2020-12-09 07:21:30

by Ziqi Chen

[permalink] [raw]
Subject: [PATCH v1 1/1] scsi: ufs: Fix ufs power down/on specs violation

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.

Power down:
1. Assert RST_N low
2. Turn-off REF_CLK
3. Turn-off VCC
4. Turn-off VCCQ/VCCQ2.
power on:
1. Turn-on VCC
2. Turn-on VCCQ/VCCQ2
3. Turn-On REF_CLK
4. Deassert RST_N high.

Signed-off-by: Ziqi Chen <[email protected]>
---
drivers/scsi/ufs/ufs-qcom.c | 14 ++++++++++----
drivers/scsi/ufs/ufshcd.c | 19 +++++++++----------
drivers/scsi/ufs/ufshcd.h | 4 ++--
3 files changed, 21 insertions(+), 16 deletions(-)

diff --git a/drivers/scsi/ufs/ufs-qcom.c b/drivers/scsi/ufs/ufs-qcom.c
index 1e434cc..5ed3a63d 100644
--- a/drivers/scsi/ufs/ufs-qcom.c
+++ b/drivers/scsi/ufs/ufs-qcom.c
@@ -582,6 +582,9 @@ static int ufs_qcom_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op)
ufs_qcom_disable_lane_clks(host);
phy_power_off(phy);

+ if (hba->vops && hba->vops->device_reset)
+ hba->vops->device_reset(hba, false);
+
} else if (!ufs_qcom_is_link_active(hba)) {
ufs_qcom_disable_lane_clks(host);
}
@@ -1400,10 +1403,11 @@ static void ufs_qcom_dump_dbg_regs(struct ufs_hba *hba)
/**
* ufs_qcom_device_reset() - toggle the (optional) device reset line
* @hba: per-adapter instance
+ * @toggle: need pulling up or not
*
* Toggles the (optional) reset line to reset the attached device.
*/
-static int ufs_qcom_device_reset(struct ufs_hba *hba)
+static int ufs_qcom_device_reset(struct ufs_hba *hba, bool toggle)
{
struct ufs_qcom_host *host = ufshcd_get_variant(hba);

@@ -1416,10 +1420,12 @@ static int ufs_qcom_device_reset(struct ufs_hba *hba)
* 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 (toggle) {
+ usleep_range(10, 15);
+ gpiod_set_value_cansleep(host->device_reset, 0);
+ usleep_range(10, 15);
+ }

return 0;
}
diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 92d433d..5ab1c02 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -8633,8 +8633,6 @@ 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
@@ -8664,6 +8662,7 @@ static int ufshcd_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op)

/* Put the host controller in low power mode if possible */
ufshcd_hba_vreg_set_lpm(hba);
+ ufshcd_vreg_set_lpm(hba);
goto out;

set_link_active:
@@ -8729,18 +8728,18 @@ 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
@@ -8748,7 +8747,7 @@ 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));
@@ -8815,8 +8814,6 @@ 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)
@@ -8827,6 +8824,8 @@ 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 61344c4..47c7dab6 100644
--- a/drivers/scsi/ufs/ufshcd.h
+++ b/drivers/scsi/ufs/ufshcd.h
@@ -323,7 +323,7 @@ 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 (*device_reset)(struct ufs_hba *hba, bool);
void (*config_scaling_param)(struct ufs_hba *hba,
struct devfreq_dev_profile *profile,
void *data);
@@ -1211,7 +1211,7 @@ static inline void ufshcd_vops_dbg_register_dump(struct ufs_hba *hba)
static inline void ufshcd_vops_device_reset(struct ufs_hba *hba)
{
if (hba->vops && hba->vops->device_reset) {
- int err = hba->vops->device_reset(hba);
+ int err = hba->vops->device_reset(hba, true);

if (!err)
ufshcd_set_ufs_dev_active(hba);
--
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project


