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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#include <linux/stddef.h>
 12
 13#include <asm/efi.h>
 14#include <asm/e820/types.h>
 15#include <asm/setup.h>
 16#include <asm/desc.h>
 17#include <asm/boot.h>
 18
 19#include "efistub.h"
 20
 21/* Maximum physical address for 64-bit kernel with 4-level paging */
 22#define MAXMEM_X86_64_4LEVEL (1ull << 46)
 23
 24const efi_system_table_t *efi_system_table;
 25extern u32 image_offset;
 26static efi_loaded_image_t *image = NULL;
 27
 28static efi_status_t
 29preserve_pci_rom_image(efi_pci_io_protocol_t *pci, struct pci_setup_rom **__rom)
 30{
 31	struct pci_setup_rom *rom = NULL;
 32	efi_status_t status;
 33	unsigned long size;
 34	uint64_t romsize;
 35	void *romimage;
 36
 37	/*
 38	 * Some firmware images contain EFI function pointers at the place where
 39	 * the romimage and romsize fields are supposed to be. Typically the EFI
 40	 * code is mapped at high addresses, translating to an unrealistically
 41	 * large romsize. The UEFI spec limits the size of option ROMs to 16
 42	 * MiB so we reject any ROMs over 16 MiB in size to catch this.
 43	 */
 44	romimage = efi_table_attr(pci, romimage);
 45	romsize = efi_table_attr(pci, romsize);
 46	if (!romimage || !romsize || romsize > SZ_16M)
 47		return EFI_INVALID_PARAMETER;
 48
 49	size = romsize + sizeof(*rom);
 50
 51	status = efi_bs_call(allocate_pool, EFI_LOADER_DATA, size,
 52			     (void **)&rom);
 53	if (status != EFI_SUCCESS) {
 54		efi_err("Failed to allocate memory for 'rom'\n");
 55		return status;
 56	}
 57
 58	memset(rom, 0, sizeof(*rom));
 59
 60	rom->data.type	= SETUP_PCI;
 61	rom->data.len	= size - sizeof(struct setup_data);
 62	rom->data.next	= 0;
 63	rom->pcilen	= pci->romsize;
 64	*__rom = rom;
 65
 66	status = efi_call_proto(pci, pci.read, EfiPciIoWidthUint16,
 67				PCI_VENDOR_ID, 1, &rom->vendor);
 68
 69	if (status != EFI_SUCCESS) {
 70		efi_err("Failed to read rom->vendor\n");
 71		goto free_struct;
 72	}
 73
 74	status = efi_call_proto(pci, pci.read, EfiPciIoWidthUint16,
 75				PCI_DEVICE_ID, 1, &rom->devid);
 76
 77	if (status != EFI_SUCCESS) {
 78		efi_err("Failed to read rom->devid\n");
 79		goto free_struct;
 80	}
 81
 82	status = efi_call_proto(pci, get_location, &rom->segment, &rom->bus,
 83				&rom->device, &rom->function);
 84
 85	if (status != EFI_SUCCESS)
 86		goto free_struct;
 87
 88	memcpy(rom->romdata, romimage, romsize);
 89	return status;
 90
 91free_struct:
 92	efi_bs_call(free_pool, rom);
 93	return status;
 94}
 95
 96/*
 97 * There's no way to return an informative status from this function,
 98 * because any analysis (and printing of error messages) needs to be
 99 * done directly at the EFI function call-site.
100 *
101 * For example, EFI_INVALID_PARAMETER could indicate a bug or maybe we
102 * just didn't find any PCI devices, but there's no way to tell outside
103 * the context of the call.
