linux-kernel - Re: [EXT] Re: [PATCH v4 1/2] arm64: dts: imx8-ss-img: Assign slot for imx jpeg encoder/decoder

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: <2665f382-3df9-441e-bdb5-205a3466dd35@linaro.org>
Date:   Thu, 28 Sep 2023 07:02:59 +0200
From:   Krzysztof Kozlowski <krzysztof.kozlowski@...aro.org>
To:     Ming Qian <ming.qian@....com>,
        "Mirela Rabulea (OSS)" <mirela.rabulea@....nxp.com>,
        "robh+dt@...nel.org" <robh+dt@...nel.org>,
        "shawnguo@...nel.org" <shawnguo@...nel.org>
Cc:     "krzysztof.kozlowski+dt@...aro.org" 
        <krzysztof.kozlowski+dt@...aro.org>,
        "conor+dt@...nel.org" <conor+dt@...nel.org>,
        "mchehab@...nel.org" <mchehab@...nel.org>,
        "hverkuil-cisco@...all.nl" <hverkuil-cisco@...all.nl>,
        "s.hauer@...gutronix.de" <s.hauer@...gutronix.de>,
        "kernel@...gutronix.de" <kernel@...gutronix.de>,
        "festevam@...il.com" <festevam@...il.com>,
        "X.H. Bao" <xiahong.bao@....com>, Eagle Zhou <eagle.zhou@....com>,
        Tao Jiang <tao.jiang_2@....com>,
        dl-linux-imx <linux-imx@....com>,
        "devicetree@...r.kernel.org" <devicetree@...r.kernel.org>,
        "linux-media@...r.kernel.org" <linux-media@...r.kernel.org>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        "linux-arm-kernel@...ts.infradead.org" 
        <linux-arm-kernel@...ts.infradead.org>
Subject: Re: [EXT] Re: [PATCH v4 1/2] arm64: dts: imx8-ss-img: Assign slot for
 imx jpeg encoder/decoder

On 27/09/2023 11:19, Ming Qian wrote:
>> From: Krzysztof Kozlowski <krzysztof.kozlowski@...aro.org>
>> Sent: 2023年9月27日 16:11
>> To: Ming Qian <ming.qian@....com>; Mirela Rabulea (OSS)
>> <mirela.rabulea@....nxp.com>; robh+dt@...nel.org; shawnguo@...nel.org
>> Cc: krzysztof.kozlowski+dt@...aro.org; conor+dt@...nel.org;
>> mchehab@...nel.org; hverkuil-cisco@...all.nl; s.hauer@...gutronix.de;
>> kernel@...gutronix.de; festevam@...il.com; X.H. Bao
>> <xiahong.bao@....com>; Eagle Zhou <eagle.zhou@....com>; Tao Jiang
>> <tao.jiang_2@....com>; dl-linux-imx <linux-imx@....com>;
>> devicetree@...r.kernel.org; linux-media@...r.kernel.org; linux-
>> kernel@...r.kernel.org; linux-arm-kernel@...ts.infradead.org
>> Subject: [EXT] Re: [PATCH v4 1/2] arm64: dts: imx8-ss-img: Assign slot for imx
>> jpeg encoder/decoder
>>
>> Caution: This is an external email. Please take care when clicking links or
>> opening attachments. When in doubt, report the message using the 'Report
>> this email' button
>>
>>
>> On 26/09/2023 12:09, Ming Qian wrote:
>>> There are total 4 slots available in the IP, and we only need to use
>>> one slot in one os, assign a single slot for imx jpeg device node,
>>> configure interrupt and power domain only for 1 slot, not for the all 4 slots.
>>
>> DTS is independent of OS, so same DTS will be used by two OSes. This patch is
>> not correct in that matter. Explanation is not proper justification.
>>
> 
> Hi Krzysztof,
> 
> I agree that DTS is independent of OS, otherwise we need to choose the slot index by hard code in driver.
> I think it's just the reason why we need this patch.
> We have different platforms that use this IP, we need to configure the slot in dts.

I still do not know what is the "slot". VM partitioning? Some pinmux
configuration?

Other platforms will use the same DTS, so the same slot and you are back
at the same problem... DTS should be the full description of the
hardware, thus removing interrupts is not "full description" anymore.

> 
> Would you please give some guide about proper justification?
Describe architecture and then propose generic solution matching
multiple vendors and IP blocks, not something solving only this one problem.

Best regards,
Krzysztof