[U-Boot] [RFC 01/14] dma: add dma channels support and improve uclass

Álvaro Fernández Rojas noltari at gmail.com
Mon Feb 12 16:38:45 UTC 2018


Signed-off-by: Álvaro Fernández Rojas <noltari at gmail.com>
---
 drivers/dma/dma-uclass.c    | 212 ++++++++++++++++++++++++++++++++++-------
 drivers/mtd/spi/sf-uclass.c |  17 ++++
 drivers/mtd/spi/spi_flash.c |  11 ++-
 include/dma-uclass.h        | 110 +++++++++++++++++++++
 include/dma.h               | 226 +++++++++++++++++++++++++++++++++-----------
 include/spi_flash.h         |   3 +
 6 files changed, 485 insertions(+), 94 deletions(-)
 create mode 100644 include/dma-uclass.h

diff --git a/drivers/dma/dma-uclass.c b/drivers/dma/dma-uclass.c
index 3d0ce22fbc..7d04d98493 100644
--- a/drivers/dma/dma-uclass.c
+++ b/drivers/dma/dma-uclass.c
@@ -1,59 +1,176 @@
 /*
- * Direct Memory Access U-Class driver
+ * Copyright (C) 2018 Álvaro Fernández Rojas <noltari at gmail.com>
+ * Copyright (C) 2015 Texas Instruments Incorporated, <www.ti.com>
+ * Written by Mugunthan V N <mugunthanvnm at ti.com>
  *
- * (C) Copyright 2015
- *     Texas Instruments Incorporated, <www.ti.com>
- *
- * Author: Mugunthan V N <mugunthanvnm at ti.com>
- *
- * SPDX-License-Identifier:     GPL-2.0+
+ * SPDX-License-Identifier:	GPL-2.0+
  */
 
 #include <common.h>
-#include <dma.h>
 #include <dm.h>
-#include <dm/uclass-internal.h>
-#include <dm/device-internal.h>
+#include <dma.h>
+#include <dma-uclass.h>
+#include <dt-structs.h>
 #include <errno.h>
 
 DECLARE_GLOBAL_DATA_PTR;
 
-int dma_get_device(u32 transfer_type, struct udevice **devp)
+static inline struct dma_ops *dma_dev_ops(struct udevice *dev)
+{
+	return (struct dma_ops *)dev->driver->ops;
+}
+
+#if CONFIG_IS_ENABLED(OF_CONTROL)
+# if CONFIG_IS_ENABLED(OF_PLATDATA)
+int dma_get_by_index_platdata(struct udevice *dev, int index,
+			      struct phandle_2_cell *cells, struct dma *dma)
 {
-	struct udevice *dev;
 	int ret;
 
-	for (ret = uclass_first_device(UCLASS_DMA, &dev); dev && !ret;
-	     ret = uclass_next_device(&dev)) {
-		struct dma_dev_priv *uc_priv;
+	if (index != 0)
+		return -ENOSYS;
+	ret = uclass_get_device(UCLASS_DMA, 0, &dma->dev);
+	if (ret)
+		return ret;
+	dma->id = cells[0].id;
 
-		uc_priv = dev_get_uclass_priv(dev);
-		if (uc_priv->supported & transfer_type)
-			break;
-	}
+	return 0;
+}
+# else
+static int dma_of_xlate_default(struct dma *dma,
+				struct fdtdec_phandle_args *args)
+{
+	debug("%s(dma=%p)\n", __func__, dma);
 
-	if (!dev) {
-		pr_err("No DMA device found that supports %x type\n",
-		      transfer_type);
-		return -EPROTONOSUPPORT;
+	if (args->args_count > 1) {
+		pr_err("Invaild args_count: %d\n", args->args_count);
+		return -EINVAL;
 	}
 
-	*devp = dev;
+	if (args->args_count)
+		dma->id = args->args[0];
+	else
+		dma->id = 0;
 
-	return ret;
+	return 0;
 }
 
-int dma_memcpy(void *dst, void *src, size_t len)
+int dma_get_by_index(struct udevice *dev, int index, struct dma *dma)
 {
-	struct udevice *dev;
-	const struct dma_ops *ops;
 	int ret;
+	struct fdtdec_phandle_args args;
+	struct udevice *dev_dma;
+	struct dma_ops *ops;
+
+	debug("%s(dev=%p, index=%d, dma=%p)\n", __func__, dev, index, dma);
 
