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Message-ID: <5850d5ac-e735-4358-866d-f410b00ba39d@acm.org>
Date:   Mon, 6 Nov 2023 09:56:23 -0800
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Subject: Re: [PATCH] dt-bindings: ufs: Add msi-parent for UFS MCQ
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To:     Rob Herring <robh@kernel.org>,
        Ziqi Chen <quic_ziqichen@quicinc.com>
Cc:     quic_asutoshd@quicinc.com, quic_cang@quicinc.com, mani@kernel.org,
        beanhuo@micron.com, avri.altman@wdc.com, junwoo80.lee@samsung.com,
        martin.petersen@oracle.com, quic_nguyenb@quicinc.com,
        quic_nitirawa@quicinc.com, quic_rampraka@quicinc.com,
        linux-scsi@vger.kernel.org, Alim Akhtar <alim.akhtar@samsung.com>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Conor Dooley <conor+dt@kernel.org>,
        Ulf Hansson <ulf.hansson@linaro.org>,
        Wolfram Sang <wsa@kernel.org>,
        Guenter Roeck <linux@roeck-us.net>,
        Miquel Raynal <miquel.raynal@bootlin.com>,
        Mark Brown <broonie@kernel.org>,
        "open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS" 
        <devicetree@vger.kernel.org>,
        open list <linux-kernel@vger.kernel.org>
References: <1698835699-28550-1-git-send-email-quic_ziqichen@quicinc.com>
 <20231106144831.GA317907-robh@kernel.org>
From:   Bart Van Assche <bvanassche@acm.org>
In-Reply-To: <20231106144831.GA317907-robh@kernel.org>
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On 11/6/23 06:48, Rob Herring wrote:
> On Wed, Nov 01, 2023 at 06:48:13PM +0800, Ziqi Chen wrote:
>> The Message Signaled Interrupts (MSI) has been introduced
>> to UFS driver since the MCQ be enabled.
> 
> Not really relevant when a driver supported MSI, but the when the h/w
> did. Has UFS always supported MSI? It was added in some version of the
> spec?

MSI support has been introduced in UFSHCI version 4.0 and I think that
the controller vendor can decide whether or not to implement MSI. Does
this mean that the patch needs to be improved?

Thanks,

Bart.