Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/async_tx

* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/async_tx:
  ioat: fix 'ack' handling, driver must ensure that 'ack' is zero
  dmaengine: fix sparse warning
  fsldma: do not cleanup descriptors in hardirq context
  dmaengine: add driver for Freescale MPC85xx DMA controller

MAINTAINERS

@@ -1589,6 +1589,13 @@ L:	linux-fbdev-devel@lists.sourceforge.net (moderated for non-subscribers)
 W:	http://linux-fbdev.sourceforge.net/
 S:	Maintained
 
+FREESCALE DMA DRIVER
+P;	Zhang Wei
+M:	wei.zhang@freescale.com
+L:	linuxppc-embedded@ozlabs.org
+L:	linux-kernel@vger.kernel.org
+S:	Maintained
+
 FREESCALE SOC FS_ENET DRIVER
 P:	Pantelis Antoniou
 M:	pantelis.antoniou@gmail.com

drivers/dma/Kconfig

@@ -4,7 +4,7 @@
 
 menuconfig DMADEVICES
 	bool "DMA Engine support"
-	depends on (PCI && X86) || ARCH_IOP32X || ARCH_IOP33X || ARCH_IOP13XX
+	depends on (PCI && X86) || ARCH_IOP32X || ARCH_IOP33X || ARCH_IOP13XX || PPC
 	depends on !HIGHMEM64G
 	help
 	  DMA engines can do asynchronous data transfers without
@@ -37,6 +37,23 @@ config INTEL_IOP_ADMA
 	help
 	  Enable support for the Intel(R) IOP Series RAID engines.
 
+config FSL_DMA
+	bool "Freescale MPC85xx/MPC83xx DMA support"
+	depends on PPC
+	select DMA_ENGINE
+	---help---
+	  Enable support for the Freescale DMA engine. Now, it support
+	  MPC8560/40, MPC8555, MPC8548 and MPC8641 processors.
+	  The MPC8349, MPC8360 is also supported.
+
+config FSL_DMA_SELFTEST
+	bool "Enable the self test for each DMA channel"
+	depends on FSL_DMA
+	default y
+	---help---
+	  Enable the self test for each DMA channel. A self test will be
+	  performed after the channel probed to ensure the DMA works well.
+
 config DMA_ENGINE
 	bool
 

drivers/dma/Makefile

@@ -3,3 +3,4 @@ obj-$(CONFIG_NET_DMA) += iovlock.o
 obj-$(CONFIG_INTEL_IOATDMA) += ioatdma.o
 ioatdma-objs := ioat.o ioat_dma.o ioat_dca.o
 obj-$(CONFIG_INTEL_IOP_ADMA) += iop-adma.o
+obj-$(CONFIG_FSL_DMA) += fsldma.o

