xref: /openbmc/u-boot/cmd/bootefi.c (revision 679590eb)
1 /*
2  *  EFI application loader
3  *
4  *  Copyright (c) 2016 Alexander Graf
5  *
6  *  SPDX-License-Identifier:     GPL-2.0+
7  */
8 
9 #include <common.h>
10 #include <command.h>
11 #include <dm.h>
12 #include <efi_loader.h>
13 #include <errno.h>
14 #include <libfdt.h>
15 #include <libfdt_env.h>
16 #include <memalign.h>
17 #include <asm/global_data.h>
18 #include <asm-generic/sections.h>
19 #include <linux/linkage.h>
20 
21 DECLARE_GLOBAL_DATA_PTR;
22 
23 static uint8_t efi_obj_list_initalized;
24 
25 /*
26  * When booting using the "bootefi" command, we don't know which
27  * physical device the file came from. So we create a pseudo-device
28  * called "bootefi" with the device path /bootefi.
29  *
30  * In addition to the originating device we also declare the file path
31  * of "bootefi" based loads to be /bootefi.
32  */
33 static struct efi_device_path_file_path bootefi_image_path[] = {
34 	{
35 		.dp.type = DEVICE_PATH_TYPE_MEDIA_DEVICE,
36 		.dp.sub_type = DEVICE_PATH_SUB_TYPE_FILE_PATH,
37 		.dp.length = sizeof(bootefi_image_path[0]),
38 		.str = { 'b','o','o','t','e','f','i' },
39 	}, {
40 		.dp.type = DEVICE_PATH_TYPE_END,
41 		.dp.sub_type = DEVICE_PATH_SUB_TYPE_END,
42 		.dp.length = sizeof(bootefi_image_path[0]),
43 	}
44 };
45 
46 static struct efi_device_path_file_path bootefi_device_path[] = {
47 	{
48 		.dp.type = DEVICE_PATH_TYPE_MEDIA_DEVICE,
49 		.dp.sub_type = DEVICE_PATH_SUB_TYPE_FILE_PATH,
50 		.dp.length = sizeof(bootefi_image_path[0]),
51 		.str = { 'b','o','o','t','e','f','i' },
52 	}, {
53 		.dp.type = DEVICE_PATH_TYPE_END,
54 		.dp.sub_type = DEVICE_PATH_SUB_TYPE_END,
55 		.dp.length = sizeof(bootefi_image_path[0]),
56 	}
57 };
58 
59 /* The EFI loaded_image interface for the image executed via "bootefi" */
60 static struct efi_loaded_image loaded_image_info = {
61 	.device_handle = bootefi_device_path,
62 	.file_path = bootefi_image_path,
63 };
64 
65 /* The EFI object struct for the image executed via "bootefi" */
66 static struct efi_object loaded_image_info_obj = {
67 	.handle = &loaded_image_info,
68 	.protocols = {
69 		{
70 			/*
71 			 * When asking for the loaded_image interface, just
72 			 * return handle which points to loaded_image_info
73 			 */
74 			.guid = &efi_guid_loaded_image,
75 			.protocol_interface = &loaded_image_info,
76 		},
77 		{
78 			/*
79 			 * When asking for the device path interface, return
80 			 * bootefi_device_path
81 			 */
82 			.guid = &efi_guid_device_path,
83 			.protocol_interface = bootefi_device_path,
84 		},
85 		{
86 			.guid = &efi_guid_console_control,
87 			.protocol_interface = (void *) &efi_console_control
88 		},
89 		{
90 			.guid = &efi_guid_device_path_to_text_protocol,
91 			.protocol_interface = (void *) &efi_device_path_to_text
92 		},
93 	},
94 };
95 
96 /* The EFI object struct for the device the "bootefi" image was loaded from */
97 static struct efi_object bootefi_device_obj = {
98 	.handle = bootefi_device_path,
99 	.protocols = {
100 		{
101 			/* When asking for the device path interface, return
102 			 * bootefi_device_path */
103 			.guid = &efi_guid_device_path,
104 			.protocol_interface = bootefi_device_path
