xref: /openbmc/u-boot/cmd/bootefi.c (revision 57ade079)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  *  EFI application loader
4  *
5  *  Copyright (c) 2016 Alexander Graf
6  */
7 
8 #include <common.h>
9 #include <bootm.h>
10 #include <charset.h>
11 #include <command.h>
12 #include <dm.h>
13 #include <efi_loader.h>
14 #include <efi_selftest.h>
15 #include <errno.h>
16 #include <linux/libfdt.h>
17 #include <linux/libfdt_env.h>
18 #include <mapmem.h>
19 #include <memalign.h>
20 #include <asm/global_data.h>
21 #include <asm-generic/sections.h>
22 #include <asm-generic/unaligned.h>
23 #include <linux/linkage.h>
24 
25 DECLARE_GLOBAL_DATA_PTR;
26 
27 static struct efi_device_path *bootefi_image_path;
28 static struct efi_device_path *bootefi_device_path;
29 
30 /*
31  * Allow unaligned memory access.
32  *
33  * This routine is overridden by architectures providing this feature.
34  */
35 void __weak allow_unaligned(void)
36 {
37 }
38 
39 /*
40  * Set the load options of an image from an environment variable.
41  *
42  * @loaded_image_info:	the image
43  * @env_var:		name of the environment variable
44  */
45 static void set_load_options(struct efi_loaded_image *loaded_image_info,
46 			     const char *env_var)
47 {
48 	size_t size;
49 	const char *env = env_get(env_var);
50 	u16 *pos;
51 
52 	loaded_image_info->load_options = NULL;
53 	loaded_image_info->load_options_size = 0;
54 	if (!env)
55 		return;
56 	size = utf8_utf16_strlen(env) + 1;
57 	loaded_image_info->load_options = calloc(size, sizeof(u16));
58 	if (!loaded_image_info->load_options) {
59 		printf("ERROR: Out of memory\n");
60 		return;
61 	}
62 	pos = loaded_image_info->load_options;
63 	utf8_utf16_strcpy(&pos, env);
64 	loaded_image_info->load_options_size = size * 2;
65 }
66 
67 /**
68  * copy_fdt() - Copy the device tree to a new location available to EFI
69  *
70  * The FDT is copied to a suitable location within the EFI memory map.
71  * Additional 12 KiB are added to the space in case the device tree needs to be
72  * expanded later with fdt_open_into().
73  *
74  * @fdtp:	On entry a pointer to the flattened device tree.
75  *		On exit a pointer to the copy of the flattened device tree.
76  *		FDT start
77  * Return:	status code
78  */
79 static efi_status_t copy_fdt(void **fdtp)
80 {
81 	unsigned long fdt_ram_start = -1L, fdt_pages;
82 	efi_status_t ret = 0;
83 	void *fdt, *new_fdt;
84 	u64 new_fdt_addr;
85 	uint fdt_size;
86 	int i;
87 
88 	for (i = 0; i < CONFIG_NR_DRAM_BANKS; i++) {
89 		u64 ram_start = gd->bd->bi_dram[i].start;
90 		u64 ram_size = gd->bd->bi_dram[i].size;
91 
92 		if (!ram_size)
93 			continue;
94 
95 		if (ram_start < fdt_ram_start)
96 			fdt_ram_start = ram_start;
97 	}
98 
99 	/*
100 	 * Give us at least 12 KiB of breathing room in case the device tree
101 	 * needs to be expanded later.
102 	 */
103 	fdt = *fdtp;
104 	fdt_pages = efi_size_in_pages(fdt_totalsize(fdt) + 0x3000);
105 	fdt_size = fdt_pages << EFI_PAGE_SHIFT;
106 
107 	/*
108 	 * Safe fdt location is at 127 MiB.
109 	 * On the sandbox convert from the sandbox address space.
