IB/hfi1: Move driver out of staging

The TODO list for the hfi1 driver was completed during 4.6. In addition
other objections raised (which are far beyond what was in the TODO list)
have been addressed as well. It is now time to remove the driver from
staging and into the drivers/infiniband sub-tree.

Reviewed-by: Jubin John <jubin.john@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

1 files changed, 1082 insertions, 0 deletions

diff --git a/drivers/infiniband/hw/hfi1/sdma.h b/drivers/infiniband/hw/hfi1/sdma.h
new file mode 100644
index 000000000000..8f50c99fe711
--- /dev/null
+++ b/drivers/infiniband/hw/hfi1/sdma.h
@@ -0,0 +1,1082 @@
+#ifndef _HFI1_SDMA_H
+#define _HFI1_SDMA_H
+/*
+ * Copyright(c) 2015, 2016 Intel Corporation.
+ *
+ * This file is provided under a dual BSD/GPLv2 license.  When using or
+ * redistributing this file, you may do so under either license.
+ *
+ * GPL LICENSE SUMMARY
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * BSD LICENSE
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ *  - Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  - 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.
+ *  - Neither the name of Intel Corporation nor the names of its
+ *    contributors may be used to endorse or promote products derived
+ *    from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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 COPYRIGHT
+ * OWNER 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.
+ *
+ */
+
+#include <linux/types.h>
+#include <linux/list.h>
+#include <asm/byteorder.h>
+#include <linux/workqueue.h>
+#include <linux/rculist.h>
+
+#include "hfi.h"
+#include "verbs.h"
+#include "sdma_txreq.h"
+
+/* Hardware limit */
+#define MAX_DESC 64
+/* Hardware limit for SDMA packet size */
+#define MAX_SDMA_PKT_SIZE ((16 * 1024) - 1)
+
+#define SDMA_TXREQ_S_OK        0
+#define SDMA_TXREQ_S_SENDERROR 1
+#define SDMA_TXREQ_S_ABORTED   2
+#define SDMA_TXREQ_S_SHUTDOWN  3
+
+/* flags bits */
+#define SDMA_TXREQ_F_URGENT       0x0001
+#define SDMA_TXREQ_F_AHG_COPY     0x0002
+#define SDMA_TXREQ_F_USE_AHG      0x0004
+
+#define SDMA_MAP_NONE          0
+#define SDMA_MAP_SINGLE        1
+#define SDMA_MAP_PAGE          2
+
+#define SDMA_AHG_VALUE_MASK          0xffff
+#define SDMA_AHG_VALUE_SHIFT         0
+#define SDMA_AHG_INDEX_MASK          0xf
+#define SDMA_AHG_INDEX_SHIFT         16
+#define SDMA_AHG_FIELD_LEN_MASK      0xf
+#define SDMA_AHG_FIELD_LEN_SHIFT     20
+#define SDMA_AHG_FIELD_START_MASK    0x1f
+#define SDMA_AHG_FIELD_START_SHIFT   24
+#define SDMA_AHG_UPDATE_ENABLE_MASK  0x1
+#define SDMA_AHG_UPDATE_ENABLE_SHIFT 31
+
+/* AHG modes */
+
+/*
+ * Be aware the ordering and values
+ * for SDMA_AHG_APPLY_UPDATE[123]
+ * are assumed in generating a skip
+ * count in submit_tx() in sdma.c
+ */
+#define SDMA_AHG_NO_AHG              0
+#define SDMA_AHG_COPY                1
+#define SDMA_AHG_APPLY_UPDATE1       2
+#define SDMA_AHG_APPLY_UPDATE2       3
+#define SDMA_AHG_APPLY_UPDATE3       4
+
+/*
+ * Bits defined in the send DMA descriptor.