105 		}
106 	},
107 };
108 
109 /* Initialize and populate EFI object list */
110 static void efi_init_obj_list(void)
111 {
112 	efi_obj_list_initalized = 1;
113 
114 	list_add_tail(&loaded_image_info_obj.link, &efi_obj_list);
115 	list_add_tail(&bootefi_device_obj.link, &efi_obj_list);
116 	efi_console_register();
117 #ifdef CONFIG_PARTITIONS
118 	efi_disk_register();
119 #endif
120 #if defined(CONFIG_LCD) || defined(CONFIG_DM_VIDEO)
121 	efi_gop_register();
122 #endif
123 #ifdef CONFIG_NET
124 	void *nethandle = loaded_image_info.device_handle;
125 	efi_net_register(&nethandle);
126 
127 	if (!memcmp(bootefi_device_path[0].str, "N\0e\0t", 6))
128 		loaded_image_info.device_handle = nethandle;
129 	else
130 		loaded_image_info.device_handle = bootefi_device_path;
131 #endif
132 #ifdef CONFIG_GENERATE_SMBIOS_TABLE
133 	efi_smbios_register();
134 #endif
135 
136 	/* Initialize EFI runtime services */
137 	efi_reset_system_init();
138 	efi_get_time_init();
139 }
140 
141 static void *copy_fdt(void *fdt)
142 {
143 	u64 fdt_size = fdt_totalsize(fdt);
144 	unsigned long fdt_ram_start = -1L, fdt_pages;
145 	u64 new_fdt_addr;
146 	void *new_fdt;
147 	int i;
148 
149         for (i = 0; i < CONFIG_NR_DRAM_BANKS; i++) {
150                 u64 ram_start = gd->bd->bi_dram[i].start;
151                 u64 ram_size = gd->bd->bi_dram[i].size;
152 
153 		if (!ram_size)
154 			continue;
155 
156 		if (ram_start < fdt_ram_start)
157 			fdt_ram_start = ram_start;
158 	}
159 
160 	/* Give us at least 4kb breathing room */
161 	fdt_size = ALIGN(fdt_size + 4096, 4096);
162 	fdt_pages = fdt_size >> EFI_PAGE_SHIFT;
163 
164 	/* Safe fdt location is at 128MB */
165 	new_fdt_addr = fdt_ram_start + (128 * 1024 * 1024) + fdt_size;
166 	if (efi_allocate_pages(1, EFI_BOOT_SERVICES_DATA, fdt_pages,
167 			       &new_fdt_addr) != EFI_SUCCESS) {
168 		/* If we can't put it there, put it somewhere */
169 		new_fdt_addr = (ulong)memalign(4096, fdt_size);
170 		if (efi_allocate_pages(1, EFI_BOOT_SERVICES_DATA, fdt_pages,
171 				       &new_fdt_addr) != EFI_SUCCESS) {
172 			printf("ERROR: Failed to reserve space for FDT\n");
173 			return NULL;
174 		}
175 	}
176 
177 	new_fdt = (void*)(ulong)new_fdt_addr;
178 	memcpy(new_fdt, fdt, fdt_totalsize(fdt));
179 	fdt_set_totalsize(new_fdt, fdt_size);
180 
181 	return new_fdt;
182 }
183 
184 static ulong efi_do_enter(void *image_handle,
185 			  struct efi_system_table *st,
186 			  asmlinkage ulong (*entry)(void *image_handle,
187 				struct efi_system_table *st))
188 {
189 	efi_status_t ret = EFI_LOAD_ERROR;
190 
191 	if (entry)
192 		ret = entry(image_handle, st);
193 	st->boottime->exit(image_handle, ret, 0, NULL);
194 	return ret;
195 }
196 
197 #ifdef CONFIG_ARM64
198 static unsigned long efi_run_in_el2(asmlinkage ulong (*entry)(
199 			void *image_handle, struct efi_system_table *st),
200 			void *image_handle, struct efi_system_table *st)
201 {
202 	/* Enable caches again */
203 	dcache_enable();
204 
205 	return efi_do_enter(image_handle, st, entry);
206 }
207 #endif
208 
209 /*
210  * Load an EFI payload into a newly allocated piece of memory, register all
211  * EFI objects it would want to access and jump to it.
