| Message ID | 1590074615-10787-1-git-send-email-vbadigan@codeaurora.org |
|---|---|
| Headers | show |
| Series | Internal voltage control for qcom SDHC | expand |
Hi Bjorn, On 5/22/2020 12:37 AM, Bjorn Andersson wrote: > On Thu 21 May 08:23 PDT 2020, Veerabhadrarao Badiganti wrote: > >> On qcom SD host controllers voltage switching be done after the HW >> is ready for it. The HW informs its readiness through power irq. >> The voltage switching should happen only then. >> >> Use the internal voltage switching and then control the voltage >> switching using power irq. >> >> Set the regulator load as well so that regulator can be configured >> in LPM mode when in is not being used. >> >> Co-developed-by: Asutosh Das <asutoshd@codeaurora.org> >> Signed-off-by: Asutosh Das <asutoshd@codeaurora.org> >> Co-developed-by: Vijay Viswanath <vviswana@codeaurora.org> >> Signed-off-by: Vijay Viswanath <vviswana@codeaurora.org> >> Co-developed-by: Veerabhadrarao Badiganti <vbadigan@codeaurora.org> >> Signed-off-by: Veerabhadrarao Badiganti <vbadigan@codeaurora.org> > Looks better, thanks. > >> --- >> drivers/mmc/host/sdhci-msm.c | 207 +++++++++++++++++++++++++++++++++++++++++-- >> 1 file changed, 198 insertions(+), 9 deletions(-) >> >> diff --git a/drivers/mmc/host/sdhci-msm.c b/drivers/mmc/host/sdhci-msm.c > [..] >> static const struct sdhci_msm_offset *sdhci_priv_msm_offset(struct sdhci_host *host) >> @@ -1298,6 +1302,71 @@ static void sdhci_msm_set_uhs_signaling(struct sdhci_host *host, >> sdhci_msm_hs400(host, &mmc->ios); >> } >> >> +static int sdhci_msm_set_vmmc(struct mmc_host *mmc) >> +{ >> + int ret; >> + >> + if (IS_ERR(mmc->supply.vmmc)) >> + return 0; >> + >> + ret = mmc_regulator_set_ocr(mmc, mmc->supply.vmmc, mmc->ios.vdd); >> + if (ret) >> + dev_err(mmc_dev(mmc), "%s: vmmc set ocr with vdd=%d failed: %d\n", >> + mmc_hostname(mmc), mmc->ios.vdd, ret); > Missed this one on v1, in the event that mmc_regulator_set_ocr() return > a non-zero value it has already printed an error message. So please > replace the tail with just: > > return mmc_regulator_set_ocr(...); > >> + >> + return ret; >> +} >> + >> +static int sdhci_msm_set_vqmmc(struct sdhci_msm_host *msm_host, >> + struct mmc_host *mmc, bool level) >> +{ >> + int load, ret; >> + struct mmc_ios ios; >> + >> + if (IS_ERR(mmc->supply.vqmmc) || >> + (mmc->ios.power_mode == MMC_POWER_UNDEFINED) || >> + (msm_host->vqmmc_enabled == level)) >> + return 0; >> + >> + if (msm_host->vqmmc_load) { >> + load = level ? msm_host->vqmmc_load : 0; >> + ret = regulator_set_load(mmc->supply.vqmmc, load); > Sorry for the late reply on v1, but please see my explanation regarding > load and always-on regulators there. <Merging your comment from V1 here> >> You should still call regulator_enable()/regulator_disable() on your >> consumer regulator in this driver. When you do this the regulator core >> will conclude that the regulator_dev (i.e. the part that represents the >> hardware) is marked always_on and will not enable/disable the regulator. >> But it will still invoke _regulator_handle_consumer_enable() and >> _regulator_handle_consumer_disable(), which will aggregate the "load" of >> all client regulators and update the regulator's load. >> So this