-	ret = dma_get_device(DMA_SUPPORTS_MEM_TO_MEM, &dev);
-	if (ret < 0)
+	assert(dma);
+	ret = fdtdec_parse_phandle_with_args(gd->fdt_blob, dev_of_offset(dev),
+					     "dmas", "#dma-cells", 0, index,
+					     &args);
+	if (ret) {
+		pr_err("%s: fdtdec_parse_phandle_with_args failed: err=%d\n",
+		      __func__, ret);
 		return ret;
+	}
+
+	ret = uclass_get_device_by_of_offset(UCLASS_DMA, args.node, &dev_dma);
+	if (ret) {
+		pr_err("%s: uclass_get_device_by_of_offset failed: err=%d\n",
+		      __func__, ret);
+		return ret;
+	}
+
+	dma->dev = dev_dma;
+
+	ops = dma_dev_ops(dev_dma);
+
+	if (ops->of_xlate)
+		ret = ops->of_xlate(dma, &args);
+	else
+		ret = dma_of_xlate_default(dma, &args);
+	if (ret) {
+		pr_err("of_xlate() failed: %d\n", ret);
+		return ret;
+	}
+
+	return dma_request(dev_dma, dma);
+}
+# endif /* OF_PLATDATA */
+
+int dma_get_by_name(struct udevice *dev, const char *name, struct dma *dma)
+{
+	int index;
+
+	debug("%s(dev=%p, name=%s, dma=%p)\n", __func__, dev, name, dma);
+
+	index = fdt_stringlist_search(gd->fdt_blob, dev_of_offset(dev),
+				      "dma-names", name);
+	if (index < 0) {
+		pr_err("fdt_stringlist_search() failed: %d\n", index);
+		return index;
+	}
+
+	return dma_get_by_index(dev, index, dma);
+}
+#endif /* OF_CONTROL */
+
+int dma_request(struct udevice *dev, struct dma *dma)
+{
+	struct dma_ops *ops = dma_dev_ops(dev);
+
+	debug("%s(dev=%p, dma=%p)\n", __func__, dev, dma);
+
+	dma->dev = dev;
+
+	if (!ops->request)
+		return 0;
+
+	return ops->request(dma);
+}
+
+int dma_free(struct dma *dma)
+{
+	struct dma_ops *ops = dma_dev_ops(dma->dev);
+
+	debug("%s(dma=%p)\n", __func__, dma);
+
+	if (!ops->free)
+		return 0;
+
+	return ops->free(dma);
+}
+
+int dma_enable(struct dma *dma)
+{
+	struct dma_ops *ops = dma_dev_ops(dma->dev);
+
+	debug("%s(dma=%p)\n", __func__, dma);
+
+	if (!ops->enable)
+		return -ENOSYS;
+
+	return ops->enable(dma);
+}
+
+int dma_disable(struct dma *dma)
+{
+	struct dma_ops *ops = dma_dev_ops(dma->dev);
+
+	debug("%s(dma=%p)\n", __func__, dma);
+
+	if (!ops->disable)
+		return -ENOSYS;
+
+	return ops->disable(dma);
+}
+
+int dma_memcpy(struct dma *dma, void *dst, void *src, size_t len)
+{
+	struct dma_ops *ops = dma_dev_ops(dma->dev);
+
+	debug("%s(dma=%p)\n", __func__, dma);
 
-	ops = device_get_ops(dev);
 	if (!ops->transfer)
 		return -ENOSYS;
 
@@ -61,12 +178,35 @@ int dma_memcpy(void *dst, void *src, size_t len)
 	invalidate_dcache_range((unsigned long)dst, (unsigned long)dst +
 				roundup(len, ARCH_DMA_MINALIGN));
 
-	return ops->transfer(dev, DMA_MEM_TO_MEM, dst, src, len);
+	return ops->transfer(dma, DMA_MEM_TO_MEM, dst, src, len);
+}
+
+int dma_receive(struct dma *dma, void **dst)
+{
+	struct dma_ops *ops = dma_dev_ops(dma->dev);
+
+	debug("%s(dma=%p)\n", __func__, dma);
+
+	if (!ops->receive)
+		return -1;
+
+	return ops->receive(dma, dst);
+}
+
+int dma_send(struct dma *dma, void *src, size_t len)
+{
+	struct dma_ops *ops = dma_dev_ops(dma->dev);
+
+	debug("%s(dma=%p)\n", __func__, dma);
+
+	if (!ops->send)
+		return -1;
+
+	return ops->send(dma, src, len);
 }
 
