On Wed, May 8, 2013 at 3:20 PM, Sujit Reddy Thumma
<sthumma@xxxxxxxxxxxxxx> wrote:
> As part of device initialization sequence, sending NOP OUT UPIU and
> waiting for NOP IN UPIU response is mandatory. This confirms that the
> device UFS Transport (UTP) layer is functional and the host can configure
> the device with further commands. Add support for sending NOP OUT UPIU to
> check the device connection path and test whether the UTP layer on the
> device side is functional during initialization.
>
> Signed-off-by: Sujit Reddy Thumma <sthumma@xxxxxxxxxxxxxx>
>
> ---
> v4:
> - Removed readl_poll_timeout and replaced with wait logic
> - additional checks for completion
> v3:
> - minor bug fix in error path
> v2:
> - fixed INTERNAL_CMD_TAG check in readl_poll_timeout
> - minor cleanup from v1
> - rebased on Seungwon Jeon's UFS V3 patchset
> ---
> drivers/scsi/ufs/ufshcd.c | 197 ++++++++++++++++++++++++++++++++++++++++++--
> drivers/scsi/ufs/ufshcd.h | 4 +
> 2 files changed, 192 insertions(+), 9 deletions(-)
>
> diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
> index 3607ffb..ded770d 100644
> --- a/drivers/scsi/ufs/ufshcd.c
> +++ b/drivers/scsi/ufs/ufshcd.c
> @@ -44,6 +44,13 @@
> /* UIC command timeout, unit: ms */
> #define UIC_CMD_TIMEOUT 500
>
> +/* NOP OUT retries waiting for NOP IN response */
> +#define NOP_OUT_RETRIES 10
> +/* Timeout after 30 msecs if NOP OUT hangs without response */
> +#define NOP_OUT_TIMEOUT 30 /* msecs */
> +/* Reserved tag for internal commands */
> +#define INTERNAL_CMD_TAG 0
> +
> enum {
> UFSHCD_MAX_CHANNEL = 0,
> UFSHCD_MAX_ID = 1,
> @@ -72,6 +79,39 @@ enum {
> INT_AGGR_CONFIG,
> };
>
> +/*
> + * ufshcd_wait_for_register - wait for register value to change
> + * @hba - per-adapter interface
> + * @reg - mmio register offset
> + * @mask - mask to apply to read register value
> + * @val - wait condition
> + * @interval_us - polling interval in microsecs
> + * @timeout_ms - timeout in millisecs
> + *
> + * Returns final register value after iteration
> + */
> +static u32 ufshcd_wait_for_register(struct ufs_hba *hba, u32 reg, u32 mask,
> + u32 val, unsigned long interval_us, unsigned long timeout_ms)
> +{
> + u32 tmp;
> + ktime_t start;
> + unsigned long diff;
> +
> + tmp = ufshcd_readl(hba, reg);
> +
> + start = ktime_get();
> + while ((tmp & mask) == val) {
> + /* wakeup within 50us of expiry */
> + usleep_range(interval_us, interval_us + 50);
> + tmp = ufshcd_readl(hba, reg);
> + diff = ktime_to_ms(ktime_sub(ktime_get(), start));
> + if (diff > timeout_ms)
> + break;
> + }
> +
> + return tmp;
> +}
> +
> /**
> * ufshcd_get_intr_mask - Get the interrupt bit mask
> * @hba - Pointer to adapter instance
> @@ -630,7 +670,7 @@ static void ufshcd_prepare_req_desc(struct ufshcd_lrb *lrbp, u32 *upiu_flags)
> {
> struct utp_transfer_req_desc *req_desc = lrbp->utr_descriptor_ptr;
> enum dma_data_direction cmd_dir =
> - lrbp->cmd->sc_data_direction;
> + lrbp->cmd ? lrbp->cmd->sc_data_direction : DMA_NONE;
> u32 data_direction;
> u32 dword_0;
>
> @@ -647,6 +687,8 @@ static void ufshcd_prepare_req_desc(struct ufshcd_lrb *lrbp, u32 *upiu_flags)
>
> dword_0 = data_direction | (lrbp->command_type
> << UPIU_COMMAND_TYPE_OFFSET);
