projects / linux-2.6-block.git / blame
| Commit | Line | Data |
|---|---|---|
| f84d0275 MS |
1 | /* |
| 2 | * Extensible Firmware Interface | |
| 3 | * | |
| 4 | * Based on Extensible Firmware Interface Specification version 2.4 | |
| 5 | * | |
| 6 | * Copyright (C) 2013, 2014 Linaro Ltd. | |
| 7 | * | |
| 8 | * This program is free software; you can redistribute it and/or modify | |
| 9 | * it under the terms of the GNU General Public License version 2 as | |
| 10 | * published by the Free Software Foundation. | |
| 11 | * | |
| 12 | */ | |
| 13 | ||
| d1ae8c00 | 14 | #include <linux/dmi.h> |
| f84d0275 | 15 | #include <linux/efi.h> |
| e5bc22a4 | 16 | #include <linux/init.h> |
| f84d0275 | 17 | |
| f84d0275 | 18 | #include <asm/efi.h> |
| d1ae8c00 | 19 | |
| 1fd55a9a AB |
20 | /* |
| 21 | * Only regions of type EFI_RUNTIME_SERVICES_CODE need to be | |
| 22 | * executable, everything else can be mapped with the XN bits | |
| 23 | * set. Also take the new (optional) RO/XP bits into account. | |
| 24 | */ | |
| 25 | static __init pteval_t create_mapping_protection(efi_memory_desc_t *md) | |
| f7d92489 | 26 | { |
| 1fd55a9a AB |
27 | u64 attr = md->attribute; |
| 28 | u32 type = md->type; | |
| f7d92489 | 29 | |
| 1fd55a9a AB |
30 | if (type == EFI_MEMORY_MAPPED_IO) |
| 31 | return PROT_DEVICE_nGnRE; | |
| 32 | ||
| 33 | if (WARN_ONCE(!PAGE_ALIGNED(md->phys_addr), | |
| 34 | "UEFI Runtime regions are not aligned to 64 KB -- buggy firmware?")) | |
| 35 | /* | |
| 36 | * If the region is not aligned to the page size of the OS, we | |
| 37 | * can not use strict permissions, since that would also affect | |
| 38 | * the mapping attributes of the adjacent regions. | |
| 39 | */ | |
| 40 | return pgprot_val(PAGE_KERNEL_EXEC); | |
| 41 | ||
| 42 | /* R-- */ | |
| 43 | if ((attr & (EFI_MEMORY_XP | EFI_MEMORY_RO)) == | |
| 44 | (EFI_MEMORY_XP | EFI_MEMORY_RO)) | |
| 45 | return pgprot_val(PAGE_KERNEL_RO); | |
| 46 | ||
| 47 | /* R-X */ | |
| 48 | if (attr & EFI_MEMORY_RO) | |
| 49 | return pgprot_val(PAGE_KERNEL_ROX); | |
| 50 | ||
| 51 | /* RW- */ | |
| 52 | if (attr & EFI_MEMORY_XP || type != EFI_RUNTIME_SERVICES_CODE) | |
| 53 | return pgprot_val(PAGE_KERNEL); | |
| 54 | ||
| 55 | /* RWX */ | |
| 56 | return pgprot_val(PAGE_KERNEL_EXEC); | |
| 57 | } | |
| 58 | ||
| 57fdb89a AB |
59 | /* we will fill this structure from the stub, so don't put it in .bss */ |
| 60 | struct screen_info screen_info __section(.data); | |
| 61 | ||
| 1fd55a9a AB |
62 | int __init efi_create_mapping(struct mm_struct *mm, efi_memory_desc_t *md) |
| 63 | { | |
| 64 | pteval_t prot_val = create_mapping_protection(md); | |
| f7d92489 AB |
65 | |
| 66 | create_pgd_mapping(mm, md->phys_addr, md->virt_addr, | |
| 67 | md->num_pages << EFI_PAGE_SHIFT, | |
| 68 | __pgprot(prot_val | PTE_NG)); | |
| 69 | return 0; | |
| 70 | } | |
| 71 | ||
| d1ae8c00 YL |
72 | static int __init arm64_dmi_init(void) |
| 73 | { | |
| 74 | /* | |
| 75 | * On arm64, DMI depends on UEFI, and dmi_scan_machine() needs to | |
| 76 | * be called early because dmi_id_init(), which is an arch_initcall | |
| 77 | * itself, depends on dmi_scan_machine() having been called already. | |
| 78 | */ | |
| 79 | dmi_scan_machine(); | |
| b07bfaa3 AB |
80 | if (dmi_available) |
| 81 | dmi_set_dump_stack_arch_desc(); | |
| d1ae8c00 YL |
82 | return 0; |
| 83 | } | |
| 84 | core_initcall(arm64_dmi_init); | |
| f3cdfd23 | 85 | |
| 60c0d45a AB |
86 | /* |
| 87 | * UpdateCapsule() depends on the system being shutdown via | |
| 88 | * ResetSystem(). | |
| 89 | */ | |
| 90 | bool efi_poweroff_required(void) | |
| 91 | { | |
| 92 | return efi_enabled(EFI_RUNTIME_SERVICES); | |
| 93 | } |