2020-12-09 07:23:34

by Can Guo

[permalink] [raw]
Subject: Re: [PATCH v1 1/1] scsi: ufs: Fix ufs power down/on specs violation

On 2020-12-09 15:09, 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.
>
> Power down:
> 1. Assert RST_N low
> 2. Turn-off REF_CLK
> 3. Turn-off VCC
> 4. Turn-off VCCQ/VCCQ2.
> power on:
> 1. Turn-on VCC
> 2. Turn-on VCCQ/VCCQ2
> 3. Turn-On REF_CLK
> 4. Deassert RST_N high.
>
> Signed-off-by: Ziqi Chen <[email protected]>
> ---
> drivers/scsi/ufs/ufs-qcom.c | 14 ++++++++++----
> drivers/scsi/ufs/ufshcd.c | 19 +++++++++----------
> drivers/scsi/ufs/ufshcd.h | 4 ++--
> 3 files changed, 21 insertions(+), 16 deletions(-)
>
> diff --git a/drivers/scsi/ufs/ufs-qcom.c b/drivers/scsi/ufs/ufs-qcom.c
> index 1e434cc..5ed3a63d 100644
> --- a/drivers/scsi/ufs/ufs-qcom.c
> +++ b/drivers/scsi/ufs/ufs-qcom.c
> @@ -582,6 +582,9 @@ static int ufs_qcom_suspend(struct ufs_hba *hba,
> enum ufs_pm_op pm_op)
> ufs_qcom_disable_lane_clks(host);
> phy_power_off(phy);
>
> + if (hba->vops && hba->vops->device_reset)
> + hba->vops->device_reset(hba, false);
> +

Can you make a new wrapper func to do this? ufs-qcom.c is the vendor
driver, why call hba->vops->func() in vendor driver?

> } else if (!ufs_qcom_is_link_active(hba)) {
> ufs_qcom_disable_lane_clks(host);
> }
> @@ -1400,10 +1403,11 @@ static void ufs_qcom_dump_dbg_regs(struct
> ufs_hba *hba)
> /**
> * ufs_qcom_device_reset() - toggle the (optional) device reset line
> * @hba: per-adapter instance
> + * @toggle: need pulling up or not
> *
> * Toggles the (optional) reset line to reset the attached device.
> */
> -static int ufs_qcom_device_reset(struct ufs_hba *hba)
> +static int ufs_qcom_device_reset(struct ufs_hba *hba, bool toggle)
> {
> struct ufs_qcom_host *host = ufshcd_get_variant(hba);
>
> @@ -1416,10 +1420,12 @@ static int ufs_qcom_device_reset(struct ufs_hba
> *hba)
> * 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 (toggle) {
> + usleep_range(10, 15);
> + gpiod_set_value_cansleep(host->device_reset, 0);
> + usleep_range(10, 15);
> + }
>
> return 0;
> }
> diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
> index 92d433d..5ab1c02 100644
> --- a/drivers/scsi/ufs/ufshcd.c
> +++ b/drivers/scsi/ufs/ufshcd.c
> @@ -8633,8 +8633,6 @@ 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
> @@ -8664,6 +8662,7 @@ static int ufshcd_suspend(struct ufs_hba *hba,
> enum ufs_pm_op pm_op)
>
> /* Put the host controller in low power mode if possible */
> ufshcd_hba_vreg_set_lpm(hba);
> + ufshcd_vreg_set_lpm(hba);
> goto out;
>
> set_link_active:
> @@ -8729,18 +8728,18 @@ 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
> @@ -8748,7 +8747,7 @@ 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));
> @@ -8815,8 +8814,6 @@ 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)
> @@ -8827,6 +8824,8 @@ 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 61344c4..47c7dab6 100644
> --- a/drivers/scsi/ufs/ufshcd.h
> +++ b/drivers/scsi/ufs/ufshcd.h
> @@ -323,7 +323,7 @@ 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 (*device_reset)(struct ufs_hba *hba, bool);
> void (*config_scaling_param)(struct ufs_hba *hba,
> struct devfreq_dev_profile *profile,
> void *data);
> @@ -1211,7 +1211,7 @@ static inline void
> ufshcd_vops_dbg_register_dump(struct ufs_hba *hba)
> static inline void ufshcd_vops_device_reset(struct ufs_hba *hba)
> {
> if (hba->vops && hba->vops->device_reset) {
> - int err = hba->vops->device_reset(hba);
> + int err = hba->vops->device_reset(hba, true);
>
> if (!err)
> ufshcd_set_ufs_dev_active(hba);

