-m68k.org>
Date:   Tue, 2 Mar 2021 17:18:21 +0100
Message-ID: <CAMuHMdULLDcRFhOQrGXuRxTcMeX5bc3fi-CkSSmrejSP6JUKWA@mail.gmail.com>
Subject: Re: [PATCH] soc: renesas: rmobile-sysc: Set OF_POPULATED and absorb
 reset handling
To:     Sebastian Reichel <sre@kernel.org>
Cc:     Magnus Damm <magnus.damm@gmail.com>,
        Saravana Kannan <saravanak@google.com>,
        Linux-Renesas <linux-renesas-soc@vger.kernel.org>,
        Linux ARM <linux-arm-kernel@lists.infradead.org>,
        Linux PM list <linux-pm@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
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Hi Sebastian,

On Tue, Mar 2, 2021 at 4:44 PM Sebastian Reichel <sre@kernel.org> wrote:
> On Fri, Feb 05, 2021 at 02:33:19PM +0100, Geert Uytterhoeven wrote:
> > Currently, there are two drivers binding to the R-Mobile System
> > Controller (SYSC):
> >   - The rmobile-sysc driver registers PM domains from a core_initcall(),
> >     and does not use a platform driver,
> >   - The rmobile-reset driver registers a reset handler, and does use a
> >     platform driver.
> >
> > As fw_devlink only considers devices, it does not know that the
> > rmobile-sysc driver is ready.  Hence if fw_devlink is enabled, probing
> > of on-chip devices that are part of the SYSC PM domain is deferred until
> > the optional rmobile-reset has been bound, which may happen too late
> > (for e.g. the system timer on SoCs lacking an ARM architectured or
> > global timer), or not at all, leading to complete system boot failures.
> >
> > Fix this by:
> >   1. Setting the OF_POPULATED flag for the SYSC device node after
> >      successful initialization.
> >      This will make of_link_to_phandle() ignore the SYSC device node as
> >      a dependency, making consumer devices probe again.
> >   2. Move reset handling from its own driver into the rmobile-sysc
> >      driver.
> >      This is needed because setting OF_POPULATED prevents the
> >      rmobile-reset driver from binding against the same device.
> >
> > Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
> > ---
> > To be queued in renesas-devel for v5.13.
>
> Acked-by: Sebastian Reichel <sre@kernel.org>

In the meantime, this has method been abandoned, and this patch was
superseded by "[PATCH v2] soc: renesas: rmobile-sysc: Mark fwnode when
PM domain is added"
https://lore.kernel.org/linux-arm-kernel/20210216123958.3180014-1-geert+renesas@glider.be/

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