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 struct aq_nic_cfg_s;
19 
20 /*           TxC       SOP        DX         EOP
21  *         +----------+----------+----------+-----------
22  *   8bytes|len l3,l4 | pa       | pa       | pa
23  *         +----------+----------+----------+-----------
24  * 4/8bytes|len pkt   |len pkt   |          | skb
25  *         +----------+----------+----------+-----------
26  * 4/8bytes|is_txc    |len,flags |len       |len,is_eop
27  *         +----------+----------+----------+-----------
28  *
29  *  This aq_ring_buff_s doesn't have endianness dependency.
30  *  It is __packed for cache line optimizations.
31  */
32 struct __packed aq_ring_buff_s {
33 	union {
34 		/* RX */
35 		struct {
36 			u32 rss_hash;
37 			u16 next;
38 			u8 is_hash_l4;
39 			u8 rsvd1;
40 			struct page *page;
41 		};
42 		/* EOP */
43 		struct {
44 			dma_addr_t pa_eop;
45 			struct sk_buff *skb;
46 		};
47 		/* DX */
48 		struct {
49 			dma_addr_t pa;
50 		};
51 		/* SOP */
52 		struct {
53 			dma_addr_t pa_sop;
54 			u32 len_pkt_sop;
55 		};
56 		/* TxC */
57 		struct {
58 			u32 mss;
59 			u8 len_l2;
60 			u8 len_l3;
61 			u8 len_l4;
62 			u8 is_ipv6:1;
63 			u8 rsvd2:7;
64 			u32 len_pkt;
65 		};
66 	};
67 	union {
68 		struct {
69 			u16 len;
70 			u32 is_ip_cso:1;
71 			u32 is_udp_cso:1;
72 			u32 is_tcp_cso:1;
73 			u32 is_cso_err:1;
74 			u32 is_sop:1;
75 			u32 is_eop:1;
76 			u32 is_txc:1;
77 			u32 is_mapped:1;
78 			u32 is_cleaned:1;
79 			u32 is_error:1;
80 			u32 rsvd3:6;
81 			u16 eop_index;
82 			u16 rsvd4;
83 		};
84 		u64 flags;
85 	};
86 };
87 
88 struct aq_ring_stats_rx_s {
89 	u64 errors;
90 	u64 packets;
91 	u64 bytes;
92 	u64 lro_packets;
93 	u64 jumbo_packets;
94 };
95 
96 struct aq_ring_stats_tx_s {
97 	u64 errors;
98 	u64 packets;
99 	u64 bytes;
100 	u64 queue_restarts;
101 };
102 
103 union aq_ring_stats_s {
104 	struct aq_ring_stats_rx_s rx;
105 	struct aq_ring_stats_tx_s tx;
106 };
107 
108 struct aq_ring_s {
109 	struct aq_ring_buff_s *buff_ring;
110 	u8 *dx_ring;		/* descriptors ring, dma shared mem */
111 	struct aq_nic_s *aq_nic;
112 	unsigned int idx;	/* for HW layer registers operations */
113 	unsigned int hw_head;
114 	unsigned int sw_head;
115 	unsigned int sw_tail;
116 	unsigned int size;	/* descriptors number */
117 	unsigned int dx_size;	/* TX or RX descriptor size,  */
118 				/* stored here for fater math */
119 	union aq_ring_stats_s stats;
120 	dma_addr_t dx_ring_pa;
121 };
122 
123 struct aq_ring_param_s {
124 	unsigned int vec_idx;
125 	unsigned int cpu;
126 	cpumask_t affinity_mask;
127 };
128 
129 static inline unsigned int aq_ring_next_dx(struct aq_ring_s *self,
130 					   unsigned int dx)
131 {
132 	return (++dx >= self->size) ? 0U : dx;
133 }
134 
135 static inline unsigned int aq_ring_avail_dx(struct aq_ring_s *self)
136 {
137 	return (((self->sw_tail >= self->sw_head)) ?
138 		(self->size - 1) - self->sw_tail + self->sw_head :
139 		self->sw_head - self->sw_tail - 1);
140 }
141 
142 struct aq_ring_s *aq_ring_tx_alloc(struct aq_ring_s *self,
143 				   struct aq_nic_s *aq_nic,
144 				   unsigned int idx,
145 				   struct aq_nic_cfg_s *aq_nic_cfg);
146 struct aq_ring_s *aq_ring_rx_alloc(struct aq_ring_s *self,
147 				   struct aq_nic_s *aq_nic,
148 				   unsigned int idx,
149 				   struct aq_nic_cfg_s *aq_nic_cfg);
150 int aq_ring_init(struct aq_ring_s *self);
151 void aq_ring_rx_deinit(struct aq_ring_s *self);
152 void aq_ring_free(struct aq_ring_s *self);
153 void aq_ring_update_queue_state(struct aq_ring_s *ring);
154 void aq_ring_queue_wake(struct aq_ring_s *ring);
155 void aq_ring_queue_stop(struct aq_ring_s *ring);
156 bool aq_ring_tx_clean(struct aq_ring_s *self);
157 int aq_ring_rx_clean(struct aq_ring_s *self,
158 		     struct napi_struct *napi,
159 		     int *work_done,
160 		     int budget);
161 int aq_ring_rx_fill(struct aq_ring_s *self);
162 
163 #endif /* AQ_RING_H */
164