xref: /openbmc/u-boot/drivers/dma/dma-uclass.c (revision 52dd704b)
1 /*
2  * Direct Memory Access U-Class driver
3  *
4  * (C) Copyright 2015
5  *     Texas Instruments Incorporated, <www.ti.com>
6  *
7  * Author: Mugunthan V N <mugunthanvnm@ti.com>
8  *
9  * SPDX-License-Identifier:     GPL-2.0+
10  */
11 
12 #include <common.h>
13 #include <dma.h>
14 #include <dm.h>
15 #include <dm/uclass-internal.h>
16 #include <dm/device-internal.h>
17 #include <errno.h>
18 
19 DECLARE_GLOBAL_DATA_PTR;
20 
21 int dma_get_device(u32 transfer_type, struct udevice **devp)
22 {
23 	struct udevice *dev;
24 	int ret;
25 
26 	for (ret = uclass_first_device(UCLASS_DMA, &dev); dev && !ret;
27 	     ret = uclass_next_device(&dev)) {
28 		struct dma_dev_priv *uc_priv;
29 
30 		uc_priv = dev_get_uclass_priv(dev);
31 		if (uc_priv->supported & transfer_type)
32 			break;
33 	}
34 
35 	if (!dev) {
36 		error("No DMA device found that supports %x type\n",
37 		      transfer_type);
38 		return -EPROTONOSUPPORT;
39 	}
40 
41 	*devp = dev;
42 
43 	return ret;
44 }
45 
46 int dma_memcpy(void *dst, void *src, size_t len)
47 {
48 	struct udevice *dev;
49 	const struct dma_ops *ops;
50 	int ret;
51 
52 	ret = dma_get_device(DMA_SUPPORTS_MEM_TO_MEM, &dev);
53 	if (ret < 0)
54 		return ret;
55 
56 	ops = device_get_ops(dev);
57 	if (!ops->transfer)
58 		return -ENOSYS;
59 
60 	/* Invalidate the area, so no writeback into the RAM races with DMA */
61 	invalidate_dcache_range((unsigned long)dst, (unsigned long)dst +
62 				roundup(len, ARCH_DMA_MINALIGN));
63 
64 	return ops->transfer(dev, DMA_MEM_TO_MEM, dst, src, len);
65 }
66 
67 UCLASS_DRIVER(dma) = {
68 	.id		= UCLASS_DMA,
69 	.name		= "dma",
70 	.flags		= DM_UC_FLAG_SEQ_ALIAS,
71 	.per_device_auto_alloc_size = sizeof(struct dma_dev_priv),
72 };
73