crypto: ccp - Register the CCP as a DMA resource

The CCP has the ability to provide DMA services to the
kernel using pass-through mode of the device. Register
these services as general purpose DMA channels.

Changes since v2:
- Add a Signed-off-by

Changes since v1:
- Allocate memory for a string in ccp_dmaengine_register
- Ensure register/unregister calls are properly ordered
- Verified all changed files are listed in the diffstat
- Undo some superfluous changes
- Added a cc:
Signed-off-by: Gary R Hook <gary.hook@amd.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

drivers/crypto/ccp/Kconfig

@@ -3,6 +3,7 @@ config CRYPTO_DEV_CCP_DD
 	depends on CRYPTO_DEV_CCP
 	default m
 	select HW_RANDOM
+	select DMA_ENGINE
 	select CRYPTO_SHA1
 	select CRYPTO_SHA256
 	help

drivers/crypto/ccp/Makefile

 obj-$(CONFIG_CRYPTO_DEV_CCP_DD) += ccp.o
-ccp-objs := ccp-dev.o ccp-ops.o ccp-dev-v3.o ccp-platform.o
+ccp-objs := ccp-dev.o \
+	    ccp-ops.o \
+	    ccp-dev-v3.o \
+	    ccp-platform.o \
+	    ccp-dmaengine.o
 ccp-$(CONFIG_PCI) += ccp-pci.o
 
 obj-$(CONFIG_CRYPTO_DEV_CCP_CRYPTO) += ccp-crypto.o

drivers/crypto/ccp/ccp-dev-v3.c

@@ -406,6 +406,11 @@ static int ccp_init(struct ccp_device *ccp)
 		goto e_kthread;
 	}
 
+	/* Register the DMA engine support */
+	ret = ccp_dmaengine_register(ccp);
+	if (ret)
+		goto e_hwrng;
+
 	ccp_add_device(ccp);
 
 	/* Enable interrupts */
@@ -413,6 +418,9 @@ static int ccp_init(struct ccp_device *ccp)
 
 	return 0;
 
+e_hwrng:
+	hwrng_unregister(&ccp->hwrng);
+
 e_kthread:
 	for (i = 0; i < ccp->cmd_q_count; i++)
 		if (ccp->cmd_q[i].kthread)
@@ -436,6 +444,9 @@ static void ccp_destroy(struct ccp_device *ccp)
 	/* Remove this device from the list of available units first */
 	ccp_del_device(ccp);
 
+	/* Unregister the DMA engine */
+	ccp_dmaengine_unregister(ccp);
+
 	/* Unregister the RNG */
 	hwrng_unregister(&ccp->hwrng);
 

drivers/crypto/ccp/ccp-dev.h

@@ -22,6 +22,9 @@
 #include <linux/dmapool.h>
 #include <linux/hw_random.h>
 #include <linux/bitops.h>
+#include <linux/interrupt.h>
+#include <linux/irqreturn.h>
+#include <linux/dmaengine.h>
 
 #define MAX_CCP_NAME_LEN		16
 #define MAX_DMAPOOL_NAME_LEN		32
@@ -167,6 +170,39 @@ extern struct ccp_vdata ccpv3;
 struct ccp_device;
 struct ccp_cmd;
 
+struct ccp_dma_cmd {
+	struct list_head entry;
+
+	struct ccp_cmd ccp_cmd;
+};
+
+struct ccp_dma_desc {
+	struct list_head entry;
+
+	struct ccp_device *ccp;
+
+	struct list_head pending;
+	struct list_head active;
+
+	enum dma_status status;
+	struct dma_async_tx_descriptor tx_desc;
+	size_t len;
+};
+
+struct ccp_dma_chan {
+	struct ccp_device *ccp;
+
+	spinlock_t lock;
+	struct list_head pending;
+	struct list_head active;
+	struct list_head complete;
+
+	struct tasklet_struct cleanup_tasklet;
+
+	enum dma_status status;
+	struct dma_chan dma_chan;
+};
+
 struct ccp_cmd_queue {
 	struct ccp_device *ccp;
 
@@ -260,6 +296,14 @@ struct ccp_device {
 	struct hwrng hwrng;
 	unsigned int hwrng_retries;
 
+	/*
+	 * Support for the CCP DMA capabilities
+	 */
+	struct dma_device dma_dev;
+	struct ccp_dma_chan *ccp_dma_chan;
+	struct kmem_cache *dma_cmd_cache;
+	struct kmem_cache *dma_desc_cache;
+
 	/*
 	 * A counter used to generate job-ids for cmds submitted to the CCP
 	 */
@@ -418,4 +462,7 @@ int ccp_cmd_queue_thread(void *data);
 
 int ccp_run_cmd(struct ccp_cmd_queue *cmd_q, struct ccp_cmd *cmd);
 
