Add the sfxge(4) device driver, providing support for 10Gb Ethernet adapters

based on Solarflare SFC9000 family controllers.  The driver supports jumbo
frames, transmit/receive checksum offload, TCP Segmentation Offload (TSO),
Large Receive Offload (LRO), VLAN checksum offload, VLAN TSO, and Receive Side
Scaling (RSS) using MSI-X interrupts.

This work was sponsored by Solarflare Communications, Inc.

My sincere thanks to Ben Hutchings for doing a lot of the hard work!

Sponsored by:	Solarflare Communications, Inc.
MFC after:	3 weeks

1 files changed, 185 insertions, 0 deletions

diff --git a/sys/dev/sfxge/sfxge_tx.h b/sys/dev/sfxge/sfxge_tx.h
new file mode 100644
index 0000000..483a16a
--- /dev/null
+++ b/sys/dev/sfxge/sfxge_tx.h
@@ -0,0 +1,185 @@
+/*-
+ * Copyright (c) 2010-2011 Solarflare Communications, Inc.
+ * All rights reserved.
+ *
+ * This software was developed in part by Philip Paeps under contract for
+ * Solarflare Communications, Inc.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * $FreeBSD$
+ */
+
+#ifndef _SFXGE_TX_H
+#define _SFXGE_TX_H
+
+#include <netinet/in.h>
+#include <netinet/ip.h>
+#include <netinet/tcp.h>
+
+/* Maximum number of DMA segments needed to map an mbuf chain.  With
+ * TSO, the mbuf length may be just over 64K, divided into 2K mbuf
+ * clusters.  (The chain could be longer than this initially, but can
+ * be shortened with m_collapse().)
+ */
+#define	SFXGE_TX_MAPPING_MAX_SEG (64 / 2 + 1)
+
+/* Maximum number of DMA segments needed to map an output packet.  It
+ * could overlap all mbufs in the chain and also require an extra
+ * segment for a TSO header.
+ */
+#define SFXGE_TX_PACKET_MAX_SEG (SFXGE_TX_MAPPING_MAX_SEG + 1)
+
+/*
+ * Buffer mapping flags.
+ *
+ * Buffers and DMA mappings must be freed when the last descriptor
+ * referring to them is completed.  Set the TX_BUF_UNMAP and
+ * TX_BUF_MBUF flags on the last descriptor generated for an mbuf
+ * chain.  Set only the TX_BUF_UNMAP flag on a descriptor referring to
+ * a heap buffer.
+ */
+enum sfxge_tx_buf_flags {
+	TX_BUF_UNMAP = 1,
+	TX_BUF_MBUF = 2,
+};
+
+/*
+ * Buffer mapping information for descriptors in flight.
+ */
+struct sfxge_tx_mapping {
+	union {
+		struct mbuf	*mbuf;
+		caddr_t		heap_buf;
+	}			u;
+	bus_dmamap_t		map;
+	enum sfxge_tx_buf_flags	flags;
+};
+
+#define SFXGE_TX_MAX_DEFERRED 64
+
+/*
+ * Deferred packet list.
+ */
+struct sfxge_tx_dpl {
+	uintptr_t		std_put;    /* Head of put list. */
+	struct mbuf		*std_get;   /* Head of get list. */
+	struct mbuf		**std_getp; /* Tail of get list. */
+	unsigned int		std_count;  /* Count of packets. */
+};
+
+
+#define	SFXGE_TX_BUFFER_SIZE	0x400
+#define	SFXGE_TX_HEADER_SIZE	0x100
+#define	SFXGE_TX_COPY_THRESHOLD	0x200
+
+enum sfxge_txq_state {
+	SFXGE_TXQ_UNINITIALIZED = 0,
+	SFXGE_TXQ_INITIALIZED,
+	SFXGE_TXQ_STARTED
+};
+
+enum sfxge_txq_type {
+	SFXGE_TXQ_NON_CKSUM = 0,
+	SFXGE_TXQ_IP_CKSUM,
+	SFXGE_TXQ_IP_TCP_UDP_CKSUM,
+	SFXGE_TXQ_NTYPES
+};
+
+#define	SFXGE_TXQ_UNBLOCK_LEVEL		(EFX_TXQ_LIMIT(SFXGE_NDESCS) / 4)
+
+#define	SFXGE_TX_BATCH	64
+
+#ifdef SFXGE_HAVE_MQ
+#define SFXGE_TXQ_LOCK(txq)		(&(txq)->lock)
+#define SFXGE_TX_SCALE(sc)		((sc)->intr.n_alloc)
+#else
+#define SFXGE_TXQ_LOCK(txq)		(&(txq)->sc->tx_lock)
+#define SFXGE_TX_SCALE(sc)		1
+#endif
+
+struct sfxge_txq {
+	/* The following fields should be written very rarely */
+	struct sfxge_softc		*sc;
+	enum sfxge_txq_state		init_state;
+	enum sfxge_flush_state		flush_state;
+	enum sfxge_txq_type		type;
+	unsigned int			txq_index;
+	unsigned int			evq_index;
+	efsys_mem_t			mem;
+	unsigned int			buf_base_id;
+
+	struct sfxge_tx_mapping		*stmp;	/* Packets in flight. */
+	bus_dma_tag_t			packet_dma_tag;
+	efx_buffer_t			*pend_desc;
+	efx_txq_t			*common;
+	struct sfxge_txq		*next;
+
+	efsys_mem_t			*tsoh_buffer;
+
+	/* This field changes more often and is read regularly on both
+	 * the initiation and completion paths
+	 */
+	int				blocked __aligned(CACHE_LINE_SIZE);
+
+	/* The following fields change more often, and are used mostly
+	 * on the initiation path
+	 */
+#ifdef SFXGE_HAVE_MQ
+	struct mtx			lock __aligned(CACHE_LINE_SIZE);
+	struct sfxge_tx_dpl		dpl;	/* Deferred packet list. */
+	unsigned int			n_pend_desc;
+#else
+	unsigned int			n_pend_desc __aligned(CACHE_LINE_SIZE);
+#endif
+	unsigned int			added;
+	unsigned int			reaped;
+	/* Statistics */
+	unsigned long			tso_bursts;
+	unsigned long			tso_packets;
+	unsigned long			tso_long_headers;
+	unsigned long			collapses;
+	unsigned long			drops;
+
+	/* The following fields change more often, and are used mostly
+	 * on the completion path
+	 */
+	unsigned int			pending __aligned(CACHE_LINE_SIZE);
+	unsigned int			completed;
+};
+
+extern int sfxge_tx_packet_add(struct sfxge_txq *, struct mbuf *);
+
+extern int sfxge_tx_init(struct sfxge_softc *sc);
+extern void sfxge_tx_fini(struct sfxge_softc *sc);
+extern int sfxge_tx_start(struct sfxge_softc *sc);
+extern void sfxge_tx_stop(struct sfxge_softc *sc);
+extern void sfxge_tx_qcomplete(struct sfxge_txq *txq);
+extern void sfxge_tx_qflush_done(struct sfxge_txq *txq);
+#ifdef SFXGE_HAVE_MQ
+extern void sfxge_if_qflush(struct ifnet *ifp);
+extern int sfxge_if_transmit(struct ifnet *ifp, struct mbuf *m);
+#else
+extern void sfxge_if_start(struct ifnet *ifp);
+#endif
+
+#endif