> + if (lrbp->intr_cmd)
> + dword_0 |= UTP_REQ_DESC_INT_CMD;
>
> /* Transfer request descriptor header fields */
> req_desc->header.dword_0 = cpu_to_le32(dword_0);
> @@ -735,6 +777,18 @@ static void ufshcd_prepare_utp_query_req_upiu(struct ufs_hba *hba,
>
> }
>
> +static inline void ufshcd_prepare_utp_nop_upiu(struct ufshcd_lrb *lrbp)
> +{
> + struct utp_upiu_req *ucd_req_ptr = lrbp->ucd_req_ptr;
> +
> + memset(ucd_req_ptr, 0, sizeof(struct utp_upiu_req));
> +
> + /* command descriptor fields */
> + ucd_req_ptr->header.dword_0 =
> + UPIU_HEADER_DWORD(
> + UPIU_TRANSACTION_NOP_OUT, 0, 0, lrbp->task_tag);
> +}
> +
> /**
> * ufshcd_compose_upiu - form UFS Protocol Information Unit(UPIU)
> * @hba - UFS hba
> @@ -749,11 +803,13 @@ static int ufshcd_compose_upiu(struct ufs_hba *hba, struct ufshcd_lrb *lrbp)
> case UTP_CMD_TYPE_SCSI:
> case UTP_CMD_TYPE_DEV_MANAGE:
> ufshcd_prepare_req_desc(lrbp, &upiu_flags);
> - if (lrbp->command_type == UTP_CMD_TYPE_SCSI)
> + if (lrbp->cmd && lrbp->command_type == UTP_CMD_TYPE_SCSI)
> ufshcd_prepare_utp_scsi_cmd_upiu(lrbp, upiu_flags);
> - else
> + else if (lrbp->cmd && ufshcd_is_query_req(lrbp))
> ufshcd_prepare_utp_query_req_upiu(hba, lrbp,
> upiu_flags);
> + else if (!lrbp->cmd)
> + ufshcd_prepare_utp_nop_upiu(lrbp);
> break;
> case UTP_CMD_TYPE_UFS:
> /* For UFS native command implementation */
> @@ -802,6 +858,7 @@ static int ufshcd_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *cmd)
> lrbp->sense_buffer = cmd->sense_buffer;
> lrbp->task_tag = tag;
> lrbp->lun = cmd->device->lun;
> + lrbp->intr_cmd = false;
>
> if (ufshcd_is_query_req(lrbp))
> lrbp->command_type = UTP_CMD_TYPE_DEV_MANAGE;
> @@ -1261,6 +1318,104 @@ int ufshcd_dme_endpt_reset(struct ufs_hba *hba)
> }
> EXPORT_SYMBOL_GPL(ufshcd_dme_endpt_reset);
>
> +static int
> +ufshcd_compose_nop_out_upiu(struct ufs_hba *hba, struct ufshcd_lrb *lrbp)
> +{
> + lrbp->cmd = NULL;
> + lrbp->sense_bufflen = 0;
> + lrbp->sense_buffer = NULL;
> + lrbp->task_tag = INTERNAL_CMD_TAG;
> + lrbp->lun = 0; /* NOP OUT is not specific to any LUN */
> + lrbp->command_type = UTP_CMD_TYPE_DEV_MANAGE;
> + lrbp->intr_cmd = true; /* No interrupt aggregation */
> +
> + return ufshcd_compose_upiu(hba, lrbp);
> +}
> +
> +static int ufshcd_wait_for_nop_cmd(struct ufs_hba *hba, struct ufshcd_lrb *lrbp)
> +{
> + int err = 0;
> + unsigned long timeout;
> + unsigned long flags;
> +
> + timeout = wait_for_completion_timeout(
> + lrbp->completion, msecs_to_jiffies(NOP_OUT_TIMEOUT));
> +
> + spin_lock_irqsave(hba->host->host_lock, flags);
> + lrbp->completion = NULL;
> + if (timeout)
> + err = ufshcd_get_tr_ocs(lrbp);
> + else
> + err = -ETIMEDOUT;
> + spin_unlock_irqrestore(hba->host->host_lock, flags);
> +
> + return err;
> +}
> +
> +/**
> + * ufshcd_validate_dev_connection() - Check device connection status
> + * @hba: per-adapter instance
> + *
> + * Send NOP OUT UPIU and wait for NOP IN response to check whether the
> + * device Transport Protocol (UTP) layer is ready after a reset.
> + * If the UTP layer at the device side is not initialized, it may
> + * not respond with NOP IN UPIU within timeout of %NOP_OUT_TIMEOUT
> + * and we retry sending NOP OUT for %NOP_OUT_RETRIES iterations.