+int ccp_dmaengine_register(struct ccp_device *ccp);
+void ccp_dmaengine_unregister(struct ccp_device *ccp);
+
 #endif

drivers/crypto/ccp/ccp-dmaengine.c

+/*
+ * AMD Cryptographic Coprocessor (CCP) driver
+ *
+ * Copyright (C) 2016 Advanced Micro Devices, Inc.
+ *
+ * Author: Gary R Hook <gary.hook@amd.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/kernel.h>
+#include <linux/dmaengine.h>
+#include <linux/spinlock.h>
+#include <linux/mutex.h>
+#include <linux/ccp.h>
+
+#include "ccp-dev.h"
+#include "../../dma/dmaengine.h"
+
+#define CCP_DMA_WIDTH(_mask)		\
+({					\
+	u64 mask = _mask + 1;		\
+	(mask == 0) ? 64 : fls64(mask);	\
+})
+
+static void ccp_free_cmd_resources(struct ccp_device *ccp,
+				   struct list_head *list)
+{
+	struct ccp_dma_cmd *cmd, *ctmp;
+
+	list_for_each_entry_safe(cmd, ctmp, list, entry) {
+		list_del(&cmd->entry);
+		kmem_cache_free(ccp->dma_cmd_cache, cmd);
+	}
+}
+
+static void ccp_free_desc_resources(struct ccp_device *ccp,
+				    struct list_head *list)
+{
+	struct ccp_dma_desc *desc, *dtmp;
+
+	list_for_each_entry_safe(desc, dtmp, list, entry) {
+		ccp_free_cmd_resources(ccp, &desc->active);
+		ccp_free_cmd_resources(ccp, &desc->pending);
+
+		list_del(&desc->entry);
+		kmem_cache_free(ccp->dma_desc_cache, desc);
+	}
+}
+
+static void ccp_free_chan_resources(struct dma_chan *dma_chan)
+{
+	struct ccp_dma_chan *chan = container_of(dma_chan, struct ccp_dma_chan,
+						 dma_chan);
+	unsigned long flags;
+
+	dev_dbg(chan->ccp->dev, "%s - chan=%p\n", __func__, chan);
+
+	spin_lock_irqsave(&chan->lock, flags);
+
+	ccp_free_desc_resources(chan->ccp, &chan->complete);
+	ccp_free_desc_resources(chan->ccp, &chan->active);
+	ccp_free_desc_resources(chan->ccp, &chan->pending);
+
+	spin_unlock_irqrestore(&chan->lock, flags);
+}
+
+static void ccp_cleanup_desc_resources(struct ccp_device *ccp,
+				       struct list_head *list)
+{
+	struct ccp_dma_desc *desc, *dtmp;
+
+	list_for_each_entry_safe_reverse(desc, dtmp, list, entry) {
+		if (!async_tx_test_ack(&desc->tx_desc))
+			continue;
+
+		dev_dbg(ccp->dev, "%s - desc=%p\n", __func__, desc);
+
+		ccp_free_cmd_resources(ccp, &desc->active);
+		ccp_free_cmd_resources(ccp, &desc->pending);
+
+		list_del(&desc->entry);
+		kmem_cache_free(ccp->dma_desc_cache, desc);
+	}
+}
+
+static void ccp_do_cleanup(unsigned long data)
+{
+	struct ccp_dma_chan *chan = (struct ccp_dma_chan *)data;
+	unsigned long flags;
+
+	dev_dbg(chan->ccp->dev, "%s - chan=%s\n", __func__,
+		dma_chan_name(&chan->dma_chan));
+
+	spin_lock_irqsave(&chan->lock, flags);
+
+	ccp_cleanup_desc_resources(chan->ccp, &chan->complete);
+
+	spin_unlock_irqrestore(&chan->lock, flags);
+}
+
+static int ccp_issue_next_cmd(struct ccp_dma_desc *desc)
+{
+	struct ccp_dma_cmd *cmd;
+	int ret;
+
+	cmd = list_first_entry(&desc->pending, struct ccp_dma_cmd, entry);
+	list_move(&cmd->entry, &desc->active);
+
+	dev_dbg(desc->ccp->dev, "%s - tx %d, cmd=%p\n", __func__,
+		desc->tx_desc.cookie, cmd);
+
+	ret = ccp_enqueue_cmd(&cmd->ccp_cmd);
