From 16c220d0a79feed0326c29d64e4bb482e80276d4 Mon Sep 17 00:00:00 2001 From: Simon Glass Date: Tue, 4 Aug 2015 12:33:58 -0600 Subject: [PATCH] efi: Add functions for decoding the EFI tables The EFI stub can pass a table to U-Boot with information about the memory map Potentially other things will follow. Add a way to access this table. Signed-off-by: Simon Glass Reviewed-by: Bin Meng --- lib/efi/Makefile | 1 + lib/efi/efi_info.c | 47 ++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 48 insertions(+) create mode 100644 lib/efi/efi_info.c diff --git a/lib/efi/Makefile b/lib/efi/Makefile index 4bc67f01f9..e32dc14f3d 100644 --- a/lib/efi/Makefile +++ b/lib/efi/Makefile @@ -5,6 +5,7 @@ # obj-$(CONFIG_EFI_APP) += efi_app.o efi.o +obj-$(CONFIG_EFI_STUB) += efi_info.o CFLAGS_REMOVE_efi_stub.o := -mregparm=3 \ $(if $(CONFIG_EFI_STUB_64BIT),-march=i386 -m32) diff --git a/lib/efi/efi_info.c b/lib/efi/efi_info.c new file mode 100644 index 0000000000..0cd9a7e9c7 --- /dev/null +++ b/lib/efi/efi_info.c @@ -0,0 +1,47 @@ +/* + * Copyright (c) 2015 Google, Inc + * + * SPDX-License-Identifier: GPL-2.0+ + * + * Access to the EFI information table + */ + +#include +#include +#include +#include + +int efi_info_get(enum efi_entry_t type, void **datap, int *sizep) +{ + struct efi_entry_hdr *entry; + struct efi_info_hdr *info; + int ret; + + if (!gd->arch.table) + return -ENODATA; + + info = map_sysmem(gd->arch.table, 0); + if (info->version != EFI_TABLE_VERSION) { + ret = -EPROTONOSUPPORT; + goto err; + } + + entry = (struct efi_entry_hdr *)((ulong)info + info->hdr_size); + while (entry->type != EFIET_END) { + if (entry->type == type) { + if (entry->addr) + *datap = map_sysmem(entry->addr, entry->size); + else + *datap = entry + 1; + *sizep = entry->size; + return 0; + } + entry = (struct efi_entry_hdr *)((ulong)entry + entry->link); + } + + ret = -ENOENT; +err: + unmap_sysmem(info); + + return ret; +} -- 2.25.1