104 */
105static void setup_efi_pci(struct boot_params *params)
106{
107	efi_status_t status;
108	void **pci_handle = NULL;
109	efi_guid_t pci_proto = EFI_PCI_IO_PROTOCOL_GUID;
110	unsigned long size = 0;
111	struct setup_data *data;
112	efi_handle_t h;
113	int i;
114
115	status = efi_bs_call(locate_handle, EFI_LOCATE_BY_PROTOCOL,
116			     &pci_proto, NULL, &size, pci_handle);
117
118	if (status == EFI_BUFFER_TOO_SMALL) {
119		status = efi_bs_call(allocate_pool, EFI_LOADER_DATA, size,
120				     (void **)&pci_handle);
121
122		if (status != EFI_SUCCESS) {
123			efi_err("Failed to allocate memory for 'pci_handle'\n");
124			return;
125		}
126
127		status = efi_bs_call(locate_handle, EFI_LOCATE_BY_PROTOCOL,
128				     &pci_proto, NULL, &size, pci_handle);
129	}
130
131	if (status != EFI_SUCCESS)
132		goto free_handle;
133
134	data = (struct setup_data *)(unsigned long)params->hdr.setup_data;
135
136	while (data && data->next)
137		data = (struct setup_data *)(unsigned long)data->next;
138
139	for_each_efi_handle(h, pci_handle, size, i) {
140		efi_pci_io_protocol_t *pci = NULL;
141		struct pci_setup_rom *rom;
142
143		status = efi_bs_call(handle_protocol, h, &pci_proto,
144				     (void **)&pci);
145		if (status != EFI_SUCCESS || !pci)
146			continue;
147
148		status = preserve_pci_rom_image(pci, &rom);
149		if (status != EFI_SUCCESS)
150			continue;
151
152		if (data)
153			data->next = (unsigned long)rom;
154		else
155			params->hdr.setup_data = (unsigned long)rom;
156
157		data = (struct setup_data *)rom;
158	}
159
160free_handle:
161	efi_bs_call(free_pool, pci_handle);
162}
163
164static void retrieve_apple_device_properties(struct boot_params *boot_params)
165{
166	efi_guid_t guid = APPLE_PROPERTIES_PROTOCOL_GUID;
167	struct setup_data *data, *new;
168	efi_status_t status;
169	u32 size = 0;
170	apple_properties_protocol_t *p;
171
172	status = efi_bs_call(locate_protocol, &guid, NULL, (void **)&p);
173	if (status != EFI_SUCCESS)
174		return;
175
176	if (efi_table_attr(p, version) != 0x10000) {
177		efi_err("Unsupported properties proto version\n");
178		return;
179	}
180
181	efi_call_proto(p, get_all, NULL, &size);
182	if (!size)
183		return;
184
185	do {
186		status = efi_bs_call(allocate_pool, EFI_LOADER_DATA,
187				     size + sizeof(struct setup_data),
188				     (void **)&new);
189		if (status != EFI_SUCCESS) {
190			efi_err("Failed to allocate memory for 'properties'\n");
191			return;
192		}
193
194		status = efi_call_proto(p, get_all, new->data, &size);
195
196		if (status == EFI_BUFFER_TOO_SMALL)
197			efi_bs_call(free_pool, new);
198	} while (status == EFI_BUFFER_TOO_SMALL);
199
200	new->type = SETUP_APPLE_PROPERTIES;
201	new->len  = size;
202	new->next = 0;
203
204	data = (struct setup_data *)(unsigned long)boot_params->hdr.setup_data;
205	if (!data) {
206		boot_params->hdr.setup_data = (unsigned long)new;
207	} else {
208		while (data->next)
209			data = (struct setup_data *)(unsigned long)data->next;
210		data->next = (unsigned long)new;
211	}
212}
213
214static const efi_char16_t apple[] = L"Apple";
215
216static void setup_quirks(struct boot_params *boot_params)
217{
218	efi_char16_t *fw_vendor = (efi_char16_t *)(unsigned long)
219		efi_table_attr(efi_system_table, fw_vendor);
220
221	if (!memcmp(fw_vendor, apple, sizeof(apple))) {
222		if (IS_ENABLED(CONFIG_APPLE_PROPERTIES))
223			retrieve_apple_device_properties(boot_params);
224	}
225}
226
227/*
228 * See if we have Universal Graphics Adapter (UGA) protocol
229 */
230static efi_status_t
231setup_uga(struct screen_info *si, efi_guid_t *uga_proto, unsigned long size)
232{
233	efi_status_t status;
234	u32 width, height;
235	void **uga_handle = NULL;
236	efi_uga_draw_protocol_t *uga = NULL, *first_uga;
237	efi_handle_t handle;
238	int i;
239
240	status = efi_bs_call(allocate_pool, EFI_LOADER_DATA, size,
241			     (void **)&uga_handle);
242	if (status != EFI_SUCCESS)
243		return status;
244
245	status = efi_bs_call(locate_handle, EFI_LOCATE_BY_PROTOCOL,
246			     uga_proto, NULL, &size, uga_handle);
247	if (status != EFI_SUCCESS)
248		goto free_handle;
249
250	height = 0;
251	width = 0;
252
253	first_uga = NULL;
254	for_each_efi_handle(handle, uga_handle, size, i) {
255		efi_guid_t pciio_proto = EFI_PCI_IO_PROTOCOL_GUID;
256		u32 w, h, depth, refresh;
257		void *pciio;
258
259		status = efi_bs_call(handle_protocol, handle, uga_proto,
260				     (void **)&uga);
261		if (status != EFI_SUCCESS)
262			continue;
263
264		pciio = NULL;
265		efi_bs_call(handle_protocol, handle, &pciio_proto, &pciio);
266
267		status = efi_call_proto(uga, get_mode, &w, &h, &depth, &refresh);
268		if (status == EFI_SUCCESS && (!first_uga || pciio)) {
269			width = w;
270			height = h;
271
272			/*
273			 * Once we've found a UGA supporting PCIIO,
274			 * don't bother looking any further.
