| Message ID | 20240119185537.3091366-11-echanude@redhat.com |
|---|---|
| State | New |
| Headers | show |
| Series | scsi: ufs: qcom: avoid re-init quirk when gears match | expand |
On Fri, Jan 19, 2024 at 02:07:15PM -0600, Andrew Halaney wrote: > On Fri, Jan 19, 2024 at 01:55:47PM -0500, Eric Chanudet wrote: > > On sa8775p-ride, probing the hba will go through the > > UFSHCD_QUIRK_REINIT_AFTER_MAX_GEAR_SWITCH path although the power info > > are same during the second init. > > > > If the host is at least v4, ufs_qcom_get_hs_gear() picked the highest > > supported gear when setting the host_params. After the negotiation, if > > the host and device are on the same gear, it is the highest gear > > supported between the two. Skip the re-init to save some time. > > > > Signed-off-by: Eric Chanudet <echanude@redhat.com> > > --- > > > > "trace_event=ufs:ufshcd_init" reports the time spent where the re-init > > quirk is performed. On sa8775p-ride: > > Baseline: > > 0.355879: ufshcd_init: 1d84000.ufs: took 103377 usecs, dev_state: UFS_ACTIVE_PWR_MODE, link_state: UIC_LINK_ACTIVE_STATE, err 0 > > With this patch: > > 0.297676: ufshcd_init: 1d84000.ufs: took 43553 usecs, dev_state: UFS_ACTIVE_PWR_MODE, link_state: UIC_LINK_ACTIVE_STATE, err 0 > > > > drivers/ufs/host/ufs-qcom.c | 6 +++++- > > 1 file changed, 5 insertions(+), 1 deletion(-) > > > > diff --git a/drivers/ufs/host/ufs-qcom.c b/drivers/ufs/host/ufs-qcom.c > > index 39eef470f8fa..f9f161340e78 100644 > > --- a/drivers/ufs/host/ufs-qcom.c > > +++ b/drivers/ufs/host/ufs-qcom.c > > @@ -738,8 +738,12 @@ static int ufs_qcom_pwr_change_notify(struct ufs_hba *hba, > > * the second init can program the optimal PHY settings. This allows one to start > > * the first init with either the minimum or the maximum support gear. > > */ > > - if (hba->ufshcd_state == UFSHCD_STATE_RESET) > > + if (hba->ufshcd_state == UFSHCD_STATE_RESET) { > > + if (host->hw_ver.major >= 0x4 && > > Is this check really necessary? > > The initial phy_gear state is something like this (my phrasing of > ufs_qcom_set_phy_gear()): > > if hw_ver < 4: > # Comments about powering up with minimum gear (with no > # reasoning in the comment afaict), and mentions switching > # to higher gear in reinit quirk. This is opposite of the later > # versions which start at the max and scale down > phy_gear = UFS_HS_G2 > > else if hw_ver == 4: > phy_gear = hs_tx_gear # (so afaict always UFS_HS_G4) > > else if hw_ver >= 5: > phy_gear = hs_tx_gear # (What ever the max is for this version) > > if dev_major: > # Clears the reinit quirk in ufs_qcom_set_phy_gear() if the > # device version is provided by bootloader / controller > # because we already found it out and can init directly > # to the ideal gear > quirks &= ~UFSHCD_QUIRK_REINIT_AFTER_MAX_GEAR_SWITCH > > if dev_major < 4: > # Sets gear to UFS_HS_G4 to save power for UFS 3.1 and > # older devices > phy_gear = UFS_HS_G4 > > I guess what I'm saying is that I'm not totally seeing how this check > is dependent on the controller version. To me, if we're in the ideal > gear already and we know it, we should *not* reinit, no matter what the > controller version is. That's assuming there's not some other reasoning > for the quirk, but as far as I understand it the quirk exists because we > have to start with *some* phy gear value so we can talk to the device, > and once we discover what the device is capable of it makes sense to > scale down (or up for older controllers) to the ideal gear setting for > the attached device. Unfortunately to do the change we have to > reprogram the phy which I guess is only acceptable if we reprogram > everything (hence the reinit). > > Does that make sense or do you think I'm missing something? I think say > even for an older controller this makes sense, if its attached to a > UFS_HS_G2 capable device there is no reason to reinit since we started > up in the ideal configuration. I guess what I'm saying is