will apply the load as you expect regardless of it being >> supplied by a regulator marked as always_on. Since I'm not turning off this regulator for eMMC, I wanted to keep it in LPM mode to save some power. When the regulator configured in auto mode (RPMH_REGULATOR_MODE_AUTO) it switches to LPM/HPM mode based on the active load. So i have to minimize my driver load requirement so that I can let this regulator in LPM mode. So i need to set load every-time I disable/enable the regulator. >> + if (ret) { >> + dev_err(mmc_dev(mmc), "%s: vqmmc set load failed: %d\n", >> + mmc_hostname(mmc), ret); >> + goto out; >> + } >> + } >> + >> + if (level) { >> + /* Set the IO voltage regulator to default voltage level */ >> + if (msm_host->caps_0 & CORE_3_0V_SUPPORT) >> + ios.signal_voltage = MMC_SIGNAL_VOLTAGE_330; >> + else if (msm_host->caps_0 & CORE_1_8V_SUPPORT) >> + ios.signal_voltage = MMC_SIGNAL_VOLTAGE_180; >> + >> + if (msm_host->caps_0 & CORE_VOLT_SUPPORT) { >> + ret = mmc_regulator_set_vqmmc(mmc, &ios); >> + if (ret < 0) { >> + dev_err(mmc_dev(mmc), "%s: vqmmc set volgate failed: %d\n", >> + mmc_hostname(mmc), ret); >> + goto out; >> + } >> + } >> + ret = regulator_enable(mmc->supply.vqmmc); >> + } else { >> + ret = regulator_disable(mmc->supply.vqmmc); >> + } >> + >> + if (ret) >> + dev_err(mmc_dev(mmc), "%s: vqmm %sable failed: %d\n", >> + mmc_hostname(mmc), level ? "en":"dis", ret); >> + else >> + msm_host->vqmmc_enabled = level; >> +out: >> + return ret; >> +} > [..] >> +static int sdhci_msm_start_signal_voltage_switch(struct mmc_host *mmc, >> + struct mmc_ios *ios) >> +{ >> + struct sdhci_host *host = mmc_priv(mmc); >> + u16 ctrl, status; >> + >> + /* >> + * Signal Voltage Switching is only applicable for Host Controllers >> + * v3.00 and above. >> + */ >> + if (host->version < SDHCI_SPEC_300) >> + return 0; >> + >> + ctrl = sdhci_readw(host, SDHCI_HOST_CONTROL2); >> + >> + switch (ios->signal_voltage) { >> + case MMC_SIGNAL_VOLTAGE_330: >> + if (!(host->flags & SDHCI_SIGNALING_330)) >> + return -EINVAL; >> + >> + /* Set 1.8V Signal Enable in the Host Control2 register to 0 */ >> + ctrl &= ~SDHCI_CTRL_VDD_180; >> + break; >> + case MMC_SIGNAL_VOLTAGE_180: >> + if (!(host->flags & SDHCI_SIGNALING_180)) >> + return -EINVAL; >> + >> + /* >> + * Enable 1.8V Signal Enable in the Host Control2 >> + * register >> + */ >> + ctrl |= SDHCI_CTRL_VDD_180; >> + break; >> + case MMC_SIGNAL_VOLTAGE_120: >> + if (!(host->flags & SDHCI_SIGNALING_120)) >> + return -EINVAL; >> + return 0; >> + default: >> + /* No signal voltage switch required */ >> + return 0; >> + } >> + >> + sdhci_writew(host, ctrl, SDHCI_HOST_CONTROL2); >> + >> + /* Wait for 5ms */ >> + usleep_range(5000, 5500); >> + >> + /* regulator output should be stable within 5 ms */ >> + status = !!(ctrl & SDHCI_CTRL_VDD_180); >> + ctrl = sdhci_readw(host, SDHCI_HOST_CONTROL2); >> + if (!!(ctrl & SDHCI_CTRL_VDD_180) == status) > You should be able to drop the !! both here and when assigning status. > > Overall this looks neater, thanks for reworking it. > > Regards, > Bjorn Thanks Veera