275			 */
276			if (pciio)
277				break;
278
279			first_uga = uga;
280		}
281	}
282
283	if (!width && !height)
284		goto free_handle;
285
286	/* EFI framebuffer */
287	si->orig_video_isVGA	= VIDEO_TYPE_EFI;
288
289	si->lfb_depth		= 32;
290	si->lfb_width		= width;
291	si->lfb_height		= height;
292
293	si->red_size		= 8;
294	si->red_pos		= 16;
295	si->green_size		= 8;
296	si->green_pos		= 8;
297	si->blue_size		= 8;
298	si->blue_pos		= 0;
299	si->rsvd_size		= 8;
300	si->rsvd_pos		= 24;
301
302free_handle:
303	efi_bs_call(free_pool, uga_handle);
304
305	return status;
306}
307
308static void setup_graphics(struct boot_params *boot_params)
309{
310	efi_guid_t graphics_proto = EFI_GRAPHICS_OUTPUT_PROTOCOL_GUID;
311	struct screen_info *si;
312	efi_guid_t uga_proto = EFI_UGA_PROTOCOL_GUID;
313	efi_status_t status;
314	unsigned long size;
315	void **gop_handle = NULL;
316	void **uga_handle = NULL;
317
318	si = &boot_params->screen_info;
319	memset(si, 0, sizeof(*si));
320
321	size = 0;
322	status = efi_bs_call(locate_handle, EFI_LOCATE_BY_PROTOCOL,
323			     &graphics_proto, NULL, &size, gop_handle);
324	if (status == EFI_BUFFER_TOO_SMALL)
325		status = efi_setup_gop(si, &graphics_proto, size);
326
327	if (status != EFI_SUCCESS) {
328		size = 0;
329		status = efi_bs_call(locate_handle, EFI_LOCATE_BY_PROTOCOL,
330				     &uga_proto, NULL, &size, uga_handle);
331		if (status == EFI_BUFFER_TOO_SMALL)
332			setup_uga(si, &uga_proto, size);
333	}
334}
335
336
337static void __noreturn efi_exit(efi_handle_t handle, efi_status_t status)
338{
339	efi_bs_call(exit, handle, status, 0, NULL);
340	for(;;)
341		asm("hlt");
342}
343
344void startup_32(struct boot_params *boot_params);
345
346void __noreturn efi_stub_entry(efi_handle_t handle,
347			       efi_system_table_t *sys_table_arg,
348			       struct boot_params *boot_params);
349
350/*
351 * Because the x86 boot code expects to be passed a boot_params we
352 * need to create one ourselves (usually the bootloader would create
353 * one for us).