+	if (!ret || (ret == -EINPROGRESS) || (ret == -EBUSY))
+		return 0;
+
+	dev_dbg(desc->ccp->dev, "%s - error: ret=%d, tx %d, cmd=%p\n", __func__,
+		ret, desc->tx_desc.cookie, cmd);
+
+	return ret;
+}
+
+static void ccp_free_active_cmd(struct ccp_dma_desc *desc)
+{
+	struct ccp_dma_cmd *cmd;
+
+	cmd = list_first_entry_or_null(&desc->active, struct ccp_dma_cmd,
+				       entry);
+	if (!cmd)
+		return;
+
+	dev_dbg(desc->ccp->dev, "%s - freeing tx %d cmd=%p\n",
+		__func__, desc->tx_desc.cookie, cmd);
+
+	list_del(&cmd->entry);
+	kmem_cache_free(desc->ccp->dma_cmd_cache, cmd);
+}
+
+static struct ccp_dma_desc *__ccp_next_dma_desc(struct ccp_dma_chan *chan,
+						struct ccp_dma_desc *desc)
+{
+	/* Move current DMA descriptor to the complete list */
+	if (desc)
+		list_move(&desc->entry, &chan->complete);
+
+	/* Get the next DMA descriptor on the active list */
+	desc = list_first_entry_or_null(&chan->active, struct ccp_dma_desc,
+					entry);
+
+	return desc;
+}
+
+static struct ccp_dma_desc *ccp_handle_active_desc(struct ccp_dma_chan *chan,
+						   struct ccp_dma_desc *desc)
+{
+	struct dma_async_tx_descriptor *tx_desc;
+	unsigned long flags;
+
+	/* Loop over descriptors until one is found with commands */
+	do {
+		if (desc) {
+			/* Remove the DMA command from the list and free it */
+			ccp_free_active_cmd(desc);
+
+			if (!list_empty(&desc->pending)) {
+				/* No errors, keep going */
+				if (desc->status != DMA_ERROR)
+					return desc;
+
+				/* Error, free remaining commands and move on */
+				ccp_free_cmd_resources(desc->ccp,
+						       &desc->pending);
+			}
+
+			tx_desc = &desc->tx_desc;
+		} else {
+			tx_desc = NULL;
+		}
+
+		spin_lock_irqsave(&chan->lock, flags);
+
+		if (desc) {
+			if (desc->status != DMA_ERROR)
+				desc->status = DMA_COMPLETE;
+
+			dev_dbg(desc->ccp->dev,
+				"%s - tx %d complete, status=%u\n", __func__,
+				desc->tx_desc.cookie, desc->status);
+
+			dma_cookie_complete(tx_desc);
+		}
+
+		desc = __ccp_next_dma_desc(chan, desc);
+
+		spin_unlock_irqrestore(&chan->lock, flags);
+
+		if (tx_desc) {
+			if (tx_desc->callback &&
+			    (tx_desc->flags & DMA_PREP_INTERRUPT))
+				tx_desc->callback(tx_desc->callback_param);
+
+			dma_run_dependencies(tx_desc);
+		}
+	} while (desc);
+
+	return NULL;
+}
+
+static struct ccp_dma_desc *__ccp_pending_to_active(struct ccp_dma_chan *chan)
+{
+	struct ccp_dma_desc *desc;
+
+	if (list_empty(&chan->pending))
+		return NULL;
+
+	desc = list_empty(&chan->active)
+		? list_first_entry(&chan->pending, struct ccp_dma_desc, entry)
+		: NULL;
+
+	list_splice_tail_init(&chan->pending, &chan->active);
+
+	return desc;
+}
+
+static void ccp_cmd_callback(void *data, int err)
+{
+	struct ccp_dma_desc *desc = data;
+	struct ccp_dma_chan *chan;
+	int ret;
+
+	if (err == -EINPROGRESS)
+		return;
+
+	chan = container_of(desc->tx_desc.chan, struct ccp_dma_chan,
+			    dma_chan);
+
+	dev_dbg(chan->ccp->dev, "%s - tx %d callback, err=%d\n",
+		__func__, desc->tx_desc.cookie, err);
+
+	if (err)
