xref: /openbmc/u-boot/arch/x86/lib/zimage.c (revision 4519668b)
1 /*
2  * Copyright (c) 2011 The Chromium OS Authors.
3  * (C) Copyright 2002
4  * Daniel Engström, Omicron Ceti AB, <daniel@omicron.se>
5  *
6  * SPDX-License-Identifier:	GPL-2.0+
7  */
8 
9 /*
10  * Linux x86 zImage and bzImage loading
11  *
12  * based on the procdure described in
13  * linux/Documentation/i386/boot.txt
14  */
15 
16 #include <common.h>
17 #include <asm/io.h>
18 #include <asm/ptrace.h>
19 #include <asm/zimage.h>
20 #include <asm/byteorder.h>
21 #include <asm/bootm.h>
22 #include <asm/bootparam.h>
23 #ifdef CONFIG_SYS_COREBOOT
24 #include <asm/arch/timestamp.h>
25 #endif
26 #include <linux/compiler.h>
27 
28 DECLARE_GLOBAL_DATA_PTR;
29 
30 /*
31  * Memory lay-out:
32  *
33  * relative to setup_base (which is 0x90000 currently)
34  *
35  *	0x0000-0x7FFF	Real mode kernel
36  *	0x8000-0x8FFF	Stack and heap
37  *	0x9000-0x90FF	Kernel command line
38  */
39 #define DEFAULT_SETUP_BASE	0x90000
40 #define COMMAND_LINE_OFFSET	0x9000
41 #define HEAP_END_OFFSET		0x8e00
42 
43 #define COMMAND_LINE_SIZE	2048
44 
45 /*
46  * Install a default e820 table with 3 entries as follows:
47  *
48  *	0x000000-0x0a0000	Useable RAM
49  *	0x0a0000-0x100000	Reserved for ISA
50  *	0x100000-gd->ram_size	Useable RAM
51  */
52 __weak unsigned install_e820_map(unsigned max_entries,
53 				 struct e820entry *entries)
54 {
55 	entries[0].addr = 0;
56 	entries[0].size = ISA_START_ADDRESS;
57 	entries[0].type = E820_RAM;
58 	entries[1].addr = ISA_START_ADDRESS;
59 	entries[1].size = ISA_END_ADDRESS - ISA_START_ADDRESS;
60 	entries[1].type = E820_RESERVED;
61 	entries[2].addr = ISA_END_ADDRESS;
62 	entries[2].size = gd->ram_size - ISA_END_ADDRESS;
63 	entries[2].type = E820_RAM;
64 	entries[3].addr = CONFIG_PCIE_ECAM_BASE;
65 	entries[3].size = CONFIG_PCIE_ECAM_SIZE;
66 	entries[3].type = E820_RESERVED;
67 
68 	return 4;
69 }
70 
71 static void build_command_line(char *command_line, int auto_boot)
72 {
73 	char *env_command_line;
74 
75 	command_line[0] = '\0';
76 
77 	env_command_line =  getenv("bootargs");
78 
79 	/* set console= argument if we use a serial console */
80 	if (!strstr(env_command_line, "console=")) {
81 		if (!strcmp(getenv("stdout"), "serial")) {
82 
83 			/* We seem to use serial console */
84 			sprintf(command_line, "console=ttyS0,%s ",
85 				getenv("baudrate"));
86 		}
87 	}
88 
89 	if (auto_boot)
90 		strcat(command_line, "auto ");
91 
92 	if (env_command_line)
93 		strcat(command_line, env_command_line);
94 
95 	printf("Kernel command line: \"%s\"\n", command_line);
96 }
97 
98 static int kernel_magic_ok(struct setup_header *hdr)
99 {
100 	if (KERNEL_MAGIC != hdr->boot_flag) {
101 		printf("Error: Invalid Boot Flag "
102 			"(found 0x%04x, expected 0x%04x)\n",
103 			hdr->boot_flag, KERNEL_MAGIC);
104 		return 0;
105 	} else {
106 		printf("Valid Boot Flag\n");
107 		return 1;
108 	}
109 }
110 
111 static int get_boot_protocol(struct setup_header *hdr)
112 {
113 	if (hdr->header == KERNEL_V2_MAGIC) {
114 		printf("Magic signature found\n");
115 		return hdr->version;
116 	} else {
117 		/* Very old kernel */
118 		printf("Magic signature not found\n");
119 		return 0x0100;
120 	}
121 }
122 
123 struct boot_params *load_zimage(char *image, unsigned long kernel_size,
124 				ulong *load_addressp)
125 {
126 	struct boot_params *setup_base;
127 	int setup_size;
128 	int bootproto;
