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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
commitace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch)
treeb2d64bc10158fdd5497876388cd68142ca374ed3 /drivers/net/ethernet/google/gve/gve_desc.h
parentInitial commit. (diff)
downloadlinux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz
linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/net/ethernet/google/gve/gve_desc.h')
-rw-r--r--drivers/net/ethernet/google/gve/gve_desc.h139
1 files changed, 139 insertions, 0 deletions
diff --git a/drivers/net/ethernet/google/gve/gve_desc.h b/drivers/net/ethernet/google/gve/gve_desc.h
new file mode 100644
index 0000000000..c2874cdcf4
--- /dev/null
+++ b/drivers/net/ethernet/google/gve/gve_desc.h
@@ -0,0 +1,139 @@
+/* SPDX-License-Identifier: (GPL-2.0 OR MIT)
+ * Google virtual Ethernet (gve) driver
+ *
+ * Copyright (C) 2015-2019 Google, Inc.
+ */
+
+/* GVE Transmit Descriptor formats */
+
+#ifndef _GVE_DESC_H_
+#define _GVE_DESC_H_
+
+#include <linux/build_bug.h>
+
+/* A note on seg_addrs
+ *
+ * Base addresses encoded in seg_addr are not assumed to be physical
+ * addresses. The ring format assumes these come from some linear address
+ * space. This could be physical memory, kernel virtual memory, user virtual
+ * memory.
+ * If raw dma addressing is not supported then gVNIC uses lists of registered
+ * pages. Each queue is assumed to be associated with a single such linear
+ * address space to ensure a consistent meaning for seg_addrs posted to its
+ * rings.
+ */
+
+struct gve_tx_pkt_desc {
+ u8 type_flags; /* desc type is lower 4 bits, flags upper */
+ u8 l4_csum_offset; /* relative offset of L4 csum word */
+ u8 l4_hdr_offset; /* Offset of start of L4 headers in packet */
+ u8 desc_cnt; /* Total descriptors for this packet */
+ __be16 len; /* Total length of this packet (in bytes) */
+ __be16 seg_len; /* Length of this descriptor's segment */
+ __be64 seg_addr; /* Base address (see note) of this segment */
+} __packed;
+
+struct gve_tx_mtd_desc {
+ u8 type_flags; /* type is lower 4 bits, subtype upper */
+ u8 path_state; /* state is lower 4 bits, hash type upper */
+ __be16 reserved0;
+ __be32 path_hash;
+ __be64 reserved1;
+} __packed;
+
+struct gve_tx_seg_desc {
+ u8 type_flags; /* type is lower 4 bits, flags upper */
+ u8 l3_offset; /* TSO: 2 byte units to start of IPH */
+ __be16 reserved;
+ __be16 mss; /* TSO MSS */
+ __be16 seg_len;
+ __be64 seg_addr;
+} __packed;
+
+/* GVE Transmit Descriptor Types */
+#define GVE_TXD_STD (0x0 << 4) /* Std with Host Address */
+#define GVE_TXD_TSO (0x1 << 4) /* TSO with Host Address */
+#define GVE_TXD_SEG (0x2 << 4) /* Seg with Host Address */
+#define GVE_TXD_MTD (0x3 << 4) /* Metadata */
+
+/* GVE Transmit Descriptor Flags for Std Pkts */
+#define GVE_TXF_L4CSUM BIT(0) /* Need csum offload */
+#define GVE_TXF_TSTAMP BIT(2) /* Timestamp required */
+
+/* GVE Transmit Descriptor Flags for TSO Segs */
+#define GVE_TXSF_IPV6 BIT(1) /* IPv6 TSO */
+
+/* GVE Transmit Descriptor Options for MTD Segs */
+#define GVE_MTD_SUBTYPE_PATH 0
+
+#define GVE_MTD_PATH_STATE_DEFAULT 0
+#define GVE_MTD_PATH_STATE_TIMEOUT 1
+#define GVE_MTD_PATH_STATE_CONGESTION 2
+#define GVE_MTD_PATH_STATE_RETRANSMIT 3
+
+#define GVE_MTD_PATH_HASH_NONE (0x0 << 4)
+#define GVE_MTD_PATH_HASH_L4 (0x1 << 4)
+
+/* GVE Receive Packet Descriptor */
+/* The start of an ethernet packet comes 2 bytes into the rx buffer.
+ * gVNIC adds this padding so that both the DMA and the L3/4 protocol header
+ * access is aligned.
+ */
+#define GVE_RX_PAD 2
+
+struct gve_rx_desc {
+ u8 padding[48];
+ __be32 rss_hash; /* Receive-side scaling hash (Toeplitz for gVNIC) */
+ __be16 mss;
+ __be16 reserved; /* Reserved to zero */
+ u8 hdr_len; /* Header length (L2-L4) including padding */
+ u8 hdr_off; /* 64-byte-scaled offset into RX_DATA entry */
+ __sum16 csum; /* 1's-complement partial checksum of L3+ bytes */
+ __be16 len; /* Length of the received packet */
+ __be16 flags_seq; /* Flags [15:3] and sequence number [2:0] (1-7) */
+} __packed;
+static_assert(sizeof(struct gve_rx_desc) == 64);
+
+/* If the device supports raw dma addressing then the addr in data slot is
+ * the dma address of the buffer.
+ * If the device only supports registered segments then the addr is a byte
+ * offset into the registered segment (an ordered list of pages) where the
+ * buffer is.
+ */
+union gve_rx_data_slot {
+ __be64 qpl_offset;
+ __be64 addr;
+};
+
+/* GVE Receive Packet Descriptor Seq No */
+#define GVE_SEQNO(x) (be16_to_cpu(x) & 0x7)
+
+/* GVE Receive Packet Descriptor Flags */
+#define GVE_RXFLG(x) cpu_to_be16(1 << (3 + (x)))
+#define GVE_RXF_FRAG GVE_RXFLG(3) /* IP Fragment */
+#define GVE_RXF_IPV4 GVE_RXFLG(4) /* IPv4 */
+#define GVE_RXF_IPV6 GVE_RXFLG(5) /* IPv6 */
+#define GVE_RXF_TCP GVE_RXFLG(6) /* TCP Packet */
+#define GVE_RXF_UDP GVE_RXFLG(7) /* UDP Packet */
+#define GVE_RXF_ERR GVE_RXFLG(8) /* Packet Error Detected */
+#define GVE_RXF_PKT_CONT GVE_RXFLG(10) /* Multi Fragment RX packet */
+
+/* GVE IRQ */
+#define GVE_IRQ_ACK BIT(31)
+#define GVE_IRQ_MASK BIT(30)
+#define GVE_IRQ_EVENT BIT(29)
+
+static inline bool gve_needs_rss(__be16 flag)
+{
+ if (flag & GVE_RXF_FRAG)
+ return false;
+ if (flag & (GVE_RXF_IPV4 | GVE_RXF_IPV6))
+ return true;
+ return false;
+}
+
+static inline u8 gve_next_seqno(u8 seq)
+{
+ return (seq + 1) == 8 ? 1 : seq + 1;
+}
+#endif /* _GVE_DESC_H_ */