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 <20211028141938.3530-12-lukas.bulwahn@gmail.com> <CAK8P3a0Nq9hLbGiPCQTjVTiGFPR9-tdhN8Tf06Q=cWTgMK78yw@mail.gmail.com>
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From:   Joel Stanley <joel@jms.id.au>
Date:   Fri, 29 Oct 2021 06:36:08 +0000
Message-ID: <CACPK8XfiN5qziPHLU6J=bC34mcjz+ix7jjSX=xk9zsr7+vyTdw@mail.gmail.com>
Subject: Re: [PATCH 11/13] arm: npcm: drop selecting non-existing ARM_ERRATA_794072
To:     Arnd Bergmann <arnd@arndb.de>, Tomer Maimon <tmaimon77@gmail.com>,
        Avi Fishman <avifishman70@gmail.com>
Cc:     Lukas Bulwahn <lukas.bulwahn@gmail.com>,
        Russell King <linux@armlinux.org.uk>,
        Shawn Guo <shawnguo@kernel.org>,
        Sascha Hauer <s.hauer@pengutronix.de>,
        Pengutronix Kernel Team <kernel@pengutronix.de>,
        Fabio Estevam <festevam@gmail.com>,
        Sekhar Nori <nsekhar@ti.com>,
        Bartosz Golaszewski <brgl@bgdev.pl>,
        Linus Walleij <linusw@kernel.org>,
        Imre Kaloz <kaloz@openwrt.org>,
        Krzysztof Halasa <khalasa@piap.pl>,
        Tali Perry <tali.perry1@gmail.com>,
        Patrick Venture <venture@google.com>,
        Nancy Yuen <yuenn@google.com>,
        Benjamin Fair <benjaminfair@google.com>,
        Dinh Nguyen <dinguyen@kernel.org>,
        Linux ARM <linux-arm-kernel@lists.infradead.org>,
        OpenBMC Maillist <openbmc@lists.ozlabs.org>,
        kernel-janitors@vger.kernel.org,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
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Precedence: bulk

On Thu, 28 Oct 2021 at 14:57, Arnd Bergmann <arnd@arndb.de> wrote:
>
> On Thu, Oct 28, 2021 at 4:19 PM Lukas Bulwahn <lukas.bulwahn@gmail.com> wrote:
> >
> > There is no and never was a Kconfig for ARM_ERRATA_794072 in the kernel
> > tree. So, there is no need to select ARM_ERRATA_794072 in
> > ./arch/arm/mach-npcm/Kconfig.
> >
> > Simply drop selecting the non-existing ARM_ERRATA_794072.
> >
> > This issue was discovered with ./scripts/checkkconfigsymbols.py.
> >
> > Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
> > ---
>
> Could this be a typo? Maybe we need to enable a different errata workaround
> here, or maybe that code is actually needed and has to get sent.

Doing some searching, u-boot had a workaround for something called
ARM_ERRATA_794072.

https://github.com/u-boot/u-boot/commit/f71cbfe3ca5d2ad20159871700e8e248c8818ba8

Lore has the review history for that patch:

https://lore.kernel.org/all/6be32e0b5b454ed7b609317266a8e798@BLUPR03MB358.namprd03.prod.outlook.com/

It looks like it's the same workaround as ARM_ERRATA_742230, which the
kernel does implement.

It would be good to hear from the Nuvoton people, or an Arm person.

Cheers,

Joel