xref: /linux/drivers/net/ethernet/meta/fbnic/fbnic_txrx.h (revision 1a9239bb4253f9076b5b4b2a1a4e8d7defd77a95)
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 /* To receive the worst case packet we need:
28  *	1 descriptor for primary metadata
29  *	+ 1 descriptor for optional metadata
30  *	+ 1 descriptor for headers
31  *	+ 4 descriptors for payload
32  */
33 #define FBNIC_MAX_RX_PKT_DESC	7
34 #define FBNIC_RX_DESC_MIN	roundup_pow_of_two(FBNIC_MAX_RX_PKT_DESC * 2)
35 
36 #define FBNIC_MAX_TXQS			128u
37 #define FBNIC_MAX_RXQS			128u
38 
39 /* These apply to TWQs, TCQ, RCQ */
40 #define FBNIC_QUEUE_SIZE_MIN		16u
41 #define FBNIC_QUEUE_SIZE_MAX		SZ_64K
42 
43 #define FBNIC_TXQ_SIZE_DEFAULT		1024
44 #define FBNIC_HPQ_SIZE_DEFAULT		256
45 #define FBNIC_PPQ_SIZE_DEFAULT		256
46 #define FBNIC_RCQ_SIZE_DEFAULT		1024
47 #define FBNIC_TX_USECS_DEFAULT		35
48 #define FBNIC_RX_USECS_DEFAULT		30
49 #define FBNIC_RX_FRAMES_DEFAULT		0
50 
51 #define FBNIC_RX_TROOM \
52 	SKB_DATA_ALIGN(sizeof(struct skb_shared_info))
53 #define FBNIC_RX_HROOM \
54 	(ALIGN(FBNIC_RX_TROOM + NET_SKB_PAD, 128) - FBNIC_RX_TROOM)
55 #define FBNIC_RX_PAD			0
56 #define FBNIC_RX_MAX_HDR		(1536 - FBNIC_RX_PAD)
57 #define FBNIC_RX_PAYLD_OFFSET		0
58 #define FBNIC_RX_PAYLD_PG_CL		0
59 
60 #define FBNIC_RING_F_DISABLED		BIT(0)
61 #define FBNIC_RING_F_CTX		BIT(1)
62 #define FBNIC_RING_F_STATS		BIT(2)	/* Ring's stats may be used */
63 
64 struct fbnic_pkt_buff {
65 	struct xdp_buff buff;
66 	ktime_t hwtstamp;
67 	u32 data_truesize;
68 	u16 data_len;
69 	u16 nr_frags;
70 };
71 
72 struct fbnic_queue_stats {
73 	u64 packets;
74 	u64 bytes;
75 	union {
76 		struct {
77 			u64 csum_partial;
78 			u64 lso;
79 			u64 ts_packets;
80 			u64 ts_lost;
81 			u64 stop;
82 			u64 wake;
83 		} twq;
84 		struct {
85 			u64 alloc_failed;
86 			u64 csum_complete;
87 			u64 csum_none;
88 		} rx;
89 	};
90 	u64 dropped;
91 	struct u64_stats_sync syncp;
92 };
93 
94 /* Pagecnt bias is long max to reserve the last bit to catch overflow
95  * cases where if we overcharge the bias it will flip over to be negative.
96  */
97 #define PAGECNT_BIAS_MAX	LONG_MAX
98 struct fbnic_rx_buf {
99 	struct page *page;
100 	long pagecnt_bias;
101 };
102 
103 struct fbnic_ring {
104 	/* Pointer to buffer specific info */
105 	union {
106 		struct fbnic_pkt_buff *pkt;	/* RCQ */
107 		struct fbnic_rx_buf *rx_buf;	/* BDQ */
108 		void **tx_buf;			/* TWQ */
109 		void *buffer;			/* Generic pointer */
110 	};
111 
112 	u32 __iomem *doorbell;		/* Pointer to CSR space for ring */
113 	__le64 *desc;			/* Descriptor ring memory */
114 	u16 size_mask;			/* Size of ring in descriptors - 1 */
115 	u8 q_idx;			/* Logical netdev ring index */
116 	u8 flags;			/* Ring flags (FBNIC_RING_F_*) */
117 
118 	u32 head, tail;			/* Head/Tail of ring */
119 
120 	struct fbnic_queue_stats stats;
121 
122 	/* Slow path fields follow */
123 	dma_addr_t dma;			/* Phys addr of descriptor memory */
124 	size_t size;			/* Size of descriptor ring in memory */
125 };
126 
127 struct fbnic_q_triad {
128 	struct fbnic_ring sub0, sub1, cmpl;
129 };
130 
131 struct fbnic_napi_vector {
132 	struct napi_struct napi;
133 	struct device *dev;		/* Device for DMA unmapping */
134 	struct page_pool *page_pool;
135 	struct fbnic_dev *fbd;
136 
137 	u16 v_idx;
138 	u8 txt_count;
139 	u8 rxt_count;
140 
141 	struct fbnic_q_triad qt[];
142 };
143 
144 #define FBNIC_MAX_TXQS			128u
145 #define FBNIC_MAX_RXQS			128u
146 
147 netdev_tx_t fbnic_xmit_frame(struct sk_buff *skb, struct net_device *dev);
148 netdev_features_t
149 fbnic_features_check(struct sk_buff *skb, struct net_device *dev,
150 		     netdev_features_t features);
151 
152 void fbnic_aggregate_ring_rx_counters(struct fbnic_net *fbn,
153 				      struct fbnic_ring *rxr);
154 void fbnic_aggregate_ring_tx_counters(struct fbnic_net *fbn,
155 				      struct fbnic_ring *txr);
156 
157 int fbnic_alloc_napi_vectors(struct fbnic_net *fbn);
158 void fbnic_free_napi_vectors(struct fbnic_net *fbn);
159 int fbnic_alloc_resources(struct fbnic_net *fbn);
160 void fbnic_free_resources(struct fbnic_net *fbn);
161 int fbnic_set_netif_queues(struct fbnic_net *fbn);
162 void fbnic_reset_netif_queues(struct fbnic_net *fbn);
163 irqreturn_t fbnic_msix_clean_rings(int irq, void *data);
164 void fbnic_napi_enable(struct fbnic_net *fbn);
165 void fbnic_napi_disable(struct fbnic_net *fbn);
166 void fbnic_enable(struct fbnic_net *fbn);
167 void fbnic_disable(struct fbnic_net *fbn);
168 void fbnic_flush(struct fbnic_net *fbn);
169 void fbnic_fill(struct fbnic_net *fbn);
170 
171 void fbnic_napi_depletion_check(struct net_device *netdev);
172 int fbnic_wait_all_queues_idle(struct fbnic_dev *fbd, bool may_fail);
173 
fbnic_napi_idx(const struct fbnic_napi_vector * nv)174 static inline int fbnic_napi_idx(const struct fbnic_napi_vector *nv)
175 {
176 	return nv->v_idx - FBNIC_NON_NAPI_VECTORS;
177 }
178 
179 #endif /* _FBNIC_TXRX_H_ */
180