As per specs, e.g, JESD220E chapter 7.2, while powering
off/on the ufs device, RST_N signal and REF_CLK signal
should be between VSS(Ground) and VCCQ/VCCQ2.
To flexibly control device reset line, re-name the function
ufschd_vops_device_reset(sturct ufs_hba *hba) to ufshcd_
vops_toggle_device_reset(sturct ufs_hba *hba, bool down). The
new parameter "bool down" is used to separate device reset
line pulling down from pulling up.
Cc: Kiwoong Kim <[email protected]>
Cc: Stanley Chu <[email protected]>
Signed-off-by: Ziqi Chen <[email protected]>
---
drivers/scsi/ufs/ufs-mediatek.c | 27 +++++++++-----------------
drivers/scsi/ufs/ufs-qcom.c | 22 ++++++++++-----------
drivers/scsi/ufs/ufshcd.c | 43 ++++++++++++++++++++++++++++++-----------
drivers/scsi/ufs/ufshcd.h | 10 +++++-----
4 files changed, 56 insertions(+), 46 deletions(-)
diff --git a/drivers/scsi/ufs/ufs-mediatek.c b/drivers/scsi/ufs/ufs-mediatek.c
index 80618af..bff2c42 100644
--- a/drivers/scsi/ufs/ufs-mediatek.c
+++ b/drivers/scsi/ufs/ufs-mediatek.c
@@ -841,27 +841,18 @@ static int ufs_mtk_link_startup_notify(struct ufs_hba *hba,
return ret;
}
-static int ufs_mtk_device_reset(struct ufs_hba *hba)
+static int ufs_mtk_toggle_device_reset(struct ufs_hba *hba, bool down)
{
struct arm_smccc_res res;
- ufs_mtk_device_reset_ctrl(0, res);
-
- /*
- * The reset signal is active low. UFS devices shall detect
- * more than or equal to 1us of positive or negative RST_n
- * pulse width.
- *
- * To be on safe side, keep the reset low for at least 10us.
- */
- usleep_range(10, 15);
-
- ufs_mtk_device_reset_ctrl(1, res);
-
- /* Some devices may need time to respond to rst_n */
- usleep_range(10000, 15000);
+ if (down) {
+ ufs_mtk_device_reset_ctrl(0, res);
+ } else {
+ ufs_mtk_device_reset_ctrl(1, res);
- dev_info(hba->dev, "device reset done\n");
+ /* Some devices may need time to respond to rst_n */
+ usleep_range(10000, 15000);
+ }
return 0;
}
@@ -1052,7 +1043,7 @@ static const struct ufs_hba_variant_ops ufs_hba_mtk_vops = {
.suspend = ufs_mtk_suspend,
.resume = ufs_mtk_resume,
.dbg_register_dump = ufs_mtk_dbg_register_dump,
- .device_reset = ufs_mtk_device_reset,
+ .toggle_device_reset = ufs_mtk_toggle_device_reset,
.event_notify = ufs_mtk_event_notify,
};
diff --git a/drivers/scsi/ufs/ufs-qcom.c b/drivers/scsi/ufs/ufs-qcom.c
index 2206b1e..c2ccaa5 100644
--- a/drivers/scsi/ufs/ufs-qcom.c
+++ b/drivers/scsi/ufs/ufs-qcom.c
@@ -1404,12 +1404,13 @@ static void ufs_qcom_dump_dbg_regs(struct ufs_hba *hba)
}
/**
- * ufs_qcom_device_reset() - toggle the (optional) device reset line
+ * ufs_qcom_toggle_device_reset() - toggle the (optional) device reset line
* @hba: per-adapter instance
+ * @down: pull down or pull up device reset line
*
* Toggles the (optional) reset line to reset the attached device.
*/
-static int ufs_qcom_device_reset(struct ufs_hba *hba)
+static int ufs_qcom_toggle_device_reset(struct ufs_hba *hba, bool down)
{
struct ufs_qcom_host *host = ufshcd_get_variant(hba);
@@ -1417,15 +1418,12 @@ static int ufs_qcom_device_reset(struct ufs_hba *hba)
if (!host->device_reset)
return -EOPNOTSUPP;
- /*
- * The UFS device shall detect reset pulses of 1us, sleep for 10us to
- * be on the safe side.
- */
- gpiod_set_value_cansleep(host->device_reset, 1);
- usleep_range(10, 15);
-
- gpiod_set_value_cansleep(host->device_reset, 0);
- usleep_range(10, 15);
+ if (down) {
+ gpiod_set_value_cansleep(host->device_reset, 1);
+ } else {
+ gpiod_set_value_cansleep(host->device_reset, 0);
+ usleep_range(10, 15);
+ }
return 0;
}
@@ -1473,7 +1471,7 @@ static const struct ufs_hba_variant_ops ufs_hba_qcom_vops = {
.suspend = ufs_qcom_suspend,
.resume = ufs_qcom_resume,
.dbg_register_dump = ufs_qcom_dump_dbg_regs,
- .device_reset = ufs_qcom_device_reset,
+ .toggle_device_reset = ufs_qcom_toggle_device_reset,
.config_scaling_param = ufs_qcom_config_scaling_param,
.program_key = ufs_qcom_ice_program_key,
};
diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index e221add..2ee905f 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -585,7 +585,20 @@ static void ufshcd_device_reset(struct ufs_hba *hba)
{
int err;
- err = ufshcd_vops_device_reset(hba);
+ err = ufshcd_vops_toggle_device_reset(hba, true);
+ if (err) {
+ dev_err(hba->dev, "device reset pulling down failure: %d\n", err);
+ return;
+ }
+
+ /*
+ * The reset signal is active low. The UFS device
+ * shall detect reset pulses of 1us, sleep for at
+ * least 10us to be on the safe side.
+ */
+ usleep_range(10, 15);
+
+ err = ufshcd_vops_toggle_device_reset(hba, false);
if (!err) {
ufshcd_set_ufs_dev_active(hba);
@@ -593,7 +606,11 @@ static void ufshcd_device_reset(struct ufs_hba *hba)
hba->wb_enabled = false;
hba->wb_buf_flush_enabled = false;
}
+ dev_info(hba->dev, "device reset done\n");
+ } else {
+ dev_err(hba->dev, "device reset pulling up failure: %d\n", err);
}
+
if (err != -EOPNOTSUPP)
ufshcd_update_evt_hist(hba, UFS_EVT_DEV_RESET, err);
}
@@ -8686,8 +8703,6 @@ static int ufshcd_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op)
if (ret)
goto set_dev_active;
- ufshcd_vreg_set_lpm(hba);
-
disable_clks:
/*
* Call vendor specific suspend callback. As these callbacks may access
@@ -8703,6 +8718,9 @@ static int ufshcd_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op)
*/
ufshcd_disable_irq(hba);
+ if (ufshcd_is_link_off(hba))
+ ufshcd_vops_toggle_device_reset(hba, true);
+
ufshcd_setup_clocks(hba, false);
if (ufshcd_is_clkgating_allowed(hba)) {
@@ -8711,6 +8729,8 @@ static int ufshcd_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op)
hba->clk_gating.state);
}
+ ufshcd_vreg_set_lpm(hba);
+
/* Put the host controller in low power mode if possible */
ufshcd_hba_vreg_set_lpm(hba);
goto out;
@@ -8778,18 +8798,19 @@ static int ufshcd_resume(struct ufs_hba *hba, enum ufs_pm_op pm_op)
old_link_state = hba->uic_link_state;
ufshcd_hba_vreg_set_hpm(hba);
+
+ ret = ufshcd_vreg_set_hpm(hba);
+ if (ret)
+ goto out;
+
/* Make sure clocks are enabled before accessing controller */
ret = ufshcd_setup_clocks(hba, true);
if (ret)
- goto out;
+ goto disable_vreg;
/* enable the host irq as host controller would be active soon */
ufshcd_enable_irq(hba);
- ret = ufshcd_vreg_set_hpm(hba);
- if (ret)
- goto disable_irq_and_vops_clks;
-
/*
* Call vendor specific resume callback. As these callbacks may access
* vendor specific host controller register space call them when the
@@ -8797,7 +8818,7 @@ static int ufshcd_resume(struct ufs_hba *hba, enum ufs_pm_op pm_op)
*/
ret = ufshcd_vops_resume(hba, pm_op);
if (ret)
- goto disable_vreg;
+ 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));
@@ -8864,8 +8885,6 @@ static int ufshcd_resume(struct ufs_hba *hba, enum ufs_pm_op pm_op)
ufshcd_link_state_transition(hba, old_link_state, 0);
vendor_suspend:
ufshcd_vops_suspend(hba, pm_op);
-disable_vreg:
- ufshcd_vreg_set_lpm(hba);
disable_irq_and_vops_clks:
ufshcd_disable_irq(hba);
if (hba->clk_scaling.is_allowed)
@@ -8876,6 +8895,8 @@ static int ufshcd_resume(struct ufs_hba *hba, enum ufs_pm_op pm_op)
trace_ufshcd_clk_gating(dev_name(hba->dev),
hba->clk_gating.state);
}
+disable_vreg:
+ ufshcd_vreg_set_lpm(hba);
out:
hba->pm_op_in_progress = 0;
if (ret)
diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
index 9bb5f0e..dccc3eb 100644
--- a/drivers/scsi/ufs/ufshcd.h
+++ b/drivers/scsi/ufs/ufshcd.h
@@ -319,7 +319,7 @@ struct ufs_pwr_mode_info {
* @resume: called during host controller PM callback
* @dbg_register_dump: used to dump controller debug information
* @phy_initialization: used to initialize phys
- * @device_reset: called to issue a reset pulse on the UFS device
+ * @toggle_device_reset: called to change logic level of reset gpio on the UFS device
* @program_key: program or evict an inline encryption key
* @event_notify: called to notify important events
*/
@@ -350,7 +350,7 @@ struct ufs_hba_variant_ops {
int (*resume)(struct ufs_hba *, enum ufs_pm_op);
void (*dbg_register_dump)(struct ufs_hba *hba);
int (*phy_initialization)(struct ufs_hba *);
- int (*device_reset)(struct ufs_hba *hba);
+ int (*toggle_device_reset)(struct ufs_hba *hba, bool down);
void (*config_scaling_param)(struct ufs_hba *hba,
struct devfreq_dev_profile *profile,
void *data);
@@ -1216,10 +1216,10 @@ static inline void ufshcd_vops_dbg_register_dump(struct ufs_hba *hba)
hba->vops->dbg_register_dump(hba);
}
-static inline int ufshcd_vops_device_reset(struct ufs_hba *hba)
+static inline int ufshcd_vops_toggle_device_reset(struct ufs_hba *hba, bool down)
{
- if (hba->vops && hba->vops->device_reset)
- return hba->vops->device_reset(hba);
+ if (hba->vops && hba->vops->toggle_device_reset)
+ return hba->vops->toggle_device_reset(hba, down);
return -EOPNOTSUPP;
}
--
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project
On Mon 21 Dec 01:51 CST 2020, Ziqi Chen wrote:
> As per specs, e.g, JESD220E chapter 7.2, while powering
> off/on the ufs device, RST_N signal and REF_CLK signal
> should be between VSS(Ground) and VCCQ/VCCQ2.
>
> To flexibly control device reset line, re-name the function
> ufschd_vops_device_reset(sturct ufs_hba *hba) to ufshcd_
> vops_toggle_device_reset(sturct ufs_hba *hba, bool down). The
> new parameter "bool down" is used to separate device reset
> line pulling down from pulling up.
