diff mbox

[v2,4/5] efi: efistub: refactor stub components

Message ID 1403792617-25792-5-git-send-email-ard.biesheuvel@linaro.org
State New
Headers show

Commit Message

Ard Biesheuvel June 26, 2014, 2:23 p.m. UTC
In order to move from the #include "../../../xxxxx.c" anti-pattern used by
both the x86 and arm64 versions of the stub to a static library linked into
either the kernel proper (arm64) or a separate boot executable (x86), there
is some prepatory work required.

This patch does the following:
- move forward declarations of functions shared between the arch specific and
  the generic parts of the stub to include/linux/efi.h
- move forward declarations of functions shared between various .c files of the
  generic stub code to a new local header file called "efistub.h"
- add #includes to all .c files which were formerly relying on the #includor to
  include the correct header files
- remove all static modifiers from functions which will need to be externally
  visible once we move to a static library

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
---
 arch/arm64/kernel/efi-stub.c           | 29 ++++---------
 arch/x86/boot/compressed/eboot.c       | 13 +++---
 drivers/firmware/efi/arm-stub.c        | 18 ++++++---
 drivers/firmware/efi/efi-stub-helper.c | 74 +++++++++++++++++-----------------
 drivers/firmware/efi/efistub.h         | 42 +++++++++++++++++++
 drivers/firmware/efi/fdt.c             | 20 +++++----
 include/linux/efi.h                    | 42 +++++++++++++++++++
 7 files changed, 157 insertions(+), 81 deletions(-)
 create mode 100644 drivers/firmware/efi/efistub.h

Comments

Matt Fleming July 1, 2014, 3:11 p.m. UTC | #1
On Thu, 26 Jun, at 04:23:36PM, Ard Biesheuvel wrote:
> In order to move from the #include "../../../xxxxx.c" anti-pattern used by
> both the x86 and arm64 versions of the stub to a static library linked into
> either the kernel proper (arm64) or a separate boot executable (x86), there
> is some prepatory work required.
> 
> This patch does the following:
> - move forward declarations of functions shared between the arch specific and
>   the generic parts of the stub to include/linux/efi.h
> - move forward declarations of functions shared between various .c files of the
>   generic stub code to a new local header file called "efistub.h"
> - add #includes to all .c files which were formerly relying on the #includor to
>   include the correct header files
> - remove all static modifiers from functions which will need to be externally
>   visible once we move to a static library
> 
> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>

[...]

> diff --git a/include/linux/efi.h b/include/linux/efi.h
> index 0ceb816bdfc2..3a64f2f85821 100644
> --- a/include/linux/efi.h
> +++ b/include/linux/efi.h
> @@ -1163,4 +1163,46 @@ static inline void
>  efi_runtime_map_setup(void *map, int nr_entries, u32 desc_size) {}
>  #endif
>  
> +/* prototypes shared between arch specific and generic stub code */
> +
> +#define pr_efi(sys_table, msg)     efi_printk(sys_table, "EFI stub: "msg)
> +#define pr_efi_err(sys_table, msg) efi_printk(sys_table, "EFI stub: ERROR: "msg)
> +
> +void efi_printk(efi_system_table_t *sys_table_arg, char *str);
> +
> +void efi_free(efi_system_table_t *sys_table_arg, unsigned long size,
> +	      unsigned long addr);
> +
> +char *efi_convert_cmdline(efi_system_table_t *sys_table_arg,
> +			  efi_loaded_image_t *image, int *cmd_line_len);
> +

We've been very good so far at not splattering include/linux/efi.h with
any of the EFI boot stub prototypes, and it would be awesome if we
didn't have to start now.

