1 /*
2  * aQuantia Corporation Network Driver
3  * Copyright (C) 2014-2017 aQuantia Corporation. All rights reserved
4  *
5  * This program is free software; you can redistribute it and/or modify it
6  * under the terms and conditions of the GNU General Public License,
7  * version 2, as published by the Free Software Foundation.
8  */
9 
10 /* File aq_ring.h: Declaration of functions for Rx/Tx rings. */
11 
12 #ifndef AQ_RING_H
13 #define AQ_RING_H
14 
15 #include "aq_common.h"
16 
17 struct page;
18 
19 /*           TxC       SOP        DX         EOP
20  *         +----------+----------+----------+-----------
21  *   8bytes|len l3,l4 | pa       | pa       | pa
22  *         +----------+----------+----------+-----------
23  * 4/8bytes|len pkt   |len pkt   |          | skb
24  *         +----------+----------+----------+-----------
25  * 4/8bytes|is_txc    |len,flags |len       |len,is_eop
26  *         +----------+----------+----------+-----------
27  *
28  *  This aq_ring_buff_s doesn't have endianness dependency.
29  *  It is __packed for cache line optimizations.
30  */
31 struct __packed aq_ring_buff_s {
32 	union {
33 		/* RX */
34 		struct {
35 			u32 rss_hash;
36 			u16 next;
37 			u8 is_hash_l4;
38 			u8 rsvd1;
39 			struct page *page;
40 		};
41 		/* EOP */
42 		struct {
43 			dma_addr_t pa_eop;
44 			struct sk_buff *skb;
45 		};
46 		/* DX */
47 		struct {
48 			dma_addr_t pa;
49 		};
50 		/* SOP */
51 		struct {
52 			dma_addr_t pa_sop;
53 			u32 len_pkt_sop;
54 		};
55 		/* TxC */
56 		struct {
57 			u32 mss;
58 			u8 len_l2;
59 			u8 len_l3;
60 			u8 len_l4;
61 			u8 is_ipv6:1;
62 			u8 rsvd2:7;
63 			u32 len_pkt;
64 		};
65 	};
66 	union {
67 		struct {
68 			u32 len:16;
69 			u32 is_ip_cso:1;
70 			u32 is_udp_cso:1;
71 			u32 is_tcp_cso:1;
72 			u32 is_cso_err:1;
73 			u32 is_sop:1;
74 			u32 is_eop:1;
75 			u32 is_txc:1;
76 			u32 is_mapped:1;
77 			u32 is_cleaned:1;
78 			u32 is_error:1;
79 			u32 rsvd3:6;
80 		};
81 		u32 flags;
82 	};
83 };
84 
85 struct aq_ring_stats_rx_s {
86 	u64 errors;
87 	u64 packets;
88 	u64 bytes;
89 	u64 lro_packets;
90 	u64 jumbo_packets;
91 };
92 
93 struct aq_ring_stats_tx_s {
94 	u64 errors;
95 	u64 packets;
96 	u64 bytes;
97 };
98 
99 union aq_ring_stats_s {
100 	struct aq_ring_stats_rx_s rx;
101 	struct aq_ring_stats_tx_s tx;
102 };
103 
104 struct aq_ring_s {
105 	struct aq_obj_s header;
106 	struct aq_ring_buff_s *buff_ring;
107 	u8 *dx_ring;		/* descriptors ring, dma shared mem */
108 	struct aq_nic_s *aq_nic;
109 	unsigned int idx;	/* for HW layer registers operations */
110 	unsigned int hw_head;
111 	unsigned int sw_head;
112 	unsigned int sw_tail;
113 	unsigned int size;	/* descriptors number */
114 	unsigned int dx_size;	/* TX or RX descriptor size,  */
115 				/* stored here for fater math */
116 	union aq_ring_stats_s stats;
117 	dma_addr_t dx_ring_pa;
118 };
119 
120 struct aq_ring_param_s {
121 	unsigned int vec_idx;
122 	unsigned int cpu;
123 	cpumask_t affinity_mask;
124 };
125 
126 static inline unsigned int aq_ring_next_dx(struct aq_ring_s *self,
127 					   unsigned int dx)
128 {
129 	return (++dx >= self->size) ? 0U : dx;
130 }
131 
132 static inline unsigned int aq_ring_avail_dx(struct aq_ring_s *self)
133 {
134 	return (((self->sw_tail >= self->sw_head)) ?
135 		(self->size - 1) - self->sw_tail + self->sw_head :
136 		self->sw_head - self->sw_tail - 1);
137 }
138 
139 struct aq_ring_s *aq_ring_tx_alloc(struct aq_ring_s *self,
140 				   struct aq_nic_s *aq_nic,
141 				   unsigned int idx,
142 				   struct aq_nic_cfg_s *aq_nic_cfg);
143 struct aq_ring_s *aq_ring_rx_alloc(struct aq_ring_s *self,
144 				   struct aq_nic_s *aq_nic,
145 				   unsigned int idx,
146 				   struct aq_nic_cfg_s *aq_nic_cfg);
147 int aq_ring_init(struct aq_ring_s *self);
148 void aq_ring_rx_deinit(struct aq_ring_s *self);
149 void aq_ring_free(struct aq_ring_s *self);
150 void aq_ring_tx_clean(struct aq_ring_s *self);
151 int aq_ring_rx_clean(struct aq_ring_s *self, int *work_done, int budget);
152 int aq_ring_rx_fill(struct aq_ring_s *self);
153 
154 #endif /* AQ_RING_H */
155