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1 
2 /* -----------------------------------------------------------------------
3  *
4  *   Copyright 2011 Intel Corporation; author Matt Fleming
5  *
6  *   This file is part of the Linux kernel, and is made available under
7  *   the terms of the GNU General Public License version 2.
8  *
9  * ----------------------------------------------------------------------- */
10 
11 #include <linux/efi.h>
12 #include <linux/pci.h>
13 
14 #include <asm/efi.h>
15 #include <asm/e820/types.h>
16 #include <asm/setup.h>
17 #include <asm/desc.h>
18 
19 #include "../string.h"
20 #include "eboot.h"
21 
22 static efi_system_table_t *sys_table;
23 
24 static struct efi_config *efi_early;
25 
__efi_early(void)26 __pure const struct efi_config *__efi_early(void)
27 {
28 	return efi_early;
29 }
30 
31 #define BOOT_SERVICES(bits)						\
32 static void setup_boot_services##bits(struct efi_config *c)		\
33 {									\
34 	efi_system_table_##bits##_t *table;				\
35 									\
36 	table = (typeof(table))sys_table;				\
37 									\
38 	c->runtime_services	= table->runtime;			\
39 	c->boot_services	= table->boottime;			\
40 	c->text_output		= table->con_out;			\
41 }
42 BOOT_SERVICES(32);
43 BOOT_SERVICES(64);
44 
efi_char16_printk(efi_system_table_t * table,efi_char16_t * str)45 void efi_char16_printk(efi_system_table_t *table, efi_char16_t *str)
46 {
47 	efi_call_proto(efi_simple_text_output_protocol, output_string,
48 		       efi_early->text_output, str);
49 }
50 
51 static efi_status_t
preserve_pci_rom_image(efi_pci_io_protocol_t * pci,struct pci_setup_rom ** __rom)52 preserve_pci_rom_image(efi_pci_io_protocol_t *pci, struct pci_setup_rom **__rom)
53 {
54 	struct pci_setup_rom *rom = NULL;
55 	efi_status_t status;
56 	unsigned long size;
57 	uint64_t romsize;
58 	void *romimage;
59 
60 	/*
61 	 * Some firmware images contain EFI function pointers at the place where
62 	 * the romimage and romsize fields are supposed to be. Typically the EFI
63 	 * code is mapped at high addresses, translating to an unrealistically
64 	 * large romsize. The UEFI spec limits the size of option ROMs to 16
65 	 * MiB so we reject any ROMs over 16 MiB in size to catch this.
66 	 */
67 	romimage = (void *)(unsigned long)efi_table_attr(efi_pci_io_protocol,
68 							 romimage, pci);
69 	romsize = efi_table_attr(efi_pci_io_protocol, romsize, pci);
70 	if (!romimage || !romsize || romsize > SZ_16M)
71 		return EFI_INVALID_PARAMETER;
72 
73 	size = romsize + sizeof(*rom);
74 
75 	status = efi_call_early(allocate_pool, EFI_LOADER_DATA, size, &rom);
76 	if (status != EFI_SUCCESS) {
77 		efi_printk(sys_table, "Failed to allocate memory for 'rom'\n");
78 		return status;
79 	}
80 
81 	memset(rom, 0, sizeof(*rom));
82 
83 	rom->data.type	= SETUP_PCI;
84 	rom->data.len	= size - sizeof(struct setup_data);
85 	rom->data.next	= 0;
86 	rom->pcilen	= pci->romsize;
87 	*__rom = rom;
88 
89 	status = efi_call_proto(efi_pci_io_protocol, pci.read, pci,
90 				EfiPciIoWidthUint16, PCI_VENDOR_ID, 1,
91 				&rom->vendor);
92 
93 	if (status != EFI_SUCCESS) {
94 		efi_printk(sys_table, "Failed to read rom->vendor\n");
95 		goto free_struct;
96 	}
97 
98 	status = efi_call_proto(efi_pci_io_protocol, pci.read, pci,
99 				EfiPciIoWidthUint16, PCI_DEVICE_ID, 1,
100 				&rom->devid);
101 
102 	if (status != EFI_SUCCESS) {
103 		efi_printk(sys_table, "Failed to read rom->devid\n");
104 		goto free_struct;
105 	}
106 
107 	status = efi_call_proto(efi_pci_io_protocol, get_location, pci,
108 				&rom->segment, &rom->bus, &rom->device,
109 				&rom->function);
110 
111 	if (status != EFI_SUCCESS)
112 		goto free_struct;
113 
114 	memcpy(rom->romdata, romimage, romsize);
115 	return status;
116 
117 free_struct:
118 	efi_call_early(free_pool, rom);
119 	return status;
120 }
121 
122 /*
123  * There's no way to return an informative status from this function,
124  * because any analysis (and printing of error messages) needs to be
125  * done directly at the EFI function call-site.