 UCLASS_DRIVER(dma) = {
-	.id		= UCLASS_DMA,
-	.name		= "dma",
-	.flags		= DM_UC_FLAG_SEQ_ALIAS,
-	.per_device_auto_alloc_size = sizeof(struct dma_dev_priv),
+	.id = UCLASS_DMA,
+	.name = "dma",
+	.flags = DM_UC_FLAG_SEQ_ALIAS,
 };
diff --git a/drivers/mtd/spi/sf-uclass.c b/drivers/mtd/spi/sf-uclass.c
index 83876485fe..992dead1a2 100644
--- a/drivers/mtd/spi/sf-uclass.c
+++ b/drivers/mtd/spi/sf-uclass.c
@@ -6,6 +6,7 @@
 
 #include <common.h>
 #include <dm.h>
+#include <dma.h>
 #include <spi.h>
 #include <spi_flash.h>
 #include <dm/device-internal.h>
@@ -72,6 +73,22 @@ int spi_flash_probe_bus_cs(unsigned int busnum, unsigned int cs,
 		return ret;
 
 	*devp = slave->dev;
+
+#ifdef CONFIG_DMA
+	if (fdtdec_lookup_phandle(gd->fdt_blob, dev_of_offset(*devp),
+				  "dmas") > 0) {
+		struct spi_flash *priv = dev_get_uclass_priv(*devp);
+
+		priv->dma = calloc(1, sizeof(struct dma));
+		if (!priv->dma)
+			return -ENOMEM;
+
+		ret = dma_get_by_index(*devp, 0, priv->dma);
+		if (ret)
+			return -EINVAL;
+	}
+#endif
+
 	return 0;
 }
 
diff --git a/drivers/mtd/spi/spi_flash.c b/drivers/mtd/spi/spi_flash.c
index 294d9f9d79..8b1c6a27de 100644
--- a/drivers/mtd/spi/spi_flash.c
+++ b/drivers/mtd/spi/spi_flash.c
@@ -458,10 +458,6 @@ int spi_flash_read_common(struct spi_flash *flash, const u8 *cmd,
  */
 void __weak spi_flash_copy_mmap(void *data, void *offset, size_t len)
 {
-#ifdef CONFIG_DMA
-	if (!dma_memcpy(data, offset, len))
-		return;
-#endif
 	memcpy(data, offset, len);
 }
 
