Re: [PATCH v3 03/10] ufs: host: Add common Hibern8 TX FSM polling helper

[Larisa Ileana Grigore <larisa.grigore@oss.nxp.com>]

On 9/16/2026 7:22 PM, Frank Li wrote:
> On Wed, Sep 16, 2026 at 10:44:04AM +0200, Larisa Grigore wrote:
>> Factor out the common logic used to poll TX_FSM_STATE until the TX lanes
>> enter Hibern8 into ufshcd_check_hibern8().
>>
>> The HiSilicon and Qualcomm drivers currently implement similar checks
>> using the UniPro TX_FSM_STATE attribute after link/PHY bring-up. Move
>> this logic to a common helper in ufshcd so it can be shared across host
>> controller drivers.
>>
>> Switch the HiSilicon and Qualcomm drivers to use the new helper and drop
>> their local implementations. While at it, normalize the "TX lane failed to
>> reach Hibern8" error path to return -ETIMEDOUT instead of the raw
>> TX_FSM_STATE value (qcom) or -1 (hisi), so all callers get a proper errno.
>> This is an intentional, harmless change of the returned error value; the
>> pass/fail behaviour at the call sites is unchanged.
>>
>> Unlike the initial implementation, the timeout error is now reported only
>> once by ufshcd_dme_check_tx_hibern8() after its final check, instead of
>> per lane.
>>
>> This also prepares for reusing the same UniPro-specific Hibern8 check in
>> a subsequent commit.
>>
>> Signed-off-by: Larisa Grigore <larisa.grigore@oss.nxp.com>
>> ---
>>   drivers/ufs/core/ufshcd.c   | 86 +++++++++++++++++++++++++++++++++++++
>>   drivers/ufs/host/ufs-hisi.c | 48 +--------------------
>>   drivers/ufs/host/ufs-qcom.c | 42 +-----------------
>>   include/ufs/ufshcd.h        |  3 ++
>>   4 files changed, 91 insertions(+), 88 deletions(-)
>>
>> diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c
>> index 2ba244cf40ac..f34b7fe54a16 100644
>> --- a/drivers/ufs/core/ufshcd.c
>> +++ b/drivers/ufs/core/ufshcd.c
>> @@ -4448,6 +4448,92 @@ int ufshcd_dme_get_attr(struct ufs_hba *hba, u32 attr_sel,
>>   }
>>   EXPORT_SYMBOL_GPL(ufshcd_dme_get_attr);
>>
>> +/**
>> + * ufshcd_poll_tx_hibern8_lanes - Check TX_FSM_STATE of all TX lanes once
>> + * @hba: host controller instance
>> + * @num_lanes: number of TX lanes to check
>> + *
>> + * Read TX_FSM_STATE for every lane and verify it reached Hibern8.
>> + *
>> + * Return: 0 if all lanes are in Hibern8, -EAGAIN if any lane is not (yet)
>> + * in Hibern8, or a negative errno (e.g. -ETIMEDOUT from a hard UIC command
>> + * timeout) if the attribute read fails.
>> + */
>> +static int ufshcd_poll_tx_hibern8_lanes(struct ufs_hba *hba,
>> +					unsigned int num_lanes)
>> +{
>> +	u32 tx_fsm_val = 0;
>> +	unsigned int i;
>> +	int err;
>> +
>> +	for (i = 0; i < num_lanes; i++) {
>> +		err = ufshcd_dme_get(hba,
>> +				UIC_ARG_MIB_SEL(TX_FSM_STATE,
>> +					UIC_ARG_MPHY_TX_GEN_SEL_INDEX(i)),
>> +				&tx_fsm_val);
>> +		if (err) {
>> +			dev_err(hba->dev,
>> +				"%s: unable to get TX_FSM_STATE for lane %u, err %d\n",
>> +				__func__, i, err);
>> +			return err;
>> +		}
>> +
>> +		if (tx_fsm_val != TX_STATE_HIBERN8)
>> +			return -EAGAIN;
>> +	}
>> +
>> +	return 0;
>> +}
>> +
>> +/**
>> + * ufshcd_dme_check_tx_hibern8 - Check if all TX lanes entered Hibern8 state
>> + * @hba: host controller instance
>> + * @num_lanes: number of TX lanes to check
>> + * @timeout_ms: timeout in milliseconds for all lanes
>> + *
>> + * Return: 0 on success, negative errno on failure.
>> + */
>> +int ufshcd_dme_check_tx_hibern8(struct ufs_hba *hba, unsigned int num_lanes,
>> +				unsigned int timeout_ms)
>> +{
>> +	unsigned long timeout;
>> +	int err;
>> +
>> +	if (!num_lanes)
>> +		return -EINVAL;
>> +
>> +	timeout = jiffies + msecs_to_jiffies(timeout_ms);
>> +
>> +	do {
>> +		err = ufshcd_poll_tx_hibern8_lanes(hba, num_lanes);
>> +		/*
>> +		 * -EAGAIN means the lanes are simply not in HIBERN8 yet, so
>> +		 * keep polling. Any other error is a real failure and must
>> +		 * be returned immediately instead of being retried.
