bnxt_en: Retry sending the first message to firmware if it is under reset.

The first HWRM_VER_GET message to firmware during probe may timeout if
firmware is under reset.  This can happen during hot-plug for example.
On P5 and newer chips, we can check if firmware is in the boot stage by
reading a status register.  Retry 5 times if the status register shows
that firmware is not ready and not in error state.
Reviewed-by: Edwin Peer <edwin.peer@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/ethernet/broadcom/bnxt/bnxt.c

@@ -7441,9 +7441,22 @@ static void bnxt_try_map_fw_health_reg(struct bnxt *bp)
 
 	sig = readl(hs + offsetof(struct hcomm_status, sig_ver));
 	if ((sig & HCOMM_STATUS_SIGNATURE_MASK) != HCOMM_STATUS_SIGNATURE_VAL) {
-		if (bp->fw_health)
-			bp->fw_health->status_reliable = false;
-		return;
+		if (!bp->chip_num) {
+			__bnxt_map_fw_health_reg(bp, BNXT_GRC_REG_BASE);
+			bp->chip_num = readl(bp->bar0 +
+					     BNXT_FW_HEALTH_WIN_BASE +
+					     BNXT_GRC_REG_CHIP_NUM);
+		}
+		if (!BNXT_CHIP_P5(bp)) {
+			if (bp->fw_health)
+				bp->fw_health->status_reliable = false;
+			return;
+		}
+		status_loc = BNXT_GRC_REG_STATUS_P5 |
+			     BNXT_FW_HEALTH_REG_TYPE_BAR0;
+	} else {
+		status_loc = readl(hs + offsetof(struct hcomm_status,
+						 fw_status_loc));
 	}
 
 	if (__bnxt_alloc_fw_health(bp)) {
@@ -7451,7 +7464,6 @@ static void bnxt_try_map_fw_health_reg(struct bnxt *bp)
 		return;
 	}
 
-	status_loc = readl(hs + offsetof(struct hcomm_status, fw_status_loc));
 	bp->fw_health->regs[BNXT_FW_HEALTH_REG] = status_loc;
 	reg_type = BNXT_FW_HEALTH_REG_TYPE(status_loc);
 	if (reg_type == BNXT_FW_HEALTH_REG_TYPE_GRC) {
@@ -9355,14 +9367,30 @@ static int bnxt_fw_reset_via_optee(struct bnxt *bp)
 static int bnxt_try_recover_fw(struct bnxt *bp)
 {
 	if (bp->fw_health && bp->fw_health->status_reliable) {
-		u32 sts = bnxt_fw_health_readl(bp, BNXT_FW_HEALTH_REG);
+		int retry = 0, rc;
+		u32 sts;
+
+		mutex_lock(&bp->hwrm_cmd_lock);
+		do {
+			rc = __bnxt_hwrm_ver_get(bp, true);
+			sts = bnxt_fw_health_readl(bp, BNXT_FW_HEALTH_REG);
+			if (!sts || !BNXT_FW_IS_BOOTING(sts))
+				break;
+			retry++;
+		} while (rc == -EBUSY && retry < BNXT_FW_RETRY);
+		mutex_unlock(&bp->hwrm_cmd_lock);
 
-		netdev_err(bp->dev, "Firmware not responding, status: 0x%x\n",
-			   sts);
+		if (!BNXT_FW_IS_HEALTHY(sts)) {
+			netdev_err(bp->dev,
+				   "Firmware not responding, status: 0x%x\n",
+				   sts);
+			rc = -ENODEV;
+		}
 		if (sts & FW_STATUS_REG_CRASHED_NO_MASTER) {
 			netdev_warn(bp->dev, "Firmware recover via OP-TEE requested\n");
 			return bnxt_fw_reset_via_optee(bp);
 		}
+		return rc;
 	}
 
 	return -ENODEV;

drivers/net/ethernet/broadcom/bnxt/bnxt.h

@@ -1345,9 +1345,14 @@ struct bnxt_test_info {
 #define BNXT_CAG_REG_LEGACY_INT_STATUS		0x4014
 #define BNXT_CAG_REG_BASE			0x300000
 
+#define BNXT_GRC_REG_STATUS_P5			0x520
+
 #define BNXT_GRCPF_REG_KONG_COMM		0xA00
 #define BNXT_GRCPF_REG_KONG_COMM_TRIGGER	0xB00
 
+#define BNXT_GRC_REG_CHIP_NUM			0x48
+#define BNXT_GRC_REG_BASE			0x260000
+
 #define BNXT_GRC_BASE_MASK			0xfffff000
 #define BNXT_GRC_OFFSET_MASK			0x00000ffc
 
@@ -1547,6 +1552,8 @@ struct bnxt_fw_reporter_ctx {
 #define BNXT_FW_IS_ERR(sts)		(((sts) & BNXT_FW_STATUS_HEALTH_MSK) > \
 					 BNXT_FW_STATUS_HEALTHY)
 
+#define BNXT_FW_RETRY			5
+
 struct bnxt {
 	void __iomem		*bar0;
 	void __iomem		*bar1;