xref: /openbmc/u-boot/cmd/bootefi.c (revision e9c847c3)
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/device.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 /*
24  * When booting using the "bootefi" command, we don't know which
25  * physical device the file came from. So we create a pseudo-device
26  * called "bootefi" with the device path /bootefi.
27  *
28  * In addition to the originating device we also declare the file path
29  * of "bootefi" based loads to be /bootefi.
30  */
31 static struct efi_device_path_file_path bootefi_image_path[] = {
32 	{
33 		.dp.type = DEVICE_PATH_TYPE_MEDIA_DEVICE,
34 		.dp.sub_type = DEVICE_PATH_SUB_TYPE_FILE_PATH,
35 		.dp.length = sizeof(bootefi_image_path[0]),
36 		.str = { 'b','o','o','t','e','f','i' },
37 	}, {
38 		.dp.type = DEVICE_PATH_TYPE_END,
39 		.dp.sub_type = DEVICE_PATH_SUB_TYPE_END,
40 		.dp.length = sizeof(bootefi_image_path[0]),
41 	}
42 };
43 
44 static struct efi_device_path_file_path bootefi_device_path[] = {
45 	{
46 		.dp.type = DEVICE_PATH_TYPE_MEDIA_DEVICE,
47 		.dp.sub_type = DEVICE_PATH_SUB_TYPE_FILE_PATH,
48 		.dp.length = sizeof(bootefi_image_path[0]),
49 		.str = { 'b','o','o','t','e','f','i' },
50 	}, {
51 		.dp.type = DEVICE_PATH_TYPE_END,
52 		.dp.sub_type = DEVICE_PATH_SUB_TYPE_END,
53 		.dp.length = sizeof(bootefi_image_path[0]),
54 	}
55 };
56 
57 static efi_status_t EFIAPI bootefi_open_dp(void *handle, efi_guid_t *protocol,
58 			void **protocol_interface, void *agent_handle,
59 			void *controller_handle, uint32_t attributes)
60 {
61 	*protocol_interface = bootefi_device_path;
62 	return EFI_SUCCESS;
63 }
64 
65 /* The EFI loaded_image interface for the image executed via "bootefi" */
66 static struct efi_loaded_image loaded_image_info = {
67 	.device_handle = bootefi_device_path,
68 	.file_path = bootefi_image_path,
69 };
70 
71 /* The EFI object struct for the image executed via "bootefi" */
72 static struct efi_object loaded_image_info_obj = {
73 	.handle = &loaded_image_info,
74 	.protocols = {
75 		{
76 			/*
77 			 * When asking for the loaded_image interface, just
78 			 * return handle which points to loaded_image_info
79 			 */
80 			.guid = &efi_guid_loaded_image,
81 			.open = &efi_return_handle,
82 		},
83 		{
84 			/*
85 			 * When asking for the device path interface, return
86 			 * bootefi_device_path
87 			 */
88 			.guid = &efi_guid_device_path,
89 			.open = &bootefi_open_dp,
90 		},
91 	},
92 };
93 
94 /* The EFI object struct for the device the "bootefi" image was loaded from */
95 static struct efi_object bootefi_device_obj = {
96 	.handle = bootefi_device_path,
97 	.protocols = {
98 		{
99 			/* When asking for the device path interface, return
100 			 * bootefi_device_path */
101 			.guid = &efi_guid_device_path,
102 			.open = &bootefi_open_dp,
103 		}
104 	},
105 };
106 
107 static void *copy_fdt(void *fdt)
108 {
109 	u64 fdt_size = fdt_totalsize(fdt);
110 	unsigned long fdt_ram_start = -1L, fdt_pages;
111 	u64 new_fdt_addr;
112 	void *new_fdt;
113 	int i;
114 
115         for (i = 0; i < CONFIG_NR_DRAM_BANKS; i++) {
116                 u64 ram_start = gd->bd->bi_dram[i].start;
117                 u64 ram_size = gd->bd->bi_dram[i].size;
118 
119 		if (!ram_size)
120 			continue;
121 
122 		if (ram_start < fdt_ram_start)
123 			fdt_ram_start = ram_start;
124 	}
125 
126 	/* Give us at least 4kb breathing room */
127 	fdt_size = ALIGN(fdt_size + 4096, 4096);
128 	fdt_pages = fdt_size >> EFI_PAGE_SHIFT;
129 
130 	/* Safe fdt location is at 128MB */
131 	new_fdt_addr = fdt_ram_start + (128 * 1024 * 1024) + fdt_size;
132 	if (efi_allocate_pages(1, EFI_BOOT_SERVICES_DATA, fdt_pages,
133 			       &new_fdt_addr) != EFI_SUCCESS) {
134 		/* If we can't put it there, put it somewhere */
135 		new_fdt_addr = (ulong)memalign(4096, fdt_size);
136 	}
137 	new_fdt = (void*)(ulong)new_fdt_addr;
138 	memcpy(new_fdt, fdt, fdt_totalsize(fdt));
139 	fdt_set_totalsize(new_fdt, fdt_size);
140 
141 	return new_fdt;
142 }
143 
144 #ifdef CONFIG_ARM64
145 static unsigned long efi_run_in_el2(ulong (*entry)(void *image_handle,
146 		struct efi_system_table *st), void *image_handle,
147 		struct efi_system_table *st)
148 {
149 	/* Enable caches again */
150 	dcache_enable();
151 
152 	return entry(image_handle, st);
153 }
154 #endif
155 
156 /*
157  * Load an EFI payload into a newly allocated piece of memory, register all
158  * EFI objects it would want to access and jump to it.
