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1 // SPDX-License-Identifier: GPL-2.0-only
2 
3 /* -----------------------------------------------------------------------
4  *
5  *   Copyright 2011 Intel Corporation; author Matt Fleming
6  *
7  * ----------------------------------------------------------------------- */
8 
9 #include <linux/efi.h>
10 #include <linux/pci.h>
11 
12 #include <asm/efi.h>
13 #include <asm/e820/types.h>
14 #include <asm/setup.h>
15 #include <asm/desc.h>
16 #include <asm/boot.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 *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 	unsigned long ramdisk_addr;
394 	unsigned long ramdisk_size;
395 
396 	efi_early = c;
397 	sys_table = (efi_system_table_t *)(unsigned long)efi_early->table;
398 	handle = (void *)(unsigned long)efi_early->image_handle;
399 
400 	/* Check if we were booted by the EFI firmware */
401 	if (sys_table->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE)
402 		return NULL;
403 
404 	if (efi_is_64bit())
405 		setup_boot_services64(efi_early);
406 	else
407 		setup_boot_services32(efi_early);
408 
409 	status = efi_call_early(handle_protocol, handle,
410 				&proto, (void *)&image);
411 	if (status != EFI_SUCCESS) {
412 		efi_printk(sys_table, "Failed to get handle for LOADED_IMAGE_PROTOCOL\n");
413 		return NULL;
414 	}
415 
416 	status = efi_low_alloc(sys_table, 0x4000, 1,
417 			       (unsigned long *)&boot_params);
418 	if (status != EFI_SUCCESS) {
419 		efi_printk(sys_table, "Failed to allocate lowmem for boot params\n");
420 		return NULL;
421 	}
422 
423 	memset(boot_params, 0x0, 0x4000);
424 
425 	hdr = &boot_params->hdr;
426 	bi = &boot_params->apm_bios_info;
427 
428 	/* Copy the second sector to boot_params */
429 	memcpy(&hdr->jump, image->image_base + 512, 512);
430 
431 	/*
432 	 * Fill out some of the header fields ourselves because the
433 	 * EFI firmware loader doesn't load the first sector.
434 	 */
435 	hdr->root_flags	= 1;
436 	hdr->vid_mode	= 0xffff;
437 	hdr->boot_flag	= 0xAA55;
438 
439 	hdr->type_of_loader = 0x21;
440 
441 	/* Convert unicode cmdline to ascii */
442 	cmdline_ptr = efi_convert_cmdline(sys_table, image, &options_size);
443 	if (!cmdline_ptr)
444 		goto fail;
445 
446 	hdr->cmd_line_ptr = (unsigned long)cmdline_ptr;
447 	/* Fill in upper bits of command line address, NOP on 32 bit  */
448 	boot_params->ext_cmd_line_ptr = (u64)(unsigned long)cmdline_ptr >> 32;
449 
450 	hdr->ramdisk_image = 0;
451 	hdr->ramdisk_size = 0;
452 
453 	/* Clear APM BIOS info */
454 	memset(bi, 0, sizeof(*bi));
455 
456 	status = efi_parse_options(cmdline_ptr);
457 	if (status != EFI_SUCCESS)
458 		goto fail2;
459 
460 	status = handle_cmdline_files(sys_table, image,
461 				      (char *)(unsigned long)hdr->cmd_line_ptr,
462 				      "initrd=", hdr->initrd_addr_max,
463 				      &ramdisk_addr, &ramdisk_size);
464 
465 	if (status != EFI_SUCCESS &&
466 	    hdr->xloadflags & XLF_CAN_BE_LOADED_ABOVE_4G) {
467 		efi_printk(sys_table, "Trying to load files to higher address\n");
468 		status = handle_cmdline_files(sys_table, image,
469 				      (char *)(unsigned long)hdr->cmd_line_ptr,
470 				      "initrd=", -1UL,
471 				      &ramdisk_addr, &ramdisk_size);
472 	}
473 
474 	if (status != EFI_SUCCESS)
475 		goto fail2;
476 	hdr->ramdisk_image = ramdisk_addr & 0xffffffff;
477 	hdr->ramdisk_size  = ramdisk_size & 0xffffffff;