+ */
+#define SDMA_DESC0_FIRST_DESC_FLAG      BIT_ULL(63)
+#define SDMA_DESC0_LAST_DESC_FLAG       BIT_ULL(62)
+#define SDMA_DESC0_BYTE_COUNT_SHIFT     48
+#define SDMA_DESC0_BYTE_COUNT_WIDTH     14
+#define SDMA_DESC0_BYTE_COUNT_MASK \
+	((1ULL << SDMA_DESC0_BYTE_COUNT_WIDTH) - 1)
+#define SDMA_DESC0_BYTE_COUNT_SMASK \
+	(SDMA_DESC0_BYTE_COUNT_MASK << SDMA_DESC0_BYTE_COUNT_SHIFT)
+#define SDMA_DESC0_PHY_ADDR_SHIFT       0
+#define SDMA_DESC0_PHY_ADDR_WIDTH       48
+#define SDMA_DESC0_PHY_ADDR_MASK \
+	((1ULL << SDMA_DESC0_PHY_ADDR_WIDTH) - 1)
+#define SDMA_DESC0_PHY_ADDR_SMASK \
+	(SDMA_DESC0_PHY_ADDR_MASK << SDMA_DESC0_PHY_ADDR_SHIFT)
+
+#define SDMA_DESC1_HEADER_UPDATE1_SHIFT 32
+#define SDMA_DESC1_HEADER_UPDATE1_WIDTH 32
+#define SDMA_DESC1_HEADER_UPDATE1_MASK \
+	((1ULL << SDMA_DESC1_HEADER_UPDATE1_WIDTH) - 1)
+#define SDMA_DESC1_HEADER_UPDATE1_SMASK \
+	(SDMA_DESC1_HEADER_UPDATE1_MASK << SDMA_DESC1_HEADER_UPDATE1_SHIFT)
+#define SDMA_DESC1_HEADER_MODE_SHIFT    13
+#define SDMA_DESC1_HEADER_MODE_WIDTH    3
+#define SDMA_DESC1_HEADER_MODE_MASK \
+	((1ULL << SDMA_DESC1_HEADER_MODE_WIDTH) - 1)
+#define SDMA_DESC1_HEADER_MODE_SMASK \
+	(SDMA_DESC1_HEADER_MODE_MASK << SDMA_DESC1_HEADER_MODE_SHIFT)
+#define SDMA_DESC1_HEADER_INDEX_SHIFT   8
+#define SDMA_DESC1_HEADER_INDEX_WIDTH   5
+#define SDMA_DESC1_HEADER_INDEX_MASK \
+	((1ULL << SDMA_DESC1_HEADER_INDEX_WIDTH) - 1)
+#define SDMA_DESC1_HEADER_INDEX_SMASK \
+	(SDMA_DESC1_HEADER_INDEX_MASK << SDMA_DESC1_HEADER_INDEX_SHIFT)
+#define SDMA_DESC1_HEADER_DWS_SHIFT     4
+#define SDMA_DESC1_HEADER_DWS_WIDTH     4
+#define SDMA_DESC1_HEADER_DWS_MASK \
+	((1ULL << SDMA_DESC1_HEADER_DWS_WIDTH) - 1)
+#define SDMA_DESC1_HEADER_DWS_SMASK \
+	(SDMA_DESC1_HEADER_DWS_MASK << SDMA_DESC1_HEADER_DWS_SHIFT)
+#define SDMA_DESC1_GENERATION_SHIFT     2
+#define SDMA_DESC1_GENERATION_WIDTH     2
+#define SDMA_DESC1_GENERATION_MASK \
+	((1ULL << SDMA_DESC1_GENERATION_WIDTH) - 1)
+#define SDMA_DESC1_GENERATION_SMASK \
+	(SDMA_DESC1_GENERATION_MASK << SDMA_DESC1_GENERATION_SHIFT)
+#define SDMA_DESC1_INT_REQ_FLAG         BIT_ULL(1)
+#define SDMA_DESC1_HEAD_TO_HOST_FLAG    BIT_ULL(0)
+
+enum sdma_states {
+	sdma_state_s00_hw_down,
+	sdma_state_s10_hw_start_up_halt_wait,
+	sdma_state_s15_hw_start_up_clean_wait,
+	sdma_state_s20_idle,
+	sdma_state_s30_sw_clean_up_wait,
+	sdma_state_s40_hw_clean_up_wait,
+	sdma_state_s50_hw_halt_wait,
+	sdma_state_s60_idle_halt_wait,
+	sdma_state_s80_hw_freeze,
+	sdma_state_s82_freeze_sw_clean,
+	sdma_state_s99_running,
+};
+
+enum sdma_events {
+	sdma_event_e00_go_hw_down,
+	sdma_event_e10_go_hw_start,
+	sdma_event_e15_hw_halt_done,
+	sdma_event_e25_hw_clean_up_done,
+	sdma_event_e30_go_running,
+	sdma_event_e40_sw_cleaned,
+	sdma_event_e50_hw_cleaned,
+	sdma_event_e60_hw_halted,
+	sdma_event_e70_go_idle,
+	sdma_event_e80_hw_freeze,
+	sdma_event_e81_hw_frozen,
+	sdma_event_e82_hw_unfreeze,
+	sdma_event_e85_link_down,
+	sdma_event_e90_sw_halted,
+};
+
+struct sdma_set_state_action {
+	unsigned op_enable:1;
+	unsigned op_intenable:1;
+	unsigned op_halt:1;
+	unsigned op_cleanup:1;
+	unsigned go_s99_running_tofalse:1;
+	unsigned go_s99_running_totrue:1;
+};
+
+struct sdma_state {
+	struct kref          kref;
+	struct completion    comp;
+	enum sdma_states current_state;
+	unsigned             current_op;
+	unsigned             go_s99_running;
+	/* debugging/development */
+	enum sdma_states previous_state;
+	unsigned             previous_op;
+	enum sdma_events last_event;
+};
+
+/**
+ * DOC: sdma exported routines
+ *
+ * These sdma routines fit into three categories:
+ * - The SDMA API for building and submitting packets
+ *   to the ring
+ *
+ * - Initialization and tear down routines to buildup
+ *   and tear down SDMA
+ *
+ * - ISR entrances to handle interrupts, state changes
+ *   and errors
+ */
+
+/**
+ * DOC: sdma PSM/verbs API
+ *
+ * The sdma API is designed to be used by both PSM
+ * and verbs to supply packets to the SDMA ring.
+ *
+ * The usage of the API is as follows:
+ *
+ * Embed a struct iowait in the QP or
+ * PQ.  The iowait should be initialized with a
+ * call to iowait_init().
+ *
+ * The user of the API should create an allocation method
+ * for their version of the txreq. slabs, pre-allocated lists,
+ * and dma pools can be used.  Once the user's overload of
+ * the sdma_txreq has been allocated, the sdma_txreq member
+ * must be initialized with sdma_txinit() or sdma_txinit_ahg().