Is there any way we could avoid doing this? Arguably everything should
be in the new efistub.h, no?
Ard Biesheuvel July 1, 2014, 3:18 p.m. UTC | #2
On 1 July 2014 17:11, Matt Fleming <matt@console-pimps.org> wrote:
> On Thu, 26 Jun, at 04:23:36PM, Ard Biesheuvel wrote:
>> In order to move from the #include "../../../xxxxx.c" anti-pattern used by
>> both the x86 and arm64 versions of the stub to a static library linked into
>> either the kernel proper (arm64) or a separate boot executable (x86), there
>> is some prepatory work required.
>>
>> This patch does the following:
>> - move forward declarations of functions shared between the arch specific and
>>   the generic parts of the stub to include/linux/efi.h
>> - move forward declarations of functions shared between various .c files of the
>>   generic stub code to a new local header file called "efistub.h"
>> - add #includes to all .c files which were formerly relying on the #includor to
>>   include the correct header files
>> - remove all static modifiers from functions which will need to be externally
>>   visible once we move to a static library
>>
>> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
>
> [...]
>
>> diff --git a/include/linux/efi.h b/include/linux/efi.h
>> index 0ceb816bdfc2..3a64f2f85821 100644
>> --- a/include/linux/efi.h
>> +++ b/include/linux/efi.h
>> @@ -1163,4 +1163,46 @@ static inline void
>>  efi_runtime_map_setup(void *map, int nr_entries, u32 desc_size) {}
>>  #endif
>>
>> +/* prototypes shared between arch specific and generic stub code */
>> +
>> +#define pr_efi(sys_table, msg)     efi_printk(sys_table, "EFI stub: "msg)
>> +#define pr_efi_err(sys_table, msg) efi_printk(sys_table, "EFI stub: ERROR: "msg)
>> +
>> +void efi_printk(efi_system_table_t *sys_table_arg, char *str);
>> +
>> +void efi_free(efi_system_table_t *sys_table_arg, unsigned long size,
>> +           unsigned long addr);
>> +
>> +char *efi_convert_cmdline(efi_system_table_t *sys_table_arg,
>> +                       efi_loaded_image_t *image, int *cmd_line_len);
>> +
>
> We've been very good so far at not splattering include/linux/efi.h with
> any of the EFI boot stub prototypes, and it would be awesome if we
> didn't have to start now.
>
> Is there any way we could avoid doing this? Arguably everything should
> be in the new efistub.h, no?
>

There are bits that are shared between code under arch/xxx and
drivers/firmware/efi, and what those bits are is different between the
archs. I used <asm/efi.h> just for convenience, but perhaps we could
add <asm/efistub.h> for each arch, and #include it in both "efistub.h"
under drivers/firmware/efi and the stub bits that live under arch/xxx?
Then any other users of <asm/efi.h> won't have to see it.
Ard Biesheuvel July 1, 2014, 3:20 p.m. UTC | #3
On 1 July 2014 17:18, Ard Biesheuvel <ard.biesheuvel@linaro.org> wrote:
> On 1 July 2014 17:11, Matt Fleming <matt@console-pimps.org> wrote:
>> On Thu, 26 Jun, at 04:23:36PM, Ard Biesheuvel wrote:
>>> In order to move from the #include "../../../xxxxx.c" anti-pattern used by
>>> both the x86 and arm64 versions of the stub to a static library linked into
>>> either the kernel proper (arm64) or a separate boot executable (x86), there
>>> is some prepatory work required.
>>>
>>> This patch does the following:
>>> - move forward declarations of functions shared between the arch specific and
>>>   the generic parts of the stub to include/linux/efi.h
>>> - move forward declarations of functions shared between various .c files of the
>>>   generic stub code to a new local header file called "efistub.h"
>>> - add #includes to all .c files which were formerly relying on the #includor to
>>>   include the correct header files
>>> - remove all static modifiers from functions which will need to be externally
>>>   visible once we move to a static library
>>>
>>> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
>>
>> [...]
>>
>>> diff --git a/include/linux/efi.h b/include/linux/efi.h
>>> index 0ceb816bdfc2..3a64f2f85821 100644
>>> --- a/include/linux/efi.h
>>> +++ b/include/linux/efi.h
>>> @@ -1163,4 +1163,46 @@ static inline void
>>>  efi_runtime_map_setup(void *map, int nr_entries, u32 desc_size) {}
>>>  #endif
>>>
>>> +/* prototypes shared between arch specific and generic stub code */
>>> +
>>> +#define pr_efi(sys_table, msg)     efi_printk(sys_table, "EFI stub: "msg)
>>> +#define pr_efi_err(sys_table, msg) efi_printk(sys_table, "EFI stub: ERROR: "msg)
>>> +
>>> +void efi_printk(efi_system_table_t *sys_table_arg, char *str);
>>> +
>>> +void efi_free(efi_system_table_t *sys_table_arg, unsigned long size,
>>> +           unsigned long addr);
>>> +
>>> +char *efi_convert_cmdline(efi_system_table_t *sys_table_arg,
>>> +                       efi_loaded_image_t *image, int *cmd_line_len);
>>> +
>>
>> We've been very good so far at not splattering include/linux/efi.h with
>> any of the EFI boot stub prototypes, and it would be awesome if we
>> didn't have to start now.
>>
>> Is there any way we could avoid doing this? Arguably everything should
>> be in the new efistub.h, no?
>>
>
> There are bits that are shared between code under arch/xxx and
> drivers/firmware/efi, and what those bits are is different between the
> archs. I used <asm/efi.h> just for convenience, but perhaps we could
> add <asm/efistub.h> for each arch, and #include it in both "efistub.h"
> under drivers/firmware/efi and the stub bits that live under arch/xxx?
> Then any other users of <asm/efi.h> won't have to see it.
>