@@ -482,7 +478,12 @@ int spi_flash_cmd_read_ops(struct spi_flash *flash, u32 offset,
 			return ret;
 		}
 		spi_xfer(spi, 0, NULL, NULL, SPI_XFER_MMAP);
-		spi_flash_copy_mmap(data, flash->memory_map + offset, len);
+		if (flash->dma)
+			dma_memcpy(flash->dma, data,
+				   flash->memory_map + offset, len);
+		else
+			spi_flash_copy_mmap(data, flash->memory_map + offset,
+					    len);
 		spi_xfer(spi, 0, NULL, NULL, SPI_XFER_MMAP_END);
 		spi_release_bus(spi);
 		return 0;
diff --git a/include/dma-uclass.h b/include/dma-uclass.h
new file mode 100644
index 0000000000..0315e54441
--- /dev/null
+++ b/include/dma-uclass.h
@@ -0,0 +1,110 @@
+/*
+ * Copyright (C) 2018 Álvaro Fernández Rojas <noltari at gmail.com>
+ * Copyright (C) 2015 Texas Instruments Incorporated, <www.ti.com>
+ * Written by Mugunthan V N <mugunthanvnm at ti.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#ifndef _DMA_UCLASS_H
+#define _DMA_UCLASS_H
+
+/* See dma.h for background documentation. */
+
+#include <dma.h>
+#include <fdtdec.h>
+
+/**
+ * struct dma_ops - The functions that a DMA driver must implement.
+ */
+struct dma_ops {
+	/**
+	 * of_xlate - Translate a client's device-tree (OF) DMA specifier.
+	 *
+	 * The DMA core calls this function as the first step in implementing
+	 * a client's dma_get_by_*() call.
+	 *
+	 * If this function pointer is set to NULL, the DMA core will use a
+	 * default implementation, which assumes #dma-cells = <1>, and that
+	 * the DT cell contains a simple integer DMA Channel.
+	 *
+	 * At present, the DMA API solely supports device-tree. If this
+	 * changes, other xxx_xlate() functions may be added to support those
+	 * other mechanisms.
+	 *
+	 * @dma: The dma struct to hold the translation result.
+	 * @args:	The dma specifier values from device tree.
+	 * @return 0 if OK, or a negative error code.
+	 */
+	int (*of_xlate)(struct dma *dma,
+			struct fdtdec_phandle_args *args);
+	/**
+	 * request - Request a translated DMA.
+	 *
+	 * The DMA core calls this function as the second step in
+	 * implementing a client's dma_get_by_*() call, following a successful
+	 * xxx_xlate() call, or as the only step in implementing a client's
+	 * dma_request() call.
+	 *
+	 * @dma: The DMA struct to request; this has been filled in by
+	 *   a previoux xxx_xlate() function call, or by the caller of
+	 *   dma_request().
+	 * @return 0 if OK, or a negative error code.
+	 */
+	int (*request)(struct dma *dma);
+	/**
+	 * free - Free a previously requested dma.
+	 *
+	 * This is the implementation of the client dma_free() API.
+	 *
+	 * @dma: The DMA to free.
+	 * @return 0 if OK, or a negative error code.
+	 */
+	int (*free)(struct dma *dma);
+	/**
+	 * enable() - Enable a DMA Channel.
+	 *
+	 * @dma: The DMA Channel to manipulate.
+	 * @return zero on success, or -ve error code.
+	 */
+	int (*enable)(struct dma *dma);
+	/**
+	 * disable() - Disable a DMA Channel.
+	 *
+	 * @dma: The DMA Channel to manipulate.
+	 * @return zero on success, or -ve error code.
+	 */
+	int (*disable)(struct dma *dma);
+	/**
+	 * transfer() - Issue a DMA transfer.
+	 *
+	 * @dma: The DMA Channel to manipulate.
+	 * @dir: The direction of data transfer.
+	 * @dst: The destination pointer.
+	 * @src: The source pointer.
+	 * @len: Length of the data to be copied.
+	 * @return zero on success, or -ve error code.
+	 */
+	int (*transfer)(struct dma *dma, enum dma_transfer_direction dir,
+			void *dst, void *src, size_t len);
+	/**
+	 * receive() - Receive a DMA transfer.
+	 *
+	 * @dma: The DMA Channel to manipulate.
+	 * @dst: The destination pointer.
+	 * @return zero on success, or -ve error code.
+	 */
+	int (*receive)(struct dma *dma, void **dst);
+	/**
+	 * send() - Send a DMA transfer.
+	 *
+	 * @dma: The DMA Channel to manipulate.
+	 * @src: The source pointer.
+	 * @len: Length of the data to be copied.
+	 * @return zero on success, or -ve error code.
+	 */
+	int (*send)(struct dma *dma, void *src, size_t len);
+
+};
+
+#endif /* _DMA_UCLASS_H */
diff --git a/include/dma.h b/include/dma.h
index 71fa77f2ea..3632e3256d 100644
--- a/include/dma.h
+++ b/include/dma.h
@@ -1,86 +1,206 @@
 /*
- * (C) Copyright 2015
- *     Texas Instruments Incorporated, <www.ti.com>
+ * Copyright (C) 2018 Álvaro Fernández Rojas <noltari at gmail.com>
+ * Copyright (C) 2015 Texas Instruments Incorporated, <www.ti.com>
+ * Written by Mugunthan V N <mugunthanvnm at ti.com>
  *
- * SPDX-License-Identifier:     GPL-2.0+
+ * SPDX-License-Identifier:	GPL-2.0+
  */
 
 #ifndef _DMA_H_
 #define _DMA_H_
 
+#include <linux/errno.h>
+#include <linux/types.h>
+
 /*
- * enum dma_direction - dma transfer direction indicator
+ * enum dma_transfer_direction - dma transfer direction indicator
  * @DMA_MEM_TO_MEM: Memcpy mode
  * @DMA_MEM_TO_DEV: From Memory to Device
  * @DMA_DEV_TO_MEM: From Device to Memory
  * @DMA_DEV_TO_DEV: From Device to Device
  */
-enum dma_direction {
+enum dma_transfer_direction {
 	DMA_MEM_TO_MEM,
 	DMA_MEM_TO_DEV,
 	DMA_DEV_TO_MEM,
 	DMA_DEV_TO_DEV,
 };
 
