| Message ID | 20250410090102.20781-1-quic_nitirawa@quicinc.com |
|---|---|
| Headers | show |
| Series | Refactor phy powerup sequence | expand |
On 4/11/2025 1:35 AM, Dmitry Baryshkov wrote: > On Thu, Apr 10, 2025 at 02:30:53PM +0530, Nitin Rawat wrote: >> In Current code regulators enable, clks enable, calibrating UFS PHY, >> start_serdes and polling PCS_ready_status are part of phy_power_on. >> >> UFS PHY registers are retained after power collapse, meaning calibrating >> UFS PHY, start_serdes and polling PCS_ready_status can be done only when >> hba is powered_on, and not needed every time when phy_power_on is called >> during resume. Hence keep the code which enables PHY's regulators & clks >> in phy_power_on and move the rest steps into phy_calibrate function. >> >> Since phy_power_on is separated out from phy calibrate, make separate calls >> to phy_power_on and phy_calibrate calls from ufs qcom driver. >> >> Also for better power saving, remove the phy_power_on/off calls from >> resume/suspend path and put them to ufs_qcom_setup_clocks, so that >> PHY's regulators & clks can be turned on/off along with UFS's clocks. > > Please add an explicit note that patch1 is a requirement for the rest of > the PHY patches. It might make sense to merge it through the PHY tree > too (or to use an immutable branch). > Hi Dmitry, Thanks for the suggestion. Sure I would mention this in the cover letter when I post next patchset. Thanks, Nitin >> >> This patch series is tested on SM8550 QRD, SM8650 MTP , SM8750 MTP. >> >
On Fri, 11 Apr 2025 at 13:50, Nitin Rawat <quic_nitirawa@quicinc.com> wrote: > > > > On 4/11/2025 1:38 AM, Dmitry Baryshkov wrote: > > On Thu, Apr 10, 2025 at 02:30:57PM +0530, Nitin Rawat wrote: > >> Refactor the UFS PHY reset handling to parse the reset logic only once > >> during probe, instead of every resume. > >> > >> Move the UFS PHY reset parsing logic from qmp_phy_power_on to > >> qmp_ufs_probe to avoid unnecessary parsing during resume. > > > > How did you solve the circular dependency issue being noted below? > > Hi Dmitry, > As part of my patch, I moved the parsing logic from qmp_phy_power_on to > qmp_ufs_probe to avoid unnecessary parsing during resume. I'm uncertain > about the circular dependency issue and whether if it still exists. It surely does. The reset controller is registered in the beginning of ufs_qcom_init() and the PHY is acquired only a few lines below. It creates a very small window for PHY driver to probe. Which means, NAK, this patch doesn't look acceptable. > > Regards, > Nitin > > > > > >> > >> Co-developed-by: Ram Kumar Dwivedi <quic_rdwivedi@quicinc.com> > >> Signed-off-by: Ram Kumar Dwivedi <quic_rdwivedi@quicinc.com> > >> Signed-off-by: Nitin Rawat <quic_nitirawa@quicinc.com> > >> --- > >> drivers/phy/qualcomm/phy-qcom-qmp-ufs.c | 61 +++++++++++++------------ > >> 1 file changed, 33 insertions(+), 28 deletions(-) > >> > >> diff --git a/drivers/phy/qualcomm/phy-qcom-qmp-ufs.c b/drivers/phy/qualcomm/phy-qcom-qmp-ufs.c > >> index 636dc3dc3ea8..12dad28cc1bd 100644 > >> --- a/drivers/phy/qualcomm/phy-qcom-qmp-ufs.c > >> +++ b/drivers/phy/qualcomm/phy-qcom-qmp-ufs.c > >> @@ -1799,38 +1799,11 @@ static int qmp_ufs_com_exit(struct qmp_ufs *qmp) > >> static int qmp_ufs_power_on(struct phy *phy) > >> { > >> struct qmp_ufs *qmp = phy_get_drvdata(phy); > >> - const struct qmp_phy_cfg *cfg = qmp->cfg; > >> int ret; > >> dev_vdbg(qmp->dev, "Initializing QMP phy\n"); > >> > >> - if (cfg->no_pcs_sw_reset) { > >> - /* > >> - * Get UFS reset, which is delayed until now to avoid a > >> - * circular dependency where UFS needs its PHY, but the PHY > >> - * needs this UFS reset. > >> - */ > >> - if (!qmp->ufs_reset) { > >> - qmp->ufs_reset = > >> - devm_reset_control_get_exclusive(qmp->dev, > >> - "ufsphy"); > >> - > >> - if (IS_ERR(qmp->ufs_reset)) { > >> - ret = PTR_ERR(qmp->ufs_reset); > >> - dev_err(qmp->dev, > >> - "failed to get UFS reset: %d\n", > >> - ret); > >> - > >> - qmp->ufs_reset = NULL; > >> - return ret; > >> - } > >> - } > >> - } > >> - > >> ret = qmp_ufs_com_init(qmp); > >> - if (ret) > >> - return ret; > >> - > >> - return 0; > >> + return ret; > >> } > >> > >> static int qmp_ufs_phy_calibrate(struct phy *phy) > >> @@ -2088,6 +2061,34 @@ static int qmp_ufs_parse_dt(struct qmp_ufs *qmp) > >> return 0; > >> } > >> > >> +static int qmp_ufs_get_phy_reset(struct qmp_ufs *qmp) > >> +{ > >> + const struct qmp_phy_cfg *cfg = qmp->cfg; > >> + int ret; > >> + > >> + if (!cfg->no_pcs_sw_reset) > >> + return 0; > >> + > >> + /* > >> + * Get UFS reset, which is delayed until now to avoid a > >> + * circular dependency where UFS needs its PHY, but the PHY > >> + * needs this UFS reset. > >> + */ > >> + if (!qmp->ufs_reset) { > >> + qmp->ufs_reset = > >> + devm_reset_control_get_exclusive(qmp->dev, "ufsphy"); > > > > Strange indentation. > > > >> + > >> + if (IS_ERR(qmp->ufs_reset)) { > >> + ret = PTR_ERR(qmp->ufs_reset); > >> + dev_err(qmp->dev, "failed to get PHY reset: %d\n", ret); > >> + qmp->ufs_reset = NULL; > >> + return ret; > >> + } > >> + } > >> + > >> + return 0; > >> +} > >> + > >> static int qmp_ufs_probe(struct platform_device *pdev) > >> { > >> struct device *dev = &pdev->dev; > >> @@ -2114,6 +2115,10 @@ static int qmp_ufs_probe(struct platform_device *pdev) > >> if (ret) > >> return ret; > >> > >> + ret = qmp_ufs_get_phy_reset(qmp); > >> + if (ret) > >> + return ret; > >> + > >> /* Check for legacy binding with child node. */ > >> np = of_get_next_available_child(dev->of_node, NULL); > >> if (np) { > >> -- > >> 2.48.1 > >> > > >
On 14/04/2025 23:34, Nitin Rawat wrote: > > > On 4/11/2025 4:38 PM, Dmitry Baryshkov wrote: >> On Fri, 11 Apr 2025 at 13:50, Nitin Rawat <quic_nitirawa@quicinc.com> >> wrote: >>> >>> >>> >>> On 4/11/2025 1:38 AM, Dmitry Baryshkov wrote: >>>> On Thu, Apr 10, 2025 at 02:30:57PM +0530, Nitin Rawat wrote: >>>>> Refactor the UFS PHY reset handling to parse the reset logic only once >>>>> during probe, instead of every resume. >>>>> >>>>> Move the UFS PHY reset parsing logic from qmp_phy_power_on to >>>>> qmp_ufs_probe to avoid unnecessary parsing during resume. >>>> >>>> How did you solve the circular dependency issue being noted below? >>> >>> Hi Dmitry, >>> As part of my patch, I moved the parsing logic from qmp_phy_power_on to >>> qmp_ufs_probe to avoid unnecessary parsing during resume. I'm uncertain >>> about the circular dependency issue and whether if it still exists. >> >> It surely does. The reset controller is registered in the beginning of >> ufs_qcom_init() and the PHY is acquired only a few lines below. It >> creates a very small window for PHY driver to probe. >> Which means, NAK, this patch doesn't look acceptable. > > Hi Dmitry, > > Thanks for pointing this out. I agree that it leaves very little time > for the PHY to probe, which may cause issues with targets where > no_pcs_sw_reset is set to true. > > As an experiment, I kept no_pcs_sw_reset set to true for the SM8750, and > it caused bootup probe issues in some of the iterations I ran. > > To address this, I propose updating the patch to move the > qmp_ufs_get_phy_reset call to phy_calibrate, just before the > reset_control_assert call. Will it cause an issue if we move it to phy_init() instead of phy_calibrate()? > > This change will delay the UFS PHY reset as much as possible in the > code. Additionally, moving it from phy_power_on to calibrate will ensure > that qmp_ufs_get_phy_reset is called only once during boot, rather than > during each phy_power_on call. > > Please let me know your thoughts. > ===================================================================================================== > static int qmp_ufs_phy_calibrate(struct