126  *
127  * For example, EFI_INVALID_PARAMETER could indicate a bug or maybe we
128  * just didn't find any PCI devices, but there's no way to tell outside
129  * the context of the call.
130  */
setup_efi_pci(struct boot_params * params)131 static void setup_efi_pci(struct boot_params *params)
132 {
133 	efi_status_t status;
134 	void **pci_handle = NULL;
135 	efi_guid_t pci_proto = EFI_PCI_IO_PROTOCOL_GUID;
136 	unsigned long size = 0;
137 	unsigned long nr_pci;
138 	struct setup_data *data;
139 	int i;
140 
141 	status = efi_call_early(locate_handle,
142 				EFI_LOCATE_BY_PROTOCOL,
143 				&pci_proto, NULL, &size, pci_handle);
144 
145 	if (status == EFI_BUFFER_TOO_SMALL) {
146 		status = efi_call_early(allocate_pool,
147 					EFI_LOADER_DATA,
148 					size, (void **)&pci_handle);
149 
150 		if (status != EFI_SUCCESS) {
151 			efi_printk(sys_table, "Failed to allocate memory for 'pci_handle'\n");
152 			return;
153 		}
154 
155 		status = efi_call_early(locate_handle,
156 					EFI_LOCATE_BY_PROTOCOL, &pci_proto,
157 					NULL, &size, pci_handle);
158 	}
159 
160 	if (status != EFI_SUCCESS)
161 		goto free_handle;
162 
163 	data = (struct setup_data *)(unsigned long)params->hdr.setup_data;
164 
165 	while (data && data->next)
166 		data = (struct setup_data *)(unsigned long)data->next;
167 
168 	nr_pci = size / (efi_is_64bit() ? sizeof(u64) : sizeof(u32));
169 	for (i = 0; i < nr_pci; i++) {
170 		efi_pci_io_protocol_t *pci = NULL;
171 		struct pci_setup_rom *rom;
172 
173 		status = efi_call_early(handle_protocol,
174 					efi_is_64bit() ? ((u64 *)pci_handle)[i]
175 						       : ((u32 *)pci_handle)[i],
176 					&pci_proto, (void **)&pci);
177 		if (status != EFI_SUCCESS || !pci)
178 			continue;
179 
180 		status = preserve_pci_rom_image(pci, &rom);
181 		if (status != EFI_SUCCESS)
182 			continue;
183 
184 		if (data)
185 			data->next = (unsigned long)rom;
186 		else
187 			params->hdr.setup_data = (unsigned long)rom;
188 
189 		data = (struct setup_data *)rom;
190 	}
191 
192 free_handle:
193 	efi_call_early(free_pool, pci_handle);
194 }
195 
retrieve_apple_device_properties(struct boot_params * boot_params)196 static void retrieve_apple_device_properties(struct boot_params *boot_params)
197 {
198 	efi_guid_t guid = APPLE_PROPERTIES_PROTOCOL_GUID;
199 	struct setup_data *data, *new;
200 	efi_status_t status;
201 	u32 size = 0;
202 	void *p;
203 
204 	status = efi_call_early(locate_protocol, &guid, NULL, &p);
205 	if (status != EFI_SUCCESS)
206 		return;
207 
208 	if (efi_table_attr(apple_properties_protocol, version, p) != 0x10000) {
209 		efi_printk(sys_table, "Unsupported properties proto version\n");
210 		return;
211 	}
212 
213 	efi_call_proto(apple_properties_protocol, get_all, p, NULL, &size);
214 	if (!size)
215 		return;
216 
217 	do {
218 		status = efi_call_early(allocate_pool, EFI_LOADER_DATA,
219 					size + sizeof(struct setup_data), &new);
220 		if (status != EFI_SUCCESS) {
221 			efi_printk(sys_table, "Failed to allocate memory for 'properties'\n");
222 			return;
223 		}
224 
225 		status = efi_call_proto(apple_properties_protocol, get_all, p,
226 					new->data, &size);
227 
228 		if (status == EFI_BUFFER_TOO_SMALL)
229 			efi_call_early(free_pool, new);
230 	} while (status == EFI_BUFFER_TOO_SMALL);
231 
232 	new->type = SETUP_APPLE_PROPERTIES;
233 	new->len  = size;
234 	new->next = 0;
235 
236 	data = (struct setup_data *)(unsigned long)boot_params->hdr.setup_data;
237 	if (!data) {
238 		boot_params->hdr.setup_data = (unsigned long)new;
239 	} else {
240 		while (data->next)
241 			data = (struct setup_data *)(unsigned long)data->next;
242 		data->next = (unsigned long)new;
243 	}
244 }
245 
246 static const efi_char16_t apple[] = L"Apple";
247 
setup_quirks(struct boot_params * boot_params)248 static void setup_quirks(struct boot_params *boot_params)
