Merge branch 'x86-efi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip (0a2fe19c) · Commits · e / devices / android_kernel_oneplus_sm7250

Documentation/x86/boot.txt

+41 −0

Original line number	Original line	Diff line number	Diff line
	@@ -54,6 +54,9 @@ Protocol 2.10: (Kernel 2.6.31) Added a protocol for relaxed alignment
	beyond the kernel_alignment added, new init_size and		beyond the kernel_alignment added, new init_size and
	pref_address fields. Added extended boot loader IDs.		pref_address fields. Added extended boot loader IDs.

			Protocol 2.11: (Kernel 3.6) Added a field for offset of EFI handover
			protocol entry point.

	**** MEMORY LAYOUT		**** MEMORY LAYOUT

	The traditional memory map for the kernel loader, used for Image or		The traditional memory map for the kernel loader, used for Image or
	@@ -189,6 +192,7 @@ Offset Proto Name Meaning
	of struct setup_data		of struct setup_data
	0258/8 2.10+ pref_address Preferred loading address		0258/8 2.10+ pref_address Preferred loading address
	0260/4 2.10+ init_size Linear memory required during initialization		0260/4 2.10+ init_size Linear memory required during initialization
			0264/4 2.11+ handover_offset Offset of handover entry point

	(1) For backwards compatibility, if the setup_sects field contains 0, the		(1) For backwards compatibility, if the setup_sects field contains 0, the
	real value is 4.		real value is 4.
	@@ -693,6 +697,16 @@ Offset/size: 0x260/4
	else		else
	runtime_start = pref_address		runtime_start = pref_address

			Field name: handover_offset
			Type: read
			Offset/size: 0x264/4

			This field is the offset from the beginning of the kernel image to
			the EFI handover protocol entry point. Boot loaders using the EFI
			handover protocol to boot the kernel should jump to this offset.

			See EFI HANDOVER PROTOCOL below for more details.


	**** THE IMAGE CHECKSUM		**** THE IMAGE CHECKSUM

	@@ -1013,3 +1027,30 @@ segment; __BOOS_CS must have execute/read permission, and __BOOT_DS
	must have read/write permission; CS must be __BOOT_CS and DS, ES, SS		must have read/write permission; CS must be __BOOT_CS and DS, ES, SS
	must be __BOOT_DS; interrupt must be disabled; %esi must hold the base		must be __BOOT_DS; interrupt must be disabled; %esi must hold the base
	address of the struct boot_params; %ebp, %edi and %ebx must be zero.		address of the struct boot_params; %ebp, %edi and %ebx must be zero.

			**** EFI HANDOVER PROTOCOL

			This protocol allows boot loaders to defer initialisation to the EFI
			boot stub. The boot loader is required to load the kernel/initrd(s)
			from the boot media and jump to the EFI handover protocol entry point
			which is hdr->handover_offset bytes from the beginning of
			startup_{32,64}.

			The function prototype for the handover entry point looks like this,

			efi_main(void handle, efi_system_table_t table, struct boot_params *bp)

			'handle' is the EFI image handle passed to the boot loader by the EFI
			firmware, 'table' is the EFI system table - these are the first two
			arguments of the "handoff state" as described in section 2.3 of the
			UEFI specification. 'bp' is the boot loader-allocated boot params.

			The boot loader must fill out the following fields in bp,

			o hdr.code32_start
			o hdr.cmd_line_ptr
			o hdr.cmdline_size
			o hdr.ramdisk_image (if applicable)
			o hdr.ramdisk_size (if applicable)

			All other fields should be zero.