110 	 */
111 	new_fdt_addr = (uintptr_t)map_sysmem(fdt_ram_start + 0x7f00000 +
112 					     fdt_size, 0);
113 	ret = efi_allocate_pages(EFI_ALLOCATE_MAX_ADDRESS,
114 				 EFI_RUNTIME_SERVICES_DATA, fdt_pages,
115 				 &new_fdt_addr);
116 	if (ret != EFI_SUCCESS) {
117 		/* If we can't put it there, put it somewhere */
118 		new_fdt_addr = (ulong)memalign(EFI_PAGE_SIZE, fdt_size);
119 		ret = efi_allocate_pages(EFI_ALLOCATE_MAX_ADDRESS,
120 					 EFI_RUNTIME_SERVICES_DATA, fdt_pages,
121 					 &new_fdt_addr);
122 		if (ret != EFI_SUCCESS) {
123 			printf("ERROR: Failed to reserve space for FDT\n");
124 			goto done;
125 		}
126 	}
127 	new_fdt = (void *)(uintptr_t)new_fdt_addr;
128 	memcpy(new_fdt, fdt, fdt_totalsize(fdt));
129 	fdt_set_totalsize(new_fdt, fdt_size);
130 
131 	*fdtp = (void *)(uintptr_t)new_fdt_addr;
132 done:
133 	return ret;
134 }
135 
136 /*
137  * efi_carve_out_dt_rsv() - Carve out DT reserved memory ranges
138  *
139  * The mem_rsv entries of the FDT are added to the memory map. Any failures are
140  * ignored because this is not critical and we would rather continue to try to
141  * boot.
142  *
143  * @fdt: Pointer to device tree
144  */
145 static void efi_carve_out_dt_rsv(void *fdt)
146 {
147 	int nr_rsv, i;
148 	uint64_t addr, size, pages;
149 
150 	nr_rsv = fdt_num_mem_rsv(fdt);
151 
152 	/* Look for an existing entry and add it to the efi mem map. */
153 	for (i = 0; i < nr_rsv; i++) {
154 		if (fdt_get_mem_rsv(fdt, i, &addr, &size) != 0)
155 			continue;
156 
157 		/* Convert from sandbox address space. */
158 		addr = (uintptr_t)map_sysmem(addr, 0);
159 
160 		pages = efi_size_in_pages(size + (addr & EFI_PAGE_MASK));
161 		addr &= ~EFI_PAGE_MASK;
162 		if (!efi_add_memory_map(addr, pages, EFI_RESERVED_MEMORY_TYPE,
163 					false))
164 			printf("FDT memrsv map %d: Failed to add to map\n", i);
165 	}
166 }
167 
168 static efi_status_t efi_install_fdt(ulong fdt_addr)
169 {
170 	bootm_headers_t img = { 0 };
171 	efi_status_t ret;
172 	void *fdt;
173 
174 	fdt = map_sysmem(fdt_addr, 0);
175 	if (fdt_check_header(fdt)) {
176 		printf("ERROR: invalid device tree\n");
177 		return EFI_INVALID_PARAMETER;
178 	}
179 
180 	/* Create memory reservation as indicated by the device tree */
181 	efi_carve_out_dt_rsv(fdt);
182 
183 	/* Prepare fdt for payload */
184 	ret = copy_fdt(&fdt);
185 	if (ret)
186 		return ret;
187 
188 	if (image_setup_libfdt(&img, fdt, 0, NULL)) {
189 		printf("ERROR: failed to process device tree\n");
190 		return EFI_LOAD_ERROR;
191 	}
192 
193 	/* Link to it in the efi tables */
194 	ret = efi_install_configuration_table(&efi_guid_fdt, fdt);
195 	if (ret != EFI_SUCCESS)
196 		return EFI_OUT_OF_RESOURCES;
197 
198 	return ret;
199 }
200 
201 static efi_status_t bootefi_run_prepare(const char *load_options_path,
202 		struct efi_device_path *device_path,
203 		struct efi_device_path *image_path,
204 		struct efi_loaded_image_obj **image_objp,
205 		struct efi_loaded_image **loaded_image_infop)
206 {
207 	efi_status_t ret;
208 
209 	ret = efi_setup_loaded_image(device_path, image_path, image_objp,
210 				     loaded_image_infop);
211 	if (ret != EFI_SUCCESS)
212 		return ret;
213 
214 	/* Transfer environment variable as load options */
215 	set_load_options(*loaded_image_infop, load_options_path);
216 
217 	return 0;
218 }
219 
220 /**
221  * bootefi_run_finish() - finish up after running an EFI test
222  *
223  * @loaded_image_info: Pointer to a struct which holds the loaded image info
224  * @image_objj: Pointer to a struct which holds the loaded image object
225  */
226 static void bootefi_run_finish(struct efi_loaded_image_obj *image_obj,
227 			       struct efi_loaded_image *loaded_image_info)
228 {
229 	efi_restore_gd();
230 	free(loaded_image_info->load_options);
231 	efi_delete_handle(&image_obj->header);
232 }
233 
234 /**
235  * do_bootefi_exec() - execute EFI binary
236  *
237  * @efi:		address of the binary
238  * @device_path:	path of the device from which the binary was loaded
239  * @image_path:		device path of the binary
240  * Return:		status code
241  *
242  * Load the EFI binary into a newly assigned memory unwinding the relocation
243  * information, install the loaded image protocol, and call the binary.
