1 /* SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) */
2 /* Copyright (C) 2019 Netronome Systems, Inc. */
3
4 #ifndef _NFP_DP_NFDK_H_
5 #define _NFP_DP_NFDK_H_
6
7 #include <linux/bitops.h>
8 #include <linux/types.h>
9
10 #define NFDK_TX_DESC_PER_SIMPLE_PKT 2
11
12 #define NFDK_TX_MAX_DATA_PER_HEAD SZ_4K
13 #define NFDK_TX_MAX_DATA_PER_DESC SZ_16K
14 #define NFDK_TX_DESC_BLOCK_SZ 256
15 #define NFDK_TX_DESC_BLOCK_CNT (NFDK_TX_DESC_BLOCK_SZ / \
16 sizeof(struct nfp_nfdk_tx_desc))
17 #define NFDK_TX_DESC_STOP_CNT (NFDK_TX_DESC_BLOCK_CNT * \
18 NFDK_TX_DESC_PER_SIMPLE_PKT)
19 #define NFDK_TX_MAX_DATA_PER_BLOCK SZ_64K
20 #define NFDK_TX_DESC_GATHER_MAX 17
21
22 /* TX descriptor format */
23
24 #define NFDK_DESC_TX_MSS_MASK GENMASK(13, 0)
25
26 #define NFDK_DESC_TX_CHAIN_META BIT(3)
27 #define NFDK_DESC_TX_ENCAP BIT(2)
28 #define NFDK_DESC_TX_L4_CSUM BIT(1)
29 #define NFDK_DESC_TX_L3_CSUM BIT(0)
30
31 #define NFDK_DESC_TX_DMA_LEN_HEAD GENMASK(11, 0)
32 #define NFDK_DESC_TX_TYPE_HEAD GENMASK(15, 12)
33 #define NFDK_DESC_TX_DMA_LEN GENMASK(13, 0)
34 #define NFDK_DESC_TX_TYPE_NOP 0
35 #define NFDK_DESC_TX_TYPE_GATHER 1
36 #define NFDK_DESC_TX_TYPE_TSO 2
37 #define NFDK_DESC_TX_TYPE_SIMPLE 8
38 #define NFDK_DESC_TX_EOP BIT(14)
39
40 #define NFDK_META_LEN GENMASK(7, 0)
41 #define NFDK_META_FIELDS GENMASK(31, 8)
42
43 #define D_BLOCK_CPL(idx) (NFDK_TX_DESC_BLOCK_CNT - \
44 (idx) % NFDK_TX_DESC_BLOCK_CNT)
45
46 struct nfp_nfdk_tx_desc {
47 union {
48 struct {
49 __le16 dma_addr_hi; /* High bits of host buf address */
50 __le16 dma_len_type; /* Length to DMA for this desc */
51 __le32 dma_addr_lo; /* Low 32bit of host buf addr */
52 };
53
54 struct {
55 __le16 mss; /* MSS to be used for LSO */
56 u8 lso_hdrlen; /* LSO, TCP payload offset */
57 u8 lso_totsegs; /* LSO, total segments */
58 u8 l3_offset; /* L3 header offset */
59 u8 l4_offset; /* L4 header offset */
60 __le16 lso_meta_res; /* Rsvd bits in TSO metadata */
61 };
62
63 struct {
64 u8 flags; /* TX Flags, see @NFDK_DESC_TX_* */
65 u8 reserved[7]; /* meta byte placeholder */
66 };
67
68 __le32 vals[2];
69 __le64 raw;
70 };
71 };
72
73 /* The device don't make use of the 2 or 3 least significant bits of the address
74 * due to alignment constraints. The driver can make use of those bits to carry
75 * information about the buffer before giving it to the device.
76 *
77 * NOTE: The driver must clear the lower bits before handing the buffer to the
78 * device.
79 *
80 * - NFDK_TX_BUF_INFO_SOP - Start of a packet
81 * Mark the buffer as a start of a packet. This is used in the XDP TX process
82 * to stash virtual and DMA address so that they can be recycled when the TX
83 * operation is completed.
84 */
85 #define NFDK_TX_BUF_PTR(val) ((val) & ~(sizeof(void *) - 1))
86 #define NFDK_TX_BUF_INFO(val) ((val) & (sizeof(void *) - 1))
87 #define NFDK_TX_BUF_INFO_SOP BIT(0)
88
89 struct nfp_nfdk_tx_buf {
90 union {
91 /* First slot */
92 union {
93 struct sk_buff *skb;
94 void *frag;
95 unsigned long val;
96 };
97
98 /* 1 + nr_frags next slots */
99 dma_addr_t dma_addr;
100
101 /* TSO (optional) */
102 struct {
103 u32 pkt_cnt;
104 u32 real_len;
105 };
106
107 u64 raw;
108 };
109 };
110
nfp_nfdk_headlen_to_segs(unsigned int headlen)111 static inline int nfp_nfdk_headlen_to_segs(unsigned int headlen)
112 {
113 /* First descriptor fits less data, so adjust for that */
114 return DIV_ROUND_UP(headlen +
115 NFDK_TX_MAX_DATA_PER_DESC -
116 NFDK_TX_MAX_DATA_PER_HEAD,
117 NFDK_TX_MAX_DATA_PER_DESC);
118 }
119
120 int nfp_nfdk_poll(struct napi_struct *napi, int budget);
121 netdev_tx_t nfp_nfdk_tx(struct sk_buff *skb, struct net_device *netdev);
122 bool
123 nfp_nfdk_ctrl_tx_one(struct nfp_net *nn, struct nfp_net_r_vector *r_vec,
124 struct sk_buff *skb, bool old);
125 void nfp_nfdk_ctrl_poll(struct tasklet_struct *t);
126 void nfp_nfdk_rx_ring_fill_freelist(struct nfp_net_dp *dp,
127 struct nfp_net_rx_ring *rx_ring);
128 #endif
129