nfp: read mailbox address from TLV caps

Allow specifying alternative vNIC mailbox location in TLV caps.
This way we can size the mailbox to the needs and not necessarily
waste 512B of ctrl memory space.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Dirk van der Merwe <dirk.vandermerwe@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/netronome/nfp/nfp_net_common.c

@@ -293,9 +293,15 @@ int nfp_net_reconfig(struct nfp_net *nn, u32 update)
  */
 static int nfp_net_reconfig_mbox(struct nfp_net *nn, u32 mbox_cmd)
 {
+	u32 mbox = nn->tlv_caps.mbox_off;
 	int ret;
 
-	nn_writeq(nn, NFP_NET_CFG_MBOX_CMD, mbox_cmd);
+	if (!nfp_net_has_mbox(&nn->tlv_caps)) {
+		nn_err(nn, "no mailbox present, command: %u\n", mbox_cmd);
+		return -EIO;
+	}
+
+	nn_writeq(nn, mbox + NFP_NET_CFG_MBOX_SIMPLE_CMD, mbox_cmd);
 
 	ret = nfp_net_reconfig(nn, NFP_NET_CFG_UPDATE_MBOX);
 	if (ret) {
@@ -303,7 +309,7 @@ static int nfp_net_reconfig_mbox(struct nfp_net *nn, u32 mbox_cmd)
 		return ret;
 	}
 
-	return -nn_readl(nn, NFP_NET_CFG_MBOX_RET);
+	return -nn_readl(nn, mbox + NFP_NET_CFG_MBOX_SIMPLE_RET);
 }
 
 /* Interrupt configuration and handling
@@ -3084,8 +3090,9 @@ nfp_net_vlan_rx_add_vid(struct net_device *netdev, __be16 proto, u16 vid)
 	if (!vid)
 		return 0;
 
-	nn_writew(nn, NFP_NET_CFG_VLAN_FILTER_VID, vid);
-	nn_writew(nn, NFP_NET_CFG_VLAN_FILTER_PROTO, ETH_P_8021Q);
+	nn_writew(nn, nn->tlv_caps.mbox_off + NFP_NET_CFG_VLAN_FILTER_VID, vid);
+	nn_writew(nn, nn->tlv_caps.mbox_off + NFP_NET_CFG_VLAN_FILTER_PROTO,
+		  ETH_P_8021Q);
 
 	return nfp_net_reconfig_mbox(nn, NFP_NET_CFG_MBOX_CMD_CTAG_FILTER_ADD);
 }
@@ -3101,8 +3108,9 @@ nfp_net_vlan_rx_kill_vid(struct net_device *netdev, __be16 proto, u16 vid)
 	if (!vid)
 		return 0;
 
-	nn_writew(nn, NFP_NET_CFG_VLAN_FILTER_VID, vid);
-	nn_writew(nn, NFP_NET_CFG_VLAN_FILTER_PROTO, ETH_P_8021Q);
+	nn_writew(nn, nn->tlv_caps.mbox_off + NFP_NET_CFG_VLAN_FILTER_VID, vid);
+	nn_writew(nn, nn->tlv_caps.mbox_off + NFP_NET_CFG_VLAN_FILTER_PROTO,
+		  ETH_P_8021Q);
 
 	return nfp_net_reconfig_mbox(nn, NFP_NET_CFG_MBOX_CMD_CTAG_FILTER_KILL);
 }

drivers/net/ethernet/netronome/nfp/nfp_net_ctrl.c

@@ -43,6 +43,8 @@ static void nfp_net_tlv_caps_reset(struct nfp_net_tlv_caps *caps)
 {
 	memset(caps, 0, sizeof(*caps));
 	caps->me_freq_mhz = 1200;
+	caps->mbox_off = NFP_NET_CFG_MBOX_BASE;
+	caps->mbox_len = NFP_NET_CFG_MBOX_VAL_MAX_SZ;
 }
 
 int nfp_net_tlv_caps_parse(struct device *dev, u8 __iomem *ctrl_mem,
@@ -102,6 +104,15 @@ int nfp_net_tlv_caps_parse(struct device *dev, u8 __iomem *ctrl_mem,
 