+		desc->status = DMA_ERROR;
+
+	while (true) {
+		/* Check for DMA descriptor completion */
+		desc = ccp_handle_active_desc(chan, desc);
+
+		/* Don't submit cmd if no descriptor or DMA is paused */
+		if (!desc || (chan->status == DMA_PAUSED))
+			break;
+
+		ret = ccp_issue_next_cmd(desc);
+		if (!ret)
+			break;
+
+		desc->status = DMA_ERROR;
+	}
+
+	tasklet_schedule(&chan->cleanup_tasklet);
+}
+
+static dma_cookie_t ccp_tx_submit(struct dma_async_tx_descriptor *tx_desc)
+{
+	struct ccp_dma_desc *desc = container_of(tx_desc, struct ccp_dma_desc,
+						 tx_desc);
+	struct ccp_dma_chan *chan;
+	dma_cookie_t cookie;
+	unsigned long flags;
+
+	chan = container_of(tx_desc->chan, struct ccp_dma_chan, dma_chan);
+
+	spin_lock_irqsave(&chan->lock, flags);
+
+	cookie = dma_cookie_assign(tx_desc);
+	list_add_tail(&desc->entry, &chan->pending);
+
+	spin_unlock_irqrestore(&chan->lock, flags);
+
+	dev_dbg(chan->ccp->dev, "%s - added tx descriptor %d to pending list\n",
+		__func__, cookie);
+
+	return cookie;
+}
+
+static struct ccp_dma_cmd *ccp_alloc_dma_cmd(struct ccp_dma_chan *chan)
+{
+	struct ccp_dma_cmd *cmd;
+
+	cmd = kmem_cache_alloc(chan->ccp->dma_cmd_cache, GFP_NOWAIT);
+	if (cmd)
+		memset(cmd, 0, sizeof(*cmd));
+
+	return cmd;
+}
+
+static struct ccp_dma_desc *ccp_alloc_dma_desc(struct ccp_dma_chan *chan,
+					       unsigned long flags)
+{
+	struct ccp_dma_desc *desc;
+
+	desc = kmem_cache_alloc(chan->ccp->dma_desc_cache, GFP_NOWAIT);
+	if (!desc)
+		return NULL;
+
+	memset(desc, 0, sizeof(*desc));
+
+	dma_async_tx_descriptor_init(&desc->tx_desc, &chan->dma_chan);
+	desc->tx_desc.flags = flags;
+	desc->tx_desc.tx_submit = ccp_tx_submit;
+	desc->ccp = chan->ccp;
+	INIT_LIST_HEAD(&desc->pending);
+	INIT_LIST_HEAD(&desc->active);
+	desc->status = DMA_IN_PROGRESS;
+
+	return desc;
+}
+
+static struct ccp_dma_desc *ccp_create_desc(struct dma_chan *dma_chan,
+					    struct scatterlist *dst_sg,
+					    unsigned int dst_nents,
+					    struct scatterlist *src_sg,
+					    unsigned int src_nents,
+					    unsigned long flags)
+{
+	struct ccp_dma_chan *chan = container_of(dma_chan, struct ccp_dma_chan,
+						 dma_chan);
+	struct ccp_device *ccp = chan->ccp;
+	struct ccp_dma_desc *desc;
+	struct ccp_dma_cmd *cmd;
+	struct ccp_cmd *ccp_cmd;
+	struct ccp_passthru_nomap_engine *ccp_pt;
+	unsigned int src_offset, src_len;
+	unsigned int dst_offset, dst_len;
+	unsigned int len;
+	unsigned long sflags;
+	size_t total_len;
+
+	if (!dst_sg || !src_sg)
+		return NULL;
+
+	if (!dst_nents || !src_nents)
+		return NULL;
+
+	desc = ccp_alloc_dma_desc(chan, flags);
+	if (!desc)
+		return NULL;
+
+	total_len = 0;
+
+	src_len = sg_dma_len(src_sg);
+	src_offset = 0;
+
+	dst_len = sg_dma_len(dst_sg);
+	dst_offset = 0;
+
+	while (true) {
+		if (!src_len) {
+			src_nents--;
+			if (!src_nents)
+				break;
+
+			src_sg = sg_next(src_sg);
+			if (!src_sg)
+				break;
+
+			src_len = sg_dma_len(src_sg);
+			src_offset = 0;
+			continue;
+		}
+
+		if (!dst_len) {
+			dst_nents--;
