Hi, I think content is lacking in the UFSHCI spec. In the process, AH8 is in operation, and it seems that sending the command hibern8 by manual has a defeat. I don't know what the all hci vendor's hardware design will be, but there is a possibility that ah8 and manual hibern8 may overlap. So if is operating in ah8, it is thought that it will be safer to disable ah8 before sending hibern8 command. > -----Original Message----- > From: Stanley Chu [mailto:stanley.chu@xxxxxxxxxxxx] > Sent: Wednesday, January 26, 2022 10:22 AM > To: SEO HOYOUNG; linux-scsi@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; > alim.akhtar@xxxxxxxxxxx; avri.altman@xxxxxxx; jejb@xxxxxxxxxxxxx; > martin.petersen@xxxxxxxxxx; beanhuo@xxxxxxxxxx; asutoshd@xxxxxxxxxxxxxx; > cang@xxxxxxxxxxxxxx; bvanassche@xxxxxxx; bhoon95.kim@xxxxxxxxxxx; > kwmad.kim@xxxxxxxxxxx > Cc: kernel test robot; peter.wang@xxxxxxxxxxxx > Subject: Re: [PATCH v2] scsi: ufs: disable auto hibern8 while entering > suspend > > Hi Hoyoung, > > On Tue, 2022-01-25 at 03:06 +0900, SEO HOYOUNG wrote: > > v1-> v2: fixed no previous prototype warning > > Reported-by: kernel test robot <lkp@xxxxxxxxx> > > > > All warnings (new ones prefixed by >>): > > > > drivers/scsi/ufs/ufshcd.c:4207:6: warning: no previous prototype > > > > for 'ufshcd_auto_hibern8_disable' [-Wmissing-prototypes] > > 4207 | void ufshcd_auto_hibern8_disable(struct ufs_hba *hba) > > > > If using auto hibern8 mode, need to disable auto hibern8 while > > entering suspend. > > When using auto hibern8 mode, it does not seem right to send a uic > > command > > The UFSHCI spec does not mention the above rule. > Why would you need to disable AH8 before using UIC command to enter H8? > > > for entry into hibern8 in the next > > line(ufshcd_lik_state_transition(..)) > > It seem right to send after disable auto hibern8. > > > > In addition, if the auto hibern8 mode supported, it is enabled in > > resume. > > So it seems that it will be paired only when auto hibern8 is disabled > > while entering suspend. > > > > Signed-off-by: SEO HOYOUNG <hy50.seo@xxxxxxxxxxx> > > --- > > drivers/scsi/ufs/ufshcd.c | 14 ++++++++++++++ > > 1 file changed, 14 insertions(+) > > > > diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c > > index 460d2b440d2e..a6edbbd8ca2c 100644 > > --- a/drivers/scsi/ufs/ufshcd.c > > +++ b/drivers/scsi/ufs/ufshcd.c > > @@ -254,6 +254,7 @@ static void > > ufshcd_wb_toggle_flush_during_h8(struct ufs_hba *hba, bool set); > > static inline void ufshcd_wb_toggle_flush(struct ufs_hba *hba, bool > > enable); static void ufshcd_hba_vreg_set_lpm(struct ufs_hba *hba); > > static void ufshcd_hba_vreg_set_hpm(struct ufs_hba *hba); > > +static void ufshcd_auto_hibern8_disable(struct ufs_hba *hba); > > > > static inline void ufshcd_enable_irq(struct ufs_hba *hba) { @@ > > -4204,6 +4205,18 @@ void ufshcd_auto_hibern8_update(struct ufs_hba > > *hba, u32 ahit) } EXPORT_SYMBOL_GPL(ufshcd_auto_hibern8_update); > > > > +static void ufshcd_auto_hibern8_disable(struct ufs_hba *hba) { > > + unsigned long flags; > > + > > + if (!ufshcd_is_auto_hibern8_supported(hba)) > > + return; > > + > > + spin_lock_irqsave(hba->host->host_lock, flags); > > + ufshcd_writel(hba, 0, REG_AUTO_HIBERNATE_IDLE_TIMER); > > + spin_unlock_irqrestore(hba->host->host_lock, flags); } > > + > > void ufshcd_auto_hibern8_enable(struct ufs_hba *hba) { > > unsigned long flags; > > @@ -8925,6 +8938,7 @@ static int __ufshcd_wl_suspend(struct ufs_hba > > *hba, enum ufs_pm_op pm_op) > > * with the link off, so do not check for bkops. > > */ > > check_for_bkops = !ufshcd_is_ufs_dev_deepsleep(hba); > > + ufshcd_auto_hibern8_disable(hba); > > ret = ufshcd_link_state_transition(hba, req_link_state, > > check_for_bkops); > > if (ret) > > goto set_dev_active;
