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Message-ID: <60cd9300-d022-65a2-2804-1539a648b3a4@quicinc.com>
Date: Wed, 22 May 2024 22:34:14 -0700
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Subject: Re: [PATCH v1 2/2] scsi: ufs: qcom: Update the UIC Command Timeout
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To: Bart Van Assche <bvanassche@acm.org>, <quic_cang@quicinc.com>,
        <quic_nitirawa@quicinc.com>, <avri.altman@wdc.com>,
        <beanhuo@micron.com>, <adrian.hunter@intel.com>,
        <martin.petersen@oracle.com>
CC: <linux-scsi@vger.kernel.org>, Bjorn Andersson <andersson@kernel.org>,
        Konrad Dybcio <konrad.dybcio@linaro.org>,
        Manivannan Sadhasivam
	<manivannan.sadhasivam@linaro.org>,
        "James E.J. Bottomley"
	<jejb@linux.ibm.com>,
        "open list:ARM/QUALCOMM SUPPORT"
	<linux-arm-msm@vger.kernel.org>,
        open list <linux-kernel@vger.kernel.org>
References: <cover.1716359578.git.quic_nguyenb@quicinc.com>
 <8e5593feaac75660ff132d67ee5d9130e628fefb.1716359578.git.quic_nguyenb@quicinc.com>
 <2ec8a7a6-c2cd-4861-9a43-8a4652e0f116@acm.org>
 <f9595b82-66f9-dce2-7fba-c42b1eacf962@quicinc.com>
 <bdd52dc0-85dd-4000-b5dd-c2c22f5b8ba1@acm.org>
From: "Bao D. Nguyen" <quic_nguyenb@quicinc.com>
In-Reply-To: <bdd52dc0-85dd-4000-b5dd-c2c22f5b8ba1@acm.org>
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On 5/22/2024 2:01 PM, Bart Van Assche wrote:
> On 5/22/24 13:56, Bao D. Nguyen wrote:
>> On 5/22/2024 11:18 AM, Bart Van Assche wrote:
>>> Since the described issue is only encountered during development, why to
>>> modify the UIC command timeout unconditionally?
>>
>> The vendors can enjoy the default 500ms UIC timeout if they prefer.
>> As long as they don't write to hba->uic_cmd_timeout in the vendor's 
>> initialization routine, the default value of 500ms will be used.
> 
> Since this issue is not vendor specific, I think it would be better to
> modify the UFSHCI core driver only. Has it been considered to introduce a
> kernel module parameter for setting the UIC command timeout instead of the
> approach of this patch? As you probably know there are multiple mechanisms
> for specifying kernel module parameters, e.g. the bootargs parameter in the
> device tree.

The proposal here uses similar implementation as the auto hibern8 timer 
(hba->ahit). The ahit mechanism has been working well and stable, so I 
thought why not keep using it? Let see if other members have any 
comments about kernel module parameter/bootargs suggestion.

Thanks, Bao

> 
> Thanks,
> 
> Bart.
>