249 {
250 	efi_char16_t *fw_vendor = (efi_char16_t *)(unsigned long)
251 		efi_table_attr(efi_system_table, fw_vendor, sys_table);
252 
253 	if (!memcmp(fw_vendor, apple, sizeof(apple))) {
254 		if (IS_ENABLED(CONFIG_APPLE_PROPERTIES))
255 			retrieve_apple_device_properties(boot_params);
256 	}
257 }
258 
259 /*
260  * See if we have Universal Graphics Adapter (UGA) protocol
261  */
262 static efi_status_t
setup_uga(struct screen_info * si,efi_guid_t * uga_proto,unsigned long size)263 setup_uga(struct screen_info *si, efi_guid_t *uga_proto, unsigned long size)
264 {
265 	efi_status_t status;
266 	u32 width, height;
267 	void **uga_handle = NULL;
268 	efi_uga_draw_protocol_t *uga = NULL, *first_uga;
269 	unsigned long nr_ugas;
270 	int i;
271 
272 	status = efi_call_early(allocate_pool, EFI_LOADER_DATA,
273 				size, (void **)&uga_handle);
274 	if (status != EFI_SUCCESS)
275 		return status;
276 
277 	status = efi_call_early(locate_handle,
278 				EFI_LOCATE_BY_PROTOCOL,
279 				uga_proto, NULL, &size, uga_handle);
280 	if (status != EFI_SUCCESS)
281 		goto free_handle;
282 
283 	height = 0;
284 	width = 0;
285 
286 	first_uga = NULL;
287 	nr_ugas = size / (efi_is_64bit() ? sizeof(u64) : sizeof(u32));
288 	for (i = 0; i < nr_ugas; i++) {
289 		efi_guid_t pciio_proto = EFI_PCI_IO_PROTOCOL_GUID;
290 		u32 w, h, depth, refresh;
291 		void *pciio;
292 		unsigned long handle = efi_is_64bit() ? ((u64 *)uga_handle)[i]
293 						      : ((u32 *)uga_handle)[i];
294 
295 		status = efi_call_early(handle_protocol, handle,
296 					uga_proto, (void **)&uga);
297 		if (status != EFI_SUCCESS)
298 			continue;
299 
300 		pciio = NULL;
301 		efi_call_early(handle_protocol, handle, &pciio_proto, &pciio);
302 
303 		status = efi_call_proto(efi_uga_draw_protocol, get_mode, uga,
304 					&w, &h, &depth, &refresh);
305 		if (status == EFI_SUCCESS && (!first_uga || pciio)) {
306 			width = w;
307 			height = h;
308 
309 			/*
310 			 * Once we've found a UGA supporting PCIIO,
311 			 * don't bother looking any further.
312 			 */
313 			if (pciio)
314 				break;
315 
316 			first_uga = uga;
317 		}
318 	}
319 
320 	if (!width && !height)
321 		goto free_handle;
322 
323 	/* EFI framebuffer */
324 	si->orig_video_isVGA	= VIDEO_TYPE_EFI;
325 
326 	si->lfb_depth		= 32;
327 	si->lfb_width		= width;
328 	si->lfb_height		= height;
329 
330 	si->red_size		= 8;
331 	si->red_pos		= 16;
332 	si->green_size		= 8;
333 	si->green_pos		= 8;
334 	si->blue_size		= 8;
335 	si->blue_pos		= 0;
336 	si->rsvd_size		= 8;
337 	si->rsvd_pos		= 24;
338 
339 free_handle:
340 	efi_call_early(free_pool, uga_handle);
341 
342 	return status;
343 }
344 
setup_graphics(struct boot_params * boot_params)345 void setup_graphics(struct boot_params *boot_params)
346 {
347 	efi_guid_t graphics_proto = EFI_GRAPHICS_OUTPUT_PROTOCOL_GUID;
348 	struct screen_info *si;
349 	efi_guid_t uga_proto = EFI_UGA_PROTOCOL_GUID;
350 	efi_status_t status;
351 	unsigned long size;
352 	void **gop_handle = NULL;
353 	void **uga_handle = NULL;
354 
355 	si = &boot_params->screen_info;
356 	memset(si, 0, sizeof(*si));
357 
358 	size = 0;
359 	status = efi_call_early(locate_handle,
360 				EFI_LOCATE_BY_PROTOCOL,
361 				&graphics_proto, NULL, &size, gop_handle);
362 	if (status == EFI_BUFFER_TOO_SMALL)
363 		status = efi_setup_gop(NULL, si, &graphics_proto, size);
364 
365 	if (status != EFI_SUCCESS) {
366 		size = 0;
367 		status = efi_call_early(locate_handle,
368 					EFI_LOCATE_BY_PROTOCOL,
369 					&uga_proto, NULL, &size, uga_handle);
370 		if (status == EFI_BUFFER_TOO_SMALL)
371 			setup_uga(si, &uga_proto, size);
372 	}
373 }
374 
375 /*
376  * Because the x86 boot code expects to be passed a boot_params we
377  * need to create one ourselves (usually the bootloader would create
378  * one for us).