2020-12-09 07:50:14

by Ziqi Chen

[permalink] [raw]
Subject: Re: [PATCH v1 1/1] scsi: ufs: Fix ufs power down/on specs violation


Hi Can,

On 2020-12-09 15:27, Can Guo wrote:
> On 2020-12-09 15:09, 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.
>>
>> Power down:
>> 1. Assert RST_N low
>> 2. Turn-off REF_CLK
>> 3. Turn-off VCC
>> 4. Turn-off VCCQ/VCCQ2.
>> power on:
>> 1. Turn-on VCC
>> 2. Turn-on VCCQ/VCCQ2
>> 3. Turn-On REF_CLK
>> 4. Deassert RST_N high.
>>
>> Signed-off-by: Ziqi Chen <[email protected]>
>> ---
>> drivers/scsi/ufs/ufs-qcom.c | 14 ++++++++++----
>> drivers/scsi/ufs/ufshcd.c | 19 +++++++++----------
>> drivers/scsi/ufs/ufshcd.h | 4 ++--
>> 3 files changed, 21 insertions(+), 16 deletions(-)
>>
>> diff --git a/drivers/scsi/ufs/ufs-qcom.c b/drivers/scsi/ufs/ufs-qcom.c
>> index 1e434cc..5ed3a63d 100644
>> --- a/drivers/scsi/ufs/ufs-qcom.c
>> +++ b/drivers/scsi/ufs/ufs-qcom.c
>> @@ -582,6 +582,9 @@ static int ufs_qcom_suspend(struct ufs_hba *hba,
>> enum ufs_pm_op pm_op)
>> ufs_qcom_disable_lane_clks(host);
>> phy_power_off(phy);
>>
>> + if (hba->vops && hba->vops->device_reset)
>> + hba->vops->device_reset(hba, false);
>> +
>
> Instead of doing the pull-down in ufshcd_vops_suspend(), can we do
> it in ufshcd_suspend()? Since it is a common problem for all soc
> vendors.

Sure, agree, Thanks.

>
>> } else if (!ufs_qcom_is_link_active(hba)) {
>> ufs_qcom_disable_lane_clks(host);
>> }
>> @@ -1400,10 +1403,11 @@ static void ufs_qcom_dump_dbg_regs(struct
>> ufs_hba *hba)
>> /**
>> * ufs_qcom_device_reset() - toggle the (optional) device reset line
>> * @hba: per-adapter instance
>> + * @toggle: need pulling up or not
>> *
>> * Toggles the (optional) reset line to reset the attached device.
>> */
>> -static int ufs_qcom_device_reset(struct ufs_hba *hba)
>> +static int ufs_qcom_device_reset(struct ufs_hba *hba, bool toggle)
>> {
>> struct ufs_qcom_host *host = ufshcd_get_variant(hba);
>>
>> @@ -1416,10 +1420,12 @@ static int ufs_qcom_device_reset(struct
>> ufs_hba *hba)
>> * 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 (toggle) {
>> + usleep_range(10, 15);
>> + gpiod_set_value_cansleep(host->device_reset, 0);
>> + usleep_range(10, 15);
>> + }
>>
>> return 0;
>> }
>> diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
>> index 92d433d..5ab1c02 100644
>> --- a/drivers/scsi/ufs/ufshcd.c
>> +++ b/drivers/scsi/ufs/ufshcd.c
>> @@ -8633,8 +8633,6 @@ 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
>> @@ -8664,6 +8662,7 @@ static int ufshcd_suspend(struct ufs_hba *hba,
>> enum ufs_pm_op pm_op)
>>
>> /* Put the host controller in low power mode if possible */
>> ufshcd_hba_vreg_set_lpm(hba);
>> + ufshcd_vreg_set_lpm(hba);
>
> Can you put ufshcd_vreg_set_lpm() before ufshcd_hba_vreg_set_lpm()?