+ *
+ * The txreq must be declared with the sdma_txreq first.
+ *
+ * The tx request, once initialized,  is manipulated with calls to
+ * sdma_txadd_daddr(), sdma_txadd_page(), or sdma_txadd_kvaddr()
+ * for each disjoint memory location.  It is the user's responsibility
+ * to understand the packet boundaries and page boundaries to do the
+ * appropriate number of sdma_txadd_* calls..  The user
+ * must be prepared to deal with failures from these routines due to
+ * either memory allocation or dma_mapping failures.
+ *
+ * The mapping specifics for each memory location are recorded
+ * in the tx. Memory locations added with sdma_txadd_page()
+ * and sdma_txadd_kvaddr() are automatically mapped when added
+ * to the tx and nmapped as part of the progress processing in the
+ * SDMA interrupt handling.
+ *
+ * sdma_txadd_daddr() is used to add an dma_addr_t memory to the
+ * tx.   An example of a use case would be a pre-allocated
+ * set of headers allocated via dma_pool_alloc() or
+ * dma_alloc_coherent().  For these memory locations, it
+ * is the responsibility of the user to handle that unmapping.
+ * (This would usually be at an unload or job termination.)
+ *
+ * The routine sdma_send_txreq() is used to submit
+ * a tx to the ring after the appropriate number of
+ * sdma_txadd_* have been done.
+ *
+ * If it is desired to send a burst of sdma_txreqs, sdma_send_txlist()
+ * can be used to submit a list of packets.
+ *
+ * The user is free to use the link overhead in the struct sdma_txreq as
+ * long as the tx isn't in flight.
+ *
+ * The extreme degenerate case of the number of descriptors
+ * exceeding the ring size is automatically handled as
+ * memory locations are added.  An overflow of the descriptor
+ * array that is part of the sdma_txreq is also automatically
+ * handled.
+ *
+ */
+
+/**
+ * DOC: Infrastructure calls
+ *
+ * sdma_init() is used to initialize data structures and
+ * CSRs for the desired number of SDMA engines.
+ *
+ * sdma_start() is used to kick the SDMA engines initialized
+ * with sdma_init().   Interrupts must be enabled at this
+ * point since aspects of the state machine are interrupt
+ * driven.
+ *
+ * sdma_engine_error() and sdma_engine_interrupt() are
+ * entrances for interrupts.
+ *
+ * sdma_map_init() is for the management of the mapping
+ * table when the number of vls is changed.
+ *
+ */
+
+/*
+ * struct hw_sdma_desc - raw 128 bit SDMA descriptor
+ *
+ * This is the raw descriptor in the SDMA ring
+ */
+struct hw_sdma_desc {
+	/* private:  don't use directly */
+	__le64 qw[2];
+};
+
+/**
+ * struct sdma_engine - Data pertaining to each SDMA engine.
+ * @dd: a back-pointer to the device data
+ * @ppd: per port back-pointer
+ * @imask: mask for irq manipulation
+ * @idle_mask: mask for determining if an interrupt is due to sdma_idle
+ *
+ * This structure has the state for each sdma_engine.
+ *
+ * Accessing to non public fields are not supported
+ * since the private members are subject to change.
+ */
+struct sdma_engine {
+	/* read mostly */
+	struct hfi1_devdata *dd;
+	struct hfi1_pportdata *ppd;
+	/* private: */
+	void __iomem *tail_csr;
+	u64 imask;			/* clear interrupt mask */
+	u64 idle_mask;
+	u64 progress_mask;
+	u64 int_mask;
+	/* private: */
+	volatile __le64      *head_dma; /* DMA'ed by chip */
+	/* private: */
+	dma_addr_t            head_phys;
+	/* private: */
+	struct hw_sdma_desc *descq;
+	/* private: */
+	unsigned descq_full_count;
+	struct sdma_txreq **tx_ring;
+	/* private: */
+	dma_addr_t            descq_phys;
+	/* private */
+	u32 sdma_mask;
+	/* private */
+	struct sdma_state state;
+	/* private */
+	int cpu;
+	/* private: */
+	u8 sdma_shift;
+	/* private: */
+	u8 this_idx; /* zero relative engine */
+	/* protect changes to senddmactrl shadow */
+	spinlock_t senddmactrl_lock;
+	/* private: */
+	u64 p_senddmactrl;		/* shadow per-engine SendDmaCtrl */
+
+	/* read/write using tail_lock */
+	spinlock_t            tail_lock ____cacheline_aligned_in_smp;
+#ifdef CONFIG_HFI1_DEBUG_SDMA_ORDER
+	/* private: */
+	u64                   tail_sn;
+#endif
+	/* private: */
+	u32                   descq_tail;
+	/* private: */
+	unsigned long         ahg_bits;
+	/* private: */
+	u16                   desc_avail;
+	/* private: */
+	u16                   tx_tail;
+	/* private: */
+	u16 descq_cnt;
+
+	/* read/write using head_lock */
+	/* private: */
+	seqlock_t            head_lock ____cacheline_aligned_in_smp;
+#ifdef CONFIG_HFI1_DEBUG_SDMA_ORDER