>
> Cc: Kiwoong Kim <[email protected]>
> Cc: Stanley Chu <[email protected]>
> Signed-off-by: Ziqi Chen <[email protected]>
> ---
> drivers/scsi/ufs/ufs-mediatek.c | 27 +++++++++-----------------
> drivers/scsi/ufs/ufs-qcom.c | 22 ++++++++++-----------
> drivers/scsi/ufs/ufshcd.c | 43 ++++++++++++++++++++++++++++++-----------
> drivers/scsi/ufs/ufshcd.h | 10 +++++-----
> 4 files changed, 56 insertions(+), 46 deletions(-)
>
> diff --git a/drivers/scsi/ufs/ufs-mediatek.c b/drivers/scsi/ufs/ufs-mediatek.c
> index 80618af..bff2c42 100644
> --- a/drivers/scsi/ufs/ufs-mediatek.c
> +++ b/drivers/scsi/ufs/ufs-mediatek.c
> @@ -841,27 +841,18 @@ static int ufs_mtk_link_startup_notify(struct ufs_hba *hba,
> return ret;
> }
>
> -static int ufs_mtk_device_reset(struct ufs_hba *hba)
> +static int ufs_mtk_toggle_device_reset(struct ufs_hba *hba, bool down)
> {
> struct arm_smccc_res res;
>
> - ufs_mtk_device_reset_ctrl(0, res);
> -
> - /*
> - * The reset signal is active low. UFS devices shall detect
> - * more than or equal to 1us of positive or negative RST_n
> - * pulse width.
> - *
> - * To be on safe side, keep the reset low for at least 10us.
> - */
> - usleep_range(10, 15);
> -
> - ufs_mtk_device_reset_ctrl(1, res);
> -
> - /* Some devices may need time to respond to rst_n */
> - usleep_range(10000, 15000);
> + if (down) {
> + ufs_mtk_device_reset_ctrl(0, res);
> + } else {
> + ufs_mtk_device_reset_ctrl(1, res);
>
> - dev_info(hba->dev, "device reset done\n");
> + /* Some devices may need time to respond to rst_n */
> + usleep_range(10000, 15000);
> + }
>
> return 0;
> }
> @@ -1052,7 +1043,7 @@ static const struct ufs_hba_variant_ops ufs_hba_mtk_vops = {
> .suspend = ufs_mtk_suspend,
> .resume = ufs_mtk_resume,
> .dbg_register_dump = ufs_mtk_dbg_register_dump,
> - .device_reset = ufs_mtk_device_reset,
> + .toggle_device_reset = ufs_mtk_toggle_device_reset,
> .event_notify = ufs_mtk_event_notify,
> };
>
> diff --git a/drivers/scsi/ufs/ufs-qcom.c b/drivers/scsi/ufs/ufs-qcom.c
> index 2206b1e..c2ccaa5 100644
> --- a/drivers/scsi/ufs/ufs-qcom.c
> +++ b/drivers/scsi/ufs/ufs-qcom.c
> @@ -1404,12 +1404,13 @@ static void ufs_qcom_dump_dbg_regs(struct ufs_hba *hba)
> }
>
> /**
> - * ufs_qcom_device_reset() - toggle the (optional) device reset line
> + * ufs_qcom_toggle_device_reset() - toggle the (optional) device reset line
> * @hba: per-adapter instance
> + * @down: pull down or pull up device reset line
> *
> * Toggles the (optional) reset line to reset the attached device.
> */
> -static int ufs_qcom_device_reset(struct ufs_hba *hba)
> +static int ufs_qcom_toggle_device_reset(struct ufs_hba *hba, bool down)
> {
> struct ufs_qcom_host *host = ufshcd_get_variant(hba);
>
> @@ -1417,15 +1418,12 @@ static int ufs_qcom_device_reset(struct ufs_hba *hba)
> if (!host->device_reset)
> return -EOPNOTSUPP;
>
> - /*
> - * The UFS device shall detect reset pulses of 1us, sleep for 10us to
> - * be on the safe side.
> - */
> - gpiod_set_value_cansleep(host->device_reset, 1);
> - usleep_range(10, 15);
> -
> - gpiod_set_value_cansleep(host->device_reset, 0);
> - usleep_range(10, 15);
> + if (down) {
> + gpiod_set_value_cansleep(host->device_reset, 1);
> + } else {
> + gpiod_set_value_cansleep(host->device_reset, 0);
> + usleep_range(10, 15);
The comment above describes that the reset pulse should be 10uS, so the
only reason I can see for the sleep here would be for devices to come
back up after the reset pulse - i.e. what Mediatek believes needs
10-15mS.
As such, I would like you to move this sleep out to the caller and then
turns this snippet into just:
gpiod_set_value_cansleep(host->device_reset, down);
I don't see a problem using Mediatek's reasoning and sleep values in the
common case.
> + }
>
> return 0;
> }
> @@ -1473,7 +1471,7 @@ static const struct ufs_hba_variant_ops ufs_hba_qcom_vops = {
> .suspend = ufs_qcom_suspend,
> .resume = ufs_qcom_resume,
> .dbg_register_dump = ufs_qcom_dump_dbg_regs,
> - .device_reset = ufs_qcom_device_reset,
> + .toggle_device_reset = ufs_qcom_toggle_device_reset,
> .config_scaling_param = ufs_qcom_config_scaling_param,
> .program_key = ufs_qcom_ice_program_key,
> };
> diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
> index e221add..2ee905f 100644
> --- a/drivers/scsi/ufs/ufshcd.c
> +++ b/drivers/scsi/ufs/ufshcd.c
> @@ -585,7 +585,20 @@ static void ufshcd_device_reset(struct ufs_hba *hba)
> {
> int err;
>
> - err = ufshcd_vops_device_reset(hba);
> + err = ufshcd_vops_toggle_device_reset(hba, true);
> + if (err) {
> + dev_err(hba->dev, "device reset pulling down failure: %d\n", err);
"asserting device reset failed"
> + return;
> + }
> +
> + /*
> + * The reset signal is active low. The UFS device
> + * shall detect reset pulses of 1us, sleep for at
> + * least 10us to be on the safe side.
> + */
> + usleep_range(10, 15);
> +
> + err = ufshcd_vops_toggle_device_reset(hba, false);
>
> if (!err) {
> ufshcd_set_ufs_dev_active(hba);
> @@ -593,7 +606,11 @@ static void ufshcd_device_reset(struct ufs_hba *hba)
> hba->wb_enabled = false;
> hba->wb_buf_flush_enabled = false;
> }
> + dev_info(hba->dev, "device reset done\n");
Please use dev_dbg(), as this is only interesting to us when we're
actually debugging UFS related issues.
> + } else {
> + dev_err(hba->dev, "device reset pulling up failure: %d\n", err);
"deasserting device reset failed"
> }
> +
> if (err != -EOPNOTSUPP)
> ufshcd_update_evt_hist(hba, UFS_EVT_DEV_RESET, err);
> }
> @@ -8686,8 +8703,6 @@ static int ufshcd_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op)
> if (ret)
> goto set_dev_active;
>
> - ufshcd_vreg_set_lpm(hba);
> -
> disable_clks:
> /*
> * Call vendor specific suspend callback. As these callbacks may access
> @@ -8703,6 +8718,9 @@ static int ufshcd_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op)
> */
> ufshcd_disable_irq(hba);
>
> + if (ufshcd_is_link_off(hba))
> + ufshcd_vops_toggle_device_reset(hba, true);
> +
> ufshcd_setup_clocks(hba, false);
>
> if (ufshcd_is_clkgating_allowed(hba)) {
> @@ -8711,6 +8729,8 @@ static int ufshcd_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op)
> hba->clk_gating.state);
> }
>
> + ufshcd_vreg_set_lpm(hba);
> +
> /* Put the host controller in low power mode if possible */
> ufshcd_hba_vreg_set_lpm(hba);
> goto out;
> @@ -8778,18 +8798,19 @@ static int ufshcd_resume(struct ufs_hba *hba, enum ufs_pm_op pm_op)
> old_link_state = hba->uic_link_state;
>
> ufshcd_hba_vreg_set_hpm(hba);
> +
> + ret = ufshcd_vreg_set_hpm(hba);
> + if (ret)
> + goto out;
> +
> /* Make sure clocks are enabled before accessing controller */
> ret = ufshcd_setup_clocks(hba, true);
> if (ret)
> - goto out;
> + goto disable_vreg;
>
> /* enable the host irq as host controller would be active soon */
> ufshcd_enable_irq(hba);
>
> - ret = ufshcd_vreg_set_hpm(hba);
> - if (ret)
> - goto disable_irq_and_vops_clks;
> -
> /*
> * Call vendor specific resume callback. As these callbacks may access
> * vendor specific host controller register space call them when the
> @@ -8797,7 +8818,7 @@ static int ufshcd_resume(struct ufs_hba *hba, enum ufs_pm_op pm_op)
> */
> ret = ufshcd_vops_resume(hba, pm_op);
> if (ret)
> - goto disable_vreg;
> + 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));
> @@ -8864,8 +8885,6 @@ static int ufshcd_resume(struct ufs_hba *hba, enum ufs_pm_op pm_op)
> ufshcd_link_state_transition(hba, old_link_state, 0);
> vendor_suspend:
> ufshcd_vops_suspend(hba, pm_op);
> -disable_vreg:
> - ufshcd_vreg_set_lpm(hba);
> disable_irq_and_vops_clks:
> ufshcd_disable_irq(hba);
> if (hba->clk_scaling.is_allowed)
> @@ -8876,6 +8895,8 @@ static int ufshcd_resume(struct ufs_hba *hba, enum ufs_pm_op pm_op)
> trace_ufshcd_clk_gating(dev_name(hba->dev),
> hba->clk_gating.state);
> }
> +disable_vreg:
> + ufshcd_vreg_set_lpm(hba);
> out:
> hba->pm_op_in_progress = 0;
> if (ret)
> diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
> index 9bb5f0e..dccc3eb 100644
> --- a/drivers/scsi/ufs/ufshcd.h
> +++ b/drivers/scsi/ufs/ufshcd.h
> @@ -319,7 +319,7 @@ struct ufs_pwr_mode_info {
> * @resume: called during host controller PM callback
> * @dbg_register_dump: used to dump controller debug information
> * @phy_initialization: used to initialize phys
> - * @device_reset: called to issue a reset pulse on the UFS device
> + * @toggle_device_reset: called to change logic level of reset gpio on the UFS device
> * @program_key: program or evict an inline encryption key
> * @event_notify: called to notify important events
> */
> @@ -350,7 +350,7 @@ struct ufs_hba_variant_ops {
> int (*resume)(struct ufs_hba *, enum ufs_pm_op);
> void (*dbg_register_dump)(struct ufs_hba *hba);
> int (*phy_initialization)(struct ufs_hba *);
> - int (*device_reset)(struct ufs_hba *hba);
> + int (*toggle_device_reset)(struct ufs_hba *hba, bool down);
I don't think "toggle" adds any value to the understanding of what this
function is expected to do, so I would prefer that you just keep it
"device_reset".
I also would prefer that you replace "down" with "asserted" - as this
avoids questions about active high/low etc from the API.
Thanks,
Bjorn
> void (*config_scaling_param)(struct ufs_hba *hba,
> struct devfreq_dev_profile *profile,
> void *data);
> @@ -1216,10 +1216,10 @@ static inline void ufshcd_vops_dbg_register_dump(struct ufs_hba *hba)
> hba->vops->dbg_register_dump(hba);
> }
>
> -static inline int ufshcd_vops_device_reset(struct ufs_hba *hba)
> +static inline int ufshcd_vops_toggle_device_reset(struct ufs_hba *hba, bool down)
> {
> - if (hba->vops && hba->vops->device_reset)
> - return hba->vops->device_reset(hba);
> + if (hba->vops && hba->vops->toggle_device_reset)
> + return hba->vops->toggle_device_reset(hba, down);
>
> return -EOPNOTSUPP;
> }
> --
> The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
> a Linux Foundation Collaborative Project
>
> As per specs, e.g, JESD220E chapter 7.2, while powering off/on the ufs
> device, RST_N signal and REF_CLK signal should be between VSS(Ground) and
> VCCQ/VCCQ2.