Sure, thanks.

>
>> goto out;
>>
>> set_link_active:
>> @@ -8729,18 +8728,18 @@ 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
>> @@ -8748,7 +8747,7 @@ 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));
>> @@ -8815,8 +8814,6 @@ 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)
>> @@ -8827,6 +8824,8 @@ 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 61344c4..47c7dab6 100644
>> --- a/drivers/scsi/ufs/ufshcd.h
>> +++ b/drivers/scsi/ufs/ufshcd.h
>> @@ -323,7 +323,7 @@ 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 (*device_reset)(struct ufs_hba *hba, bool);
>> void (*config_scaling_param)(struct ufs_hba *hba,
>> struct devfreq_dev_profile *profile,
>> void *data);
>> @@ -1211,7 +1211,7 @@ static inline void
>> ufshcd_vops_dbg_register_dump(struct ufs_hba *hba)
>> static inline void ufshcd_vops_device_reset(struct ufs_hba *hba)
>> {
>> if (hba->vops && hba->vops->device_reset) {
>> - int err = hba->vops->device_reset(hba);
>> + int err = hba->vops->device_reset(hba, true);
>>
>> if (!err)
>> ufshcd_set_ufs_dev_active(hba);

2020-12-09 08:06:18

by Can Guo

[permalink] [raw]
Subject: Re: [PATCH v1 1/1] scsi: ufs: Fix ufs power down/on specs violation

On 2020-12-09 15:09, 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.
>
> Power down:
> 1. Assert RST_N low
> 2. Turn-off REF_CLK
> 3. Turn-off VCC
> 4. Turn-off VCCQ/VCCQ2.
> power on:
> 1. Turn-on VCC
> 2. Turn-on VCCQ/VCCQ2
> 3. Turn-On REF_CLK
> 4. Deassert RST_N high.
>
> Signed-off-by: Ziqi Chen <[email protected]>
> ---
> drivers/scsi/ufs/ufs-qcom.c | 14 ++++++++++----
> drivers/scsi/ufs/ufshcd.c | 19 +++++++++----------
> drivers/scsi/ufs/ufshcd.h | 4 ++--
> 3 files changed, 21 insertions(+), 16 deletions(-)
>
> diff --git a/drivers/scsi/ufs/ufs-qcom.c b/drivers/scsi/ufs/ufs-qcom.c
> index 1e434cc..5ed3a63d 100644
> --- a/drivers/scsi/ufs/ufs-qcom.c
> +++ b/drivers/scsi/ufs/ufs-qcom.c
> @@ -582,6 +582,9 @@ static int ufs_qcom_suspend(struct ufs_hba *hba,
> enum ufs_pm_op pm_op)
> ufs_qcom_disable_lane_clks(host);
> phy_power_off(phy);
>
> + if (hba->vops && hba->vops->device_reset)
> + hba->vops->device_reset(hba, false);
> +

Instead of doing the pull-down in ufshcd_vops_suspend(), can we do
it in ufshcd_suspend()? Since it is a common problem for all soc
vendors.