drivers/dma/fsldma.c

+/*
+ * Freescale MPC85xx, MPC83xx DMA Engine support
+ *
+ * Copyright (C) 2007 Freescale Semiconductor, Inc. All rights reserved.
+ *
+ * Author:
+ *   Zhang Wei <wei.zhang@freescale.com>, Jul 2007
+ *   Ebony Zhu <ebony.zhu@freescale.com>, May 2007
+ *
+ * Description:
+ *   DMA engine driver for Freescale MPC8540 DMA controller, which is
+ *   also fit for MPC8560, MPC8555, MPC8548, MPC8641, and etc.
+ *   The support for MPC8349 DMA contorller is also added.
+ *
+ * This is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <linux/interrupt.h>
+#include <linux/dmaengine.h>
+#include <linux/delay.h>
+#include <linux/dma-mapping.h>
+#include <linux/dmapool.h>
+#include <linux/of_platform.h>
+
+#include "fsldma.h"
+
+static void dma_init(struct fsl_dma_chan *fsl_chan)
+{
+	/* Reset the channel */
+	DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr, 0, 32);
+
+	switch (fsl_chan->feature & FSL_DMA_IP_MASK) {
+	case FSL_DMA_IP_85XX:
+		/* Set the channel to below modes:
+		 * EIE - Error interrupt enable
+		 * EOSIE - End of segments interrupt enable (basic mode)
+		 * EOLNIE - End of links interrupt enable
+		 */
+		DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr, FSL_DMA_MR_EIE
+				| FSL_DMA_MR_EOLNIE | FSL_DMA_MR_EOSIE, 32);
+		break;
+	case FSL_DMA_IP_83XX:
+		/* Set the channel to below modes:
+		 * EOTIE - End-of-transfer interrupt enable
+		 */
+		DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr, FSL_DMA_MR_EOTIE,
+				32);
+		break;
+	}
+
+}
+
+static void set_sr(struct fsl_dma_chan *fsl_chan, dma_addr_t val)
+{
+	DMA_OUT(fsl_chan, &fsl_chan->reg_base->sr, val, 32);
+}
+
+static dma_addr_t get_sr(struct fsl_dma_chan *fsl_chan)
+{
+	return DMA_IN(fsl_chan, &fsl_chan->reg_base->sr, 32);
+}
+
+static void set_desc_cnt(struct fsl_dma_chan *fsl_chan,
+				struct fsl_dma_ld_hw *hw, u32 count)
+{
+	hw->count = CPU_TO_DMA(fsl_chan, count, 32);
+}
+
+static void set_desc_src(struct fsl_dma_chan *fsl_chan,
+				struct fsl_dma_ld_hw *hw, dma_addr_t src)
+{
+	u64 snoop_bits;
+
+	snoop_bits = ((fsl_chan->feature & FSL_DMA_IP_MASK) == FSL_DMA_IP_85XX)
+		? ((u64)FSL_DMA_SATR_SREADTYPE_SNOOP_READ << 32) : 0;
+	hw->src_addr = CPU_TO_DMA(fsl_chan, snoop_bits | src, 64);
+}
+
+static void set_desc_dest(struct fsl_dma_chan *fsl_chan,
+				struct fsl_dma_ld_hw *hw, dma_addr_t dest)
+{
+	u64 snoop_bits;
+
+	snoop_bits = ((fsl_chan->feature & FSL_DMA_IP_MASK) == FSL_DMA_IP_85XX)
+		? ((u64)FSL_DMA_DATR_DWRITETYPE_SNOOP_WRITE << 32) : 0;
+	hw->dst_addr = CPU_TO_DMA(fsl_chan, snoop_bits | dest, 64);
+}
+
+static void set_desc_next(struct fsl_dma_chan *fsl_chan,
+				struct fsl_dma_ld_hw *hw, dma_addr_t next)
+{
+	u64 snoop_bits;
+
+	snoop_bits = ((fsl_chan->feature & FSL_DMA_IP_MASK) == FSL_DMA_IP_83XX)
+		? FSL_DMA_SNEN : 0;
+	hw->next_ln_addr = CPU_TO_DMA(fsl_chan, snoop_bits | next, 64);
+}
+
+static void set_cdar(struct fsl_dma_chan *fsl_chan, dma_addr_t addr)
+{
+	DMA_OUT(fsl_chan, &fsl_chan->reg_base->cdar, addr | FSL_DMA_SNEN, 64);
+}
+
+static dma_addr_t get_cdar(struct fsl_dma_chan *fsl_chan)
+{
+	return DMA_IN(fsl_chan, &fsl_chan->reg_base->cdar, 64) & ~FSL_DMA_SNEN;
+}
+
+static void set_ndar(struct fsl_dma_chan *fsl_chan, dma_addr_t addr)
+{
+	DMA_OUT(fsl_chan, &fsl_chan->reg_base->ndar, addr, 64);
+}
+
+static dma_addr_t get_ndar(struct fsl_dma_chan *fsl_chan)
+{
+	return DMA_IN(fsl_chan, &fsl_chan->reg_base->ndar, 64);
+}
+
+static int dma_is_idle(struct fsl_dma_chan *fsl_chan)
+{
+	u32 sr = get_sr(fsl_chan);
+	return (!(sr & FSL_DMA_SR_CB)) || (sr & FSL_DMA_SR_CH);
+}
+
+static void dma_start(struct fsl_dma_chan *fsl_chan)
+{
+	u32 mr_set = 0;;
+
+	if (fsl_chan->feature & FSL_DMA_CHAN_PAUSE_EXT) {
+		DMA_OUT(fsl_chan, &fsl_chan->reg_base->bcr, 0, 32);
+		mr_set |= FSL_DMA_MR_EMP_EN;
+	} else
+		DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr,
+			DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32)
+				& ~FSL_DMA_MR_EMP_EN, 32);
+
+	if (fsl_chan->feature & FSL_DMA_CHAN_START_EXT)
+		mr_set |= FSL_DMA_MR_EMS_EN;
+	else
+		mr_set |= FSL_DMA_MR_CS;
+
+	DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr,
+			DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32)
+			| mr_set, 32);
+}
+
+static void dma_halt(struct fsl_dma_chan *fsl_chan)
+{
+	int i = 0;
+	DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr,
+		DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32) | FSL_DMA_MR_CA,
+		32);
+	DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr,
+		DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32) & ~(FSL_DMA_MR_CS
+		| FSL_DMA_MR_EMS_EN | FSL_DMA_MR_CA), 32);
+
+	while (!dma_is_idle(fsl_chan) && (i++ < 100))
+		udelay(10);
+	if (i >= 100 && !dma_is_idle(fsl_chan))
+		dev_err(fsl_chan->dev, "DMA halt timeout!\n");
+}
+
+static void set_ld_eol(struct fsl_dma_chan *fsl_chan,
+			struct fsl_desc_sw *desc)
+{
+	desc->hw.next_ln_addr = CPU_TO_DMA(fsl_chan,
+		DMA_TO_CPU(fsl_chan, desc->hw.next_ln_addr, 64)	| FSL_DMA_EOL,
+		64);
+}
+