> + */
> +static int ufshcd_validate_dev_connection(struct ufs_hba *hba)
> +{
> + int err;
> + struct ufshcd_lrb *lrbp;
> + unsigned long flags;
> + struct completion wait;
> + int retries = NOP_OUT_RETRIES;
> +
> +retry:
> + init_completion(&wait);
> +
> + spin_lock_irqsave(hba->host->host_lock, flags);
> + lrbp = &hba->lrb[INTERNAL_CMD_TAG];
> + err = ufshcd_compose_nop_out_upiu(hba, lrbp);
> + if (unlikely(err)) {
> + spin_unlock_irqrestore(hba->host->host_lock, flags);
> + goto out;
> + }
> +
> + lrbp->completion = &wait;
> + ufshcd_send_command(hba, INTERNAL_CMD_TAG);
> + spin_unlock_irqrestore(hba->host->host_lock, flags);
> +
> + err = ufshcd_wait_for_nop_cmd(hba, lrbp);
> +
> + if (err == -ETIMEDOUT) {
> + u32 reg;
> + u32 mask = 1 << INTERNAL_CMD_TAG;
> +
> + /* clear outstanding transaction before retry */
> + spin_lock_irqsave(hba->host->host_lock, flags);
> + ufshcd_utrl_clear(hba, INTERNAL_CMD_TAG);
> + __clear_bit(INTERNAL_CMD_TAG, &hba->outstanding_reqs);
> + spin_unlock_irqrestore(hba->host->host_lock, flags);
> +
> + /* poll for max. 1 sec to clear door bell register by h/w */
> + reg = ufshcd_wait_for_register(hba,
> + REG_UTP_TRANSFER_REQ_DOOR_BELL,
> + mask, mask, 1000, 1000);
> + if ((reg & mask) == mask)
> + retries = 0;
> + }
> +
> + if (err && retries--) {
> + dev_dbg(hba->dev, "%s: error %d retrying\n", __func__, err);
> + goto retry;
> + }
> +
> +out:
> + if (err)
> + dev_err(hba->dev, "%s: NOP OUT failed %d\n", __func__, err);
> + return err;
> +}
> +
> /**
> * ufshcd_make_hba_operational - Make UFS controller operational
> * @hba: per adapter instance
> @@ -1734,6 +1889,16 @@ static void ufshcd_uic_cmd_compl(struct ufs_hba *hba, u32 intr_status)
> complete(&hba->hibern8_done);
> }
>
> +/*
> + * ufshcd_is_nop_out_upiu() - check if the command is NOP OUT UPIU
> + * @lrbp: pointer to logical reference block
> + */
> +static inline bool ufshcd_is_nop_out_upiu(struct ufshcd_lrb *lrbp)
> +{
> + return (be32_to_cpu(lrbp->ucd_req_ptr->header.dword_0) >> 24) ==
> + UPIU_TRANSACTION_NOP_OUT;
> +}
> +
> /**
> * ufshcd_transfer_req_compl - handle SCSI and query command completion
> * @hba: per adapter instance
> @@ -1745,6 +1910,7 @@ static void ufshcd_transfer_req_compl(struct ufs_hba *hba)
> u32 tr_doorbell;
> int result;
> int index;
> + bool int_aggr_reset = true;
>
> lrb = hba->lrb;
> tr_doorbell = ufshcd_readl(hba, REG_UTP_TRANSFER_REQ_DOOR_BELL);
> @@ -1752,17 +1918,21 @@ static void ufshcd_transfer_req_compl(struct ufs_hba *hba)
>
> for (index = 0; index < hba->nutrs; index++) {
> if (test_bit(index, &completed_reqs)) {
> -
> - result = ufshcd_transfer_rsp_status(hba, &lrb[index]);
> -
> if (lrb[index].cmd) {
> + result = ufshcd_transfer_rsp_status(
> + hba, &lrb[index]);
> scsi_dma_unmap(lrb[index].cmd);
> lrb[index].cmd->result = result;
> lrb[index].cmd->scsi_done(lrb[index].cmd);
>
> /* Mark completed command as NULL in LRB */
> lrb[index].cmd = NULL;
> + } else if (ufshcd_is_nop_out_upiu(&lrb[index])) {
> + if (lrb[index].completion)
> + complete(lrb[index].completion);
> }
> + /* Don't reset counters for interrupt cmd */
> + int_aggr_reset = lrb[index].intr_cmd ? false : true;
> } /* end of if */
> } /* end of for */
>
> @@ -1770,7 +1940,8 @@ static void ufshcd_transfer_req_compl(struct ufs_hba *hba)
> hba->outstanding_reqs ^= completed_reqs;
>
> /* Reset interrupt aggregation counters */
> - ufshcd_config_int_aggr(hba, INT_AGGR_RESET);
> + if (int_aggr_reset)
> + ufshcd_config_int_aggr(hba, INT_AGGR_RESET);
> }
>
> /**
> @@ -2068,8 +2239,16 @@ static void ufshcd_async_scan(void *data, async_cookie_t cookie)
> int ret;
>
> ret = ufshcd_link_startup(hba);
> - if (!ret)
> - scsi_scan_host(hba->host);
> + if (ret)
> + goto out;
> +
> + ret = ufshcd_validate_dev_connection(hba);
> + if (ret)
> + goto out;
> +
> + scsi_scan_host(hba->host);
> +out:
> + return;
> }
>
> static struct scsi_host_template ufshcd_driver_template = {
> diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
> index 84f758e..17f4995 100644
> --- a/drivers/scsi/ufs/ufshcd.h
> +++ b/drivers/scsi/ufs/ufshcd.h
> @@ -102,6 +102,8 @@ struct uic_command {
> * @command_type: SCSI, UFS, Query.
> * @task_tag: Task tag of the command
> * @lun: LUN of the command
> + * @intr_cmd: Interrupt command (doesn't participate in interrupt aggregation)
> + * @completion: holds the state of completion (used for internal commands)
> */
> struct ufshcd_lrb {
> struct utp_transfer_req_desc *utr_descriptor_ptr;
> @@ -117,6 +119,8 @@ struct ufshcd_lrb {
> int command_type;
> int task_tag;
> unsigned int lun;
> + bool intr_cmd;
> + struct completion *completion;
> };
>
> /**
Please re-base it on Seungwon's V4 patch series and you can add my
Acked-by: Santosh Y <santoshsy@xxxxxxxxx>
--
~Santosh
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