1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * (C) Copyright 2018 Arm Ltd.
4 */
5
6#include "imagetool.h"
7#include <image.h>
8
9#include <sunxi_image.h>
10
11/*
12 * NAND requires 8K padding. SD/eMMC gets away with 512 bytes,
13 * but let's use the larger padding by default to cover both.
14 */
15#define PAD_SIZE			8192
16#define PAD_SIZE_MIN			512
17
18static int egon_get_arch(struct image_tool_params *params)
19{
20	if (params->Aflag)
21		return params->arch;
22
23	/* For compatibility, assume ARM when no architecture specified */
24	return IH_ARCH_ARM;
25}
26
27static int egon_check_params(struct image_tool_params *params)
28{
29	/*
30	 * Check whether the architecture is supported.
31	 */
32	switch (egon_get_arch(params)) {
33	case IH_ARCH_ARM:
34	case IH_ARCH_RISCV:
35		break;
36	default:
37		return EXIT_FAILURE;
38	}
39
40	/* We need a binary image file. */
41	return !params->dflag;
42}
43
44static int egon_verify_header(unsigned char *ptr, int image_size,
45			      struct image_tool_params *params)
46{
47	const struct boot_file_head *header = (void *)ptr;
48	uint32_t length;
49
50	/*
51	 * First 4 bytes must be a branch instruction of the corresponding
52	 * architecture.
53	 */
54	switch (egon_get_arch(params)) {
55	case IH_ARCH_ARM:
56		if ((le32_to_cpu(header->b_instruction) & 0xff000000) != 0xea000000)
57			return EXIT_FAILURE;
58		break;
59	case IH_ARCH_RISCV:
60		if ((le32_to_cpu(header->b_instruction) & 0x00000fff) != 0x0000006f)
61			return EXIT_FAILURE;
62		break;
63	default:
64		return EXIT_FAILURE; /* Unknown architecture */
65	}
66
67	if (memcmp(header->magic, BOOT0_MAGIC, sizeof(header->magic)))
68		return EXIT_FAILURE;
69
70	length = le32_to_cpu(header->length);
71	/* Must be at least 512 byte aligned. */
72	if (length & 511)
73		return EXIT_FAILURE;
74
75	/*
76	 * Image could also contain U-Boot proper, so could be bigger.
77	 * But it must not be shorter.
78	 */
79	if (image_size < length)
80		return EXIT_FAILURE;
81
82	return EXIT_SUCCESS;
83}
84
85static void egon_print_header(const void *buf, struct image_tool_params *params)
86{
87	const struct boot_file_head *header = buf;
88
89	printf("Allwinner eGON image, size: %d bytes\n",
90	       le32_to_cpu(header->length));
91
92	if (memcmp(header->spl_signature, SPL_SIGNATURE, 3))
93		return;
94
95	printf("\tSPL header version %d.%d\n",
96	       header->spl_signature[3] >> SPL_MINOR_BITS,
97	       header->spl_signature[3] & ((1U << SPL_MINOR_BITS) - 1));
98	if (header->spl_signature[3] >= SPL_DT_HEADER_VERSION) {
99		uint32_t dt_name_offs = le32_to_cpu(header->dt_name_offset);
100
101		if (dt_name_offs > 0)
102			printf("\tDT name: %s\n", (char *)buf + dt_name_offs);
103	}
104}
105
106static void egon_set_header(void *buf, struct stat *sbuf, int infd,
107			    struct image_tool_params *params)
108{
109	struct boot_file_head *header = buf;
110	uint32_t *buf32 = buf;
111	uint32_t checksum = 0, value;
112	int i;
113
114	/*
115	 * Different architectures need different first instruction to
116	 * branch to the body.
117	 */
118	switch (egon_get_arch(params)) {
119	case IH_ARCH_ARM:
120		/* Generate an ARM branch instruction to jump over the header. */
121		value = 0xea000000 | (sizeof(struct boot_file_head) / 4 - 2);
122		header->b_instruction = cpu_to_le32(value);
123		break;
124	case IH_ARCH_RISCV:
125		/*
126		 * Generate a RISC-V JAL instruction with rd=x0
127		 * (pseudo instruction J, jump without side effects).
128		 *
129		 * The following weird bit operation maps imm[20]
130		 * to inst[31], imm[10:1] to inst[30:21],
131		 * imm[11] to inst[20], imm[19:12] to inst[19:12],
132		 * and imm[0] is dropped (because 1-byte RISC-V instruction
133		 * is not allowed).
134		 */
135		value = 0x0000006f |
136			((sizeof(struct boot_file_head) & 0x00100000) << 11) |
137			((sizeof(struct boot_file_head) & 0x000007fe) << 20) |
138			((sizeof(struct boot_file_head) & 0x00000800) << 9) |
139			((sizeof(struct boot_file_head) & 0x000ff000) << 0);
140		header->b_instruction = cpu_to_le32(value);
141		break;
142	}
143
144	memcpy(header->magic, BOOT0_MAGIC, sizeof(header->magic));
145	header->check_sum = cpu_to_le32(BROM_STAMP_VALUE);
146	header->length = cpu_to_le32(params->file_size);
147
148	memcpy(header->spl_signature, SPL_SIGNATURE, 3);
149	header->spl_signature[3] = SPL_ENV_HEADER_VERSION;
150
151	/* If an image name has been provided, use it as the DT name. */
152	if (params->imagename && params->imagename[0]) {
153		if (strlen(params->imagename) > sizeof(header->string_pool) - 1)
154			printf("WARNING: DT name too long for SPL header!\n");
155		else {
156			strcpy((char *)header->string_pool, params->imagename);
157			value = offsetof(struct boot_file_head, string_pool);
158			header->dt_name_offset = cpu_to_le32(value);
159			header->spl_signature[3] = SPL_DT_HEADER_VERSION;
160		}
161	}
162
163	/* Calculate the checksum. Yes, it's that simple. */
164	for (i = 0; i < sbuf->st_size / 4; i++)
165		checksum += le32_to_cpu(buf32[i]);
166	header->check_sum = cpu_to_le32(checksum);
167}
168
169static int egon_check_image_type(uint8_t type)
170{
171	return type == IH_TYPE_SUNXI_EGON ? 0 : 1;
172}
173
174static int egon_vrec_header(struct image_tool_params *params,
175			    struct image_type_params *tparams)
176{
177	int pad_size = ALIGN(params->bl_len ?: PAD_SIZE, PAD_SIZE_MIN);
178
179	tparams->hdr = calloc(sizeof(struct boot_file_head), 1);
180
181	/* Return padding to complete blocks. */
182	return ALIGN(params->file_size, pad_size) - params->file_size;
183}
184
185U_BOOT_IMAGE_TYPE(
186	sunxi_egon,
187	"Allwinner eGON Boot Image support",
188	sizeof(struct boot_file_head),
189	NULL,
190	egon_check_params,
191	egon_verify_header,
192	egon_print_header,
193	egon_set_header,
194	NULL,
195	egon_check_image_type,
196	NULL,
197	egon_vrec_header
198);
199