xref: /freebsd/sys/dev/sfxge/sfxge_tx.h (revision bc96366c864c07ef352edb92017357917c75b36c)
1 /*-
2  * Copyright (c) 2010-2011 Solarflare Communications, Inc.
3  * All rights reserved.
4  *
5  * This software was developed in part by Philip Paeps under contract for
6  * Solarflare Communications, Inc.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  *
29  * $FreeBSD$
30  */
31 
32 #ifndef _SFXGE_TX_H
33 #define	_SFXGE_TX_H
34 
35 #include <netinet/in.h>
36 #include <netinet/ip.h>
37 #include <netinet/tcp.h>
38 
39 /* Maximum number of DMA segments needed to map an mbuf chain.  With
40  * TSO, the mbuf length may be just over 64K, divided into 2K mbuf
41  * clusters.  (The chain could be longer than this initially, but can
42  * be shortened with m_collapse().)
43  */
44 #define	SFXGE_TX_MAPPING_MAX_SEG (64 / 2 + 1)
45 
46 /* Maximum number of DMA segments needed to map an output packet.  It
47  * could overlap all mbufs in the chain and also require an extra
48  * segment for a TSO header.
49  */
50 #define	SFXGE_TX_PACKET_MAX_SEG (SFXGE_TX_MAPPING_MAX_SEG + 1)
51 
52 /*
53  * Buffer mapping flags.
54  *
55  * Buffers and DMA mappings must be freed when the last descriptor
56  * referring to them is completed.  Set the TX_BUF_UNMAP and
57  * TX_BUF_MBUF flags on the last descriptor generated for an mbuf
58  * chain.  Set only the TX_BUF_UNMAP flag on a descriptor referring to
59  * a heap buffer.
60  */
61 enum sfxge_tx_buf_flags {
62 	TX_BUF_UNMAP = 1,
63 	TX_BUF_MBUF = 2,
64 };
65 
66 /*
67  * Buffer mapping information for descriptors in flight.
68  */
69 struct sfxge_tx_mapping {
70 	union {
71 		struct mbuf	*mbuf;
72 		caddr_t		heap_buf;
73 	}			u;
74 	bus_dmamap_t		map;
75 	enum sfxge_tx_buf_flags	flags;
76 };
77 
78 #define	SFXGE_TX_DPL_GET_PKT_LIMIT_DEFAULT	1024
79 #define	SFXGE_TX_DPL_PUT_PKT_LIMIT_DEFAULT	64
80 
81 /*
82  * Deferred packet list.
83  */
84 struct sfxge_tx_dpl {
85 	unsigned int		std_get_max;	/* Maximum number of packets
86 						 * in get list */
87 	unsigned int		std_put_max;	/* Maximum number of packets
88 						 * in put list */
89 	uintptr_t		std_put;	/* Head of put list. */
90 	struct mbuf		*std_get;	/* Head of get list. */
91 	struct mbuf		**std_getp;	/* Tail of get list. */
92 	unsigned int		std_get_count;	/* Packets in get list. */
93 };
94 
95 
96 #define	SFXGE_TX_BUFFER_SIZE	0x400
97 #define	SFXGE_TX_HEADER_SIZE	0x100
98 #define	SFXGE_TX_COPY_THRESHOLD	0x200
99 
100 enum sfxge_txq_state {
101 	SFXGE_TXQ_UNINITIALIZED = 0,
102 	SFXGE_TXQ_INITIALIZED,
103 	SFXGE_TXQ_STARTED
104 };
105 
106 enum sfxge_txq_type {
107 	SFXGE_TXQ_NON_CKSUM = 0,
108 	SFXGE_TXQ_IP_CKSUM,
109 	SFXGE_TXQ_IP_TCP_UDP_CKSUM,
110 	SFXGE_TXQ_NTYPES
111 };
112 
113 #define	SFXGE_TXQ_UNBLOCK_LEVEL(_entries)	(EFX_TXQ_LIMIT(_entries) / 4)
114 
115 #define	SFXGE_TX_BATCH	64
116 
117 #ifdef SFXGE_HAVE_MQ
118 #define	SFXGE_TXQ_LOCK(txq)		(&(txq)->lock)
119 #define	SFXGE_TX_SCALE(sc)		((sc)->intr.n_alloc)
120 #else
121 #define	SFXGE_TXQ_LOCK(txq)		(&(txq)->sc->tx_lock)
122 #define	SFXGE_TX_SCALE(sc)		1
123 #endif
124 
125 struct sfxge_txq {
126 	/* The following fields should be written very rarely */
127 	struct sfxge_softc		*sc;
128 	enum sfxge_txq_state		init_state;
129 	enum sfxge_flush_state		flush_state;
130 	enum sfxge_txq_type		type;
131 	unsigned int			txq_index;
132 	unsigned int			evq_index;
133 	efsys_mem_t			mem;
134 	unsigned int			buf_base_id;
135 	unsigned int			entries;
136 	unsigned int			ptr_mask;
137 
138 	struct sfxge_tx_mapping		*stmp;	/* Packets in flight. */
139 	bus_dma_tag_t			packet_dma_tag;
140 	efx_buffer_t			*pend_desc;
141 	efx_txq_t			*common;
142 	struct sfxge_txq		*next;
143 
144 	efsys_mem_t			*tsoh_buffer;
145 
146 	/* This field changes more often and is read regularly on both
147 	 * the initiation and completion paths
148 	 */
149 	int				blocked __aligned(CACHE_LINE_SIZE);
150 
151 	/* The following fields change more often, and are used mostly
152 	 * on the initiation path
153 	 */
154 #ifdef SFXGE_HAVE_MQ
155 	struct mtx			lock __aligned(CACHE_LINE_SIZE);
156 	struct sfxge_tx_dpl		dpl;	/* Deferred packet list. */
157 	unsigned int			n_pend_desc;
158 #else
159 	unsigned int			n_pend_desc __aligned(CACHE_LINE_SIZE);
160 #endif
161 	unsigned int			added;
162 	unsigned int			reaped;
163 	/* Statistics */
164 	unsigned long			tso_bursts;
165 	unsigned long			tso_packets;
166 	unsigned long			tso_long_headers;
167 	unsigned long			collapses;
168 	unsigned long			drops;
169 	unsigned long			early_drops;
170 
171 	/* The following fields change more often, and are used mostly
172 	 * on the completion path
173 	 */
174 	unsigned int			pending __aligned(CACHE_LINE_SIZE);
175 	unsigned int			completed;
176 };
177 
178 extern int sfxge_tx_packet_add(struct sfxge_txq *, struct mbuf *);
179 
180 extern int sfxge_tx_init(struct sfxge_softc *sc);
181 extern void sfxge_tx_fini(struct sfxge_softc *sc);
182 extern int sfxge_tx_start(struct sfxge_softc *sc);
183 extern void sfxge_tx_stop(struct sfxge_softc *sc);
184 extern void sfxge_tx_qcomplete(struct sfxge_txq *txq);
185 extern void sfxge_tx_qflush_done(struct sfxge_txq *txq);
186 #ifdef SFXGE_HAVE_MQ
187 extern void sfxge_if_qflush(struct ifnet *ifp);
188 extern int sfxge_if_transmit(struct ifnet *ifp, struct mbuf *m);
189 #else
190 extern void sfxge_if_start(struct ifnet *ifp);
191 #endif
192 
193 #endif
194