/* * Extensible Firmware Interface * * Based on Extensible Firmware Interface Specification version 2.4 * * Copyright (C) 2013, 2014 Linaro Ltd. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. * */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include struct efi_memory_map memmap; static u64 efi_system_table; static pgd_t efi_pgd[PTRS_PER_PGD] __page_aligned_bss; static struct mm_struct efi_mm = { .mm_rb = RB_ROOT, .pgd = efi_pgd, .mm_users = ATOMIC_INIT(2), .mm_count = ATOMIC_INIT(1), .mmap_sem = __RWSEM_INITIALIZER(efi_mm.mmap_sem), .page_table_lock = __SPIN_LOCK_UNLOCKED(efi_mm.page_table_lock), .mmlist = LIST_HEAD_INIT(efi_mm.mmlist), INIT_MM_CONTEXT(efi_mm) }; static int __init is_normal_ram(efi_memory_desc_t *md) { if (md->attribute & EFI_MEMORY_WB) return 1; return 0; } /* * Translate a EFI virtual address into a physical address: this is necessary, * as some data members of the EFI system table are virtually remapped after * SetVirtualAddressMap() has been called. */ static phys_addr_t efi_to_phys(unsigned long addr) { efi_memory_desc_t *md; for_each_efi_memory_desc(&memmap, md) { if (!(md->attribute & EFI_MEMORY_RUNTIME)) continue; if (md->virt_addr == 0) /* no virtual mapping has been installed by the stub */ break; if (md->virt_addr <= addr && (addr - md->virt_addr) < (md->num_pages << EFI_PAGE_SHIFT)) return md->phys_addr + addr - md->virt_addr; } return addr; } static int __init uefi_init(void) { efi_char16_t *c16; void *config_tables; u64 table_size; char vendor[100] = "unknown"; int i, retval; efi.systab = early_memremap(efi_system_table, sizeof(efi_system_table_t)); if (efi.systab == NULL) { pr_warn("Unable to map EFI system table.\n"); return -ENOMEM; } set_bit(EFI_BOOT, &efi.flags); set_bit(EFI_64BIT, &efi.flags); /* * Verify the EFI Table */ if (efi.systab->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE) { pr_err("System table signature incorrect\n"); retval = -EINVAL; goto out; } if ((efi.systab->hdr.revision >> 16) < 2) pr_warn("Warning: EFI system table version %d.%02d, expected 2.00 or greater\n", efi.systab->hdr.revision >> 16, efi.systab->hdr.revision & 0xffff); /* Show what we know for posterity */ c16 = early_memremap(efi_to_phys(efi.systab->fw_vendor), sizeof(vendor) * sizeof(efi_char16_t)); if (c16) { for (i = 0; i < (int) sizeof(vendor) - 1 && *c16; ++i) vendor[i] = c16[i]; vendor[i] = '\0'; early_memunmap(c16, sizeof(vendor) * sizeof(efi_char16_t)); } pr_info("EFI v%u.%.02u by %s\n", efi.systab->hdr.revision >> 16, efi.systab->hdr.revision & 0xffff, vendor); table_size = sizeof(efi_config_table_64_t) * efi.systab->nr_tables; config_tables = early_memremap(efi_to_phys(efi.systab->tables), table_size); retval = efi_config_parse_tables(config_tables, efi.systab->nr_tables, sizeof(efi_config_table_64_t), NULL); early_memunmap(config_tables, table_size); out: early_memunmap(efi.systab, sizeof(efi_system_table_t)); return retval; } /* * Return true for RAM regions we want to permanently reserve. */ static __init int is_reserve_region(efi_memory_desc_t *md) { switch (md->type) { case EFI_LOADER_CODE: case EFI_LOADER_DATA: case EFI_BOOT_SERVICES_CODE: case EFI_BOOT_SERVICES_DATA: case EFI_CONVENTIONAL_MEMORY: case EFI_PERSISTENT_MEMORY: return 0; default: break; } return is_normal_ram(md); } static __init void reserve_regions(void) { efi_memory_desc_t *md; u64 paddr, npages, size; if (efi_enabled(EFI_DBG)) pr_info("Processing EFI memory map:\n"); for_each_efi_memory_desc(&memmap, md) { paddr = md->phys_addr; npages = md->num_pages; if (efi_enabled(EFI_DBG)) { char buf[64]; pr_info(" 0x%012llx-0x%012llx %s", paddr, paddr + (npages << EFI_PAGE_SHIFT) - 1, efi_md_typeattr_format(buf, sizeof(buf), md)); } memrange_efi_to_native(&paddr, &npages); size = npages << PAGE_SHIFT; if (is_normal_ram(md)) early_init_dt_add_memory_arch(paddr, size); if (is_reserve_region(md)) { memblock_reserve(paddr, size); if (efi_enabled(EFI_DBG)) pr_cont("*"); } if (efi_enabled(EFI_DBG)) pr_cont("\n"); } set_bit(EFI_MEMMAP, &efi.flags); } void __init efi_init(void) { struct efi_fdt_params params; /* Grab UEFI information placed in FDT by stub */ if (!efi_get_fdt_params(¶ms)) return; efi_system_table = params.system_table; memblock_reserve(params.mmap & PAGE_MASK, PAGE_ALIGN(params.mmap_size + (params.mmap & ~PAGE_MASK))); memmap.phys_map = params.mmap; memmap.map = early_memremap(params.mmap, params.mmap_size); memmap.map_end = memmap.map + params.mmap_size; memmap.desc_size = params.desc_size; memmap.desc_version = params.desc_ver; if (uefi_init() < 0) return; reserve_regions(); early_memunmap(memmap.map, params.mmap_size); } static bool __init efi_virtmap_init(void) { efi_memory_desc_t *md; for_each_efi_memory_desc(&memmap, md) { u64 paddr, npages, size; pgprot_t prot; if (!(md->attribute & EFI_MEMORY_RUNTIME)) continue; if (md->virt_addr == 0) return false; paddr = md->phys_addr; npages = md->num_pages; memrange_efi_to_native(&paddr, &npages); size = npages << PAGE_SHIFT; pr_info(" EFI remap 0x%016llx => %p\n", md->phys_addr, (void *)md->virt_addr); /* * Only regions of type EFI_RUNTIME_SERVICES_CODE need to be * executable, everything else can be mapped with the XN bits * set. */ if (!is_normal_ram(md)) prot = __pgprot(PROT_DEVICE_nGnRE); else if (md->type == EFI_RUNTIME_SERVICES_CODE || !PAGE_ALIGNED(md->phys_addr)) prot = PAGE_KERNEL_EXEC; else prot = PAGE_KERNEL; create_pgd_mapping(&efi_mm, paddr, md->virt_addr, size, prot); } return true; } /* * Enable the UEFI Runtime Services if all prerequisites are in place, i.e., * non-early mapping of the UEFI system table and virtual mappings for all * EFI_MEMORY_RUNTIME regions. */ static int __init arm64_enable_runtime_services(void) { u64 mapsize; if (!efi_enabled(EFI_BOOT)) { pr_info("EFI services will not be available.\n"); return -1; } if (efi_runtime_disabled()) { pr_info("EFI runtime services will be disabled.\n"); return -1; } pr_info("Remapping and enabling EFI services.\n"); mapsize = memmap.map_end - memmap.map; memmap.map = (__force void *)ioremap_cache(memmap.phys_map, mapsize); if (!memmap.map) { pr_err("Failed to remap EFI memory map\n"); return -1; } memmap.map_end = memmap.map + mapsize; efi.memmap = &memmap; efi.systab = (__force void *)ioremap_cache(efi_system_table, sizeof(efi_system_table_t)); if (!efi.systab) { pr_err("Failed to remap EFI System Table\n"); return -1; } set_bit(EFI_SYSTEM_TABLES, &efi.flags); if (!efi_virtmap_init()) { pr_err("No UEFI virtual mapping was installed -- runtime services will not be available\n"); return -1; } /* Set up runtime services function pointers */ efi_native_runtime_setup(); set_bit(EFI_RUNTIME_SERVICES, &efi.flags); efi.runtime_version = efi.systab->hdr.revision; return 0; } early_initcall(arm64_enable_runtime_services); static int __init arm64_dmi_init(void) { /* * On arm64, DMI depends on UEFI, and dmi_scan_machine() needs to * be called early because dmi_id_init(), which is an arch_initcall * itself, depends on dmi_scan_machine() having been called already. */ dmi_scan_machine(); if (dmi_available) dmi_set_dump_stack_arch_desc(); return 0; } core_initcall(arm64_dmi_init); static void efi_set_pgd(struct mm_struct *mm) { if (mm == &init_mm) cpu_set_reserved_ttbr0(); else cpu_switch_mm(mm->pgd, mm); flush_tlb_all(); if (icache_is_aivivt()) __flush_icache_all(); } void efi_virtmap_load(void) { preempt_disable(); efi_set_pgd(&efi_mm); } void efi_virtmap_unload(void) { efi_set_pgd(current->active_mm); preempt_enable(); } /* * UpdateCapsule() depends on the system being shutdown via * ResetSystem(). */ bool efi_poweroff_required(void) { return efi_enabled(EFI_RUNTIME_SERVICES); }