+	/* private: */
+	u64                   head_sn;
+#endif
+	/* private: */
+	u32                   descq_head;
+	/* private: */
+	u16                   tx_head;
+	/* private: */
+	u64                   last_status;
+	/* private */
+	u64                     err_cnt;
+	/* private */
+	u64                     sdma_int_cnt;
+	u64                     idle_int_cnt;
+	u64                     progress_int_cnt;
+
+	/* private: */
+	struct list_head      dmawait;
+
+	/* CONFIG SDMA for now, just blindly duplicate */
+	/* private: */
+	struct tasklet_struct sdma_hw_clean_up_task
+		____cacheline_aligned_in_smp;
+
+	/* private: */
+	struct tasklet_struct sdma_sw_clean_up_task
+		____cacheline_aligned_in_smp;
+	/* private: */
+	struct work_struct err_halt_worker;
+	/* private */
+	struct timer_list     err_progress_check_timer;
+	u32                   progress_check_head;
+	/* private: */
+	struct work_struct flush_worker;
+	/* protect flush list */
+	spinlock_t flushlist_lock;
+	/* private: */
+	struct list_head flushlist;
+};
+
+int sdma_init(struct hfi1_devdata *dd, u8 port);
+void sdma_start(struct hfi1_devdata *dd);
+void sdma_exit(struct hfi1_devdata *dd);
+void sdma_all_running(struct hfi1_devdata *dd);
+void sdma_all_idle(struct hfi1_devdata *dd);
+void sdma_freeze_notify(struct hfi1_devdata *dd, int go_idle);
+void sdma_freeze(struct hfi1_devdata *dd);
+void sdma_unfreeze(struct hfi1_devdata *dd);
+void sdma_wait(struct hfi1_devdata *dd);
+
+/**
+ * sdma_empty() - idle engine test
+ * @engine: sdma engine
+ *
+ * Currently used by verbs as a latency optimization.
+ *
+ * Return:
+ * 1 - empty, 0 - non-empty
+ */
+static inline int sdma_empty(struct sdma_engine *sde)
+{
+	return sde->descq_tail == sde->descq_head;
+}
+
+static inline u16 sdma_descq_freecnt(struct sdma_engine *sde)
+{
+	return sde->descq_cnt -
+		(sde->descq_tail -
+		 ACCESS_ONCE(sde->descq_head)) - 1;
+}
+
+static inline u16 sdma_descq_inprocess(struct sdma_engine *sde)
+{
+	return sde->descq_cnt - sdma_descq_freecnt(sde);
+}
+
+/*
+ * Either head_lock or tail lock required to see
+ * a steady state.
+ */
+static inline int __sdma_running(struct sdma_engine *engine)
+{
+	return engine->state.current_state == sdma_state_s99_running;
+}
+
+/**
+ * sdma_running() - state suitability test
+ * @engine: sdma engine
+ *
+ * sdma_running probes the internal state to determine if it is suitable
+ * for submitting packets.
+ *
+ * Return:
+ * 1 - ok to submit, 0 - not ok to submit
+ *
+ */
+static inline int sdma_running(struct sdma_engine *engine)
+{
+	unsigned long flags;
+	int ret;
+
+	spin_lock_irqsave(&engine->tail_lock, flags);
+	ret = __sdma_running(engine);
+	spin_unlock_irqrestore(&engine->tail_lock, flags);
+	return ret;
+}
+
+void _sdma_txreq_ahgadd(
+	struct sdma_txreq *tx,
+	u8 num_ahg,
+	u8 ahg_entry,
+	u32 *ahg,
+	u8 ahg_hlen);
+
+/**
+ * sdma_txinit_ahg() - initialize an sdma_txreq struct with AHG
+ * @tx: tx request to initialize
+ * @flags: flags to key last descriptor additions
+ * @tlen: total packet length (pbc + headers + data)
+ * @ahg_entry: ahg entry to use  (0 - 31)
+ * @num_ahg: ahg descriptor for first descriptor (0 - 9)
+ * @ahg: array of AHG descriptors (up to 9 entries)
+ * @ahg_hlen: number of bytes from ASIC entry to use
+ * @cb: callback
+ *
+ * The allocation of the sdma_txreq and it enclosing structure is user
+ * dependent.  This routine must be called to initialize the user independent
+ * fields.
+ *
+ * The currently supported flags are SDMA_TXREQ_F_URGENT,
+ * SDMA_TXREQ_F_AHG_COPY, and SDMA_TXREQ_F_USE_AHG.
+ *
+ * SDMA_TXREQ_F_URGENT is used for latency sensitive situations where the
+ * completion is desired as soon as possible.
+ *
+ * SDMA_TXREQ_F_AHG_COPY causes the header in the first descriptor to be
+ * copied to chip entry. SDMA_TXREQ_F_USE_AHG causes the code to add in
+ * the AHG descriptors into the first 1 to 3 descriptors.
+ *
+ * Completions of submitted requests can be gotten on selected
+ * txreqs by giving a completion routine callback to sdma_txinit() or
+ * sdma_txinit_ahg().  The environment in which the callback runs
+ * can be from an ISR, a tasklet, or a thread, so no sleeping
+ * kernel routines can be used.   Aspects of the sdma ring may
+ * be locked so care should be taken with locking.
+ *
+ * The callback pointer can be NULL to avoid any callback for the packet
+ * being submitted. The callback will be provided this tx, a status, and a flag.
