xref: /rk3399_rockchip-uboot/drivers/ram/ramdisk_ro.c (revision 331c2375688d79920fb06b8f0c4c52a7df56fb29)
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 
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 	memcpy((char *)dst, (char *)b_start, b_size);
24 
25 	debug("%s: b_start=0x%lx, b_size=0x%lx. dst=%p\n",
26 	      __func__, b_start, b_size, dst);
27 
28 	return blkcnt;
29 }
30 
31 static int ramdisk_ro_bind(struct udevice *dev)
32 {
33 	struct udevice *bdev;
34 	int ret;
35 
36 	ret = blk_create_devicef(dev, "ramdisk_blk", "blk",
37 				 IF_TYPE_RAMDISK, 0, 512, 0, &bdev);
38 	if (ret) {
39 		debug("Can't create block device\n");
40 		return ret;
41 	}
42 
43 	return 0;
44 }
45 
46 static const struct ramdisk_ops ramdisk_ro_ops = {
47 	.read = ramdisk_ro_bread,
48 };
49 
50 static const struct udevice_id ramdisk_ro_ids[] = {
51 	{ .compatible = "ramdisk-ro" },
52 	{ }
53 };
54 
55 U_BOOT_DRIVER(ramdisk_ro) = {
56 	.name		= "ramdisk-ro",
57 	.id		= UCLASS_RAMDISK,
58 	.ops		= &ramdisk_ro_ops,
59 	.of_match	= ramdisk_ro_ids,
60 	.bind		= ramdisk_ro_bind,
61 };
62