shouldn't the check be something like: if (dev_req_params->gear_tx == host->phy_gear) { // Skip reinit since we started up in the agreed upon gear hba->quirks &= ~UFSHCD_QUIRK_REINIT_AFTER_MAX_GEAR_SWITCH; } Which is independent of the controller version? > > Thanks, > Andrew > > > + host_params->hs_tx_gear == dev_req_params->gear_tx) > > + hba->quirks &= ~UFSHCD_QUIRK_REINIT_AFTER_MAX_GEAR_SWITCH; > > host->phy_gear = dev_req_params->gear_tx; > > + } > > > > /* enable the device ref clock before changing to HS mode */ > > if (!ufshcd_is_hs_mode(&hba->pwr_info) && > > -- > > 2.43.0 > > > >
On Fri, Jan 19, 2024 at 04:33:10PM -0500, Eric Chanudet wrote: > On Fri, Jan 19, 2024 at 02:33:32PM -0600, Andrew Halaney wrote: > > On Fri, Jan 19, 2024 at 02:07:15PM -0600, Andrew Halaney wrote: > > > On Fri, Jan 19, 2024 at 01:55:47PM -0500, Eric Chanudet wrote: > > > > On sa8775p-ride, probing the hba will go through the > > > > UFSHCD_QUIRK_REINIT_AFTER_MAX_GEAR_SWITCH path although the power info > > > > are same during the second init. > > > > > > > > If the host is at least v4, ufs_qcom_get_hs_gear() picked the highest > > > > supported gear when setting the host_params. After the negotiation, if > > > > the host and device are on the same gear, it is the highest gear > > > > supported between the two. Skip the re-init to save some time. > > > > > > > > Signed-off-by: Eric Chanudet <echanude@redhat.com> > > > > --- > > > > > > > > "trace_event=ufs:ufshcd_init" reports the time spent where the re-init > > > > quirk is performed. On sa8775p-ride: > > > > Baseline: > > > > 0.355879: ufshcd_init: 1d84000.ufs: took 103377 usecs, dev_state: UFS_ACTIVE_PWR_MODE, link_state: UIC_LINK_ACTIVE_STATE, err 0 > > > > With this patch: > > > > 0.297676: ufshcd_init: 1d84000.ufs: took 43553 usecs, dev_state: UFS_ACTIVE_PWR_MODE, link_state: UIC_LINK_ACTIVE_STATE, err 0 > > > > > > > > drivers/ufs/host/ufs-qcom.c | 6 +++++- > > > > 1 file changed, 5 insertions(+), 1 deletion(-) > > > > > > > > diff --git a/drivers/ufs/host/ufs-qcom.c b/drivers/ufs/host/ufs-qcom.c > > > > index 39eef470f8fa..f9f161340e78 100644 > > > > --- a/drivers/ufs/host/ufs-qcom.c > > > > +++ b/drivers/ufs/host/ufs-qcom.c > > > > @@ -738,8 +738,12 @@ static int ufs_qcom_pwr_change_notify(struct ufs_hba *hba, > > > > * the second init can program the optimal PHY settings. This allows one to start > > > > * the first init with either the minimum or the maximum support gear. > > > > */ > > > > - if (hba->ufshcd_state == UFSHCD_STATE_RESET) > > > > + if (hba->ufshcd_state == UFSHCD_STATE_RESET) { > > > > + if (host->hw_ver.major >= 0x4 && > > > > > > Is this check really necessary? > > I *think* so. > > For example, if hw_ver < 4, ufs_qcom_set_phy_gear() has a comment saying > "power up the PHY using minimum supported gear (UFS_HS_G2). Switching to > max gear will be performed during reinit if supported." > > > > > > > The initial phy_gear state is something like this (my phrasing of > > > ufs_qcom_set_phy_gear()): > > > > > > if hw_ver < 4: > > > # Comments about powering up with minimum gear (with no > > > # reasoning in the comment afaict), and mentions switching > > > # to higher gear in reinit quirk. This is opposite of the later > > > # versions which start at the max and scale down > > > phy_gear = UFS_HS_G2 > > IIUC, the device would not be able to negotiate a gear higher than the > minimum set for the phy_gear on initialization. > > ufshcd_init_host_params() and ufs_qcom_get_hs_gear() both set the > controller <v4 host_params to G3. So if the device is HS capable, the > re-init would set G3, instead of the G2 selected by > ufs_qcom_set_phy_gear(). > REINIT quirk is applicable for controllers starting from v4 only, because legacy controllers don't need separate PHY init sequences. So you can get rid of that check. - Mani