>> +		 */
>> +		if (err != -EAGAIN)
>> +			return err;
>> +
>> +		/* sleep for max. 200us */
>> +		usleep_range(100, 200);
>> +	} while (time_before(jiffies, timeout));
>> +
>> +	/*
>> +	 * We might have been scheduled out for long during polling, so do
>> +	 * one final check before reporting timeout.
>> +	 */
>> +	err = ufshcd_poll_tx_hibern8_lanes(hba, num_lanes);
>> +	if (err == -EAGAIN) {
>> +		dev_err(hba->dev,
>> +			"%s: timeout waiting for TX lanes to enter HIBERN8\n",
>> +			__func__);
>> +		err = -ETIMEDOUT;
>> +	}
> 
> 
> why not use read read_poll_timeout()
> 
> read_poll_timeout(ufshcd_poll_tx_hibern8_lanes, err, err != -EAGAIN, timeout_ms,
> 		  0, hba, numlanes);
> 
> 
> Frank
> 
Thank you for the suggestion!

Best regards,
Larisa

>> +
>> +	return err;
>> +}
>> +EXPORT_SYMBOL_GPL(ufshcd_dme_check_tx_hibern8);
>> +
>>   /**
>>    * ufshcd_dme_rmw - get modify set a DME attribute
>>    * @hba: per adapter instance
>> diff --git a/drivers/ufs/host/ufs-hisi.c b/drivers/ufs/host/ufs-hisi.c
>> index bd223bda1ce2..b84075dfe00d 100644
>> --- a/drivers/ufs/host/ufs-hisi.c
>> +++ b/drivers/ufs/host/ufs-hisi.c
>> @@ -22,50 +22,6 @@
>>   #include <ufs/ufshci.h>
>>   #include <ufs/ufs_quirks.h>
>>
>> -static int ufs_hisi_check_hibern8(struct ufs_hba *hba)
>> -{
>> -	int err = 0;
>> -	u32 tx_fsm_val_0 = 0;
>> -	u32 tx_fsm_val_1 = 0;
>> -	unsigned long timeout = jiffies + msecs_to_jiffies(HBRN8_POLL_TOUT_MS);
>> -
>> -	do {
>> -		err = ufshcd_dme_get(hba, UIC_ARG_MIB_SEL(TX_FSM_STATE, 0),
>> -				      &tx_fsm_val_0);
>> -		err |= ufshcd_dme_get(hba,
>> -		    UIC_ARG_MIB_SEL(TX_FSM_STATE, 1), &tx_fsm_val_1);
>> -		if (err || (tx_fsm_val_0 == TX_STATE_HIBERN8 &&
>> -			tx_fsm_val_1 == TX_STATE_HIBERN8))
>> -			break;
>> -
>> -		/* sleep for max. 200us */
>> -		usleep_range(100, 200);
>> -	} while (time_before(jiffies, timeout));
>> -
>> -	/*
>> -	 * we might have scheduled out for long during polling so
>> -	 * check the state again.
>> -	 */
>> -	if (time_after(jiffies, timeout)) {
>> -		err = ufshcd_dme_get(hba, UIC_ARG_MIB_SEL(TX_FSM_STATE, 0),
>> -				     &tx_fsm_val_0);
>> -		err |= ufshcd_dme_get(hba,
>> -		 UIC_ARG_MIB_SEL(TX_FSM_STATE, 1), &tx_fsm_val_1);
>> -	}
>> -
>> -	if (err) {
>> -		dev_err(hba->dev, "%s: unable to get TX_FSM_STATE, err %d\n",
>> -			__func__, err);
>> -	} else if (tx_fsm_val_0 != TX_STATE_HIBERN8 ||
>> -			 tx_fsm_val_1 != TX_STATE_HIBERN8) {
>> -		err = -1;
>> -		dev_err(hba->dev, "%s: invalid TX_FSM_STATE, lane0 = %d, lane1 = %d\n",
>> -			__func__, tx_fsm_val_0, tx_fsm_val_1);
>> -	}
>> -
>> -	return err;
>> -}
>> -
>>   static void ufs_hisi_clk_init(struct ufs_hba *hba)
>>   {
>>   	struct ufs_hisi_host *host = ufshcd_get_variant(hba);
>> @@ -224,9 +180,7 @@ static int ufs_hisi_link_startup_pre_change(struct ufs_hba *hba)
>>
>>   	/* Unipro VS_mphy_disable */
>>   	ufshcd_dme_set(hba, UIC_ARG_MIB_SEL(0xD0C1, 0x0), 0x0);
>> -	err = ufs_hisi_check_hibern8(hba);
>> -	if (err)
