xref: /OK3568_Linux_fs/u-boot/drivers/ram/ramdisk_ro.c (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1 // SPDX-License-Identifier:     GPL-2.0+
2 /*
3  * (C) Copyright 2018 Rockchip Electronics Co., Ltd
4  */
5 
6 #include <common.h>
7 #include <dm.h>
8 #include <dm/device-internal.h>
9 #include <dm/lists.h>
10 #include <dm/root.h>
11 #include <ramdisk.h>
12 
13 DECLARE_GLOBAL_DATA_PTR;
14 
ramdisk_ro_bread(struct blk_desc * desc,lbaint_t start,lbaint_t blkcnt,void * dst)15 static ulong ramdisk_ro_bread(struct blk_desc *desc, lbaint_t start,
16 			      lbaint_t blkcnt, void *dst)
17 {
18 	unsigned long b_size, b_start;
19 
20 	/* Byte */
21 	b_start = start * desc->blksz;
22 	b_size = blkcnt * desc->blksz;
23 
24 	if ((ulong)dst != (ulong)b_start)
25 		memcpy((char *)dst, (char *)b_start, b_size);
26 	else
27 		debug("%s: skip memcpy at: 0x%08lx\n", __func__, (ulong)b_start);
28 
29 	debug("%s: b_start=0x%lx, b_size=0x%lx. dst=%p\n",
30 	      __func__, b_start, b_size, dst);
31 
32 	return blkcnt;
33 }
34 
ramdisk_ro_bind(struct udevice * dev)35 static int ramdisk_ro_bind(struct udevice *dev)
36 {
37 	struct udevice *bdev;
38 	int ret;
39 
40 	ret = blk_create_devicef(dev, "ramdisk_blk", "blk",
41 				 IF_TYPE_RAMDISK, 0, 512, 0, &bdev);
42 	if (ret) {
43 		debug("Can't create block device\n");
44 		return ret;
45 	}
46 
47 	return 0;
48 }
49 
50 static const struct ramdisk_ops ramdisk_ro_ops = {
51 	.read = ramdisk_ro_bread,
52 };
53 
54 static const struct udevice_id ramdisk_ro_ids[] = {
55 	{ .compatible = "ramdisk-ro" },
56 	{ }
57 };
58 
59 U_BOOT_DRIVER(ramdisk_ro) = {
60 	.name		= "ramdisk-ro",
61 	.id		= UCLASS_RAMDISK,
62 	.ops		= &ramdisk_ro_ops,
63 	.of_match	= ramdisk_ro_ids,
64 	.bind		= ramdisk_ro_bind,
65 };
66 
67 U_BOOT_DEVICE(ramdisk_ro) = {
68 	.name		= "ramdisk-ro",
69 };
70