Merge branch 'x86-efi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 EFI changes from Ingo Molnar:
 "Main changes:

   - Add support for earlyprintk=efi which uses the EFI framebuffer.
     Very useful for debugging boot problems.

   - EFI stub support for large memory maps (more than 128 entries)

   - EFI ARM support - this was mostly done by generalizing x86 <-> ARM
     platform differences, such as by moving x86 EFI code into
     drivers/firmware/efi/ and sharing it with ARM.

   - Documentation updates

   - misc fixes"

* 'x86-efi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (26 commits)
  x86/efi: Add EFI framebuffer earlyprintk support
  boot, efi: Remove redundant memset()
  x86/efi: Fix config_table_type array termination
  x86 efi: bugfix interrupt disabling sequence
  x86: EFI stub support for large memory maps
  efi: resolve warnings found on ARM compile
  efi: Fix types in EFI calls to match EFI function definitions.
  efi: Renames in handle_cmdline_files() to complete generalization.
  efi: Generalize handle_ramdisks() and rename to handle_cmdline_files().
  efi: Allow efi_free() to be called with size of 0
  efi: use efi_get_memory_map() to get final map for x86
  efi: generalize efi_get_memory_map()
  efi: Rename __get_map() to efi_get_memory_map()
  efi: Move unicode to ASCII conversion to shared function.
  efi: Generalize relocate_kernel() for use by other architectures.
  efi: Move relocate_kernel() to shared file.
  efi: Enforce minimum alignment of 1 page on allocations.
  efi: Rename memory allocation/free functions
  efi: Add system table pointer argument to shared functions.
  efi: Move common EFI stub code from x86 arch code to common location
  ...

3 files changed, 777 insertions, 1 deletions

diff --git a/drivers/firmware/efi/efi-stub-helper.c b/drivers/firmware/efi/efi-stub-helper.c
new file mode 100644
index 00000000000..b6bffbfd3be
--- /dev/null
+++ b/drivers/firmware/efi/efi-stub-helper.c
@@ -0,0 +1,636 @@
+/*
+ * Helper functions used by the EFI stub on multiple
+ * architectures. This should be #included by the EFI stub
+ * implementation files.
+ *
+ * Copyright 2011 Intel Corporation; author Matt Fleming
+ *
+ * This file is part of the Linux kernel, and is made available
+ * under the terms of the GNU General Public License version 2.
+ *
+ */
+#define EFI_READ_CHUNK_SIZE	(1024 * 1024)
+
+struct file_info {
+	efi_file_handle_t *handle;
+	u64 size;
+};
+
+
+
+
+static void efi_char16_printk(efi_system_table_t *sys_table_arg,
+			      efi_char16_t *str)
+{
+	struct efi_simple_text_output_protocol *out;
+
+	out = (struct efi_simple_text_output_protocol *)sys_table_arg->con_out;
+	efi_call_phys2(out->output_string, out, str);
+}
+
+static void efi_printk(efi_system_table_t *sys_table_arg, char *str)
+{
+	char *s8;
+
+	for (s8 = str; *s8; s8++) {
+		efi_char16_t ch[2] = { 0 };
+
+		ch[0] = *s8;
+		if (*s8 == '\n') {
+			efi_char16_t nl[2] = { '\r', 0 };
+			efi_char16_printk(sys_table_arg, nl);
+		}
+
+		efi_char16_printk(sys_table_arg, ch);
+	}
+}
+
+
+static efi_status_t efi_get_memory_map(efi_system_table_t *sys_table_arg,
+				       efi_memory_desc_t **map,
+				       unsigned long *map_size,
+				       unsigned long *desc_size,
+				       u32 *desc_ver,
+				       unsigned long *key_ptr)
+{
+	efi_memory_desc_t *m = NULL;
+	efi_status_t status;
+	unsigned long key;
+	u32 desc_version;
+
+	*map_size = sizeof(*m) * 32;
+again:
+	/*
+	 * Add an additional efi_memory_desc_t because we're doing an
+	 * allocation which may be in a new descriptor region.