> } else if (!ufs_qcom_is_link_active(hba)) {
> ufs_qcom_disable_lane_clks(host);
> }
> @@ -1400,10 +1403,11 @@ static void ufs_qcom_dump_dbg_regs(struct
> ufs_hba *hba)
> /**
> * ufs_qcom_device_reset() - toggle the (optional) device reset line
> * @hba: per-adapter instance
> + * @toggle: need pulling up or not
> *
> * Toggles the (optional) reset line to reset the attached device.
> */
> -static int ufs_qcom_device_reset(struct ufs_hba *hba)
> +static int ufs_qcom_device_reset(struct ufs_hba *hba, bool toggle)
> {
> struct ufs_qcom_host *host = ufshcd_get_variant(hba);
>
> @@ -1416,10 +1420,12 @@ static int ufs_qcom_device_reset(struct ufs_hba
> *hba)
> * 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 (toggle) {
> + usleep_range(10, 15);
> + gpiod_set_value_cansleep(host->device_reset, 0);
> + usleep_range(10, 15);
> + }
>
> return 0;
> }
> diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
> index 92d433d..5ab1c02 100644
> --- a/drivers/scsi/ufs/ufshcd.c
> +++ b/drivers/scsi/ufs/ufshcd.c
> @@ -8633,8 +8633,6 @@ 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
> @@ -8664,6 +8662,7 @@ static int ufshcd_suspend(struct ufs_hba *hba,
> enum ufs_pm_op pm_op)
>
> /* Put the host controller in low power mode if possible */
> ufshcd_hba_vreg_set_lpm(hba);
> + ufshcd_vreg_set_lpm(hba);

Can you put ufshcd_vreg_set_lpm() before ufshcd_hba_vreg_set_lpm()?

> goto out;
>
> set_link_active:
> @@ -8729,18 +8728,18 @@ 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
> @@ -8748,7 +8747,7 @@ 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));
> @@ -8815,8 +8814,6 @@ 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)
> @@ -8827,6 +8824,8 @@ 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 61344c4..47c7dab6 100644
> --- a/drivers/scsi/ufs/ufshcd.h
> +++ b/drivers/scsi/ufs/ufshcd.h
> @@ -323,7 +323,7 @@ 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 (*device_reset)(struct ufs_hba *hba, bool);
> void (*config_scaling_param)(struct ufs_hba *hba,
> struct devfreq_dev_profile *profile,
> void *data);
> @@ -1211,7 +1211,7 @@ static inline void
> ufshcd_vops_dbg_register_dump(struct ufs_hba *hba)
> static inline void ufshcd_vops_device_reset(struct ufs_hba *hba)
> {
> if (hba->vops && hba->vops->device_reset) {
> - int err = hba->vops->device_reset(hba);
> + int err = hba->vops->device_reset(hba, true);
>
> if (!err)
> ufshcd_set_ufs_dev_active(hba);

2020-12-09 13:59:53

by Can Guo

[permalink] [raw]
Subject: Re: [PATCH v1 1/1] scsi: ufs: Fix ufs power down/on specs violation