129 	int big_image;
130 
131 	struct boot_params *params = (struct boot_params *)image;
132 	struct setup_header *hdr = &params->hdr;
133 
134 	/* base address for real-mode segment */
135 	setup_base = (struct boot_params *)DEFAULT_SETUP_BASE;
136 
137 	if (!kernel_magic_ok(hdr))
138 		return 0;
139 
140 	/* determine size of setup */
141 	if (0 == hdr->setup_sects) {
142 		printf("Setup Sectors = 0 (defaulting to 4)\n");
143 		setup_size = 5 * 512;
144 	} else {
145 		setup_size = (hdr->setup_sects + 1) * 512;
146 	}
147 
148 	printf("Setup Size = 0x%8.8lx\n", (ulong)setup_size);
149 
150 	if (setup_size > SETUP_MAX_SIZE)
151 		printf("Error: Setup is too large (%d bytes)\n", setup_size);
152 
153 	/* determine boot protocol version */
154 	bootproto = get_boot_protocol(hdr);
155 
156 	printf("Using boot protocol version %x.%02x\n",
157 	       (bootproto & 0xff00) >> 8, bootproto & 0xff);
158 
159 	if (bootproto >= 0x0200) {
160 		if (hdr->setup_sects >= 15) {
161 			printf("Linux kernel version %s\n",
162 				(char *)params +
163 				hdr->kernel_version + 0x200);
164 		} else {
165 			printf("Setup Sectors < 15 - "
166 				"Cannot print kernel version.\n");
167 		}
168 	}
169 
170 	/* Determine image type */
171 	big_image = (bootproto >= 0x0200) &&
172 		    (hdr->loadflags & BIG_KERNEL_FLAG);
173 
174 	/* Determine load address */
175 	if (big_image)
176 		*load_addressp = BZIMAGE_LOAD_ADDR;
177 	else
178 		*load_addressp = ZIMAGE_LOAD_ADDR;
179 
180 	printf("Building boot_params at 0x%8.8lx\n", (ulong)setup_base);
181 	memset(setup_base, 0, sizeof(*setup_base));
182 	setup_base->hdr = params->hdr;
183 
184 	if (bootproto >= 0x0204)
185 		kernel_size = hdr->syssize * 16;
186 	else
187 		kernel_size -= setup_size;
188 
189 	if (bootproto == 0x0100) {
190 		/*
191 		 * A very old kernel MUST have its real-mode code
192 		 * loaded at 0x90000
193 		 */
194 		if ((u32)setup_base != 0x90000) {
195 			/* Copy the real-mode kernel */
196 			memmove((void *)0x90000, setup_base, setup_size);
197 
198 			/* Copy the command line */
199 			memmove((void *)0x99000,
200 				(u8 *)setup_base + COMMAND_LINE_OFFSET,
201 				COMMAND_LINE_SIZE);
202 
203 			 /* Relocated */
204 			setup_base = (struct boot_params *)0x90000;
205 		}
206 
207 		/* It is recommended to clear memory up to the 32K mark */
208 		memset((u8 *)0x90000 + setup_size, 0,
209 		       SETUP_MAX_SIZE - setup_size);
210 	}
211 
212 	if (big_image) {
213 		if (kernel_size > BZIMAGE_MAX_SIZE) {
214 			printf("Error: bzImage kernel too big! "
215 				"(size: %ld, max: %d)\n",
216 				kernel_size, BZIMAGE_MAX_SIZE);
217 			return 0;
218 		}
219 	} else if ((kernel_size) > ZIMAGE_MAX_SIZE) {
220 		printf("Error: zImage kernel too big! (size: %ld, max: %d)\n",
221 		       kernel_size, ZIMAGE_MAX_SIZE);
222 		return 0;
223 	}
224 
225 	printf("Loading %s at address %lx (%ld bytes)\n",
226 	       big_image ? "bzImage" : "zImage", *load_addressp, kernel_size);
227 
228 	memmove((void *)*load_addressp, image + setup_size, kernel_size);
229 
230 	return setup_base;
231 }
232 
233 int setup_zimage(struct boot_params *setup_base, char *cmd_line, int auto_boot,
234 		 unsigned long initrd_addr, unsigned long initrd_size)
235 {
236 	struct setup_header *hdr = &setup_base->hdr;
237 	int bootproto = get_boot_protocol(hdr);
238 
239 	setup_base->e820_entries = install_e820_map(