354 */
355efi_status_t __efiapi efi_pe_entry(efi_handle_t handle,
356				   efi_system_table_t *sys_table_arg)
357{
358	struct boot_params *boot_params;
359	struct setup_header *hdr;
360	void *image_base;
361	efi_guid_t proto = LOADED_IMAGE_PROTOCOL_GUID;
362	int options_size = 0;
363	efi_status_t status;
364	char *cmdline_ptr;
365
366	efi_system_table = sys_table_arg;
367
368	/* Check if we were booted by the EFI firmware */
369	if (efi_system_table->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE)
370		efi_exit(handle, EFI_INVALID_PARAMETER);
371
372	status = efi_bs_call(handle_protocol, handle, &proto, (void **)&image);
373	if (status != EFI_SUCCESS) {
374		efi_err("Failed to get handle for LOADED_IMAGE_PROTOCOL\n");
375		efi_exit(handle, status);
376	}
377
378	image_base = efi_table_attr(image, image_base);
379	image_offset = (void *)startup_32 - image_base;
380
381	status = efi_allocate_pages(sizeof(struct boot_params),
382				    (unsigned long *)&boot_params, ULONG_MAX);
383	if (status != EFI_SUCCESS) {
384		efi_err("Failed to allocate lowmem for boot params\n");
385		efi_exit(handle, status);
386	}
387
388	memset(boot_params, 0x0, sizeof(struct boot_params));
389
390	hdr = &boot_params->hdr;
391
392	/* Copy the setup header from the second sector to boot_params */
393	memcpy(&hdr->jump, image_base + 512,
394	       sizeof(struct setup_header) - offsetof(struct setup_header, jump));
395
396	/*
397	 * Fill out some of the header fields ourselves because the
398	 * EFI firmware loader doesn't load the first sector.
399	 */
400	hdr->root_flags	= 1;
401	hdr->vid_mode	= 0xffff;
402	hdr->boot_flag	= 0xAA55;
403
404	hdr->type_of_loader = 0x21;
405
406	/* Convert unicode cmdline to ascii */
407	cmdline_ptr = efi_convert_cmdline(image, &options_size);
408	if (!cmdline_ptr)
409		goto fail;
410
411	efi_set_u64_split((unsigned long)cmdline_ptr,
412			  &hdr->cmd_line_ptr, &boot_params->ext_cmd_line_ptr);
413
414	hdr->ramdisk_image = 0;
415	hdr->ramdisk_size = 0;
416
417	efi_stub_entry(handle, sys_table_arg, boot_params);
418	/* not reached */
419
420fail:
421	efi_free(sizeof(struct boot_params), (unsigned long)boot_params);
422
423	efi_exit(handle, status);
424}
425
426static void add_e820ext(struct boot_params *params,
427			struct setup_data *e820ext, u32 nr_entries)
428{
429	struct setup_data *data;
430
431	e820ext->type = SETUP_E820_EXT;
432	e820ext->len  = nr_entries * sizeof(struct boot_e820_entry);
433	e820ext->next = 0;
434
435	data = (struct setup_data *)(unsigned long)params->hdr.setup_data;
436
437	while (data && data->next)
438		data = (struct setup_data *)(unsigned long)data->next;
439
440	if (data)
441		data->next = (unsigned long)e820ext;
442	else
443		params->hdr.setup_data = (unsigned long)e820ext;
444}
445
446static efi_status_t
447setup_e820(struct boot_params *params, struct setup_data *e820ext, u32 e820ext_size)
448{
449	struct boot_e820_entry *entry = params->e820_table;
450	struct efi_info *efi = &params->efi_info;
451	struct boot_e820_entry *prev = NULL;
452	u32 nr_entries;
453	u32 nr_desc;
454	int i;
455
456	nr_entries = 0;
457	nr_desc = efi->efi_memmap_size / efi->efi_memdesc_size;
458
459	for (i = 0; i < nr_desc; i++) {
460		efi_memory_desc_t *d;
461		unsigned int e820_type = 0;
462		unsigned long m = efi->efi_memmap;
463
464#ifdef CONFIG_X86_64
465		m |= (u64)efi->efi_memmap_hi << 32;
466#endif
467