+ *
+ * The status will be one of SDMA_TXREQ_S_OK, SDMA_TXREQ_S_SENDERROR,
+ * SDMA_TXREQ_S_ABORTED, or SDMA_TXREQ_S_SHUTDOWN.
+ *
+ * The flag, if the is the iowait had been used, indicates the iowait
+ * sdma_busy count has reached zero.
+ *
+ * user data portion of tlen should be precise.   The sdma_txadd_* entrances
+ * will pad with a descriptor references 1 - 3 bytes when the number of bytes
+ * specified in tlen have been supplied to the sdma_txreq.
+ *
+ * ahg_hlen is used to determine the number of on-chip entry bytes to
+ * use as the header.   This is for cases where the stored header is
+ * larger than the header to be used in a packet.  This is typical
+ * for verbs where an RDMA_WRITE_FIRST is larger than the packet in
+ * and RDMA_WRITE_MIDDLE.
+ *
+ */
+static inline int sdma_txinit_ahg(
+	struct sdma_txreq *tx,
+	u16 flags,
+	u16 tlen,
+	u8 ahg_entry,
+	u8 num_ahg,
+	u32 *ahg,
+	u8 ahg_hlen,
+	void (*cb)(struct sdma_txreq *, int))
+{
+	if (tlen == 0)
+		return -ENODATA;
+	if (tlen > MAX_SDMA_PKT_SIZE)
+		return -EMSGSIZE;
+	tx->desc_limit = ARRAY_SIZE(tx->descs);
+	tx->descp = &tx->descs[0];
+	INIT_LIST_HEAD(&tx->list);
+	tx->num_desc = 0;
+	tx->flags = flags;
+	tx->complete = cb;
+	tx->coalesce_buf = NULL;
+	tx->wait = NULL;
+	tx->packet_len = tlen;
+	tx->tlen = tx->packet_len;
+	tx->descs[0].qw[0] = SDMA_DESC0_FIRST_DESC_FLAG;
+	tx->descs[0].qw[1] = 0;
+	if (flags & SDMA_TXREQ_F_AHG_COPY)
+		tx->descs[0].qw[1] |=
+			(((u64)ahg_entry & SDMA_DESC1_HEADER_INDEX_MASK)
+				<< SDMA_DESC1_HEADER_INDEX_SHIFT) |
+			(((u64)SDMA_AHG_COPY & SDMA_DESC1_HEADER_MODE_MASK)
+				<< SDMA_DESC1_HEADER_MODE_SHIFT);
+	else if (flags & SDMA_TXREQ_F_USE_AHG && num_ahg)
+		_sdma_txreq_ahgadd(tx, num_ahg, ahg_entry, ahg, ahg_hlen);
+	return 0;
+}
+
+/**
+ * sdma_txinit() - initialize an sdma_txreq struct (no AHG)
+ * @tx: tx request to initialize
+ * @flags: flags to key last descriptor additions
+ * @tlen: total packet length (pbc + headers + data)
+ * @cb: callback pointer
+ *
+ * The allocation of the sdma_txreq and it enclosing structure is user
+ * dependent.  This routine must be called to initialize the user
+ * independent fields.
+ *
+ * The currently supported flags is SDMA_TXREQ_F_URGENT.
+ *
+ * SDMA_TXREQ_F_URGENT is used for latency sensitive situations where the
+ * completion is desired as soon as possible.
+ *
+ * Completions of submitted requests can be gotten on selected
+ * txreqs by giving a completion routine callback to sdma_txinit() or
+ * sdma_txinit_ahg().  The environment in which the callback runs
+ * can be from an ISR, a tasklet, or a thread, so no sleeping
+ * kernel routines can be used.   The head size of the sdma ring may
+ * be locked so care should be taken with locking.
+ *
+ * The callback pointer can be NULL to avoid any callback for the packet
+ * being submitted.
+ *
+ * The callback, if non-NULL,  will be provided this tx and a status.  The
+ * status will be one of SDMA_TXREQ_S_OK, SDMA_TXREQ_S_SENDERROR,
+ * SDMA_TXREQ_S_ABORTED, or SDMA_TXREQ_S_SHUTDOWN.