+	 */
+	*map_size += sizeof(*m);
+	status = efi_call_phys3(sys_table_arg->boottime->allocate_pool,
+				EFI_LOADER_DATA, *map_size, (void **)&m);
+	if (status != EFI_SUCCESS)
+		goto fail;
+
+	status = efi_call_phys5(sys_table_arg->boottime->get_memory_map,
+				map_size, m, &key, desc_size, &desc_version);
+	if (status == EFI_BUFFER_TOO_SMALL) {
+		efi_call_phys1(sys_table_arg->boottime->free_pool, m);
+		goto again;
+	}
+
+	if (status != EFI_SUCCESS)
+		efi_call_phys1(sys_table_arg->boottime->free_pool, m);
+	if (key_ptr && status == EFI_SUCCESS)
+		*key_ptr = key;
+	if (desc_ver && status == EFI_SUCCESS)
+		*desc_ver = desc_version;
+
+fail:
+	*map = m;
+	return status;
+}
+
+/*
+ * Allocate at the highest possible address that is not above 'max'.
+ */
+static efi_status_t efi_high_alloc(efi_system_table_t *sys_table_arg,
+			       unsigned long size, unsigned long align,
+			       unsigned long *addr, unsigned long max)
+{
+	unsigned long map_size, desc_size;
+	efi_memory_desc_t *map;
+	efi_status_t status;
+	unsigned long nr_pages;
+	u64 max_addr = 0;
+	int i;
+
+	status = efi_get_memory_map(sys_table_arg, &map, &map_size, &desc_size,
+				    NULL, NULL);
+	if (status != EFI_SUCCESS)
+		goto fail;
+
+	/*
+	 * Enforce minimum alignment that EFI requires when requesting
+	 * a specific address.  We are doing page-based allocations,
+	 * so we must be aligned to a page.
+	 */
+	if (align < EFI_PAGE_SIZE)
+		align = EFI_PAGE_SIZE;
+
+	nr_pages = round_up(size, EFI_PAGE_SIZE) / EFI_PAGE_SIZE;
+again:
+	for (i = 0; i < map_size / desc_size; i++) {
+		efi_memory_desc_t *desc;
+		unsigned long m = (unsigned long)map;
+		u64 start, end;
+
+		desc = (efi_memory_desc_t *)(m + (i * desc_size));
+		if (desc->type != EFI_CONVENTIONAL_MEMORY)
+			continue;
+
+		if (desc->num_pages < nr_pages)
+			continue;
+
+		start = desc->phys_addr;
+		end = start + desc->num_pages * (1UL << EFI_PAGE_SHIFT);
+
+		if ((start + size) > end || (start + size) > max)
+			continue;
+
+		if (end - size > max)
+			end = max;
+
+		if (round_down(end - size, align) < start)
+			continue;
+
+		start = round_down(end - size, align);
+
+		/*
+		 * Don't allocate at 0x0. It will confuse code that
+		 * checks pointers against NULL.
+		 */
+		if (start == 0x0)
+			continue;
+
+		if (start > max_addr)
+			max_addr = start;
+	}
+
+	if (!max_addr)
+		status = EFI_NOT_FOUND;
+	else {
+		status = efi_call_phys4(sys_table_arg->boottime->allocate_pages,
+					EFI_ALLOCATE_ADDRESS, EFI_LOADER_DATA,
+					nr_pages, &max_addr);
+		if (status != EFI_SUCCESS) {
+			max = max_addr;
+			max_addr = 0;
+			goto again;
+		}
+
+		*addr = max_addr;
+	}
+
+	efi_call_phys1(sys_table_arg->boottime->free_pool, map);
+
+fail:
+	return status;
+}
+
+/*
+ * Allocate at the lowest possible address.
+ */
+static efi_status_t efi_low_alloc(efi_system_table_t *sys_table_arg,
+			      unsigned long size, unsigned long align,
+			      unsigned long *addr)
+{
+	unsigned long map_size, desc_size;
+	efi_memory_desc_t *map;
+	efi_status_t status;
+	unsigned long nr_pages;
+	int i;
+
+	status = efi_get_memory_map(sys_table_arg, &map, &map_size, &desc_size,
+				    NULL, NULL);
+	if (status != EFI_SUCCESS)
+		goto fail;
+
+	/*
+	 * Enforce minimum alignment that EFI requires when requesting
+	 * a specific address.  We are doing page-based allocations,
+	 * so we must be aligned to a page.
