[PATCH v2 13/14] cxlflash: Migrate IOARRIN specific routines to function pointers

[Uma Krishnan]

From: "Matthew R. Ochs" <mro...@linux.vnet.ibm.com>

As staging for supporting hardware with a different queuing mechanism,
move the send_cmd() and context_reset() routines to function pointers
that are configured when the AFU is initialized. In addition, rename
the existing routines to better reflect the queue model they support.

Signed-off-by: Matthew R. Ochs <mro...@linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/common.h |  3 +++
 drivers/scsi/cxlflash/main.c   | 21 +++++++++++----------
 2 files changed, 14 insertions(+), 10 deletions(-)

diff --git a/drivers/scsi/cxlflash/common.h b/drivers/scsi/cxlflash/common.h
index bed8e60..6b8d1d3 100644
--- a/drivers/scsi/cxlflash/common.h
+++ b/drivers/scsi/cxlflash/common.h
@@ -161,6 +161,9 @@ struct afu {
         * fields after this point
         */
 
+       int (*send_cmd)(struct afu *, struct afu_cmd *);
+       void (*context_reset)(struct afu_cmd *);
+
        /* AFU HW */
        struct cxl_ioctl_start_work work;
        struct cxlflash_afu_map __iomem *afu_map;       /* entire MMIO map */
diff --git a/drivers/scsi/cxlflash/main.c b/drivers/scsi/cxlflash/main.c
index 4e70c9a..d2d2d83 100644
--- a/drivers/scsi/cxlflash/main.c
+++ b/drivers/scsi/cxlflash/main.c
@@ -188,12 +188,10 @@ static void cmd_complete(struct afu_cmd *cmd)
 }
 
 /**
- * context_reset() - timeout handler for AFU commands
+ * context_reset_ioarrin() - reset command owner context via IOARRIN register
  * @cmd:       AFU command that timed out.
- *
- * Sends a reset to the AFU.
  */
-static void context_reset(struct afu_cmd *cmd)
+static void context_reset_ioarrin(struct afu_cmd *cmd)
 {
        int nretry = 0;
        u64 rrin = 0x1;
@@ -217,14 +215,14 @@ static void context_reset(struct afu_cmd *cmd)
 }
 
 /**
- * send_cmd() - sends an AFU command
+ * send_cmd_ioarrin() - sends an AFU command via IOARRIN register
  * @afu:       AFU associated with the host.
  * @cmd:       AFU command to send.
  *
  * Return:
  *     0 on success, SCSI_MLQUEUE_HOST_BUSY on failure
  */
-static int send_cmd(struct afu *afu, struct afu_cmd *cmd)
+static int send_cmd_ioarrin(struct afu *afu, struct afu_cmd *cmd)
 {
        struct cxlflash_cfg *cfg = afu->parent;
        struct device *dev = &cfg->dev->dev;
@@ -273,7 +271,7 @@ static int wait_resp(struct afu *afu, struct afu_cmd *cmd)
 
        timeout = wait_for_completion_timeout(&cmd->cevent, timeout);
        if (!timeout) {
-               context_reset(cmd);
+               afu->context_reset(cmd);
                rc = -1;
        }
 
@@ -330,7 +328,7 @@ static int send_tmf(struct afu *afu, struct scsi_cmnd *scp, 
u64 tmfcmd)
                              SISL_REQ_FLAGS_TMF_CMD);
        memcpy(cmd->rcb.cdb, &tmfcmd, sizeof(tmfcmd));
 
-       rc = send_cmd(afu, cmd);
+       rc = afu->send_cmd(afu, cmd);
        if (unlikely(rc)) {
                spin_lock_irqsave(&cfg->tmf_slock, lock_flags);
                cfg->tmf_active = false;
@@ -461,7 +459,7 @@ static int cxlflash_queuecommand(struct Scsi_Host *host, 
struct scsi_cmnd *scp)
        cmd->rcb.req_flags = req_flags;
        memcpy(cmd->rcb.cdb, scp->cmnd, sizeof(cmd->rcb.cdb));
 
-       rc = send_cmd(afu, cmd);
+       rc = afu->send_cmd(afu, cmd);
        if (unlikely(rc))
                scsi_dma_unmap(scp);
 out:
@@ -1631,6 +1629,9 @@ static int init_afu(struct cxlflash_cfg *cfg)
                goto err2;
        }
 
+       afu->send_cmd = send_cmd_ioarrin;
+       afu->context_reset = context_reset_ioarrin;
+
        pr_debug("%s: afu version %s, interface version 0x%llX\n", __func__,
                 afu->version, afu->interface_version);
 
@@ -1723,7 +1724,7 @@ int cxlflash_afu_sync(struct afu *afu, ctx_hndl_t 
ctx_hndl_u,
        *((__be16 *)&cmd->rcb.cdb[2]) = cpu_to_be16(ctx_hndl_u);
        *((__be32 *)&cmd->rcb.cdb[4]) = cpu_to_be32(res_hndl_u);
 
-       rc = send_cmd(afu, cmd);
+       rc = afu->send_cmd(afu, cmd);
        if (unlikely(rc))
                goto out;
 
-- 
2.1.0