+ *
+ */
+static inline int sdma_txinit(
+	struct sdma_txreq *tx,
+	u16 flags,
+	u16 tlen,
+	void (*cb)(struct sdma_txreq *, int))
+{
+	return sdma_txinit_ahg(tx, flags, tlen, 0, 0, NULL, 0, cb);
+}
+
+/* helpers - don't use */
+static inline int sdma_mapping_type(struct sdma_desc *d)
+{
+	return (d->qw[1] & SDMA_DESC1_GENERATION_SMASK)
+		>> SDMA_DESC1_GENERATION_SHIFT;
+}
+
+static inline size_t sdma_mapping_len(struct sdma_desc *d)
+{
+	return (d->qw[0] & SDMA_DESC0_BYTE_COUNT_SMASK)
+		>> SDMA_DESC0_BYTE_COUNT_SHIFT;
+}
+
+static inline dma_addr_t sdma_mapping_addr(struct sdma_desc *d)
+{
+	return (d->qw[0] & SDMA_DESC0_PHY_ADDR_SMASK)
+		>> SDMA_DESC0_PHY_ADDR_SHIFT;
+}
+
+static inline void make_tx_sdma_desc(
+	struct sdma_txreq *tx,
+	int type,
+	dma_addr_t addr,
+	size_t len)
+{
+	struct sdma_desc *desc = &tx->descp[tx->num_desc];
+
+	if (!tx->num_desc) {
+		/* qw[0] zero; qw[1] first, ahg mode already in from init */
+		desc->qw[1] |= ((u64)type & SDMA_DESC1_GENERATION_MASK)
+				<< SDMA_DESC1_GENERATION_SHIFT;
+	} else {
+		desc->qw[0] = 0;
+		desc->qw[1] = ((u64)type & SDMA_DESC1_GENERATION_MASK)
+				<< SDMA_DESC1_GENERATION_SHIFT;
+	}
+	desc->qw[0] |= (((u64)addr & SDMA_DESC0_PHY_ADDR_MASK)
+				<< SDMA_DESC0_PHY_ADDR_SHIFT) |
+			(((u64)len & SDMA_DESC0_BYTE_COUNT_MASK)
+				<< SDMA_DESC0_BYTE_COUNT_SHIFT);
+}
+
+/* helper to extend txreq */
+int ext_coal_sdma_tx_descs(struct hfi1_devdata *dd, struct sdma_txreq *tx,
+			   int type, void *kvaddr, struct page *page,
+			   unsigned long offset, u16 len);
+int _pad_sdma_tx_descs(struct hfi1_devdata *, struct sdma_txreq *);
+void sdma_txclean(struct hfi1_devdata *, struct sdma_txreq *);
+
+/* helpers used by public routines */
+static inline void _sdma_close_tx(struct hfi1_devdata *dd,
+				  struct sdma_txreq *tx)
+{
+	tx->descp[tx->num_desc].qw[0] |=
+		SDMA_DESC0_LAST_DESC_FLAG;
+	tx->descp[tx->num_desc].qw[1] |=
+		dd->default_desc1;
+	if (tx->flags & SDMA_TXREQ_F_URGENT)
+		tx->descp[tx->num_desc].qw[1] |=
+			(SDMA_DESC1_HEAD_TO_HOST_FLAG |
+			 SDMA_DESC1_INT_REQ_FLAG);
+}
+
+static inline int _sdma_txadd_daddr(
+	struct hfi1_devdata *dd,
+	int type,
+	struct sdma_txreq *tx,
+	dma_addr_t addr,
+	u16 len)
+{
+	int rval = 0;
+
+	make_tx_sdma_desc(
+		tx,
+		type,
+		addr, len);
+	WARN_ON(len > tx->tlen);
+	tx->tlen -= len;
+	/* special cases for last */
+	if (!tx->tlen) {
+		if (tx->packet_len & (sizeof(u32) - 1)) {
+			rval = _pad_sdma_tx_descs(dd, tx);
+			if (rval)
+				return rval;
+		} else {
+			_sdma_close_tx(dd, tx);
+		}
+	}
+	tx->num_desc++;
+	return rval;
+}
+
+/**
+ * sdma_txadd_page() - add a page to the sdma_txreq
+ * @dd: the device to use for mapping
+ * @tx: tx request to which the page is added
+ * @page: page to map
+ * @offset: offset within the page
+ * @len: length in bytes
+ *
+ * This is used to add a page/offset/length descriptor.
+ *
+ * The mapping/unmapping of the page/offset/len is automatically handled.
+ *
+ * Return:
+ * 0 - success, -ENOSPC - mapping fail, -ENOMEM - couldn't
+ * extend/coalesce descriptor array
+ */
+static inline int sdma_txadd_page(
+	struct hfi1_devdata *dd,
+	struct sdma_txreq *tx,
+	struct page *page,
+	unsigned long offset,
+	u16 len)
+{
+	dma_addr_t addr;
+	int rval;
+
+	if ((unlikely(tx->num_desc == tx->desc_limit))) {
+		rval = ext_coal_sdma_tx_descs(dd, tx, SDMA_MAP_PAGE,
+					      NULL, page, offset, len);
+		if (rval <= 0)
+			return rval;
+	}
+
+	addr = dma_map_page(
+		       &dd->pcidev->dev,
+		       page,
+		       offset,
+		       len,
+		       DMA_TO_DEVICE);
+
+	if (unlikely(dma_mapping_error(&dd->pcidev->dev, addr))) {
+		sdma_txclean(dd, tx);
+		return -ENOSPC;
+	}
+
+	return _sdma_txadd_daddr(
+			dd, SDMA_MAP_PAGE, tx, addr, len);
+}
+
+/**
+ * sdma_txadd_daddr() - add a dma address to the sdma_txreq
+ * @dd: the device to use for mapping
+ * @tx: sdma_txreq to which the page is added
+ * @addr: dma address mapped by caller
+ * @len: length in bytes
+ *
+ * This is used to add a descriptor for memory that is already dma mapped.
+ *
+ * In this case, there is no unmapping as part of the progress processing for
+ * this memory location.