On 2020-12-09 15:09, 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.
>
> Power down:
> 1. Assert RST_N low
> 2. Turn-off REF_CLK
> 3. Turn-off VCC
> 4. Turn-off VCCQ/VCCQ2.
> power on:
> 1. Turn-on VCC
> 2. Turn-on VCCQ/VCCQ2
> 3. Turn-On REF_CLK
> 4. Deassert RST_N high.
>
> Signed-off-by: Ziqi Chen <[email protected]>
> ---
> drivers/scsi/ufs/ufs-qcom.c | 14 ++++++++++----
> drivers/scsi/ufs/ufshcd.c | 19 +++++++++----------
> drivers/scsi/ufs/ufshcd.h | 4 ++--
> 3 files changed, 21 insertions(+), 16 deletions(-)
>
> diff --git a/drivers/scsi/ufs/ufs-qcom.c b/drivers/scsi/ufs/ufs-qcom.c
> index 1e434cc..5ed3a63d 100644
> --- a/drivers/scsi/ufs/ufs-qcom.c
> +++ b/drivers/scsi/ufs/ufs-qcom.c
> @@ -582,6 +582,9 @@ static int ufs_qcom_suspend(struct ufs_hba *hba,
> enum ufs_pm_op pm_op)
> ufs_qcom_disable_lane_clks(host);
> phy_power_off(phy);
>
> + if (hba->vops && hba->vops->device_reset)
> + hba->vops->device_reset(hba, false);
> +
> } else if (!ufs_qcom_is_link_active(hba)) {
> ufs_qcom_disable_lane_clks(host);
> }
> @@ -1400,10 +1403,11 @@ static void ufs_qcom_dump_dbg_regs(struct
> ufs_hba *hba)
> /**
> * ufs_qcom_device_reset() - toggle the (optional) device reset line
> * @hba: per-adapter instance
> + * @toggle: need pulling up or not
> *
> * Toggles the (optional) reset line to reset the attached device.
> */
> -static int ufs_qcom_device_reset(struct ufs_hba *hba)
> +static int ufs_qcom_device_reset(struct ufs_hba *hba, bool toggle)
> {
> struct ufs_qcom_host *host = ufshcd_get_variant(hba);
>
> @@ -1416,10 +1420,12 @@ static int ufs_qcom_device_reset(struct ufs_hba
> *hba)
> * 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 (toggle) {
> + usleep_range(10, 15);
> + gpiod_set_value_cansleep(host->device_reset, 0);
> + usleep_range(10, 15);
> + }
>
> return 0;
> }
> diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
> index 92d433d..5ab1c02 100644
> --- a/drivers/scsi/ufs/ufshcd.c
> +++ b/drivers/scsi/ufs/ufshcd.c
> @@ -8633,8 +8633,6 @@ 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
> @@ -8664,6 +8662,7 @@ static int ufshcd_suspend(struct ufs_hba *hba,
> enum ufs_pm_op pm_op)
>
> /* Put the host controller in low power mode if possible */
> ufshcd_hba_vreg_set_lpm(hba);
> + ufshcd_vreg_set_lpm(hba);
> goto out;
>
> set_link_active:
> @@ -8729,18 +8728,18 @@ 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
> @@ -8748,7 +8747,7 @@ 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));
> @@ -8815,8 +8814,6 @@ 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)
> @@ -8827,6 +8824,8 @@ 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 61344c4..47c7dab6 100644
> --- a/drivers/scsi/ufs/ufshcd.h
> +++ b/drivers/scsi/ufs/ufshcd.h
> @@ -323,7 +323,7 @@ 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 (*device_reset)(struct ufs_hba *hba, bool);
> void (*config_scaling_param)(struct ufs_hba *hba,
> struct devfreq_dev_profile *profile,
> void *data);
> @@ -1211,7 +1211,7 @@ static inline void
> ufshcd_vops_dbg_register_dump(struct ufs_hba *hba)
> static inline void ufshcd_vops_device_reset(struct ufs_hba *hba)
> {
> if (hba->vops && hba->vops->device_reset) {
> - int err = hba->vops->device_reset(hba);
> + int err = hba->vops->device_reset(hba, true);
>
> if (!err)
> ufshcd_set_ufs_dev_active(hba);


Please check Stanley's new change
https://lore.kernel.org/patchwork/patch/1350843/.

You may want to re-name the func ufschd_vops_device_reset() to
ufshcd_vops_toggle_device_reset(sturct ufs_hba *hba, bool up) and
similarly re-name device_reset() to toggle_device_reset(hba, up).
Then in the new func ufshcd_device_reset(), call
ufshcd_vops_toggle_device_reset()
twice, once to toggle up, once to toggle down. In this way, you will be
able to use ufshcd_vops_toggle_device_reset() in ufshcd_suspend().

This is just a rough idea.

Thanks,

Can Guo.