478 	boot_params->ext_ramdisk_image = (u64)ramdisk_addr >> 32;
479 	boot_params->ext_ramdisk_size  = (u64)ramdisk_size >> 32;
480 
481 	return boot_params;
482 
483 fail2:
484 	efi_free(sys_table, options_size, hdr->cmd_line_ptr);
485 fail:
486 	efi_free(sys_table, 0x4000, (unsigned long)boot_params);
487 
488 	return NULL;
489 }
490 
add_e820ext(struct boot_params * params,struct setup_data * e820ext,u32 nr_entries)491 static void add_e820ext(struct boot_params *params,
492 			struct setup_data *e820ext, u32 nr_entries)
493 {
494 	struct setup_data *data;
495 
496 	e820ext->type = SETUP_E820_EXT;
497 	e820ext->len  = nr_entries * sizeof(struct boot_e820_entry);
498 	e820ext->next = 0;
499 
500 	data = (struct setup_data *)(unsigned long)params->hdr.setup_data;
501 
502 	while (data && data->next)
503 		data = (struct setup_data *)(unsigned long)data->next;
504 
505 	if (data)
506 		data->next = (unsigned long)e820ext;
507 	else
508 		params->hdr.setup_data = (unsigned long)e820ext;
509 }
510 
511 static efi_status_t
setup_e820(struct boot_params * params,struct setup_data * e820ext,u32 e820ext_size)512 setup_e820(struct boot_params *params, struct setup_data *e820ext, u32 e820ext_size)
513 {
514 	struct boot_e820_entry *entry = params->e820_table;
515 	struct efi_info *efi = &params->efi_info;
516 	struct boot_e820_entry *prev = NULL;
517 	u32 nr_entries;
518 	u32 nr_desc;
519 	int i;
520 
521 	nr_entries = 0;
522 	nr_desc = efi->efi_memmap_size / efi->efi_memdesc_size;
523 
524 	for (i = 0; i < nr_desc; i++) {
525 		efi_memory_desc_t *d;
526 		unsigned int e820_type = 0;
527 		unsigned long m = efi->efi_memmap;
528 
529 #ifdef CONFIG_X86_64
530 		m |= (u64)efi->efi_memmap_hi << 32;
531 #endif
532 
533 		d = efi_early_memdesc_ptr(m, efi->efi_memdesc_size, i);
534 		switch (d->type) {
535 		case EFI_RESERVED_TYPE:
536 		case EFI_RUNTIME_SERVICES_CODE:
537 		case EFI_RUNTIME_SERVICES_DATA:
538 		case EFI_MEMORY_MAPPED_IO:
539 		case EFI_MEMORY_MAPPED_IO_PORT_SPACE:
540 		case EFI_PAL_CODE:
541 			e820_type = E820_TYPE_RESERVED;
542 			break;
543 
544 		case EFI_UNUSABLE_MEMORY:
545 			e820_type = E820_TYPE_UNUSABLE;
546 			break;
547 
548 		case EFI_ACPI_RECLAIM_MEMORY:
549 			e820_type = E820_TYPE_ACPI;
550 			break;
551 
552 		case EFI_LOADER_CODE:
553 		case EFI_LOADER_DATA:
554 		case EFI_BOOT_SERVICES_CODE:
555 		case EFI_BOOT_SERVICES_DATA:
556 		case EFI_CONVENTIONAL_MEMORY:
557 			e820_type = E820_TYPE_RAM;
558 			break;
559 
560 		case EFI_ACPI_MEMORY_NVS:
561 			e820_type = E820_TYPE_NVS;
562 			break;
563 
564 		case EFI_PERSISTENT_MEMORY:
565 			e820_type = E820_TYPE_PMEM;
566 			break;
567 
568 		default:
569 			continue;
570 		}
571 
572 		/* Merge adjacent mappings */
573 		if (prev && prev->type == e820_type &&
574 		    (prev->addr + prev->size) == d->phys_addr) {
575 			prev->size += d->num_pages << 12;
576 			continue;
577 		}
578 
579 		if (nr_entries == ARRAY_SIZE(params->e820_table)) {
580 			u32 need = (nr_desc - i) * sizeof(struct e820_entry) +
581 				   sizeof(struct setup_data);
582 
583 			if (!e820ext || e820ext_size < need)
584 				return EFI_BUFFER_TOO_SMALL;
585 
586 			/* boot_params map full, switch to e820 extended */
587 			entry = (struct boot_e820_entry *)e820ext->data;
588 		}
589 
590 		entry->addr = d->phys_addr;
591 		entry->size = d->num_pages << PAGE_SHIFT;
592 		entry->type = e820_type;
593 		prev = entry++;
