Messages in this thread | | | Date | Thu, 25 Mar 2021 03:25:19 +0530 | From | nitirawa@codeauro ... | Subject | Re: [PATCH V2 3/3] scsi: ufs-qcom: configure VCC voltage level in vendor file |
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On 2021-03-23 20:58, Bjorn Andersson wrote: > On Sun 21 Mar 16:57 CDT 2021, Nitin Rawat wrote: > >> As a part of vops handler, VCC voltage is updated >> as per the ufs device probed after reading the device >> descriptor. We follow below steps to configure voltage >> level. >> >> 1. Set the device to SLEEP state. >> 2. Disable the Vcc Regulator. >> 3. Set the vcc voltage according to the device type and reenable >> the regulator. >> 4. Set the device mode back to ACTIVE. >> > > When we discussed this a while back this was described as a requirement > from the device specification, you only operate on objects "owned" by > ufshcd and you invoke ufshcd operations to perform the actions. > > So why is this a ufs-qcom patch and not something in ufshcd? > > Regards, > Bjorn > >> Signed-off-by: Nitin Rawat <nitirawa@codeaurora.org> >> Signed-off-by: Veerabhadrarao Badiganti <vbadigan@codeaurora.org> >> --- >> drivers/scsi/ufs/ufs-qcom.c | 51 >> +++++++++++++++++++++++++++++++++++++++++++++ >> 1 file changed, 51 insertions(+) >> >> diff --git a/drivers/scsi/ufs/ufs-qcom.c b/drivers/scsi/ufs/ufs-qcom.c >> index f97d7b0..ca35f5c 100644 >> --- a/drivers/scsi/ufs/ufs-qcom.c >> +++ b/drivers/scsi/ufs/ufs-qcom.c >> @@ -21,6 +21,17 @@ >> #define UFS_QCOM_DEFAULT_DBG_PRINT_EN \ >> (UFS_QCOM_DBG_PRINT_REGS_EN | UFS_QCOM_DBG_PRINT_TEST_BUS_EN) >> >> +#define ANDROID_BOOT_DEV_MAX 30 >> +static char android_boot_dev[ANDROID_BOOT_DEV_MAX]; >> + >> +/* Min and Max VCC voltage values for ufs 2.x and >> + * ufs 3.x devices >> + */ >> +#define UFS_3X_VREG_VCC_MIN_UV 2540000 /* uV */ >> +#define UFS_3X_VREG_VCC_MAX_UV 2700000 /* uV */ >> +#define UFS_2X_VREG_VCC_MIN_UV 2950000 /* uV */ >> +#define UFS_2X_VREG_VCC_MAX_UV 2960000 /* uV */ >> + >> enum { >> TSTBUS_UAWM, >> TSTBUS_UARM, >> @@ -1293,6 +1304,45 @@ static void >> ufs_qcom_print_hw_debug_reg_all(struct ufs_hba *hba, >> print_fn(hba, reg, 9, "UFS_DBG_RD_REG_TMRLUT ", priv); >> } >> >> + /** >> + * ufs_qcom_setup_vcc_regulators - Update VCC voltage >> + * @hba: host controller instance >> + * Update VCC voltage based on UFS device(ufs 2.x or >> + * ufs 3.x probed) >> + */ >> +static int ufs_qcom_setup_vcc_regulators(struct ufs_hba *hba) >> +{ >> + struct ufs_dev_info *dev_info = &hba->dev_info; >> + struct ufs_vreg *vreg = hba->vreg_info.vcc; >> + int ret; >> + >> + /* Put the device in sleep before lowering VCC level */ >> + ret = ufshcd_set_dev_pwr_mode(hba, UFS_SLEEP_PWR_MODE); >> + >> + /* Switch off VCC before switching it ON at 2.5v or 2.96v */ >> + ret = ufshcd_disable_vreg(hba->dev, vreg); >> + >> + /* add ~2ms delay before renabling VCC at lower voltage */ >> + usleep_range(2000, 2100); >> + >> + /* set VCC min and max voltage according to ufs device type */ >> + if (dev_info->wspecversion >= 0x300) { >> + vreg->min_uV = UFS_3X_VREG_VCC_MIN_UV; >> + vreg->max_uV = UFS_3X_VREG_VCC_MAX_UV; >> + } >> + >> + else { >> + vreg->min_uV = UFS_2X_VREG_VCC_MIN_UV; >> + vreg->max_uV = UFS_2X_VREG_VCC_MAX_UV; >> + } >> + >> + ret = ufshcd_enable_vreg(hba->dev, vreg); >> + >> + /* Bring the device in active now */ >> + ret = ufshcd_set_dev_pwr_mode(hba, UFS_ACTIVE_PWR_MODE); >> + return ret; >> +} >> + >> static void ufs_qcom_enable_test_bus(struct ufs_qcom_host *host) >> { >> if (host->dbg_print_en & UFS_QCOM_DBG_PRINT_TEST_BUS_EN) { >> @@ -1490,6 +1540,7 @@ static const struct ufs_hba_variant_ops >> ufs_hba_qcom_vops = { >> .device_reset = ufs_qcom_device_reset, >> .config_scaling_param = ufs_qcom_config_scaling_param, >> .program_key = ufs_qcom_ice_program_key, >> + .setup_vcc_regulators = ufs_qcom_setup_vcc_regulators, >> }; >> >> /** >> -- >> 2.7.4 >>
Hi Bjorn, Thanks for your review. But As per the earlier discussion regarding handling of vcc voltage for platform supporting both ufs 2.x and ufs 3.x , it was finally concluded to use "vops and let vendors handle it, until specs or someone has a better suggestion". Please correct me in case i am wrong.
https://www.mail-archive.com/linux-kernel@vger.kernel.org/msg2399116.html
Regards, Nitin
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