arch/x86/boot/compressed/eboot.c

+120 −78

Original line number	Original line	Diff line number	Diff line
	@@ -729,32 +729,68 @@ static efi_status_t handle_ramdisks(efi_loaded_image_t *image,
	* need to create one ourselves (usually the bootloader would create		* need to create one ourselves (usually the bootloader would create
	* one for us).		* one for us).
	*/		*/
	static efi_status_t make_boot_params(struct boot_params *boot_params,		struct boot_params make_boot_params(void handle, efi_system_table_t *_table)
	efi_loaded_image_t *image,
	void *handle)
	{		{
	struct efi_info *efi = &boot_params->efi_info;		struct boot_params *boot_params;
	struct apm_bios_info *bi = &boot_params->apm_bios_info;		struct sys_desc_table *sdt;
	struct sys_desc_table *sdt = &boot_params->sys_desc_table;		struct apm_bios_info *bi;
	struct e820entry *e820_map = &boot_params->e820_map[0];		struct setup_header *hdr;
	struct e820entry *prev = NULL;		struct efi_info *efi;
	struct setup_header *hdr = &boot_params->hdr;		efi_loaded_image_t *image;
	unsigned long size, key, desc_size, _size;		void *options;
	efi_memory_desc_t *mem_map;		u32 load_options_size;
	void *options = image->load_options;		efi_guid_t proto = LOADED_IMAGE_PROTOCOL_GUID;
	u32 load_options_size = image->load_options_size / 2; /* ASCII */
	int options_size = 0;		int options_size = 0;
	efi_status_t status;		efi_status_t status;
	__u32 desc_version;
	unsigned long cmdline;		unsigned long cmdline;
	u8 nr_entries;
	u16 *s2;		u16 *s2;
	u8 *s1;		u8 *s1;
	int i;		int i;

			sys_table = _table;

			/* Check if we were booted by the EFI firmware */
			if (sys_table->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE)
			return NULL;

			status = efi_call_phys3(sys_table->boottime->handle_protocol,
			handle, &proto, (void *)&image);
			if (status != EFI_SUCCESS) {
			efi_printk("Failed to get handle for LOADED_IMAGE_PROTOCOL\n");
			return NULL;
			}

			status = low_alloc(0x4000, 1, (unsigned long *)&boot_params);
			if (status != EFI_SUCCESS) {
			efi_printk("Failed to alloc lowmem for boot params\n");
			return NULL;
			}

			memset(boot_params, 0x0, 0x4000);

			hdr = &boot_params->hdr;
			efi = &boot_params->efi_info;
			bi = &boot_params->apm_bios_info;
			sdt = &boot_params->sys_desc_table;

			/* Copy the second sector to boot_params */
			memcpy(&hdr->jump, image->image_base + 512, 512);

			/*
			* Fill out some of the header fields ourselves because the
			* EFI firmware loader doesn't load the first sector.
			*/
			hdr->root_flags = 1;
			hdr->vid_mode = 0xffff;
			hdr->boot_flag = 0xAA55;

			hdr->code32_start = (__u64)(unsigned long)image->image_base;

	hdr->type_of_loader = 0x21;		hdr->type_of_loader = 0x21;

	/* Convert unicode cmdline to ascii */		/* Convert unicode cmdline to ascii */
			options = image->load_options;
			load_options_size = image->load_options_size / 2; /* ASCII */
	cmdline = 0;		cmdline = 0;
	s2 = (u16 *)options;		s2 = (u16 *)options;

	@@ -791,18 +827,36 @@ static efi_status_t make_boot_params(struct boot_params *boot_params,
	hdr->ramdisk_image = 0;		hdr->ramdisk_image = 0;
	hdr->ramdisk_size = 0;		hdr->ramdisk_size = 0;

	status = handle_ramdisks(image, hdr);
	if (status != EFI_SUCCESS)
	goto free_cmdline;

	setup_graphics(boot_params);

	/* Clear APM BIOS info */		/* Clear APM BIOS info */
	memset(bi, 0, sizeof(*bi));		memset(bi, 0, sizeof(*bi));

	memset(sdt, 0, sizeof(*sdt));		memset(sdt, 0, sizeof(*sdt));

	memcpy(&efi->efi_loader_signature, EFI_LOADER_SIGNATURE, sizeof(__u32));		status = handle_ramdisks(image, hdr);
			if (status != EFI_SUCCESS)
			goto fail2;

			return boot_params;
			fail2:
			if (options_size)
			low_free(options_size, hdr->cmd_line_ptr);
			fail:
			low_free(0x4000, (unsigned long)boot_params);
			return NULL;
			}

			static efi_status_t exit_boot(struct boot_params *boot_params,
			void *handle)
			{
			struct efi_info *efi = &boot_params->efi_info;
			struct e820entry *e820_map = &boot_params->e820_map[0];
			struct e820entry *prev = NULL;
			unsigned long size, key, desc_size, _size;
			efi_memory_desc_t *mem_map;
			efi_status_t status;
			__u32 desc_version;
			u8 nr_entries;
			int i;

	size = sizeof(mem_map) 32;		size = sizeof(mem_map) 32;

