linux-kernel - Re: [PATCH 4/4] arm64: dts: qcom: sc7180: disable quad mode for spi nor

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <CAD=FV=UvDZOgJ0TxeBYGgDMqSUYUX9am+QAMEXpRQ0C-Hh=kVw@mail.gmail.com>
Date:   Tue, 15 Aug 2023 12:32:15 -0700
From:   Doug Anderson <dianders@...omium.org>
To:     Hsin-Yi Wang <hsinyi@...omium.org>
Cc:     Tudor Ambarus <tudor.ambarus@...aro.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@...aro.org>,
        Conor Dooley <conor+dt@...nel.org>,
        Matthias Brugger <matthias.bgg@...il.com>,
        Bjorn Andersson <andersson@...nel.org>,
        Pratyush Yadav <pratyush@...nel.org>,
        Michael Walle <michael@...le.cc>,
        "Miquel Raynal )" <miquel.raynal@...tlin.com>,
        "Richard Weinberger )" <richard@....at>,
        "Vignesh Raghavendra )" <vigneshr@...com>,
        Rob Herring <robh+dt@...nel.org>,
        linux-mtd@...ts.infradead.org, devicetree@...r.kernel.org,
        linux-kernel@...r.kernel.org,
        AngeloGioacchino Del Regno 
        <angelogioacchino.delregno@...labora.com>,
        linux-arm-kernel@...ts.infradead.org,
        linux-mediatek@...ts.infradead.org,
        cros-qcom-dts-watchers@...omium.org,
        Andy Gross <agross@...nel.org>,
        Konrad Dybcio <konrad.dybcio@...aro.org>
Subject: Re: [PATCH 4/4] arm64: dts: qcom: sc7180: disable quad mode for spi nor

Hi,


On Tue, Aug 15, 2023 at 8:45 AM Hsin-Yi Wang <hsinyi@...omium.org> wrote:
>
> Some of the SKUs are using gigadevice gd25lq64c flash chip. The chip
> default enables quad mode, which results in the write protect pin set to
> IO pin. In trogdor platforms, we won't use quad enable for all SKUs, so
> apply the property to disable spi nor's quad mode.
>
> Signed-off-by: Hsin-Yi Wang <hsinyi@...omium.org>
> ---
>  arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi | 1 +
>  1 file changed, 1 insertion(+)
>
> diff --git a/arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi b/arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi
> index 5a33e16a8b677..0806ce8e86bea 100644
> --- a/arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi
> +++ b/arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi
> @@ -436,6 +436,7 @@ flash@0 {
>                 spi-max-frequency = <37500000>;
>                 spi-tx-bus-width = <2>;
>                 spi-rx-bus-width = <2>;
> +               disable-quad-mode;

This seems unnecessary. Unless "tx-bus-width" or "rx-bus-width" is 4
then Quad SPI isn't enabled. You don't need an explicit property since
this can just be inferred from the tx and rx bus width.

-Doug