xref: /OK3568_Linux_fs/u-boot/drivers/ram/ramdisk_ro.c (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun // SPDX-License-Identifier:     GPL-2.0+
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun  * (C) Copyright 2018 Rockchip Electronics Co., Ltd
4*4882a593Smuzhiyun  */
5*4882a593Smuzhiyun 
6*4882a593Smuzhiyun #include <common.h>
7*4882a593Smuzhiyun #include <dm.h>
8*4882a593Smuzhiyun #include <dm/device-internal.h>
9*4882a593Smuzhiyun #include <dm/lists.h>
10*4882a593Smuzhiyun #include <dm/root.h>
11*4882a593Smuzhiyun #include <ramdisk.h>
12*4882a593Smuzhiyun 
13*4882a593Smuzhiyun DECLARE_GLOBAL_DATA_PTR;
14*4882a593Smuzhiyun 
ramdisk_ro_bread(struct blk_desc * desc,lbaint_t start,lbaint_t blkcnt,void * dst)15*4882a593Smuzhiyun static ulong ramdisk_ro_bread(struct blk_desc *desc, lbaint_t start,
16*4882a593Smuzhiyun 			      lbaint_t blkcnt, void *dst)
17*4882a593Smuzhiyun {
18*4882a593Smuzhiyun 	unsigned long b_size, b_start;
19*4882a593Smuzhiyun 
20*4882a593Smuzhiyun 	/* Byte */
21*4882a593Smuzhiyun 	b_start = start * desc->blksz;
22*4882a593Smuzhiyun 	b_size = blkcnt * desc->blksz;
23*4882a593Smuzhiyun 
24*4882a593Smuzhiyun 	if ((ulong)dst != (ulong)b_start)
25*4882a593Smuzhiyun 		memcpy((char *)dst, (char *)b_start, b_size);
26*4882a593Smuzhiyun 	else
27*4882a593Smuzhiyun 		debug("%s: skip memcpy at: 0x%08lx\n", __func__, (ulong)b_start);
28*4882a593Smuzhiyun 
29*4882a593Smuzhiyun 	debug("%s: b_start=0x%lx, b_size=0x%lx. dst=%p\n",
30*4882a593Smuzhiyun 	      __func__, b_start, b_size, dst);
31*4882a593Smuzhiyun 
32*4882a593Smuzhiyun 	return blkcnt;
33*4882a593Smuzhiyun }
34*4882a593Smuzhiyun 
ramdisk_ro_bind(struct udevice * dev)35*4882a593Smuzhiyun static int ramdisk_ro_bind(struct udevice *dev)
36*4882a593Smuzhiyun {
37*4882a593Smuzhiyun 	struct udevice *bdev;
38*4882a593Smuzhiyun 	int ret;
39*4882a593Smuzhiyun 
40*4882a593Smuzhiyun 	ret = blk_create_devicef(dev, "ramdisk_blk", "blk",
41*4882a593Smuzhiyun 				 IF_TYPE_RAMDISK, 0, 512, 0, &bdev);
42*4882a593Smuzhiyun 	if (ret) {
43*4882a593Smuzhiyun 		debug("Can't create block device\n");
44*4882a593Smuzhiyun 		return ret;
45*4882a593Smuzhiyun 	}
46*4882a593Smuzhiyun 
47*4882a593Smuzhiyun 	return 0;
48*4882a593Smuzhiyun }
49*4882a593Smuzhiyun 
50*4882a593Smuzhiyun static const struct ramdisk_ops ramdisk_ro_ops = {
51*4882a593Smuzhiyun 	.read = ramdisk_ro_bread,
52*4882a593Smuzhiyun };
53*4882a593Smuzhiyun 
54*4882a593Smuzhiyun static const struct udevice_id ramdisk_ro_ids[] = {
55*4882a593Smuzhiyun 	{ .compatible = "ramdisk-ro" },
56*4882a593Smuzhiyun 	{ }
57*4882a593Smuzhiyun };
58*4882a593Smuzhiyun 
59*4882a593Smuzhiyun U_BOOT_DRIVER(ramdisk_ro) = {
60*4882a593Smuzhiyun 	.name		= "ramdisk-ro",
61*4882a593Smuzhiyun 	.id		= UCLASS_RAMDISK,
62*4882a593Smuzhiyun 	.ops		= &ramdisk_ro_ops,
63*4882a593Smuzhiyun 	.of_match	= ramdisk_ro_ids,
64*4882a593Smuzhiyun 	.bind		= ramdisk_ro_bind,
65*4882a593Smuzhiyun };
66*4882a593Smuzhiyun 
67*4882a593Smuzhiyun U_BOOT_DEVICE(ramdisk_ro) = {
68*4882a593Smuzhiyun 	.name		= "ramdisk-ro",
69*4882a593Smuzhiyun };
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