bnxt_en: Implement proper firmware message padding.

The size of every padded firmware message is specified in the first
HWRM_VER_GET response message.  Use this value to pad every message
after that.

Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
index c92053c..4600a05 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
@@ -2653,7 +2653,7 @@
 	/* Write request msg to hwrm channel */
 	__iowrite32_copy(bp->bar0, data, msg_len / 4);
 
-	for (i = msg_len; i < HWRM_MAX_REQ_LEN; i += 4)
+	for (i = msg_len; i < BNXT_HWRM_MAX_REQ_LEN; i += 4)
 		writel(0, bp->bar0 + i);
 
 	/* currently supports only one outstanding message */
@@ -3830,6 +3830,7 @@
 	struct hwrm_ver_get_input req = {0};
 	struct hwrm_ver_get_output *resp = bp->hwrm_cmd_resp_addr;
 
+	bp->hwrm_max_req_len = HWRM_MAX_REQ_LEN;
 	bnxt_hwrm_cmd_hdr_init(bp, &req, HWRM_VER_GET, -1, -1);
 	req.hwrm_intf_maj = HWRM_VERSION_MAJOR;
 	req.hwrm_intf_min = HWRM_VERSION_MINOR;
@@ -3855,6 +3856,9 @@
 	if (!bp->hwrm_cmd_timeout)
 		bp->hwrm_cmd_timeout = DFLT_HWRM_CMD_TIMEOUT;
 
+	if (resp->hwrm_intf_maj >= 1)
+		bp->hwrm_max_req_len = le16_to_cpu(resp->max_req_win_len);
+
 hwrm_ver_get_exit:
 	mutex_unlock(&bp->hwrm_cmd_lock);
 	return rc;
diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.h b/drivers/net/ethernet/broadcom/bnxt/bnxt.h
index ec04c47..709b95b 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.h
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.h
@@ -477,6 +477,7 @@
 #define RING_CMP(idx)		((idx) & bp->cp_ring_mask)
 #define NEXT_CMP(idx)		RING_CMP(ADV_RAW_CMP(idx, 1))
 
+#define BNXT_HWRM_MAX_REQ_LEN		(bp->hwrm_max_req_len)
 #define DFLT_HWRM_CMD_TIMEOUT		500
 #define HWRM_CMD_TIMEOUT		(bp->hwrm_cmd_timeout)
 #define HWRM_RESET_TIMEOUT		((HWRM_CMD_TIMEOUT) * 4)
@@ -953,6 +954,7 @@
 	dma_addr_t		hw_tx_port_stats_map;
 	int			hw_port_stats_size;
 
+	u16			hwrm_max_req_len;
 	int			hwrm_cmd_timeout;
 	struct mutex		hwrm_cmd_lock;	/* serialize hwrm messages */
 	struct hwrm_ver_get_output	ver_resp;