1 /* -----------------------------------------------------------------------
2  *
3  *   Copyright 2011 Intel Corporation; author Matt Fleming
4  *
5  *   This file is part of the Linux kernel, and is made available under
6  *   the terms of the GNU General Public License version 2.
7  *
8  * ----------------------------------------------------------------------- */
9 
10 #include <linux/efi.h>
11 #include <linux/pci.h>
12 
13 #include <asm/efi.h>
14 #include <asm/e820/types.h>
15 #include <asm/setup.h>
16 #include <asm/desc.h>
17 
18 #include "../string.h"
19 #include "eboot.h"
20 
21 static efi_system_table_t *sys_table;
22 
23 static struct efi_config *efi_early;
24 
__efi_early(void)25 __pure const struct efi_config *__efi_early(void)
26 {
27 	return efi_early;
28 }
29 
30 #define BOOT_SERVICES(bits)						\
31 static void setup_boot_services##bits(struct efi_config *c)		\
32 {									\
33 	efi_system_table_##bits##_t *table;				\
34 									\
35 	table = (typeof(table))sys_table;				\
36 									\
37 	c->runtime_services	= table->runtime;			\
38 	c->boot_services	= table->boottime;			\
39 	c->text_output		= table->con_out;			\
40 }
41 BOOT_SERVICES(32);
42 BOOT_SERVICES(64);
43 
efi_char16_printk(efi_system_table_t * table,efi_char16_t * str)44 void efi_char16_printk(efi_system_table_t *table, efi_char16_t *str)
45 {
46 	efi_call_proto(efi_simple_text_output_protocol, output_string,
47 		       efi_early->text_output, str);
48 }
49 
50 static efi_status_t
preserve_pci_rom_image(efi_pci_io_protocol_t * pci,struct pci_setup_rom ** __rom)51 preserve_pci_rom_image(efi_pci_io_protocol_t *pci, struct pci_setup_rom **__rom)
52 {
53 	struct pci_setup_rom *rom = NULL;
54 	efi_status_t status;
55 	unsigned long size;
56 	uint64_t romsize;
57 	void *romimage;
58 
59 	/*
60 	 * Some firmware images contain EFI function pointers at the place where
61 	 * the romimage and romsize fields are supposed to be. Typically the EFI
62 	 * code is mapped at high addresses, translating to an unrealistically
63 	 * large romsize. The UEFI spec limits the size of option ROMs to 16
64 	 * MiB so we reject any ROMs over 16 MiB in size to catch this.
65 	 */
66 	romimage = (void *)(unsigned long)efi_table_attr(efi_pci_io_protocol,
67 							 romimage, pci);
68 	romsize = efi_table_attr(efi_pci_io_protocol, romsize, pci);
69 	if (!romimage || !romsize || romsize > SZ_16M)
70 		return EFI_INVALID_PARAMETER;
71 
72 	size = romsize + sizeof(*rom);
73 
74 	status = efi_call_early(allocate_pool, EFI_LOADER_DATA, size, &rom);
75 	if (status != EFI_SUCCESS) {
76 		efi_printk(sys_table, "Failed to allocate memory for 'rom'\n");
77 		return status;
78 	}
79 
80 	memset(rom, 0, sizeof(*rom));
81 
82 	rom->data.type	= SETUP_PCI;
83 	rom->data.len	= size - sizeof(struct setup_data);
84 	rom->data.next	= 0;
85 	rom->pcilen	= pci->romsize;
86 	*__rom = rom;
87 
88 	status = efi_call_proto(efi_pci_io_protocol, pci.read, pci,
89 				EfiPciIoWidthUint16, PCI_VENDOR_ID, 1,
90 				&rom->vendor);
91 
92 	if (status != EFI_SUCCESS) {
93 		efi_printk(sys_table, "Failed to read rom->vendor\n");
94 		goto free_struct;
95 	}
96 
97 	status = efi_call_proto(efi_pci_io_protocol, pci.read, pci,
98 				EfiPciIoWidthUint16, PCI_DEVICE_ID, 1,
99 				&rom->devid);
100 
101 	if (status != EFI_SUCCESS) {
102 		efi_printk(sys_table, "Failed to read rom->devid\n");
103 		goto free_struct;
104 	}
105 
106 	status = efi_call_proto(efi_pci_io_protocol, get_location, pci,
107 				&rom->segment, &rom->bus, &rom->device,
108 				&rom->function);
109 
110 	if (status != EFI_SUCCESS)
111 		goto free_struct;
112 
113 	memcpy(rom->romdata, romimage, romsize);
114 	return status;
115 
116 free_struct:
117 	efi_call_early(free_pool, rom);
118 	return status;
119 }
120 
121 /*
122  * There's no way to return an informative status from this function,
123  * because any analysis (and printing of error messages) needs to be
124  * done directly at the EFI function call-site.