379  *
380  * The caller is responsible for filling out ->code32_start in the
381  * returned boot_params.
382  */
make_boot_params(struct efi_config * c)383 struct boot_params *make_boot_params(struct efi_config *c)
384 {
385 	struct boot_params *boot_params;
386 	struct apm_bios_info *bi;
387 	struct setup_header *hdr;
388 	efi_loaded_image_t *image;
389 	void *options, *handle;
390 	efi_guid_t proto = LOADED_IMAGE_PROTOCOL_GUID;
391 	int options_size = 0;
392 	efi_status_t status;
393 	char *cmdline_ptr;
394 	u16 *s2;
395 	u8 *s1;
396 	int i;
397 	unsigned long ramdisk_addr;
398 	unsigned long ramdisk_size;
399 
400 	efi_early = c;
401 	sys_table = (efi_system_table_t *)(unsigned long)efi_early->table;
402 	handle = (void *)(unsigned long)efi_early->image_handle;
403 
404 	/* Check if we were booted by the EFI firmware */
405 	if (sys_table->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE)
406 		return NULL;
407 
408 	if (efi_is_64bit())
409 		setup_boot_services64(efi_early);
410 	else
411 		setup_boot_services32(efi_early);
412 
413 	status = efi_call_early(handle_protocol, handle,
414 				&proto, (void *)&image);
415 	if (status != EFI_SUCCESS) {
416 		efi_printk(sys_table, "Failed to get handle for LOADED_IMAGE_PROTOCOL\n");
417 		return NULL;
418 	}
419 
420 	status = efi_low_alloc(sys_table, 0x4000, 1,
421 			       (unsigned long *)&boot_params);
422 	if (status != EFI_SUCCESS) {
423 		efi_printk(sys_table, "Failed to allocate lowmem for boot params\n");
424 		return NULL;
425 	}
426 
427 	memset(boot_params, 0x0, 0x4000);
428 
429 	hdr = &boot_params->hdr;
430 	bi = &boot_params->apm_bios_info;
431 
432 	/* Copy the second sector to boot_params */
433 	memcpy(&hdr->jump, image->image_base + 512, 512);
434 
435 	/*
436 	 * Fill out some of the header fields ourselves because the
437 	 * EFI firmware loader doesn't load the first sector.
438 	 */
439 	hdr->root_flags	= 1;
440 	hdr->vid_mode	= 0xffff;
441 	hdr->boot_flag	= 0xAA55;
442 
443 	hdr->type_of_loader = 0x21;
444 
445 	/* Convert unicode cmdline to ascii */
446 	cmdline_ptr = efi_convert_cmdline(sys_table, image, &options_size);
447 	if (!cmdline_ptr)
448 		goto fail;
449 
450 	hdr->cmd_line_ptr = (unsigned long)cmdline_ptr;
451 	/* Fill in upper bits of command line address, NOP on 32 bit  */
452 	boot_params->ext_cmd_line_ptr = (u64)(unsigned long)cmdline_ptr >> 32;
453 
454 	hdr->ramdisk_image = 0;
455 	hdr->ramdisk_size = 0;
456 
457 	/* Clear APM BIOS info */
458 	memset(bi, 0, sizeof(*bi));
459 
460 	status = efi_parse_options(cmdline_ptr);
461 	if (status != EFI_SUCCESS)
462 		goto fail2;
463 
464 	status = handle_cmdline_files(sys_table, image,
465 				      (char *)(unsigned long)hdr->cmd_line_ptr,
466 				      "initrd=", hdr->initrd_addr_max,
467 				      &ramdisk_addr, &ramdisk_size);
468 
469 	if (status != EFI_SUCCESS &&
470 	    hdr->xloadflags & XLF_CAN_BE_LOADED_ABOVE_4G) {
471 		efi_printk(sys_table, "Trying to load files to higher address\n");
472 		status = handle_cmdline_files(sys_table, image,
473 				      (char *)(unsigned long)hdr->cmd_line_ptr,
474 				      "initrd=", -1UL,
475 				      &ramdisk_addr, &ramdisk_size);
476 	}
477 
478 	if (status != EFI_SUCCESS)
479 		goto fail2;
480 	hdr->ramdisk_image = ramdisk_addr & 0xffffffff;
481 	hdr->ramdisk_size  = ramdisk_size & 0xffffffff;
482 	boot_params->ext_ramdisk_image = (u64)ramdisk_addr >> 32;