+ *
+ * Return:
+ * 0 - success, -ENOMEM - couldn't extend descriptor array
+ */
+
+static inline int sdma_txadd_daddr(
+	struct hfi1_devdata *dd,
+	struct sdma_txreq *tx,
+	dma_addr_t addr,
+	u16 len)
+{
+	int rval;
+
+	if ((unlikely(tx->num_desc == tx->desc_limit))) {
+		rval = ext_coal_sdma_tx_descs(dd, tx, SDMA_MAP_NONE,
+					      NULL, NULL, 0, 0);
+		if (rval <= 0)
+			return rval;
+	}
+
+	return _sdma_txadd_daddr(dd, SDMA_MAP_NONE, tx, addr, len);
+}
+
+/**
+ * sdma_txadd_kvaddr() - add a kernel virtual address to sdma_txreq
+ * @dd: the device to use for mapping
+ * @tx: sdma_txreq to which the page is added
+ * @kvaddr: the kernel virtual address
+ * @len: length in bytes
+ *
+ * This is used to add a descriptor referenced by the indicated kvaddr and
+ * len.
+ *
+ * The mapping/unmapping of the kvaddr and len is automatically handled.
+ *
+ * Return:
+ * 0 - success, -ENOSPC - mapping fail, -ENOMEM - couldn't extend/coalesce
+ * descriptor array
+ */
+static inline int sdma_txadd_kvaddr(
+	struct hfi1_devdata *dd,
+	struct sdma_txreq *tx,
+	void *kvaddr,
+	u16 len)
+{
+	dma_addr_t addr;
+	int rval;
+
+	if ((unlikely(tx->num_desc == tx->desc_limit))) {
+		rval = ext_coal_sdma_tx_descs(dd, tx, SDMA_MAP_SINGLE,
+					      kvaddr, NULL, 0, len);
+		if (rval <= 0)
+			return rval;
+	}
+
+	addr = dma_map_single(
+		       &dd->pcidev->dev,
+		       kvaddr,
+		       len,
+		       DMA_TO_DEVICE);
+
+	if (unlikely(dma_mapping_error(&dd->pcidev->dev, addr))) {
+		sdma_txclean(dd, tx);
+		return -ENOSPC;
+	}
+
+	return _sdma_txadd_daddr(
+			dd, SDMA_MAP_SINGLE, tx, addr, len);
+}
+
+struct iowait;
+
+int sdma_send_txreq(struct sdma_engine *sde,
+		    struct iowait *wait,
+		    struct sdma_txreq *tx);
+int sdma_send_txlist(struct sdma_engine *sde,
+		     struct iowait *wait,
+		     struct list_head *tx_list);
+
+int sdma_ahg_alloc(struct sdma_engine *sde);
+void sdma_ahg_free(struct sdma_engine *sde, int ahg_index);
+
+/**
+ * sdma_build_ahg - build ahg descriptor
+ * @data
+ * @dwindex
+ * @startbit
+ * @bits
+ *
+ * Build and return a 32 bit descriptor.
+ */
+static inline u32 sdma_build_ahg_descriptor(
+	u16 data,
+	u8 dwindex,
+	u8 startbit,
+	u8 bits)
+{
+	return (u32)(1UL << SDMA_AHG_UPDATE_ENABLE_SHIFT |
+		((startbit & SDMA_AHG_FIELD_START_MASK) <<
+		SDMA_AHG_FIELD_START_SHIFT) |
+		((bits & SDMA_AHG_FIELD_LEN_MASK) <<
+		SDMA_AHG_FIELD_LEN_SHIFT) |
+		((dwindex & SDMA_AHG_INDEX_MASK) <<
+		SDMA_AHG_INDEX_SHIFT) |
+		((data & SDMA_AHG_VALUE_MASK) <<
+		SDMA_AHG_VALUE_SHIFT));
+}
+
+/**
+ * sdma_progress - use seq number of detect head progress
+ * @sde: sdma_engine to check
+ * @seq: base seq count
+ * @tx: txreq for which we need to check descriptor availability
+ *
+ * This is used in the appropriate spot in the sleep routine
+ * to check for potential ring progress.  This routine gets the
+ * seqcount before queuing the iowait structure for progress.
+ *
+ * If the seqcount indicates that progress needs to be checked,
+ * re-submission is detected by checking whether the descriptor
+ * queue has enough descriptor for the txreq.
+ */
+static inline unsigned sdma_progress(struct sdma_engine *sde, unsigned seq,
+				     struct sdma_txreq *tx)
+{
+	if (read_seqretry(&sde->head_lock, seq)) {
+		sde->desc_avail = sdma_descq_freecnt(sde);
+		if (tx->num_desc > sde->desc_avail)
+			return 0;
+		return 1;
+	}
+	return 0;
+}
+
+/**
+ * sdma_iowait_schedule() - initialize wait structure
+ * @sde: sdma_engine to schedule
+ * @wait: wait struct to schedule
+ *
+ * This function initializes the iowait
+ * structure embedded in the QP or PQ.
+ *
+ */
+static inline void sdma_iowait_schedule(
+	struct sdma_engine *sde,
+	struct iowait *wait)
+{
+	struct hfi1_pportdata *ppd = sde->dd->pport;
+
+	iowait_schedule(wait, ppd->hfi1_wq, sde->cpu);
+}
+
+/* for use by interrupt handling */
+void sdma_engine_error(struct sdma_engine *sde, u64 status);
+void sdma_engine_interrupt(struct sdma_engine *sde, u64 status);
+
+/*
+ *
+ * The diagram below details the relationship of the mapping structures
+ *
+ * Since the mapping now allows for non-uniform engines per vl, the
+ * number of engines for a vl is either the vl_engines[vl] or
+ * a computation based on num_sdma/num_vls:
+ *
+ * For example:
+ * nactual = vl_engines ? vl_engines[vl] : num_sdma/num_vls
+ *
+ * n = roundup to next highest power of 2 using nactual
+ *
+ * In the case where there are num_sdma/num_vls doesn't divide
+ * evenly, the extras are added from the last vl downward.