-#define DMA_SUPPORTS_MEM_TO_MEM	BIT(0)
-#define DMA_SUPPORTS_MEM_TO_DEV	BIT(1)
-#define DMA_SUPPORTS_DEV_TO_MEM	BIT(2)
-#define DMA_SUPPORTS_DEV_TO_DEV	BIT(3)
+/**
+ * A DMA is a feature of computer systems that allows certain hardware 
+ * subsystems to access main system memory, independent of the CPU.
+ * DMA channels are typically generated externally to the HW module
+ * consuming them, by an entity this API calls a DMA provider. This API
+ * provides a standard means for drivers to enable and disable DMAs, and to
+ * copy, send and receive data using DMA.
+ * 
+ * A driver that implements UCLASS_DMA is a DMA provider. A provider will
+ * often implement multiple separate DMAs, since the hardware it manages
+ * often has this capability. dma_uclass.h describes the interface which
+ * DMA providers must implement.
+ * 
+ * DMA consumers/clients are the HW modules driven by the DMA channels. This
+ * header file describes the API used by drivers for those HW modules.
+ */
 
-/*
- * struct dma_ops - Driver model DMA operations
+struct udevice;
+
+/**
+ * struct dma - A handle to (allowing control of) a single DMA.
+ *
+ * Clients provide storage for DMA handles. The content of the structure is
+ * managed solely by the DMA API and DMA drivers. A DMA struct is
+ * initialized by "get"ing the DMA struct. The DMA struct is passed to all
+ * other DMA APIs to identify which DMA channel to operate upon.
  *
- * The uclass interface is implemented by all DMA devices which use
- * driver model.
+ * @dev: The device which implements the DMA channel.
+ * @id: The DMA channel ID within the provider.
+ *
+ * Currently, the DMA API assumes that a single integer ID is enough to
+ * identify and configure any DMA channel for any DMA provider. If this
+ * assumption becomes invalid in the future, the struct could be expanded to
+ * either (a) add more fields to allow DMA providers to store additional
+ * information, or (b) replace the id field with an opaque pointer, which the
+ * provider would dynamically allocated during its .of_xlate op, and process
+ * during is .request op. This may require the addition of an extra op to clean
+ * up the allocation.
  */
-struct dma_ops {
+struct dma {
+	struct udevice *dev;
 	/*
-	 * Get the current timer count
-	 *
-	 * @dev: The DMA device
-	 * @direction: direction of data transfer should be one from
-		       enum dma_direction
-	 * @dst: Destination pointer
-	 * @src: Source pointer
-	 * @len: Length of the data to be copied.
-	 * @return: 0 if OK, -ve on error
+	 * Written by of_xlate. We assume a single id is enough for now. In the
+	 * future, we might add more fields here.
 	 */
-	int (*transfer)(struct udevice *dev, int direction, void *dst,
-			void *src, size_t len);
+	unsigned long id;
 };
 
-/*
- * struct dma_dev_priv - information about a device used by the uclass
+#if CONFIG_IS_ENABLED(OF_CONTROL) && CONFIG_IS_ENABLED(DMA)
+struct phandle_2_cell;
+int dma_get_by_index_platdata(struct udevice *dev, int index,
+			      struct phandle_2_cell *cells, struct dma *dma);
+
+/**
+ * dma_get_by_index - Get/request a DMA by integer index.
+ *
+ * This looks up and requests a DMA. The index is relative to the client
+ * device; each device is assumed to have n DMAs associated with it somehow,
+ * and this function finds and requests one of them. The mapping of client
+ * device DMA indices to provider DMAs may be via device-tree properties,
+ * board-provided mapping tables, or some other mechanism.
  *
- * @supported: mode of transfers that DMA can support, should be
- *	       one/multiple of DMA_SUPPORTS_*
+ * @dev:	The client device.
+ * @index:	The index of the DMA to request, within the client's list of
+ *		DMA channels.
+ * @dma:	A pointer to a DMA struct to initialize.
+ * @return 0 if OK, or a negative error code.
  */
-struct dma_dev_priv {
-	u32 supported;
-};
+int dma_get_by_index(struct udevice *dev, int index, struct dma *dma);
 
-/*
- * dma_get_device - get a DMA device which supports transfer
- * type of transfer_type
- *
- * @transfer_type - transfer type should be one/multiple of
- *		    DMA_SUPPORTS_*
- * @devp - udevice pointer to return the found device
- * @return - will return on success and devp will hold the
- *	     pointer to the device
+/**
+ * dma_get_by_name - Get/request a DMA by name.
+ *
+ * This looks up and requests a DMA. The name is relative to the client
+ * device; each device is assumed to have n DMAs associated with it somehow,
+ * and this function finds and requests one of them. The mapping of client
+ * device DMA names to provider DMAs may be via device-tree properties,
+ * board-provided mapping tables, or some other mechanism.
+ *
+ * @dev:	The client device.
+ * @name:	The name of the DMA to request, within the client's list of
+ *		DMA channels.
+ * @dma:	A pointer to a DMA struct to initialize.
+ * @return 0 if OK, or a negative error code.
  */
-int dma_get_device(u32 transfer_type, struct udevice **devp);
+int dma_get_by_name(struct udevice *dev, const char *name, struct dma *dma);
+#else
+static inline int dma_get_by_index(struct udevice *dev, int index,
+				   struct dma *dma)
+{
+	return -ENOSYS;
+}
 