240 		ARRAY_SIZE(setup_base->e820_map), setup_base->e820_map);
241 
242 	if (bootproto == 0x0100) {
243 		setup_base->screen_info.cl_magic = COMMAND_LINE_MAGIC;
244 		setup_base->screen_info.cl_offset = COMMAND_LINE_OFFSET;
245 	}
246 	if (bootproto >= 0x0200) {
247 		hdr->type_of_loader = 8;
248 
249 		if (initrd_addr) {
250 			printf("Initial RAM disk at linear address "
251 			       "0x%08lx, size %ld bytes\n",
252 			       initrd_addr, initrd_size);
253 
254 			hdr->ramdisk_image = initrd_addr;
255 			hdr->ramdisk_size = initrd_size;
256 		}
257 	}
258 
259 	if (bootproto >= 0x0201) {
260 		hdr->heap_end_ptr = HEAP_END_OFFSET;
261 		hdr->loadflags |= HEAP_FLAG;
262 	}
263 
264 	if (cmd_line) {
265 		if (bootproto >= 0x0202) {
266 			hdr->cmd_line_ptr = (uintptr_t)cmd_line;
267 		} else if (bootproto >= 0x0200) {
268 			setup_base->screen_info.cl_magic = COMMAND_LINE_MAGIC;
269 			setup_base->screen_info.cl_offset =
270 				(uintptr_t)cmd_line - (uintptr_t)setup_base;
271 
272 			hdr->setup_move_size = 0x9100;
273 		}
274 
275 		/* build command line at COMMAND_LINE_OFFSET */
276 		build_command_line(cmd_line, auto_boot);
277 	}
278 
279 	setup_video(&setup_base->screen_info);
280 
281 	return 0;
282 }
283 
284 void setup_pcat_compatibility(void)
285 	__attribute__((weak, alias("__setup_pcat_compatibility")));
286 
287 void __setup_pcat_compatibility(void)
288 {
289 }
290 
291 int do_zboot(cmd_tbl_t *cmdtp, int flag, int argc, char *const argv[])
292 {
293 	struct boot_params *base_ptr;
294 	void *bzImage_addr = NULL;
295 	ulong load_address;
296 	char *s;
297 	ulong bzImage_size = 0;
298 	ulong initrd_addr = 0;
299 	ulong initrd_size = 0;
300 
301 	disable_interrupts();
302 
303 	/* Setup board for maximum PC/AT Compatibility */
304 	setup_pcat_compatibility();
305 
306 	if (argc >= 2) {
307 		/* argv[1] holds the address of the bzImage */
308 		s = argv[1];
309 	} else {
310 		s = getenv("fileaddr");
311 	}
312 
313 	if (s)
314 		bzImage_addr = (void *)simple_strtoul(s, NULL, 16);
315 
316 	if (argc >= 3) {
317 		/* argv[2] holds the size of the bzImage */
318 		bzImage_size = simple_strtoul(argv[2], NULL, 16);
319 	}
320 
321 	if (argc >= 4)
322 		initrd_addr = simple_strtoul(argv[3], NULL, 16);
323 	if (argc >= 5)
324 		initrd_size = simple_strtoul(argv[4], NULL, 16);
325 
326 	/* Lets look for */
327 	base_ptr = load_zimage(bzImage_addr, bzImage_size, &load_address);
328 
329 	if (!base_ptr) {
330 		puts("## Kernel loading failed ...\n");
331 		return -1;
332 	}
333 	if (setup_zimage(base_ptr, (char *)base_ptr + COMMAND_LINE_OFFSET,
334 			0, initrd_addr, initrd_size)) {
335 		puts("Setting up boot parameters failed ...\n");
336 		return -1;
337 	}
338 
339 	/* we assume that the kernel is in place */
340 	return boot_linux_kernel((ulong)base_ptr, load_address, false);
341 }
342 
343 U_BOOT_CMD(
344 	zboot, 5, 0,	do_zboot,
345 	"Boot bzImage",
346 	"[addr] [size] [initrd addr] [initrd size]\n"
347 	"      addr -        The optional starting address of the bzimage.\n"
348 	"                    If not set it defaults to the environment\n"
349 	"                    variable \"fileaddr\".\n"
350 	"      size -        The optional size of the bzimage. Defaults to\n"
351 	"                    zero.\n"
352 	"      initrd addr - The address of the initrd image to use, if any.\n"
353 	"      initrd size - The size of the initrd image to use, if any.\n"
354 );
355