On 5/7/2013 2:57 PM, Seungwon Jeon wrote:
> 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?
Ah.. Sorry about that. Just realized that the API and iopoll.h exist
only in codeaurora kernel versions. Thanks for pointing this out.
> 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.
Right. Will clear it accordingly. Thanks.
>
> 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.
>>
--
Regards,
Sujit
--
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