468		d = efi_early_memdesc_ptr(m, efi->efi_memdesc_size, i);
469		switch (d->type) {
470		case EFI_RESERVED_TYPE:
471		case EFI_RUNTIME_SERVICES_CODE:
472		case EFI_RUNTIME_SERVICES_DATA:
473		case EFI_MEMORY_MAPPED_IO:
474		case EFI_MEMORY_MAPPED_IO_PORT_SPACE:
475		case EFI_PAL_CODE:
476			e820_type = E820_TYPE_RESERVED;
477			break;
478
479		case EFI_UNUSABLE_MEMORY:
480			e820_type = E820_TYPE_UNUSABLE;
481			break;
482
483		case EFI_ACPI_RECLAIM_MEMORY:
484			e820_type = E820_TYPE_ACPI;
485			break;
486
487		case EFI_LOADER_CODE:
488		case EFI_LOADER_DATA:
489		case EFI_BOOT_SERVICES_CODE:
490		case EFI_BOOT_SERVICES_DATA:
491		case EFI_CONVENTIONAL_MEMORY:
492			if (efi_soft_reserve_enabled() &&
493			    (d->attribute & EFI_MEMORY_SP))
494				e820_type = E820_TYPE_SOFT_RESERVED;
495			else
496				e820_type = E820_TYPE_RAM;
497			break;
498
499		case EFI_ACPI_MEMORY_NVS:
500			e820_type = E820_TYPE_NVS;
501			break;
502
503		case EFI_PERSISTENT_MEMORY:
504			e820_type = E820_TYPE_PMEM;
505			break;
506
507		default:
508			continue;
509		}
510
511		/* Merge adjacent mappings */
512		if (prev && prev->type == e820_type &&
513		    (prev->addr + prev->size) == d->phys_addr) {
514			prev->size += d->num_pages << 12;
515			continue;
516		}
517
518		if (nr_entries == ARRAY_SIZE(params->e820_table)) {
519			u32 need = (nr_desc - i) * sizeof(struct e820_entry) +
520				   sizeof(struct setup_data);
521
522			if (!e820ext || e820ext_size < need)
523				return EFI_BUFFER_TOO_SMALL;
524
525			/* boot_params map full, switch to e820 extended */
526			entry = (struct boot_e820_entry *)e820ext->data;
527		}
528
529		entry->addr = d->phys_addr;
530		entry->size = d->num_pages << PAGE_SHIFT;
531		entry->type = e820_type;
532		prev = entry++;
533		nr_entries++;
534	}
535
536	if (nr_entries > ARRAY_SIZE(params->e820_table)) {
537		u32 nr_e820ext = nr_entries - ARRAY_SIZE(params->e820_table);
538
539		add_e820ext(params, e820ext, nr_e820ext);
540		nr_entries -= nr_e820ext;
541	}
542
543	params->e820_entries = (u8)nr_entries;
544
545	return EFI_SUCCESS;
546}
547
548static efi_status_t alloc_e820ext(u32 nr_desc, struct setup_data **e820ext,
549				  u32 *e820ext_size)
550{
551	efi_status_t status;
552	unsigned long size;
553
554	size = sizeof(struct setup_data) +
555		sizeof(struct e820_entry) * nr_desc;
556
557	if (*e820ext) {
558		efi_bs_call(free_pool, *e820ext);
559		*e820ext = NULL;
560		*e820ext_size = 0;
561	}
562
563	status = efi_bs_call(allocate_pool, EFI_LOADER_DATA, size,
564			     (void **)e820ext);
565	if (status == EFI_SUCCESS)
566		*e820ext_size = size;
567
568	return status;
569}
570
571static efi_status_t allocate_e820(struct boot_params *params,
572				  struct setup_data **e820ext,
573				  u32 *e820ext_size)
574{
575	unsigned long map_size, desc_size, map_key;
576	efi_status_t status;
577	__u32 nr_desc, desc_version;
578
579	/* Only need the size of the mem map and size of each mem descriptor */
580	map_size = 0;
581	status = efi_bs_call(get_memory_map, &map_size, NULL, &map_key,
582			     &desc_size, &desc_version);
583	if (status != EFI_BUFFER_TOO_SMALL)
584		return (status != EFI_SUCCESS) ? status : EFI_UNSUPPORTED;
585
586	nr_desc = map_size / desc_size + EFI_MMAP_NR_SLACK_SLOTS;
587
588	if (nr_desc > ARRAY_SIZE(params->e820_table)) {
589		u32 nr_e820ext = nr_desc - ARRAY_SIZE(params->e820_table);
590
591		status = alloc_e820ext(nr_e820ext, e820ext, e820ext_size);