>
> To flexibly control device reset line, re-name the function
> ufschd_vops_device_reset(sturct ufs_hba *hba) to ufshcd_
> vops_toggle_device_reset(sturct ufs_hba *hba, bool down). The new
> parameter "bool down" is used to separate device reset line pulling down
> from pulling up.
>
> Cc: Kiwoong Kim <[email protected]>
> Cc: Stanley Chu <[email protected]>
> Signed-off-by: Ziqi Chen <[email protected]>
> ---
> drivers/scsi/ufs/ufs-mediatek.c | 27 +++++++++-----------------
> drivers/scsi/ufs/ufs-qcom.c | 22 ++++++++++-----------
> drivers/scsi/ufs/ufshcd.c | 43 ++++++++++++++++++++++++++++++------
--
> ---
> drivers/scsi/ufs/ufshcd.h | 10 +++++-----
> 4 files changed, 56 insertions(+), 46 deletions(-)
>
> diff --git a/drivers/scsi/ufs/ufs-mediatek.c b/drivers/scsi/ufs/ufs-
> mediatek.c index 80618af..bff2c42 100644
> --- a/drivers/scsi/ufs/ufs-mediatek.c
> +++ b/drivers/scsi/ufs/ufs-mediatek.c
> @@ -841,27 +841,18 @@ static int ufs_mtk_link_startup_notify(struct
> ufs_hba *hba,
> return ret;
> }
>
> -static int ufs_mtk_device_reset(struct ufs_hba *hba)
> +static int ufs_mtk_toggle_device_reset(struct ufs_hba *hba, bool down)
> {
> struct arm_smccc_res res;
>
> - ufs_mtk_device_reset_ctrl(0, res);
> -
> - /*
> - * The reset signal is active low. UFS devices shall detect
> - * more than or equal to 1us of positive or negative RST_n
> - * pulse width.
> - *
> - * To be on safe side, keep the reset low for at least 10us.
> - */
> - usleep_range(10, 15);
> -
> - ufs_mtk_device_reset_ctrl(1, res);
> -
> - /* Some devices may need time to respond to rst_n */
> - usleep_range(10000, 15000);
> + if (down) {
> + ufs_mtk_device_reset_ctrl(0, res);
> + } else {
> + ufs_mtk_device_reset_ctrl(1, res);
>
> - dev_info(hba->dev, "device reset done\n");
> + /* Some devices may need time to respond to rst_n */
> + usleep_range(10000, 15000);
> + }
>
> return 0;
> }
> @@ -1052,7 +1043,7 @@ static const struct ufs_hba_variant_ops
> ufs_hba_mtk_vops = {
> .suspend = ufs_mtk_suspend,
> .resume = ufs_mtk_resume,
> .dbg_register_dump = ufs_mtk_dbg_register_dump,
> - .device_reset = ufs_mtk_device_reset,
> + .toggle_device_reset = ufs_mtk_toggle_device_reset,
> .event_notify = ufs_mtk_event_notify,
> };
>
> diff --git a/drivers/scsi/ufs/ufs-qcom.c b/drivers/scsi/ufs/ufs-qcom.c
> index 2206b1e..c2ccaa5 100644
> --- a/drivers/scsi/ufs/ufs-qcom.c
> +++ b/drivers/scsi/ufs/ufs-qcom.c
> @@ -1404,12 +1404,13 @@ static void ufs_qcom_dump_dbg_regs(struct ufs_hba
> *hba) }
>
> /**
> - * ufs_qcom_device_reset() - toggle the (optional) device reset line
> + * ufs_qcom_toggle_device_reset() - toggle the (optional) device reset
> + line
> * @hba: per-adapter instance
> + * @down: pull down or pull up device reset line
> *
> * Toggles the (optional) reset line to reset the attached device.
> */
> -static int ufs_qcom_device_reset(struct ufs_hba *hba)
> +static int ufs_qcom_toggle_device_reset(struct ufs_hba *hba, bool down)
> {
> struct ufs_qcom_host *host = ufshcd_get_variant(hba);
>
> @@ -1417,15 +1418,12 @@ static int ufs_qcom_device_reset(struct ufs_hba
> *hba)
> if (!host->device_reset)
> return -EOPNOTSUPP;
>
> - /*
> - * The UFS device shall detect reset pulses of 1us, sleep for 10us
> to
> - * be on the safe side.
> - */
> - gpiod_set_value_cansleep(host->device_reset, 1);
> - usleep_range(10, 15);
> -
> - gpiod_set_value_cansleep(host->device_reset, 0);
> - usleep_range(10, 15);
> + if (down) {
> + gpiod_set_value_cansleep(host->device_reset, 1);
> + } else {
> + gpiod_set_value_cansleep(host->device_reset, 0);
> + usleep_range(10, 15);
> + }
>
> return 0;
> }
> @@ -1473,7 +1471,7 @@ static const struct ufs_hba_variant_ops
> ufs_hba_qcom_vops = {
> .suspend = ufs_qcom_suspend,
> .resume = ufs_qcom_resume,
> .dbg_register_dump = ufs_qcom_dump_dbg_regs,
> - .device_reset = ufs_qcom_device_reset,
> + .toggle_device_reset = ufs_qcom_toggle_device_reset,
> .config_scaling_param = ufs_qcom_config_scaling_param,
> .program_key = ufs_qcom_ice_program_key,
> };
> diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c index
> e221add..2ee905f 100644
> --- a/drivers/scsi/ufs/ufshcd.c
> +++ b/drivers/scsi/ufs/ufshcd.c
> @@ -585,7 +585,20 @@ static void ufshcd_device_reset(struct ufs_hba *hba)
> {
> int err;
>
> - err = ufshcd_vops_device_reset(hba);
> + err = ufshcd_vops_toggle_device_reset(hba, true);
> + if (err) {
> + dev_err(hba->dev, "device reset pulling down failure: %d\n",
> err);
> + return;
> + }
> +
> + /*
> + * The reset signal is active low. The UFS device
> + * shall detect reset pulses of 1us, sleep for at
> + * least 10us to be on the safe side.
> + */
> + usleep_range(10, 15);
Is there any point where UFS specification tells this explicitly?
I think this should be moved only if the number, i.e. 10 and 15 just
relies on hardware conditions.
Thanks.
Kiwoong Kim
> + err = ufshcd_vops_toggle_device_reset(hba, false);
>
> if (!err) {
> ufshcd_set_ufs_dev_active(hba);
> @@ -593,7 +606,11 @@ static void ufshcd_device_reset(struct ufs_hba *hba)
> hba->wb_enabled = false;
> hba->wb_buf_flush_enabled = false;
> }
> + dev_info(hba->dev, "device reset done\n");
> + } else {
> + dev_err(hba->dev, "device reset pulling up failure: %d\n",
> err);
> }
> +
> if (err != -EOPNOTSUPP)
> ufshcd_update_evt_hist(hba, UFS_EVT_DEV_RESET, err); } @@ -
> 8686,8 +8703,6 @@ static int ufshcd_suspend(struct ufs_hba *hba, enum
> ufs_pm_op pm_op)
> if (ret)
> goto set_dev_active;
>
> - ufshcd_vreg_set_lpm(hba);
> -
> disable_clks:
> /*
> * Call vendor specific suspend callback. As these callbacks may
> access @@ -8703,6 +8718,9 @@ static int ufshcd_suspend(struct ufs_hba
*hba,
> enum ufs_pm_op pm_op)
> */
> ufshcd_disable_irq(hba);
>
> + if (ufshcd_is_link_off(hba))
> + ufshcd_vops_toggle_device_reset(hba, true);
> +
> ufshcd_setup_clocks(hba, false);
>
> if (ufshcd_is_clkgating_allowed(hba)) { @@ -8711,6 +8729,8 @@
> static int ufshcd_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op)
> hba->clk_gating.state);
> }
>
> + ufshcd_vreg_set_lpm(hba);
> +
> /* Put the host controller in low power mode if possible */
> ufshcd_hba_vreg_set_lpm(hba);
> goto out;
> @@ -8778,18 +8798,19 @@ static int ufshcd_resume(struct ufs_hba *hba, enum
> ufs_pm_op pm_op)
> old_link_state = hba->uic_link_state;
>
> ufshcd_hba_vreg_set_hpm(hba);
> +
> + ret = ufshcd_vreg_set_hpm(hba);
> + if (ret)
> + goto out;
> +
> /* Make sure clocks are enabled before accessing controller */
> ret = ufshcd_setup_clocks(hba, true);
> if (ret)
> - goto out;
> + goto disable_vreg;
>
> /* enable the host irq as host controller would be active soon */
> ufshcd_enable_irq(hba);
>
> - ret = ufshcd_vreg_set_hpm(hba);
> - if (ret)
> - goto disable_irq_and_vops_clks;
> -
> /*
> * Call vendor specific resume callback. As these callbacks may
> access
> * vendor specific host controller register space call them when
> the @@ -8797,7 +8818,7 @@ static int ufshcd_resume(struct ufs_hba *hba,
> enum ufs_pm_op pm_op)
> */
> ret = ufshcd_vops_resume(hba, pm_op);
> if (ret)
> - goto disable_vreg;
> + 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)); @@ -8864,8 +8885,6 @@ static int
> ufshcd_resume(struct ufs_hba *hba, enum ufs_pm_op pm_op)
> ufshcd_link_state_transition(hba, old_link_state, 0);
> vendor_suspend:
> ufshcd_vops_suspend(hba, pm_op);
> -disable_vreg:
> - ufshcd_vreg_set_lpm(hba);
> disable_irq_and_vops_clks:
> ufshcd_disable_irq(hba);
> if (hba->clk_scaling.is_allowed)
> @@ -8876,6 +8895,8 @@ static int ufshcd_resume(struct ufs_hba *hba, enum
> ufs_pm_op pm_op)
> trace_ufshcd_clk_gating(dev_name(hba->dev),
> hba->clk_gating.state);
> }
> +disable_vreg:
> + ufshcd_vreg_set_lpm(hba);
> out:
> hba->pm_op_in_progress = 0;
> if (ret)
> diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h index
> 9bb5f0e..dccc3eb 100644
> --- a/drivers/scsi/ufs/ufshcd.h
> +++ b/drivers/scsi/ufs/ufshcd.h
> @@ -319,7 +319,7 @@ struct ufs_pwr_mode_info {
> * @resume: called during host controller PM callback
> * @dbg_register_dump: used to dump controller debug information
> * @phy_initialization: used to initialize phys
> - * @device_reset: called to issue a reset pulse on the UFS device
> + * @toggle_device_reset: called to change logic level of reset gpio on
> + the UFS device
> * @program_key: program or evict an inline encryption key
> * @event_notify: called to notify important events
> */
> @@ -350,7 +350,7 @@ struct ufs_hba_variant_ops {
> int (*resume)(struct ufs_hba *, enum ufs_pm_op);
> void (*dbg_register_dump)(struct ufs_hba *hba);
> int (*phy_initialization)(struct ufs_hba *);
> - int (*device_reset)(struct ufs_hba *hba);
> + int (*toggle_device_reset)(struct ufs_hba *hba, bool down);
> void (*config_scaling_param)(struct ufs_hba *hba,
> struct devfreq_dev_profile *profile,
> void *data);
> @@ -1216,10 +1216,10 @@ static inline void
> ufshcd_vops_dbg_register_dump(struct ufs_hba *hba)
> hba->vops->dbg_register_dump(hba);
> }
>
> -static inline int ufshcd_vops_device_reset(struct ufs_hba *hba)
> +static inline int ufshcd_vops_toggle_device_reset(struct ufs_hba *hba,
> +bool down)
> {
> - if (hba->vops && hba->vops->device_reset)
> - return hba->vops->device_reset(hba);
> + if (hba->vops && hba->vops->toggle_device_reset)
> + return hba->vops->toggle_device_reset(hba, down);
>
> return -EOPNOTSUPP;
> }
> --
> The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
> a Linux Foundation Collaborative Project
On 2020-12-22 02:41, Bjorn Andersson wrote:
> On Mon 21 Dec 01:51 CST 2020, Ziqi Chen wrote:
>
>> As per specs, e.g, JESD220E chapter 7.2, while powering
>> off/on the ufs device, RST_N signal and REF_CLK signal
>> should be between VSS(Ground) and VCCQ/VCCQ2.