On 5/22/2020 10:34 PM, Bjorn Andersson wrote: > On Fri 22 May 06:27 PDT 2020, Veerabhadrarao Badiganti wrote: > >> Hi Bjorn, >> >> On 5/22/2020 12:37 AM, Bjorn Andersson wrote: >>> On Thu 21 May 08:23 PDT 2020, Veerabhadrarao Badiganti wrote: >>> >>>> On qcom SD host controllers voltage switching be done after the HW >>>> is ready for it. The HW informs its readiness through power irq. >>>> The voltage switching should happen only then. >>>> >>>> Use the internal voltage switching and then control the voltage >>>> switching using power irq. >>>> >>>> Set the regulator load as well so that regulator can be configured >>>> in LPM mode when in is not being used. >>>> >>>> Co-developed-by: Asutosh Das <asutoshd@codeaurora.org> >>>> Signed-off-by: Asutosh Das <asutoshd@codeaurora.org> >>>> Co-developed-by: Vijay Viswanath <vviswana@codeaurora.org> >>>> Signed-off-by: Vijay Viswanath <vviswana@codeaurora.org> >>>> Co-developed-by: Veerabhadrarao Badiganti <vbadigan@codeaurora.org> >>>> Signed-off-by: Veerabhadrarao Badiganti <vbadigan@codeaurora.org> >>> Looks better, thanks. >>> >>>> --- >>>> drivers/mmc/host/sdhci-msm.c | 207 +++++++++++++++++++++++++++++++++++++++++-- >>>> 1 file changed, 198 insertions(+), 9 deletions(-) >>>> >>>> diff --git a/drivers/mmc/host/sdhci-msm.c b/drivers/mmc/host/sdhci-msm.c >>> [..] >>>> static const struct sdhci_msm_offset *sdhci_priv_msm_offset(struct sdhci_host *host) >>>> @@ -1298,6 +1302,71 @@ static void sdhci_msm_set_uhs_signaling(struct sdhci_host *host, >>>> sdhci_msm_hs400(host, &mmc->ios); >>>> } >>>> +static int sdhci_msm_set_vmmc(struct mmc_host *mmc) >>>> +{ >>>> + int ret; >>>> + >>>> + if (IS_ERR(mmc->supply.vmmc)) >>>> + return 0; >>>> + >>>> + ret = mmc_regulator_set_ocr(mmc, mmc->supply.vmmc, mmc->ios.vdd); >>>> + if (ret) >>>> + dev_err(mmc_dev(mmc), "%s: vmmc set ocr with vdd=%d failed: %d\n", >>>> + mmc_hostname(mmc), mmc->ios.vdd, ret); >>> Missed this one on v1, in the event that mmc_regulator_set_ocr() return >>> a non-zero value it has already printed an error message. So please >>> replace the tail with just: >>> >>> return mmc_regulator_set_ocr(...); >>> >>>> + >>>> + return ret; >>>> +} >>>> + >>>> +static int sdhci_msm_set_vqmmc(struct sdhci_msm_host *msm_host, >>>> + struct mmc_host *mmc, bool level) >>>> +{ >>>> + int load, ret; >>>> + struct mmc_ios ios; >>>> + >>>> + if (IS_ERR(mmc->supply.vqmmc) || >>>> + (mmc->ios.power_mode == MMC_POWER_UNDEFINED) || >>>> + (msm_host->vqmmc_enabled == level)) >>>> + return 0; >>>> + >>>> + if (msm_host->vqmmc_load) { >>>> + load = level ? msm_host->vqmmc_load : 0; >>>> + ret = regulator_set_load(mmc->supply.vqmmc, load); >>> Sorry for the late reply on v1, but please see my explanation regarding >>> load and always-on regulators there. >> <Merging your comment from V1 here> >> >>>> You should still call regulator_enable()/regulator_disable() on your >>>> consumer regulator in this driver. When you do this the regulator core >>>> will conclude that the regulator_dev (i.e. the part that represents the >>>> hardware) is marked always_on and will not enable/disable the regulator. >>>> But it will still invoke _regulator_handle_consumer_enable() and >>>> _regulator_handle_consumer_disable(), which will aggregate the "load" of >>>> all client regulators and update the regulator's load. >>>> So this will apply the load as you expect regardless