| /* |
| * Extensible Firmware Interface |
| * |
| * Based on Extensible Firmware Interface Specification version 2.4 |
| * |
| * Copyright (C) 2013 - 2015 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. |
| * |
| */ |
| |
| #define pr_fmt(fmt) "efi: " fmt |
| |
| #include <linux/efi.h> |
| #include <linux/init.h> |
| #include <linux/memblock.h> |
| #include <linux/mm_types.h> |
| #include <linux/of.h> |
| #include <linux/of_fdt.h> |
| #include <linux/platform_device.h> |
| #include <linux/screen_info.h> |
| |
| #include <asm/efi.h> |
| |
| u64 efi_system_table; |
| |
| static int __init is_memory(efi_memory_desc_t *md) |
| { |
| if (md->attribute & (EFI_MEMORY_WB|EFI_MEMORY_WT|EFI_MEMORY_WC)) |
| 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(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 __initdata unsigned long screen_info_table = EFI_INVALID_TABLE_ADDR; |
| |
| static __initdata efi_config_table_type_t arch_tables[] = { |
| {LINUX_EFI_ARM_SCREEN_INFO_TABLE_GUID, NULL, &screen_info_table}, |
| {NULL_GUID, NULL, NULL} |
| }; |
| |
| static void __init init_screen_info(void) |
| { |
| struct screen_info *si; |
| |
| if (screen_info_table != EFI_INVALID_TABLE_ADDR) { |
| si = early_memremap_ro(screen_info_table, sizeof(*si)); |
| if (!si) { |
| pr_err("Could not map screen_info config table\n"); |
| return; |
| } |
| screen_info = *si; |
| early_memunmap(si, sizeof(*si)); |
| |
| /* dummycon on ARM needs non-zero values for columns/lines */ |
| screen_info.orig_video_cols = 80; |
| screen_info.orig_video_lines = 25; |
| } |
| |
| if (screen_info.orig_video_isVGA == VIDEO_TYPE_EFI && |
| memblock_is_map_memory(screen_info.lfb_base)) |
| memblock_mark_nomap(screen_info.lfb_base, screen_info.lfb_size); |
| } |
| |
| static int __init uefi_init(void) |
| { |
| efi_char16_t *c16; |
| void *config_tables; |
| size_t table_size; |
| char vendor[100] = "unknown"; |
| int i, retval; |
| |
| efi.systab = early_memremap_ro(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); |
| if (IS_ENABLED(CONFIG_64BIT)) |
| 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); |
| |
| efi.runtime_version = efi.systab->hdr.revision; |
| |
| /* Show what we know for posterity */ |
| c16 = early_memremap_ro(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_ro(efi_to_phys(efi.systab->tables), |
| table_size); |
| if (config_tables == NULL) { |
| pr_warn("Unable to map EFI config table array.\n"); |
| retval = -ENOMEM; |
| goto out; |
| } |
| retval = efi_config_parse_tables(config_tables, efi.systab->nr_tables, |
| sizeof(efi_config_table_t), |
| arch_tables); |
| |
| early_memunmap(config_tables, table_size); |
| out: |
| early_memunmap(efi.systab, sizeof(efi_system_table_t)); |
| return retval; |
| } |
| |
| /* |
| * Return true for regions that can be used as System RAM. |
| */ |
| static __init int is_usable_memory(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: |
| /* |
| * According to the spec, these regions are no longer reserved |
| * after calling ExitBootServices(). However, we can only use |
| * them as System RAM if they can be mapped writeback cacheable. |
| */ |
| return (md->attribute & EFI_MEMORY_WB); |
| default: |
| break; |
| } |
| return false; |
| } |
| |
| 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"); |
| |
| /* |
| * Discard memblocks discovered so far: if there are any at this |
| * point, they originate from memory nodes in the DT, and UEFI |
| * uses its own memory map instead. |
| */ |
| memblock_dump_all(); |
| memblock_remove(0, (phys_addr_t)ULLONG_MAX); |
| |
| for_each_efi_memory_desc(md) { |
| paddr = md->phys_addr; |
| npages = md->num_pages; |
| |
| if (efi_enabled(EFI_DBG)) { |
| char buf[64]; |
| |
| pr_info(" 0x%012llx-0x%012llx %s\n", |
| 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_memory(md)) { |
| early_init_dt_add_memory_arch(paddr, size); |
| |
| if (!is_usable_memory(md)) |
| memblock_mark_nomap(paddr, size); |
| } |
| } |
| } |
| |
| void __init efi_init(void) |
| { |
| struct efi_memory_map_data data; |
| 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; |
| |
| data.desc_version = params.desc_ver; |
| data.desc_size = params.desc_size; |
| data.size = params.mmap_size; |
| data.phys_map = params.mmap; |
| |
| if (efi_memmap_init_early(&data) < 0) { |
| /* |
| * If we are booting via UEFI, the UEFI memory map is the only |
| * description of memory we have, so there is little point in |
| * proceeding if we cannot access it. |
| */ |
| panic("Unable to map EFI memory map.\n"); |
| } |
| |
| WARN(efi.memmap.desc_version != 1, |
| "Unexpected EFI_MEMORY_DESCRIPTOR version %ld", |
| efi.memmap.desc_version); |
| |
| if (uefi_init() < 0) { |
| efi_memmap_unmap(); |
| return; |
| } |
| |
| reserve_regions(); |
| efi_memattr_init(); |
| efi_esrt_init(); |
| efi_memmap_unmap(); |
| |
| memblock_reserve(params.mmap & PAGE_MASK, |
| PAGE_ALIGN(params.mmap_size + |
| (params.mmap & ~PAGE_MASK))); |
| |
| init_screen_info(); |
| } |
| |
| static int __init register_gop_device(void) |
| { |
| void *pd; |
| |
| if (screen_info.orig_video_isVGA != VIDEO_TYPE_EFI) |
| return 0; |
| |
| pd = platform_device_register_data(NULL, "efi-framebuffer", 0, |
| &screen_info, sizeof(screen_info)); |
| return PTR_ERR_OR_ZERO(pd); |
| } |
| subsys_initcall(register_gop_device); |