Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::3:3 as permitted sender) client-ip=2620:137:e000::3:3;
Date:   Fri, 8 Dec 2023 15:58:32 +0530
From:   Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
To:     Nitin Rawat <quic_nitirawa@quicinc.com>
Cc:     martin.petersen@oracle.com, jejb@linux.ibm.com,
        andersson@kernel.org, konrad.dybcio@linaro.org,
        linux-arm-msm@vger.kernel.org, linux-scsi@vger.kernel.org,
        linux-kernel@vger.kernel.org, quic_cang@quicinc.com,
        ahalaney@redhat.com
Subject: Re: [PATCH v2 05/17] scsi: ufs: qcom: Remove the warning message
 when core_reset is not available
Message-ID: <20231208102832.GA3008@thinkpad>
References: <20231208065902.11006-1-manivannan.sadhasivam@linaro.org>
 <20231208065902.11006-6-manivannan.sadhasivam@linaro.org>
 <7472fe73-e7a0-5c8c-6e85-655db028a5c3@quicinc.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Disposition: inline
Content-Transfer-Encoding: 8bit
In-Reply-To: <7472fe73-e7a0-5c8c-6e85-655db028a5c3@quicinc.com>
Precedence: bulk

On Fri, Dec 08, 2023 at 02:55:21PM +0530, Nitin Rawat wrote:
> 
> 
> On 12/8/2023 12:28 PM, Manivannan Sadhasivam wrote:
> > core_reset is optional, so there is no need to warn the user if it is not
> > available.
> > 
> > Reviewed-by: Andrew Halaney <ahalaney@redhat.com>
> > Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
> > ---
> >   drivers/ufs/host/ufs-qcom.c | 4 +---
> >   1 file changed, 1 insertion(+), 3 deletions(-)
> > 
> > diff --git a/drivers/ufs/host/ufs-qcom.c b/drivers/ufs/host/ufs-qcom.c
> > index dc93b1c5ca74..d474de0739e4 100644
> > --- a/drivers/ufs/host/ufs-qcom.c
> > +++ b/drivers/ufs/host/ufs-qcom.c
> > @@ -296,10 +296,8 @@ static int ufs_qcom_host_reset(struct ufs_hba *hba)
> >   	struct ufs_qcom_host *host = ufshcd_get_variant(hba);
> >   	bool reenable_intr;
> > -	if (!host->core_reset) {
> > -		dev_warn(hba->dev, "%s: reset control not set\n", __func__);
> > +	if (!host->core_reset)
> >   		return 0;
> > -	}
> >   	reenable_intr = hba->is_irq_enabled;
> >   	disable_irq(hba->irq);
> 
> 
> Hi Mani,
> 
> I think core reset is not frequent. It happen during only probe ,error
> handler.
> 
> core reset is needed in kernel to cleanup UFS phy and controller
> configuration before UFS HLOS operation starts as per HPG.
> 

This sounds like core reset is not an optional property but a required one. I
just checked the upstream DT files for all SoCs, and looks like pretty much all
of them support core reset.

Only MSM8996 doesn't have the reset property, but the reset is available in GCC.
So we should be able to use it in dtsi.

I also skimmed through the HPG and looks like core reset is not optional. Please
confirm.

- Mani

> Having existing warn print can be used to to debug or atleast know
> core_reset is missed in device tree to give indication complete reset hasn't
> been done and we could still be operating in bootloader configuration.
> 
> 
> Regards,
> Nitin
> 

-- 
மணிவண்ணன் சதாசிவம்