483 	boot_params->ext_ramdisk_size  = (u64)ramdisk_size >> 32;
484 
485 	return boot_params;
486 
487 fail2:
488 	efi_free(sys_table, options_size, hdr->cmd_line_ptr);
489 fail:
490 	efi_free(sys_table, 0x4000, (unsigned long)boot_params);
491 
492 	return NULL;
493 }
494 
add_e820ext(struct boot_params * params,struct setup_data * e820ext,u32 nr_entries)495 static void add_e820ext(struct boot_params *params,
496 			struct setup_data *e820ext, u32 nr_entries)
497 {
498 	struct setup_data *data;
499 	efi_status_t status;
500 	unsigned long size;
501 
502 	e820ext->type = SETUP_E820_EXT;
503 	e820ext->len  = nr_entries * sizeof(struct boot_e820_entry);
504 	e820ext->next = 0;
505 
506 	data = (struct setup_data *)(unsigned long)params->hdr.setup_data;
507 
508 	while (data && data->next)
509 		data = (struct setup_data *)(unsigned long)data->next;
510 
511 	if (data)
512 		data->next = (unsigned long)e820ext;
513 	else
514 		params->hdr.setup_data = (unsigned long)e820ext;
515 }
516 
517 static efi_status_t
setup_e820(struct boot_params * params,struct setup_data * e820ext,u32 e820ext_size)518 setup_e820(struct boot_params *params, struct setup_data *e820ext, u32 e820ext_size)
519 {
520 	struct boot_e820_entry *entry = params->e820_table;
521 	struct efi_info *efi = &params->efi_info;
522 	struct boot_e820_entry *prev = NULL;
523 	u32 nr_entries;
524 	u32 nr_desc;
525 	int i;
526 
527 	nr_entries = 0;
528 	nr_desc = efi->efi_memmap_size / efi->efi_memdesc_size;
529 
530 	for (i = 0; i < nr_desc; i++) {
531 		efi_memory_desc_t *d;
532 		unsigned int e820_type = 0;
533 		unsigned long m = efi->efi_memmap;
534 
535 #ifdef CONFIG_X86_64
536 		m |= (u64)efi->efi_memmap_hi << 32;
537 #endif
538 
539 		d = efi_early_memdesc_ptr(m, efi->efi_memdesc_size, i);
540 		switch (d->type) {
541 		case EFI_RESERVED_TYPE:
542 		case EFI_RUNTIME_SERVICES_CODE:
543 		case EFI_RUNTIME_SERVICES_DATA:
544 		case EFI_MEMORY_MAPPED_IO:
545 		case EFI_MEMORY_MAPPED_IO_PORT_SPACE:
546 		case EFI_PAL_CODE:
547 			e820_type = E820_TYPE_RESERVED;
548 			break;
549 
550 		case EFI_UNUSABLE_MEMORY:
551 			e820_type = E820_TYPE_UNUSABLE;
552 			break;
553 
554 		case EFI_ACPI_RECLAIM_MEMORY:
555 			e820_type = E820_TYPE_ACPI;
556 			break;
557 
558 		case EFI_LOADER_CODE:
559 		case EFI_LOADER_DATA:
560 		case EFI_BOOT_SERVICES_CODE:
561 		case EFI_BOOT_SERVICES_DATA:
562 		case EFI_CONVENTIONAL_MEMORY:
563 			e820_type = E820_TYPE_RAM;
564 			break;
565 
566 		case EFI_ACPI_MEMORY_NVS:
567 			e820_type = E820_TYPE_NVS;
568 			break;
569 
570 		case EFI_PERSISTENT_MEMORY:
571 			e820_type = E820_TYPE_PMEM;
572 			break;
573 
574 		default:
575 			continue;
576 		}
577 
578 		/* Merge adjacent mappings */
579 		if (prev && prev->type == e820_type &&
580 		    (prev->addr + prev->size) == d->phys_addr) {
581 			prev->size += d->num_pages << 12;
582 			continue;
583 		}
584 
585 		if (nr_entries == ARRAY_SIZE(params->e820_table)) {
586 			u32 need = (nr_desc - i) * sizeof(struct e820_entry) +
587 				   sizeof(struct setup_data);
588 
589 			if (!e820ext || e820ext_size < need)
590 				return EFI_BUFFER_TOO_SMALL;
591 
592 			/* boot_params map full, switch to e820 extended */
593 			entry = (struct boot_e820_entry *)e820ext->data;
594 		}
595 
596 		entry->addr = d->phys_addr;
597 		entry->size = d->num_pages << PAGE_SHIFT;
598 		entry->type = e820_type;
599 		prev = entry++;
600 		nr_entries++;
601 	}
602 