+	 */
+	if (align < EFI_PAGE_SIZE)
+		align = EFI_PAGE_SIZE;
+
+	nr_pages = round_up(size, EFI_PAGE_SIZE) / EFI_PAGE_SIZE;
+	for (i = 0; i < map_size / desc_size; i++) {
+		efi_memory_desc_t *desc;
+		unsigned long m = (unsigned long)map;
+		u64 start, end;
+
+		desc = (efi_memory_desc_t *)(m + (i * desc_size));
+
+		if (desc->type != EFI_CONVENTIONAL_MEMORY)
+			continue;
+
+		if (desc->num_pages < nr_pages)
+			continue;
+
+		start = desc->phys_addr;
+		end = start + desc->num_pages * (1UL << EFI_PAGE_SHIFT);
+
+		/*
+		 * Don't allocate at 0x0. It will confuse code that
+		 * checks pointers against NULL. Skip the first 8
+		 * bytes so we start at a nice even number.
+		 */
+		if (start == 0x0)
+			start += 8;
+
+		start = round_up(start, align);
+		if ((start + size) > end)
+			continue;
+
+		status = efi_call_phys4(sys_table_arg->boottime->allocate_pages,
+					EFI_ALLOCATE_ADDRESS, EFI_LOADER_DATA,
+					nr_pages, &start);
+		if (status == EFI_SUCCESS) {
+			*addr = start;
+			break;
+		}
+	}
+
+	if (i == map_size / desc_size)
+		status = EFI_NOT_FOUND;
+
+	efi_call_phys1(sys_table_arg->boottime->free_pool, map);
+fail:
+	return status;
+}
+
+static void efi_free(efi_system_table_t *sys_table_arg, unsigned long size,
+		     unsigned long addr)
+{
+	unsigned long nr_pages;
+
+	if (!size)
+		return;
+
+	nr_pages = round_up(size, EFI_PAGE_SIZE) / EFI_PAGE_SIZE;
+	efi_call_phys2(sys_table_arg->boottime->free_pages, addr, nr_pages);
+}
+
+
+/*
+ * Check the cmdline for a LILO-style file= arguments.
+ *
+ * We only support loading a file from the same filesystem as
+ * the kernel image.
+ */
+static efi_status_t handle_cmdline_files(efi_system_table_t *sys_table_arg,
+					 efi_loaded_image_t *image,
+					 char *cmd_line, char *option_string,
+					 unsigned long max_addr,
+					 unsigned long *load_addr,
+					 unsigned long *load_size)
+{
+	struct file_info *files;
+	unsigned long file_addr;
+	efi_guid_t fs_proto = EFI_FILE_SYSTEM_GUID;
+	u64 file_size_total;
+	efi_file_io_interface_t *io;
+	efi_file_handle_t *fh;
+	efi_status_t status;
+	int nr_files;
+	char *str;
+	int i, j, k;
+
+	file_addr = 0;
+	file_size_total = 0;
+
+	str = cmd_line;
+
+	j = 0;			/* See close_handles */
+
+	if (!load_addr || !load_size)
+		return EFI_INVALID_PARAMETER;
+
+	*load_addr = 0;
+	*load_size = 0;
+
+	if (!str || !*str)
+		return EFI_SUCCESS;
+
+	for (nr_files = 0; *str; nr_files++) {
+		str = strstr(str, option_string);
+		if (!str)
+			break;
+
+		str += strlen(option_string);
+
+		/* Skip any leading slashes */
+		while (*str == '/' || *str == '\\')
+			str++;
+
+		while (*str && *str != ' ' && *str != '\n')
+			str++;
+	}
+
+	if (!nr_files)
+		return EFI_SUCCESS;
+
+	status = efi_call_phys3(sys_table_arg->boottime->allocate_pool,
+				EFI_LOADER_DATA,
+				nr_files * sizeof(*files),
+				(void **)&files);
+	if (status != EFI_SUCCESS) {
