On Monday, May 06, 2013, Sujit Reddy Thumma 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> > > --- > 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 | 163 ++++++++++++++++++++++++++++++++++++++++++--- > drivers/scsi/ufs/ufshcd.h | 4 + > 2 files changed, 158 insertions(+), 9 deletions(-) > > diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c > index 3607ffb..4090f6c 100644 > --- a/drivers/scsi/ufs/ufshcd.c > +++ b/drivers/scsi/ufs/ufshcd.c > @@ -34,6 +34,7 @@ > */ > > #include <linux/async.h> > +#include <linux/iopoll.h> linux/iopoll.h: No such file or directory Please check. > > #include "ufshcd.h" > > @@ -44,6 +45,13 @@ > /* 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, > @@ -630,7 +638,7 @@ 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 +655,8 @@ 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 +745,18 @@ 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 +771,13 @@ 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 +826,7 @@ 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 +1286,103 @@ 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)); > + > + if (timeout) { > + spin_lock_irqsave(hba->host->host_lock, flags); > + err = ufshcd_get_tr_ocs(lrbp); > + spin_unlock_irqrestore(hba->host->host_lock, flags); > + } else { > + err = -ETIMEDOUT; > + } > + > + 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; > + > + /* 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 */ > + if (readl_poll_timeout( > + hba->mmio_base + REG_UTP_TRANSFER_REQ_DOOR_BELL, > + reg, !(reg & (1 << INTERNAL_CMD_TAG)), > + 1000, 1000)) > + retries = 0; Also, readl_poll_timeout function is not present in Linux kernel. Could you check your kernel? You should implement this part in other way. Additionally, is there no need to clear 'lrbp->completion'? It will have invalid value after current function is out. Thanks, Seungwon Jeon > + } > + > + 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 +1856,16 @@ 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 +1877,7 @@ 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 +1885,20 @@ 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])) { > + 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 +1906,8 @@ 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 +2205,16 @@ 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; > }; > > /** > -- > QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member > of Code Aurora Forum, hosted by The Linux Foundation. > > -- > To unsubscribe from this list: send the line "unsubscribe linux-scsi" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-arm-msm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html