	@@ -811,7 +865,7 @@ static efi_status_t make_boot_params(struct boot_params *boot_params,
	_size = size;		_size = size;
	status = low_alloc(size, 1, (unsigned long *)&mem_map);		status = low_alloc(size, 1, (unsigned long *)&mem_map);
	if (status != EFI_SUCCESS)		if (status != EFI_SUCCESS)
	goto free_cmdline;		return status;

	status = efi_call_phys5(sys_table->boottime->get_memory_map, &size,		status = efi_call_phys5(sys_table->boottime->get_memory_map, &size,
	mem_map, &key, &desc_size, &desc_version);		mem_map, &key, &desc_size, &desc_version);
	@@ -823,6 +877,7 @@ static efi_status_t make_boot_params(struct boot_params *boot_params,
	if (status != EFI_SUCCESS)		if (status != EFI_SUCCESS)
	goto free_mem_map;		goto free_mem_map;

			memcpy(&efi->efi_loader_signature, EFI_LOADER_SIGNATURE, sizeof(__u32));
	efi->efi_systab = (unsigned long)sys_table;		efi->efi_systab = (unsigned long)sys_table;
	efi->efi_memdesc_size = desc_size;		efi->efi_memdesc_size = desc_size;
	efi->efi_memdesc_version = desc_version;		efi->efi_memdesc_version = desc_version;
	@@ -906,61 +961,13 @@ static efi_status_t make_boot_params(struct boot_params *boot_params,

	free_mem_map:		free_mem_map:
	low_free(_size, (unsigned long)mem_map);		low_free(_size, (unsigned long)mem_map);
	free_cmdline:
	if (options_size)
	low_free(options_size, hdr->cmd_line_ptr);
	fail:
	return status;		return status;
	}		}

	/*		static efi_status_t relocate_kernel(struct setup_header *hdr)
	* On success we return a pointer to a boot_params structure, and NULL
	* on failure.
	*/
	struct boot_params efi_main(void handle, efi_system_table_t *_table)
	{		{
	struct boot_params *boot_params;
	unsigned long start, nr_pages;		unsigned long start, nr_pages;
	struct desc_ptr gdt, idt;
	efi_loaded_image_t *image;
	struct setup_header *hdr;
	efi_status_t status;		efi_status_t status;
	efi_guid_t proto = LOADED_IMAGE_PROTOCOL_GUID;
	struct desc_struct *desc;

	sys_table = _table;

	/* Check if we were booted by the EFI firmware */
	if (sys_table->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE)
	goto fail;

	status = efi_call_phys3(sys_table->boottime->handle_protocol,
	handle, &proto, (void *)&image);
	if (status != EFI_SUCCESS) {
	efi_printk("Failed to get handle for LOADED_IMAGE_PROTOCOL\n");
	goto fail;
	}

	status = low_alloc(0x4000, 1, (unsigned long *)&boot_params);
	if (status != EFI_SUCCESS) {
	efi_printk("Failed to alloc lowmem for boot params\n");
	goto fail;
	}

	memset(boot_params, 0x0, 0x4000);

	hdr = &boot_params->hdr;

	/* Copy the second sector to boot_params */
	memcpy(&hdr->jump, image->image_base + 512, 512);

	/*
	* Fill out some of the header fields ourselves because the
	* EFI firmware loader doesn't load the first sector.
	*/
	hdr->root_flags = 1;
	hdr->vid_mode = 0xffff;
	hdr->boot_flag = 0xAA55;

	/*		/*
	* The EFI firmware loader could have placed the kernel image		* The EFI firmware loader could have placed the kernel image
	@@ -978,16 +985,40 @@ struct boot_params efi_main(void handle, efi_system_table_t *_table)
	if (status != EFI_SUCCESS) {		if (status != EFI_SUCCESS) {
	status = low_alloc(hdr->init_size, hdr->kernel_alignment,		status = low_alloc(hdr->init_size, hdr->kernel_alignment,
	&start);		&start);
	if (status != EFI_SUCCESS) {		if (status != EFI_SUCCESS)
	efi_printk("Failed to alloc mem for kernel\n");		efi_printk("Failed to alloc mem for kernel\n");
	goto fail;
	}
	}		}

			if (status == EFI_SUCCESS)
			memcpy((void )start, (void )(unsigned long)hdr->code32_start,
			hdr->init_size);

			hdr->pref_address = hdr->code32_start;
	hdr->code32_start = (__u32)start;		hdr->code32_start = (__u32)start;
	hdr->pref_address = (__u64)(unsigned long)image->image_base;

	memcpy((void *)start, image->image_base, image->image_size);		return status;
			}