+			if (!dst_nents)
+				break;
+
+			dst_sg = sg_next(dst_sg);
+			if (!dst_sg)
+				break;
+
+			dst_len = sg_dma_len(dst_sg);
+			dst_offset = 0;
+			continue;
+		}
+
+		len = min(dst_len, src_len);
+
+		cmd = ccp_alloc_dma_cmd(chan);
+		if (!cmd)
+			goto err;
+
+		ccp_cmd = &cmd->ccp_cmd;
+		ccp_pt = &ccp_cmd->u.passthru_nomap;
+		ccp_cmd->flags = CCP_CMD_MAY_BACKLOG;
+		ccp_cmd->flags |= CCP_CMD_PASSTHRU_NO_DMA_MAP;
+		ccp_cmd->engine = CCP_ENGINE_PASSTHRU;
+		ccp_pt->bit_mod = CCP_PASSTHRU_BITWISE_NOOP;
+		ccp_pt->byte_swap = CCP_PASSTHRU_BYTESWAP_NOOP;
+		ccp_pt->src_dma = sg_dma_address(src_sg) + src_offset;
+		ccp_pt->dst_dma = sg_dma_address(dst_sg) + dst_offset;
+		ccp_pt->src_len = len;
+		ccp_pt->final = 1;
+		ccp_cmd->callback = ccp_cmd_callback;
+		ccp_cmd->data = desc;
+
+		list_add_tail(&cmd->entry, &desc->pending);
+
+		dev_dbg(ccp->dev,
+			"%s - cmd=%p, src=%pad, dst=%pad, len=%llu\n", __func__,
+			cmd, &ccp_pt->src_dma,
+			&ccp_pt->dst_dma, ccp_pt->src_len);
+
+		total_len += len;
+
+		src_len -= len;
+		src_offset += len;
+
+		dst_len -= len;
+		dst_offset += len;
+	}
+
+	desc->len = total_len;
+
+	if (list_empty(&desc->pending))
+		goto err;
+
+	dev_dbg(ccp->dev, "%s - desc=%p\n", __func__, desc);
+
+	spin_lock_irqsave(&chan->lock, sflags);
+
+	list_add_tail(&desc->entry, &chan->pending);
+
+	spin_unlock_irqrestore(&chan->lock, sflags);
+
+	return desc;
+
+err:
+	ccp_free_cmd_resources(ccp, &desc->pending);
+	kmem_cache_free(ccp->dma_desc_cache, desc);
+
+	return NULL;
+}
+
+static struct dma_async_tx_descriptor *ccp_prep_dma_memcpy(
+	struct dma_chan *dma_chan, dma_addr_t dst, dma_addr_t src, size_t len,
+	unsigned long flags)
+{
+	struct ccp_dma_chan *chan = container_of(dma_chan, struct ccp_dma_chan,
+						 dma_chan);
+	struct ccp_dma_desc *desc;
+	struct scatterlist dst_sg, src_sg;
+
+	dev_dbg(chan->ccp->dev,
+		"%s - src=%pad, dst=%pad, len=%zu, flags=%#lx\n",
+		__func__, &src, &dst, len, flags);
+
+	sg_init_table(&dst_sg, 1);
+	sg_dma_address(&dst_sg) = dst;
+	sg_dma_len(&dst_sg) = len;
+
+	sg_init_table(&src_sg, 1);
+	sg_dma_address(&src_sg) = src;
+	sg_dma_len(&src_sg) = len;
+
+	desc = ccp_create_desc(dma_chan, &dst_sg, 1, &src_sg, 1, flags);
+	if (!desc)
+		return NULL;
+
+	return &desc->tx_desc;
+}
+
+static struct dma_async_tx_descriptor *ccp_prep_dma_sg(
+	struct dma_chan *dma_chan, struct scatterlist *dst_sg,
+	unsigned int dst_nents, struct scatterlist *src_sg,
+	unsigned int src_nents, unsigned long flags)
+{
+	struct ccp_dma_chan *chan = container_of(dma_chan, struct ccp_dma_chan,
+						 dma_chan);
+	struct ccp_dma_desc *desc;
+
+	dev_dbg(chan->ccp->dev,
+		"%s - src=%p, src_nents=%u dst=%p, dst_nents=%u, flags=%#lx\n",
+		__func__, src_sg, src_nents, dst_sg, dst_nents, flags);
+
+	desc = ccp_create_desc(dma_chan, dst_sg, dst_nents, src_sg, src_nents,
+			       flags);
+	if (!desc)
+		return NULL;
+
+	return &desc->tx_desc;
+}
+
+static struct dma_async_tx_descriptor *ccp_prep_dma_interrupt(