594 		nr_entries++;
595 	}
596 
597 	if (nr_entries > ARRAY_SIZE(params->e820_table)) {
598 		u32 nr_e820ext = nr_entries - ARRAY_SIZE(params->e820_table);
599 
600 		add_e820ext(params, e820ext, nr_e820ext);
601 		nr_entries -= nr_e820ext;
602 	}
603 
604 	params->e820_entries = (u8)nr_entries;
605 
606 	return EFI_SUCCESS;
607 }
608 
alloc_e820ext(u32 nr_desc,struct setup_data ** e820ext,u32 * e820ext_size)609 static efi_status_t alloc_e820ext(u32 nr_desc, struct setup_data **e820ext,
610 				  u32 *e820ext_size)
611 {
612 	efi_status_t status;
613 	unsigned long size;
614 
615 	size = sizeof(struct setup_data) +
616 		sizeof(struct e820_entry) * nr_desc;
617 
618 	if (*e820ext) {
619 		efi_call_early(free_pool, *e820ext);
620 		*e820ext = NULL;
621 		*e820ext_size = 0;
622 	}
623 
624 	status = efi_call_early(allocate_pool, EFI_LOADER_DATA,
625 				size, (void **)e820ext);
626 	if (status == EFI_SUCCESS)
627 		*e820ext_size = size;
628 
629 	return status;
630 }
631 
allocate_e820(struct boot_params * params,struct setup_data ** e820ext,u32 * e820ext_size)632 static efi_status_t allocate_e820(struct boot_params *params,
633 				  struct setup_data **e820ext,
634 				  u32 *e820ext_size)
635 {
636 	unsigned long map_size, desc_size, buff_size;
637 	struct efi_boot_memmap boot_map;
638 	efi_memory_desc_t *map;
639 	efi_status_t status;
640 	__u32 nr_desc;
641 
642 	boot_map.map		= &map;
643 	boot_map.map_size	= &map_size;
644 	boot_map.desc_size	= &desc_size;
645 	boot_map.desc_ver	= NULL;
646 	boot_map.key_ptr	= NULL;
647 	boot_map.buff_size	= &buff_size;
648 
649 	status = efi_get_memory_map(sys_table, &boot_map);
650 	if (status != EFI_SUCCESS)
651 		return status;
652 
653 	nr_desc = buff_size / desc_size;
654 
655 	if (nr_desc > ARRAY_SIZE(params->e820_table)) {
656 		u32 nr_e820ext = nr_desc - ARRAY_SIZE(params->e820_table);
657 
658 		status = alloc_e820ext(nr_e820ext, e820ext, e820ext_size);
659 		if (status != EFI_SUCCESS)
660 			return status;
661 	}
662 
663 	return EFI_SUCCESS;
664 }
665 
666 struct exit_boot_struct {
667 	struct boot_params	*boot_params;
668 	struct efi_info		*efi;
669 };
670 
exit_boot_func(efi_system_table_t * sys_table_arg,struct efi_boot_memmap * map,void * priv)671 static efi_status_t exit_boot_func(efi_system_table_t *sys_table_arg,
672 				   struct efi_boot_memmap *map,
673 				   void *priv)
674 {
675 	const char *signature;
676 	struct exit_boot_struct *p = priv;
677 
678 	signature = efi_is_64bit() ? EFI64_LOADER_SIGNATURE
679 				   : EFI32_LOADER_SIGNATURE;
680 	memcpy(&p->efi->efi_loader_signature, signature, sizeof(__u32));
681 
682 	p->efi->efi_systab		= (unsigned long)sys_table_arg;
683 	p->efi->efi_memdesc_size	= *map->desc_size;
684 	p->efi->efi_memdesc_version	= *map->desc_ver;
685 	p->efi->efi_memmap		= (unsigned long)*map->map;
686 	p->efi->efi_memmap_size		= *map->map_size;
687 
688 #ifdef CONFIG_X86_64
689 	p->efi->efi_systab_hi		= (unsigned long)sys_table_arg >> 32;
690 	p->efi->efi_memmap_hi		= (unsigned long)*map->map >> 32;
691 #endif
692 
693 	return EFI_SUCCESS;
694 }
695 
exit_boot(struct boot_params * boot_params,void * handle)696 static efi_status_t exit_boot(struct boot_params *boot_params, void *handle)
697 {
698 	unsigned long map_sz, key, desc_size, buff_size;
699 	efi_memory_desc_t *mem_map;
700 	struct setup_data *e820ext = NULL;
701 	__u32 e820ext_size = 0;
702 	efi_status_t status;
