The UFS host software uses a combination of a host register set,
and Transfer Request Descriptors in system memory to communicate
with host controller hardware. In its mmio space, a separate places
are assigned to UTP Transfer Request Descriptor ("utrd") list, and
to UTP Task Management Request Descriptor ("utmrd") list.
The provided API supports utrd-typed requests: nop out
and device management commands. It also supports utmrd-type
requests: task management requests.
Other UPIU types are not supported for now.
We utilize the already existing code for tag and task work queues.
That is, all utrd-typed UPIUs are "disguised" as device management
commands. Similarly, the utmrd-typed UPUIs uses the task management
infrastructure.
It is up to the caller to fill the upiu request properly,
as it will be copied without any further input validations.
Signed-off-by: Avri Altman <avri.altman@xxxxxxx>
---
drivers/scsi/ufs/ufshcd.c | 151 ++++++++++++++++++++++++++++++++++++++++++++++
drivers/scsi/ufs/ufshcd.h | 6 ++
2 files changed, 157 insertions(+)
diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index e53e145..efde4d82 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -257,6 +257,7 @@ static int __ufshcd_setup_clocks(struct ufs_hba *hba, bool on,
static irqreturn_t ufshcd_intr(int irq, void *__hba);
static int ufshcd_change_power_mode(struct ufs_hba *hba,
struct ufs_pa_layer_attr *pwr_mode);
+
static inline bool ufshcd_valid_tag(struct ufs_hba *hba, int tag)
{
return tag >= 0 && tag < hba->nutrs;
@@ -5663,6 +5664,156 @@ static int ufshcd_issue_tm_cmd(struct ufs_hba *hba,
}
/**
+ * ufshcd_issue_devman_upiu_cmd - API for sending "utrd" type requests
+ * @hba: per-adapter instance
+ * @req_upiu: upiu request
+ * @rsp_upiu: upiu reply
+ * @msgcode: message code, one of UPIU Transaction Codes Initiator to Target
+ * @desc_buff: pointer to descriptor buffer, NULL if NA
+ * @buff_len: descriptor size, 0 if NA
+ * @rw: either READ or WRITE
+ *
+ * Those type of requests uses UTP Transfer Request Descriptor - utrd.
+ * Therefore, it "rides" the device management infrastructure: uses its tag and
+ * tasks work queues.
+ *
+ * Since there is only one available tag for device management commands,
+ * the caller is expected to hold the hba->dev_cmd.lock mutex.
+ */
+static int ufshcd_issue_devman_upiu_cmd(struct ufs_hba *hba,
+ struct utp_upiu_req *req_upiu,
+ struct utp_upiu_req *rsp_upiu,
+ u8 *desc_buff, int *buff_len,
+ int cmd_type, int rw)
+{
+ struct ufshcd_lrb *lrbp;
+ int err = 0;
+ int tag;
+ struct completion wait;
+ unsigned long flags;
+ u32 upiu_flags;
+ u8 *descp;
+
+ down_read(&hba->clk_scaling_lock);
+
+ wait_event(hba->dev_cmd.tag_wq, ufshcd_get_dev_cmd_tag(hba, &tag));
+
+ init_completion(&wait);
+ lrbp = &hba->lrb[tag];
+ WARN_ON(lrbp->cmd);
+
+ lrbp->cmd = NULL;
+ lrbp->sense_bufflen = 0;
+ lrbp->sense_buffer = NULL;
+ lrbp->task_tag = tag;
+ lrbp->lun = 0;
+ lrbp->command_type = hba->ufs_version == UFSHCI_VERSION_10 ||
+ hba->ufs_version == UFSHCI_VERSION_11 ?
+ UTP_CMD_TYPE_DEV_MANAGE :
+ UTP_CMD_TYPE_UFS_STORAGE;
+ lrbp->intr_cmd = true;
+ hba->dev_cmd.type = cmd_type;
+
+ /* update the task tag in the request upiu */
+ req_upiu->header.dword_0 |= cpu_to_be32(tag);
+
+ ufshcd_prepare_req_desc_hdr(lrbp, &upiu_flags, DMA_NONE);
+
+ /* just copy the upiu request as it is */
+ memcpy(lrbp->ucd_req_ptr, req_upiu, GENERAL_UPIU_REQUEST_SIZE);
+
+ if (desc_buff && rw == WRITE) {
+ descp = (u8 *)lrbp->ucd_req_ptr + GENERAL_UPIU_REQUEST_SIZE;
+ memcpy(descp, desc_buff, *buff_len);
+ *buff_len = 0;
+ }
+
+ memset(lrbp->ucd_rsp_ptr, 0, sizeof(struct utp_upiu_rsp));
+
+ hba->dev_cmd.complete = &wait;
+
+ /* Make sure descriptors are ready before ringing the doorbell */
+ wmb();
+ spin_lock_irqsave(hba->host->host_lock, flags);
+ ufshcd_send_command(hba, tag);
+ spin_unlock_irqrestore(hba->host->host_lock, flags);
+
+ /*
+ * ignore the returning value here - ufshcd_check_query_response is
+ * bound to fail since dev_cmd.query and dev_cmd.type were left empty.