+	struct dma_chan *dma_chan, unsigned long flags)
+{
+	struct ccp_dma_chan *chan = container_of(dma_chan, struct ccp_dma_chan,
+						 dma_chan);
+	struct ccp_dma_desc *desc;
+
+	desc = ccp_alloc_dma_desc(chan, flags);
+	if (!desc)
+		return NULL;
+
+	return &desc->tx_desc;
+}
+
+static void ccp_issue_pending(struct dma_chan *dma_chan)
+{
+	struct ccp_dma_chan *chan = container_of(dma_chan, struct ccp_dma_chan,
+						 dma_chan);
+	struct ccp_dma_desc *desc;
+	unsigned long flags;
+
+	dev_dbg(chan->ccp->dev, "%s\n", __func__);
+
+	spin_lock_irqsave(&chan->lock, flags);
+
+	desc = __ccp_pending_to_active(chan);
+
+	spin_unlock_irqrestore(&chan->lock, flags);
+
+	/* If there was nothing active, start processing */
+	if (desc)
+		ccp_cmd_callback(desc, 0);
+}
+
+static enum dma_status ccp_tx_status(struct dma_chan *dma_chan,
+				     dma_cookie_t cookie,
+				     struct dma_tx_state *state)
+{
+	struct ccp_dma_chan *chan = container_of(dma_chan, struct ccp_dma_chan,
+						 dma_chan);
+	struct ccp_dma_desc *desc;
+	enum dma_status ret;
+	unsigned long flags;
+
+	if (chan->status == DMA_PAUSED) {
+		ret = DMA_PAUSED;
+		goto out;
+	}
+
+	ret = dma_cookie_status(dma_chan, cookie, state);
+	if (ret == DMA_COMPLETE) {
+		spin_lock_irqsave(&chan->lock, flags);
+
+		/* Get status from complete chain, if still there */
+		list_for_each_entry(desc, &chan->complete, entry) {
+			if (desc->tx_desc.cookie != cookie)
+				continue;
+
+			ret = desc->status;
+			break;
+		}
+
+		spin_unlock_irqrestore(&chan->lock, flags);
+	}
+
+out:
+	dev_dbg(chan->ccp->dev, "%s - %u\n", __func__, ret);
+
+	return ret;
+}
+
+static int ccp_pause(struct dma_chan *dma_chan)
+{
+	struct ccp_dma_chan *chan = container_of(dma_chan, struct ccp_dma_chan,
+						 dma_chan);
+
+	chan->status = DMA_PAUSED;
+
+	/*TODO: Wait for active DMA to complete before returning? */
+
+	return 0;
+}
+
+static int ccp_resume(struct dma_chan *dma_chan)
+{
+	struct ccp_dma_chan *chan = container_of(dma_chan, struct ccp_dma_chan,
+						 dma_chan);
+	struct ccp_dma_desc *desc;
+	unsigned long flags;
+
+	spin_lock_irqsave(&chan->lock, flags);
+
+	desc = list_first_entry_or_null(&chan->active, struct ccp_dma_desc,
+					entry);
+
+	spin_unlock_irqrestore(&chan->lock, flags);
+
+	/* Indicate the channel is running again */
+	chan->status = DMA_IN_PROGRESS;
+
+	/* If there was something active, re-start */
+	if (desc)
+		ccp_cmd_callback(desc, 0);
+
+	return 0;
+}
+
+static int ccp_terminate_all(struct dma_chan *dma_chan)
+{
+	struct ccp_dma_chan *chan = container_of(dma_chan, struct ccp_dma_chan,
+						 dma_chan);
+	unsigned long flags;
+
+	dev_dbg(chan->ccp->dev, "%s\n", __func__);
+
+	/*TODO: Wait for active DMA to complete before continuing */
+
+	spin_lock_irqsave(&chan->lock, flags);
+
+	/*TODO: Purge the complete list? */
+	ccp_free_desc_resources(chan->ccp, &chan->active);
+	ccp_free_desc_resources(chan->ccp, &chan->pending);
+
+	spin_unlock_irqrestore(&chan->lock, flags);
+
+	return 0;
+}
+
+int ccp_dmaengine_register(struct ccp_device *ccp)
