diff mbox

[v2,37/49] IB/hfi1: add sdma header file

Message ID 20150615132918.29741.4055.stgit@phlsvslse11.ph.intel.com (mailing list archive)
State Superseded
Headers show

Commit Message

Marciniszyn, Mike June 15, 2015, 1:29 p.m. UTC
Signed-off-by: Andrew Friedley <andrew.friedley@intel.com>
Signed-off-by: Arthur Kepner <arthur.kepner@intel.com>
Signed-off-by: Brendan Cunningham <brendan.cunningham@intel.com>
Signed-off-by: Brian Welty <brian.welty@intel.com>
Signed-off-by: Caz Yokoyama <caz.yokoyama@intel.com>
Signed-off-by: Dean Luick <dean.luick@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Easwar Hariharan <easwar.hariharan@intel.com>
Signed-off-by: Harish Chegondi <harish.chegondi@intel.com>
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Jim Snow <jim.m.snow@intel.com>
Signed-off-by: John Gregor <john.a.gregor@intel.com>
Signed-off-by: Jubin John <jubin.john@intel.com>
Signed-off-by: Kaike Wan <kaike.wan@intel.com>
Signed-off-by: Kevin Pine <kevin.pine@intel.com>
Signed-off-by: Kyle Liddell <kyle.liddell@intel.com>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Mitko Haralanov <mitko.haralanov@intel.com>
Signed-off-by: Ravi Krishnaswamy <ravi.krishnaswamy@intel.com>
Signed-off-by: Sadanand Warrier <sadanand.warrier@intel.com>
Signed-off-by: Sanath Kumar <sanath.s.kumar@intel.com>
Signed-off-by: Sudeep Dutt <sudeep.dutt@intel.com>
Signed-off-by: Vlad Danushevsky <vladimir.danusevsky@intel.com>
---
 drivers/infiniband/hw/hfi1/sdma.h | 1122 +++++++++++++++++++++++++++++++++++++
 1 file changed, 1122 insertions(+)
 create mode 100644 drivers/infiniband/hw/hfi1/sdma.h


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diff mbox

Patch

diff --git a/drivers/infiniband/hw/hfi1/sdma.h b/drivers/infiniband/hw/hfi1/sdma.h
new file mode 100644
index 0000000..2d2ff07
--- /dev/null
+++ b/drivers/infiniband/hw/hfi1/sdma.h
@@ -0,0 +1,1122 @@ 
+#ifndef _HFI1_SDMA_H
+#define _HFI1_SDMA_H
+/*
+ *
+ * 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
+ *
+ * Copyright(c) 2015 Intel Corporation.
+ *
+ * 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
+ *
+ * Copyright(c) 2015 Intel Corporation.
+ *
+ * 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"
+
+/* increased for AHG */
+#define NUM_DESC 6
+/* 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      (1ULL<<63)
+#define SDMA_DESC0_LAST_DESC_FLAG       (1ULL<<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)-1ULL)
+#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)-1ULL)
+#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)-1ULL)
+#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)-1ULL)
+#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)-1ULL)
+#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)-1ULL)
+#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)-1ULL)
+#define SDMA_DESC1_GENERATION_SMASK \
+	(SDMA_DESC1_GENERATION_MASK<<SDMA_DESC1_GENERATION_SHIFT)
+#define SDMA_DESC1_INT_REQ_FLAG         (1ULL<<1)
+#define SDMA_DESC1_HEAD_TO_HOST_FLAG    (1ULL<<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_desc - canonical fragment descriptor
+ *
+ * This is the descriptor carried in the tx request
+ * corresponding to each fragment.
+ *
+ */
+struct sdma_desc {
+	/* private:  don't use directly */
+	u64 qw[2];
+};
+
+struct sdma_txreq;
+typedef void (*callback_t)(struct sdma_txreq *, int, int);
+
+/**
+ * struct sdma_txreq - the sdma_txreq structure (one per packet)
+ * @list: for use by user and by queuing for wait
+ *
+ * This is the representation of a packet which consists of some
+ * number of fragments.   Storage is provided to within the structure.
+ * for all fragments.
+ *
+ * The storage for the descriptors are automatically extended as needed
+ * when the currently allocation is exceeded.
+ *
+ * The user (Verbs or PSM) may overload this structure with fields
+ * specific to their use by putting this struct first in their struct.
+ * The method of allocation of the overloaded structure is user dependent
+ *
+ * The list is the only public field in the structure.
+ *
+ */
+
+struct sdma_txreq {
+	struct list_head list;
+	/* private: */
+	struct sdma_desc *descp;
+	/* private: */
+	void *coalesce_buf;
+	/* private: */
+	struct iowait *wait;
+	/* private: */
+	callback_t                  complete;
+#ifdef CONFIG_HFI1_DEBUG_SDMA_ORDER
+	u64 sn;
+#endif
+	/* private: - used in coalesce/pad processing */
+	u16                         packet_len;
+	/* private: - down-counted to trigger last */
+	u16                         tlen;
+	/* private: flags */
+	u16                         flags;
+	/* private: */
+	u16                         num_desc;
+	/* private: */
+	u16                         desc_limit;
+	/* private: */
+	u16                         next_descq_idx;
+	/* private: */
+	struct sdma_desc descs[NUM_DESC];
+};
+
+struct verbs_txreq {
+	struct sdma_txreq       txreq;
+	struct hfi1_qp           *qp;
+	struct hfi1_swqe         *wqe;
+	struct hfi1_mregion	*mr;
+	struct hfi1_sge_state    *ss;
+	struct sdma_engine     *sde;
+	u16                     hdr_dwords;
+	u16                     hdr_inx;
+};
+
+/**
+ * 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;
+	/* private: */
+	struct workqueue_struct *wq;
+	/* 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: */
+	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: */
+	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;
+	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, 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->tlen = tx->packet_len = tlen;
+	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, 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 _extend_sdma_tx_descs(struct hfi1_devdata *, struct sdma_txreq *);
+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;
+
+	if ((unlikely(tx->num_desc == tx->desc_limit))) {
+		rval = _extend_sdma_tx_descs(dd, tx);
+		if (rval)
+			return rval;
+	}
+	make_tx_sdma_desc(
+		tx,
+		type,
+		addr, len);
+	BUG_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);
+		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 descriptor array or couldn't allocate coalesce
+ * buffer.
+ *
+ */
+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 =
+		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)
+{
+	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
+ * descriptor array
+ */
+static inline int sdma_txadd_kvaddr(
+	struct hfi1_devdata *dd,
+	struct sdma_txreq *tx,
+	void *kvaddr,
+	u16 len)
+{
+	dma_addr_t 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)
+{
+	iowait_schedule(wait, sde->wq);
+}
+
+/* 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
+ * @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 {
+	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