125  *
126  * For example, EFI_INVALID_PARAMETER could indicate a bug or maybe we
127  * just didn't find any PCI devices, but there's no way to tell outside
128  * the context of the call.
129  */
setup_efi_pci(struct boot_params * params)130 static void setup_efi_pci(struct boot_params *params)
131 {
132 	efi_status_t status;
133 	void **pci_handle = NULL;
134 	efi_guid_t pci_proto = EFI_PCI_IO_PROTOCOL_GUID;
135 	unsigned long size = 0;
136 	unsigned long nr_pci;
137 	struct setup_data *data;
138 	int i;
139 
140 	status = efi_call_early(locate_handle,
141 				EFI_LOCATE_BY_PROTOCOL,
142 				&pci_proto, NULL, &size, pci_handle);
143 
144 	if (status == EFI_BUFFER_TOO_SMALL) {
145 		status = efi_call_early(allocate_pool,
146 					EFI_LOADER_DATA,
147 					size, (void **)&pci_handle);
148 
149 		if (status != EFI_SUCCESS) {
150 			efi_printk(sys_table, "Failed to allocate memory for 'pci_handle'\n");
151 			return;
152 		}
153 
154 		status = efi_call_early(locate_handle,
155 					EFI_LOCATE_BY_PROTOCOL, &pci_proto,
156 					NULL, &size, pci_handle);
157 	}
158 
159 	if (status != EFI_SUCCESS)
160 		goto free_handle;
161 
162 	data = (struct setup_data *)(unsigned long)params->hdr.setup_data;
163 
164 	while (data && data->next)
165 		data = (struct setup_data *)(unsigned long)data->next;
166 
167 	nr_pci = size / (efi_is_64bit() ? sizeof(u64) : sizeof(u32));
168 	for (i = 0; i < nr_pci; i++) {
169 		efi_pci_io_protocol_t *pci = NULL;
170 		struct pci_setup_rom *rom;
171 
172 		status = efi_call_early(handle_protocol,
173 					efi_is_64bit() ? ((u64 *)pci_handle)[i]
174 						       : ((u32 *)pci_handle)[i],
175 					&pci_proto, (void **)&pci);
176 		if (status != EFI_SUCCESS || !pci)
177 			continue;
178 
179 		status = preserve_pci_rom_image(pci, &rom);
180 		if (status != EFI_SUCCESS)
181 			continue;
182 
183 		if (data)
184 			data->next = (unsigned long)rom;
185 		else
186 			params->hdr.setup_data = (unsigned long)rom;
187 
188 		data = (struct setup_data *)rom;
189 	}
190 
191 free_handle:
192 	efi_call_early(free_pool, pci_handle);
193 }
194 
retrieve_apple_device_properties(struct boot_params * boot_params)195 static void retrieve_apple_device_properties(struct boot_params *boot_params)
196 {
197 	efi_guid_t guid = APPLE_PROPERTIES_PROTOCOL_GUID;
198 	struct setup_data *data, *new;
199 	efi_status_t status;
200 	u32 size = 0;
201 	void *p;
202 
203 	status = efi_call_early(locate_protocol, &guid, NULL, &p);
204 	if (status != EFI_SUCCESS)
205 		return;
206 
207 	if (efi_table_attr(apple_properties_protocol, version, p) != 0x10000) {
208 		efi_printk(sys_table, "Unsupported properties proto version\n");
209 		return;
210 	}
211 
212 	efi_call_proto(apple_properties_protocol, get_all, p, NULL, &size);
213 	if (!size)
214 		return;
215 
216 	do {
217 		status = efi_call_early(allocate_pool, EFI_LOADER_DATA,
218 					size + sizeof(struct setup_data), &new);
219 		if (status != EFI_SUCCESS) {