703 	__u32 desc_version;
704 	struct efi_boot_memmap map;
705 	struct exit_boot_struct priv;
706 
707 	map.map			= &mem_map;
708 	map.map_size		= &map_sz;
709 	map.desc_size		= &desc_size;
710 	map.desc_ver		= &desc_version;
711 	map.key_ptr		= &key;
712 	map.buff_size		= &buff_size;
713 	priv.boot_params	= boot_params;
714 	priv.efi		= &boot_params->efi_info;
715 
716 	status = allocate_e820(boot_params, &e820ext, &e820ext_size);
717 	if (status != EFI_SUCCESS)
718 		return status;
719 
720 	/* Might as well exit boot services now */
721 	status = efi_exit_boot_services(sys_table, handle, &map, &priv,
722 					exit_boot_func);
723 	if (status != EFI_SUCCESS)
724 		return status;
725 
726 	/* Historic? */
727 	boot_params->alt_mem_k	= 32 * 1024;
728 
729 	status = setup_e820(boot_params, e820ext, e820ext_size);
730 	if (status != EFI_SUCCESS)
731 		return status;
732 
733 	return EFI_SUCCESS;
734 }
735 
736 /*
737  * On success we return a pointer to a boot_params structure, and NULL
738  * on failure.
739  */
740 struct boot_params *
efi_main(struct efi_config * c,struct boot_params * boot_params)741 efi_main(struct efi_config *c, struct boot_params *boot_params)
742 {
743 	struct desc_ptr *gdt = NULL;
744 	struct setup_header *hdr = &boot_params->hdr;
745 	efi_status_t status;
746 	struct desc_struct *desc;
747 	void *handle;
748 	efi_system_table_t *_table;
749 	unsigned long cmdline_paddr;
750 
751 	efi_early = c;
752 
753 	_table = (efi_system_table_t *)(unsigned long)efi_early->table;
754 	handle = (void *)(unsigned long)efi_early->image_handle;
755 
756 	sys_table = _table;
757 
758 	/* Check if we were booted by the EFI firmware */
759 	if (sys_table->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE)
760 		goto fail;
761 
762 	if (efi_is_64bit())
763 		setup_boot_services64(efi_early);
764 	else
765 		setup_boot_services32(efi_early);
766 
767 	/*
768 	 * make_boot_params() may have been called before efi_main(), in which
769 	 * case this is the second time we parse the cmdline. This is ok,
770 	 * parsing the cmdline multiple times does not have side-effects.
771 	 */
772 	cmdline_paddr = ((u64)hdr->cmd_line_ptr |
773 			 ((u64)boot_params->ext_cmd_line_ptr << 32));
774 	efi_parse_options((char *)cmdline_paddr);
775 
776 	/*
777 	 * If the boot loader gave us a value for secure_boot then we use that,
778 	 * otherwise we ask the BIOS.
779 	 */
780 	if (boot_params->secure_boot == efi_secureboot_mode_unset)
781 		boot_params->secure_boot = efi_get_secureboot(sys_table);
782 
783 	/* Ask the firmware to clear memory on unclean shutdown */
784 	efi_enable_reset_attack_mitigation(sys_table);
785 	efi_retrieve_tpm2_eventlog(sys_table);
786 
787 	setup_graphics(boot_params);
788 
789 	setup_efi_pci(boot_params);
790 
791 	setup_quirks(boot_params);
792 
793 	status = efi_call_early(allocate_pool, EFI_LOADER_DATA,
794 				sizeof(*gdt), (void **)&gdt);
795 	if (status != EFI_SUCCESS) {
796 		efi_printk(sys_table, "Failed to allocate memory for 'gdt' structure\n");
797 		goto fail;
798 	}
799 
800 	gdt->size = 0x800;
801 	status = efi_low_alloc(sys_table, gdt->size, 8,
802 			   (unsigned long *)&gdt->address);
803 	if (status != EFI_SUCCESS) {
804 		efi_printk(sys_table, "Failed to allocate memory for 'gdt'\n");
805 		goto fail;
806 	}
807 
808 	/*
809 	 * If the kernel isn't already loaded at the preferred load
810 	 * address, relocate it.
