1 files changed, 300 insertions, 0 deletions
diff --git a/drivers/infiniband/hw/hfi1/iowait.h b/drivers/infiniband/hw/hfi1/iowait.h
new file mode 100644
index 000000000..2ec6ef38d
--- /dev/null
+++ b/drivers/infiniband/hw/hfi1/iowait.h
@@ -0,0 +1,300 @@
+#ifndef _HFI1_IOWAIT_H
+#define _HFI1_IOWAIT_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/list.h>
+#include <linux/workqueue.h>
+#include <linux/sched.h>
+
+#include "sdma_txreq.h"
+
+/*
+ * typedef (*restart_t)() - restart callback
+ * @work: pointer to work structure
+ */
+typedef void (*restart_t)(struct work_struct *work);
+
+struct sdma_txreq;
+struct sdma_engine;
+/**
+ * struct iowait - linkage for delayed progress/waiting
+ * @list: used to add/insert into QP/PQ wait lists
+ * @tx_head: overflow list of sdma_txreq's
+ * @sleep: no space callback
+ * @wakeup: space callback wakeup
+ * @sdma_drained: sdma count drained
+ * @iowork: workqueue overhead
+ * @wait_dma: wait for sdma_busy == 0
+ * @wait_pio: wait for pio_busy == 0
+ * @sdma_busy: # of packets in flight
+ * @count: total number of descriptors in tx_head'ed list
+ * @tx_limit: limit for overflow queuing
+ * @tx_count: number of tx entry's in tx_head'ed list
+ *
+ * This is to be embedded in user's state structure
+ * (QP or PQ).
+ *
+ * The sleep and wakeup members are a
+ * bit misnamed.   They do not strictly
+ * speaking sleep or wake up, but they
+ * are callbacks for the ULP to implement
+ * what ever queuing/dequeuing of
+ * the embedded iowait and its containing struct
+ * when a resource shortage like SDMA ring space is seen.
+ *
+ * Both potentially have locks help
+ * so sleeping is not allowed.
+ *
+ * The wait_dma member along with the iow
+ */
+
+struct iowait {
+	struct list_head list;
+	struct list_head tx_head;
+	int (*sleep)(
+		struct sdma_engine *sde,
+		struct iowait *wait,
+		struct sdma_txreq *tx,
+		unsigned seq);
+	void (*wakeup)(struct iowait *wait, int reason);
+	void (*sdma_drained)(struct iowait *wait);
+	struct work_struct iowork;
+	wait_queue_head_t wait_dma;
+	wait_queue_head_t wait_pio;
+	atomic_t sdma_busy;
+	atomic_t pio_busy;
+	u32 count;
+	u32 tx_limit;
+	u32 tx_count;
+};
+
+#define SDMA_AVAIL_REASON 0
+
+/**
+ * iowait_init() - initialize wait structure
+ * @wait: wait struct to initialize
+ * @tx_limit: limit for overflow queuing
+ * @func: restart function for workqueue
+ * @sleep: sleep function for no space
+ * @resume: wakeup function for no space
+ *
+ * This function initializes the iowait
+ * structure embedded in the QP or PQ.
+ *
+ */
+
+static inline void iowait_init(
+	struct iowait *wait,
+	u32 tx_limit,
+	void (*func)(struct work_struct *work),
+	int (*sleep)(
+		struct sdma_engine *sde,
+		struct iowait *wait,
+		struct sdma_txreq *tx,
+		unsigned seq),
+	void (*wakeup)(struct iowait *wait, int reason),
+	void (*sdma_drained)(struct iowait *wait))
+{
+	wait->count = 0;
+	INIT_LIST_HEAD(&wait->list);
+	INIT_LIST_HEAD(&wait->tx_head);
+	INIT_WORK(&wait->iowork, func);
+	init_waitqueue_head(&wait->wait_dma);
+	init_waitqueue_head(&wait->wait_pio);
+	atomic_set(&wait->sdma_busy, 0);
+	atomic_set(&wait->pio_busy, 0);
+	wait->tx_limit = tx_limit;
+	wait->sleep = sleep;
+	wait->wakeup = wakeup;
+	wait->sdma_drained = sdma_drained;
+}
+
+/**
+ * iowait_schedule() - initialize wait structure
+ * @wait: wait struct to schedule
+ * @wq: workqueue for schedule
+ * @cpu: cpu
+ */
+static inline void iowait_schedule(
+	struct iowait *wait,
+	struct workqueue_struct *wq,
+	int cpu)
+{
+	queue_work_on(cpu, wq, &wait->iowork);
+}
+
+/**
+ * iowait_sdma_drain() - wait for DMAs to drain
+ *
+ * @wait: iowait structure
+ *
+ * This will delay until the iowait sdmas have
+ * completed.