603 	if (nr_entries > ARRAY_SIZE(params->e820_table)) {
604 		u32 nr_e820ext = nr_entries - ARRAY_SIZE(params->e820_table);
605 
606 		add_e820ext(params, e820ext, nr_e820ext);
607 		nr_entries -= nr_e820ext;
608 	}
609 
610 	params->e820_entries = (u8)nr_entries;
611 
612 	return EFI_SUCCESS;
613 }
614 
alloc_e820ext(u32 nr_desc,struct setup_data ** e820ext,u32 * e820ext_size)615 static efi_status_t alloc_e820ext(u32 nr_desc, struct setup_data **e820ext,
616 				  u32 *e820ext_size)
617 {
618 	efi_status_t status;
619 	unsigned long size;
620 
621 	size = sizeof(struct setup_data) +
622 		sizeof(struct e820_entry) * nr_desc;
623 
624 	if (*e820ext) {
625 		efi_call_early(free_pool, *e820ext);
626 		*e820ext = NULL;
627 		*e820ext_size = 0;
628 	}
629 
630 	status = efi_call_early(allocate_pool, EFI_LOADER_DATA,
631 				size, (void **)e820ext);
632 	if (status == EFI_SUCCESS)
633 		*e820ext_size = size;
634 
635 	return status;
636 }
637 
allocate_e820(struct boot_params * params,struct setup_data ** e820ext,u32 * e820ext_size)638 static efi_status_t allocate_e820(struct boot_params *params,
639 				  struct setup_data **e820ext,
640 				  u32 *e820ext_size)
641 {
642 	unsigned long map_size, desc_size, buff_size;
643 	struct efi_boot_memmap boot_map;
644 	efi_memory_desc_t *map;
645 	efi_status_t status;
646 	__u32 nr_desc;
647 
648 	boot_map.map		= &map;
649 	boot_map.map_size	= &map_size;
650 	boot_map.desc_size	= &desc_size;
651 	boot_map.desc_ver	= NULL;
652 	boot_map.key_ptr	= NULL;
653 	boot_map.buff_size	= &buff_size;
654 
655 	status = efi_get_memory_map(sys_table, &boot_map);
656 	if (status != EFI_SUCCESS)
657 		return status;
658 
659 	nr_desc = buff_size / desc_size;
660 
661 	if (nr_desc > ARRAY_SIZE(params->e820_table)) {
662 		u32 nr_e820ext = nr_desc - ARRAY_SIZE(params->e820_table);
663 
664 		status = alloc_e820ext(nr_e820ext, e820ext, e820ext_size);
665 		if (status != EFI_SUCCESS)
666 			return status;
667 	}
668 
669 	return EFI_SUCCESS;
670 }
671 
672 struct exit_boot_struct {
673 	struct boot_params	*boot_params;
674 	struct efi_info		*efi;
675 };
676 
exit_boot_func(efi_system_table_t * sys_table_arg,struct efi_boot_memmap * map,void * priv)677 static efi_status_t exit_boot_func(efi_system_table_t *sys_table_arg,
678 				   struct efi_boot_memmap *map,
679 				   void *priv)
680 {
681 	const char *signature;
682 	__u32 nr_desc;
683 	efi_status_t status;
684 	struct exit_boot_struct *p = priv;
685 
686 	signature = efi_is_64bit() ? EFI64_LOADER_SIGNATURE
687 				   : EFI32_LOADER_SIGNATURE;
688 	memcpy(&p->efi->efi_loader_signature, signature, sizeof(__u32));
689 
690 	p->efi->efi_systab		= (unsigned long)sys_table_arg;
691 	p->efi->efi_memdesc_size	= *map->desc_size;
692 	p->efi->efi_memdesc_version	= *map->desc_ver;
693 	p->efi->efi_memmap		= (unsigned long)*map->map;
694 	p->efi->efi_memmap_size		= *map->map_size;
695 
696 #ifdef CONFIG_X86_64
697 	p->efi->efi_systab_hi		= (unsigned long)sys_table_arg >> 32;
698 	p->efi->efi_memmap_hi		= (unsigned long)*map->map >> 32;
699 #endif
700 
701 	return EFI_SUCCESS;
702 }
703 
exit_boot(struct boot_params * boot_params,void * handle)704 static efi_status_t exit_boot(struct boot_params *boot_params, void *handle)
705 {
706 	unsigned long map_sz, key, desc_size, buff_size;
707 	efi_memory_desc_t *mem_map;
708 	struct setup_data *e820ext = NULL;
709 	__u32 e820ext_size = 0;
710 	efi_status_t status;
711 	__u32 desc_version;
