RDMA/bnxt_re: Enhance the existing functions that wait for FW responses

Use jiffies based timewait instead of counting iteration for
commands that block for FW response.

Also add a poll routine for control path commands. This is for
polling completion if the waiting commands timeout. This avoids cases
where the driver misses completion interrupts.

Signed-off-by: Kashyap Desai <kashyap.desai@broadcom.com>
Signed-off-by: Selvin Xavier <selvin.xavier@broadcom.com>
Link: https://lore.kernel.org/r/1686308514-11996-6-git-send-email-selvin.xavier@broadcom.com
Signed-off-by: Leon Romanovsky <leon@kernel.org>

diff --git a/drivers/infiniband/hw/bnxt_re/qplib_rcfw.c b/drivers/infiniband/hw/bnxt_re/qplib_rcfw.c
index 66121fb..3b242cc 100644 (file)
--- a/drivers/infiniband/hw/bnxt_re/qplib_rcfw.c
+++ b/drivers/infiniband/hw/bnxt_re/qplib_rcfw.c
@@ -53,37 +53,74 @@
 
 static void bnxt_qplib_service_creq(struct tasklet_struct *t);
 
-/* Hardware communication channel */
+/**
+ * __wait_for_resp   - Don't hold the cpu context and wait for response
+ * @rcfw      -   rcfw channel instance of rdev
+ * @cookie    -   cookie to track the command
+ *
+ * Wait for command completion in sleepable context.
+ *
+ * Returns:
+ * 0 if command is completed by firmware.
+ * Non zero error code for rest of the case.
+ */
 static int __wait_for_resp(struct bnxt_qplib_rcfw *rcfw, u16 cookie)
 {
        struct bnxt_qplib_cmdq_ctx *cmdq;
        u16 cbit;
-       int rc;
+       int ret;
 
        cmdq = &rcfw->cmdq;
        cbit = cookie % rcfw->cmdq_depth;
-       rc = wait_event_timeout(cmdq->waitq,
-                               !test_bit(cbit, cmdq->cmdq_bitmap),
-                               msecs_to_jiffies(RCFW_CMD_WAIT_TIME_MS));
-       return rc ? 0 : -ETIMEDOUT;
+
+       do {
+               /* Non zero means command completed */
+               ret = wait_event_timeout(cmdq->waitq,
+                                        !test_bit(cbit, cmdq->cmdq_bitmap),
+                                        msecs_to_jiffies(10000));
+
+               if (!test_bit(cbit, cmdq->cmdq_bitmap))
+                       return 0;
+
+               bnxt_qplib_service_creq(&rcfw->creq.creq_tasklet);
+
+               if (!test_bit(cbit, cmdq->cmdq_bitmap))
+                       return 0;
+
+       } while (true);
 };
 
+/**
+ * __block_for_resp   -        hold the cpu context and wait for response
+ * @rcfw      -   rcfw channel instance of rdev
+ * @cookie    -   cookie to track the command
+ *
+ * This function will hold the cpu (non-sleepable context) and
+ * wait for command completion. Maximum holding interval is 8 second.
+ *
+ * Returns:
+ * -ETIMEOUT if command is not completed in specific time interval.
+ * 0 if command is completed by firmware.
+ */
 static int __block_for_resp(struct bnxt_qplib_rcfw *rcfw, u16 cookie)
 {
-       u32 count = RCFW_BLOCKED_CMD_WAIT_COUNT;
-       struct bnxt_qplib_cmdq_ctx *cmdq;
+       struct bnxt_qplib_cmdq_ctx *cmdq = &rcfw->cmdq;
+       unsigned long issue_time = 0;
        u16 cbit;
 
-       cmdq = &rcfw->cmdq;
        cbit = cookie % rcfw->cmdq_depth;
-       if (!test_bit(cbit, cmdq->cmdq_bitmap))
-               goto done;
+       issue_time = jiffies;
+
        do {
                udelay(1);
+
                bnxt_qplib_service_creq(&rcfw->creq.creq_tasklet);
-       } while (test_bit(cbit, cmdq->cmdq_bitmap) && --count);
-done:
-       return count ? 0 : -ETIMEDOUT;
+               if (!test_bit(cbit, cmdq->cmdq_bitmap))
+                       return 0;
+
+       } while (time_before(jiffies, issue_time + (8 * HZ)));
+
+       return -ETIMEDOUT;
 };
 
 static int __send_message(struct bnxt_qplib_rcfw *rcfw,