220 			efi_printk(sys_table, "Failed to allocate memory for 'properties'\n");
221 			return;
222 		}
223 
224 		status = efi_call_proto(apple_properties_protocol, get_all, p,
225 					new->data, &size);
226 
227 		if (status == EFI_BUFFER_TOO_SMALL)
228 			efi_call_early(free_pool, new);
229 	} while (status == EFI_BUFFER_TOO_SMALL);
230 
231 	new->type = SETUP_APPLE_PROPERTIES;
232 	new->len  = size;
233 	new->next = 0;
234 
235 	data = (struct setup_data *)(unsigned long)boot_params->hdr.setup_data;
236 	if (!data) {
237 		boot_params->hdr.setup_data = (unsigned long)new;
238 	} else {
239 		while (data->next)
240 			data = (struct setup_data *)(unsigned long)data->next;
241 		data->next = (unsigned long)new;
242 	}
243 }
244 
245 static const efi_char16_t apple[] = L"Apple";
246 
setup_quirks(struct boot_params * boot_params)247 static void setup_quirks(struct boot_params *boot_params)
248 {
249 	efi_char16_t *fw_vendor = (efi_char16_t *)(unsigned long)
250 		efi_table_attr(efi_system_table, fw_vendor, sys_table);
251 
252 	if (!memcmp(fw_vendor, apple, sizeof(apple))) {
253 		if (IS_ENABLED(CONFIG_APPLE_PROPERTIES))
254 			retrieve_apple_device_properties(boot_params);
255 	}
256 }
257 
258 /*
259  * See if we have Universal Graphics Adapter (UGA) protocol
260  */
261 static efi_status_t
setup_uga(struct screen_info * si,efi_guid_t * uga_proto,unsigned long size)262 setup_uga(struct screen_info *si, efi_guid_t *uga_proto, unsigned long size)
263 {
264 	efi_status_t status;
265 	u32 width, height;
266 	void **uga_handle = NULL;
267 	efi_uga_draw_protocol_t *uga = NULL, *first_uga;
268 	unsigned long nr_ugas;
269 	int i;
270 
271 	status = efi_call_early(allocate_pool, EFI_LOADER_DATA,
272 				size, (void **)&uga_handle);
273 	if (status != EFI_SUCCESS)
274 		return status;
275 
276 	status = efi_call_early(locate_handle,
277 				EFI_LOCATE_BY_PROTOCOL,
278 				uga_proto, NULL, &size, uga_handle);
279 	if (status != EFI_SUCCESS)
280 		goto free_handle;
281 
282 	height = 0;
283 	width = 0;
284 
285 	first_uga = NULL;
286 	nr_ugas = size / (efi_is_64bit() ? sizeof(u64) : sizeof(u32));
287 	for (i = 0; i < nr_ugas; i++) {
288 		efi_guid_t pciio_proto = EFI_PCI_IO_PROTOCOL_GUID;
289 		u32 w, h, depth, refresh;
290 		void *pciio;
291 		unsigned long handle = efi_is_64bit() ? ((u64 *)uga_handle)[i]
292 						      : ((u32 *)uga_handle)[i];
293 
294 		status = efi_call_early(handle_protocol, handle,
295 					uga_proto, (void **)&uga);
296 		if (status != EFI_SUCCESS)
297 			continue;
298 
299 		pciio = NULL;
300 		efi_call_early(handle_protocol, handle, &pciio_proto, &pciio);
301 
302 		status = efi_call_proto(efi_uga_draw_protocol, get_mode, uga,
303 					&w, &h, &depth, &refresh);
304 		if (status == EFI_SUCCESS && (!first_uga || pciio)) {
305 			width = w;
306 			height = h;
307 
308 			/*
309 			 * Once we've found a UGA supporting PCIIO,
310 			 * don't bother looking any further.
