beyond the kernel_alignment added, new init_size and
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
The traditional memory map for the kernel loader, used for Image or
of struct setup_data
0258/8 2.10+ pref_address Preferred loading address
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
real value is 4.
else
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
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
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.
* need to create one ourselves (usually the bootloader would create
* one for us).
*/
-static efi_status_t make_boot_params(struct boot_params *boot_params,
- efi_loaded_image_t *image,
- void *handle)
+struct boot_params *make_boot_params(void *handle, efi_system_table_t *_table)
{
- struct efi_info *efi = &boot_params->efi_info;
- struct apm_bios_info *bi = &boot_params->apm_bios_info;
- struct sys_desc_table *sdt = &boot_params->sys_desc_table;
- struct e820entry *e820_map = &boot_params->e820_map[0];
- struct e820entry *prev = NULL;
- struct setup_header *hdr = &boot_params->hdr;
- unsigned long size, key, desc_size, _size;
- efi_memory_desc_t *mem_map;
- void *options = image->load_options;
- u32 load_options_size = image->load_options_size / 2; /* ASCII */
+ struct boot_params *boot_params;
+ struct sys_desc_table *sdt;
+ struct apm_bios_info *bi;
+ struct setup_header *hdr;
+ struct efi_info *efi;
+ efi_loaded_image_t *image;
+ void *options;
+ u32 load_options_size;
+ efi_guid_t proto = LOADED_IMAGE_PROTOCOL_GUID;
int options_size = 0;
efi_status_t status;
- __u32 desc_version;
unsigned long cmdline;
- u8 nr_entries;
u16 *s2;
u8 *s1;
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;
/* Convert unicode cmdline to ascii */
+ options = image->load_options;
+ load_options_size = image->load_options_size / 2; /* ASCII */
cmdline = 0;
s2 = (u16 *)options;
hdr->ramdisk_image = 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 */
memset(bi, 0, sizeof(*bi));
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 = size;
status = low_alloc(size, 1, (unsigned long *)&mem_map);
if (status != EFI_SUCCESS)
- goto free_cmdline;
+ return status;
status = efi_call_phys5(sys_table->boottime->get_memory_map, &size,
mem_map, &key, &desc_size, &desc_version);
if (status != EFI_SUCCESS)
goto free_mem_map;
+ memcpy(&efi->efi_loader_signature, EFI_LOADER_SIGNATURE, sizeof(__u32));
efi->efi_systab = (unsigned long)sys_table;
efi->efi_memdesc_size = desc_size;
efi->efi_memdesc_version = desc_version;
free_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;
}
-/*
- * 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)
+static efi_status_t relocate_kernel(struct setup_header *hdr)
{
- struct boot_params *boot_params;
unsigned long start, nr_pages;
- struct desc_ptr *gdt, *idt;
- efi_loaded_image_t *image;
- struct setup_header *hdr;
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
if (status != EFI_SUCCESS) {
status = low_alloc(hdr->init_size, hdr->kernel_alignment,
&start);
- if (status != EFI_SUCCESS) {
+ if (status != EFI_SUCCESS)
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->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,
EFI_LOADER_DATA, sizeof(*gdt),
idt->size = 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)
goto fail;
projects / ~andy / linux / commitdiff