>>
>> To flexibly control device reset line, re-name the function
>> ufschd_vops_device_reset(sturct ufs_hba *hba) to ufshcd_
>> vops_toggle_device_reset(sturct ufs_hba *hba, bool down). The
>> new parameter "bool down" is used to separate device reset
>> line pulling down from pulling up.
>>
>> Cc: Kiwoong Kim <[email protected]>
>> Cc: Stanley Chu <[email protected]>
>> Signed-off-by: Ziqi Chen <[email protected]>
>> ---
>> drivers/scsi/ufs/ufs-mediatek.c | 27 +++++++++-----------------
>> drivers/scsi/ufs/ufs-qcom.c | 22 ++++++++++-----------
>> drivers/scsi/ufs/ufshcd.c | 43
>> ++++++++++++++++++++++++++++++-----------
>> drivers/scsi/ufs/ufshcd.h | 10 +++++-----
>> 4 files changed, 56 insertions(+), 46 deletions(-)
>>
>> diff --git a/drivers/scsi/ufs/ufs-mediatek.c
>> b/drivers/scsi/ufs/ufs-mediatek.c
>> index 80618af..bff2c42 100644
>> --- a/drivers/scsi/ufs/ufs-mediatek.c
>> +++ b/drivers/scsi/ufs/ufs-mediatek.c
>> @@ -841,27 +841,18 @@ static int ufs_mtk_link_startup_notify(struct
>> ufs_hba *hba,
>> return ret;
>> }
>>
>> -static int ufs_mtk_device_reset(struct ufs_hba *hba)
>> +static int ufs_mtk_toggle_device_reset(struct ufs_hba *hba, bool
>> down)
>> {
>> struct arm_smccc_res res;
>>
>> - ufs_mtk_device_reset_ctrl(0, res);
>> -
>> - /*
>> - * The reset signal is active low. UFS devices shall detect
>> - * more than or equal to 1us of positive or negative RST_n
>> - * pulse width.
>> - *
>> - * To be on safe side, keep the reset low for at least 10us.
>> - */
>> - usleep_range(10, 15);
>> -
>> - ufs_mtk_device_reset_ctrl(1, res);
>> -
>> - /* Some devices may need time to respond to rst_n */
>> - usleep_range(10000, 15000);
>> + if (down) {
>> + ufs_mtk_device_reset_ctrl(0, res);
>> + } else {
>> + ufs_mtk_device_reset_ctrl(1, res);
>>
>> - dev_info(hba->dev, "device reset done\n");
>> + /* Some devices may need time to respond to rst_n */
>> + usleep_range(10000, 15000);
>> + }
>>
>> return 0;
>> }
>> @@ -1052,7 +1043,7 @@ static const struct ufs_hba_variant_ops
>> ufs_hba_mtk_vops = {
>> .suspend = ufs_mtk_suspend,
>> .resume = ufs_mtk_resume,
>> .dbg_register_dump = ufs_mtk_dbg_register_dump,
>> - .device_reset = ufs_mtk_device_reset,
>> + .toggle_device_reset = ufs_mtk_toggle_device_reset,
>> .event_notify = ufs_mtk_event_notify,
>> };
>>
>> diff --git a/drivers/scsi/ufs/ufs-qcom.c b/drivers/scsi/ufs/ufs-qcom.c
>> index 2206b1e..c2ccaa5 100644
>> --- a/drivers/scsi/ufs/ufs-qcom.c
>> +++ b/drivers/scsi/ufs/ufs-qcom.c
>> @@ -1404,12 +1404,13 @@ static void ufs_qcom_dump_dbg_regs(struct
>> ufs_hba *hba)
>> }
>>
>> /**
>> - * ufs_qcom_device_reset() - toggle the (optional) device reset line
>> + * ufs_qcom_toggle_device_reset() - toggle the (optional) device
>> reset line
>> * @hba: per-adapter instance
>> + * @down: pull down or pull up device reset line
>> *
>> * Toggles the (optional) reset line to reset the attached device.
>> */
>> -static int ufs_qcom_device_reset(struct ufs_hba *hba)
>> +static int ufs_qcom_toggle_device_reset(struct ufs_hba *hba, bool
>> down)
>> {
>> struct ufs_qcom_host *host = ufshcd_get_variant(hba);
>>
>> @@ -1417,15 +1418,12 @@ static int ufs_qcom_device_reset(struct
>> ufs_hba *hba)
>> if (!host->device_reset)
>> return -EOPNOTSUPP;
>>
>> - /*
>> - * The UFS device shall detect reset pulses of 1us, sleep for 10us
>> to
>> - * be on the safe side.
>> - */
>> - gpiod_set_value_cansleep(host->device_reset, 1);
>> - usleep_range(10, 15);
>> -
>> - gpiod_set_value_cansleep(host->device_reset, 0);
>> - usleep_range(10, 15);
>> + if (down) {
>> + gpiod_set_value_cansleep(host->device_reset, 1);
>> + } else {
>> + gpiod_set_value_cansleep(host->device_reset, 0);
>> + usleep_range(10, 15);
>
> The comment above describes that the reset pulse should be 10uS, so the
> only reason I can see for the sleep here would be for devices to come
> back up after the reset pulse - i.e. what Mediatek believes needs
> 10-15mS.
>
> As such, I would like you to move this sleep out to the caller and then
> turns this snippet into just:
>
> gpiod_set_value_cansleep(host->device_reset, down);
>
> I don't see a problem using Mediatek's reasoning and sleep values in
> the
> common case.
Understood. It would better to move this sleep (10-15ms)out to the
caller and
simplify this function.
>
>> + }
>>
>> return 0;
>> }
>> @@ -1473,7 +1471,7 @@ static const struct ufs_hba_variant_ops
>> ufs_hba_qcom_vops = {
>> .suspend = ufs_qcom_suspend,
>> .resume = ufs_qcom_resume,
>> .dbg_register_dump = ufs_qcom_dump_dbg_regs,
>> - .device_reset = ufs_qcom_device_reset,
>> + .toggle_device_reset = ufs_qcom_toggle_device_reset,
>> .config_scaling_param = ufs_qcom_config_scaling_param,
>> .program_key = ufs_qcom_ice_program_key,
>> };
>> diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
>> index e221add..2ee905f 100644
>> --- a/drivers/scsi/ufs/ufshcd.c
>> +++ b/drivers/scsi/ufs/ufshcd.c
>> @@ -585,7 +585,20 @@ static void ufshcd_device_reset(struct ufs_hba
>> *hba)
>> {
>> int err;
>>
>> - err = ufshcd_vops_device_reset(hba);
>> + err = ufshcd_vops_toggle_device_reset(hba, true);
>> + if (err) {
>> + dev_err(hba->dev, "device reset pulling down failure: %d\n", err);
>
> "asserting device reset failed"
Agree, thanks.
>
>> + return;
>> + }
>> +
>> + /*
>> + * The reset signal is active low. The UFS device
>> + * shall detect reset pulses of 1us, sleep for at
>> + * least 10us to be on the safe side.
>> + */
>> + usleep_range(10, 15);
>> +
>> + err = ufshcd_vops_toggle_device_reset(hba, false);
>>
>> if (!err) {
>> ufshcd_set_ufs_dev_active(hba);
>> @@ -593,7 +606,11 @@ static void ufshcd_device_reset(struct ufs_hba
>> *hba)
>> hba->wb_enabled = false;
>> hba->wb_buf_flush_enabled = false;
>> }
>> + dev_info(hba->dev, "device reset done\n");
>
> Please use dev_dbg(), as this is only interesting to us when we're
> actually debugging UFS related issues.
Agree, thanks.
>
>> + } else {
>> + dev_err(hba->dev, "device reset pulling up failure: %d\n", err);
>
> "deasserting device reset failed"
Agree, thanks.
>
>> }
>> +
>> if (err != -EOPNOTSUPP)
>> ufshcd_update_evt_hist(hba, UFS_EVT_DEV_RESET, err);
>> }
>> @@ -8686,8 +8703,6 @@ static int ufshcd_suspend(struct ufs_hba *hba,
>> enum ufs_pm_op pm_op)
>> if (ret)
>> goto set_dev_active;
>>
>> - ufshcd_vreg_set_lpm(hba);
>> -
>> disable_clks:
>> /*
>> * Call vendor specific suspend callback. As these callbacks may
>> access
>> @@ -8703,6 +8718,9 @@ static int ufshcd_suspend(struct ufs_hba *hba,
>> enum ufs_pm_op pm_op)
>> */
>> ufshcd_disable_irq(hba);
>>
>> + if (ufshcd_is_link_off(hba))
>> + ufshcd_vops_toggle_device_reset(hba, true);
>> +
>> ufshcd_setup_clocks(hba, false);
>>
>> if (ufshcd_is_clkgating_allowed(hba)) {
>> @@ -8711,6 +8729,8 @@ static int ufshcd_suspend(struct ufs_hba *hba,
>> enum ufs_pm_op pm_op)
>> hba->clk_gating.state);
>> }
>>
>> + ufshcd_vreg_set_lpm(hba);
>> +
>> /* Put the host controller in low power mode if possible */
>> ufshcd_hba_vreg_set_lpm(hba);
>> goto out;
>> @@ -8778,18 +8798,19 @@ static int ufshcd_resume(struct ufs_hba *hba,
>> enum ufs_pm_op pm_op)
>> old_link_state = hba->uic_link_state;
>>
>> ufshcd_hba_vreg_set_hpm(hba);
>> +
>> + ret = ufshcd_vreg_set_hpm(hba);
>> + if (ret)
>> + goto out;
>> +
>> /* Make sure clocks are enabled before accessing controller */
>> ret = ufshcd_setup_clocks(hba, true);
>> if (ret)
>> - goto out;
>> + goto disable_vreg;
>>
>> /* enable the host irq as host controller would be active soon */
>> ufshcd_enable_irq(hba);
>>
>> - ret = ufshcd_vreg_set_hpm(hba);
>> - if (ret)
>> - goto disable_irq_and_vops_clks;
>> -
>> /*
>> * Call vendor specific resume callback. As these callbacks may
>> access
>> * vendor specific host controller register space call them when the
>> @@ -8797,7 +8818,7 @@ static int ufshcd_resume(struct ufs_hba *hba,
>> enum ufs_pm_op pm_op)
>> */
>> ret = ufshcd_vops_resume(hba, pm_op);
>> if (ret)
>> - goto disable_vreg;
>> + 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));
>> @@ -8864,8 +8885,6 @@ static int ufshcd_resume(struct ufs_hba *hba,
>> enum ufs_pm_op pm_op)
>> ufshcd_link_state_transition(hba, old_link_state, 0);
>> vendor_suspend:
>> ufshcd_vops_suspend(hba, pm_op);
>> -disable_vreg:
>> - ufshcd_vreg_set_lpm(hba);
>> disable_irq_and_vops_clks:
>> ufshcd_disable_irq(hba);
>> if (hba->clk_scaling.is_allowed)
>> @@ -8876,6 +8895,8 @@ static int ufshcd_resume(struct ufs_hba *hba,
>> enum ufs_pm_op pm_op)
>> trace_ufshcd_clk_gating(dev_name(hba->dev),
>> hba->clk_gating.state);
>> }
>> +disable_vreg:
>> + ufshcd_vreg_set_lpm(hba);
>> out:
>> hba->pm_op_in_progress = 0;
>> if (ret)
>> diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
>> index 9bb5f0e..dccc3eb 100644
>> --- a/drivers/scsi/ufs/ufshcd.h
>> +++ b/drivers/scsi/ufs/ufshcd.h
>> @@ -319,7 +319,7 @@ struct ufs_pwr_mode_info {
>> * @resume: called during host controller PM callback
>> * @dbg_register_dump: used to dump controller debug information
>> * @phy_initialization: used to initialize phys
>> - * @device_reset: called to issue a reset pulse on the UFS device
>> + * @toggle_device_reset: called to change logic level of reset gpio
>> on the UFS device
>> * @program_key: program or evict an inline encryption key
>> * @event_notify: called to notify important events
>> */
>> @@ -350,7 +350,7 @@ struct ufs_hba_variant_ops {
>> int (*resume)(struct ufs_hba *, enum ufs_pm_op);
>> void (*dbg_register_dump)(struct ufs_hba *hba);
>> int (*phy_initialization)(struct ufs_hba *);
>> - int (*device_reset)(struct ufs_hba *hba);
>> + int (*toggle_device_reset)(struct ufs_hba *hba, bool down);
>
> I don't think "toggle" adds any value to the understanding of what this
> function is expected to do, so I would prefer that you just keep it
> "device_reset".