712 	struct efi_boot_memmap map;
713 	struct exit_boot_struct priv;
714 
715 	map.map			= &mem_map;
716 	map.map_size		= &map_sz;
717 	map.desc_size		= &desc_size;
718 	map.desc_ver		= &desc_version;
719 	map.key_ptr		= &key;
720 	map.buff_size		= &buff_size;
721 	priv.boot_params	= boot_params;
722 	priv.efi		= &boot_params->efi_info;
723 
724 	status = allocate_e820(boot_params, &e820ext, &e820ext_size);
725 	if (status != EFI_SUCCESS)
726 		return status;
727 
728 	/* Might as well exit boot services now */
729 	status = efi_exit_boot_services(sys_table, handle, &map, &priv,
730 					exit_boot_func);
731 	if (status != EFI_SUCCESS)
732 		return status;
733 
734 	/* Historic? */
735 	boot_params->alt_mem_k	= 32 * 1024;
736 
737 	status = setup_e820(boot_params, e820ext, e820ext_size);
738 	if (status != EFI_SUCCESS)
739 		return status;
740 
741 	return EFI_SUCCESS;
742 }
743 
744 /*
745  * On success we return a pointer to a boot_params structure, and NULL
746  * on failure.
747  */
748 struct boot_params *
efi_main(struct efi_config * c,struct boot_params * boot_params)749 efi_main(struct efi_config *c, struct boot_params *boot_params)
750 {
751 	struct desc_ptr *gdt = NULL;
752 	efi_loaded_image_t *image;
753 	struct setup_header *hdr = &boot_params->hdr;
754 	efi_status_t status;
755 	struct desc_struct *desc;
756 	void *handle;
757 	efi_system_table_t *_table;
758 	unsigned long cmdline_paddr;
759 
760 	efi_early = c;
761 
762 	_table = (efi_system_table_t *)(unsigned long)efi_early->table;
763 	handle = (void *)(unsigned long)efi_early->image_handle;
764 
765 	sys_table = _table;
766 
767 	/* Check if we were booted by the EFI firmware */
768 	if (sys_table->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE)
769 		goto fail;
770 
771 	if (efi_is_64bit())
772 		setup_boot_services64(efi_early);
773 	else
774 		setup_boot_services32(efi_early);
775 
776 	/*
777 	 * make_boot_params() may have been called before efi_main(), in which
778 	 * case this is the second time we parse the cmdline. This is ok,
779 	 * parsing the cmdline multiple times does not have side-effects.
780 	 */
781 	cmdline_paddr = ((u64)hdr->cmd_line_ptr |
782 			 ((u64)boot_params->ext_cmd_line_ptr << 32));
783 	efi_parse_options((char *)cmdline_paddr);
784 
785 	/*
786 	 * If the boot loader gave us a value for secure_boot then we use that,
787 	 * otherwise we ask the BIOS.
788 	 */
789 	if (boot_params->secure_boot == efi_secureboot_mode_unset)
790 		boot_params->secure_boot = efi_get_secureboot(sys_table);
791 
792 	/* Ask the firmware to clear memory on unclean shutdown */
793 	efi_enable_reset_attack_mitigation(sys_table);
794 	efi_retrieve_tpm2_eventlog(sys_table);
795 
796 	setup_graphics(boot_params);
797 
798 	setup_efi_pci(boot_params);
799 
800 	setup_quirks(boot_params);
801 
802 	status = efi_call_early(allocate_pool, EFI_LOADER_DATA,
803 				sizeof(*gdt), (void **)&gdt);
804 	if (status != EFI_SUCCESS) {
805 		efi_printk(sys_table, "Failed to allocate memory for 'gdt' structure\n");
806 		goto fail;
807 	}
808 
809 	gdt->size = 0x800;
810 	status = efi_low_alloc(sys_table, gdt->size, 8,
811 			   (unsigned long *)&gdt->address);
812 	if (status != EFI_SUCCESS) {
813 		efi_printk(sys_table, "Failed to allocate memory for 'gdt'\n");
814 		goto fail;
815 	}
816 
817 	/*
818 	 * If the kernel isn't already loaded at the preferred load
819 	 * address, relocate it.