>> -		dev_err(hba->dev, "ufs_hisi_check_hibern8 error\n");
>> +	err = ufshcd_dme_check_tx_hibern8(hba, 2, HBRN8_POLL_TOUT_MS);
>>
>>   	if (!(host->caps & UFS_HISI_CAP_PHY10nm))
>>   		ufshcd_writel(hba, UFS_HCLKDIV_NORMAL_VALUE, UFS_REG_HCLKDIV);
>> diff --git a/drivers/ufs/host/ufs-qcom.c b/drivers/ufs/host/ufs-qcom.c
>> index 1e492dac8d93..815ca82a0878 100644
>> --- a/drivers/ufs/host/ufs-qcom.c
>> +++ b/drivers/ufs/host/ufs-qcom.c
>> @@ -382,46 +382,6 @@ static int ufs_qcom_init_lane_clks(struct ufs_qcom_host *host)
>>   	return 0;
>>   }
>>
>> -static int ufs_qcom_check_hibern8(struct ufs_hba *hba)
>> -{
>> -	int err;
>> -	u32 tx_fsm_val;
>> -	unsigned long timeout = jiffies + msecs_to_jiffies(HBRN8_POLL_TOUT_MS);
>> -
>> -	do {
>> -		err = ufshcd_dme_get(hba,
>> -				UIC_ARG_MIB_SEL(TX_FSM_STATE,
>> -					UIC_ARG_MPHY_TX_GEN_SEL_INDEX(0)),
>> -				&tx_fsm_val);
>> -		if (err || tx_fsm_val == TX_STATE_HIBERN8)
>> -			break;
>> -
>> -		/* sleep for max. 200us */
>> -		usleep_range(100, 200);
>> -	} while (time_before(jiffies, timeout));
>> -
>> -	/*
>> -	 * we might have scheduled out for long during polling so
>> -	 * check the state again.
>> -	 */
>> -	if (time_after(jiffies, timeout))
>> -		err = ufshcd_dme_get(hba,
>> -				UIC_ARG_MIB_SEL(TX_FSM_STATE,
>> -					UIC_ARG_MPHY_TX_GEN_SEL_INDEX(0)),
>> -				&tx_fsm_val);
>> -
>> -	if (err) {
>> -		dev_err(hba->dev, "%s: unable to get TX_FSM_STATE, err %d\n",
>> -				__func__, err);
>> -	} else if (tx_fsm_val != TX_STATE_HIBERN8) {
>> -		err = tx_fsm_val;
>> -		dev_err(hba->dev, "%s: invalid TX_FSM_STATE = %d\n",
>> -				__func__, err);
>> -	}
>> -
>> -	return err;
>> -}
>> -
>>   static void ufs_qcom_select_unipro_mode(struct ufs_qcom_host *host)
>>   {
>>   	ufshcd_rmwl(host->hba, QUNIPRO_SEL, QUNIPRO_SEL, REG_UFS_CFG1);
>> @@ -607,7 +567,7 @@ static int ufs_qcom_hce_enable_notify(struct ufs_hba *hba,
>>   		break;
>>   	case POST_CHANGE:
>>   		/* check if UFS PHY moved from DISABLED to HIBERN8 */
>> -		err = ufs_qcom_check_hibern8(hba);
>> +		err = ufshcd_dme_check_tx_hibern8(hba, 1, HBRN8_POLL_TOUT_MS);
>>   		ufs_qcom_enable_hw_clk_gating(hba);
>>   		ufs_qcom_ice_enable(host);
>>   		ufs_qcom_config_ice_allocator(host);
>> diff --git a/include/ufs/ufshcd.h b/include/ufs/ufshcd.h
>> index dfd302f2dc7c..0d9d0a26eb20 100644
>> --- a/include/ufs/ufshcd.h
>> +++ b/include/ufs/ufshcd.h
>> @@ -1556,6 +1556,9 @@ extern int ufshcd_dme_set_attr(struct ufs_hba *hba, u32 attr_sel,
>>   			       u8 attr_set, u32 mib_val, u8 peer);
>>   extern int ufshcd_dme_get_attr(struct ufs_hba *hba, u32 attr_sel,
>>   			       u32 *mib_val, u8 peer);
>> +extern int ufshcd_dme_check_tx_hibern8(struct ufs_hba *hba,
>> +				       unsigned int num_lanes,
>> +				       unsigned int timeout_ms);
>>   extern int ufshcd_change_power_mode(struct ufs_hba *hba,
>>   				    struct ufs_pa_layer_attr *pwr_mode,
>>   				    enum ufshcd_pmc_policy pmc_policy);
>> --
>> 2.43.0
>>
>>