Re: [EXT] [PATCH v1 1/2] scsi: ufs: Introduce a vops for resetting host controller

[cang@xxxxxxxxxxxxxx]

On 2019-10-23 18:39, Bean Huo (beanhuo) wrote:
> Hi, Can Guo
> Actually, we already have DME_RESET,  this is not enough for Qualcomm 
> host?
> Thanks,
>
> //Bean

Hi Bean,

Yes, for Qualcomm hosts, we need this to fully reset the whole UFS 
controller block

Can Guo

> > Some UFS host controllers need their specific implementations of 
> > resetting to
> > get them into a good state. Provide a new vops to allow the platform 
> > driver to
> > implement this own reset operation.
> >
> > Signed-off-by: Can Guo <cang@xxxxxxxxxxxxxx>
> > ---
> >  drivers/scsi/ufs/ufshcd.c | 16 ++++++++++++++++  
> > drivers/scsi/ufs/ufshcd.h | 10
> > ++++++++++
> >  2 files changed, 26 insertions(+)
> >
> > diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c 
> > index
> > c28c144..161e3c4 100644
> > --- a/drivers/scsi/ufs/ufshcd.c
> > +++ b/drivers/scsi/ufs/ufshcd.c
> > @@ -3859,6 +3859,14 @@ static int ufshcd_link_recovery(struct ufs_hba 
> > *hba)
> >  	ufshcd_set_eh_in_progress(hba);
> >  	spin_unlock_irqrestore(hba->host->host_lock, flags);
> >
> > +	ret = ufshcd_vops_full_reset(hba);
> > +	if (ret)
> > +		dev_warn(hba->dev, "%s: full reset returned %d\n",
> > +				  __func__, ret);
> > +
> > +	/* Reset the attached device */
> > +	ufshcd_vops_device_reset(hba);
> > +
> >  	ret = ufshcd_host_reset_and_restore(hba);
> >
> >  	spin_lock_irqsave(hba->host->host_lock, flags); @@ -6241,6 +6249,11
> > @@ static int ufshcd_reset_and_restore(struct ufs_hba *hba)
> >  	int retries = MAX_HOST_RESET_RETRIES;
> >
> >  	do {
> > +		err = ufshcd_vops_full_reset(hba);
> > +		if (err)
> > +			dev_warn(hba->dev, "%s: full reset returned %d\n",
> > +					__func__, err);
> > +
> >  		/* Reset the attached device */
> >  		ufshcd_vops_device_reset(hba);
> >
> > @@ -8384,6 +8397,9 @@ int ufshcd_init(struct ufs_hba *hba, void 
> > __iomem
> > *mmio_base, unsigned int irq)
> >  		goto exit_gating;
> >  	}
> >
> > +	/* Reset controller to power on reset (POR) state */
> > +	ufshcd_vops_full_reset(hba);
> > +
> >  	/* Reset the attached device */
> >  	ufshcd_vops_device_reset(hba);
> >
> > diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h 
> > index
> > e0fe247..253b9ea 100644
> > --- a/drivers/scsi/ufs/ufshcd.h
> > +++ b/drivers/scsi/ufs/ufshcd.h
> > @@ -296,6 +296,8 @@ struct ufs_pwr_mode_info {
> >   * @apply_dev_quirks: called to apply device specific quirks
> >   * @suspend: called during host controller PM callback
> >   * @resume: called during host controller PM callback
> > + * @full_reset: called for handling variant specific implementations 
> > of
> > + *              resetting the hci
> >   * @dbg_register_dump: used to dump controller debug information
> >   * @phy_initialization: used to initialize phys
> >   * @device_reset: called to issue a reset pulse on the UFS device @@ 
> > -325,6
> > +327,7 @@ struct ufs_hba_variant_ops {
> >  	int	(*apply_dev_quirks)(struct ufs_hba *);
> >  	int     (*suspend)(struct ufs_hba *, enum ufs_pm_op);
> >  	int     (*resume)(struct ufs_hba *, enum ufs_pm_op);
> > +	int	(*full_reset)(struct ufs_hba *hba);
> >  	void	(*dbg_register_dump)(struct ufs_hba *hba);
> >  	int	(*phy_initialization)(struct ufs_hba *);
> >  	void	(*device_reset)(struct ufs_hba *hba);
> > @@ -1076,6 +1079,13 @@ static inline int ufshcd_vops_resume(struct 
> > ufs_hba
> > *hba, enum ufs_pm_op op)
> >  	return 0;
> >  }
> >
> > +static inline int ufshcd_vops_full_reset(struct ufs_hba *hba) {
> > +	if (hba->vops && hba->vops->full_reset)
> > +		return hba->vops->full_reset(hba);
> > +	return 0;
> > +}
> > +
> >  static inline void ufshcd_vops_dbg_register_dump(struct ufs_hba *hba) 
> >  {
> >  	if (hba->vops && hba->vops->dbg_register_dump)
> > --
> > The Qualcomm Innovation Center, Inc. is a member of the Code Aurora 
> > Forum,
> > a Linux Foundation Collaborative Project