From c098fbf4cf6cba67bde1bdbc5a5035fd19f83742 Mon Sep 17 00:00:00 2001 From: Adrian Hunter Date: Tue, 3 Nov 2020 16:14:02 +0200 Subject: [PATCH] UPSTREAM: scsi: ufs: Add DeepSleep feature DeepSleep is a UFS v3.1 feature that achieves the lowest power consumption of the device, apart from power off. In DeepSleep mode, no commands are accepted, and the only way to exit is using a hardware reset or power cycle. This patch assumes that if a power cycle was an option, then power off would be preferable, so only exit via a hardware reset is supported. Drivers that wish to support DeepSleep need to set a new capability flag UFSHCD_CAP_DEEPSLEEP and provide a hardware reset via the existing ->device_reset() callback. It is assumed that UFS devices with wspecversion >= 0x310 support DeepSleep. [mkp: dropped sysfs ABI doc due to conflicts] Link: https://lore.kernel.org/r/20201103141403.2142-2-adrian.hunter@intel.com Reviewed-by: Bean Huo Reviewed-by: Asutosh Das Reviewed-by: Stanley Chu Reviewed-by: Can Guo Acked-by: Jonathan Corbet Acked-by: Suzuki K Poulose Signed-off-by: Adrian Hunter Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Greg Kroah-Hartman Signed-off-by: Martin K. Petersen (cherry picked from commit fe1d4c2ebcae994dffe8673cc3cba10102d15d11) Bug: 204438323 Change-Id: I054995d84b1d92b696ab9d8dda0946c1bbe47f92 Signed-off-by: Bart Van Assche --- drivers/scsi/ufs/ufs-sysfs.c | 7 +++++++ drivers/scsi/ufs/ufs.h | 1 + drivers/scsi/ufs/ufshcd.c | 38 ++++++++++++++++++++++++++++++++++-- drivers/scsi/ufs/ufshcd.h | 17 +++++++++++++++- include/trace/events/ufs.h | 3 ++- 5 files changed, 62 insertions(+), 4 deletions(-) diff --git a/drivers/scsi/ufs/ufs-sysfs.c b/drivers/scsi/ufs/ufs-sysfs.c index 4c02591058c6..fa5e0ddcbd7b 100644 --- a/drivers/scsi/ufs/ufs-sysfs.c +++ b/drivers/scsi/ufs/ufs-sysfs.c @@ -30,6 +30,7 @@ static const char *ufschd_ufs_dev_pwr_mode_to_string( case UFS_ACTIVE_PWR_MODE: return "ACTIVE"; case UFS_SLEEP_PWR_MODE: return "SLEEP"; case UFS_POWERDOWN_PWR_MODE: return "POWERDOWN"; + case UFS_DEEPSLEEP_PWR_MODE: return "DEEPSLEEP"; default: return "UNKNOWN"; } } @@ -40,6 +41,7 @@ static inline ssize_t ufs_sysfs_pm_lvl_store(struct device *dev, bool rpm) { struct ufs_hba *hba = dev_get_drvdata(dev); + struct ufs_dev_info *dev_info = &hba->dev_info; unsigned long flags, value; if (kstrtoul(buf, 0, &value)) @@ -48,6 +50,11 @@ static inline ssize_t ufs_sysfs_pm_lvl_store(struct device *dev, if (value >= UFS_PM_LVL_MAX) return -EINVAL; + if (ufs_pm_lvl_states[value].dev_state == UFS_DEEPSLEEP_PWR_MODE && + (!(hba->caps & UFSHCD_CAP_DEEPSLEEP) || + !