1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * Copyright 2023 Linus Walleij <linus.walleij@linaro.org>
4 * Support for the "SEAttle iMAge" SEAMA NAND image format
5 */
6
7#include <common.h>
8#include <command.h>
9#include <nand.h>
10
11/*
12 * All SEAMA data is stored in the flash in "network endianness"
13 * i.e. big endian, which means that it needs to be byte-swapped
14 * on all little endian platforms.
15 *
16 * structure for a SEAMA entity in NAND flash:
17 *
18 * 32 bit SEAMA magic 0x5EA3A417
19 * 16 bit reserved
20 * 16 bit metadata size (following the header)
21 * 32 bit image size
22 * 16 bytes MD5 digest of the image
23 * meta data
24 * ... image data ...
25 *
26 * Then if a new SEAMA magic follows, that is the next image.
27 */
28
29#define SEAMA_MAGIC		0x5EA3A417
30#define SEAMA_HDR_NO_META_SZ	28
31#define SEAMA_MAX_META_SZ	(1024 - SEAMA_HDR_NO_META_SZ)
32
33struct seama_header {
34	u32 magic;
35	u32 meta_size;
36	u32 image_size;
37	u8 md5[16];
38	u8 metadata[SEAMA_MAX_META_SZ];
39};
40
41static struct seama_header shdr;
42
43static int env_set_val(const char *varname, ulong val)
44{
45	int ret;
46
47	ret = env_set_hex(varname, val);
48	if (ret)
49		printf("Failed to %s env var\n", varname);
50
51	return ret;
52}
53
54static int do_seama_load_image(struct cmd_tbl *cmdtp, int flag, int argc,
55			       char *const argv[])
56{
57	struct mtd_info *mtd;
58	uintptr_t load_addr;
59	unsigned long image_index;
60	u32 len;
61	size_t readsz;
62	int ret;
63	u32 *start;
64	u32 *offset;
65	u32 *end;
66	u32 tmp;
67
68	if (argc < 2 || argc > 3)
69		return CMD_RET_USAGE;
70
71	load_addr = hextoul(argv[1], NULL);
72	if (!load_addr) {
73		printf("Invalid load address\n");
74		return CMD_RET_USAGE;
75	}
76
77	/* Can be 0 for first image */
78	image_index = hextoul(argv[2], NULL);
79
80	/* We only support one NAND, the first one */
81	nand_curr_device = 0;
82	mtd = get_nand_dev_by_index(0);
83	if (!mtd) {
84		printf("NAND Device 0 not available\n");
85		return CMD_RET_FAILURE;
86	}
87
88#ifdef CONFIG_SYS_NAND_SELECT_DEVICE
89	board_nand_select_device(mtd_to_nand(mtd), 0);
90#endif
91
92	printf("Loading SEAMA image %lu from %s\n", image_index, mtd->name);
93
94	readsz = sizeof(shdr);
95	offset = 0;
96	ret = nand_read_skip_bad(mtd, 0, &readsz, NULL, mtd->size,
97				 (u_char *)&shdr);
98	if (ret) {
99		printf("Read error reading SEAMA header\n");
100		return CMD_RET_FAILURE;
101	}
102
103	if (shdr.magic != SEAMA_MAGIC) {
104		printf("Invalid SEAMA image magic: 0x%08x\n", shdr.magic);
105		return CMD_RET_FAILURE;
106	}
107
108	/* Only the lower 16 bits are valid */
109	shdr.meta_size &= 0xFFFF;
110
111	if (env_set_val("seama_image_size", 0))
112		return CMD_RET_FAILURE;
113
114	printf("SEMA IMAGE:\n");
115	printf("  metadata size %d\n", shdr.meta_size);
116	printf("  image size %d\n", shdr.image_size);
117	printf("  checksum %02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x\n",
118	       shdr.md5[0], shdr.md5[1], shdr.md5[2], shdr.md5[3],
119	       shdr.md5[4], shdr.md5[5], shdr.md5[6], shdr.md5[7],
120	       shdr.md5[8], shdr.md5[9], shdr.md5[10], shdr.md5[11],
121	       shdr.md5[12], shdr.md5[13], shdr.md5[14], shdr.md5[15]);
122
123	/* TODO: handle metadata if needed */
124
125	len = shdr.image_size;
126	if (env_set_val("seama_image_size", len))
127		return CMD_RET_FAILURE;
128
129	/* We need to include the header (read full pages) */
130	readsz = shdr.image_size + SEAMA_HDR_NO_META_SZ + shdr.meta_size;
131	ret = nand_read_skip_bad(mtd, 0, &readsz, NULL, mtd->size,
132				 (u_char *)load_addr);
133	if (ret) {
134		printf("Read error reading SEAMA main image\n");
135		return CMD_RET_FAILURE;
136	}
137
138	/* We use a temporary variable tmp to avoid to hairy casts */
139	start = (u32 *)load_addr;
140	tmp = (u32)start;
141	tmp += SEAMA_HDR_NO_META_SZ + shdr.meta_size;
142	offset = (u32 *)tmp;
143	tmp += shdr.image_size;
144	end = (u32 *)tmp;
145
146	printf("Decoding SEAMA image 0x%08x..0x%08x to 0x%08x\n",
147	       (u32)offset, (u32)end, (u32)start);
148	for (; start < end; start++, offset++)
149		*start = be32_to_cpu(*offset);
150
151	return CMD_RET_SUCCESS;
152}
153
154U_BOOT_CMD
155	(seama, 3, 1, do_seama_load_image,
156	 "Load the SEAMA image and sets envs",
157	 "seama <addr> <imageindex>\n"
158);
159