phy *phy) > { > struct qmp_ufs *qmp = phy_get_drvdata(phy); > @@ -1793,6 +1826,12 @@ static int qmp_ufs_phy_calibrate(struct phy *phy) > unsigned int val; > int ret; > > + pr_err("%s %d\n", __func__, __LINE__); > + > + ret = qmp_ufs_get_phy_reset(qmp); > + if (ret) > + return ret; > + > ret = reset_control_assert(qmp->ufs_reset); > if (ret) > return ret; > @@ -1817,7 +1856,7 @@ static int qmp_ufs_phy_calibrate(struct phy *phy) > dev_err(qmp->dev, "phy initialization timed-out\n"); > return ret; > ===================================================================================================== > > > Regards. > Nitin >> >>> >>> Regards, >>> Nitin >>> >>> >>>> >>>>> >>>>> Co-developed-by: Ram Kumar Dwivedi <quic_rdwivedi@quicinc.com> >>>>> Signed-off-by: Ram Kumar Dwivedi <quic_rdwivedi@quicinc.com> >>>>> Signed-off-by: Nitin Rawat <quic_nitirawa@quicinc.com> >>>>> --- >>>>> drivers/phy/qualcomm/phy-qcom-qmp-ufs.c | 61 ++++++++++++ >>>>> +------------ >>>>> 1 file changed, 33 insertions(+), 28 deletions(-) >>>>> >>>>> diff --git a/drivers/phy/qualcomm/phy-qcom-qmp-ufs.c b/drivers/phy/ >>>>> qualcomm/phy-qcom-qmp-ufs.c >>>>> index 636dc3dc3ea8..12dad28cc1bd 100644 >>>>> --- a/drivers/phy/qualcomm/phy-qcom-qmp-ufs.c >>>>> +++ b/drivers/phy/qualcomm/phy-qcom-qmp-ufs.c >>>>> @@ -1799,38 +1799,11 @@ static int qmp_ufs_com_exit(struct qmp_ufs >>>>> *qmp) >>>>> static int qmp_ufs_power_on(struct phy *phy) >>>>> { >>>>> struct qmp_ufs *qmp = phy_get_drvdata(phy); >>>>> - const struct qmp_phy_cfg *cfg = qmp->cfg; >>>>> int ret; >>>>> dev_vdbg(qmp->dev, "Initializing QMP phy\n"); >>>>> >>>>> - if (cfg->no_pcs_sw_reset) { >>>>> - /* >>>>> - * Get UFS reset, which is delayed until now to avoid a >>>>> - * circular dependency where UFS needs its PHY, but >>>>> the PHY >>>>> - * needs this UFS reset. >>>>> - */ >>>>> - if (!qmp->ufs_reset) { >>>>> - qmp->ufs_reset = >>>>> - devm_reset_control_get_exclusive(qmp- >>>>> >dev, >>>>> - >>>>> "ufsphy"); >>>>> - >>>>> - if (IS_ERR(qmp->ufs_reset)) { >>>>> - ret = PTR_ERR(qmp->ufs_reset); >>>>> - dev_err(qmp->dev, >>>>> - "failed to get UFS reset: %d\n", >>>>> - ret); >>>>> - >>>>> - qmp->ufs_reset = NULL; >>>>> - return ret; >>>>> - } >>>>> - } >>>>> - } >>>>> - >>>>> ret = qmp_ufs_com_init(qmp); >>>>> - if (ret) >>>>> - return ret; >>>>> - >>>>> - return 0; >>>>> + return ret; >>>>> } >>>>> >>>>> static int qmp_ufs_phy_calibrate(struct phy *phy) >>>>> @@ -2088,6 +2061,34 @@ static int qmp_ufs_parse_dt(struct qmp_ufs >>>>> *qmp) >>>>> return 0; >>>>> } >>>>> >>>>> +static int qmp_ufs_get_phy_reset(struct qmp_ufs *qmp) >>>>> +{ >>>>> + const struct qmp_phy_cfg *cfg = qmp->cfg; >>>>> + int ret; >>>>> + >>>>> + if (!cfg->no_pcs_sw_reset) >>>>> + return 0; >>>>> + >>>>> + /* >>>>> + * Get UFS reset, which is delayed until now to avoid a >>>>> + * circular dependency where UFS needs its PHY, but the PHY >>>>> + * needs this UFS reset. >>>>> + */ >>>>> + if (!qmp->ufs_reset) { >>>>> + qmp->ufs_reset = >>>>> + devm_reset_control_get_exclusive(qmp->dev, "ufsphy"); >>>> >>>> Strange indentation. >>>> >>>>> + >>>>> + if (IS_ERR(qmp->ufs_reset)) { >>>>> + ret = PTR_ERR(qmp->ufs_reset); >>>>> + dev_err(qmp->dev, "failed to get PHY reset: >>>>> %d\n", ret); >>>>> + qmp->ufs_reset = NULL; >>>>> + return ret; >>>>> + } >>>>> + } >>>>> + >>>>> + return 0; >>>>> +} >>>>> + >>>>> static int qmp_ufs_probe(struct platform_device *pdev) >>>>> { >>>>> struct device *dev = &pdev->dev; >>>>> @@ -2114,6 +2115,10 @@ static int qmp_ufs_probe(struct >>>>> platform_device *pdev) >>>>> if (ret) >>>>> return ret; >>>>> >>>>> + ret = qmp_ufs_get_phy_reset(qmp); >>>>> + if (ret) >>>>> + return ret; >>>>> + >>>>> /* Check for legacy binding with child node. */ >>>>> np = of_get_next_available_child(dev->of_node, NULL); >>>>> if (np) { >>>>> -- >>>>> 2.48.1 >>>>> >>>> >>> >> >> >