+ * read the response directly ignoring all errors.
+ */
+ ufshcd_wait_for_dev_cmd(hba, lrbp, QUERY_REQ_TIMEOUT);
+
+ /* just copy the upiu request as it is */
+ memcpy(rsp_upiu, lrbp->ucd_rsp_ptr, GENERAL_UPIU_REQUEST_SIZE);
+
+ ufshcd_put_dev_cmd_tag(hba, tag);
+ wake_up(&hba->dev_cmd.tag_wq);
+ up_read(&hba->clk_scaling_lock);
+ return err;
+}
+
+/**
+ * ufshcd_exec_raw_upiu_cmd - API function for sending raw upiu commands
+ * @hba: per-adapter instance
+ * @req_upiu: upiu request
+ * @rsp_upiu: upiu reply - only 8 DW as we do not support scsi commands
+ * @msgcode: message code, one of UPIU Transaction Codes Initiator to Target
+ * @desc_buff: pointer to descriptor buffer, NULL if NA
+ * @buff_len: descriptor size, 0 if NA
+ * @rw: either READ or WRITE
+ *
+ * Supports UTP Transfer requests (nop and query), and UTP Task
+ * Management requests.
+ * It is up to the caller to fill the upiu conent properly, as it will
+ * be copied without any further input validations.
+ */
+int ufshcd_exec_raw_upiu_cmd(struct ufs_hba *hba,
+ struct utp_upiu_req *req_upiu,
+ struct utp_upiu_req *rsp_upiu,
+ int msgcode,
+ u8 *desc_buff, int *buff_len, int rw)
+{
+ int err;
+ int cmd_type = DEV_CMD_TYPE_QUERY;
+ u8 resp = 0xF;
+
+ if (desc_buff && rw == READ) {
+ err = -ENOTSUPP;
+ goto out;
+ }
+
+ switch (msgcode) {
+ case UPIU_TRANSACTION_NOP_OUT:
+ cmd_type = DEV_CMD_TYPE_NOP;
+ /* fall through */
+ case UPIU_TRANSACTION_QUERY_REQ:
+ ufshcd_hold(hba, false);
+ mutex_lock(&hba->dev_cmd.lock);
+ err = ufshcd_issue_devman_upiu_cmd(hba, req_upiu, rsp_upiu,
+ desc_buff, buff_len,
+ cmd_type, rw);
+ mutex_unlock(&hba->dev_cmd.lock);
+ ufshcd_release(hba);
+
+ break;
+ case UPIU_TRANSACTION_TASK_REQ:
+ err = ufshcd_issue_tm_cmd(hba, req_upiu, rsp_upiu, 0, 0, 0,
+ &resp);
+
+ break;
+ default:
+ err = -EINVAL;
+
+ break;
+ }
+
+out:
+ return err;
+}
+
+/**
* ufshcd_eh_device_reset_handler - device reset handler registered to
* scsi layer.
* @cmd: SCSI command pointer
diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
index 46ea7c3..01e2a82 100644
--- a/drivers/scsi/ufs/ufshcd.h
+++ b/drivers/scsi/ufs/ufshcd.h
@@ -894,6 +894,12 @@ int ufshcd_map_desc_id_to_length(struct ufs_hba *hba, enum desc_idn desc_id,
u32 ufshcd_get_local_unipro_ver(struct ufs_hba *hba);
+int ufshcd_exec_raw_upiu_cmd(struct ufs_hba *hba,
+ struct utp_upiu_req *req_upiu,
+ struct utp_upiu_req *rsp_upiu,
+ int msgcode,
+ u8 *desc_buff, int *buff_len, int rw);
+
/* Wrapper functions for safely calling variant operations */
static inline const char *ufshcd_get_var_name(struct ufs_hba *hba)
{
--
1.9.1