of it being >>>> supplied by a regulator marked as always_on. >> Since I'm not turning off this regulator for eMMC, I wanted to keep it in >> LPM mode >> to save some power. >> When the regulator configured in auto mode (RPMH_REGULATOR_MODE_AUTO) it >> switches to LPM/HPM mode based on the active load. >> So i have to minimize my driver load requirement so that I can let this >> regulator >> in LPM mode. >> So i need to set load every-time I disable/enable the regulator. >> > You call regulator_enable(vqmmc) and regulator_disable() below, so you > are telling the regulator framework that your struct regulator should be > "on" or "off". > > This will cause the sum of all struct regulator's for the underlying > struct regulator_dev to be recalculated. So after calling > regulator_disable() below your effective addition to the load > calculation is 0, regardless of which load you have specified. > > Independent of this the property regulator-always-on (always_on in > struct regulator_dev) will determine if the enable/disable request will > actually be sent to the RPMh. > > > So, if you where to not call regulator_disable() for eMMC your argument > is correct, but as far as I can see you are and you're relying on the > regulator core to keep it always-on - and then the load logic is in > effect still. Thanks for the details Bjorn. My requirement is, for eMMC i shouldn't be turning this regulator off. But has to configure in LPM mode. For SD-card, i have to turn-off this regulator. So I'm planning to update the logic as below, let me know if you have any other suggestions. +static int sdhci_msm_set_vqmmc(struct sdhci_msm_host *msm_host, + struct mmc_host *mmc, bool level) +{ + int ret; + bool always_on; + + if (IS_ERR(mmc->supply.vqmmc) || + (mmc->ios.power_mode == MMC_POWER_UNDEFINED)) + return 0; + /* + * For eMMC don't turn off Vqmmc, Instead just configure it in LPM + * and HPM modes by setting the right amount of load. + */ + always_on = mmc->card && mmc_card_mmc(mmc->card); + + if (always_on) + ret = msm_config_vqmmc_mode(msm_host, mmc, level); + else + ret = msm_toggle_vqmmc(msm_host, mmc, level); + + return ret; +} > Regards, > Bjorn > >>>> + if (ret) { >>>> + dev_err(mmc_dev(mmc), "%s: vqmmc set load failed: %d\n", >>>> + mmc_hostname(mmc), ret); >>>> + goto out; >>>> + } >>>> + } >>>> + >>>> + if (level) { >>>> + /* Set the IO voltage regulator to default voltage level */ >>>> + if (msm_host->caps_0 & CORE_3_0V_SUPPORT) >>>> + ios.signal_voltage = MMC_SIGNAL_VOLTAGE_330; >>>> + else if (msm_host->caps_0 & CORE_1_8V_SUPPORT) >>>> + ios.signal_voltage = MMC_SIGNAL_VOLTAGE_180; >>>> + >>>> + if (msm_host->caps_0 & CORE_VOLT_SUPPORT) { >>>> + ret = mmc_regulator_set_vqmmc(mmc, &ios); >>>> + if (ret < 0) { >>>> + dev_err(mmc_dev(mmc), "%s: vqmmc set volgate failed: %d\n", >>>> + mmc_hostname(mmc), ret); >>>> + goto out; >>>> + } >>>> + } >>>> + ret = regulator_enable(mmc->supply.vqmmc); >>>> + } else { >>>> + ret = regulator_disable(mmc->supply.vqmmc); >>>> + } >>>> + >>>> + if (ret) >>>> + dev_err(mmc_dev(mmc), "%s: vqmm %sable failed: %d\n", >>>> + mmc_hostname(mmc), level ? "en":"dis", ret); >>>> + else >>>> + msm_host->vqmmc_enabled = level; >>>> +out: >>>> + return ret; >>>> +}