+		efi_printk(sys_table_arg, "Failed to alloc mem for file handle list\n");
+		goto fail;
+	}
+
+	str = cmd_line;
+	for (i = 0; i < nr_files; i++) {
+		struct file_info *file;
+		efi_file_handle_t *h;
+		efi_file_info_t *info;
+		efi_char16_t filename_16[256];
+		unsigned long info_sz;
+		efi_guid_t info_guid = EFI_FILE_INFO_ID;
+		efi_char16_t *p;
+		u64 file_sz;
+
+		str = strstr(str, option_string);
+		if (!str)
+			break;
+
+		str += strlen(option_string);
+
+		file = &files[i];
+		p = filename_16;
+
+		/* Skip any leading slashes */
+		while (*str == '/' || *str == '\\')
+			str++;
+
+		while (*str && *str != ' ' && *str != '\n') {
+			if ((u8 *)p >= (u8 *)filename_16 + sizeof(filename_16))
+				break;
+
+			if (*str == '/') {
+				*p++ = '\\';
+				str++;
+			} else {
+				*p++ = *str++;
+			}
+		}
+
+		*p = '\0';
+
+		/* Only open the volume once. */
+		if (!i) {
+			efi_boot_services_t *boottime;
+
+			boottime = sys_table_arg->boottime;
+
+			status = efi_call_phys3(boottime->handle_protocol,
+					image->device_handle, &fs_proto,
+						(void **)&io);
+			if (status != EFI_SUCCESS) {
+				efi_printk(sys_table_arg, "Failed to handle fs_proto\n");
+				goto free_files;
+			}
+
+			status = efi_call_phys2(io->open_volume, io, &fh);
+			if (status != EFI_SUCCESS) {
+				efi_printk(sys_table_arg, "Failed to open volume\n");
+				goto free_files;
+			}
+		}
+
+		status = efi_call_phys5(fh->open, fh, &h, filename_16,
+					EFI_FILE_MODE_READ, (u64)0);
+		if (status != EFI_SUCCESS) {
+			efi_printk(sys_table_arg, "Failed to open file: ");
+			efi_char16_printk(sys_table_arg, filename_16);
+			efi_printk(sys_table_arg, "\n");
+			goto close_handles;
+		}
+
+		file->handle = h;
+
+		info_sz = 0;
+		status = efi_call_phys4(h->get_info, h, &info_guid,
+					&info_sz, NULL);
+		if (status != EFI_BUFFER_TOO_SMALL) {
+			efi_printk(sys_table_arg, "Failed to get file info size\n");
+			goto close_handles;
+		}
+
+grow:
+		status = efi_call_phys3(sys_table_arg->boottime->allocate_pool,
+					EFI_LOADER_DATA, info_sz,
+					(void **)&info);
+		if (status != EFI_SUCCESS) {
+			efi_printk(sys_table_arg, "Failed to alloc mem for file info\n");
+			goto close_handles;
+		}
+
+		status = efi_call_phys4(h->get_info, h, &info_guid,
+					&info_sz, info);
+		if (status == EFI_BUFFER_TOO_SMALL) {
+			efi_call_phys1(sys_table_arg->boottime->free_pool,
+				       info);
+			goto grow;
+		}
+
+		file_sz = info->file_size;
+		efi_call_phys1(sys_table_arg->boottime->free_pool, info);
+
+		if (status != EFI_SUCCESS) {
+			efi_printk(sys_table_arg, "Failed to get file info\n");
+			goto close_handles;
+		}
+
+		file->size = file_sz;
+		file_size_total += file_sz;
+	}
+
+	if (file_size_total) {
+		unsigned long addr;
+
+		/*
+		 * Multiple files need to be at consecutive addresses in memory,
+		 * so allocate enough memory for all the files.  This is used
+		 * for loading multiple files.