 			caps->me_freq_mhz = readl(data);
 			break;
+		case NFP_NET_CFG_TLV_TYPE_MBOX:
+			if (!length) {
+				caps->mbox_off = 0;
+				caps->mbox_len = 0;
+			} else {
+				caps->mbox_off = data - ctrl_mem;
+				caps->mbox_len = length;
+			}
+			break;
 		default:
 			if (!FIELD_GET(NFP_NET_CFG_TLV_HEADER_REQUIRED, hdr))
 				break;

drivers/net/ethernet/netronome/nfp/nfp_net_ctrl.h

@@ -413,11 +413,14 @@
  * 4B used for update command and 4B return code
  * followed by a max of 504B of variable length value
  */
-#define NFP_NET_CFG_MBOX_CMD		0x1800
-#define NFP_NET_CFG_MBOX_RET		0x1804
-#define NFP_NET_CFG_MBOX_VAL		0x1808
+#define NFP_NET_CFG_MBOX_BASE		0x1800
 #define NFP_NET_CFG_MBOX_VAL_MAX_SZ	0x1F8
 
+#define NFP_NET_CFG_MBOX_SIMPLE_CMD	0x0
+#define NFP_NET_CFG_MBOX_SIMPLE_RET	0x4
+#define NFP_NET_CFG_MBOX_SIMPLE_VAL	0x8
+#define NFP_NET_CFG_MBOX_SIMPLE_LEN	0x12
+
 #define NFP_NET_CFG_MBOX_CMD_CTAG_FILTER_ADD 1
 #define NFP_NET_CFG_MBOX_CMD_CTAG_FILTER_KILL 2
 
@@ -428,7 +431,7 @@
  * %NFP_NET_CFG_VLAN_FILTER_PROTO:	VLAN proto to filter
  * %NFP_NET_CFG_VXLAN_SZ:		Size of the VLAN filter mailbox in bytes
  */
-#define NFP_NET_CFG_VLAN_FILTER		NFP_NET_CFG_MBOX_VAL
+#define NFP_NET_CFG_VLAN_FILTER		NFP_NET_CFG_MBOX_SIMPLE_VAL
 #define  NFP_NET_CFG_VLAN_FILTER_VID	NFP_NET_CFG_VLAN_FILTER
 #define  NFP_NET_CFG_VLAN_FILTER_PROTO	 (NFP_NET_CFG_VLAN_FILTER + 2)
 #define NFP_NET_CFG_VLAN_FILTER_SZ	 0x0004
@@ -478,23 +481,37 @@
  * %NFP_NET_CFG_TLV_TYPE_ME_FREQ:
  * Single word, ME frequency in MHz as used in calculation for
  * %NFP_NET_CFG_RXR_IRQ_MOD and %NFP_NET_CFG_TXR_IRQ_MOD.
+ *
+ * %NFP_NET_CFG_TLV_TYPE_MBOX:
+ * Variable, mailbox area.  Overwrites the default location which is
+ * %NFP_NET_CFG_MBOX_BASE and length %NFP_NET_CFG_MBOX_VAL_MAX_SZ.
  */
 #define NFP_NET_CFG_TLV_TYPE_UNKNOWN		0
 #define NFP_NET_CFG_TLV_TYPE_RESERVED		1
 #define NFP_NET_CFG_TLV_TYPE_END		2
 #define NFP_NET_CFG_TLV_TYPE_ME_FREQ		3
+#define NFP_NET_CFG_TLV_TYPE_MBOX		4
 
 struct device;
 
 /**
  * struct nfp_net_tlv_caps - parsed control BAR TLV capabilities
  * @me_freq_mhz:	ME clock_freq (MHz)
+ * @mbox_off:		vNIC mailbox area offset
+ * @mbox_len:		vNIC mailbox area length
  */
 struct nfp_net_tlv_caps {
 	u32 me_freq_mhz;
+	unsigned int mbox_off;
+	unsigned int mbox_len;
 };
 
 int nfp_net_tlv_caps_parse(struct device *dev, u8 __iomem *ctrl_mem,
 			   struct nfp_net_tlv_caps *caps);
 
+static inline bool nfp_net_has_mbox(struct nfp_net_tlv_caps *caps)
+{
+	return caps->mbox_len >= NFP_NET_CFG_MBOX_SIMPLE_LEN;
+}
+
 #endif /* _NFP_NET_CTRL_H_ */