212  */
213 static unsigned long do_bootefi_exec(void *efi, void *fdt)
214 {
215 	ulong (*entry)(void *image_handle, struct efi_system_table *st)
216 		asmlinkage;
217 	ulong fdt_pages, fdt_size, fdt_start, fdt_end;
218 	const efi_guid_t fdt_guid = EFI_FDT_GUID;
219 	bootm_headers_t img = { 0 };
220 
221 	/*
222 	 * gd lives in a fixed register which may get clobbered while we execute
223 	 * the payload. So save it here and restore it on every callback entry
224 	 */
225 	efi_save_gd();
226 
227 	if (fdt && !fdt_check_header(fdt)) {
228 		/* Prepare fdt for payload */
229 		fdt = copy_fdt(fdt);
230 
231 		if (image_setup_libfdt(&img, fdt, 0, NULL)) {
232 			printf("ERROR: Failed to process device tree\n");
233 			return -EINVAL;
234 		}
235 
236 		/* Link to it in the efi tables */
237 		efi_install_configuration_table(&fdt_guid, fdt);
238 
239 		/* And reserve the space in the memory map */
240 		fdt_start = ((ulong)fdt) & ~EFI_PAGE_MASK;
241 		fdt_end = ((ulong)fdt) + fdt_totalsize(fdt);
242 		fdt_size = (fdt_end - fdt_start) + EFI_PAGE_MASK;
243 		fdt_pages = fdt_size >> EFI_PAGE_SHIFT;
244 		/* Give a bootloader the chance to modify the device tree */
245 		fdt_pages += 2;
246 		efi_add_memory_map(fdt_start, fdt_pages,
247 				   EFI_BOOT_SERVICES_DATA, true);
248 	} else {
249 		printf("WARNING: Invalid device tree, expect boot to fail\n");
250 		efi_install_configuration_table(&fdt_guid, NULL);
251 	}
252 
253 	/* Load the EFI payload */
254 	entry = efi_load_pe(efi, &loaded_image_info);
255 	if (!entry)
256 		return -ENOENT;
257 
258 	/* Initialize and populate EFI object list */
259 	if (!efi_obj_list_initalized)
260 		efi_init_obj_list();
261 
262 	/* Call our payload! */
263 	debug("%s:%d Jumping to 0x%lx\n", __func__, __LINE__, (long)entry);
264 
265 	if (setjmp(&loaded_image_info.exit_jmp)) {
266 		return loaded_image_info.exit_status;
267 	}
268 
269 #ifdef CONFIG_ARM64
270 	/* On AArch64 we need to make sure we call our payload in < EL3 */
271 	if (current_el() == 3) {
272 		smp_kick_all_cpus();
273 		dcache_disable();	/* flush cache before switch to EL2 */
274 
275 		/* Move into EL2 and keep running there */
276 		armv8_switch_to_el2((ulong)entry, (ulong)&loaded_image_info,
277 				    (ulong)&systab, 0, (ulong)efi_run_in_el2,
278 				    ES_TO_AARCH64);
279 
280 		/* Should never reach here, efi exits with longjmp */
281 		while (1) { }
282 	}
283 #endif
284 
285 	return efi_do_enter(&loaded_image_info, &systab, entry);
286 }
287 
288 
289 /* Interpreter command to boot an arbitrary EFI image from memory */
290 static int do_bootefi(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
291 {
292 	char *saddr, *sfdt;
293 	unsigned long addr, fdt_addr = 0;
294 	unsigned long r;
295 
296 	if (argc < 2)
297 		return CMD_RET_USAGE;
298 #ifdef CONFIG_CMD_BOOTEFI_HELLO
299 	if (!strcmp(argv[1], "hello")) {
300 		ulong size = __efi_hello_world_end - __efi_hello_world_begin;
301 
