linux-kernel - Re: [PATCH 2/2] media: platform: mtk-mdp3: Use devicetree phandle to retrieve SCP

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: <CAGb2v66rEqWBjdMNO3VMZhYj36hhKTxPk+9pborPjnqW0B-=ZA@mail.gmail.com>
Date:   Tue, 19 Sep 2023 18:21:53 +0800
From:   Chen-Yu Tsai <wens@...nel.org>
To:     AngeloGioacchino Del Regno 
        <angelogioacchino.delregno@...labora.com>
Cc:     mchehab@...nel.org, robh+dt@...nel.org,
        krzysztof.kozlowski+dt@...aro.org, conor+dt@...nel.org,
        matthias.bgg@...il.com, moudy.ho@...iatek.com,
        hverkuil-cisco@...all.nl, sakari.ailus@...ux.intel.com,
        u.kleine-koenig@...gutronix.de, linqiheng@...wei.com,
        linux-media@...r.kernel.org, devicetree@...r.kernel.org,
        linux-kernel@...r.kernel.org, linux-arm-kernel@...ts.infradead.org,
        linux-mediatek@...ts.infradead.org, kernel@...labora.com,
        wenst@...omium.org
Subject: Re: [PATCH 2/2] media: platform: mtk-mdp3: Use devicetree phandle to
 retrieve SCP

On Tue, Sep 19, 2023 at 6:00 PM AngeloGioacchino Del Regno
<angelogioacchino.delregno@...labora.com> wrote:
>
> Instead of walking the entire parent node for something that has the
> right compatible, use the scp_get() function provided by the MediaTek
> SCP remoteproc driver to retrieve a handle to mtk_scp through the
> devicetree "mediatek,scp" (phandle) property.
>
> In case of multi-core SCP, this also allows to select a specific core.
>
> Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@...labora.com>
> ---
>  .../media/platform/mediatek/mdp3/mtk-mdp3-core.c | 16 ++++++++++------
>  1 file changed, 10 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/media/platform/mediatek/mdp3/mtk-mdp3-core.c b/drivers/media/platform/mediatek/mdp3/mtk-mdp3-core.c
> index 8677e7fd5083..d93d3833633e 100644
> --- a/drivers/media/platform/mediatek/mdp3/mtk-mdp3-core.c
> +++ b/drivers/media/platform/mediatek/mdp3/mtk-mdp3-core.c
> @@ -254,13 +254,17 @@ static int mdp_probe(struct platform_device *pdev)
>                 goto err_destroy_job_wq;
>         }
>
> -       mm_pdev = __get_pdev_by_id(pdev, NULL, MDP_INFRA_SCP);
> -       if (WARN_ON(!mm_pdev)) {
> -               dev_err(&pdev->dev, "Could not get scp device\n");
> -               ret = -ENODEV;
> -               goto err_destroy_clock_wq;
> +       mdp->scp = scp_get(pdev);
> +       if (!mdp->scp) {
> +               mm_pdev = __get_pdev_by_id(pdev, NULL, MDP_INFRA_SCP);
> +               if (WARN_ON(!mm_pdev)) {
> +                       dev_err(&pdev->dev, "Could not get scp device\n");
> +                       ret = -ENODEV;
> +                       goto err_destroy_clock_wq;
> +               }
> +               mdp->scp = platform_get_drvdata(mm_pdev);

You need to keep the original code as a fallback for old device trees.

ChenYu

>         }
> -       mdp->scp = platform_get_drvdata(mm_pdev);
> +
>         mdp->rproc_handle = scp_get_rproc(mdp->scp);
>         dev_dbg(&pdev->dev, "MDP rproc_handle: %pK", mdp->rproc_handle);
>
> --
> 2.42.0
>