Re: [PATCH] soc: renesas: rmobile-sysc: Set OF_POPULATED and absorb reset handling

From: Sebastian Reichel <sre@kernel.org>
To: Geert Uytterhoeven <geert@linux-m68k.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>
Subject: Re: [PATCH] soc: renesas: rmobile-sysc: Set OF_POPULATED and absorb reset handling
Date: Tue, 2 Mar 2021 18:25:40 +0100	[thread overview]
Message-ID: <20210302172540.suq6m7cbulorp4at@earth.universe> (raw)
In-Reply-To: <CAMuHMdULLDcRFhOQrGXuRxTcMeX5bc3fi-CkSSmrejSP6JUKWA@mail.gmail.com>

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Hi Geert,

On Tue, Mar 02, 2021 at 05:18:21PM +0100, Geert Uytterhoeven wrote:
> 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/

Ah I remember seeing that, wondering why I am being CC'd and
ignoring it :)

Thanks for the pointer,

-- Sebastian

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