>
> I also would prefer that you replace "down" with "asserted" - as this
> avoids questions about active high/low etc from the API.
>
> Thanks,
> Bjorn
Agree, thanks.
Best Regards,
Ziqi
>
>> void (*config_scaling_param)(struct ufs_hba *hba,
>> struct devfreq_dev_profile *profile,
>> void *data);
>> @@ -1216,10 +1216,10 @@ static inline void
>> ufshcd_vops_dbg_register_dump(struct ufs_hba *hba)
>> hba->vops->dbg_register_dump(hba);
>> }
>>
>> -static inline int ufshcd_vops_device_reset(struct ufs_hba *hba)
>> +static inline int ufshcd_vops_toggle_device_reset(struct ufs_hba
>> *hba, bool down)
>> {
>> - if (hba->vops && hba->vops->device_reset)
>> - return hba->vops->device_reset(hba);
>> + if (hba->vops && hba->vops->toggle_device_reset)
>> + return hba->vops->toggle_device_reset(hba, down);
>>
>> return -EOPNOTSUPP;
>> }
>> --
>> The Qualcomm Innovation Center, Inc. is a member of the Code Aurora
>> Forum,
>> a Linux Foundation Collaborative Project
>>
On 2020-12-22 10:04, Kiwoong Kim wrote:
>> As per specs, e.g, JESD220E chapter 7.2, while powering off/on the ufs
>> device, RST_N signal and REF_CLK signal should be between VSS(Ground)
>> and
>> VCCQ/VCCQ2.
>>
>> To flexibly control device reset line, re-name the function
>> ufschd_vops_device_reset(sturct ufs_hba *hba) to ufshcd_
>> vops_toggle_device_reset(sturct ufs_hba *hba, bool down). The new
>> parameter "bool down" is used to separate device reset line pulling
>> down
>> from pulling up.
>>
>> Cc: Kiwoong Kim <[email protected]>
>> Cc: Stanley Chu <[email protected]>
>> Signed-off-by: Ziqi Chen <[email protected]>
>> ---
>> drivers/scsi/ufs/ufs-mediatek.c | 27 +++++++++-----------------
>> drivers/scsi/ufs/ufs-qcom.c | 22 ++++++++++-----------
>> drivers/scsi/ufs/ufshcd.c | 43
>> ++++++++++++++++++++++++++++++------
> --
>> ---
>> drivers/scsi/ufs/ufshcd.h | 10 +++++-----
>> 4 files changed, 56 insertions(+), 46 deletions(-)
>>
>> diff --git a/drivers/scsi/ufs/ufs-mediatek.c b/drivers/scsi/ufs/ufs-
>> mediatek.c index 80618af..bff2c42 100644
>> --- a/drivers/scsi/ufs/ufs-mediatek.c
>> +++ b/drivers/scsi/ufs/ufs-mediatek.c
>> @@ -841,27 +841,18 @@ static int ufs_mtk_link_startup_notify(struct
>> ufs_hba *hba,
>> return ret;
>> }
>>
>> -static int ufs_mtk_device_reset(struct ufs_hba *hba)
>> +static int ufs_mtk_toggle_device_reset(struct ufs_hba *hba, bool
>> down)
>> {
>> struct arm_smccc_res res;
>>
>> - ufs_mtk_device_reset_ctrl(0, res);
>> -
>> - /*
>> - * The reset signal is active low. UFS devices shall detect
>> - * more than or equal to 1us of positive or negative RST_n
>> - * pulse width.
>> - *
>> - * To be on safe side, keep the reset low for at least 10us.
>> - */
>> - usleep_range(10, 15);
>> -
>> - ufs_mtk_device_reset_ctrl(1, res);
>> -
>> - /* Some devices may need time to respond to rst_n */
>> - usleep_range(10000, 15000);
>> + if (down) {
>> + ufs_mtk_device_reset_ctrl(0, res);
>> + } else {
>> + ufs_mtk_device_reset_ctrl(1, res);
>>
>> - dev_info(hba->dev, "device reset done\n");
>> + /* Some devices may need time to respond to rst_n */
>> + usleep_range(10000, 15000);
>> + }
>>
>> return 0;
>> }
>> @@ -1052,7 +1043,7 @@ static const struct ufs_hba_variant_ops
>> ufs_hba_mtk_vops = {
>> .suspend = ufs_mtk_suspend,
>> .resume = ufs_mtk_resume,
>> .dbg_register_dump = ufs_mtk_dbg_register_dump,
>> - .device_reset = ufs_mtk_device_reset,
>> + .toggle_device_reset = ufs_mtk_toggle_device_reset,
>> .event_notify = ufs_mtk_event_notify,
>> };
>>
>> diff --git a/drivers/scsi/ufs/ufs-qcom.c b/drivers/scsi/ufs/ufs-qcom.c
>> index 2206b1e..c2ccaa5 100644
>> --- a/drivers/scsi/ufs/ufs-qcom.c
>> +++ b/drivers/scsi/ufs/ufs-qcom.c
>> @@ -1404,12 +1404,13 @@ static void ufs_qcom_dump_dbg_regs(struct
>> ufs_hba
>> *hba) }
>>
>> /**
>> - * ufs_qcom_device_reset() - toggle the (optional) device reset line
>> + * ufs_qcom_toggle_device_reset() - toggle the (optional) device
>> reset
>> + line
>> * @hba: per-adapter instance
>> + * @down: pull down or pull up device reset line
>> *
>> * Toggles the (optional) reset line to reset the attached device.
>> */
>> -static int ufs_qcom_device_reset(struct ufs_hba *hba)
>> +static int ufs_qcom_toggle_device_reset(struct ufs_hba *hba, bool
>> down)
>> {
>> struct ufs_qcom_host *host = ufshcd_get_variant(hba);
>>
>> @@ -1417,15 +1418,12 @@ static int ufs_qcom_device_reset(struct
>> ufs_hba
>> *hba)
>> if (!host->device_reset)
>> return -EOPNOTSUPP;
>>
>> - /*
>> - * The UFS device shall detect reset pulses of 1us, sleep for 10us
>> to
>> - * be on the safe side.
>> - */
>> - gpiod_set_value_cansleep(host->device_reset, 1);
>> - usleep_range(10, 15);
>> -
>> - gpiod_set_value_cansleep(host->device_reset, 0);
>> - usleep_range(10, 15);
>> + if (down) {
>> + gpiod_set_value_cansleep(host->device_reset, 1);
>> + } else {
>> + gpiod_set_value_cansleep(host->device_reset, 0);
>> + usleep_range(10, 15);
>> + }
>>
>> return 0;
>> }
>> @@ -1473,7 +1471,7 @@ static const struct ufs_hba_variant_ops
>> ufs_hba_qcom_vops = {
>> .suspend = ufs_qcom_suspend,
>> .resume = ufs_qcom_resume,
>> .dbg_register_dump = ufs_qcom_dump_dbg_regs,
>> - .device_reset = ufs_qcom_device_reset,
>> + .toggle_device_reset = ufs_qcom_toggle_device_reset,
>> .config_scaling_param = ufs_qcom_config_scaling_param,
>> .program_key = ufs_qcom_ice_program_key,
>> };
>> diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
>> index
>> e221add..2ee905f 100644
>> --- a/drivers/scsi/ufs/ufshcd.c
>> +++ b/drivers/scsi/ufs/ufshcd.c
>> @@ -585,7 +585,20 @@ static void ufshcd_device_reset(struct ufs_hba
>> *hba)
>> {
>> int err;
>>
>> - err = ufshcd_vops_device_reset(hba);
>> + err = ufshcd_vops_toggle_device_reset(hba, true);
>> + if (err) {
>> + dev_err(hba->dev, "device reset pulling down failure: %d\n",
>> err);
>> + return;
>> + }
>> +
>> + /*
>> + * The reset signal is active low. The UFS device
>> + * shall detect reset pulses of 1us, sleep for at
>> + * least 10us to be on the safe side.
>> + */
>> + usleep_range(10, 15);
>
> Is there any point where UFS specification tells this explicitly?
> I think this should be moved only if the number, i.e. 10 and 15 just
> relies on hardware conditions.
>
>
> Thanks.
> Kiwoong Kim
Hi Kiwoong,
Thanks for your comment. JESD220E Line 610~611 "The UFS device shall
detect more than or equal to 1us
of positive or negative RST_n pulse". Both QCOM and Mediatek use
10~15us. What
number do you think more appropriate?
