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Message-ID: <d198f09b-6b5f-42de-9331-30c6d2a12b67@quicinc.com>
Date:   Tue, 28 Nov 2023 15:58:42 +0800
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Subject: Re: [PATCH v5 07/10] scsi: ufs: ufs-qcom: Set initial PHY gear to max
 HS gear for HW ver 5 and newer
Content-Language: en-US
To:     Manivannan Sadhasivam <mani@kernel.org>
CC:     <bvanassche@acm.org>, <adrian.hunter@intel.com>,
        <beanhuo@micron.com>, <avri.altman@wdc.com>,
        <junwoo80.lee@samsung.com>, <martin.petersen@oracle.com>,
        <linux-scsi@vger.kernel.org>, <linux-arm-msm@vger.kernel.org>,
        Andy Gross <agross@kernel.org>,
        Bjorn Andersson <andersson@kernel.org>,
        Konrad Dybcio <konrad.dybcio@linaro.org>,
        "James E.J. Bottomley" <jejb@linux.ibm.com>,
        open list <linux-kernel@vger.kernel.org>
References: <1700729190-17268-1-git-send-email-quic_cang@quicinc.com>
 <1700729190-17268-8-git-send-email-quic_cang@quicinc.com>
 <20231128060046.GH3088@thinkpad>
From:   Can Guo <quic_cang@quicinc.com>
In-Reply-To: <20231128060046.GH3088@thinkpad>
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Hi Mani,

On 11/28/2023 2:00 PM, Manivannan Sadhasivam wrote:
> On Thu, Nov 23, 2023 at 12:46:27AM -0800, Can Guo wrote:
>> Set the initial PHY gear to max HS gear for hosts with HW ver 5 and newer.
>>
> 
> MAX_GEAR will be used for hosts with hw_ver.major >= 4

I put it > 5 because I am not intent to touch any old targets which has 
proven working fine with starting with PHY gear HS_G2. If I put it >= 4, 
there would be many targets impacted by this change. I need to go back 
and test those platforms (HW ver == 4).

Thanks,
Can Guo.

> 
>> This patch is not changing any functionalities or logic but only a
>> preparation patch for the next patch in this series.
>>
>> Signed-off-by: Can Guo <quic_cang@quicinc.com>
>> ---
>>   drivers/ufs/host/ufs-qcom.c | 21 +++++++++++++++------
>>   1 file changed, 15 insertions(+), 6 deletions(-)
>>
>> diff --git a/drivers/ufs/host/ufs-qcom.c b/drivers/ufs/host/ufs-qcom.c
>> index 6756f8d..7bbccf4 100644
>> --- a/drivers/ufs/host/ufs-qcom.c
>> +++ b/drivers/ufs/host/ufs-qcom.c
>> @@ -1067,6 +1067,20 @@ static void ufs_qcom_advertise_quirks(struct ufs_hba *hba)
>>   		hba->quirks |= UFSHCD_QUIRK_REINIT_AFTER_MAX_GEAR_SWITCH;
>>   }
>>   
>> +static void ufs_qcom_set_phy_gear(struct ufs_qcom_host *host)
>> +{
>> +	struct ufs_host_params *host_params = &host->host_params;
>> +
>> +	host->phy_gear = host_params->hs_tx_gear;
>> +
>> +	/*
>> +	 * Power up the PHY using the minimum supported gear (UFS_HS_G2).
>> +	 * Switching to max gear will be performed during reinit if supported.
> 
> You need to reword this comment too.
> 
>> +	 */
>> +	if (host->hw_ver.major < 0x5)
> 
> As I mentioned above, MAX_GEAR will be used if hw_ver.major is >=4 in
> ufs_qcom_get_hs_gear(). So this check should be (< 0x4).
> 
> - Mani
> 
>> +		host->phy_gear = UFS_HS_G2;
>> +}
>> +
>>   static void ufs_qcom_set_host_params(struct ufs_hba *hba)
>>   {
>>   	struct ufs_qcom_host *host = ufshcd_get_variant(hba);
>> @@ -1303,6 +1317,7 @@ static int ufs_qcom_init(struct ufs_hba *hba)
>>   	ufs_qcom_set_caps(hba);
>>   	ufs_qcom_advertise_quirks(hba);
>>   	ufs_qcom_set_host_params(hba);
>> +	ufs_qcom_set_phy_gear(host);
>>   
>>   	err = ufs_qcom_ice_init(host);
>>   	if (err)
>> @@ -1320,12 +1335,6 @@ static int ufs_qcom_init(struct ufs_hba *hba)
>>   		dev_warn(dev, "%s: failed to configure the testbus %d\n",
>>   				__func__, err);
>>   
>> -	/*
>> -	 * Power up the PHY using the minimum supported gear (UFS_HS_G2).
>> -	 * Switching to max gear will be performed during reinit if supported.
>> -	 */
>> -	host->phy_gear = UFS_HS_G2;
>> -
>>   	return 0;
>>   
>>   out_variant_clear:
>> -- 
>> 2.7.4
>>
>