			/*
			* On success we return a pointer to a boot_params structure, and NULL
			* on failure.
			*/
			struct boot_params efi_main(void handle, efi_system_table_t *_table,
			struct boot_params *boot_params)
			{
			struct desc_ptr gdt, idt;
			efi_loaded_image_t *image;
			struct setup_header *hdr = &boot_params->hdr;
			efi_status_t status;
			struct desc_struct *desc;

			sys_table = _table;

			/* Check if we were booted by the EFI firmware */
			if (sys_table->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE)
			goto fail;

			setup_graphics(boot_params);

	status = efi_call_phys3(sys_table->boottime->allocate_pool,		status = efi_call_phys3(sys_table->boottime->allocate_pool,
	EFI_LOADER_DATA, sizeof(*gdt),		EFI_LOADER_DATA, sizeof(*gdt),
	@@ -1015,7 +1046,18 @@ struct boot_params efi_main(void handle, efi_system_table_t *_table)
	idt->size = 0;		idt->size = 0;
	idt->address = 0;		idt->address = 0;

	status = make_boot_params(boot_params, image, handle);		/*
			* If the kernel isn't already loaded at the preferred load
			* address, relocate it.
			*/
			if (hdr->pref_address != hdr->code32_start) {
			status = relocate_kernel(hdr);

			if (status != EFI_SUCCESS)
			goto fail;
			}

			status = exit_boot(boot_params, handle);
	if (status != EFI_SUCCESS)		if (status != EFI_SUCCESS)
	goto fail;		goto fail;

arch/x86/boot/compressed/head_32.S

+10 −0

Original line number	Original line	Diff line number	Diff line
	@@ -42,6 +42,16 @@ ENTRY(startup_32)
	*/		*/
	add $0x4, %esp		add $0x4, %esp

			call make_boot_params
			cmpl $0, %eax
			je 1f
			movl 0x4(%esp), %esi
			movl (%esp), %ecx
			pushl %eax
			pushl %esi
			pushl %ecx

			.org 0x30,0x90
	call efi_main		call efi_main
	cmpl $0, %eax		cmpl $0, %eax
	movl %eax, %esi		movl %eax, %esi

arch/x86/boot/compressed/head_64.S

+10 −0

Original line number	Original line	Diff line number	Diff line
	@@ -209,6 +209,16 @@ ENTRY(startup_64)
	.org 0x210		.org 0x210
	mov %rcx, %rdi		mov %rcx, %rdi
	mov %rdx, %rsi		mov %rdx, %rsi
			pushq %rdi
			pushq %rsi
			call make_boot_params
			cmpq $0,%rax
			je 1f
			mov %rax, %rdx
			popq %rsi
			popq %rdi

			.org 0x230,0x90
	call efi_main		call efi_main
	movq %rax,%rsi		movq %rax,%rsi
	cmpq $0,%rax		cmpq $0,%rax

arch/x86/boot/header.S

+3 −1

Original line number	Original line	Diff line number	Diff line
	@@ -283,7 +283,7 @@ _start:
	# Part 2 of the header, from the old setup.S		# Part 2 of the header, from the old setup.S

	.ascii "HdrS" # header signature		.ascii "HdrS" # header signature
	.word 0x020a # header version number (>= 0x0105)		.word 0x020b # header version number (>= 0x0105)
	# or else old loadlin-1.5 will fail)		# or else old loadlin-1.5 will fail)
	.globl realmode_swtch		.globl realmode_swtch
	realmode_swtch: .word 0, 0 # default_switch, SETUPSEG		realmode_swtch: .word 0, 0 # default_switch, SETUPSEG
	@@ -401,6 +401,8 @@ pref_address: .quad LOAD_PHYSICAL_ADDR # preferred load addr
	#define INIT_SIZE VO_INIT_SIZE		#define INIT_SIZE VO_INIT_SIZE
	#endif		#endif
	init_size: .long INIT_SIZE # kernel initialization size		init_size: .long INIT_SIZE # kernel initialization size
			handover_offset: .long 0x30 # offset to the handover
			# protocol entry point

	# End of setup header #####################################################		# End of setup header #####################################################