+static void append_ld_queue(struct fsl_dma_chan *fsl_chan,
+		struct fsl_desc_sw *new_desc)
+{
+	struct fsl_desc_sw *queue_tail = to_fsl_desc(fsl_chan->ld_queue.prev);
+
+	if (list_empty(&fsl_chan->ld_queue))
+		return;
+
+	/* Link to the new descriptor physical address and
+	 * Enable End-of-segment interrupt for
+	 * the last link descriptor.
+	 * (the previous node's next link descriptor)
+	 *
+	 * For FSL_DMA_IP_83xx, the snoop enable bit need be set.
+	 */
+	queue_tail->hw.next_ln_addr = CPU_TO_DMA(fsl_chan,
+			new_desc->async_tx.phys | FSL_DMA_EOSIE |
+			(((fsl_chan->feature & FSL_DMA_IP_MASK)
+				== FSL_DMA_IP_83XX) ? FSL_DMA_SNEN : 0), 64);
+}
+
+/**
+ * fsl_chan_set_src_loop_size - Set source address hold transfer size
+ * @fsl_chan : Freescale DMA channel
+ * @size     : Address loop size, 0 for disable loop
+ *
+ * The set source address hold transfer size. The source
+ * address hold or loop transfer size is when the DMA transfer
+ * data from source address (SA), if the loop size is 4, the DMA will
+ * read data from SA, SA + 1, SA + 2, SA + 3, then loop back to SA,
+ * SA + 1 ... and so on.
+ */
+static void fsl_chan_set_src_loop_size(struct fsl_dma_chan *fsl_chan, int size)
+{
+	switch (size) {
+	case 0:
+		DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr,
+			DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32) &
+			(~FSL_DMA_MR_SAHE), 32);
+		break;
+	case 1:
+	case 2:
+	case 4:
+	case 8:
+		DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr,
+			DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32) |
+			FSL_DMA_MR_SAHE | (__ilog2(size) << 14),
+			32);
+		break;
+	}
+}
+
+/**
+ * fsl_chan_set_dest_loop_size - Set destination address hold transfer size
+ * @fsl_chan : Freescale DMA channel
+ * @size     : Address loop size, 0 for disable loop
+ *
+ * The set destination address hold transfer size. The destination
+ * address hold or loop transfer size is when the DMA transfer
+ * data to destination address (TA), if the loop size is 4, the DMA will
+ * write data to TA, TA + 1, TA + 2, TA + 3, then loop back to TA,
+ * TA + 1 ... and so on.
+ */
+static void fsl_chan_set_dest_loop_size(struct fsl_dma_chan *fsl_chan, int size)
+{
+	switch (size) {
+	case 0:
+		DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr,
+			DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32) &
+			(~FSL_DMA_MR_DAHE), 32);
+		break;
+	case 1:
+	case 2:
+	case 4:
+	case 8:
+		DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr,
+			DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32) |
+			FSL_DMA_MR_DAHE | (__ilog2(size) << 16),
+			32);
+		break;
+	}
+}
+
+/**
+ * fsl_chan_toggle_ext_pause - Toggle channel external pause status
+ * @fsl_chan : Freescale DMA channel
+ * @size     : Pause control size, 0 for disable external pause control.
+ *             The maximum is 1024.
+ *
+ * The Freescale DMA channel can be controlled by the external
+ * signal DREQ#. The pause control size is how many bytes are allowed
+ * to transfer before pausing the channel, after which a new assertion
+ * of DREQ# resumes channel operation.
+ */
+static void fsl_chan_toggle_ext_pause(struct fsl_dma_chan *fsl_chan, int size)
+{
+	if (size > 1024)
+		return;
+
+	if (size) {
+		DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr,
+			DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32)
+				| ((__ilog2(size) << 24) & 0x0f000000),
+			32);
+		fsl_chan->feature |= FSL_DMA_CHAN_PAUSE_EXT;
+	} else
+		fsl_chan->feature &= ~FSL_DMA_CHAN_PAUSE_EXT;
+}
+
+/**
+ * fsl_chan_toggle_ext_start - Toggle channel external start status
+ * @fsl_chan : Freescale DMA channel
+ * @enable   : 0 is disabled, 1 is enabled.
+ *
+ * If enable the external start, the channel can be started by an
+ * external DMA start pin. So the dma_start() does not start the
+ * transfer immediately. The DMA channel will wait for the
+ * control pin asserted.
+ */
+static void fsl_chan_toggle_ext_start(struct fsl_dma_chan *fsl_chan, int enable)
+{
+	if (enable)
+		fsl_chan->feature |= FSL_DMA_CHAN_START_EXT;
+	else
+		fsl_chan->feature &= ~FSL_DMA_CHAN_START_EXT;
+}
+
+static dma_cookie_t fsl_dma_tx_submit(struct dma_async_tx_descriptor *tx)
+{
+	struct fsl_desc_sw *desc = tx_to_fsl_desc(tx);
+	struct fsl_dma_chan *fsl_chan = to_fsl_chan(tx->chan);
+	unsigned long flags;
+	dma_cookie_t cookie;
+
+	/* cookie increment and adding to ld_queue must be atomic */
+	spin_lock_irqsave(&fsl_chan->desc_lock, flags);
+
+	cookie = fsl_chan->common.cookie;
+	cookie++;
+	if (cookie < 0)
+		cookie = 1;
+	desc->async_tx.cookie = cookie;
+	fsl_chan->common.cookie = desc->async_tx.cookie;
+
+	append_ld_queue(fsl_chan, desc);
+	list_splice_init(&desc->async_tx.tx_list, fsl_chan->ld_queue.prev);
+
+	spin_unlock_irqrestore(&fsl_chan->desc_lock, flags);
+
+	return cookie;
+}
+
+/**
+ * fsl_dma_alloc_descriptor - Allocate descriptor from channel's DMA pool.
+ * @fsl_chan : Freescale DMA channel
+ *
+ * Return - The descriptor allocated. NULL for failed.
+ */
+static struct fsl_desc_sw *fsl_dma_alloc_descriptor(