+{
+	struct ccp_dma_chan *chan;
+	struct dma_device *dma_dev = &ccp->dma_dev;
+	struct dma_chan *dma_chan;
+	char *dma_cmd_cache_name;
+	char *dma_desc_cache_name;
+	unsigned int i;
+	int ret;
+
+	ccp->ccp_dma_chan = devm_kcalloc(ccp->dev, ccp->cmd_q_count,
+					 sizeof(*(ccp->ccp_dma_chan)),
+					 GFP_KERNEL);
+	if (!ccp->ccp_dma_chan)
+		return -ENOMEM;
+
+	dma_cmd_cache_name = devm_kasprintf(ccp->dev, GFP_KERNEL,
+					    "%s-dmaengine-cmd-cache",
+					    ccp->name);
+	if (!dma_cmd_cache_name)
+		return -ENOMEM;
+
+	ccp->dma_cmd_cache = kmem_cache_create(dma_cmd_cache_name,
+					       sizeof(struct ccp_dma_cmd),
+					       sizeof(void *),
+					       SLAB_HWCACHE_ALIGN, NULL);
+	if (!ccp->dma_cmd_cache)
+		return -ENOMEM;
+
+	dma_desc_cache_name = devm_kasprintf(ccp->dev, GFP_KERNEL,
+					     "%s-dmaengine-desc-cache",
+					     ccp->name);
+	if (!dma_cmd_cache_name)
+		return -ENOMEM;
+	ccp->dma_desc_cache = kmem_cache_create(dma_desc_cache_name,
+						sizeof(struct ccp_dma_desc),
+						sizeof(void *),
+						SLAB_HWCACHE_ALIGN, NULL);
+	if (!ccp->dma_desc_cache) {
+		ret = -ENOMEM;
+		goto err_cache;
+	}
+
+	dma_dev->dev = ccp->dev;
+	dma_dev->src_addr_widths = CCP_DMA_WIDTH(dma_get_mask(ccp->dev));
+	dma_dev->dst_addr_widths = CCP_DMA_WIDTH(dma_get_mask(ccp->dev));
+	dma_dev->directions = DMA_MEM_TO_MEM;
+	dma_dev->residue_granularity = DMA_RESIDUE_GRANULARITY_DESCRIPTOR;
+	dma_cap_set(DMA_MEMCPY, dma_dev->cap_mask);
+	dma_cap_set(DMA_SG, dma_dev->cap_mask);
+	dma_cap_set(DMA_INTERRUPT, dma_dev->cap_mask);
+
+	INIT_LIST_HEAD(&dma_dev->channels);
+	for (i = 0; i < ccp->cmd_q_count; i++) {
+		chan = ccp->ccp_dma_chan + i;
+		dma_chan = &chan->dma_chan;
+
+		chan->ccp = ccp;
+
+		spin_lock_init(&chan->lock);
+		INIT_LIST_HEAD(&chan->pending);
+		INIT_LIST_HEAD(&chan->active);
+		INIT_LIST_HEAD(&chan->complete);
+
+		tasklet_init(&chan->cleanup_tasklet, ccp_do_cleanup,
+			     (unsigned long)chan);
+
+		dma_chan->device = dma_dev;
+		dma_cookie_init(dma_chan);
+
+		list_add_tail(&dma_chan->device_node, &dma_dev->channels);
+	}
+
+	dma_dev->device_free_chan_resources = ccp_free_chan_resources;
+	dma_dev->device_prep_dma_memcpy = ccp_prep_dma_memcpy;
+	dma_dev->device_prep_dma_sg = ccp_prep_dma_sg;
+	dma_dev->device_prep_dma_interrupt = ccp_prep_dma_interrupt;
+	dma_dev->device_issue_pending = ccp_issue_pending;
+	dma_dev->device_tx_status = ccp_tx_status;
+	dma_dev->device_pause = ccp_pause;
+	dma_dev->device_resume = ccp_resume;
+	dma_dev->device_terminate_all = ccp_terminate_all;
+
+	ret = dma_async_device_register(dma_dev);
+	if (ret)
+		goto err_reg;
+
+	return 0;
+
+err_reg:
+	kmem_cache_destroy(ccp->dma_desc_cache);
+
+err_cache:
+	kmem_cache_destroy(ccp->dma_cmd_cache);
+
+	return ret;
+}
+
+void ccp_dmaengine_unregister(struct ccp_device *ccp)
+{
+	struct dma_device *dma_dev = &ccp->dma_dev;
+
+	dma_async_device_unregister(dma_dev);
+
+	kmem_cache_destroy(ccp->dma_desc_cache);
+	kmem_cache_destroy(ccp->dma_cmd_cache);
+}