+		 */
+		status = efi_high_alloc(sys_table_arg, file_size_total, 0x1000,
+				    &file_addr, max_addr);
+		if (status != EFI_SUCCESS) {
+			efi_printk(sys_table_arg, "Failed to alloc highmem for files\n");
+			goto close_handles;
+		}
+
+		/* We've run out of free low memory. */
+		if (file_addr > max_addr) {
+			efi_printk(sys_table_arg, "We've run out of free low memory\n");
+			status = EFI_INVALID_PARAMETER;
+			goto free_file_total;
+		}
+
+		addr = file_addr;
+		for (j = 0; j < nr_files; j++) {
+			unsigned long size;
+
+			size = files[j].size;
+			while (size) {
+				unsigned long chunksize;
+				if (size > EFI_READ_CHUNK_SIZE)
+					chunksize = EFI_READ_CHUNK_SIZE;
+				else
+					chunksize = size;
+				status = efi_call_phys3(fh->read,
+							files[j].handle,
+							&chunksize,
+							(void *)addr);
+				if (status != EFI_SUCCESS) {
+					efi_printk(sys_table_arg, "Failed to read file\n");
+					goto free_file_total;
+				}
+				addr += chunksize;
+				size -= chunksize;
+			}
+
+			efi_call_phys1(fh->close, files[j].handle);
+		}
+
+	}
+
+	efi_call_phys1(sys_table_arg->boottime->free_pool, files);
+
+	*load_addr = file_addr;
+	*load_size = file_size_total;
+
+	return status;
+
+free_file_total:
+	efi_free(sys_table_arg, file_size_total, file_addr);
+
+close_handles:
+	for (k = j; k < i; k++)
+		efi_call_phys1(fh->close, files[k].handle);
+free_files:
+	efi_call_phys1(sys_table_arg->boottime->free_pool, files);
+fail:
+	*load_addr = 0;
+	*load_size = 0;
+
+	return status;
+}
+/*
+ * Relocate a kernel image, either compressed or uncompressed.
+ * In the ARM64 case, all kernel images are currently
+ * uncompressed, and as such when we relocate it we need to
+ * allocate additional space for the BSS segment. Any low
+ * memory that this function should avoid needs to be
+ * unavailable in the EFI memory map, as if the preferred
+ * address is not available the lowest available address will
+ * be used.
+ */
+static efi_status_t efi_relocate_kernel(efi_system_table_t *sys_table_arg,
+					unsigned long *image_addr,
+					unsigned long image_size,
+					unsigned long alloc_size,
+					unsigned long preferred_addr,
+					unsigned long alignment)
+{
+	unsigned long cur_image_addr;
+	unsigned long new_addr = 0;
+	efi_status_t status;
+	unsigned long nr_pages;
+	efi_physical_addr_t efi_addr = preferred_addr;
+
+	if (!image_addr || !image_size || !alloc_size)
+		return EFI_INVALID_PARAMETER;
+	if (alloc_size < image_size)
+		return EFI_INVALID_PARAMETER;
+
+	cur_image_addr = *image_addr;
+
+	/*
+	 * The EFI firmware loader could have placed the kernel image
+	 * anywhere in memory, but the kernel has restrictions on the
+	 * max physical address it can run at.  Some architectures
+	 * also have a prefered address, so first try to relocate
+	 * to the preferred address.  If that fails, allocate as low
+	 * as possible while respecting the required alignment.
+	 */
+	nr_pages = round_up(alloc_size, EFI_PAGE_SIZE) / EFI_PAGE_SIZE;
+	status = efi_call_phys4(sys_table_arg->boottime->allocate_pages,
+				EFI_ALLOCATE_ADDRESS, EFI_LOADER_DATA,
+				nr_pages, &efi_addr);
+	new_addr = efi_addr;
+	/*
+	 * If preferred address allocation failed allocate as low as
+	 * possible.
+	 */
+	if (status != EFI_SUCCESS) {
+		status = efi_low_alloc(sys_table_arg, alloc_size, alignment,
+				       &new_addr);
+	}
+	if (status != EFI_SUCCESS) {
+		efi_printk(sys_table_arg, "ERROR: Failed to allocate usable memory for kernel.\n");
+		return status;
+	}
+
+	/*
+	 * We know source/dest won't overlap since both memory ranges
+	 * have been allocated by UEFI, so we can safely use memcpy.
+	 */
+	memcpy((void *)new_addr, (void *)cur_image_addr, image_size);
+
+	/* Return the new address of the relocated image. */
+	*image_addr = new_addr;
+
+	return status;
+}
+
+/*
+ * Convert the unicode UEFI command line to ASCII to pass to kernel.
+ * Size of memory allocated return in *cmd_line_len.
+ * Returns NULL on error.