+					struct fsl_dma_chan *fsl_chan)
+{
+	dma_addr_t pdesc;
+	struct fsl_desc_sw *desc_sw;
+
+	desc_sw = dma_pool_alloc(fsl_chan->desc_pool, GFP_ATOMIC, &pdesc);
+	if (desc_sw) {
+		memset(desc_sw, 0, sizeof(struct fsl_desc_sw));
+		dma_async_tx_descriptor_init(&desc_sw->async_tx,
+						&fsl_chan->common);
+		desc_sw->async_tx.tx_submit = fsl_dma_tx_submit;
+		INIT_LIST_HEAD(&desc_sw->async_tx.tx_list);
+		desc_sw->async_tx.phys = pdesc;
+	}
+
+	return desc_sw;
+}
+
+
+/**
+ * fsl_dma_alloc_chan_resources - Allocate resources for DMA channel.
+ * @fsl_chan : Freescale DMA channel
+ *
+ * This function will create a dma pool for descriptor allocation.
+ *
+ * Return - The number of descriptors allocated.
+ */
+static int fsl_dma_alloc_chan_resources(struct dma_chan *chan)
+{
+	struct fsl_dma_chan *fsl_chan = to_fsl_chan(chan);
+	LIST_HEAD(tmp_list);
+
+	/* We need the descriptor to be aligned to 32bytes
+	 * for meeting FSL DMA specification requirement.
+	 */
+	fsl_chan->desc_pool = dma_pool_create("fsl_dma_engine_desc_pool",
+			fsl_chan->dev, sizeof(struct fsl_desc_sw),
+			32, 0);
+	if (!fsl_chan->desc_pool) {
+		dev_err(fsl_chan->dev, "No memory for channel %d "
+			"descriptor dma pool.\n", fsl_chan->id);
+		return 0;
+	}
+
+	return 1;
+}
+
+/**
+ * fsl_dma_free_chan_resources - Free all resources of the channel.
+ * @fsl_chan : Freescale DMA channel
+ */
+static void fsl_dma_free_chan_resources(struct dma_chan *chan)
+{
+	struct fsl_dma_chan *fsl_chan = to_fsl_chan(chan);
+	struct fsl_desc_sw *desc, *_desc;
+	unsigned long flags;
+
+	dev_dbg(fsl_chan->dev, "Free all channel resources.\n");
+	spin_lock_irqsave(&fsl_chan->desc_lock, flags);
+	list_for_each_entry_safe(desc, _desc, &fsl_chan->ld_queue, node) {
+#ifdef FSL_DMA_LD_DEBUG
+		dev_dbg(fsl_chan->dev,
+				"LD %p will be released.\n", desc);
+#endif
+		list_del(&desc->node);
+		/* free link descriptor */
+		dma_pool_free(fsl_chan->desc_pool, desc, desc->async_tx.phys);
+	}
+	spin_unlock_irqrestore(&fsl_chan->desc_lock, flags);
+	dma_pool_destroy(fsl_chan->desc_pool);
+}
+
+static struct dma_async_tx_descriptor *fsl_dma_prep_memcpy(
+	struct dma_chan *chan, dma_addr_t dma_dest, dma_addr_t dma_src,
+	size_t len, unsigned long flags)
+{
+	struct fsl_dma_chan *fsl_chan;
+	struct fsl_desc_sw *first = NULL, *prev = NULL, *new;
+	size_t copy;
+	LIST_HEAD(link_chain);
+
+	if (!chan)
+		return NULL;
+
+	if (!len)
+		return NULL;
+
+	fsl_chan = to_fsl_chan(chan);
+
+	do {
+
+		/* Allocate the link descriptor from DMA pool */
+		new = fsl_dma_alloc_descriptor(fsl_chan);
+		if (!new) {
+			dev_err(fsl_chan->dev,
+					"No free memory for link descriptor\n");
+			return NULL;
+		}
+#ifdef FSL_DMA_LD_DEBUG
+		dev_dbg(fsl_chan->dev, "new link desc alloc %p\n", new);
+#endif
+
+		copy = min(len, FSL_DMA_BCR_MAX_CNT);
+
+		set_desc_cnt(fsl_chan, &new->hw, copy);
+		set_desc_src(fsl_chan, &new->hw, dma_src);
+		set_desc_dest(fsl_chan, &new->hw, dma_dest);
+
+		if (!first)
+			first = new;
+		else
+			set_desc_next(fsl_chan, &prev->hw, new->async_tx.phys);
+
+		new->async_tx.cookie = 0;
+		new->async_tx.ack = 1;
+
+		prev = new;
+		len -= copy;
+		dma_src += copy;
+		dma_dest += copy;
+
+		/* Insert the link descriptor to the LD ring */
+		list_add_tail(&new->node, &first->async_tx.tx_list);
+	} while (len);
+
+	new->async_tx.ack = 0; /* client is in control of this ack */
+	new->async_tx.cookie = -EBUSY;
+
+	/* Set End-of-link to the last link descriptor of new list*/
+	set_ld_eol(fsl_chan, new);
+
+	return first ? &first->async_tx : NULL;
+}
+
+/**
+ * fsl_dma_update_completed_cookie - Update the completed cookie.
+ * @fsl_chan : Freescale DMA channel
+ */
+static void fsl_dma_update_completed_cookie(struct fsl_dma_chan *fsl_chan)
+{
+	struct fsl_desc_sw *cur_desc, *desc;
+	dma_addr_t ld_phy;
+
+	ld_phy = get_cdar(fsl_chan) & FSL_DMA_NLDA_MASK;
+
+	if (ld_phy) {
+		cur_desc = NULL;
+		list_for_each_entry(desc, &fsl_chan->ld_queue, node)
+			if (desc->async_tx.phys == ld_phy) {
+				cur_desc = desc;
+				break;
+			}
+
+		if (cur_desc && cur_desc->async_tx.cookie) {
+			if (dma_is_idle(fsl_chan))
+				fsl_chan->completed_cookie =
+					cur_desc->async_tx.cookie;
+			else
+				fsl_chan->completed_cookie =
+					cur_desc->async_tx.cookie - 1;
+		}
+	}
+}
+
+/**
+ * fsl_chan_ld_cleanup - Clean up link descriptors
+ * @fsl_chan : Freescale DMA channel
+ *
+ * This function clean up the ld_queue of DMA channel.
+ * If 'in_intr' is set, the function will move the link descriptor to
+ * the recycle list. Otherwise, free it directly.
+ */
+static void fsl_chan_ld_cleanup(struct fsl_dma_chan *fsl_chan)
+{
+	struct fsl_desc_sw *desc, *_desc;
+	unsigned long flags;
+
+	spin_lock_irqsave(&fsl_chan->desc_lock, flags);
+
+	fsl_dma_update_completed_cookie(fsl_chan);
+	dev_dbg(fsl_chan->dev, "chan completed_cookie = %d\n",
+			fsl_chan->completed_cookie);
+	list_for_each_entry_safe(desc, _desc, &fsl_chan->ld_queue, node) {
+		dma_async_tx_callback callback;
+		void *callback_param;
+