244  */
245 static efi_status_t do_bootefi_exec(void *efi,
246 				    struct efi_device_path *device_path,
247 				    struct efi_device_path *image_path)
248 {
249 	efi_handle_t mem_handle = NULL;
250 	struct efi_device_path *memdp = NULL;
251 	efi_status_t ret;
252 	struct efi_loaded_image_obj *image_obj = NULL;
253 	struct efi_loaded_image *loaded_image_info = NULL;
254 
255 	/*
256 	 * Special case for efi payload not loaded from disk, such as
257 	 * 'bootefi hello' or for example payload loaded directly into
258 	 * memory via JTAG, etc:
259 	 */
260 	if (!device_path && !image_path) {
261 		printf("WARNING: using memory device/image path, this may confuse some payloads!\n");
262 		/* actual addresses filled in after efi_load_pe() */
263 		memdp = efi_dp_from_mem(EFI_RESERVED_MEMORY_TYPE, 0, 0);
264 		device_path = image_path = memdp;
265 		/*
266 		 * Grub expects that the device path of the loaded image is
267 		 * installed on a handle.
268 		 */
269 		ret = efi_create_handle(&mem_handle);
270 		if (ret != EFI_SUCCESS)
271 			return ret; /* TODO: leaks device_path */
272 		ret = efi_add_protocol(mem_handle, &efi_guid_device_path,
273 				       device_path);
274 		if (ret != EFI_SUCCESS)
275 			goto err_add_protocol;
276 	} else {
277 		assert(device_path && image_path);
278 	}
279 
280 	ret = bootefi_run_prepare("bootargs", device_path, image_path,
281 				  &image_obj, &loaded_image_info);
282 	if (ret)
283 		goto err_prepare;
284 
285 	/* Load the EFI payload */
286 	ret = efi_load_pe(image_obj, efi, loaded_image_info);
287 	if (ret != EFI_SUCCESS)
288 		goto err_prepare;
289 
290 	if (memdp) {
291 		struct efi_device_path_memory *mdp = (void *)memdp;
292 		mdp->memory_type = loaded_image_info->image_code_type;
293 		mdp->start_address = (uintptr_t)loaded_image_info->image_base;
294 		mdp->end_address = mdp->start_address +
295 				loaded_image_info->image_size;
296 	}
297 
298 	/* we don't support much: */
299 	env_set("efi_8be4df61-93ca-11d2-aa0d-00e098032b8c_OsIndicationsSupported",
300 		"{ro,boot}(blob)0000000000000000");
301 
302 	/* Call our payload! */
303 	debug("%s: Jumping to 0x%p\n", __func__, image_obj->entry);
304 	ret = EFI_CALL(efi_start_image(&image_obj->header, NULL, NULL));
305 
306 err_prepare:
307 	/* image has returned, loaded-image obj goes *poof*: */
308 	bootefi_run_finish(image_obj, loaded_image_info);
309 
310 err_add_protocol:
311 	if (mem_handle)
312 		efi_delete_handle(mem_handle);
313 
314 	return ret;
315 }
316 
317 #ifdef CONFIG_CMD_BOOTEFI_SELFTEST
318 /**
319  * bootefi_test_prepare() - prepare to run an EFI test
320  *
321  * Prepare to run a test as if it were provided by a loaded image.