159  */
160 static unsigned long do_bootefi_exec(void *efi, void *fdt)
161 {
162 	ulong (*entry)(void *image_handle, struct efi_system_table *st)
163 		asmlinkage;
164 	ulong fdt_pages, fdt_size, fdt_start, fdt_end;
165 	bootm_headers_t img = { 0 };
166 
167 	/*
168 	 * gd lives in a fixed register which may get clobbered while we execute
169 	 * the payload. So save it here and restore it on every callback entry
170 	 */
171 	efi_save_gd();
172 
173 	if (fdt && !fdt_check_header(fdt)) {
174 		/* Prepare fdt for payload */
175 		fdt = copy_fdt(fdt);
176 
177 		if (image_setup_libfdt(&img, fdt, 0, NULL)) {
178 			printf("ERROR: Failed to process device tree\n");
179 			return -EINVAL;
180 		}
181 
182 		/* Link to it in the efi tables */
183 		systab.tables[0].guid = EFI_FDT_GUID;
184 		systab.tables[0].table = fdt;
185 		systab.nr_tables = 1;
186 
187 		/* And reserve the space in the memory map */
188 		fdt_start = ((ulong)fdt) & ~EFI_PAGE_MASK;
189 		fdt_end = ((ulong)fdt) + fdt_totalsize(fdt);
190 		fdt_size = (fdt_end - fdt_start) + EFI_PAGE_MASK;
191 		fdt_pages = fdt_size >> EFI_PAGE_SHIFT;
192 		/* Give a bootloader the chance to modify the device tree */
193 		fdt_pages += 2;
194 		efi_add_memory_map(fdt_start, fdt_pages,
195 				   EFI_BOOT_SERVICES_DATA, true);
196 	} else {
197 		printf("WARNING: Invalid device tree, expect boot to fail\n");
198 		systab.nr_tables = 0;
199 	}
200 
201 	/* Load the EFI payload */
202 	entry = efi_load_pe(efi, &loaded_image_info);
203 	if (!entry)
204 		return -ENOENT;
205 
206 	/* Initialize and populate EFI object list */
207 	INIT_LIST_HEAD(&efi_obj_list);
208 	list_add_tail(&loaded_image_info_obj.link, &efi_obj_list);
209 	list_add_tail(&bootefi_device_obj.link, &efi_obj_list);
210 #ifdef CONFIG_PARTITIONS
211 	efi_disk_register();
212 #endif
213 #ifdef CONFIG_LCD
214 	efi_gop_register();
215 #endif
216 #ifdef CONFIG_NET
217 	void *nethandle = loaded_image_info.device_handle;
218 	efi_net_register(&nethandle);
219 
220 	if (!memcmp(bootefi_device_path[0].str, "N\0e\0t", 6))
221 		loaded_image_info.device_handle = nethandle;
222 	else
223 		loaded_image_info.device_handle = bootefi_device_path;
224 #endif
225 #ifdef CONFIG_GENERATE_SMBIOS_TABLE
226 	efi_smbios_register();
227 #endif
228 
229 	/* Initialize EFI runtime services */
230 	efi_reset_system_init();
231 	efi_get_time_init();
232 
233 	/* Call our payload! */
234 	debug("%s:%d Jumping to 0x%lx\n", __func__, __LINE__, (long)entry);
235 
236 	if (setjmp(&loaded_image_info.exit_jmp)) {
237 		efi_status_t status = loaded_image_info.exit_status;
238 		return status == EFI_SUCCESS ? 0 : -EINVAL;
239 	}
240 
241 #ifdef CONFIG_ARM64
242 	/* On AArch64 we need to make sure we call our payload in < EL3 */
243 	if (current_el() == 3) {
244 		smp_kick_all_cpus();
245 		dcache_disable();	/* flush cache before switch to EL2 */
246 
247 		/* Move into EL2 and keep running there */
248 		armv8_switch_to_el2((ulong)entry, (ulong)&loaded_image_info,
249 				    (ulong)&systab, (ulong)efi_run_in_el2,
250 				    ES_TO_AARCH64);
251 
252 		/* Should never reach here, efi exits with longjmp */
253 		while (1) { }
254 	}
255 #endif
256 
257 	return entry(&loaded_image_info, &systab);
258 }
259 