drivers/crypto/ccp/ccp-ops.c

@@ -1427,6 +1427,70 @@ static int ccp_run_passthru_cmd(struct ccp_cmd_queue *cmd_q,
 	return ret;
 }
 
+static int ccp_run_passthru_nomap_cmd(struct ccp_cmd_queue *cmd_q,
+				      struct ccp_cmd *cmd)
+{
+	struct ccp_passthru_nomap_engine *pt = &cmd->u.passthru_nomap;
+	struct ccp_dm_workarea mask;
+	struct ccp_op op;
+	int ret;
+
+	if (!pt->final && (pt->src_len & (CCP_PASSTHRU_BLOCKSIZE - 1)))
+		return -EINVAL;
+
+	if (!pt->src_dma || !pt->dst_dma)
+		return -EINVAL;
+
+	if (pt->bit_mod != CCP_PASSTHRU_BITWISE_NOOP) {
+		if (pt->mask_len != CCP_PASSTHRU_MASKSIZE)
+			return -EINVAL;
+		if (!pt->mask)
+			return -EINVAL;
+	}
+
+	BUILD_BUG_ON(CCP_PASSTHRU_KSB_COUNT != 1);
+
+	memset(&op, 0, sizeof(op));
+	op.cmd_q = cmd_q;
+	op.jobid = ccp_gen_jobid(cmd_q->ccp);
+
+	if (pt->bit_mod != CCP_PASSTHRU_BITWISE_NOOP) {
+		/* Load the mask */
+		op.ksb_key = cmd_q->ksb_key;
+
+		mask.length = pt->mask_len;
+		mask.dma.address = pt->mask;
+		mask.dma.length = pt->mask_len;
+
+		ret = ccp_copy_to_ksb(cmd_q, &mask, op.jobid, op.ksb_key,
+				     CCP_PASSTHRU_BYTESWAP_NOOP);
+		if (ret) {
+			cmd->engine_error = cmd_q->cmd_error;
+			return ret;
+		}
+	}
+
+	/* Send data to the CCP Passthru engine */
+	op.eom = 1;
+	op.soc = 1;
+
+	op.src.type = CCP_MEMTYPE_SYSTEM;
+	op.src.u.dma.address = pt->src_dma;
+	op.src.u.dma.offset = 0;
+	op.src.u.dma.length = pt->src_len;
+
+	op.dst.type = CCP_MEMTYPE_SYSTEM;
+	op.dst.u.dma.address = pt->dst_dma;
+	op.dst.u.dma.offset = 0;
+	op.dst.u.dma.length = pt->src_len;
+
+	ret = cmd_q->ccp->vdata->perform->perform_passthru(&op);
+	if (ret)
+		cmd->engine_error = cmd_q->cmd_error;
+
+	return ret;
+}
+
 static int ccp_run_ecc_mm_cmd(struct ccp_cmd_queue *cmd_q, struct ccp_cmd *cmd)
 {
 	struct ccp_ecc_engine *ecc = &cmd->u.ecc;
@@ -1762,6 +1826,9 @@ int ccp_run_cmd(struct ccp_cmd_queue *cmd_q, struct ccp_cmd *cmd)
 		ret = ccp_run_rsa_cmd(cmd_q, cmd);
 		break;
 	case CCP_ENGINE_PASSTHRU:
+		if (cmd->flags & CCP_CMD_PASSTHRU_NO_DMA_MAP)
+			ret = ccp_run_passthru_nomap_cmd(cmd_q, cmd);
+		else
 			ret = ccp_run_passthru_cmd(cmd_q, cmd);
 		break;
 	case CCP_ENGINE_ECC:

include/linux/ccp.h

 /*
  * AMD Cryptographic Coprocessor (CCP) driver
  *
- * Copyright (C) 2013 Advanced Micro Devices, Inc.
+ * Copyright (C) 2013,2016 Advanced Micro Devices, Inc.
  *
  * Author: Tom Lendacky <thomas.lendacky@amd.com>
+ * Author: Gary R Hook <gary.hook@amd.com>
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 as
@@ -381,6 +382,35 @@ struct ccp_passthru_engine {
 	u32 final;
 };
 
+/**
+ * struct ccp_passthru_nomap_engine - CCP pass-through operation
+ *   without performing DMA mapping
+ * @bit_mod: bitwise operation to perform
+ * @byte_swap: byteswap operation to perform
+ * @mask: mask to be applied to data
+ * @mask_len: length in bytes of mask
+ * @src: data to be used for this operation
+ * @dst: data produced by this operation
+ * @src_len: length in bytes of data used for this operation
+ * @final: indicate final pass-through operation
+ *
+ * Variables required to be set when calling ccp_enqueue_cmd():
+ *   - bit_mod, byte_swap, src, dst, src_len
+ *   - mask, mask_len if bit_mod is not CCP_PASSTHRU_BITWISE_NOOP
+ */
+struct ccp_passthru_nomap_engine {
+	enum ccp_passthru_bitwise bit_mod;
+	enum ccp_passthru_byteswap byte_swap;
+
+	dma_addr_t mask;
+	u32 mask_len;		/* In bytes */
+
+	dma_addr_t src_dma, dst_dma;
+	u64 src_len;		/* In bytes */
+
+	u32 final;
+};
+
 /***** ECC engine *****/
 #define CCP_ECC_MODULUS_BYTES	48	/* 384-bits */
 #define CCP_ECC_MAX_OPERANDS	6
@@ -523,6 +553,7 @@ enum ccp_engine {
 
 /* Flag values for flags member of ccp_cmd */
 #define CCP_CMD_MAY_BACKLOG		0x00000001
+#define CCP_CMD_PASSTHRU_NO_DMA_MAP	0x00000002
 
 /**
  * struct ccp_cmd - CPP operation request
@@ -562,6 +593,7 @@ struct ccp_cmd {
 		struct ccp_sha_engine sha;
 		struct ccp_rsa_engine rsa;
 		struct ccp_passthru_engine passthru;
+		struct ccp_passthru_nomap_engine passthru_nomap;
 		struct ccp_ecc_engine ecc;
 	} u;