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 */
61enum 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 */
69struct 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_MAX_DEFERRED 64
79
80/*
81 * Deferred packet list.
82 */
83struct sfxge_tx_dpl {
84	uintptr_t		std_put;    /* Head of put list. */
85	struct mbuf		*std_get;   /* Head of get list. */
86	struct mbuf		**std_getp; /* Tail of get list. */
87	unsigned int		std_count;  /* Count of packets. */
88};
89
90
91#define	SFXGE_TX_BUFFER_SIZE	0x400
92#define	SFXGE_TX_HEADER_SIZE	0x100
93#define	SFXGE_TX_COPY_THRESHOLD	0x200
94
95enum sfxge_txq_state {
96	SFXGE_TXQ_UNINITIALIZED = 0,
97	SFXGE_TXQ_INITIALIZED,
98	SFXGE_TXQ_STARTED
99};
100
101enum sfxge_txq_type {
102	SFXGE_TXQ_NON_CKSUM = 0,
103	SFXGE_TXQ_IP_CKSUM,
104	SFXGE_TXQ_IP_TCP_UDP_CKSUM,
105	SFXGE_TXQ_NTYPES
106};
107
108#define	SFXGE_TXQ_UNBLOCK_LEVEL		(EFX_TXQ_LIMIT(SFXGE_NDESCS) / 4)
109
110#define	SFXGE_TX_BATCH	64
111
112#ifdef SFXGE_HAVE_MQ
113#define SFXGE_TXQ_LOCK(txq)		(&(txq)->lock)
114#define SFXGE_TX_SCALE(sc)		((sc)->intr.n_alloc)
115#else
116#define SFXGE_TXQ_LOCK(txq)		(&(txq)->sc->tx_lock)
117#define SFXGE_TX_SCALE(sc)		1
118#endif
119
120struct sfxge_txq {
121	/* The following fields should be written very rarely */
122	struct sfxge_softc		*sc;
123	enum sfxge_txq_state		init_state;
124	enum sfxge_flush_state		flush_state;
125	enum sfxge_txq_type		type;
126	unsigned int			txq_index;
127	unsigned int			evq_index;
128	efsys_mem_t			mem;
129	unsigned int			buf_base_id;
130
131	struct sfxge_tx_mapping		*stmp;	/* Packets in flight. */
132	bus_dma_tag_t			packet_dma_tag;
133	efx_buffer_t			*pend_desc;
134	efx_txq_t			*common;
135	struct sfxge_txq		*next;
136
137	efsys_mem_t			*tsoh_buffer;
138
139	/* This field changes more often and is read regularly on both
140	 * the initiation and completion paths
141	 */
142	int				blocked __aligned(CACHE_LINE_SIZE);
143
144	/* The following fields change more often, and are used mostly
145	 * on the initiation path
146	 */
147#ifdef SFXGE_HAVE_MQ
148	struct mtx			lock __aligned(CACHE_LINE_SIZE);
149	struct sfxge_tx_dpl		dpl;	/* Deferred packet list. */
150	unsigned int			n_pend_desc;
151#else
152	unsigned int			n_pend_desc __aligned(CACHE_LINE_SIZE);
153#endif
154	unsigned int			added;
155	unsigned int			reaped;
156	/* Statistics */
157	unsigned long			tso_bursts;
158	unsigned long			tso_packets;
159	unsigned long			tso_long_headers;
160	unsigned long			collapses;
161	unsigned long			drops;
162
163	/* The following fields change more often, and are used mostly
164	 * on the completion path
165	 */
166	unsigned int			pending __aligned(CACHE_LINE_SIZE);
167	unsigned int			completed;
168};
169
170extern int sfxge_tx_packet_add(struct sfxge_txq *, struct mbuf *);
171
172extern int sfxge_tx_init(struct sfxge_softc *sc);
173extern void sfxge_tx_fini(struct sfxge_softc *sc);
174extern int sfxge_tx_start(struct sfxge_softc *sc);
175extern void sfxge_tx_stop(struct sfxge_softc *sc);
176extern void sfxge_tx_qcomplete(struct sfxge_txq *txq);
177extern void sfxge_tx_qflush_done(struct sfxge_txq *txq);
178#ifdef SFXGE_HAVE_MQ
179extern void sfxge_if_qflush(struct ifnet *ifp);
180extern int sfxge_if_transmit(struct ifnet *ifp, struct mbuf *m);
181#else
182extern void sfxge_if_start(struct ifnet *ifp);
183#endif
184
185#endif
186