+ *
+ * For the case where n > nactual, the engines are assigned
+ * in a round robin fashion wrapping back to the first engine
+ * for a particular vl.
+ *
+ *               dd->sdma_map
+ *                    |                                   sdma_map_elem[0]
+ *                    |                                +--------------------+
+ *                    v                                |       mask         |
+ *               sdma_vl_map                           |--------------------|
+ *      +--------------------------+                   | sde[0] -> eng 1    |
+ *      |    list (RCU)            |                   |--------------------|
+ *      |--------------------------|                 ->| sde[1] -> eng 2    |
+ *      |    mask                  |              --/  |--------------------|
+ *      |--------------------------|            -/     |        *           |
+ *      |    actual_vls (max 8)    |          -/       |--------------------|
+ *      |--------------------------|       --/         | sde[n] -> eng n    |
+ *      |    vls (max 8)           |     -/            +--------------------+
+ *      |--------------------------|  --/
+ *      |    map[0]                |-/
+ *      |--------------------------|                   +--------------------+
+ *      |    map[1]                |---                |       mask         |
+ *      |--------------------------|   \----           |--------------------|
+ *      |           *              |        \--        | sde[0] -> eng 1+n  |
+ *      |           *              |           \----   |--------------------|
+ *      |           *              |                \->| sde[1] -> eng 2+n  |
+ *      |--------------------------|                   |--------------------|
+ *      |   map[vls - 1]           |-                  |         *          |
+ *      +--------------------------+ \-                |--------------------|
+ *                                     \-              | sde[m] -> eng m+n  |
+ *                                       \             +--------------------+
+ *                                        \-
+ *                                          \
+ *                                           \-        +--------------------+
+ *                                             \-      |       mask         |
+ *                                               \     |--------------------|
+ *                                                \-   | sde[0] -> eng 1+m+n|
+ *                                                  \- |--------------------|
+ *                                                    >| sde[1] -> eng 2+m+n|
+ *                                                     |--------------------|
+ *                                                     |         *          |
+ *                                                     |--------------------|
+ *                                                     | sde[o] -> eng o+m+n|
+ *                                                     +--------------------+
+ *
+ */
+
+/**
+ * struct sdma_map_elem - mapping for a vl
+ * @mask - selector mask
+ * @sde - array of engines for this vl
+ *
+ * The mask is used to "mod" the selector
+ * to produce index into the trailing
+ * array of sdes.
+ */
+struct sdma_map_elem {
+	u32 mask;
+	struct sdma_engine *sde[0];
+};
+
+/**
+ * struct sdma_map_el - mapping for a vl
+ * @engine_to_vl - map of an engine to a vl
+ * @list - rcu head for free callback
+ * @mask - vl mask to "mod" the vl to produce an index to map array
+ * @actual_vls - number of vls
+ * @vls - number of vls rounded to next power of 2
+ * @map - array of sdma_map_elem entries
+ *
+ * This is the parent mapping structure.  The trailing
+ * members of the struct point to sdma_map_elem entries, which
+ * in turn point to an array of sde's for that vl.
+ */
+struct sdma_vl_map {
+	s8 engine_to_vl[TXE_NUM_SDMA_ENGINES];
+	struct rcu_head list;
+	u32 mask;
+	u8 actual_vls;
+	u8 vls;
+	struct sdma_map_elem *map[0];
+};
+
+int sdma_map_init(
+	struct hfi1_devdata *dd,
+	u8 port,
+	u8 num_vls,
+	u8 *vl_engines);
+
+/* slow path */
+void _sdma_engine_progress_schedule(struct sdma_engine *sde);
+
+/**
+ * sdma_engine_progress_schedule() - schedule progress on engine
+ * @sde: sdma_engine to schedule progress
+ *
+ * This is the fast path.
+ *
+ */
+static inline void sdma_engine_progress_schedule(
+	struct sdma_engine *sde)
+{
+	if (!sde || sdma_descq_inprocess(sde) < (sde->descq_cnt / 8))
+		return;
+	_sdma_engine_progress_schedule(sde);
+}
+
+struct sdma_engine *sdma_select_engine_sc(
+	struct hfi1_devdata *dd,
+	u32 selector,
+	u8 sc5);
+
+struct sdma_engine *sdma_select_engine_vl(
+	struct hfi1_devdata *dd,
+	u32 selector,
+	u8 vl);
+
+void sdma_seqfile_dump_sde(struct seq_file *s, struct sdma_engine *);
+
+#ifdef CONFIG_SDMA_VERBOSITY
+void sdma_dumpstate(struct sdma_engine *);
+#endif
+static inline char *slashstrip(char *s)
+{
+	char *r = s;
+
+	while (*s)
+		if (*s++ == '/')
+			r = s;
+	return r;
+}
+
+u16 sdma_get_descq_cnt(void);
+
+extern uint mod_num_sdma;
+
+void sdma_update_lmc(struct hfi1_devdata *dd, u64 mask, u32 lid);
+
+#endif