+ */
+static char *efi_convert_cmdline_to_ascii(efi_system_table_t *sys_table_arg,
+				      efi_loaded_image_t *image,
+				      int *cmd_line_len)
+{
+	u16 *s2;
+	u8 *s1 = NULL;
+	unsigned long cmdline_addr = 0;
+	int load_options_size = image->load_options_size / 2; /* ASCII */
+	void *options = image->load_options;
+	int options_size = 0;
+	efi_status_t status;
+	int i;
+	u16 zero = 0;
+
+	if (options) {
+		s2 = options;
+		while (*s2 && *s2 != '\n' && options_size < load_options_size) {
+			s2++;
+			options_size++;
+		}
+	}
+
+	if (options_size == 0) {
+		/* No command line options, so return empty string*/
+		options_size = 1;
+		options = &zero;
+	}
+
+	options_size++;  /* NUL termination */
+#ifdef CONFIG_ARM
+	/*
+	 * For ARM, allocate at a high address to avoid reserved
+	 * regions at low addresses that we don't know the specfics of
+	 * at the time we are processing the command line.
+	 */
+	status = efi_high_alloc(sys_table_arg, options_size, 0,
+			    &cmdline_addr, 0xfffff000);
+#else
+	status = efi_low_alloc(sys_table_arg, options_size, 0,
+			    &cmdline_addr);
+#endif
+	if (status != EFI_SUCCESS)
+		return NULL;
+
+	s1 = (u8 *)cmdline_addr;
+	s2 = (u16 *)options;
+
+	for (i = 0; i < options_size - 1; i++)
+		*s1++ = *s2++;
+
+	*s1 = '\0';
+
+	*cmd_line_len = options_size;
+	return (char *)cmdline_addr;
+}
diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c
index 5145fa344ad..2e2fbdec084 100644
--- a/drivers/firmware/efi/efi.c
+++ b/drivers/firmware/efi/efi.c
@@ -13,11 +13,27 @@
  * This file is released under the GPLv2.
  */
 
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
 #include <linux/kobject.h>
 #include <linux/module.h>
 #include <linux/init.h>
 #include <linux/device.h>
 #include <linux/efi.h>
+#include <linux/io.h>
+
+struct efi __read_mostly efi = {
+	.mps        = EFI_INVALID_TABLE_ADDR,
+	.acpi       = EFI_INVALID_TABLE_ADDR,
+	.acpi20     = EFI_INVALID_TABLE_ADDR,
+	.smbios     = EFI_INVALID_TABLE_ADDR,
+	.sal_systab = EFI_INVALID_TABLE_ADDR,
+	.boot_info  = EFI_INVALID_TABLE_ADDR,
+	.hcdp       = EFI_INVALID_TABLE_ADDR,
+	.uga        = EFI_INVALID_TABLE_ADDR,
+	.uv_systab  = EFI_INVALID_TABLE_ADDR,
+};
+EXPORT_SYMBOL(efi);
 
 static struct kobject *efi_kobj;
 static struct kobject *efivars_kobj;
@@ -132,3 +148,127 @@ err_put:
 }
 
 subsys_initcall(efisubsys_init);
+
+
+/*
+ * We can't ioremap data in EFI boot services RAM, because we've already mapped
+ * it as RAM.  So, look it up in the existing EFI memory map instead.  Only
+ * callable after efi_enter_virtual_mode and before efi_free_boot_services.
