/* * EFI stub implementation that is shared by arm and arm64 architectures. * This should be #included by the EFI stub implementation files. * * Copyright (C) 2013,2014 Linaro Limited * Roy Franz * * This file is part of the Linux kernel, and is made available under the * terms of the GNU General Public License version 2. * */ static int __init efi_secureboot_enabled(efi_system_table_t *sys_table_arg) { static efi_guid_t const var_guid __initconst = EFI_GLOBAL_VARIABLE_GUID; static efi_char16_t const var_name[] __initconst = { 'S', 'e', 'c', 'u', 'r', 'e', 'B', 'o', 'o', 't', 0 }; efi_get_variable_t *f_getvar = sys_table_arg->runtime->get_variable; unsigned long size = sizeof(u8); efi_status_t status; u8 val; status = f_getvar((efi_char16_t *)var_name, (efi_guid_t *)&var_guid, NULL, &size, &val); switch (status) { case EFI_SUCCESS: return val; case EFI_NOT_FOUND: return 0; default: return 1; } } static efi_status_t efi_open_volume(efi_system_table_t *sys_table_arg, void *__image, void **__fh) { efi_file_io_interface_t *io; efi_loaded_image_t *image = __image; efi_file_handle_t *fh; efi_guid_t fs_proto = EFI_FILE_SYSTEM_GUID; efi_status_t status; void *handle = (void *)(unsigned long)image->device_handle; status = sys_table_arg->boottime->handle_protocol(handle, &fs_proto, (void **)&io); if (status != EFI_SUCCESS) { efi_printk(sys_table_arg, "Failed to handle fs_proto\n"); return status; } status = io->open_volume(io, &fh); if (status != EFI_SUCCESS) efi_printk(sys_table_arg, "Failed to open volume\n"); *__fh = fh; return status; } static efi_status_t efi_file_close(void *handle) { efi_file_handle_t *fh = handle; return fh->close(handle); } static efi_status_t efi_file_read(void *handle, unsigned long *size, void *addr) { efi_file_handle_t *fh = handle; return fh->read(handle, size, addr); } static efi_status_t efi_file_size(efi_system_table_t *sys_table_arg, void *__fh, efi_char16_t *filename_16, void **handle, u64 *file_sz) { efi_file_handle_t *h, *fh = __fh; efi_file_info_t *info; efi_status_t status; efi_guid_t info_guid = EFI_FILE_INFO_ID; unsigned long info_sz; status = fh->open(fh, &h, filename_16, EFI_FILE_MODE_READ, (u64)0); if (status != EFI_SUCCESS) { efi_printk(sys_table_arg, "Failed to open file: "); efi_char16_printk(sys_table_arg, filename_16); efi_printk(sys_table_arg, "\n"); return status; } *handle = h; info_sz = 0; status = h->get_info(h, &info_guid, &info_sz, NULL); if (status != EFI_BUFFER_TOO_SMALL) { efi_printk(sys_table_arg, "Failed to get file info size\n"); return status; } grow: status = sys_table_arg->boottime->allocate_pool(EFI_LOADER_DATA, info_sz, (void **)&info); if (status != EFI_SUCCESS) { efi_printk(sys_table_arg, "Failed to alloc mem for file info\n"); return status; } status = h->get_info(h, &info_guid, &info_sz, info); if (status == EFI_BUFFER_TOO_SMALL) { sys_table_arg->boottime->free_pool(info); goto grow; } *file_sz = info->file_size; sys_table_arg->boottime->free_pool(info); if (status != EFI_SUCCESS) efi_printk(sys_table_arg, "Failed to get initrd info\n"); return status; } static void efi_char16_printk(efi_system_table_t *sys_table_arg, efi_char16_t *str) { struct efi_simple_text_output_protocol *out; out = (struct efi_simple_text_output_protocol *)sys_table_arg->con_out; out->output_string(out, str); } /* * This function handles the architcture specific differences between arm and * arm64 regarding where the kernel image must be loaded and any memory that * must be reserved. On failure it is required to free all * all allocations it has made. */ static efi_status_t handle_kernel_image(efi_system_table_t *sys_table, unsigned long *image_addr, unsigned long *image_size, unsigned long *reserve_addr, unsigned long *reserve_size, unsigned