-/*
- * dma_memcpy - try to use DMA to do a mem copy which will be
- *		much faster than CPU mem copy
- *
- * @dst - destination pointer
- * @src - souce pointer
- * @len - data length to be copied
- * @return - on successful transfer returns no of bytes
-	     transferred and on failure return error code.
+static inline int dma_get_by_name(struct udevice *dev, const char *name,
+			   struct dma *dma)
+{
+	return -ENOSYS;
+}
+#endif
+
+/**
+ * dma_request - Request a DMA by provider-specific ID.
+ *
+ * This requests a DMA using a provider-specific ID. Generally, this function
+ * should not be used, since dma_get_by_index/name() provide an interface that
+ * better separates clients from intimate knowledge of DMA providers.
+ * However, this function may be useful in core SoC-specific code.
+ *
+ * @dev: The DMA provider device.
+ * @dma: A pointer to a DMA struct to initialize. The caller must
+ *	 have already initialized any field in this struct which the
+ *	 DMA provider uses to identify the DMA channel.
+ * @return 0 if OK, or a negative error code.
+ */
+int dma_request(struct udevice *dev, struct dma *dma);
+
+/**
+ * dma_free - Free a previously requested DMA.
+ *
+ * @dma: A DMA struct that was previously successfully requested by
+ *	 dma_request/get_by_*().
+ * @return 0 if OK, or a negative error code.
+ */
+int dma_free(struct dma *dma);
+
+/**
+ * dma_enable() - Enable (turn on) a DMA channel.
+ *
+ * @dma: A DMA struct that was previously successfully requested by
+ *	 dma_request/get_by_*().
+ * @return zero on success, or -ve error code.
+ */
+int dma_enable(struct dma *dma);
+
+/**
+ * dma_disable() - Disable (turn off) a DMA channel.
+ *
+ * @dma: A DMA struct that was previously successfully requested by
+ *	 dma_request/get_by_*().
+ * @return zero on success, or -ve error code.
+ */
+int dma_disable(struct dma *dma);
+
+/**
+ * dma_memcpy() - Try to use DMA to do a mem copy which will be much faster
+ *		  than CPU mem copy.
+ *
+ * @dma: A DMA struct that was previously successfully requested by
+ *	 dma_request/get_by_*().
+ * @dst: The destination pointer.
+ * @src: The source pointer.
+ * @len: Length of the data to be copied.
+ * @return zero on success, or -ve error code.
+ */
+int dma_memcpy(struct dma *dma, void *dst, void *src, size_t len);
+
+/**
+ * dma_receive() - Receive a DMA transfer.
+ *
+ * @dma: A DMA struct that was previously successfully requested by
+ *	 dma_request/get_by_*().
+ * @dst: The destination pointer.
+ * @return zero on success, or -ve error code.
+ */
+int dma_receive(struct dma *dma, void **dst);
+
+/**
+ * dma_send() - Send a DMA transfer.
+ *
+ * @dma: A DMA struct that was previously successfully requested by
+ *	 dma_request/get_by_*().
+ * @src: The source pointer.
+ * @len: Length of the data to be copied.
+ * @return zero on success, or -ve error code.
  */
-int dma_memcpy(void *dst, void *src, size_t len);
+int dma_send(struct dma *dma, void *src, size_t len);
 
-#endif	/* _DMA_H_ */
+#endif /* _DMA_H_ */
diff --git a/include/spi_flash.h b/include/spi_flash.h
index f3c4e83424..f31e8b8145 100644
--- a/include/spi_flash.h
+++ b/include/spi_flash.h
@@ -65,6 +65,9 @@ struct spi_flash {
 #ifdef CONFIG_DM_SPI_FLASH
 	struct udevice *dev;
 #endif
+#ifdef CONFIG_DMA
+	struct dma *dma;
+#endif
 	const char *name;
 	u8 dual_flash;
 	u8 shift;
-- 
2.11.0



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