Re: [PATCH] scsi: ufs: qcom: move ufs_qcom_host_reset() to ufs_qcom_device_reset()

[Can Guo]

On 10/25/2023 3:41 PM, Manivannan Sadhasivam wrote:
> On Tue, Oct 24, 2023 at 07:10:15PM +0800, Ziqi Chen wrote:
> > During PISI test, we found the issue that host Tx still bursting after
>
> What is PISI test?
>
> > H/W reset. Move ufs_qcom_host_reset() to ufs_qcom_device_reset() and
> > reset host before device reset to stop tx burst.
>
> device_reset() callback is supposed to reset only the device and not the host.
> So NACK for this patch.

Agree, the change should come in a more reasonable way.

Actually, similar code is already there in ufs_mtk_device_reset() in 
ufs-mediatek.c, I guess here is trying to mimic that fashion.

This change, from its functionality point of view, we do need it, 
because I occasionally (2 out of 10) hit PHY error on lane 0 during 
reboot test (in my case, I tried SM8350, SM8450 and SM8550， all same).

[    1.911188] [DEBUG]ufshcd_update_uic_error: UECPA:0x80000002
[    1.922843] [DEBUG]ufshcd_update_uic_error: UECDL:0x80004000
[    1.934473] [DEBUG]ufshcd_update_uic_error: UECN:0x0
[    1.944688] [DEBUG]ufshcd_update_uic_error: UECT:0x0
[    1.954901] [DEBUG]ufshcd_update_uic_error: UECDME:0x0

I found out that the PHY error pops out right after UFS device gets 
reset in the 2nd init. After having this change in place, the PA/DL 
errors are gone.

Thanks,
Can Guo.
> - Mani
>
> > Signed-off-by: Ziqi Chen <quic_ziqichen@xxxxxxxxxxx>
> > ---
> >   drivers/ufs/host/ufs-qcom.c | 13 +++++++------
> >   1 file changed, 7 insertions(+), 6 deletions(-)
> >
> > diff --git a/drivers/ufs/host/ufs-qcom.c b/drivers/ufs/host/ufs-qcom.c
> > index 96cb8b5..43163d3 100644
> > --- a/drivers/ufs/host/ufs-qcom.c
> > +++ b/drivers/ufs/host/ufs-qcom.c
> > @@ -445,12 +445,6 @@ static int ufs_qcom_power_up_sequence(struct ufs_hba *hba)
> >   	struct phy *phy = host->generic_phy;
> >   	int ret;
> >   
> > -	/* Reset UFS Host Controller and PHY */
> > -	ret = ufs_qcom_host_reset(hba);
> > -	if (ret)
> > -		dev_warn(hba->dev, "%s: host reset returned %d\n",
> > -				  __func__, ret);
> > -
> >   	/* phy initialization - calibrate the phy */
> >   	ret = phy_init(phy);
> >   	if (ret) {
> > @@ -1709,6 +1703,13 @@ static void ufs_qcom_dump_dbg_regs(struct ufs_hba *hba)
> >   static int ufs_qcom_device_reset(struct ufs_hba *hba)
> >   {
> >   	struct ufs_qcom_host *host = ufshcd_get_variant(hba);
> > +	int ret = 0;
> > +
> > +	/* Reset UFS Host Controller and PHY */
> > +	ret = ufs_qcom_host_reset(hba);
> > +	if (ret)
> > +		dev_warn(hba->dev, "%s: host reset returned %d\n",
> > +				  __func__, ret);
> >   
> >   	/* reset gpio is optional */
> >   	if (!host->device_reset)
> > --
> > 2.7.4