302 		addr = CONFIG_SYS_LOAD_ADDR;
303 		memcpy((char *)addr, __efi_hello_world_begin, size);
304 	} else
305 #endif
306 	{
307 		saddr = argv[1];
308 
309 		addr = simple_strtoul(saddr, NULL, 16);
310 
311 		if (argc > 2) {
312 			sfdt = argv[2];
313 			fdt_addr = simple_strtoul(sfdt, NULL, 16);
314 		}
315 	}
316 
317 	printf("## Starting EFI application at %08lx ...\n", addr);
318 	r = do_bootefi_exec((void *)addr, (void*)fdt_addr);
319 	printf("## Application terminated, r = %lu\n",
320 	       r & ~EFI_ERROR_MASK);
321 
322 	if (r != EFI_SUCCESS)
323 		return 1;
324 	else
325 		return 0;
326 }
327 
328 #ifdef CONFIG_SYS_LONGHELP
329 static char bootefi_help_text[] =
330 	"<image address> [fdt address]\n"
331 	"  - boot EFI payload stored at address <image address>.\n"
332 	"    If specified, the device tree located at <fdt address> gets\n"
333 	"    exposed as EFI configuration table.\n"
334 #ifdef CONFIG_CMD_BOOTEFI_HELLO
335 	"hello\n"
336 	"  - boot a sample Hello World application stored within U-Boot"
337 #endif
338 	;
339 #endif
340 
341 U_BOOT_CMD(
342 	bootefi, 3, 0, do_bootefi,
343 	"Boots an EFI payload from memory",
344 	bootefi_help_text
345 );
346 
347 void efi_set_bootdev(const char *dev, const char *devnr, const char *path)
348 {
349 	__maybe_unused struct blk_desc *desc;
350 	char devname[32] = { 0 }; /* dp->str is u16[32] long */
351 	char *colon, *s;
352 
353 #if defined(CONFIG_BLK) || CONFIG_IS_ENABLED(ISO_PARTITION)
354 	desc = blk_get_dev(dev, simple_strtol(devnr, NULL, 10));
355 #endif
356 
357 #ifdef CONFIG_BLK
358 	if (desc) {
359 		snprintf(devname, sizeof(devname), "%s", desc->bdev->name);
360 	} else
361 #endif
362 
363 	{
364 		/* Assemble the condensed device name we use in efi_disk.c */
365 		snprintf(devname, sizeof(devname), "%s%s", dev, devnr);
366 	}
367 
368 	colon = strchr(devname, ':');
369 
370 #if CONFIG_IS_ENABLED(ISO_PARTITION)
371 	/* For ISOs we create partition block devices */
372 	if (desc && (desc->type != DEV_TYPE_UNKNOWN) &&
373 	    (desc->part_type == PART_TYPE_ISO)) {
374 		if (!colon)
375 			snprintf(devname, sizeof(devname), "%s:1", devname);
376 
377 		colon = NULL;
378 	}
379 #endif
380 
381 	if (colon)
382 		*colon = '\0';
383 
384 	/* Patch bootefi_device_path to the target device */
385 	memset(bootefi_device_path[0].str, 0, sizeof(bootefi_device_path[0].str));
386 	ascii2unicode(bootefi_device_path[0].str, devname);
387 
388 	/* Patch bootefi_image_path to the target file path */
389 	memset(bootefi_image_path[0].str, 0, sizeof(bootefi_image_path[0].str));
390 	if (strcmp(dev, "Net")) {
391 		/* Add leading / to fs paths, because they're absolute */
392 		snprintf(devname, sizeof(devname), "/%s", path);
393 	} else {
394 		snprintf(devname, sizeof(devname), "%s", path);
395 	}
396 	/* DOS style file path: */
397 	s = devname;
398 	while ((s = strchr(s, '/')))
399 		*s++ = '\\';
400 	ascii2unicode(bootefi_image_path[0].str, devname);
401 }
402