... but that wasn't your question ....

The reason this can't live in "efistub.h" is that it gets included by
bits under arch/xxx
So perhaps moving the local "efistub.h" to <linux/efistub.h> would be
appropriate, yes.
Matt Fleming July 1, 2014, 4:22 p.m. UTC | #4
On Tue, 01 Jul, at 05:20:21PM, Ard Biesheuvel wrote:
> 
> ... but that wasn't your question ....
> 
> The reason this can't live in "efistub.h" is that it gets included by
> bits under arch/xxx
> So perhaps moving the local "efistub.h" to <linux/efistub.h> would be
> appropriate, yes.

I didn't mean that we should add include/linux/efistub.h, rather that we
should try adding them to efistub.h or asm/efi.h.

But I see that isn't going to work too well and there's no easy fix.
Let's just leave things as they are for now.

Long term, I've been thinking of splitting up include/linux/efi.h. It's
currently weighing in at 1208 lines and contains pieces for all sorts of
different chunks of EFI code, 32-bit and 64-bit versions of data
structures, etc.
diff mbox

Patch

diff --git a/arch/arm64/kernel/efi-stub.c b/arch/arm64/kernel/efi-stub.c
index 23cbde4324b1..e4999021b07d 100644
--- a/arch/arm64/kernel/efi-stub.c
+++ b/arch/arm64/kernel/efi-stub.c
@@ -11,36 +11,21 @@ 
  */
 #include <linux/efi.h>
 #include <asm/efi.h>
-#include <linux/libfdt.h>
 #include <asm/sections.h>
 
-static void efi_char16_printk(efi_system_table_t *sys_table_arg,
-			      efi_char16_t *str);
-
-static efi_status_t efi_open_volume(efi_system_table_t *sys_table,
-				    void *__image, void **__fh);
-static efi_status_t efi_file_close(void *handle);
-
-static efi_status_t
-efi_file_read(void *handle, unsigned long *size, void *addr);
-
-static efi_status_t
-efi_file_size(efi_system_table_t *sys_table, void *__fh,
-	      efi_char16_t *filename_16, void **handle, u64 *file_sz);
-
 /* Include shared EFI stub code */
 #include "../../../drivers/firmware/efi/efi-stub-helper.c"
 #include "../../../drivers/firmware/efi/fdt.c"
 #include "../../../drivers/firmware/efi/arm-stub.c"
 
