xref: /linux/drivers/net/ethernet/meta/fbnic/fbnic_txrx.h (revision 3fd6c59042dbba50391e30862beac979491145fe)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /* Copyright (c) Meta Platforms, Inc. and affiliates. */
3 
4 #ifndef _FBNIC_TXRX_H_
5 #define _FBNIC_TXRX_H_
6 
7 #include <linux/netdevice.h>
8 #include <linux/skbuff.h>
9 #include <linux/types.h>
10 #include <linux/u64_stats_sync.h>
11 #include <net/xdp.h>
12 
13 struct fbnic_net;
14 
15 /* Guarantee we have space needed for storing the buffer
16  * To store the buffer we need:
17  *	1 descriptor per page
18  *	+ 1 descriptor for skb head
19  *	+ 2 descriptors for metadata and optional metadata
20  *	+ 7 descriptors to keep tail out of the same cacheline as head
21  * If we cannot guarantee that then we should return TX_BUSY
22  */
23 #define FBNIC_MAX_SKB_DESC	(MAX_SKB_FRAGS + 10)
24 #define FBNIC_TX_DESC_WAKEUP	(FBNIC_MAX_SKB_DESC * 2)
25 #define FBNIC_TX_DESC_MIN	roundup_pow_of_two(FBNIC_TX_DESC_WAKEUP)
26 
27 #define FBNIC_MAX_TXQS			128u
28 #define FBNIC_MAX_RXQS			128u
29 
30 #define FBNIC_TXQ_SIZE_DEFAULT		1024
31 #define FBNIC_HPQ_SIZE_DEFAULT		256
32 #define FBNIC_PPQ_SIZE_DEFAULT		256
33 #define FBNIC_RCQ_SIZE_DEFAULT		1024
34 
35 #define FBNIC_RX_TROOM \
36 	SKB_DATA_ALIGN(sizeof(struct skb_shared_info))
37 #define FBNIC_RX_HROOM \
38 	(ALIGN(FBNIC_RX_TROOM + NET_SKB_PAD, 128) - FBNIC_RX_TROOM)
39 #define FBNIC_RX_PAD			0
40 #define FBNIC_RX_MAX_HDR		(1536 - FBNIC_RX_PAD)
41 #define FBNIC_RX_PAYLD_OFFSET		0
42 #define FBNIC_RX_PAYLD_PG_CL		0
43 
44 #define FBNIC_RING_F_DISABLED		BIT(0)
45 #define FBNIC_RING_F_CTX		BIT(1)
46 #define FBNIC_RING_F_STATS		BIT(2)	/* Ring's stats may be used */
47 
48 struct fbnic_pkt_buff {
49 	struct xdp_buff buff;
50 	ktime_t hwtstamp;
51 	u32 data_truesize;
52 	u16 data_len;
53 	u16 nr_frags;
54 };
55 
56 struct fbnic_queue_stats {
57 	u64 packets;
58 	u64 bytes;
59 	u64 dropped;
60 	u64 ts_packets;
61 	u64 ts_lost;
62 	struct u64_stats_sync syncp;
63 };
64 
65 /* Pagecnt bias is long max to reserve the last bit to catch overflow
66  * cases where if we overcharge the bias it will flip over to be negative.
67  */
68 #define PAGECNT_BIAS_MAX	LONG_MAX
69 struct fbnic_rx_buf {
70 	struct page *page;
71 	long pagecnt_bias;
72 };
73 
74 struct fbnic_ring {
75 	/* Pointer to buffer specific info */
76 	union {
77 		struct fbnic_pkt_buff *pkt;	/* RCQ */
78 		struct fbnic_rx_buf *rx_buf;	/* BDQ */
79 		void **tx_buf;			/* TWQ */
80 		void *buffer;			/* Generic pointer */
81 	};
82 
83 	u32 __iomem *doorbell;		/* Pointer to CSR space for ring */
84 	__le64 *desc;			/* Descriptor ring memory */
85 	u16 size_mask;			/* Size of ring in descriptors - 1 */
86 	u8 q_idx;			/* Logical netdev ring index */
87 	u8 flags;			/* Ring flags (FBNIC_RING_F_*) */
88 
89 	u32 head, tail;			/* Head/Tail of ring */
90 
91 	struct fbnic_queue_stats stats;
92 
93 	/* Slow path fields follow */
94 	dma_addr_t dma;			/* Phys addr of descriptor memory */
95 	size_t size;			/* Size of descriptor ring in memory */
96 };
97 
98 struct fbnic_q_triad {
99 	struct fbnic_ring sub0, sub1, cmpl;
100 };
101 
102 struct fbnic_napi_vector {
103 	struct napi_struct napi;
104 	struct device *dev;		/* Device for DMA unmapping */
105 	struct page_pool *page_pool;
106 	struct fbnic_dev *fbd;
107 	char name[IFNAMSIZ + 9];
108 
109 	u16 v_idx;
110 	u8 txt_count;
111 	u8 rxt_count;
112 
113 	struct list_head napis;
114 
115 	struct fbnic_q_triad qt[];
116 };
117 
118 #define FBNIC_MAX_TXQS			128u
119 #define FBNIC_MAX_RXQS			128u
120 
121 netdev_tx_t fbnic_xmit_frame(struct sk_buff *skb, struct net_device *dev);
122 netdev_features_t
123 fbnic_features_check(struct sk_buff *skb, struct net_device *dev,
124 		     netdev_features_t features);
125 
126 int fbnic_alloc_napi_vectors(struct fbnic_net *fbn);
127 void fbnic_free_napi_vectors(struct fbnic_net *fbn);
128 int fbnic_alloc_resources(struct fbnic_net *fbn);
129 void fbnic_free_resources(struct fbnic_net *fbn);
130 void fbnic_napi_enable(struct fbnic_net *fbn);
131 void fbnic_napi_disable(struct fbnic_net *fbn);
132 void fbnic_enable(struct fbnic_net *fbn);
133 void fbnic_disable(struct fbnic_net *fbn);
134 void fbnic_flush(struct fbnic_net *fbn);
135 void fbnic_fill(struct fbnic_net *fbn);
136 
137 void fbnic_napi_depletion_check(struct net_device *netdev);
138 int fbnic_wait_all_queues_idle(struct fbnic_dev *fbd, bool may_fail);
139 
140 #endif /* _FBNIC_TXRX_H_ */
141