+		if (dma_async_is_complete(desc->async_tx.cookie,
+			    fsl_chan->completed_cookie, fsl_chan->common.cookie)
+				== DMA_IN_PROGRESS)
+			break;
+
+		callback = desc->async_tx.callback;
+		callback_param = desc->async_tx.callback_param;
+
+		/* Remove from ld_queue list */
+		list_del(&desc->node);
+
+		dev_dbg(fsl_chan->dev, "link descriptor %p will be recycle.\n",
+				desc);
+		dma_pool_free(fsl_chan->desc_pool, desc, desc->async_tx.phys);
+
+		/* Run the link descriptor callback function */
+		if (callback) {
+			spin_unlock_irqrestore(&fsl_chan->desc_lock, flags);
+			dev_dbg(fsl_chan->dev, "link descriptor %p callback\n",
+					desc);
+			callback(callback_param);
+			spin_lock_irqsave(&fsl_chan->desc_lock, flags);
+		}
+	}
+	spin_unlock_irqrestore(&fsl_chan->desc_lock, flags);
+}
+
+/**
+ * fsl_chan_xfer_ld_queue - Transfer link descriptors in channel ld_queue.
+ * @fsl_chan : Freescale DMA channel
+ */
+static void fsl_chan_xfer_ld_queue(struct fsl_dma_chan *fsl_chan)
+{
+	struct list_head *ld_node;
+	dma_addr_t next_dest_addr;
+	unsigned long flags;
+
+	if (!dma_is_idle(fsl_chan))
+		return;
+
+	dma_halt(fsl_chan);
+
+	/* If there are some link descriptors
+	 * not transfered in queue. We need to start it.
+	 */
+	spin_lock_irqsave(&fsl_chan->desc_lock, flags);
+
+	/* Find the first un-transfer desciptor */
+	for (ld_node = fsl_chan->ld_queue.next;
+		(ld_node != &fsl_chan->ld_queue)
+			&& (dma_async_is_complete(
+				to_fsl_desc(ld_node)->async_tx.cookie,
+				fsl_chan->completed_cookie,
+				fsl_chan->common.cookie) == DMA_SUCCESS);
+		ld_node = ld_node->next);
+
+	spin_unlock_irqrestore(&fsl_chan->desc_lock, flags);
+
+	if (ld_node != &fsl_chan->ld_queue) {
+		/* Get the ld start address from ld_queue */
+		next_dest_addr = to_fsl_desc(ld_node)->async_tx.phys;
+		dev_dbg(fsl_chan->dev, "xfer LDs staring from 0x%016llx\n",
+				(u64)next_dest_addr);
+		set_cdar(fsl_chan, next_dest_addr);
+		dma_start(fsl_chan);
+	} else {
+		set_cdar(fsl_chan, 0);
+		set_ndar(fsl_chan, 0);
+	}
+}
+
+/**
+ * fsl_dma_memcpy_issue_pending - Issue the DMA start command
+ * @fsl_chan : Freescale DMA channel
+ */
+static void fsl_dma_memcpy_issue_pending(struct dma_chan *chan)
+{
+	struct fsl_dma_chan *fsl_chan = to_fsl_chan(chan);
+
+#ifdef FSL_DMA_LD_DEBUG
+	struct fsl_desc_sw *ld;
+	unsigned long flags;
+
+	spin_lock_irqsave(&fsl_chan->desc_lock, flags);
+	if (list_empty(&fsl_chan->ld_queue)) {
+		spin_unlock_irqrestore(&fsl_chan->desc_lock, flags);
+		return;
+	}
+
+	dev_dbg(fsl_chan->dev, "--memcpy issue--\n");
+	list_for_each_entry(ld, &fsl_chan->ld_queue, node) {
+		int i;
+		dev_dbg(fsl_chan->dev, "Ch %d, LD %08x\n",
+				fsl_chan->id, ld->async_tx.phys);
+		for (i = 0; i < 8; i++)
+			dev_dbg(fsl_chan->dev, "LD offset %d: %08x\n",
+					i, *(((u32 *)&ld->hw) + i));
+	}
+	dev_dbg(fsl_chan->dev, "----------------\n");
+	spin_unlock_irqrestore(&fsl_chan->desc_lock, flags);
+#endif
+
+	fsl_chan_xfer_ld_queue(fsl_chan);
+}
+
+static void fsl_dma_dependency_added(struct dma_chan *chan)
+{
+	struct fsl_dma_chan *fsl_chan = to_fsl_chan(chan);
+
+	fsl_chan_ld_cleanup(fsl_chan);
+}
+
+/**
+ * fsl_dma_is_complete - Determine the DMA status
+ * @fsl_chan : Freescale DMA channel
+ */
+static enum dma_status fsl_dma_is_complete(struct dma_chan *chan,
+					dma_cookie_t cookie,
+					dma_cookie_t *done,
+					dma_cookie_t *used)
+{
+	struct fsl_dma_chan *fsl_chan = to_fsl_chan(chan);
+	dma_cookie_t last_used;
+	dma_cookie_t last_complete;
+
+	fsl_chan_ld_cleanup(fsl_chan);
+
+	last_used = chan->cookie;
+	last_complete = fsl_chan->completed_cookie;
+
+	if (done)
+		*done = last_complete;
+
+	if (used)
+		*used = last_used;
+
+	return dma_async_is_complete(cookie, last_complete, last_used);
+}
+
+static irqreturn_t fsl_dma_chan_do_interrupt(int irq, void *data)
+{
+	struct fsl_dma_chan *fsl_chan = (struct fsl_dma_chan *)data;
+	dma_addr_t stat;
+
+	stat = get_sr(fsl_chan);
+	dev_dbg(fsl_chan->dev, "event: channel %d, stat = 0x%x\n",
+						fsl_chan->id, stat);
+	set_sr(fsl_chan, stat);		/* Clear the event register */
+
+	stat &= ~(FSL_DMA_SR_CB | FSL_DMA_SR_CH);
+	if (!stat)
+		return IRQ_NONE;
+
+	if (stat & FSL_DMA_SR_TE)
+		dev_err(fsl_chan->dev, "Transfer Error!\n");
+
+	/* If the link descriptor segment transfer finishes,
+	 * we will recycle the used descriptor.
+	 */
+	if (stat & FSL_DMA_SR_EOSI) {
+		dev_dbg(fsl_chan->dev, "event: End-of-segments INT\n");
+		dev_dbg(fsl_chan->dev, "event: clndar 0x%016llx, "
+				"nlndar 0x%016llx\n", (u64)get_cdar(fsl_chan),
+				(u64)get_ndar(fsl_chan));
+		stat &= ~FSL_DMA_SR_EOSI;
+	}
+
+	/* If it current transfer is the end-of-transfer,
+	 * we should clear the Channel Start bit for
+	 * prepare next transfer.
+	 */
+	if (stat & (FSL_DMA_SR_EOLNI | FSL_DMA_SR_EOCDI)) {
+		dev_dbg(fsl_chan->dev, "event: End-of-link INT\n");
+		stat &= ~FSL_DMA_SR_EOLNI;
+		fsl_chan_xfer_ld_queue(fsl_chan);
+	}
+
+	if (stat)
+		dev_dbg(fsl_chan->dev, "event: unhandled sr 0x%02x\n",
+					stat);
+
+	dev_dbg(fsl_chan->dev, "event: Exit\n");