322  *
323  * @image_objp:		pointer to be set to the loaded image handle
324  * @loaded_image_infop:	pointer to be set to the loaded image protocol
325  * @path:		dummy file path used to construct the device path
326  *			set in the loaded image protocol
327  * @load_options_path:	name of a U-Boot environment variable. Its value is
328  *			set as load options in the loaded image protocol.
329  * Return:		status code
330  */
331 static efi_status_t bootefi_test_prepare
332 		(struct efi_loaded_image_obj **image_objp,
333 		 struct efi_loaded_image **loaded_image_infop, const char *path,
334 		 const char *load_options_path)
335 {
336 	efi_status_t ret;
337 
338 	/* Construct a dummy device path */
339 	bootefi_device_path = efi_dp_from_mem(EFI_RESERVED_MEMORY_TYPE, 0, 0);
340 	if (!bootefi_device_path)
341 		return EFI_OUT_OF_RESOURCES;
342 
343 	bootefi_image_path = efi_dp_from_file(NULL, 0, path);
344 	if (!bootefi_image_path) {
345 		ret = EFI_OUT_OF_RESOURCES;
346 		goto failure;
347 	}
348 
349 	ret = bootefi_run_prepare(load_options_path, bootefi_device_path,
350 				  bootefi_image_path, image_objp,
351 				  loaded_image_infop);
352 	if (ret == EFI_SUCCESS)
353 		return ret;
354 
355 	efi_free_pool(bootefi_image_path);
356 	bootefi_image_path = NULL;
357 failure:
358 	efi_free_pool(bootefi_device_path);
359 	bootefi_device_path = NULL;
360 	return ret;
361 }
362 
363 #endif /* CONFIG_CMD_BOOTEFI_SELFTEST */
364 
365 static int do_bootefi_bootmgr_exec(void)
366 {
367 	struct efi_device_path *device_path, *file_path;
368 	void *addr;
369 	efi_status_t r;
370 
371 	addr = efi_bootmgr_load(&device_path, &file_path);
372 	if (!addr)
373 		return 1;
374 
375 	printf("## Starting EFI application at %p ...\n", addr);
376 	r = do_bootefi_exec(addr, device_path, file_path);
377 	printf("## Application terminated, r = %lu\n",
378 	       r & ~EFI_ERROR_MASK);
379 
380 	if (r != EFI_SUCCESS)
381 		return 1;
382 
383 	return 0;
384 }
385 
386 /* Interpreter command to boot an arbitrary EFI image from memory */
387 static int do_bootefi(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
388 {
389 	unsigned long addr;
390 	char *saddr;
391 	efi_status_t r;
392 	unsigned long fdt_addr;
393 
394 	/* Allow unaligned memory access */
395 	allow_unaligned();
396 
397 	switch_to_non_secure_mode();
398 
399 	/* Initialize EFI drivers */
400 	r = efi_init_obj_list();
401 	if (r != EFI_SUCCESS) {
402 		printf("Error: Cannot set up EFI drivers, r = %lu\n",
403 		       r & ~EFI_ERROR_MASK);
404 		return CMD_RET_FAILURE;
405 	}
406 
407 	if (argc < 2)
408 		return CMD_RET_USAGE;
409 
410 	if (argc > 2) {
411 		fdt_addr = simple_strtoul(argv[2], NULL, 16);
412 		if (!fdt_addr && *argv[2] != '0')
413 			return CMD_RET_USAGE;
414 		/* Install device tree */
415 		r = efi_install_fdt(fdt_addr);
416 		if (r != EFI_SUCCESS) {
417 			printf("ERROR: failed to install device tree\n");
418 			return CMD_RET_FAILURE;
419 		}
420 	} else {
421 		/* Remove device tree. EFI_NOT_FOUND can be ignored here */
422 		efi_install_configuration_table(&efi_guid_fdt, NULL);
423 		printf("WARNING: booting without device tree\n");
424 	}
425 #ifdef CONFIG_CMD_BOOTEFI_HELLO
426 	if (!strcmp(argv[1], "hello")) {