311 			 */
312 			if (pciio)
313 				break;
314 
315 			first_uga = uga;
316 		}
317 	}
318 
319 	if (!width && !height)
320 		goto free_handle;
321 
322 	/* EFI framebuffer */
323 	si->orig_video_isVGA	= VIDEO_TYPE_EFI;
324 
325 	si->lfb_depth		= 32;
326 	si->lfb_width		= width;
327 	si->lfb_height		= height;
328 
329 	si->red_size		= 8;
330 	si->red_pos		= 16;
331 	si->green_size		= 8;
332 	si->green_pos		= 8;
333 	si->blue_size		= 8;
334 	si->blue_pos		= 0;
335 	si->rsvd_size		= 8;
336 	si->rsvd_pos		= 24;
337 
338 free_handle:
339 	efi_call_early(free_pool, uga_handle);
340 
341 	return status;
342 }
343 
setup_graphics(struct boot_params * boot_params)344 void setup_graphics(struct boot_params *boot_params)
345 {
346 	efi_guid_t graphics_proto = EFI_GRAPHICS_OUTPUT_PROTOCOL_GUID;
347 	struct screen_info *si;
348 	efi_guid_t uga_proto = EFI_UGA_PROTOCOL_GUID;
349 	efi_status_t status;
350 	unsigned long size;
351 	void **gop_handle = NULL;
352 	void **uga_handle = NULL;
353 
354 	si = &boot_params->screen_info;
355 	memset(si, 0, sizeof(*si));
356 
357 	size = 0;
358 	status = efi_call_early(locate_handle,
359 				EFI_LOCATE_BY_PROTOCOL,
360 				&graphics_proto, NULL, &size, gop_handle);
361 	if (status == EFI_BUFFER_TOO_SMALL)
362 		status = efi_setup_gop(NULL, si, &graphics_proto, size);
363 
364 	if (status != EFI_SUCCESS) {
365 		size = 0;
366 		status = efi_call_early(locate_handle,
367 					EFI_LOCATE_BY_PROTOCOL,
368 					&uga_proto, NULL, &size, uga_handle);
369 		if (status == EFI_BUFFER_TOO_SMALL)
370 			setup_uga(si, &uga_proto, size);
371 	}
372 }
373 
374 /*
375  * Because the x86 boot code expects to be passed a boot_params we
376  * need to create one ourselves (usually the bootloader would create
377  * one for us).
378  *
379  * The caller is responsible for filling out ->code32_start in the
380  * returned boot_params.
381  */
make_boot_params(struct efi_config * c)382 struct boot_params *make_boot_params(struct efi_config *c)
383 {
384 	struct boot_params *boot_params;
385 	struct apm_bios_info *bi;
386 	struct setup_header *hdr;
387 	efi_loaded_image_t *image;
388 	void *options, *handle;
389 	efi_guid_t proto = LOADED_IMAGE_PROTOCOL_GUID;
390 	int options_size = 0;
391 	efi_status_t status;
392 	char *cmdline_ptr;
393 	u16 *s2;
394 	u8 *s1;
395 	int i;
396 	unsigned long ramdisk_addr;
397 	unsigned long ramdisk_size;
398 
399 	efi_early = c;
400 	sys_table = (efi_system_table_t *)(unsigned long)efi_early->table;
401 	handle = (void *)(unsigned long)efi_early->image_handle;
402 
403 	/* Check if we were booted by the EFI firmware */
404 	if (sys_table->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE)
405 		return NULL;
406 
407 	if (efi_is_64bit())
408 		setup_boot_services64(efi_early);
409 	else
410 		setup_boot_services32(efi_early);
411 
412 	status = efi_call_early(handle_protocol, handle,
413 				&proto, (void *)&image);
414 	if (status != EFI_SUCCESS) {
415 		efi_printk(sys_table, "Failed to get handle for LOADED_IMAGE_PROTOCOL\n");
416 		return NULL;
417 	}
418 
419 	status = efi_low_alloc(sys_table, 0x4000, 1,
420 			       (unsigned long *)&boot_params);
421 	if (status != EFI_SUCCESS) {
422 		efi_printk(sys_table, "Failed to allocate lowmem for boot params\n");
423 		return NULL;
424 	}
425 
426 	memset(boot_params, 0x0, 0x4000);
427 
428 	hdr = &boot_params->hdr;
429 	bi = &boot_params->apm_bios_info;
430 
431 	/* Copy the second sector to boot_params */
432 	memcpy(&hdr->jump, image->image_base + 512, 512);
433 
434 	/*
435 	 * Fill out some of the header fields ourselves because the
436 	 * EFI firmware loader doesn't load the first sector.