+	tasklet_schedule(&fsl_chan->tasklet);
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t fsl_dma_do_interrupt(int irq, void *data)
+{
+	struct fsl_dma_device *fdev = (struct fsl_dma_device *)data;
+	u32 gsr;
+	int ch_nr;
+
+	gsr = (fdev->feature & FSL_DMA_BIG_ENDIAN) ? in_be32(fdev->reg_base)
+			: in_le32(fdev->reg_base);
+	ch_nr = (32 - ffs(gsr)) / 8;
+
+	return fdev->chan[ch_nr] ? fsl_dma_chan_do_interrupt(irq,
+			fdev->chan[ch_nr]) : IRQ_NONE;
+}
+
+static void dma_do_tasklet(unsigned long data)
+{
+	struct fsl_dma_chan *fsl_chan = (struct fsl_dma_chan *)data;
+	fsl_chan_ld_cleanup(fsl_chan);
+}
+
+static void fsl_dma_callback_test(struct fsl_dma_chan *fsl_chan)
+{
+	if (fsl_chan)
+		dev_info(fsl_chan->dev, "selftest: callback is ok!\n");
+}
+
+static int fsl_dma_self_test(struct fsl_dma_chan *fsl_chan)
+{
+	struct dma_chan *chan;
+	int err = 0;
+	dma_addr_t dma_dest, dma_src;
+	dma_cookie_t cookie;
+	u8 *src, *dest;
+	int i;
+	size_t test_size;
+	struct dma_async_tx_descriptor *tx1, *tx2, *tx3;
+
+	test_size = 4096;
+
+	src = kmalloc(test_size * 2, GFP_KERNEL);
+	if (!src) {
+		dev_err(fsl_chan->dev,
+				"selftest: Cannot alloc memory for test!\n");
+		err = -ENOMEM;
+		goto out;
+	}
+
+	dest = src + test_size;
+
+	for (i = 0; i < test_size; i++)
+		src[i] = (u8) i;
+
+	chan = &fsl_chan->common;
+
+	if (fsl_dma_alloc_chan_resources(chan) < 1) {
+		dev_err(fsl_chan->dev,
+				"selftest: Cannot alloc resources for DMA\n");
+		err = -ENODEV;
+		goto out;
+	}
+
+	/* TX 1 */
+	dma_src = dma_map_single(fsl_chan->dev, src, test_size / 2,
+				 DMA_TO_DEVICE);
+	dma_dest = dma_map_single(fsl_chan->dev, dest, test_size / 2,
+				  DMA_FROM_DEVICE);
+	tx1 = fsl_dma_prep_memcpy(chan, dma_dest, dma_src, test_size / 2, 0);
+	async_tx_ack(tx1);
+
+	cookie = fsl_dma_tx_submit(tx1);
+	fsl_dma_memcpy_issue_pending(chan);
+	msleep(2);
+
+	if (fsl_dma_is_complete(chan, cookie, NULL, NULL) != DMA_SUCCESS) {
+		dev_err(fsl_chan->dev, "selftest: Time out!\n");
+		err = -ENODEV;
+		goto out;
+	}
+
+	/* Test free and re-alloc channel resources */
+	fsl_dma_free_chan_resources(chan);
+
+	if (fsl_dma_alloc_chan_resources(chan) < 1) {
+		dev_err(fsl_chan->dev,
+				"selftest: Cannot alloc resources for DMA\n");
+		err = -ENODEV;
+		goto free_resources;
+	}
+
+	/* Continue to test
+	 * TX 2
+	 */
+	dma_src = dma_map_single(fsl_chan->dev, src + test_size / 2,
+					test_size / 4, DMA_TO_DEVICE);
+	dma_dest = dma_map_single(fsl_chan->dev, dest + test_size / 2,
+					test_size / 4, DMA_FROM_DEVICE);
+	tx2 = fsl_dma_prep_memcpy(chan, dma_dest, dma_src, test_size / 4, 0);
+	async_tx_ack(tx2);
+
+	/* TX 3 */
+	dma_src = dma_map_single(fsl_chan->dev, src + test_size * 3 / 4,
+					test_size / 4, DMA_TO_DEVICE);
+	dma_dest = dma_map_single(fsl_chan->dev, dest + test_size * 3 / 4,
+					test_size / 4, DMA_FROM_DEVICE);
+	tx3 = fsl_dma_prep_memcpy(chan, dma_dest, dma_src, test_size / 4, 0);
+	async_tx_ack(tx3);
+
+	/* Test exchanging the prepared tx sort */
+	cookie = fsl_dma_tx_submit(tx3);
+	cookie = fsl_dma_tx_submit(tx2);
+
+#ifdef FSL_DMA_CALLBACKTEST
+	if (dma_has_cap(DMA_INTERRUPT, ((struct fsl_dma_device *)
+	    dev_get_drvdata(fsl_chan->dev->parent))->common.cap_mask)) {
+		tx3->callback = fsl_dma_callback_test;
+		tx3->callback_param = fsl_chan;
+	}
+#endif
+	fsl_dma_memcpy_issue_pending(chan);
+	msleep(2);
+
+	if (fsl_dma_is_complete(chan, cookie, NULL, NULL) != DMA_SUCCESS) {
+		dev_err(fsl_chan->dev, "selftest: Time out!\n");
+		err = -ENODEV;
+		goto free_resources;
+	}
+
+	err = memcmp(src, dest, test_size);
+	if (err) {
+		for (i = 0; (*(src + i) == *(dest + i)) && (i < test_size);
+				i++);
+		dev_err(fsl_chan->dev, "selftest: Test failed, data %d/%d is "
+				"error! src 0x%x, dest 0x%x\n",
+				i, test_size, *(src + i), *(dest + i));
+	}
+
+free_resources:
+	fsl_dma_free_chan_resources(chan);
+out:
+	kfree(src);
+	return err;
+}
+
+static int __devinit of_fsl_dma_chan_probe(struct of_device *dev,
+			const struct of_device_id *match)
+{
+	struct fsl_dma_device *fdev;
+	struct fsl_dma_chan *new_fsl_chan;
+	int err;
+
+	fdev = dev_get_drvdata(dev->dev.parent);
+	BUG_ON(!fdev);
+
+	/* alloc channel */
+	new_fsl_chan = kzalloc(sizeof(struct fsl_dma_chan), GFP_KERNEL);
+	if (!new_fsl_chan) {
+		dev_err(&dev->dev, "No free memory for allocating "
+				"dma channels!\n");
+		err = -ENOMEM;
+		goto err;
+	}
+
+	/* get dma channel register base */
+	err = of_address_to_resource(dev->node, 0, &new_fsl_chan->reg);
+	if (err) {
+		dev_err(&dev->dev, "Can't get %s property 'reg'\n",
+				dev->node->full_name);
+		goto err;
+	}
+
+	new_fsl_chan->feature = *(u32 *)match->data;
+
+	if (!fdev->feature)
+		fdev->feature = new_fsl_chan->feature;
+
+	/* If the DMA device's feature is different than its channels',
+	 * report the bug.
+	 */
+	WARN_ON(fdev->feature != new_fsl_chan->feature);
+
+	new_fsl_chan->dev = &dev->dev;
+	new_fsl_chan->reg_base = ioremap(new_fsl_chan->reg.start,
+			new_fsl_chan->reg.end - new_fsl_chan->reg.start + 1);
+