Best Regards,
Ziqi
>
>> + err = ufshcd_vops_toggle_device_reset(hba, false);
>>
>> if (!err) {
>> ufshcd_set_ufs_dev_active(hba);
>> @@ -593,7 +606,11 @@ static void ufshcd_device_reset(struct ufs_hba
>> *hba)
>> hba->wb_enabled = false;
>> hba->wb_buf_flush_enabled = false;
>> }
>> + dev_info(hba->dev, "device reset done\n");
>> + } else {
>> + dev_err(hba->dev, "device reset pulling up failure: %d\n",
>> err);
>> }
>> +
>> if (err != -EOPNOTSUPP)
>> ufshcd_update_evt_hist(hba, UFS_EVT_DEV_RESET, err); } @@ -
>> 8686,8 +8703,6 @@ static int ufshcd_suspend(struct ufs_hba *hba, enum
>> ufs_pm_op pm_op)
>> if (ret)
>> goto set_dev_active;
>>
>> - ufshcd_vreg_set_lpm(hba);
>> -
>> disable_clks:
>> /*
>> * Call vendor specific suspend callback. As these callbacks may
>> access @@ -8703,6 +8718,9 @@ static int ufshcd_suspend(struct ufs_hba
>> *hba,
>> enum ufs_pm_op pm_op)
>> */
>> ufshcd_disable_irq(hba);
>>
>> + if (ufshcd_is_link_off(hba))
>> + ufshcd_vops_toggle_device_reset(hba, true);
>> +
>> ufshcd_setup_clocks(hba, false);
>>
>> if (ufshcd_is_clkgating_allowed(hba)) { @@ -8711,6 +8729,8 @@
>> static int ufshcd_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op)
>> hba->clk_gating.state);
>> }
>>
>> + ufshcd_vreg_set_lpm(hba);
>> +
>> /* Put the host controller in low power mode if possible */
>> ufshcd_hba_vreg_set_lpm(hba);
>> goto out;
>> @@ -8778,18 +8798,19 @@ static int ufshcd_resume(struct ufs_hba *hba,
>> enum
>> ufs_pm_op pm_op)
>> old_link_state = hba->uic_link_state;
>>
>> ufshcd_hba_vreg_set_hpm(hba);
>> +
>> + ret = ufshcd_vreg_set_hpm(hba);
>> + if (ret)
>> + goto out;
>> +
>> /* Make sure clocks are enabled before accessing controller */
>> ret = ufshcd_setup_clocks(hba, true);
>> if (ret)
>> - goto out;
>> + goto disable_vreg;
>>
>> /* enable the host irq as host controller would be active soon */
>> ufshcd_enable_irq(hba);
>>
>> - ret = ufshcd_vreg_set_hpm(hba);
>> - if (ret)
>> - goto disable_irq_and_vops_clks;
>> -
>> /*
>> * Call vendor specific resume callback. As these callbacks may
>> access
>> * vendor specific host controller register space call them when
>> the @@ -8797,7 +8818,7 @@ static int ufshcd_resume(struct ufs_hba
>> *hba,
>> enum ufs_pm_op pm_op)
>> */
>> ret = ufshcd_vops_resume(hba, pm_op);
>> if (ret)
>> - goto disable_vreg;
>> + 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)); @@ -8864,8 +8885,6 @@ static int
>> ufshcd_resume(struct ufs_hba *hba, enum ufs_pm_op pm_op)
>> ufshcd_link_state_transition(hba, old_link_state, 0);
>> vendor_suspend:
>> ufshcd_vops_suspend(hba, pm_op);
>> -disable_vreg:
>> - ufshcd_vreg_set_lpm(hba);
>> disable_irq_and_vops_clks:
>> ufshcd_disable_irq(hba);
>> if (hba->clk_scaling.is_allowed)
>> @@ -8876,6 +8895,8 @@ static int ufshcd_resume(struct ufs_hba *hba,
>> enum
>> ufs_pm_op pm_op)
>> trace_ufshcd_clk_gating(dev_name(hba->dev),
>> hba->clk_gating.state);
>> }
>> +disable_vreg:
>> + ufshcd_vreg_set_lpm(hba);
>> out:
>> hba->pm_op_in_progress = 0;
>> if (ret)
>> diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
>> index
>> 9bb5f0e..dccc3eb 100644
>> --- a/drivers/scsi/ufs/ufshcd.h
>> +++ b/drivers/scsi/ufs/ufshcd.h
>> @@ -319,7 +319,7 @@ struct ufs_pwr_mode_info {
>> * @resume: called during host controller PM callback
>> * @dbg_register_dump: used to dump controller debug information
>> * @phy_initialization: used to initialize phys
>> - * @device_reset: called to issue a reset pulse on the UFS device
>> + * @toggle_device_reset: called to change logic level of reset gpio
>> on
>> + the UFS device
>> * @program_key: program or evict an inline encryption key
>> * @event_notify: called to notify important events
>> */
>> @@ -350,7 +350,7 @@ struct ufs_hba_variant_ops {
>> int (*resume)(struct ufs_hba *, enum ufs_pm_op);
>> void (*dbg_register_dump)(struct ufs_hba *hba);
>> int (*phy_initialization)(struct ufs_hba *);
>> - int (*device_reset)(struct ufs_hba *hba);
>> + int (*toggle_device_reset)(struct ufs_hba *hba, bool down);
>> void (*config_scaling_param)(struct ufs_hba *hba,
>> struct devfreq_dev_profile *profile,
>> void *data);
>> @@ -1216,10 +1216,10 @@ static inline void
>> ufshcd_vops_dbg_register_dump(struct ufs_hba *hba)
>> hba->vops->dbg_register_dump(hba);
>> }
>>
>> -static inline int ufshcd_vops_device_reset(struct ufs_hba *hba)
>> +static inline int ufshcd_vops_toggle_device_reset(struct ufs_hba
>> *hba,
>> +bool down)
>> {
>> - if (hba->vops && hba->vops->device_reset)
>> - return hba->vops->device_reset(hba);
>> + if (hba->vops && hba->vops->toggle_device_reset)
>> + return hba->vops->toggle_device_reset(hba, down);
>>
>> return -EOPNOTSUPP;
>> }
>> --
>> The Qualcomm Innovation Center, Inc. is a member of the Code Aurora
>> Forum,
>> a Linux Foundation Collaborative Project
> On 2020-12-22 10:04, Kiwoong Kim wrote:
> >> As per specs, e.g, JESD220E chapter 7.2, while powering off/on the
> >> ufs device, RST_N signal and REF_CLK signal should be between
> >> VSS(Ground) and VCCQ/VCCQ2.
> >>
> >> To flexibly control device reset line, re-name the function
> >> ufschd_vops_device_reset(sturct ufs_hba *hba) to ufshcd_
> >> vops_toggle_device_reset(sturct ufs_hba *hba, bool down). The new
> >> parameter "bool down" is used to separate device reset line pulling
> >> down from pulling up.
> >>
> >> Cc: Kiwoong Kim <[email protected]>
> >> Cc: Stanley Chu <[email protected]>
> >> Signed-off-by: Ziqi Chen <[email protected]>
> >> ---
> >> drivers/scsi/ufs/ufs-mediatek.c | 27 +++++++++-----------------
> >> drivers/scsi/ufs/ufs-qcom.c | 22 ++++++++++-----------
> >> drivers/scsi/ufs/ufshcd.c | 43
> >> ++++++++++++++++++++++++++++++------
> > --
> >> ---
> >> drivers/scsi/ufs/ufshcd.h | 10 +++++-----
> >> 4 files changed, 56 insertions(+), 46 deletions(-)
> >>
> >> diff --git a/drivers/scsi/ufs/ufs-mediatek.c b/drivers/scsi/ufs/ufs-
> >> mediatek.c index 80618af..bff2c42 100644
> >> --- a/drivers/scsi/ufs/ufs-mediatek.c
> >> +++ b/drivers/scsi/ufs/ufs-mediatek.c
> >> @@ -841,27 +841,18 @@ static int ufs_mtk_link_startup_notify(struct
> >> ufs_hba *hba,
> >> return ret;
> >> }
> >>
> >> -static int ufs_mtk_device_reset(struct ufs_hba *hba)
> >> +static int ufs_mtk_toggle_device_reset(struct ufs_hba *hba, bool
> >> down)
> >> {
> >> struct arm_smccc_res res;
> >>
> >> - ufs_mtk_device_reset_ctrl(0, res);
> >> -
> >> - /*
> >> - * The reset signal is active low. UFS devices shall detect
> >> - * more than or equal to 1us of positive or negative RST_n
> >> - * pulse width.
> >> - *
> >> - * To be on safe side, keep the reset low for at least 10us.
> >> - */
> >> - usleep_range(10, 15);
> >> -
> >> - ufs_mtk_device_reset_ctrl(1, res);
> >> -
> >> - /* Some devices may need time to respond to rst_n */
> >> - usleep_range(10000, 15000);
> >> + if (down) {
> >> + ufs_mtk_device_reset_ctrl(0, res);
> >> + } else {
> >> + ufs_mtk_device_reset_ctrl(1, res);
> >>
> >> - dev_info(hba->dev, "device reset done\n");
> >> + /* Some devices may need time to respond to rst_n */
> >> + usleep_range(10000, 15000);
> >> + }
> >>
> >> return 0;
> >> }
> >> @@ -1052,7 +1043,7 @@ static const struct ufs_hba_variant_ops
> >> ufs_hba_mtk_vops = {
> >> .suspend = ufs_mtk_suspend,
> >> .resume = ufs_mtk_resume,
> >> .dbg_register_dump = ufs_mtk_dbg_register_dump,
> >> - .device_reset = ufs_mtk_device_reset,
> >> + .toggle_device_reset = ufs_mtk_toggle_device_reset,
> >> .event_notify = ufs_mtk_event_notify,
> >> };
> >>
> >> diff --git a/drivers/scsi/ufs/ufs-qcom.c
> >> b/drivers/scsi/ufs/ufs-qcom.c index 2206b1e..c2ccaa5 100644
> >> --- a/drivers/scsi/ufs/ufs-qcom.c
> >> +++ b/drivers/scsi/ufs/ufs-qcom.c
> >> @@ -1404,12 +1404,13 @@ static void ufs_qcom_dump_dbg_regs(struct
> >> ufs_hba
> >> *hba) }
> >>
> >> /**
> >> - * ufs_qcom_device_reset() - toggle the (optional) device reset line
> >> + * ufs_qcom_toggle_device_reset() - toggle the (optional) device
> >> reset
> >> + line
> >> * @hba: per-adapter instance
> >> + * @down: pull down or pull up device reset line
> >> *
> >> * Toggles the (optional) reset line to reset the attached device.
> >> */
> >> -static int ufs_qcom_device_reset(struct ufs_hba *hba)
> >> +static int ufs_qcom_toggle_device_reset(struct ufs_hba *hba, bool
> >> down)
> >> {
> >> struct ufs_qcom_host *host = ufshcd_get_variant(hba);
> >>
> >> @@ -1417,15 +1418,12 @@ static int ufs_qcom_device_reset(struct
> >> ufs_hba
> >> *hba)
> >> if (!host->device_reset)
> >> return -EOPNOTSUPP;
> >>
> >> - /*
> >> - * The UFS device shall detect reset pulses of 1us, sleep for 10us
> >> to
> >> - * be on the safe side.
> >> - */
> >> - gpiod_set_value_cansleep(host->device_reset, 1);
> >> - usleep_range(10, 15);
> >> -
> >> - gpiod_set_value_cansleep(host->device_reset, 0);
> >> - usleep_range(10, 15);
> >> + if (down) {
> >> + gpiod_set_value_cansleep(host->device_reset, 1);
> >> + } else {
> >> + gpiod_set_value_cansleep(host->device_reset, 0);
> >> + usleep_range(10, 15);
> >> + }
> >>
> >> return 0;
> >> }
> >> @@ -1473,7 +1471,7 @@ static const struct ufs_hba_variant_ops
> >> ufs_hba_qcom_vops = {
> >> .suspend = ufs_qcom_suspend,
> >> .resume = ufs_qcom_resume,
> >> .dbg_register_dump = ufs_qcom_dump_dbg_regs,
> >> - .device_reset = ufs_qcom_device_reset,
> >> + .toggle_device_reset = ufs_qcom_toggle_device_reset,
> >> .config_scaling_param = ufs_qcom_config_scaling_param,
> >> .program_key = ufs_qcom_ice_program_key,
> >> };
> >> diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
> >> index e221add..2ee905f 100644
> >> --- a/drivers/scsi/ufs/ufshcd.c
> >> +++ b/drivers/scsi/ufs/ufshcd.c
> >> @@ -585,7 +585,20 @@ static void ufshcd_device_reset(struct ufs_hba
> >> *hba)
> >> {
> >> int err;
> >>
> >> - err = ufshcd_vops_device_reset(hba);
> >> + err = ufshcd_vops_toggle_device_reset(hba, true);
> >> + if (err) {
> >> + dev_err(hba->dev, "device reset pulling down failure: %d\n",
> >> err);
> >> + return;
> >> + }
> >> +
> >> + /*
> >> + * The reset signal is active low. The UFS device
> >> + * shall detect reset pulses of 1us, sleep for at
> >> + * least 10us to be on the safe side.