437 	 */
438 	hdr->root_flags	= 1;
439 	hdr->vid_mode	= 0xffff;
440 	hdr->boot_flag	= 0xAA55;
441 
442 	hdr->type_of_loader = 0x21;
443 
444 	/* Convert unicode cmdline to ascii */
445 	cmdline_ptr = efi_convert_cmdline(sys_table, image, &options_size);
446 	if (!cmdline_ptr)
447 		goto fail;
448 
449 	hdr->cmd_line_ptr = (unsigned long)cmdline_ptr;
450 	/* Fill in upper bits of command line address, NOP on 32 bit  */
451 	boot_params->ext_cmd_line_ptr = (u64)(unsigned long)cmdline_ptr >> 32;
452 
453 	hdr->ramdisk_image = 0;
454 	hdr->ramdisk_size = 0;
455 
456 	/* Clear APM BIOS info */
457 	memset(bi, 0, sizeof(*bi));
458 
459 	status = efi_parse_options(cmdline_ptr);
460 	if (status != EFI_SUCCESS)
461 		goto fail2;
462 
463 	status = handle_cmdline_files(sys_table, image,
464 				      (char *)(unsigned long)hdr->cmd_line_ptr,
465 				      "initrd=", hdr->initrd_addr_max,
466 				      &ramdisk_addr, &ramdisk_size);
467 
468 	if (status != EFI_SUCCESS &&
469 	    hdr->xloadflags & XLF_CAN_BE_LOADED_ABOVE_4G) {
470 		efi_printk(sys_table, "Trying to load files to higher address\n");
471 		status = handle_cmdline_files(sys_table, image,
472 				      (char *)(unsigned long)hdr->cmd_line_ptr,
473 				      "initrd=", -1UL,
474 				      &ramdisk_addr, &ramdisk_size);
475 	}
476 
477 	if (status != EFI_SUCCESS)
478 		goto fail2;
479 	hdr->ramdisk_image = ramdisk_addr & 0xffffffff;
480 	hdr->ramdisk_size  = ramdisk_size & 0xffffffff;
481 	boot_params->ext_ramdisk_image = (u64)ramdisk_addr >> 32;
482 	boot_params->ext_ramdisk_size  = (u64)ramdisk_size >> 32;
483 
484 	return boot_params;
485 
486 fail2:
487 	efi_free(sys_table, options_size, hdr->cmd_line_ptr);
488 fail:
489 	efi_free(sys_table, 0x4000, (unsigned long)boot_params);
490 
491 	return NULL;
492 }
493 
add_e820ext(struct boot_params * params,struct setup_data * e820ext,u32 nr_entries)494 static void add_e820ext(struct boot_params *params,
495 			struct setup_data *e820ext, u32 nr_entries)
496 {
497 	struct setup_data *data;
498 	efi_status_t status;
499 	unsigned long size;
500 
501 	e820ext->type = SETUP_E820_EXT;
502 	e820ext->len  = nr_entries * sizeof(struct boot_e820_entry);
503 	e820ext->next = 0;
504 
505 	data = (struct setup_data *)(unsigned long)params->hdr.setup_data;
506 
507 	while (data && data->next)
508 		data = (struct setup_data *)(unsigned long)data->next;
509 
510 	if (data)
511 		data->next = (unsigned long)e820ext;
512 	else
513 		params->hdr.setup_data = (unsigned long)e820ext;
514 }
515 
516 static efi_status_t
setup_e820(struct boot_params * params,struct setup_data * e820ext,u32 e820ext_size)517 setup_e820(struct boot_params *params, struct setup_data *e820ext, u32 e820ext_size)
518 {
519 	struct boot_e820_entry *entry = params->e820_table;
520 	struct efi_info *efi = &params->efi_info;
521 	struct boot_e820_entry *prev = NULL;
522 	u32 nr_entries;
523 	u32 nr_desc;
524 	int i;
525 
526 	nr_entries = 0;
527 	nr_desc = efi->efi_memmap_size / efi->efi_memdesc_size;
528 
529 	for (i = 0; i < nr_desc; i++) {
530 		efi_memory_desc_t *d;
531 		unsigned int e820_type = 0;
532 		unsigned long m = efi->efi_memmap;
533 
534 #ifdef CONFIG_X86_64
535 		m |= (u64)efi->efi_memmap_hi << 32;
536 #endif
537 
538 		d = efi_early_memdesc_ptr(m, efi->efi_memdesc_size, i);
539 		switch (d->type) {
540 		case EFI_RESERVED_TYPE:
541 		case EFI_RUNTIME_SERVICES_CODE:
542 		case EFI_RUNTIME_SERVICES_DATA:
543 		case EFI_MEMORY_MAPPED_IO:
544 		case EFI_MEMORY_MAPPED_IO_PORT_SPACE:
545 		case EFI_PAL_CODE:
546 			e820_type = E820_TYPE_RESERVED;
547 			break;
548 
549 		case EFI_UNUSABLE_MEMORY:
550 			e820_type = E820_TYPE_UNUSABLE;
551 			break;
552 
553 		case EFI_ACPI_RECLAIM_MEMORY:
554 			e820_type = E820_TYPE_ACPI;
555 			break;
556 
557 		case EFI_LOADER_CODE:
558 		case EFI_LOADER_DATA:
559 		case EFI_BOOT_SERVICES_CODE:
560 		case EFI_BOOT_SERVICES_DATA:
561 		case EFI_CONVENTIONAL_MEMORY:
562 			e820_type = E820_TYPE_RAM;
563 			break;
564 
565 		case EFI_ACPI_MEMORY_NVS:
566 			e820_type = E820_TYPE_NVS;
567 			break;
568 
569 		case EFI_PERSISTENT_MEMORY:
570 			e820_type = E820_TYPE_PMEM;
571 			break;
572 
573 		default:
574 			continue;
575 		}
576 
577 		/* Merge adjacent mappings */
578 		if (prev && prev->type == e820_type &&
579 		    (prev->addr + prev->size) == d->phys_addr) {
580 			prev->size += d->num_pages << 12;
581 			continue;
582 		}
583 
584 		if (nr_entries == ARRAY_SIZE(params->e820_table)) {
585 			u32 need = (nr_desc - i) * sizeof(struct e820_entry) +
586 				   sizeof(struct setup_data);
587 
588 			if (!e820ext || e820ext_size < need)
589 				return EFI_BUFFER_TOO_SMALL;
590 
591 			/* boot_params map full, switch to e820 extended */
592 			entry = (struct boot_e820_entry *)e820ext->data;
593 		}
594 
595 		entry->addr = d->phys_addr;
596 		entry->size = d->num_pages << PAGE_SHIFT;
597 		entry->type = e820_type;
598 		prev = entry++;
599 		nr_entries++;
600 	}
601 
602 	if (nr_entries > ARRAY_SIZE(params->e820_table)) {
603 		u32 nr_e820ext = nr_entries - ARRAY_SIZE(params->e820_table);
604 
605 		add_e820ext(params, e820ext, nr_e820ext);
606 		nr_entries -= nr_e820ext;
607 	}
608 
609 	params->e820_entries = (u8)nr_entries;
610 
611 	return EFI_SUCCESS;
612 }
613 
alloc_e820ext(u32 nr_desc,struct setup_data ** e820ext,u32 * e820ext_size)614 static efi_status_t alloc_e820ext(u32 nr_desc, struct setup_data **e820ext,
615 				  u32 *e820ext_size)
616 {
617 	efi_status_t status;
618 	unsigned long size;
619 
620 	size = sizeof(struct setup_data) +
621 		sizeof(struct e820_entry) * nr_desc;
622 
623 	if (*e820ext) {
624 		efi_call_early(free_pool, *e820ext);
625 		*e820ext = NULL;
626 		*e820ext_size = 0;
627 	}
628 
629 	status = efi_call_early(allocate_pool, EFI_LOADER_DATA,
630 				size, (void **)e820ext);
631 	if (status == EFI_SUCCESS)
632 		*e820ext_size = size;
633 
634 	return status;
635 }
636 
637 struct exit_boot_struct {
638 	struct boot_params	*boot_params;
639 	struct efi_info		*efi;
640 	struct setup_data	*e820ext;
641 	__u32			e820ext_size;
642 };
643 
exit_boot_func(efi_system_table_t * sys_table_arg,struct efi_boot_memmap * map,void * priv)644 static efi_status_t exit_boot_func(efi_system_table_t *sys_table_arg,
645 				   struct efi_boot_memmap *map,
646 				   void *priv)
647 {
648 	static bool first = true;
649 	const char *signature;
650 	__u32 nr_desc;
651 	efi_status_t status;
652 	struct exit_boot_struct *p = priv;
653 
654 	if (first) {
655 		nr_desc = *map->buff_size / *map->desc_size;
656 		if (nr_desc > ARRAY_SIZE(p->boot_params->e820_table)) {
657 			u32 nr_e820ext = nr_desc -
658 					ARRAY_SIZE(p->boot_params->e820_table);
659 
660 			status = alloc_e820ext(nr_e820ext, &p->e820ext,
661 					       &p->e820ext_size);
662 			if (status != EFI_SUCCESS)
663 				return status;
664 		}
665 		first = false;
666 	}
667 
668 	signature = efi_is_64bit() ? EFI64_LOADER_SIGNATURE
669 				   : EFI32_LOADER_SIGNATURE;
670 	memcpy(&p->efi->efi_loader_signature, signature, sizeof(__u32));
671 
672 	p->efi->efi_systab		= (unsigned long)sys_table_arg;
673 	p->efi->efi_memdesc_size	= *map->desc_size;
674 	p->efi->efi_memdesc_version	= *map->desc_ver;
675 	p->efi->efi_memmap		= (unsigned long)*map->map;
