ionic: Don't send reset commands if FW isn't running

It's possible the FW is already shutting down while the driver is being
removed and/or when the driver is going through reset. This can cause
unexpected/unnecessary errors to be printed:

eth0: DEV_CMD IONIC_CMD_PORT_RESET (12) error, IONIC_RC_ERROR (29) failed
eth1: DEV_CMD IONIC_CMD_RESET (3) error, IONIC_RC_ERROR (29) failed

Fix this by checking the FW status register before issuing the reset
commands.

Also, since err may not be assigned in ionic_port_reset(), assign it a
default value of 0, and remove an unnecessary log message.

Fixes: fbfb803153 ("ionic: Add hardware init and device commands")
Signed-off-by: Brett Creeley <brett@pensando.io>
Signed-off-by: Shannon Nelson <snelson@pensando.io>
Signed-off-by: David S. Miller <davem@davemloft.net>

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

@@ -136,6 +136,16 @@ int ionic_dev_setup(struct ionic *ionic)
 }
 
 /* Devcmd Interface */
+bool ionic_is_fw_running(struct ionic_dev *idev)
+{
+	u8 fw_status = ioread8(&idev->dev_info_regs->fw_status);
+
+	/* firmware is useful only if the running bit is set and
+	 * fw_status != 0xff (bad PCI read)
+	 */
+	return (fw_status != 0xff) && (fw_status & IONIC_FW_STS_F_RUNNING);
+}
+
 int ionic_heartbeat_check(struct ionic *ionic)
 {
 	struct ionic_dev *idev = &ionic->idev;
@@ -159,13 +169,10 @@ do_check_time:
 		goto do_check_time;
 	}
 
-	/* firmware is useful only if the running bit is set and
-	 * fw_status != 0xff (bad PCI read)
-	 * If fw_status is not ready don't bother with the generation.
-	 */
 	fw_status = ioread8(&idev->dev_info_regs->fw_status);
 
-	if (fw_status == 0xff || !(fw_status & IONIC_FW_STS_F_RUNNING)) {
+	/* If fw_status is not ready don't bother with the generation */
+	if (!ionic_is_fw_running(idev)) {
 		fw_status_ready = false;
 	} else {
 		fw_generation = fw_status & IONIC_FW_STS_F_GENERATION;

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

@@ -353,5 +353,6 @@ void ionic_q_rewind(struct ionic_queue *q, struct ionic_desc_info *start);
 void ionic_q_service(struct ionic_queue *q, struct ionic_cq_info *cq_info,
 		     unsigned int stop_index);
 int ionic_heartbeat_check(struct ionic *ionic);
+bool ionic_is_fw_running(struct ionic_dev *idev);
 
 #endif /* _IONIC_DEV_H_ */

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

@@ -540,6 +540,9 @@ int ionic_reset(struct ionic *ionic)
 	struct ionic_dev *idev = &ionic->idev;
 	int err;
 
+	if (!ionic_is_fw_running(idev))
+		return 0;
+
 	mutex_lock(&ionic->dev_cmd_lock);
 	ionic_dev_cmd_reset(idev);
 	err = ionic_dev_cmd_wait(ionic, DEVCMD_TIMEOUT);
@@ -612,15 +615,17 @@ int ionic_port_init(struct ionic *ionic)
 int ionic_port_reset(struct ionic *ionic)
 {
 	struct ionic_dev *idev = &ionic->idev;
-	int err;
+	int err = 0;
 
 	if (!idev->port_info)
 		return 0;
 
-	mutex_lock(&ionic->dev_cmd_lock);
-	ionic_dev_cmd_port_reset(idev);
-	err = ionic_dev_cmd_wait(ionic, DEVCMD_TIMEOUT);
-	mutex_unlock(&ionic->dev_cmd_lock);
+	if (ionic_is_fw_running(idev)) {
+		mutex_lock(&ionic->dev_cmd_lock);
+		ionic_dev_cmd_port_reset(idev);
+		err = ionic_dev_cmd_wait(ionic, DEVCMD_TIMEOUT);
+		mutex_unlock(&ionic->dev_cmd_lock);
+	}
 
 	dma_free_coherent(ionic->dev, idev->port_info_sz,
 			  idev->port_info, idev->port_info_pa);
@@ -628,9 +633,6 @@ int ionic_port_reset(struct ionic *ionic)
 	idev->port_info = NULL;
 	idev->port_info_pa = 0;
 
-	if (err)
-		dev_err(ionic->dev, "Failed to reset port\n");
-
 	return err;
 }