+ */
+void __iomem *efi_lookup_mapped_addr(u64 phys_addr)
+{
+	struct efi_memory_map *map;
+	void *p;
+	map = efi.memmap;
+	if (!map)
+		return NULL;
+	if (WARN_ON(!map->map))
+		return NULL;
+	for (p = map->map; p < map->map_end; p += map->desc_size) {
+		efi_memory_desc_t *md = p;
+		u64 size = md->num_pages << EFI_PAGE_SHIFT;
+		u64 end = md->phys_addr + size;
+		if (!(md->attribute & EFI_MEMORY_RUNTIME) &&
+		    md->type != EFI_BOOT_SERVICES_CODE &&
+		    md->type != EFI_BOOT_SERVICES_DATA)
+			continue;
+		if (!md->virt_addr)
+			continue;
+		if (phys_addr >= md->phys_addr && phys_addr < end) {
+			phys_addr += md->virt_addr - md->phys_addr;
+			return (__force void __iomem *)(unsigned long)phys_addr;
+		}
+	}
+	return NULL;
+}
+
+static __initdata efi_config_table_type_t common_tables[] = {
+	{ACPI_20_TABLE_GUID, "ACPI 2.0", &efi.acpi20},
+	{ACPI_TABLE_GUID, "ACPI", &efi.acpi},
+	{HCDP_TABLE_GUID, "HCDP", &efi.hcdp},
+	{MPS_TABLE_GUID, "MPS", &efi.mps},
+	{SAL_SYSTEM_TABLE_GUID, "SALsystab", &efi.sal_systab},
+	{SMBIOS_TABLE_GUID, "SMBIOS", &efi.smbios},
+	{UGA_IO_PROTOCOL_GUID, "UGA", &efi.uga},
+	{NULL_GUID, NULL, 0},
+};
+
+static __init int match_config_table(efi_guid_t *guid,
+				     unsigned long table,
+				     efi_config_table_type_t *table_types)
+{
+	u8 str[EFI_VARIABLE_GUID_LEN + 1];
+	int i;
+
+	if (table_types) {
+		efi_guid_unparse(guid, str);
+
+		for (i = 0; efi_guidcmp(table_types[i].guid, NULL_GUID); i++) {
+			efi_guid_unparse(&table_types[i].guid, str);
+
+			if (!efi_guidcmp(*guid, table_types[i].guid)) {
+				*(table_types[i].ptr) = table;
+				pr_cont(" %s=0x%lx ",
+					table_types[i].name, table);
+				return 1;
+			}
+		}
+	}
+
+	return 0;
+}
+
+int __init efi_config_init(efi_config_table_type_t *arch_tables)
+{
+	void *config_tables, *tablep;
+	int i, sz;
+
+	if (efi_enabled(EFI_64BIT))
+		sz = sizeof(efi_config_table_64_t);
+	else
+		sz = sizeof(efi_config_table_32_t);
+
+	/*
+	 * Let's see what config tables the firmware passed to us.
+	 */
+	config_tables = early_memremap(efi.systab->tables,
+				       efi.systab->nr_tables * sz);
+	if (config_tables == NULL) {
+		pr_err("Could not map Configuration table!\n");
+		return -ENOMEM;
+	}
+
+	tablep = config_tables;
+	pr_info("");
+	for (i = 0; i < efi.systab->nr_tables; i++) {
+		efi_guid_t guid;
+		unsigned long table;
+
+		if (efi_enabled(EFI_64BIT)) {
+			u64 table64;
+			guid = ((efi_config_table_64_t *)tablep)->guid;
+			table64 = ((efi_config_table_64_t *)tablep)->table;
+			table = table64;
+#ifndef CONFIG_64BIT
+			if (table64 >> 32) {
+				pr_cont("\n");
+				pr_err("Table located above 4GB, disabling EFI.\n");
+				early_iounmap(config_tables,
+					       efi.systab->nr_tables * sz);
+				return -EINVAL;
+			}
+#endif
+		} else {
+			guid = ((efi_config_table_32_t *)tablep)->guid;
+			table = ((efi_config_table_32_t *)tablep)->table;
+		}
+
+		if (!match_config_table(&guid, table, common_tables))
+			match_config_table(&guid, table, arch_tables);
+
+		tablep += sz;
+	}
+	pr_cont("\n");
+	early_iounmap(config_tables, efi.systab->nr_tables * sz);
+	return 0;
+}
diff --git a/drivers/firmware/efi/efivars.c b/drivers/firmware/efi/efivars.c
index 8a7432a4b41..933eb027d52 100644
--- a/drivers/firmware/efi/efivars.c
+++ b/drivers/firmware/efi/efivars.c
@@ -564,7 +564,7 @@ static int efivar_sysfs_destroy(struct efivar_entry *entry, void *data)
 	return 0;
 }
 
-void efivars_sysfs_exit(void)
+static void efivars_sysfs_exit(void)
 {
 	/* Remove all entries and destroy */
 	__efivar_entry_iter(efivar_sysfs_destroy, &efivar_sysfs_list, NULL, NULL);