> >> + */
> >> + usleep_range(10, 15);
> >
> > Is there any point where UFS specification tells this explicitly?
> > I think this should be moved only if the number, i.e. 10 and 15 just
> > relies on hardware conditions.
> >
> >
> > Thanks.
> > Kiwoong Kim
>
> Hi Kiwoong,
>
> Thanks for your comment. JESD220E Line 610~611 "The UFS device shall
> detect more than or equal to 1us of positive or negative RST_n pulse".
> Both QCOM and Mediatek use 10~15us. What number do you think more
> appropriate?
>
> Best Regards,
> Ziqi
With yours, all the SoC vendors should wait for around 10us unconditionally
even if there will be a possibility that some can use shorter period.
I see this as a sort of optimization point.
Thanks.
Kiwoong Kim
>
> >
> >> + err = ufshcd_vops_toggle_device_reset(hba, false);
> >>
> >> if (!err) {
> >> ufshcd_set_ufs_dev_active(hba);
> >> @@ -593,7 +606,11 @@ static void ufshcd_device_reset(struct ufs_hba
> >> *hba)
> >> hba->wb_enabled = false;
> >> hba->wb_buf_flush_enabled = false;
> >> }
> >> + dev_info(hba->dev, "device reset done\n");
> >> + } else {
> >> + dev_err(hba->dev, "device reset pulling up failure: %d\n",
> >> err);
> >> }
> >> +
> >> if (err != -EOPNOTSUPP)
> >> ufshcd_update_evt_hist(hba, UFS_EVT_DEV_RESET, err); } @@ -
> >> 8686,8 +8703,6 @@ static int ufshcd_suspend(struct ufs_hba *hba, enum
> >> ufs_pm_op pm_op)
> >> if (ret)
> >> goto set_dev_active;
> >>
> >> - ufshcd_vreg_set_lpm(hba);
> >> -
> >> disable_clks:
> >> /*
> >> * Call vendor specific suspend callback. As these callbacks may
> >> access @@ -8703,6 +8718,9 @@ static int ufshcd_suspend(struct ufs_hba
> >> *hba, enum ufs_pm_op pm_op)
> >> */
> >> ufshcd_disable_irq(hba);
> >>
> >> + if (ufshcd_is_link_off(hba))
> >> + ufshcd_vops_toggle_device_reset(hba, true);
> >> +
> >> ufshcd_setup_clocks(hba, false);
> >>
> >> if (ufshcd_is_clkgating_allowed(hba)) { @@ -8711,6 +8729,8 @@
> >> static int ufshcd_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op)
> >> hba->clk_gating.state);
> >> }
> >>
> >> + ufshcd_vreg_set_lpm(hba);
> >> +
> >> /* Put the host controller in low power mode if possible */
> >> ufshcd_hba_vreg_set_lpm(hba);
> >> goto out;
> >> @@ -8778,18 +8798,19 @@ static int ufshcd_resume(struct ufs_hba *hba,
> >> enum ufs_pm_op pm_op)
> >> old_link_state = hba->uic_link_state;
> >>
> >> ufshcd_hba_vreg_set_hpm(hba);
> >> +
> >> + ret = ufshcd_vreg_set_hpm(hba);
> >> + if (ret)
> >> + goto out;
> >> +
> >> /* Make sure clocks are enabled before accessing controller */
> >> ret = ufshcd_setup_clocks(hba, true);
> >> if (ret)
> >> - goto out;
> >> + goto disable_vreg;
> >>
> >> /* enable the host irq as host controller would be active soon */
> >> ufshcd_enable_irq(hba);
> >>
> >> - ret = ufshcd_vreg_set_hpm(hba);
> >> - if (ret)
> >> - goto disable_irq_and_vops_clks;
> >> -
> >> /*
> >> * Call vendor specific resume callback. As these callbacks may
> >> access
> >> * vendor specific host controller register space call them when
> >> the @@ -8797,7 +8818,7 @@ static int ufshcd_resume(struct ufs_hba
> >> *hba, enum ufs_pm_op pm_op)
> >> */
> >> ret = ufshcd_vops_resume(hba, pm_op);
> >> if (ret)
> >> - goto disable_vreg;
> >> + 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)); @@ -8864,8 +8885,6 @@ static int
> >> ufshcd_resume(struct ufs_hba *hba, enum ufs_pm_op pm_op)
> >> ufshcd_link_state_transition(hba, old_link_state, 0);
> >> vendor_suspend:
> >> ufshcd_vops_suspend(hba, pm_op);
> >> -disable_vreg:
> >> - ufshcd_vreg_set_lpm(hba);
> >> disable_irq_and_vops_clks:
> >> ufshcd_disable_irq(hba);
> >> if (hba->clk_scaling.is_allowed)
> >> @@ -8876,6 +8895,8 @@ static int ufshcd_resume(struct ufs_hba *hba,
> >> enum ufs_pm_op pm_op)
> >> trace_ufshcd_clk_gating(dev_name(hba->dev),
> >> hba->clk_gating.state);
> >> }
> >> +disable_vreg:
> >> + ufshcd_vreg_set_lpm(hba);
> >> out:
> >> hba->pm_op_in_progress = 0;
> >> if (ret)
> >> diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
> >> index 9bb5f0e..dccc3eb 100644
> >> --- a/drivers/scsi/ufs/ufshcd.h
> >> +++ b/drivers/scsi/ufs/ufshcd.h
> >> @@ -319,7 +319,7 @@ struct ufs_pwr_mode_info {
> >> * @resume: called during host controller PM callback
> >> * @dbg_register_dump: used to dump controller debug information
> >> * @phy_initialization: used to initialize phys
> >> - * @device_reset: called to issue a reset pulse on the UFS device
> >> + * @toggle_device_reset: called to change logic level of reset gpio
> >> on
> >> + the UFS device
> >> * @program_key: program or evict an inline encryption key
> >> * @event_notify: called to notify important events
> >> */
> >> @@ -350,7 +350,7 @@ struct ufs_hba_variant_ops {
> >> int (*resume)(struct ufs_hba *, enum ufs_pm_op);
> >> void (*dbg_register_dump)(struct ufs_hba *hba);
> >> int (*phy_initialization)(struct ufs_hba *);
> >> - int (*device_reset)(struct ufs_hba *hba);
> >> + int (*toggle_device_reset)(struct ufs_hba *hba, bool down);
> >> void (*config_scaling_param)(struct ufs_hba *hba,
> >> struct devfreq_dev_profile *profile,
> >> void *data);
> >> @@ -1216,10 +1216,10 @@ static inline void
> >> ufshcd_vops_dbg_register_dump(struct ufs_hba *hba)
> >> hba->vops->dbg_register_dump(hba);
> >> }
> >>
> >> -static inline int ufshcd_vops_device_reset(struct ufs_hba *hba)
> >> +static inline int ufshcd_vops_toggle_device_reset(struct ufs_hba
> >> *hba,
> >> +bool down)
> >> {
> >> - if (hba->vops && hba->vops->device_reset)
> >> - return hba->vops->device_reset(hba);
> >> + if (hba->vops && hba->vops->toggle_device_reset)
> >> + return hba->vops->toggle_device_reset(hba, down);
> >>
> >> return -EOPNOTSUPP;
> >> }
> >> --
> >> The Qualcomm Innovation Center, Inc. is a member of the Code Aurora
> >> Forum, a Linux Foundation Collaborative Project
On 2020-12-22 14:00, Kiwoong Kim wrote:
>> On 2020-12-22 10:04, Kiwoong Kim wrote:
>> >> As per specs, e.g, JESD220E chapter 7.2, while powering off/on the
>> >> ufs device, RST_N signal and REF_CLK signal should be between
>> >> VSS(Ground) and VCCQ/VCCQ2.
>> >>
>> >> To flexibly control device reset line, re-name the function
>> >> ufschd_vops_device_reset(sturct ufs_hba *hba) to ufshcd_
>> >> vops_toggle_device_reset(sturct ufs_hba *hba, bool down). The new
>> >> parameter "bool down" is used to separate device reset line pulling
>> >> down from pulling up.
>> >>
>> >> Cc: Kiwoong Kim <[email protected]>
>> >> Cc: Stanley Chu <[email protected]>
>> >> Signed-off-by: Ziqi Chen <[email protected]>
>> >> ---
>> >> drivers/scsi/ufs/ufs-mediatek.c | 27 +++++++++-----------------
>> >> drivers/scsi/ufs/ufs-qcom.c | 22 ++++++++++-----------
>> >> drivers/scsi/ufs/ufshcd.c | 43
>> >> ++++++++++++++++++++++++++++++------
>> > --
>> >> ---
>> >> drivers/scsi/ufs/ufshcd.h | 10 +++++-----
>> >> 4 files changed, 56 insertions(+), 46 deletions(-)
>> >>
>> >> diff --git a/drivers/scsi/ufs/ufs-mediatek.c b/drivers/scsi/ufs/ufs-
>> >> mediatek.c index 80618af..bff2c42 100644
>> >> --- a/drivers/scsi/ufs/ufs-mediatek.c
>> >> +++ b/drivers/scsi/ufs/ufs-mediatek.c
>> >> @@ -841,27 +841,18 @@ static int ufs_mtk_link_startup_notify(struct
>> >> ufs_hba *hba,
>> >> return ret;
>> >> }
>> >>
>> >> -static int ufs_mtk_device_reset(struct ufs_hba *hba)
>> >> +static int ufs_mtk_toggle_device_reset(struct ufs_hba *hba, bool
>> >> down)
>> >> {
>> >> struct arm_smccc_res res;
>> >>
>> >> - ufs_mtk_device_reset_ctrl(0, res);
>> >> -
>> >> - /*
>> >> - * The reset signal is active low. UFS devices shall detect
>> >> - * more than or equal to 1us of positive or negative RST_n
>> >> - * pulse width.
>> >> - *
>> >> - * To be on safe side, keep the reset low for at least 10us.
>> >> - */
>> >> - usleep_range(10, 15);
>> >> -
>> >> - ufs_mtk_device_reset_ctrl(1, res);
>> >> -
>> >> - /* Some devices may need time to respond to rst_n */
>> >> - usleep_range(10000, 15000);
>> >> + if (down) {
>> >> + ufs_mtk_device_reset_ctrl(0, res);
>> >> + } else {
>> >> + ufs_mtk_device_reset_ctrl(1, res);
>> >>
>> >> - dev_info(hba->dev, "device reset done\n");
>> >> + /* Some devices may need time to respond to rst_n */
>> >> + usleep_range(10000, 15000);
>> >> + }
>> >>
>> >> return 0;
>> >> }
>> >> @@ -1052,7 +1043,7 @@ static const struct ufs_hba_variant_ops
>> >> ufs_hba_mtk_vops = {
>> >> .suspend = ufs_mtk_suspend,
>> >> .resume = ufs_mtk_resume,
>> >> .dbg_register_dump = ufs_mtk_dbg_register_dump,
>> >> - .device_reset = ufs_mtk_device_reset,
>> >> + .toggle_device_reset = ufs_mtk_toggle_device_reset,
>> >> .event_notify = ufs_mtk_event_notify,
>> >> };
>> >>
>> >> diff --git a/drivers/scsi/ufs/ufs-qcom.c
>> >> b/drivers/scsi/ufs/ufs-qcom.c index 2206b1e..c2ccaa5 100644
>> >> --- a/drivers/scsi/ufs/ufs-qcom.c
>> >> +++ b/drivers/scsi/ufs/ufs-qcom.c
>> >> @@ -1404,12 +1404,13 @@ static void ufs_qcom_dump_dbg_regs(struct
>> >> ufs_hba
>> >> *hba) }
>> >>
>> >> /**
>> >> - * ufs_qcom_device_reset() - toggle the (optional) device reset line
>> >> + * ufs_qcom_toggle_device_reset() - toggle the (optional) device
>> >> reset
>> >> + line
>> >> * @hba: per-adapter instance
>> >> + * @down: pull down or pull up device reset line
>> >> *
>> >> * Toggles the (optional) reset line to reset the attached device.
