igc: Add support for Tx/Rx rings

This change adds the defines and structures necessary to support both Tx
and Rx descriptor rings.

Signed-off-by: Sasha Neftin <sasha.neftin@intel.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
diff --git a/drivers/net/ethernet/intel/igc/igc_base.h b/drivers/net/ethernet/intel/igc/igc_base.h
new file mode 100644
index 0000000..4bdb4ec
--- /dev/null
+++ b/drivers/net/ethernet/intel/igc/igc_base.h
@@ -0,0 +1,89 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/* Copyright (c)  2018 Intel Corporation */
+
+#ifndef _IGC_BASE_H
+#define _IGC_BASE_H
+
+/* forward declaration */
+void igc_rx_fifo_flush_base(struct igc_hw *hw);
+
+/* Transmit Descriptor - Advanced */
+union igc_adv_tx_desc {
+	struct {
+		__le64 buffer_addr;    /* Address of descriptor's data buf */
+		__le32 cmd_type_len;
+		__le32 olinfo_status;
+	} read;
+	struct {
+		__le64 rsvd;       /* Reserved */
+		__le32 nxtseq_seed;
+		__le32 status;
+	} wb;
+};
+
+struct igc_adv_data_desc {
+	__le64 buffer_addr;    /* Address of the descriptor's data buffer */
+	union {
+		u32 data;
+		struct {
+			u32 datalen:16; /* Data buffer length */
+			u32 rsvd:4;
+			u32 dtyp:4;  /* Descriptor type */
+			u32 dcmd:8;  /* Descriptor command */
+		} config;
+	} lower;
+	union {
+		u32 data;
+		struct {
+			u32 status:4;  /* Descriptor status */
+			u32 idx:4;
+			u32 popts:6;  /* Packet Options */
+			u32 paylen:18; /* Payload length */
+		} options;
+	} upper;
+};
+
+/* Receive Descriptor - Advanced */
+union igc_adv_rx_desc {
+	struct {
+		__le64 pkt_addr; /* Packet buffer address */
+		__le64 hdr_addr; /* Header buffer address */
+	} read;
+	struct {
+		struct {
+			union {
+				__le32 data;
+				struct {
+					__le16 pkt_info; /*RSS type, Pkt type*/
+					/* Split Header, header buffer len */
+					__le16 hdr_info;
+				} hs_rss;
+			} lo_dword;
+			union {
+				__le32 rss; /* RSS Hash */
+				struct {
+					__le16 ip_id; /* IP id */
+					__le16 csum; /* Packet Checksum */
+				} csum_ip;
+			} hi_dword;
+		} lower;
+		struct {
+			__le32 status_error; /* ext status/error */
+			__le16 length; /* Packet length */
+			__le16 vlan; /* VLAN tag */
+		} upper;
+	} wb;  /* writeback */
+};
+
+/* Additional Transmit Descriptor Control definitions */
+#define IGC_TXDCTL_QUEUE_ENABLE	0x02000000 /* Ena specific Tx Queue */
+
+/* Additional Receive Descriptor Control definitions */
+#define IGC_RXDCTL_QUEUE_ENABLE	0x02000000 /* Ena specific Rx Queue */
+
+/* SRRCTL bit definitions */
+#define IGC_SRRCTL_BSIZEPKT_SHIFT		10 /* Shift _right_ */
+#define IGC_SRRCTL_BSIZEHDRSIZE_SHIFT		2  /* Shift _left_ */
+#define IGC_SRRCTL_DESCTYPE_ADV_ONEBUF	0x02000000
+
+#endif /* _IGC_BASE_H */