676 	p->efi->efi_memmap_size		= *map->map_size;
677 
678 #ifdef CONFIG_X86_64
679 	p->efi->efi_systab_hi		= (unsigned long)sys_table_arg >> 32;
680 	p->efi->efi_memmap_hi		= (unsigned long)*map->map >> 32;
681 #endif
682 
683 	return EFI_SUCCESS;
684 }
685 
exit_boot(struct boot_params * boot_params,void * handle)686 static efi_status_t exit_boot(struct boot_params *boot_params, void *handle)
687 {
688 	unsigned long map_sz, key, desc_size, buff_size;
689 	efi_memory_desc_t *mem_map;
690 	struct setup_data *e820ext;
691 	__u32 e820ext_size;
692 	efi_status_t status;
693 	__u32 desc_version;
694 	struct efi_boot_memmap map;
695 	struct exit_boot_struct priv;
696 
697 	map.map			= &mem_map;
698 	map.map_size		= &map_sz;
699 	map.desc_size		= &desc_size;
700 	map.desc_ver		= &desc_version;
701 	map.key_ptr		= &key;
702 	map.buff_size		= &buff_size;
703 	priv.boot_params	= boot_params;
704 	priv.efi		= &boot_params->efi_info;
705 	priv.e820ext		= NULL;
706 	priv.e820ext_size	= 0;
707 
708 	/* Might as well exit boot services now */
709 	status = efi_exit_boot_services(sys_table, handle, &map, &priv,
710 					exit_boot_func);
711 	if (status != EFI_SUCCESS)
712 		return status;
713 
714 	e820ext			= priv.e820ext;
715 	e820ext_size		= priv.e820ext_size;
716 
717 	/* Historic? */
718 	boot_params->alt_mem_k	= 32 * 1024;
719 
720 	status = setup_e820(boot_params, e820ext, e820ext_size);
721 	if (status != EFI_SUCCESS)
722 		return status;
723 
724 	return EFI_SUCCESS;
725 }
726 
727 /*
728  * On success we return a pointer to a boot_params structure, and NULL
729  * on failure.
730  */
731 struct boot_params *
efi_main(struct efi_config * c,struct boot_params * boot_params)732 efi_main(struct efi_config *c, struct boot_params *boot_params)
733 {
734 	struct desc_ptr *gdt = NULL;
735 	efi_loaded_image_t *image;
736 	struct setup_header *hdr = &boot_params->hdr;
737 	efi_status_t status;
738 	struct desc_struct *desc;
739 	void *handle;
740 	efi_system_table_t *_table;
741 
742 	efi_early = c;
743 
744 	_table = (efi_system_table_t *)(unsigned long)efi_early->table;
745 	handle = (void *)(unsigned long)efi_early->image_handle;
746 
747 	sys_table = _table;
748 
749 	/* Check if we were booted by the EFI firmware */
750 	if (sys_table->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE)
751 		goto fail;
752 
753 	if (efi_is_64bit())
754 		setup_boot_services64(efi_early);
755 	else
756 		setup_boot_services32(efi_early);
757 
758 	/*
759 	 * If the boot loader gave us a value for secure_boot then we use that,
760 	 * otherwise we ask the BIOS.
761 	 */
762 	if (boot_params->secure_boot == efi_secureboot_mode_unset)
763 		boot_params->secure_boot = efi_get_secureboot(sys_table);
764 
765 	/* Ask the firmware to clear memory on unclean shutdown */
766 	efi_enable_reset_attack_mitigation(sys_table);
767 	efi_retrieve_tpm2_eventlog(sys_table);
768 
769 	setup_graphics(boot_params);
770 
771 	setup_efi_pci(boot_params);
772 
773 	setup_quirks(boot_params);
774 
775 	status = efi_call_early(allocate_pool, EFI_LOADER_DATA,
776 				sizeof(*gdt), (void **)&gdt);
777 	if (status != EFI_SUCCESS) {
778 		efi_printk(sys_table, "Failed to allocate memory for 'gdt' structure\n");
779 		goto fail;
780 	}
781 
782 	gdt->size = 0x800;
783 	status = efi_low_alloc(sys_table, gdt->size, 8,
784 			   (unsigned long *)&gdt->address);
785 	if (status != EFI_SUCCESS) {
786 		efi_printk(sys_table, "Failed to allocate memory for 'gdt'\n");
787 		goto fail;
788 	}
789 
790 	/*
791 	 * If the kernel isn't already loaded at the preferred load
792 	 * address, relocate it.
