ionic: add polling to adminq wait

Split the adminq wait into smaller polling periods in order
to watch for broken firmware and not have to wait for the full
adminq devcmd_timeout.

Generally, adminq commands take fewer than 2 msecs.  If the
FW is busy they can take longer, but usually still under 100
msecs.  We set the polling period to 100 msecs in order to
start snooping on FW status when a command is taking longer
than usual.
Signed-off-by: Shannon Nelson <snelson@pensando.io>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/pensando/ionic/ionic.h

@@ -19,6 +19,7 @@ struct ionic_lif;
 #define PCI_DEVICE_ID_PENSANDO_IONIC_ETH_VF	0x1003
 
 #define DEVCMD_TIMEOUT  10
+#define IONIC_ADMINQ_TIME_SLICE		msecs_to_jiffies(100)
 
 #define IONIC_PHC_UPDATE_NS	10000000000	    /* 10s in nanoseconds */
 #define NORMAL_PPB		1000000000	    /* one billion parts per billion */

drivers/net/ethernet/pensando/ionic/ionic_main.c

@@ -301,21 +301,45 @@ int ionic_adminq_post(struct ionic_lif *lif, struct ionic_admin_ctx *ctx)
 int ionic_adminq_wait(struct ionic_lif *lif, struct ionic_admin_ctx *ctx, int err)
 {
 	struct net_device *netdev = lif->netdev;
+	unsigned long time_limit;
+	unsigned long time_start;
+	unsigned long time_done;
 	unsigned long remaining;
 	const char *name;
 
+	name = ionic_opcode_to_str(ctx->cmd.cmd.opcode);
+
 	if (err) {
-		if (!test_bit(IONIC_LIF_F_FW_RESET, lif->state)) {
-			name = ionic_opcode_to_str(ctx->cmd.cmd.opcode);
+		if (!test_bit(IONIC_LIF_F_FW_RESET, lif->state))
 			netdev_err(netdev, "Posting of %s (%d) failed: %d\n",
 				   name, ctx->cmd.cmd.opcode, err);
-		}
 		return err;
 	}
 
-	remaining = wait_for_completion_timeout(&ctx->work,
-						HZ * (ulong)DEVCMD_TIMEOUT);
-	return ionic_adminq_check_err(lif, ctx, (remaining == 0));
+	time_start = jiffies;
+	time_limit = time_start + HZ * (ulong)DEVCMD_TIMEOUT;
+	do {
+		remaining = wait_for_completion_timeout(&ctx->work,
+							IONIC_ADMINQ_TIME_SLICE);
+
+		/* check for done */
+		if (remaining)
+			break;
+
+		/* interrupt the wait if FW stopped */
+		if (test_bit(IONIC_LIF_F_FW_RESET, lif->state)) {
+			netdev_err(netdev, "%s (%d) interrupted, FW in reset\n",
+				   name, ctx->cmd.cmd.opcode);
+			return -ENXIO;
+		}
+
+	} while (time_before(jiffies, time_limit));
+	time_done = jiffies;
+
+	dev_dbg(lif->ionic->dev, "%s: elapsed %d msecs\n",
+		__func__, jiffies_to_msecs(time_done - time_start));
+
+	return ionic_adminq_check_err(lif, ctx, time_after_eq(time_done, time_limit));
 }
 
 int ionic_adminq_post_wait(struct ionic_lif *lif, struct ionic_admin_ctx *ctx)