(dev_info->wspecversion >= 0x310))) + return -EINVAL; + spin_lock_irqsave(hba->host->host_lock, flags); if (rpm) hba->rpm_lvl = value; diff --git a/drivers/scsi/ufs/ufs.h b/drivers/scsi/ufs/ufs.h index 1ee80cda3d01..6f4943e1d43e 100644 --- a/drivers/scsi/ufs/ufs.h +++ b/drivers/scsi/ufs/ufs.h @@ -456,6 +456,7 @@ enum ufs_dev_pwr_mode { UFS_ACTIVE_PWR_MODE = 1, UFS_SLEEP_PWR_MODE = 2, UFS_POWERDOWN_PWR_MODE = 3, + UFS_DEEPSLEEP_PWR_MODE = 4, }; #define UFS_WB_BUF_REMAIN_PERCENT(val) ((val) / 10) diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c index a9e62474b1fa..4123459a9981 100644 --- a/drivers/scsi/ufs/ufshcd.c +++ b/drivers/scsi/ufs/ufshcd.c @@ -168,6 +168,11 @@ struct ufs_pm_lvl_states ufs_pm_lvl_states[] = { {UFS_SLEEP_PWR_MODE, UIC_LINK_HIBERN8_STATE}, {UFS_POWERDOWN_PWR_MODE, UIC_LINK_HIBERN8_STATE}, {UFS_POWERDOWN_PWR_MODE, UIC_LINK_OFF_STATE}, + /* + * For DeepSleep, the link is first put in hibern8 and then off. + * Leaving the link in hibern8 is not supported. + */ + {UFS_DEEPSLEEP_PWR_MODE, UIC_LINK_OFF_STATE}, }; static inline enum ufs_dev_pwr_mode @@ -8544,7 +8549,8 @@ static int ufshcd_link_state_transition(struct ufs_hba *hba, } /* * If autobkops is enabled, link can't be turned off because - * turning off the link would also turn off the device. + * turning off the link would also turn off the device, except in the + * case of DeepSleep where the device is expected to remain powered. */ else if ((req_link_state == UIC_LINK_OFF_STATE) && (!check_for_bkops || !hba->auto_bkops_enabled)) { @@ -8554,6 +8560,9 @@ static int ufshcd_link_state_transition(struct ufs_hba *hba, * put the link in low power mode is to send the DME end point * to device and then send the DME reset command to local * unipro. But putting the link in hibern8 is much faster. + * + * Note also that putting the link in Hibern8 is a requirement + * for entering DeepSleep. */ ret = ufshcd_uic_hibern8_enter(hba); if (ret) { @@ -8686,6 +8695,7 @@ static void ufshcd_hba_vreg_set_hpm(struct ufs_hba *hba) static int ufshcd_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op) { int ret = 0; + int check_for_bkops; enum ufs_pm_level pm_lvl; enum ufs_dev_pwr_mode req_dev_pwr_mode; enum uic_link_state req_link_state; @@ -8771,7 +8781,12 @@ static int ufshcd_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op) } } - ret = ufshcd_link_state_transition(hba, req_link_state, 1); + /* + * In the case of DeepSleep, the device is expected to remain powered + * with the link off, so do not check for bkops. + */ + check_for_bkops = !ufshcd_is_ufs_dev_deepsleep(hba); + ret = ufshcd_link_state_transition(hba, req_link_state, check_for_bkops); if (ret) goto set_dev_active; @@ -8806,11 +8821,25 @@ disable_clks: set_link_active: ufshcd_vreg_set_hpm(hba); + /* + * Device hardware reset is required to exit DeepSleep. Also, for + * DeepSleep, the link is off so host reset and restore will be done + * further below. + */ + if (ufshcd_is_ufs_dev_deepsleep(hba)) { + ufshcd_vops_device_reset(hba); + WARN_ON(!ufshcd_is_link_off(hba)); + } if (ufshcd_is_link_hibern8(hba) && !ufshcd_uic_hibern8_exit(hba)) ufshcd_set_link_active(hba); else if (ufshcd_is_link_off(hba)) ufshcd_host_reset_and_restore(hba); set_dev_active: + /* Can also get here needing to exit DeepSleep */ + if (ufshcd_is_ufs_dev_deepsleep(hba)) { + ufshcd_vops_device_reset(hba); + ufshcd_host_reset_and_restore(hba); + } if (!ufshcd_set_dev_pwr_mode(hba, UFS_ACTIVE_PWR_MODE)) ufshcd_disable_auto_bkops(hba); enable_gating: @@ -8874,6 +8903,9 @@ static int ufshcd_resume(struct ufs_hba *hba, enum ufs_pm_op pm_op) if (ret) goto disable_irq_and_vops_clks; + /* For DeepSleep, the only supported option is to have the link off */ + WARN_ON(ufshcd_is_ufs_dev_deepsleep(hba) && !ufshcd_is_link_off(hba)); + if (ufshcd_is_link_hibern8(hba)) { ret = ufshcd_uic_hibern8_exit(hba); if (!ret) { @@ -8887,6 +8919,8 @@ static int ufshcd_resume(struct ufs_hba *hba, enum ufs_pm_op pm_op) /* * A full initialization of the host and the device is * required since the link was put to off during suspend. + * Note, in the case of DeepSleep, the device will exit + * DeepSleep due to device reset. */ ret = ufshcd_reset_and_restore(hba); /* diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h index a3469c981f97..7270de2f9a74 100644 --- a/drivers/scsi/ufs/ufshcd.h +++ b/drivers/scsi/ufs/ufshcd.h @@ -140,16 +140,22 @@ enum uic_link_state { ((h)->curr_dev_pwr_mode = UFS_SLEEP_PWR_MODE) #define ufshcd_set_ufs_dev_poweroff(h) \ ((h)->curr_dev_pwr_mode = UFS_POWERDOWN_PWR_MODE) +#define ufshcd_set_ufs_dev_deepsleep(h) \ + ((h)->curr_dev_pwr_mode = UFS_DEEPSLEEP_PWR_MODE) #define ufshcd_is_ufs_dev_active(h) \ ((h)->curr_dev_pwr_mode == UFS_ACTIVE_PWR_MODE) #define ufshcd_is_ufs_dev_sleep(h) \ ((h)->curr_dev_pwr_mode == UFS_SLEEP_PWR_MODE) #define ufshcd_is_ufs_dev_poweroff(h) \ ((h)->curr_dev_pwr_mode == UFS_POWERDOWN_PWR_MODE) +#define ufshcd_is_ufs_dev_deepsleep(h) \ + ((h)->curr_dev_pwr_mode == UFS_DEEPSLEEP_PWR_MODE) /* * UFS Power management levels. - * Each level is in increasing order of power savings. + * Each level is in increasing order of power savings, except DeepSleep + * which is lower than PowerDown with power on but not PowerDown with + * power off. */ enum ufs_pm_level { UFS_PM_LVL_0, /* UFS_ACTIVE_PWR_MODE, UIC_LINK_ACTIVE_STATE */ @@ -158,6 +164,7 @@ enum ufs_pm_level { UFS_PM_LVL_3, /* UFS_SLEEP_PWR_MODE, UIC_LINK_HIBERN8_STATE */ UFS_PM_LVL_4, /* UFS_POWERDOWN_PWR_MODE, UIC_LINK_HIBERN8_STATE */ UFS_PM_LVL_5, /* UFS_POWERDOWN_PWR_MODE, UIC_LINK_OFF_STATE */ + UFS_PM_LVL_6, /* UFS_DEEPSLEEP_PWR_MODE, UIC_LINK_OFF_STATE */ UFS_PM_LVL_MAX }; @@ -668,6 +675,14 @@ enum ufshcd_caps { * This would increase power savings. */ UFSHCD_CAP_AGGR_POWER_COLLAPSE = 1 << 9, + + /* + * This capability allows the host controller driver to use DeepSleep, + * if it is supported by the UFS device. The host controller driver must + * support device hardware reset via the hba->device_reset() callback, + * in order to exit DeepSleep state. + */ + UFSHCD_CAP_DEEPSLEEP = 1 << 10, }; struct ufs_hba_variant_params { diff --git a/include/trace/events/ufs.h b/include/trace/events/ufs.h index 50654f352639..0bd54a184391 100644 --- a/include/trace/events/ufs.h +++ b/include/trace/events/ufs.h @@ -28,7 +28,8 @@ #define UFS_PWR_MODES \ EM(UFS_ACTIVE_PWR_MODE) \ EM(UFS_SLEEP_PWR_MODE) \ - EMe(UFS_POWERDOWN_PWR_MODE) + EM(UFS_POWERDOWN_PWR_MODE) \ + EMe(UFS_DEEPSLEEP_PWR_MODE) #define UFSCHD_CLK_GATING_STATES \ EM(CLKS_OFF) \