592		if (status != EFI_SUCCESS)
593			return status;
594	}
595
596	return EFI_SUCCESS;
597}
598
599struct exit_boot_struct {
600	struct boot_params	*boot_params;
601	struct efi_info		*efi;
602};
603
604static efi_status_t exit_boot_func(struct efi_boot_memmap *map,
605				   void *priv)
606{
607	const char *signature;
608	struct exit_boot_struct *p = priv;
609
610	signature = efi_is_64bit() ? EFI64_LOADER_SIGNATURE
611				   : EFI32_LOADER_SIGNATURE;
612	memcpy(&p->efi->efi_loader_signature, signature, sizeof(__u32));
613
614	efi_set_u64_split((unsigned long)efi_system_table,
615			  &p->efi->efi_systab, &p->efi->efi_systab_hi);
616	p->efi->efi_memdesc_size	= *map->desc_size;
617	p->efi->efi_memdesc_version	= *map->desc_ver;
618	efi_set_u64_split((unsigned long)*map->map,
619			  &p->efi->efi_memmap, &p->efi->efi_memmap_hi);
620	p->efi->efi_memmap_size		= *map->map_size;
621
622	return EFI_SUCCESS;
623}
624
625static efi_status_t exit_boot(struct boot_params *boot_params, void *handle)
626{
627	unsigned long map_sz, key, desc_size, buff_size;
628	efi_memory_desc_t *mem_map;
629	struct setup_data *e820ext = NULL;
630	__u32 e820ext_size = 0;
631	efi_status_t status;
632	__u32 desc_version;
633	struct efi_boot_memmap map;
634	struct exit_boot_struct priv;
635
636	map.map			= &mem_map;
637	map.map_size		= &map_sz;
638	map.desc_size		= &desc_size;
639	map.desc_ver		= &desc_version;
640	map.key_ptr		= &key;
641	map.buff_size		= &buff_size;
642	priv.boot_params	= boot_params;
643	priv.efi		= &boot_params->efi_info;
644
645	status = allocate_e820(boot_params, &e820ext, &e820ext_size);
646	if (status != EFI_SUCCESS)
647		return status;
648
649	/* Might as well exit boot services now */
650	status = efi_exit_boot_services(handle, &map, &priv, exit_boot_func);
651	if (status != EFI_SUCCESS)
652		return status;
653
654	/* Historic? */
655	boot_params->alt_mem_k	= 32 * 1024;
656
657	status = setup_e820(boot_params, e820ext, e820ext_size);
658	if (status != EFI_SUCCESS)
659		return status;
660
661	return EFI_SUCCESS;
662}
663
664/*
665 * On success, we return the address of startup_32, which has potentially been
666 * relocated by efi_relocate_kernel.
667 * On failure, we exit to the firmware via efi_exit instead of returning.
668 */
669unsigned long efi_main(efi_handle_t handle,
670			     efi_system_table_t *sys_table_arg,
671			     struct boot_params *boot_params)
672{
673	unsigned long bzimage_addr = (unsigned long)startup_32;
674	unsigned long buffer_start, buffer_end;
675	struct setup_header *hdr = &boot_params->hdr;
676	efi_status_t status;
677
678	efi_system_table = sys_table_arg;
679
680	/* Check if we were booted by the EFI firmware */
681	if (efi_system_table->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE)
682		efi_exit(handle, EFI_INVALID_PARAMETER);
683
684	/*
685	 * If the kernel isn't already loaded at a suitable address,
686	 * relocate it.
687	 *
688	 * It must be loaded above LOAD_PHYSICAL_ADDR.
689	 *
690	 * The maximum address for 64-bit is 1 << 46 for 4-level paging. This
691	 * is defined as the macro MAXMEM, but unfortunately that is not a
692	 * compile-time constant if 5-level paging is configured, so we instead
693	 * define our own macro for use here.
694	 *
695	 * For 32-bit, the maximum address is complicated to figure out, for
696	 * now use KERNEL_IMAGE_SIZE, which will be 512MiB, the same as what
697	 * KASLR uses.