260 
261 /* Interpreter command to boot an arbitrary EFI image from memory */
262 static int do_bootefi(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
263 {
264 	char *saddr, *sfdt;
265 	unsigned long addr, fdt_addr = 0;
266 	int r = 0;
267 
268 	if (argc < 2)
269 		return CMD_RET_USAGE;
270 #ifdef CONFIG_CMD_BOOTEFI_HELLO
271 	if (!strcmp(argv[1], "hello")) {
272 		ulong size = __efi_hello_world_end - __efi_hello_world_begin;
273 
274 		addr = CONFIG_SYS_LOAD_ADDR;
275 		memcpy((char *)addr, __efi_hello_world_begin, size);
276 	} else
277 #endif
278 	{
279 		saddr = argv[1];
280 
281 		addr = simple_strtoul(saddr, NULL, 16);
282 
283 		if (argc > 2) {
284 			sfdt = argv[2];
285 			fdt_addr = simple_strtoul(sfdt, NULL, 16);
286 		}
287 	}
288 
289 	printf("## Starting EFI application at %08lx ...\n", addr);
290 	r = do_bootefi_exec((void *)addr, (void*)fdt_addr);
291 	printf("## Application terminated, r = %d\n", r);
292 
293 	if (r != 0)
294 		r = 1;
295 
296 	return r;
297 }
298 
299 #ifdef CONFIG_SYS_LONGHELP
300 static char bootefi_help_text[] =
301 	"<image address> [fdt address]\n"
302 	"  - boot EFI payload stored at address <image address>.\n"
303 	"    If specified, the device tree located at <fdt address> gets\n"
304 	"    exposed as EFI configuration table.\n"
305 #ifdef CONFIG_CMD_BOOTEFI_HELLO
306 	"hello\n"
307 	"  - boot a sample Hello World application stored within U-Boot"
308 #endif
309 	;
310 #endif
311 
312 U_BOOT_CMD(
313 	bootefi, 3, 0, do_bootefi,
314 	"Boots an EFI payload from memory",
315 	bootefi_help_text
316 );
317 
318 void efi_set_bootdev(const char *dev, const char *devnr, const char *path)
319 {
320 	__maybe_unused struct blk_desc *desc;
321 	char devname[32] = { 0 }; /* dp->str is u16[32] long */
322 	char *colon;
323 
324 #if defined(CONFIG_BLK) || defined(CONFIG_ISO_PARTITION)
325 	desc = blk_get_dev(dev, simple_strtol(devnr, NULL, 10));
326 #endif
327 
328 #ifdef CONFIG_BLK
329 	if (desc) {
330 		snprintf(devname, sizeof(devname), "%s", desc->bdev->name);
331 	} else
332 #endif
333 
334 	{
335 		/* Assemble the condensed device name we use in efi_disk.c */
336 		snprintf(devname, sizeof(devname), "%s%s", dev, devnr);
337 	}
338 
339 	colon = strchr(devname, ':');
340 
341 #ifdef CONFIG_ISO_PARTITION
342 	/* For ISOs we create partition block devices */
343 	if (desc && (desc->type != DEV_TYPE_UNKNOWN) &&
344 	    (desc->part_type == PART_TYPE_ISO)) {
345 		if (!colon)
346 			snprintf(devname, sizeof(devname), "%s:1", devname);
347 
348 		colon = NULL;
349 	}
350 #endif
351 
352 	if (colon)
353 		*colon = '\0';
354 
355 	/* Patch bootefi_device_path to the target device */
356 	memset(bootefi_device_path[0].str, 0, sizeof(bootefi_device_path[0].str));
357 	ascii2unicode(bootefi_device_path[0].str, devname);
358 
359 	/* Patch bootefi_image_path to the target file path */
360 	memset(bootefi_image_path[0].str, 0, sizeof(bootefi_image_path[0].str));
361 	if (strcmp(dev, "Net")) {
362 		/* Add leading / to fs paths, because they're absolute */
363 		snprintf(devname, sizeof(devname), "/%s", path);
364 	} else {
365 		snprintf(devname, sizeof(devname), "%s", path);
366 	}
367 	ascii2unicode(bootefi_image_path[0].str, devname);
368 }
369