>> >> */
>> >> -static int ufs_qcom_device_reset(struct ufs_hba *hba)
>> >> +static int ufs_qcom_toggle_device_reset(struct ufs_hba *hba, bool
>> >> down)
>> >> {
>> >> struct ufs_qcom_host *host = ufshcd_get_variant(hba);
>> >>
>> >> @@ -1417,15 +1418,12 @@ static int ufs_qcom_device_reset(struct
>> >> ufs_hba
>> >> *hba)
>> >> if (!host->device_reset)
>> >> return -EOPNOTSUPP;
>> >>
>> >> - /*
>> >> - * The UFS device shall detect reset pulses of 1us, sleep for 10us
>> >> to
>> >> - * be on the safe side.
>> >> - */
>> >> - gpiod_set_value_cansleep(host->device_reset, 1);
>> >> - usleep_range(10, 15);
>> >> -
>> >> - gpiod_set_value_cansleep(host->device_reset, 0);
>> >> - usleep_range(10, 15);
>> >> + if (down) {
>> >> + gpiod_set_value_cansleep(host->device_reset, 1);
>> >> + } else {
>> >> + gpiod_set_value_cansleep(host->device_reset, 0);
>> >> + usleep_range(10, 15);
>> >> + }
>> >>
>> >> return 0;
>> >> }
>> >> @@ -1473,7 +1471,7 @@ static const struct ufs_hba_variant_ops
>> >> ufs_hba_qcom_vops = {
>> >> .suspend = ufs_qcom_suspend,
>> >> .resume = ufs_qcom_resume,
>> >> .dbg_register_dump = ufs_qcom_dump_dbg_regs,
>> >> - .device_reset = ufs_qcom_device_reset,
>> >> + .toggle_device_reset = ufs_qcom_toggle_device_reset,
>> >> .config_scaling_param = ufs_qcom_config_scaling_param,
>> >> .program_key = ufs_qcom_ice_program_key,
>> >> };
>> >> diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
>> >> index e221add..2ee905f 100644
>> >> --- a/drivers/scsi/ufs/ufshcd.c
>> >> +++ b/drivers/scsi/ufs/ufshcd.c
>> >> @@ -585,7 +585,20 @@ static void ufshcd_device_reset(struct ufs_hba
>> >> *hba)
>> >> {
>> >> int err;
>> >>
>> >> - err = ufshcd_vops_device_reset(hba);
>> >> + err = ufshcd_vops_toggle_device_reset(hba, true);
>> >> + if (err) {
>> >> + dev_err(hba->dev, "device reset pulling down failure: %d\n",
>> >> err);
>> >> + return;
>> >> + }
>> >> +
>> >> + /*
>> >> + * The reset signal is active low. The UFS device
>> >> + * shall detect reset pulses of 1us, sleep for at
>> >> + * least 10us to be on the safe side.
>> >> + */
>> >> + usleep_range(10, 15);
>> >
>> > Is there any point where UFS specification tells this explicitly?
>> > I think this should be moved only if the number, i.e. 10 and 15 just
>> > relies on hardware conditions.
>> >
>> >
>> > Thanks.
>> > Kiwoong Kim
>>
>> Hi Kiwoong,
>>
>> Thanks for your comment. JESD220E Line 610~611 "The UFS device shall
>> detect more than or equal to 1us of positive or negative RST_n pulse".
>> Both QCOM and Mediatek use 10~15us. What number do you think more
>> appropriate?
>>
>> Best Regards,
>> Ziqi
>
> With yours, all the SoC vendors should wait for around 10us
> unconditionally
> even if there will be a possibility that some can use shorter period.
> I see this as a sort of optimization point.
>
>
> Thanks.
> Kiwoong Kim
Got your point. As it is a controversial delay among different SoC
vendor, I'll
move it back to vops and handle it by vendor's driver.
Best Regards,
Ziqi
>>
>> >
>> >> + err = ufshcd_vops_toggle_device_reset(hba, false);
>> >>
>> >> if (!err) {
>> >> ufshcd_set_ufs_dev_active(hba);
>> >> @@ -593,7 +606,11 @@ static void ufshcd_device_reset(struct ufs_hba
>> >> *hba)
>> >> hba->wb_enabled = false;
>> >> hba->wb_buf_flush_enabled = false;
>> >> }
>> >> + dev_info(hba->dev, "device reset done\n");
>> >> + } else {
>> >> + dev_err(hba->dev, "device reset pulling up failure: %d\n",
>> >> err);
>> >> }
>> >> +
>> >> if (err != -EOPNOTSUPP)
>> >> ufshcd_update_evt_hist(hba, UFS_EVT_DEV_RESET, err); } @@ -
>> >> 8686,8 +8703,6 @@ static int ufshcd_suspend(struct ufs_hba *hba, enum
>> >> ufs_pm_op pm_op)
>> >> if (ret)
>> >> goto set_dev_active;
>> >>
>> >> - ufshcd_vreg_set_lpm(hba);
>> >> -
>> >> disable_clks:
>> >> /*
>> >> * Call vendor specific suspend callback. As these callbacks may
>> >> access @@ -8703,6 +8718,9 @@ static int ufshcd_suspend(struct ufs_hba
>> >> *hba, enum ufs_pm_op pm_op)
>> >> */
>> >> ufshcd_disable_irq(hba);
>> >>
>> >> + if (ufshcd_is_link_off(hba))
>> >> + ufshcd_vops_toggle_device_reset(hba, true);
>> >> +
>> >> ufshcd_setup_clocks(hba, false);
>> >>
>> >> if (ufshcd_is_clkgating_allowed(hba)) { @@ -8711,6 +8729,8 @@
>> >> static int ufshcd_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op)
>> >> hba->clk_gating.state);
>> >> }
>> >>
>> >> + ufshcd_vreg_set_lpm(hba);
>> >> +
>> >> /* Put the host controller in low power mode if possible */
>> >> ufshcd_hba_vreg_set_lpm(hba);
>> >> goto out;
>> >> @@ -8778,18 +8798,19 @@ static int ufshcd_resume(struct ufs_hba *hba,
>> >> enum ufs_pm_op pm_op)
>> >> old_link_state = hba->uic_link_state;
>> >>
>> >> ufshcd_hba_vreg_set_hpm(hba);
>> >> +
>> >> + ret = ufshcd_vreg_set_hpm(hba);
>> >> + if (ret)
>> >> + goto out;
>> >> +
>> >> /* Make sure clocks are enabled before accessing controller */
>> >> ret = ufshcd_setup_clocks(hba, true);
>> >> if (ret)
>> >> - goto out;
>> >> + goto disable_vreg;
>> >>
>> >> /* enable the host irq as host controller would be active soon */
>> >> ufshcd_enable_irq(hba);
>> >>
>> >> - ret = ufshcd_vreg_set_hpm(hba);
>> >> - if (ret)
>> >> - goto disable_irq_and_vops_clks;
>> >> -
>> >> /*
>> >> * Call vendor specific resume callback. As these callbacks may
>> >> access
>> >> * vendor specific host controller register space call them when
>> >> the @@ -8797,7 +8818,7 @@ static int ufshcd_resume(struct ufs_hba
>> >> *hba, enum ufs_pm_op pm_op)
>> >> */
>> >> ret = ufshcd_vops_resume(hba, pm_op);
>> >> if (ret)
>> >> - goto disable_vreg;
>> >> + 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)); @@ -8864,8 +8885,6 @@ static int
>> >> ufshcd_resume(struct ufs_hba *hba, enum ufs_pm_op pm_op)
>> >> ufshcd_link_state_transition(hba, old_link_state, 0);
>> >> vendor_suspend:
>> >> ufshcd_vops_suspend(hba, pm_op);
>> >> -disable_vreg:
>> >> - ufshcd_vreg_set_lpm(hba);
>> >> disable_irq_and_vops_clks:
>> >> ufshcd_disable_irq(hba);
>> >> if (hba->clk_scaling.is_allowed)
>> >> @@ -8876,6 +8895,8 @@ static int ufshcd_resume(struct ufs_hba *hba,
>> >> enum ufs_pm_op pm_op)
>> >> trace_ufshcd_clk_gating(dev_name(hba->dev),
>> >> hba->clk_gating.state);
>> >> }
>> >> +disable_vreg:
>> >> + ufshcd_vreg_set_lpm(hba);
>> >> out:
>> >> hba->pm_op_in_progress = 0;
>> >> if (ret)
>> >> diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
>> >> index 9bb5f0e..dccc3eb 100644
>> >> --- a/drivers/scsi/ufs/ufshcd.h
>> >> +++ b/drivers/scsi/ufs/ufshcd.h
>> >> @@ -319,7 +319,7 @@ struct ufs_pwr_mode_info {
>> >> * @resume: called during host controller PM callback
>> >> * @dbg_register_dump: used to dump controller debug information
>> >> * @phy_initialization: used to initialize phys
>> >> - * @device_reset: called to issue a reset pulse on the UFS device
>> >> + * @toggle_device_reset: called to change logic level of reset gpio
>> >> on
>> >> + the UFS device
>> >> * @program_key: program or evict an inline encryption key
>> >> * @event_notify: called to notify important events
>> >> */
>> >> @@ -350,7 +350,7 @@ struct ufs_hba_variant_ops {
>> >> int (*resume)(struct ufs_hba *, enum ufs_pm_op);
>> >> void (*dbg_register_dump)(struct ufs_hba *hba);
>> >> int (*phy_initialization)(struct ufs_hba *);
>> >> - int (*device_reset)(struct ufs_hba *hba);
>> >> + int (*toggle_device_reset)(struct ufs_hba *hba, bool down);
>> >> void (*config_scaling_param)(struct ufs_hba *hba,
>> >> struct devfreq_dev_profile *profile,
>> >> void *data);
>> >> @@ -1216,10 +1216,10 @@ static inline void
>> >> ufshcd_vops_dbg_register_dump(struct ufs_hba *hba)
>> >> hba->vops->dbg_register_dump(hba);
>> >> }
>> >>
>> >> -static inline int ufshcd_vops_device_reset(struct ufs_hba *hba)
>> >> +static inline int ufshcd_vops_toggle_device_reset(struct ufs_hba
>> >> *hba,
>> >> +bool down)
>> >> {
>> >> - if (hba->vops && hba->vops->device_reset)
>> >> - return hba->vops->device_reset(hba);
>> >> + if (hba->vops && hba->vops->toggle_device_reset)
>> >> + return hba->vops->toggle_device_reset(hba, down);
>> >>
>> >> return -EOPNOTSUPP;
>> >> }
>> >> --
>> >> The Qualcomm Innovation Center, Inc. is a member of the Code Aurora
>> >> Forum, a Linux Foundation Collaborative Project