698	 *
699	 * Also relocate it if image_offset is zero, i.e. the kernel wasn't
700	 * loaded by LoadImage, but rather by a bootloader that called the
701	 * handover entry. The reason we must always relocate in this case is
702	 * to handle the case of systemd-boot booting a unified kernel image,
703	 * which is a PE executable that contains the bzImage and an initrd as
704	 * COFF sections. The initrd section is placed after the bzImage
705	 * without ensuring that there are at least init_size bytes available
706	 * for the bzImage, and thus the compressed kernel's startup code may
707	 * overwrite the initrd unless it is moved out of the way.
708	 */
709
710	buffer_start = ALIGN(bzimage_addr - image_offset,
711			     hdr->kernel_alignment);
712	buffer_end = buffer_start + hdr->init_size;
713
714	if ((buffer_start < LOAD_PHYSICAL_ADDR)				     ||
715	    (IS_ENABLED(CONFIG_X86_32) && buffer_end > KERNEL_IMAGE_SIZE)    ||
716	    (IS_ENABLED(CONFIG_X86_64) && buffer_end > MAXMEM_X86_64_4LEVEL) ||
717	    (image_offset == 0)) {
718		status = efi_relocate_kernel(&bzimage_addr,
719					     hdr->init_size, hdr->init_size,
720					     hdr->pref_address,
721					     hdr->kernel_alignment,
722					     LOAD_PHYSICAL_ADDR);
723		if (status != EFI_SUCCESS) {
724			efi_err("efi_relocate_kernel() failed!\n");
725			goto fail;
726		}
727		/*
728		 * Now that we've copied the kernel elsewhere, we no longer
729		 * have a set up block before startup_32(), so reset image_offset
730		 * to zero in case it was set earlier.
731		 */
732		image_offset = 0;
733	}
734
735#ifdef CONFIG_CMDLINE_BOOL
736	status = efi_parse_options(CONFIG_CMDLINE);
737	if (status != EFI_SUCCESS) {
738		efi_err("Failed to parse options\n");
739		goto fail;
740	}
741#endif
742	if (!IS_ENABLED(CONFIG_CMDLINE_OVERRIDE)) {
743		unsigned long cmdline_paddr = ((u64)hdr->cmd_line_ptr |
744					       ((u64)boot_params->ext_cmd_line_ptr << 32));
745		status = efi_parse_options((char *)cmdline_paddr);
746		if (status != EFI_SUCCESS) {
747			efi_err("Failed to parse options\n");
748			goto fail;
749		}
750	}
751
752	/*
753	 * At this point, an initrd may already have been loaded by the
754	 * bootloader and passed via bootparams. We permit an initrd loaded
755	 * from the LINUX_EFI_INITRD_MEDIA_GUID device path to supersede it.
756	 *
757	 * If the device path is not present, any command-line initrd=
758	 * arguments will be processed only if image is not NULL, which will be
759	 * the case only if we were loaded via the PE entry point.
760	 */
761	if (!efi_noinitrd) {
762		unsigned long addr, size;
763
764		status = efi_load_initrd(image, &addr, &size,
765					 hdr->initrd_addr_max, ULONG_MAX);
766
767		if (status != EFI_SUCCESS) {
768			efi_err("Failed to load initrd!\n");
769			goto fail;
770		}
771		if (size > 0) {
772			efi_set_u64_split(addr, &hdr->ramdisk_image,
773					  &boot_params->ext_ramdisk_image);
774			efi_set_u64_split(size, &hdr->ramdisk_size,
775					  &boot_params->ext_ramdisk_size);
776		}
777	}
778
779	/*
780	 * If the boot loader gave us a value for secure_boot then we use that,
781	 * otherwise we ask the BIOS.
782	 */
783	if (boot_params->secure_boot == efi_secureboot_mode_unset)
784		boot_params->secure_boot = efi_get_secureboot();
785
786	/* Ask the firmware to clear memory on unclean shutdown */
787	efi_enable_reset_attack_mitigation();
788
789	efi_random_get_seed();
790
791	efi_retrieve_tpm2_eventlog();
792
793	setup_graphics(boot_params);
794
795	setup_efi_pci(boot_params);
796
797	setup_quirks(boot_params);
798
799	status = exit_boot(boot_params, handle);
800	if (status != EFI_SUCCESS) {
801		efi_err("exit_boot() failed!\n");
802		goto fail;
803	}
804
805	return bzimage_addr;
806fail:
807	efi_err("efi_main() failed!\n");
808
809	efi_exit(handle, status);
810}