+	new_fsl_chan->id = ((new_fsl_chan->reg.start - 0x100) & 0xfff) >> 7;
+	if (new_fsl_chan->id > FSL_DMA_MAX_CHANS_PER_DEVICE) {
+		dev_err(&dev->dev, "There is no %d channel!\n",
+				new_fsl_chan->id);
+		err = -EINVAL;
+		goto err;
+	}
+	fdev->chan[new_fsl_chan->id] = new_fsl_chan;
+	tasklet_init(&new_fsl_chan->tasklet, dma_do_tasklet,
+			(unsigned long)new_fsl_chan);
+
+	/* Init the channel */
+	dma_init(new_fsl_chan);
+
+	/* Clear cdar registers */
+	set_cdar(new_fsl_chan, 0);
+
+	switch (new_fsl_chan->feature & FSL_DMA_IP_MASK) {
+	case FSL_DMA_IP_85XX:
+		new_fsl_chan->toggle_ext_start = fsl_chan_toggle_ext_start;
+		new_fsl_chan->toggle_ext_pause = fsl_chan_toggle_ext_pause;
+	case FSL_DMA_IP_83XX:
+		new_fsl_chan->set_src_loop_size = fsl_chan_set_src_loop_size;
+		new_fsl_chan->set_dest_loop_size = fsl_chan_set_dest_loop_size;
+	}
+
+	spin_lock_init(&new_fsl_chan->desc_lock);
+	INIT_LIST_HEAD(&new_fsl_chan->ld_queue);
+
+	new_fsl_chan->common.device = &fdev->common;
+
+	/* Add the channel to DMA device channel list */
+	list_add_tail(&new_fsl_chan->common.device_node,
+			&fdev->common.channels);
+	fdev->common.chancnt++;
+
+	new_fsl_chan->irq = irq_of_parse_and_map(dev->node, 0);
+	if (new_fsl_chan->irq != NO_IRQ) {
+		err = request_irq(new_fsl_chan->irq,
+					&fsl_dma_chan_do_interrupt, IRQF_SHARED,
+					"fsldma-channel", new_fsl_chan);
+		if (err) {
+			dev_err(&dev->dev, "DMA channel %s request_irq error "
+				"with return %d\n", dev->node->full_name, err);
+			goto err;
+		}
+	}
+
+#ifdef CONFIG_FSL_DMA_SELFTEST
+	err = fsl_dma_self_test(new_fsl_chan);
+	if (err)
+		goto err;
+#endif
+
+	dev_info(&dev->dev, "#%d (%s), irq %d\n", new_fsl_chan->id,
+				match->compatible, new_fsl_chan->irq);
+
+	return 0;
+err:
+	dma_halt(new_fsl_chan);
+	iounmap(new_fsl_chan->reg_base);
+	free_irq(new_fsl_chan->irq, new_fsl_chan);
+	list_del(&new_fsl_chan->common.device_node);
+	kfree(new_fsl_chan);
+	return err;
+}
+
+const u32 mpc8540_dma_ip_feature = FSL_DMA_IP_85XX | FSL_DMA_BIG_ENDIAN;
+const u32 mpc8349_dma_ip_feature = FSL_DMA_IP_83XX | FSL_DMA_LITTLE_ENDIAN;
+
+static struct of_device_id of_fsl_dma_chan_ids[] = {
+	{
+		.compatible = "fsl,mpc8540-dma-channel",
+		.data = (void *)&mpc8540_dma_ip_feature,
+	},
+	{
+		.compatible = "fsl,mpc8349-dma-channel",
+		.data = (void *)&mpc8349_dma_ip_feature,
+	},
+	{}
+};
+
+static struct of_platform_driver of_fsl_dma_chan_driver = {
+	.name = "of-fsl-dma-channel",
+	.match_table = of_fsl_dma_chan_ids,
+	.probe = of_fsl_dma_chan_probe,
+};
+
+static __init int of_fsl_dma_chan_init(void)
+{
+	return of_register_platform_driver(&of_fsl_dma_chan_driver);
+}
+
+static int __devinit of_fsl_dma_probe(struct of_device *dev,
+			const struct of_device_id *match)
+{
+	int err;
+	unsigned int irq;
+	struct fsl_dma_device *fdev;
+
+	fdev = kzalloc(sizeof(struct fsl_dma_device), GFP_KERNEL);
+	if (!fdev) {
+		dev_err(&dev->dev, "No enough memory for 'priv'\n");
+		err = -ENOMEM;
+		goto err;
+	}
+	fdev->dev = &dev->dev;
+	INIT_LIST_HEAD(&fdev->common.channels);
+
+	/* get DMA controller register base */
+	err = of_address_to_resource(dev->node, 0, &fdev->reg);
+	if (err) {
+		dev_err(&dev->dev, "Can't get %s property 'reg'\n",
+				dev->node->full_name);
+		goto err;
+	}
+
+	dev_info(&dev->dev, "Probe the Freescale DMA driver for %s "
+			"controller at 0x%08x...\n",
+			match->compatible, fdev->reg.start);
+	fdev->reg_base = ioremap(fdev->reg.start, fdev->reg.end
+						- fdev->reg.start + 1);
+
+	dma_cap_set(DMA_MEMCPY, fdev->common.cap_mask);
+	dma_cap_set(DMA_INTERRUPT, fdev->common.cap_mask);
+	fdev->common.device_alloc_chan_resources = fsl_dma_alloc_chan_resources;
+	fdev->common.device_free_chan_resources = fsl_dma_free_chan_resources;
+	fdev->common.device_prep_dma_memcpy = fsl_dma_prep_memcpy;
+	fdev->common.device_is_tx_complete = fsl_dma_is_complete;
+	fdev->common.device_issue_pending = fsl_dma_memcpy_issue_pending;
+	fdev->common.device_dependency_added = fsl_dma_dependency_added;
+	fdev->common.dev = &dev->dev;
+
+	irq = irq_of_parse_and_map(dev->node, 0);
+	if (irq != NO_IRQ) {
+		err = request_irq(irq, &fsl_dma_do_interrupt, IRQF_SHARED,
+					"fsldma-device", fdev);
+		if (err) {
+			dev_err(&dev->dev, "DMA device request_irq error "
+				"with return %d\n", err);
+			goto err;
+		}
+	}
+
+	dev_set_drvdata(&(dev->dev), fdev);
+	of_platform_bus_probe(dev->node, of_fsl_dma_chan_ids, &dev->dev);
+
+	dma_async_device_register(&fdev->common);
+	return 0;
+
+err:
+	iounmap(fdev->reg_base);
+	kfree(fdev);
+	return err;
+}
+
+static struct of_device_id of_fsl_dma_ids[] = {
+	{ .compatible = "fsl,mpc8540-dma", },
+	{ .compatible = "fsl,mpc8349-dma", },
+	{}
+};
+
+static struct of_platform_driver of_fsl_dma_driver = {
+	.name = "of-fsl-dma",
+	.match_table = of_fsl_dma_ids,
+	.probe = of_fsl_dma_probe,
+};
+
+static __init int of_fsl_dma_init(void)
+{
+	return of_register_platform_driver(&of_fsl_dma_driver);
+}
+
+subsys_initcall(of_fsl_dma_chan_init);
+subsys_initcall(of_fsl_dma_init);

