projects / deliverable / linux.git / blame
| Commit | Line | Data |
|---|---|---|
| e5bc22a4 AB |
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 | ||
| 14 | #include <linux/efi.h> | |
| f7d92489 | 15 | #include <linux/io.h> |
| e5bc22a4 AB |
16 | #include <linux/memblock.h> |
| 17 | #include <linux/mm_types.h> | |
| 18 | #include <linux/preempt.h> | |
| 19 | #include <linux/rbtree.h> | |
| 20 | #include <linux/rwsem.h> | |
| 21 | #include <linux/sched.h> | |
| 22 | #include <linux/slab.h> | |
| 23 | #include <linux/spinlock.h> | |
| 24 | ||
| 25 | #include <asm/cacheflush.h> | |
| 26 | #include <asm/efi.h> | |
| e5bc22a4 | 27 | #include <asm/mmu.h> |
| f7d92489 | 28 | #include <asm/pgalloc.h> |
| e5bc22a4 AB |
29 | #include <asm/pgtable.h> |
| 30 | ||
| e5bc22a4 AB |
31 | extern u64 efi_system_table; |
| 32 | ||
| 33 | static struct mm_struct efi_mm = { | |
| 34 | .mm_rb = RB_ROOT, | |
| e5bc22a4 AB |
35 | .mm_users = ATOMIC_INIT(2), |
| 36 | .mm_count = ATOMIC_INIT(1), | |
| 37 | .mmap_sem = __RWSEM_INITIALIZER(efi_mm.mmap_sem), | |
| 38 | .page_table_lock = __SPIN_LOCK_UNLOCKED(efi_mm.page_table_lock), | |
| 39 | .mmlist = LIST_HEAD_INIT(efi_mm.mmlist), | |
| 40 | }; | |
| 41 | ||
| 42 | static bool __init efi_virtmap_init(void) | |
| 43 | { | |
| 44 | efi_memory_desc_t *md; | |
| 45 | ||
| f7d92489 | 46 | efi_mm.pgd = pgd_alloc(&efi_mm); |
| e5bc22a4 AB |
47 | init_new_context(NULL, &efi_mm); |
| 48 | ||
| 49 | for_each_efi_memory_desc(&memmap, md) { | |
| f7d92489 AB |
50 | phys_addr_t phys = md->phys_addr; |
| 51 | int ret; | |
| e5bc22a4 AB |
52 | |
| 53 | if (!(md->attribute & EFI_MEMORY_RUNTIME)) | |
| 54 | continue; | |
| 55 | if (md->virt_addr == 0) | |
| 56 | return false; | |
| 57 | ||
| f7d92489 AB |
58 | ret = efi_create_mapping(&efi_mm, md); |
| 59 | if (!ret) { | |
| 60 | pr_info(" EFI remap %pa => %p\n", | |
| 61 | &phys, (void *)(unsigned long)md->virt_addr); | |
| 62 | } else { | |
| 63 | pr_warn(" EFI remap %pa: failed to create mapping (%d)\n", | |
| 64 | &phys, ret); | |
| 65 | return false; | |
| 66 | } | |
| e5bc22a4 AB |
67 | } |
| 68 | return true; | |
| 69 | } | |
| 70 | ||
| 71 | /* | |
| 72 | * Enable the UEFI Runtime Services if all prerequisites are in place, i.e., | |
| 73 | * non-early mapping of the UEFI system table and virtual mappings for all | |
| 74 | * EFI_MEMORY_RUNTIME regions. | |
| 75 | */ | |
| f7d92489 | 76 | static int __init arm_enable_runtime_services(void) |
| e5bc22a4 AB |
77 | { |
| 78 | u64 mapsize; | |
| 79 | ||
| 80 | if (!efi_enabled(EFI_BOOT)) { | |
| 81 | pr_info("EFI services will not be available.\n"); | |
| 82 | return 0; | |
| 83 | } | |
| 84 | ||
| 85 | if (efi_runtime_disabled()) { | |
| 86 | pr_info("EFI runtime services will be disabled.\n"); | |
| 87 | return 0; | |
| 88 | } | |
| 89 | ||
| 90 | pr_info("Remapping and enabling EFI services.\n"); | |
| 91 | ||
| 92 | mapsize = memmap.map_end - memmap.map; | |
| 93 | memmap.map = (__force void *)ioremap_cache(memmap.phys_map, | |
| 94 | mapsize); | |
| 95 | if (!memmap.map) { | |
| 96 | pr_err("Failed to remap EFI memory map\n"); | |
| 97 | return -ENOMEM; | |
| 98 | } | |
| 99 | memmap.map_end = memmap.map + mapsize; | |
| 100 | efi.memmap = &memmap; | |
| 101 | ||
| 102 | efi.systab = (__force void *)ioremap_cache(efi_system_table, | |
| 103 | sizeof(efi_system_table_t)); | |
| 104 | if (!efi.systab) { | |
| 105 | pr_err("Failed to remap EFI System Table\n"); | |
| 106 | return -ENOMEM; | |
| 107 | } | |
| 108 | set_bit(EFI_SYSTEM_TABLES, &efi.flags); | |
| 109 | ||
| 110 | if (!efi_virtmap_init()) { | |
| 111 | pr_err("No UEFI virtual mapping was installed -- runtime services will not be available\n"); | |
| 112 | return -ENOMEM; | |
| 113 | } | |
| 114 | ||
| 115 | /* Set up runtime services function pointers */ | |
| 116 | efi_native_runtime_setup(); | |
| 117 | set_bit(EFI_RUNTIME_SERVICES, &efi.flags); | |
| 118 | ||
| 119 | efi.runtime_version = efi.systab->hdr.revision; | |
| 120 | ||
| 121 | return 0; | |
| 122 | } | |
| f7d92489 | 123 | early_initcall(arm_enable_runtime_services); |
| e5bc22a4 AB |
124 | |
| 125 | void efi_virtmap_load(void) | |
| 126 | { | |
| 127 | preempt_disable(); | |
| 128 | efi_set_pgd(&efi_mm); | |
| 129 | } | |
| 130 | ||
| 131 | void efi_virtmap_unload(void) | |
| 132 | { | |
| 133 | efi_set_pgd(current->active_mm); | |
| 134 | preempt_enable(); | |
| 135 | } |