820 	 */
821 	if (hdr->pref_address != hdr->code32_start) {
822 		unsigned long bzimage_addr = hdr->code32_start;
823 		status = efi_relocate_kernel(sys_table, &bzimage_addr,
824 					     hdr->init_size, hdr->init_size,
825 					     hdr->pref_address,
826 					     hdr->kernel_alignment);
827 		if (status != EFI_SUCCESS) {
828 			efi_printk(sys_table, "efi_relocate_kernel() failed!\n");
829 			goto fail;
830 		}
831 
832 		hdr->pref_address = hdr->code32_start;
833 		hdr->code32_start = bzimage_addr;
834 	}
835 
836 	status = exit_boot(boot_params, handle);
837 	if (status != EFI_SUCCESS) {
838 		efi_printk(sys_table, "exit_boot() failed!\n");
839 		goto fail;
840 	}
841 
842 	memset((char *)gdt->address, 0x0, gdt->size);
843 	desc = (struct desc_struct *)gdt->address;
844 
845 	/* The first GDT is a dummy. */
846 	desc++;
847 
848 	if (IS_ENABLED(CONFIG_X86_64)) {
849 		/* __KERNEL32_CS */
850 		desc->limit0	= 0xffff;
851 		desc->base0	= 0x0000;
852 		desc->base1	= 0x0000;
853 		desc->type	= SEG_TYPE_CODE | SEG_TYPE_EXEC_READ;
854 		desc->s		= DESC_TYPE_CODE_DATA;
855 		desc->dpl	= 0;
856 		desc->p		= 1;
857 		desc->limit1	= 0xf;
858 		desc->avl	= 0;
859 		desc->l		= 0;
860 		desc->d		= SEG_OP_SIZE_32BIT;
861 		desc->g		= SEG_GRANULARITY_4KB;
862 		desc->base2	= 0x00;
863 
864 		desc++;
865 	} else {
866 		/* Second entry is unused on 32-bit */
867 		desc++;
868 	}
869 
870 	/* __KERNEL_CS */
871 	desc->limit0	= 0xffff;
872 	desc->base0	= 0x0000;
873 	desc->base1	= 0x0000;
874 	desc->type	= SEG_TYPE_CODE | SEG_TYPE_EXEC_READ;
875 	desc->s		= DESC_TYPE_CODE_DATA;
876 	desc->dpl	= 0;
877 	desc->p		= 1;
878 	desc->limit1	= 0xf;
879 	desc->avl	= 0;
880 
881 	if (IS_ENABLED(CONFIG_X86_64)) {
882 		desc->l = 1;
883 		desc->d = 0;
884 	} else {
885 		desc->l = 0;
886 		desc->d = SEG_OP_SIZE_32BIT;
887 	}
888 	desc->g		= SEG_GRANULARITY_4KB;
889 	desc->base2	= 0x00;
890 	desc++;
891 
892 	/* __KERNEL_DS */
893 	desc->limit0	= 0xffff;
894 	desc->base0	= 0x0000;
895 	desc->base1	= 0x0000;
896 	desc->type	= SEG_TYPE_DATA | SEG_TYPE_READ_WRITE;
897 	desc->s		= DESC_TYPE_CODE_DATA;
898 	desc->dpl	= 0;
899 	desc->p		= 1;
900 	desc->limit1	= 0xf;
901 	desc->avl	= 0;
902 	desc->l		= 0;
903 	desc->d		= SEG_OP_SIZE_32BIT;
904 	desc->g		= SEG_GRANULARITY_4KB;
905 	desc->base2	= 0x00;
906 	desc++;
907 
908 	if (IS_ENABLED(CONFIG_X86_64)) {
909 		/* Task segment value */
910 		desc->limit0	= 0x0000;
911 		desc->base0	= 0x0000;
912 		desc->base1	= 0x0000;
913 		desc->type	= SEG_TYPE_TSS;
914 		desc->s		= 0;
915 		desc->dpl	= 0;
916 		desc->p		= 1;
917 		desc->limit1	= 0x0;
918 		desc->avl	= 0;
919 		desc->l		= 0;
920 		desc->d		= 0;
921 		desc->g		= SEG_GRANULARITY_4KB;
922 		desc->base2	= 0x00;
923 		desc++;
924 	}
925 
926 	asm volatile("cli");
927 	asm volatile ("lgdt %0" : : "m" (*gdt));
928 
929 	return boot_params;
930 fail:
931 	efi_printk(sys_table, "efi_main() failed!\n");
932 
933 	return NULL;
934 }
935