xref: /openbmc/u-boot/drivers/dma/dma-uclass.c (revision 90c08fa0)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Direct Memory Access U-Class driver
4  *
5  * (C) Copyright 2015
6  *     Texas Instruments Incorporated, <www.ti.com>
7  *
8  * Author: Mugunthan V N <mugunthanvnm@ti.com>
9  */
10 
11 #include <common.h>
12 #include <dma.h>
13 #include <dm.h>
14 #include <dm/uclass-internal.h>
15 #include <dm/device-internal.h>
16 #include <errno.h>
17 
18 int dma_get_device(u32 transfer_type, struct udevice **devp)
19 {
20 	struct udevice *dev;
21 	int ret;
22 
23 	for (ret = uclass_first_device(UCLASS_DMA, &dev); dev && !ret;
24 	     ret = uclass_next_device(&dev)) {
25 		struct dma_dev_priv *uc_priv;
26 
27 		uc_priv = dev_get_uclass_priv(dev);
28 		if (uc_priv->supported & transfer_type)
29 			break;
30 	}
31 
32 	if (!dev) {
33 		pr_err("No DMA device found that supports %x type\n",
34 		      transfer_type);
35 		return -EPROTONOSUPPORT;
36 	}
37 
38 	*devp = dev;
39 
40 	return ret;
41 }
42 
43 int dma_memcpy(void *dst, void *src, size_t len)
44 {
45 	struct udevice *dev;
46 	const struct dma_ops *ops;
47 	int ret;
48 
49 	ret = dma_get_device(DMA_SUPPORTS_MEM_TO_MEM, &dev);
50 	if (ret < 0)
51 		return ret;
52 
53 	ops = device_get_ops(dev);
54 	if (!ops->transfer)
55 		return -ENOSYS;
56 
57 	/* Invalidate the area, so no writeback into the RAM races with DMA */
58 	invalidate_dcache_range((unsigned long)dst, (unsigned long)dst +
59 				roundup(len, ARCH_DMA_MINALIGN));
60 
61 	return ops->transfer(dev, DMA_MEM_TO_MEM, dst, src, len);
62 }
63 
64 UCLASS_DRIVER(dma) = {
65 	.id		= UCLASS_DMA,
66 	.name		= "dma",
67 	.flags		= DM_UC_FLAG_SEQ_ALIAS,
68 	.per_device_auto_alloc_size = sizeof(struct dma_dev_priv),
69 };
70