427 		ulong size = __efi_helloworld_end - __efi_helloworld_begin;
428 
429 		saddr = env_get("loadaddr");
430 		if (saddr)
431 			addr = simple_strtoul(saddr, NULL, 16);
432 		else
433 			addr = CONFIG_SYS_LOAD_ADDR;
434 		memcpy(map_sysmem(addr, size), __efi_helloworld_begin, size);
435 	} else
436 #endif
437 #ifdef CONFIG_CMD_BOOTEFI_SELFTEST
438 	if (!strcmp(argv[1], "selftest")) {
439 		struct efi_loaded_image_obj *image_obj;
440 		struct efi_loaded_image *loaded_image_info;
441 
442 		r = bootefi_test_prepare(&image_obj, &loaded_image_info,
443 					 "\\selftest", "efi_selftest");
444 		if (r != EFI_SUCCESS)
445 			return CMD_RET_FAILURE;
446 
447 		/* Execute the test */
448 		r = EFI_CALL(efi_selftest(&image_obj->header, &systab));
449 		bootefi_run_finish(image_obj, loaded_image_info);
450 		return r != EFI_SUCCESS;
451 	} else
452 #endif
453 	if (!strcmp(argv[1], "bootmgr")) {
454 		return do_bootefi_bootmgr_exec();
455 	} else {
456 		saddr = argv[1];
457 
458 		addr = simple_strtoul(saddr, NULL, 16);
459 		/* Check that a numeric value was passed */
460 		if (!addr && *saddr != '0')
461 			return CMD_RET_USAGE;
462 
463 	}
464 
465 	printf("## Starting EFI application at %08lx ...\n", addr);
466 	r = do_bootefi_exec(map_sysmem(addr, 0), bootefi_device_path,
467 			    bootefi_image_path);
468 	printf("## Application terminated, r = %lu\n",
469 	       r & ~EFI_ERROR_MASK);
470 
471 	if (r != EFI_SUCCESS)
472 		return 1;
473 	else
474 		return 0;
475 }
476 
477 #ifdef CONFIG_SYS_LONGHELP
478 static char bootefi_help_text[] =
479 	"<image address> [fdt address]\n"
480 	"  - boot EFI payload stored at address <image address>.\n"
481 	"    If specified, the device tree located at <fdt address> gets\n"
482 	"    exposed as EFI configuration table.\n"
483 #ifdef CONFIG_CMD_BOOTEFI_HELLO
484 	"bootefi hello\n"
485 	"  - boot a sample Hello World application stored within U-Boot\n"
486 #endif
487 #ifdef CONFIG_CMD_BOOTEFI_SELFTEST
488 	"bootefi selftest [fdt address]\n"
489 	"  - boot an EFI selftest application stored within U-Boot\n"
490 	"    Use environment variable efi_selftest to select a single test.\n"
491 	"    Use 'setenv efi_selftest list' to enumerate all tests.\n"
492 #endif
493 	"bootefi bootmgr [fdt addr]\n"
494 	"  - load and boot EFI payload based on BootOrder/BootXXXX variables.\n"
495 	"\n"
496 	"    If specified, the device tree located at <fdt address> gets\n"
497 	"    exposed as EFI configuration table.\n";
498 #endif
499 
500 U_BOOT_CMD(
501 	bootefi, 3, 0, do_bootefi,
502 	"Boots an EFI payload from memory",
503 	bootefi_help_text
504 );
505 
506 void efi_set_bootdev(const char *dev, const char *devnr, const char *path)
507 {
508 	struct efi_device_path *device, *image;
509 	efi_status_t ret;
510 
511 	/* efi_set_bootdev is typically called repeatedly, recover memory */
512 	efi_free_pool(bootefi_device_path);
513 	efi_free_pool(bootefi_image_path);
514 
515 	ret = efi_dp_from_name(dev, devnr, path, &device, &image);
516 	if (ret == EFI_SUCCESS) {
517 		bootefi_device_path = device;
518 		bootefi_image_path = image;
519 	} else {
520 		bootefi_device_path = NULL;
521 		bootefi_image_path = NULL;
522 	}
523 }
524