long dram_base, efi_loaded_image_t *image); /* * EFI entry point for the arm/arm64 EFI stubs. This is the entrypoint * that is described in the PE/COFF header. Most of the code is the same * for both archictectures, with the arch-specific code provided in the * handle_kernel_image() function. */ unsigned long __init efi_entry(void *handle, efi_system_table_t *sys_table, unsigned long *image_addr) { efi_loaded_image_t *image; efi_status_t status; unsigned long image_size = 0; unsigned long dram_base; /* addr/point and size pairs for memory management*/ unsigned long initrd_addr; u64 initrd_size = 0; unsigned long fdt_addr = 0; /* Original DTB */ u64 fdt_size = 0; /* We don't get size from configuration table */ char *cmdline_ptr = NULL; int cmdline_size = 0; unsigned long new_fdt_addr; efi_guid_t loaded_image_proto = LOADED_IMAGE_PROTOCOL_GUID; unsigned long reserve_addr = 0; unsigned long reserve_size = 0; /* Check if we were booted by the EFI firmware */ if (sys_table->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE) goto fail; pr_efi(sys_table, "Booting Linux Kernel...\n"); /* * Get a handle to the loaded image protocol. This is used to get * information about the running image, such as size and the command * line. */ status = sys_table->boottime->handle_protocol(handle, &loaded_image_proto, (void *)&image); if (status != EFI_SUCCESS) { pr_efi_err(sys_table, "Failed to get loaded image protocol\n"); goto fail; } dram_base = get_dram_base(sys_table); if (dram_base == EFI_ERROR) { pr_efi_err(sys_table, "Failed to find DRAM base\n"); goto fail; } status = handle_kernel_image(sys_table, image_addr, &image_size, &reserve_addr, &reserve_size, dram_base, image); if (status != EFI_SUCCESS) { pr_efi_err(sys_table, "Failed to relocate kernel\n"); goto fail; } /* * Get the command line from EFI, using the LOADED_IMAGE * protocol. We are going to copy the command line into the * device tree, so this can be allocated anywhere. */ cmdline_ptr = efi_convert_cmdline(sys_table, image, &cmdline_size); if (!cmdline_ptr) { pr_efi_err(sys_table, "getting command line via LOADED_IMAGE_PROTOCOL\n"); goto fail_free_image; } /* * Unauthenticated device tree data is a security hazard, so * ignore 'dtb=' unless UEFI Secure Boot is disabled. */ if (efi_secureboot_enabled(sys_table)) { pr_efi(sys_table, "UEFI Secure Boot is enabled.\n"); } else { status = handle_cmdline_files(sys_table, image, cmdline_ptr, "dtb=", ~0UL, (unsigned long *)&fdt_addr, (unsigned long *)&fdt_size); if (status != EFI_SUCCESS) { pr_efi_err(sys_table, "Failed to load device tree!\n"); goto fail_free_cmdline; } } if (!fdt_addr) /* Look for a device tree configuration table entry. */ fdt_addr = (uintptr_t)get_fdt(sys_table); status = handle_cmdline_files(sys_table, image, cmdline_ptr, "initrd=", dram_base + SZ_512M, (unsigned long *)&initrd_addr, (unsigned long *)&initrd_size); if (status != EFI_SUCCESS) pr_efi_err(sys_table, "Failed initrd from command line!\n"); new_fdt_addr = fdt_addr; status = allocate_new_fdt_and_exit_boot(sys_table, handle, &new_fdt_addr, dram_base + MAX_FDT_OFFSET, initrd_addr, initrd_size, cmdline_ptr, fdt_addr, fdt_size); /* * If all went well, we need to return the FDT address to the * calling function so it can be passed to kernel as part of * the kernel boot protocol. */ if (status == EFI_SUCCESS) return new_fdt_addr; pr_efi_err(sys_table, "Failed to update FDT and exit boot services\n"); efi_free(sys_table, initrd_size, initrd_addr); efi_free(sys_table, fdt_size, fdt_addr); fail_free_cmdline: efi_free(sys_table, cmdline_size, (unsigned long)cmdline_ptr); fail_free_image: efi_free(sys_table, image_size, *image_addr); efi_free(sys_table, reserve_size, reserve_addr); fail: return EFI_ERROR; }