+ */
+static inline void iowait_sdma_drain(struct iowait *wait)
+{
+	wait_event(wait->wait_dma, !atomic_read(&wait->sdma_busy));
+}
+
+/**
+ * iowait_sdma_pending() - return sdma pending count
+ *
+ * @wait: iowait structure
+ *
+ */
+static inline int iowait_sdma_pending(struct iowait *wait)
+{
+	return atomic_read(&wait->sdma_busy);
+}
+
+/**
+ * iowait_sdma_inc - note sdma io pending
+ * @wait: iowait structure
+ */
+static inline void iowait_sdma_inc(struct iowait *wait)
+{
+	atomic_inc(&wait->sdma_busy);
+}
+
+/**
+ * iowait_sdma_add - add count to pending
+ * @wait: iowait structure
+ */
+static inline void iowait_sdma_add(struct iowait *wait, int count)
+{
+	atomic_add(count, &wait->sdma_busy);
+}
+
+/**
+ * iowait_sdma_dec - note sdma complete
+ * @wait: iowait structure
+ */
+static inline int iowait_sdma_dec(struct iowait *wait)
+{
+	return atomic_dec_and_test(&wait->sdma_busy);
+}
+
+/**
+ * iowait_pio_drain() - wait for pios to drain
+ *
+ * @wait: iowait structure
+ *
+ * This will delay until the iowait pios have
+ * completed.
+ */
+static inline void iowait_pio_drain(struct iowait *wait)
+{
+	wait_event_timeout(wait->wait_pio,
+			   !atomic_read(&wait->pio_busy),
+			   HZ);
+}
+
+/**
+ * iowait_pio_pending() - return pio pending count
+ *
+ * @wait: iowait structure
+ *
+ */
+static inline int iowait_pio_pending(struct iowait *wait)
+{
+	return atomic_read(&wait->pio_busy);
+}
+
+/**
+ * iowait_pio_inc - note pio pending
+ * @wait: iowait structure
+ */
+static inline void iowait_pio_inc(struct iowait *wait)
+{
+	atomic_inc(&wait->pio_busy);
+}
+
+/**
+ * iowait_sdma_dec - note pio complete
+ * @wait: iowait structure
+ */
+static inline int iowait_pio_dec(struct iowait *wait)
+{
+	return atomic_dec_and_test(&wait->pio_busy);
+}
+
+/**
+ * iowait_drain_wakeup() - trigger iowait_drain() waiter
+ *
+ * @wait: iowait structure
+ *
+ * This will trigger any waiters.
+ */
+static inline void iowait_drain_wakeup(struct iowait *wait)
+{
+	wake_up(&wait->wait_dma);
+	wake_up(&wait->wait_pio);
+	if (wait->sdma_drained)
+		wait->sdma_drained(wait);
+}
+
+/**
+ * iowait_get_txhead() - get packet off of iowait list
+ *
+ * @wait wait struture
+ */
+static inline struct sdma_txreq *iowait_get_txhead(struct iowait *wait)
+{
+	struct sdma_txreq *tx = NULL;
+
+	if (!list_empty(&wait->tx_head)) {
+		tx = list_first_entry(
+			&wait->tx_head,
+			struct sdma_txreq,
+			list);
+		list_del_init(&tx->list);
+	}
+	return tx;
+}
+
+#endif