793 	 */
794 	if (hdr->pref_address != hdr->code32_start) {
795 		unsigned long bzimage_addr = hdr->code32_start;
796 		status = efi_relocate_kernel(sys_table, &bzimage_addr,
797 					     hdr->init_size, hdr->init_size,
798 					     hdr->pref_address,
799 					     hdr->kernel_alignment);
800 		if (status != EFI_SUCCESS) {
801 			efi_printk(sys_table, "efi_relocate_kernel() failed!\n");
802 			goto fail;
803 		}
804 
805 		hdr->pref_address = hdr->code32_start;
806 		hdr->code32_start = bzimage_addr;
807 	}
808 
809 	status = exit_boot(boot_params, handle);
810 	if (status != EFI_SUCCESS) {
811 		efi_printk(sys_table, "exit_boot() failed!\n");
812 		goto fail;
813 	}
814 
815 	memset((char *)gdt->address, 0x0, gdt->size);
816 	desc = (struct desc_struct *)gdt->address;
817 
818 	/* The first GDT is a dummy. */
819 	desc++;
820 
821 	if (IS_ENABLED(CONFIG_X86_64)) {
822 		/* __KERNEL32_CS */
823 		desc->limit0	= 0xffff;
824 		desc->base0	= 0x0000;
825 		desc->base1	= 0x0000;
826 		desc->type	= SEG_TYPE_CODE | SEG_TYPE_EXEC_READ;
827 		desc->s		= DESC_TYPE_CODE_DATA;
828 		desc->dpl	= 0;
829 		desc->p		= 1;
830 		desc->limit1	= 0xf;
831 		desc->avl	= 0;
832 		desc->l		= 0;
833 		desc->d		= SEG_OP_SIZE_32BIT;
834 		desc->g		= SEG_GRANULARITY_4KB;
835 		desc->base2	= 0x00;
836 
837 		desc++;
838 	} else {
839 		/* Second entry is unused on 32-bit */
840 		desc++;
841 	}
842 
843 	/* __KERNEL_CS */
844 	desc->limit0	= 0xffff;
845 	desc->base0	= 0x0000;
846 	desc->base1	= 0x0000;
847 	desc->type	= SEG_TYPE_CODE | SEG_TYPE_EXEC_READ;
848 	desc->s		= DESC_TYPE_CODE_DATA;
849 	desc->dpl	= 0;
850 	desc->p		= 1;
851 	desc->limit1	= 0xf;
852 	desc->avl	= 0;
853 
854 	if (IS_ENABLED(CONFIG_X86_64)) {
855 		desc->l = 1;
856 		desc->d = 0;
857 	} else {
858 		desc->l = 0;
859 		desc->d = SEG_OP_SIZE_32BIT;
860 	}
861 	desc->g		= SEG_GRANULARITY_4KB;
862 	desc->base2	= 0x00;
863 	desc++;
864 
865 	/* __KERNEL_DS */
866 	desc->limit0	= 0xffff;
867 	desc->base0	= 0x0000;
868 	desc->base1	= 0x0000;
869 	desc->type	= SEG_TYPE_DATA | SEG_TYPE_READ_WRITE;
870 	desc->s		= DESC_TYPE_CODE_DATA;
871 	desc->dpl	= 0;
872 	desc->p		= 1;
873 	desc->limit1	= 0xf;
874 	desc->avl	= 0;
875 	desc->l		= 0;
876 	desc->d		= SEG_OP_SIZE_32BIT;
877 	desc->g		= SEG_GRANULARITY_4KB;
878 	desc->base2	= 0x00;
879 	desc++;
880 
881 	if (IS_ENABLED(CONFIG_X86_64)) {
882 		/* Task segment value */
883 		desc->limit0	= 0x0000;
884 		desc->base0	= 0x0000;
885 		desc->base1	= 0x0000;
886 		desc->type	= SEG_TYPE_TSS;
887 		desc->s		= 0;
888 		desc->dpl	= 0;
889 		desc->p		= 1;
890 		desc->limit1	= 0x0;
891 		desc->avl	= 0;
892 		desc->l		= 0;
893 		desc->d		= 0;
894 		desc->g		= SEG_GRANULARITY_4KB;
895 		desc->base2	= 0x00;
896 		desc++;
897 	}
898 
899 	asm volatile("cli");
900 	asm volatile ("lgdt %0" : : "m" (*gdt));
901 
902 	return boot_params;
903 fail:
904 	efi_printk(sys_table, "efi_main() failed!\n");
905 
906 	return NULL;
907 }
908