811 	 */
812 	if (hdr->pref_address != hdr->code32_start) {
813 		unsigned long bzimage_addr = hdr->code32_start;
814 		status = efi_relocate_kernel(sys_table, &bzimage_addr,
815 					     hdr->init_size, hdr->init_size,
816 					     hdr->pref_address,
817 					     hdr->kernel_alignment,
818 					     LOAD_PHYSICAL_ADDR);
819 		if (status != EFI_SUCCESS) {
820 			efi_printk(sys_table, "efi_relocate_kernel() failed!\n");
821 			goto fail;
822 		}
823 
824 		hdr->pref_address = hdr->code32_start;
825 		hdr->code32_start = bzimage_addr;
826 	}
827 
828 	status = exit_boot(boot_params, handle);
829 	if (status != EFI_SUCCESS) {
830 		efi_printk(sys_table, "exit_boot() failed!\n");
831 		goto fail;
832 	}
833 
834 	memset((char *)gdt->address, 0x0, gdt->size);
835 	desc = (struct desc_struct *)gdt->address;
836 
837 	/* The first GDT is a dummy. */
838 	desc++;
839 
840 	if (IS_ENABLED(CONFIG_X86_64)) {
841 		/* __KERNEL32_CS */
842 		desc->limit0	= 0xffff;
843 		desc->base0	= 0x0000;
844 		desc->base1	= 0x0000;
845 		desc->type	= SEG_TYPE_CODE | SEG_TYPE_EXEC_READ;
846 		desc->s		= DESC_TYPE_CODE_DATA;
847 		desc->dpl	= 0;
848 		desc->p		= 1;
849 		desc->limit1	= 0xf;
850 		desc->avl	= 0;
851 		desc->l		= 0;
852 		desc->d		= SEG_OP_SIZE_32BIT;
853 		desc->g		= SEG_GRANULARITY_4KB;
854 		desc->base2	= 0x00;
855 
856 		desc++;
857 	} else {
858 		/* Second entry is unused on 32-bit */
859 		desc++;
860 	}
861 
862 	/* __KERNEL_CS */
863 	desc->limit0	= 0xffff;
864 	desc->base0	= 0x0000;
865 	desc->base1	= 0x0000;
866 	desc->type	= SEG_TYPE_CODE | SEG_TYPE_EXEC_READ;
867 	desc->s		= DESC_TYPE_CODE_DATA;
868 	desc->dpl	= 0;
869 	desc->p		= 1;
870 	desc->limit1	= 0xf;
871 	desc->avl	= 0;
872 
873 	if (IS_ENABLED(CONFIG_X86_64)) {
874 		desc->l = 1;
875 		desc->d = 0;
876 	} else {
877 		desc->l = 0;
878 		desc->d = SEG_OP_SIZE_32BIT;
879 	}
880 	desc->g		= SEG_GRANULARITY_4KB;
881 	desc->base2	= 0x00;
882 	desc++;
883 
884 	/* __KERNEL_DS */
885 	desc->limit0	= 0xffff;
886 	desc->base0	= 0x0000;
887 	desc->base1	= 0x0000;
888 	desc->type	= SEG_TYPE_DATA | SEG_TYPE_READ_WRITE;
889 	desc->s		= DESC_TYPE_CODE_DATA;
890 	desc->dpl	= 0;
891 	desc->p		= 1;
892 	desc->limit1	= 0xf;
893 	desc->avl	= 0;
894 	desc->l		= 0;
895 	desc->d		= SEG_OP_SIZE_32BIT;
896 	desc->g		= SEG_GRANULARITY_4KB;
897 	desc->base2	= 0x00;
898 	desc++;
899 
900 	if (IS_ENABLED(CONFIG_X86_64)) {
901 		/* Task segment value */
902 		desc->limit0	= 0x0000;
903 		desc->base0	= 0x0000;
904 		desc->base1	= 0x0000;
905 		desc->type	= SEG_TYPE_TSS;
906 		desc->s		= 0;
907 		desc->dpl	= 0;
908 		desc->p		= 1;
909 		desc->limit1	= 0x0;
910 		desc->avl	= 0;
911 		desc->l		= 0;
912 		desc->d		= 0;
913 		desc->g		= SEG_GRANULARITY_4KB;
914 		desc->base2	= 0x00;
915 		desc++;
916 	}
917 
918 	asm volatile("cli");
919 	asm volatile ("lgdt %0" : : "m" (*gdt));
920 
921 	return boot_params;
922 fail:
923 	efi_printk(sys_table, "efi_main() failed!\n");
924 
925 	return NULL;
926 }
927