On Fri, Jan 19, 2024 at 01:55:47PM -0500, Eric Chanudet wrote: > On sa8775p-ride, probing the hba will go through the > UFSHCD_QUIRK_REINIT_AFTER_MAX_GEAR_SWITCH path although the power info > are same during the second init. > > If the host is at least v4, ufs_qcom_get_hs_gear() picked the highest > supported gear when setting the host_params. After the negotiation, if > the host and device are on the same gear, it is the highest gear > supported between the two. Skip the re-init to save some time. > > Signed-off-by: Eric Chanudet <echanude@redhat.com> > --- > > "trace_event=ufs:ufshcd_init" reports the time spent where the re-init > quirk is performed. On sa8775p-ride: > Baseline: > 0.355879: ufshcd_init: 1d84000.ufs: took 103377 usecs, dev_state: UFS_ACTIVE_PWR_MODE, link_state: UIC_LINK_ACTIVE_STATE, err 0 > With this patch: > 0.297676: ufshcd_init: 1d84000.ufs: took 43553 usecs, dev_state: UFS_ACTIVE_PWR_MODE, link_state: UIC_LINK_ACTIVE_STATE, err 0 > > drivers/ufs/host/ufs-qcom.c | 6 +++++- > 1 file changed, 5 insertions(+), 1 deletion(-) > > diff --git a/drivers/ufs/host/ufs-qcom.c b/drivers/ufs/host/ufs-qcom.c > index 39eef470f8fa..f9f161340e78 100644 > --- a/drivers/ufs/host/ufs-qcom.c > +++ b/drivers/ufs/host/ufs-qcom.c > @@ -738,8 +738,12 @@ static int ufs_qcom_pwr_change_notify(struct ufs_hba *hba, > * the second init can program the optimal PHY settings. This allows one to start > * the first init with either the minimum or the maximum support gear. > */ > - if (hba->ufshcd_state == UFSHCD_STATE_RESET) > + if (hba->ufshcd_state == UFSHCD_STATE_RESET) { > + if (host->hw_ver.major >= 0x4 && You can get rid of this check as I said in the reply. > + host_params->hs_tx_gear == dev_req_params->gear_tx) How about? /* * Skip REINIT if the negotiated gear matches with the * initial phy_gear. Otherwise, update the phy_gear to * program the optimal gear setting during REINIT. */ if (host->phy_gear == dev_req_params->gear_tx) hba->quirks &= ~UFSHCD_QUIRK_REINIT_AFTER_MAX_GEAR_SWITCH; else host->phy_gear = dev_req_params->gear_tx; - Mani > + hba->quirks &= ~UFSHCD_QUIRK_REINIT_AFTER_MAX_GEAR_SWITCH; > host->phy_gear = dev_req_params->gear_tx; > + } > > /* enable the device ref clock before changing to HS mode */ > if (!ufshcd_is_hs_mode(&hba->pwr_info) && > -- > 2.43.0 >
diff --git a/drivers/ufs/host/ufs-qcom.c b/drivers/ufs/host/ufs-qcom.c index 39eef470f8fa..f9f161340e78 100644 --- a/drivers/ufs/host/ufs-qcom.c +++ b/drivers/ufs/host/ufs-qcom.c @@ -738,8 +738,12 @@ static int ufs_qcom_pwr_change_notify(struct ufs_hba *hba, * the second init can program the optimal PHY settings. This allows one to start * the first init with either the minimum or the maximum support gear. */ - if (hba->ufshcd_state == UFSHCD_STATE_RESET) + if (hba->ufshcd_state == UFSHCD_STATE_RESET) { + if (host->hw_ver.major >= 0x4 && + host_params->hs_tx_gear == dev_req_params->gear_tx) + hba->quirks &= ~UFSHCD_QUIRK_REINIT_AFTER_MAX_GEAR_SWITCH; host->phy_gear = dev_req_params->gear_tx; + } /* enable the device ref clock before changing to HS mode */ if (!ufshcd_is_hs_mode(&hba->pwr_info) &&
On sa8775p-ride, probing the hba will go through the UFSHCD_QUIRK_REINIT_AFTER_MAX_GEAR_SWITCH path although the power info are same during the second init. If the host is at least v4, ufs_qcom_get_hs_gear() picked the highest supported gear when setting the host_params. After the negotiation, if the host and device are on the same gear, it is the highest gear supported between the two. Skip the re-init to save some time. Signed-off-by: Eric Chanudet <echanude@redhat.com> --- "trace_event=ufs:ufshcd_init" reports the time spent where the re-init quirk is performed. On sa8775p-ride: Baseline: 0.355879: ufshcd_init: 1d84000.ufs: took 103377 usecs, dev_state: UFS_ACTIVE_PWR_MODE, link_state: UIC_LINK_ACTIVE_STATE, err 0 With this patch: 0.297676: ufshcd_init: 1d84000.ufs: took 43553 usecs, dev_state: UFS_ACTIVE_PWR_MODE, link_state: UIC_LINK_ACTIVE_STATE, err 0 drivers/ufs/host/ufs-qcom.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)