drivers/dma/fsldma.h

+/*
+ * Copyright (C) 2007 Freescale Semiconductor, Inc. All rights reserved.
+ *
+ * Author:
+ *   Zhang Wei <wei.zhang@freescale.com>, Jul 2007
+ *   Ebony Zhu <ebony.zhu@freescale.com>, May 2007
+ *
+ * This is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ */
+#ifndef __DMA_FSLDMA_H
+#define __DMA_FSLDMA_H
+
+#include <linux/device.h>
+#include <linux/dmapool.h>
+#include <linux/dmaengine.h>
+
+/* Define data structures needed by Freescale
+ * MPC8540 and MPC8349 DMA controller.
+ */
+#define FSL_DMA_MR_CS		0x00000001
+#define FSL_DMA_MR_CC		0x00000002
+#define FSL_DMA_MR_CA		0x00000008
+#define FSL_DMA_MR_EIE		0x00000040
+#define FSL_DMA_MR_XFE		0x00000020
+#define FSL_DMA_MR_EOLNIE	0x00000100
+#define FSL_DMA_MR_EOLSIE	0x00000080
+#define FSL_DMA_MR_EOSIE	0x00000200
+#define FSL_DMA_MR_CDSM		0x00000010
+#define FSL_DMA_MR_CTM		0x00000004
+#define FSL_DMA_MR_EMP_EN	0x00200000
+#define FSL_DMA_MR_EMS_EN	0x00040000
+#define FSL_DMA_MR_DAHE		0x00002000
+#define FSL_DMA_MR_SAHE		0x00001000
+
+/* Special MR definition for MPC8349 */
+#define FSL_DMA_MR_EOTIE	0x00000080
+
+#define FSL_DMA_SR_CH		0x00000020
+#define FSL_DMA_SR_CB		0x00000004
+#define FSL_DMA_SR_TE		0x00000080
+#define FSL_DMA_SR_EOSI		0x00000002
+#define FSL_DMA_SR_EOLSI	0x00000001
+#define FSL_DMA_SR_EOCDI	0x00000001
+#define FSL_DMA_SR_EOLNI	0x00000008
+
+#define FSL_DMA_SATR_SBPATMU			0x20000000
+#define FSL_DMA_SATR_STRANSINT_RIO		0x00c00000
+#define FSL_DMA_SATR_SREADTYPE_SNOOP_READ	0x00050000
+#define FSL_DMA_SATR_SREADTYPE_BP_IORH		0x00020000
+#define FSL_DMA_SATR_SREADTYPE_BP_NREAD		0x00040000
+#define FSL_DMA_SATR_SREADTYPE_BP_MREAD		0x00070000
+
+#define FSL_DMA_DATR_DBPATMU			0x20000000
+#define FSL_DMA_DATR_DTRANSINT_RIO		0x00c00000
+#define FSL_DMA_DATR_DWRITETYPE_SNOOP_WRITE	0x00050000
+#define FSL_DMA_DATR_DWRITETYPE_BP_FLUSH	0x00010000
+
+#define FSL_DMA_EOL		((u64)0x1)
+#define FSL_DMA_SNEN		((u64)0x10)
+#define FSL_DMA_EOSIE		0x8
+#define FSL_DMA_NLDA_MASK	(~(u64)0x1f)
+
+#define FSL_DMA_BCR_MAX_CNT	0x03ffffffu
+
+#define FSL_DMA_DGSR_TE		0x80
+#define FSL_DMA_DGSR_CH		0x20
+#define FSL_DMA_DGSR_PE		0x10
+#define FSL_DMA_DGSR_EOLNI	0x08
+#define FSL_DMA_DGSR_CB		0x04
+#define FSL_DMA_DGSR_EOSI	0x02
+#define FSL_DMA_DGSR_EOLSI	0x01
+
+struct fsl_dma_ld_hw {
+	u64 __bitwise	src_addr;
+	u64 __bitwise	dst_addr;
+	u64 __bitwise	next_ln_addr;
+	u32 __bitwise	count;
+	u32 __bitwise	reserve;
+} __attribute__((aligned(32)));
+
+struct fsl_desc_sw {
+	struct fsl_dma_ld_hw hw;
+	struct list_head node;
+	struct dma_async_tx_descriptor async_tx;
+	struct list_head *ld;
+	void *priv;
+} __attribute__((aligned(32)));
+
+struct fsl_dma_chan_regs {
+	u32 __bitwise	mr;	/* 0x00 - Mode Register */
+	u32 __bitwise	sr;	/* 0x04 - Status Register */
+	u64 __bitwise	cdar;	/* 0x08 - Current descriptor address register */
+	u64 __bitwise	sar;	/* 0x10 - Source Address Register */
+	u64 __bitwise	dar;	/* 0x18 - Destination Address Register */
+	u32 __bitwise	bcr;	/* 0x20 - Byte Count Register */
+	u64 __bitwise	ndar;	/* 0x24 - Next Descriptor Address Register */
+};
+
+struct fsl_dma_chan;
+#define FSL_DMA_MAX_CHANS_PER_DEVICE 4
+
+struct fsl_dma_device {
+	void __iomem *reg_base;	/* DGSR register base */
+	struct resource reg;	/* Resource for register */
+	struct device *dev;
+	struct dma_device common;
+	struct fsl_dma_chan *chan[FSL_DMA_MAX_CHANS_PER_DEVICE];
+	u32 feature;		/* The same as DMA channels */
+};
+
+/* Define macros for fsl_dma_chan->feature property */
+#define FSL_DMA_LITTLE_ENDIAN	0x00000000
+#define FSL_DMA_BIG_ENDIAN	0x00000001
+
+#define FSL_DMA_IP_MASK		0x00000ff0
+#define FSL_DMA_IP_85XX		0x00000010
+#define FSL_DMA_IP_83XX		0x00000020
+
+#define FSL_DMA_CHAN_PAUSE_EXT	0x00001000
+#define FSL_DMA_CHAN_START_EXT	0x00002000
+
+struct fsl_dma_chan {
+	struct fsl_dma_chan_regs __iomem *reg_base;
+	dma_cookie_t completed_cookie;	/* The maximum cookie completed */
+	spinlock_t desc_lock;		/* Descriptor operation lock */
+	struct list_head ld_queue;	/* Link descriptors queue */
+	struct dma_chan common;		/* DMA common channel */
+	struct dma_pool *desc_pool;	/* Descriptors pool */
+	struct device *dev;		/* Channel device */
+	struct resource reg;		/* Resource for register */
+	int irq;			/* Channel IRQ */
+	int id;				/* Raw id of this channel */
+	struct tasklet_struct tasklet;
+	u32 feature;
+
+	void (*toggle_ext_pause)(struct fsl_dma_chan *fsl_chan, int size);
+	void (*toggle_ext_start)(struct fsl_dma_chan *fsl_chan, int enable);
+	void (*set_src_loop_size)(struct fsl_dma_chan *fsl_chan, int size);
+	void (*set_dest_loop_size)(struct fsl_dma_chan *fsl_chan, int size);
+};
+
+#define to_fsl_chan(chan) container_of(chan, struct fsl_dma_chan, common)
+#define to_fsl_desc(lh) container_of(lh, struct fsl_desc_sw, node)
+#define tx_to_fsl_desc(tx) container_of(tx, struct fsl_desc_sw, async_tx)
+
+#ifndef __powerpc64__
+static u64 in_be64(const u64 __iomem *addr)
+{
+	return ((u64)in_be32((u32 *)addr) << 32) | (in_be32((u32 *)addr + 1));
+}
+
+static void out_be64(u64 __iomem *addr, u64 val)
+{
+	out_be32((u32 *)addr, val >> 32);
+	out_be32((u32 *)addr + 1, (u32)val);
+}
+
+/* There is no asm instructions for 64 bits reverse loads and stores */
+static u64 in_le64(const u64 __iomem *addr)
+{
+	return ((u64)in_le32((u32 *)addr + 1) << 32) | (in_le32((u32 *)addr));
+}
+
+static void out_le64(u64 __iomem *addr, u64 val)
+{
+	out_le32((u32 *)addr + 1, val >> 32);
+	out_le32((u32 *)addr, (u32)val);
+}
+#endif
+
+#define DMA_IN(fsl_chan, addr, width)					\
+		(((fsl_chan)->feature & FSL_DMA_BIG_ENDIAN) ?		\
+			in_be##width(addr) : in_le##width(addr))
+#define DMA_OUT(fsl_chan, addr, val, width)				\
+		(((fsl_chan)->feature & FSL_DMA_BIG_ENDIAN) ?		\
+			out_be##width(addr, val) : out_le##width(addr, val))
+
+#define DMA_TO_CPU(fsl_chan, d, width)					\
+		(((fsl_chan)->feature & FSL_DMA_BIG_ENDIAN) ?		\
+			be##width##_to_cpu(d) :	le##width##_to_cpu(d))
+#define CPU_TO_DMA(fsl_chan, c, width)					\
+		(((fsl_chan)->feature & FSL_DMA_BIG_ENDIAN) ?		\
+			cpu_to_be##width(c) : cpu_to_le##width(c))
+
+#endif	/* __DMA_FSLDMA_H */

drivers/dma/ioat_dma.c

@@ -714,6 +714,7 @@ static struct dma_async_tx_descriptor *ioat1_dma_prep_memcpy(
 		new->len = len;
 		new->dst = dma_dest;
 		new->src = dma_src;
+		new->async_tx.ack = 0;
 		return &new->async_tx;
 	} else
 		return NULL;
@@ -741,6 +742,7 @@ static struct dma_async_tx_descriptor *ioat2_dma_prep_memcpy(
 		new->len = len;
 		new->dst = dma_dest;
 		new->src = dma_src;
+		new->async_tx.ack = 0;
 		return &new->async_tx;
 	} else
 		return NULL;

include/linux/dmaengine.h

@@ -366,7 +366,7 @@ __dma_has_cap(enum dma_transaction_type tx_type, dma_cap_mask_t *srcp)
  */
 static inline void dma_async_issue_pending(struct dma_chan *chan)
 {
-	return chan->device->device_issue_pending(chan);
+	chan->device->device_issue_pending(chan);
 }
 
 #define dma_async_memcpy_issue_pending(chan) dma_async_issue_pending(chan)