Re: [PATCH v6 03/10] scsi: ufs: add quirk to enable host controller without hce

[Can Guo <cang@xxxxxxxxxxxxxx>]

On 2020-04-21 13:59, Can Guo wrote:
> On 2020-04-18 01:59, Alim Akhtar wrote:
> > Some host controllers don't support host controller enable via HCE.
> >
> > Signed-off-by: Seungwon Jeon <essuuj@xxxxxxxxx>
> > Signed-off-by: Alim Akhtar <alim.akhtar@xxxxxxxxxxx>
>
> They are back again finally...
>
> Reviewd-by: Can Guo <cang@xxxxxxxxxxxxxx>

Reviewed-by: Can Guo <cang@xxxxxxxxxxxxxx>

> > ---
> >  drivers/scsi/ufs/ufshcd.c | 76 
> > +++++++++++++++++++++++++++++++++++++--
> >  drivers/scsi/ufs/ufshcd.h |  6 ++++
> >  2 files changed, 80 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
> > index 0e9704da58bd..ee30ed6cc805 100644
> > --- a/drivers/scsi/ufs/ufshcd.c
> > +++ b/drivers/scsi/ufs/ufshcd.c
> > @@ -3534,6 +3534,52 @@ static int ufshcd_dme_link_startup(struct 
> > ufs_hba *hba)
> >  			"dme-link-startup: error code %d\n", ret);
> >  	return ret;
> >  }
> > +/**
> > + * ufshcd_dme_reset - UIC command for DME_RESET
> > + * @hba: per adapter instance
> > + *
> > + * DME_RESET command is issued in order to reset UniPro stack.
> > + * This function now deal with cold reset.
> > + *
> > + * Returns 0 on success, non-zero value on failure
> > + */
> > +static int ufshcd_dme_reset(struct ufs_hba *hba)
> > +{
> > +	struct uic_command uic_cmd = {0};
> > +	int ret;
> > +
> > +	uic_cmd.command = UIC_CMD_DME_RESET;
> > +
> > +	ret = ufshcd_send_uic_cmd(hba, &uic_cmd);
> > +	if (ret)
> > +		dev_err(hba->dev,
> > +			"dme-reset: error code %d\n", ret);
> > +
> > +	return ret;
> > +}
> > +
> > +/**
> > + * ufshcd_dme_enable - UIC command for DME_ENABLE
> > + * @hba: per adapter instance
> > + *
> > + * DME_ENABLE command is issued in order to enable UniPro stack.
> > + *
> > + * Returns 0 on success, non-zero value on failure
> > + */
> > +static int ufshcd_dme_enable(struct ufs_hba *hba)
> > +{
> > +	struct uic_command uic_cmd = {0};
> > +	int ret;
> > +
> > +	uic_cmd.command = UIC_CMD_DME_ENABLE;
> > +
> > +	ret = ufshcd_send_uic_cmd(hba, &uic_cmd);
> > +	if (ret)
> > +		dev_err(hba->dev,
> > +			"dme-reset: error code %d\n", ret);
> > +
> > +	return ret;
> > +}
> >
> >  static inline void ufshcd_add_delay_before_dme_cmd(struct ufs_hba 
> > *hba)
> >  {
> > @@ -4251,7 +4297,7 @@ static inline void ufshcd_hba_stop(struct
> > ufs_hba *hba, bool can_sleep)
> >  }
> >
> >  /**
> > - * ufshcd_hba_enable - initialize the controller
> > + * ufshcd_hba_execute_hce - initialize the controller
> >   * @hba: per adapter instance
> >   *
> >   * The controller resets itself and controller firmware 
> > initialization
> > @@ -4260,7 +4306,7 @@ static inline void ufshcd_hba_stop(struct
> > ufs_hba *hba, bool can_sleep)
> >   *
> >   * Returns 0 on success, non-zero value on failure
> >   */
> > -int ufshcd_hba_enable(struct ufs_hba *hba)
> > +static int ufshcd_hba_execute_hce(struct ufs_hba *hba)
> >  {
> >  	int retry;
> >
> > @@ -4308,6 +4354,32 @@ int ufshcd_hba_enable(struct ufs_hba *hba)
> >
> >  	return 0;
> >  }
> > +
> > +int ufshcd_hba_enable(struct ufs_hba *hba)
> > +{
> > +	int ret;
> > +
> > +	if (hba->quirks & UFSHCI_QUIRK_BROKEN_HCE) {
> > +		ufshcd_set_link_off(hba);
> > +		ufshcd_vops_hce_enable_notify(hba, PRE_CHANGE);
> > +
> > +		/* enable UIC related interrupts */
> > +		ufshcd_enable_intr(hba, UFSHCD_UIC_MASK);
> > +		ret = ufshcd_dme_reset(hba);
> > +		if (!ret) {
> > +			ret = ufshcd_dme_enable(hba);
> > +			if (!ret)
> > +				ufshcd_vops_hce_enable_notify(hba, POST_CHANGE);
> > +			if (ret)
> > +				dev_err(hba->dev,
> > +					"Host controller enable failed with non-hce\n");
> > +		}
> > +	} else {
> > +		ret = ufshcd_hba_execute_hce(hba);
> > +	}
> > +
> > +	return ret;
> > +}
> >  EXPORT_SYMBOL_GPL(ufshcd_hba_enable);
> >
> >  static int ufshcd_disable_tx_lcc(struct ufs_hba *hba, bool peer)
> > diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
> > index 53096642f9a8..f8d08cb9caf7 100644
> > --- a/drivers/scsi/ufs/ufshcd.h
> > +++ b/drivers/scsi/ufs/ufshcd.h
> > @@ -529,6 +529,12 @@ enum ufshcd_quirks {
> >  	 * that the interrupt aggregation timer and counter are reset by 
> > s/w.
> >  	 */
> >  	UFSHCI_QUIRK_SKIP_RESET_INTR_AGGR		= 1 << 7,
> > +
> > +	/*
> > +	 * This quirks needs to be enabled if host controller cannot be
> > +	 * enabled via HCE register.
> > +	 */
> > +	UFSHCI_QUIRK_BROKEN_HCE				= 1 << 8,
> >  };
> >
> >  enum ufshcd_caps {