 
-static efi_status_t handle_kernel_image(efi_system_table_t *sys_table,
-					unsigned long *image_addr,
-					unsigned long *image_size,
-					unsigned long *reserve_addr,
-					unsigned long *reserve_size,
-					unsigned long dram_base,
-					efi_loaded_image_t *image)
+efi_status_t handle_kernel_image(efi_system_table_t *sys_table,
+				 unsigned long *image_addr,
+				 unsigned long *image_size,
+				 unsigned long *reserve_addr,
+				 unsigned long *reserve_size,
+				 unsigned long dram_base,
+				 efi_loaded_image_t *image)
 {
 	efi_status_t status;
 	unsigned long kernel_size, kernel_memsize = 0;
diff --git a/arch/x86/boot/compressed/eboot.c b/arch/x86/boot/compressed/eboot.c
index 2fd5e2643623..d338c134c659 100644
--- a/arch/x86/boot/compressed/eboot.c
+++ b/arch/x86/boot/compressed/eboot.c
@@ -45,8 +45,7 @@  static void setup_boot_services##bits(struct efi_config *c)		\
 BOOT_SERVICES(32);
 BOOT_SERVICES(64);
 
-static void efi_printk(efi_system_table_t *, char *);
-static void efi_char16_printk(efi_system_table_t *, efi_char16_t *);
+void efi_char16_printk(efi_system_table_t *, efi_char16_t *);
 
 static efi_status_t
 __file_size32(void *__fh, efi_char16_t *filename_16,
@@ -153,7 +152,7 @@  grow:
 
 	return status;
 }
-static efi_status_t
+efi_status_t
 efi_file_size(efi_system_table_t *sys_table, void *__fh,
 	      efi_char16_t *filename_16, void **handle, u64 *file_sz)
 {
@@ -163,7 +162,7 @@  efi_file_size(efi_system_table_t *sys_table, void *__fh,
 	return __file_size32(__fh, filename_16, handle, file_sz);
 }
 
-static inline efi_status_t
+efi_status_t
 efi_file_read(void *handle, unsigned long *size, void *addr)
 {
 	unsigned long func;
@@ -181,7 +180,7 @@  efi_file_read(void *handle, unsigned long *size, void *addr)
 	}
 }
 
-static inline efi_status_t efi_file_close(void *handle)
+efi_status_t efi_file_close(void *handle)
 {
 	if (efi_early->is64) {
 		efi_file_handle_64_t *fh = handle;
@@ -246,7 +245,7 @@  static inline efi_status_t __open_volume64(void *__image, void **__fh)
 	return status;
 }
 
-static inline efi_status_t
+efi_status_t
 efi_open_volume(efi_system_table_t *sys_table, void *__image, void **__fh)
 {
 	if (efi_early->is64)
@@ -255,7 +254,7 @@  efi_open_volume(efi_system_table_t *sys_table, void *__image, void **__fh)
 	return __open_volume32(__image, __fh);
 }
 
-static void efi_char16_printk(efi_system_table_t *table, efi_char16_t *str)
+void efi_char16_printk(efi_system_table_t *table, efi_char16_t *str)
 {
 	unsigned long output_string;
 	size_t offset;
diff --git a/drivers/firmware/efi/arm-stub.c b/drivers/firmware/efi/arm-stub.c
index 41114ce03b01..34614d6f9698 100644
--- a/drivers/firmware/efi/arm-stub.c
+++ b/drivers/firmware/efi/arm-stub.c
@@ -12,6 +12,11 @@ 
  *
  */
 
+#include <linux/efi.h>
+#include <asm/efi.h>
+
+#include "efistub.h"
+
 static int __init efi_secureboot_enabled(efi_system_table_t *sys_table_arg)
 {
 	static efi_guid_t const var_guid __initconst = EFI_GLOBAL_VARIABLE_GUID;
@@ -36,8 +41,8 @@  static int __init efi_secureboot_enabled(efi_system_table_t *sys_table_arg)
 	}
 }
 
-static efi_status_t efi_open_volume(efi_system_table_t *sys_table_arg,
-				    void *__image, void **__fh)
+efi_status_t efi_open_volume(efi_system_table_t *sys_table_arg,
+			     void *__image, void **__fh)
 {
 	efi_file_io_interface_t *io;
 	efi_loaded_image_t *image = __image;
@@ -60,14 +65,15 @@  static efi_status_t efi_open_volume(efi_system_table_t *sys_table_arg,
 	*__fh = fh;
 	return status;
 }
-static efi_status_t efi_file_close(void *handle)
+
+efi_status_t efi_file_close(void *handle)
 {
 	efi_file_handle_t *fh = handle;
 
 	return fh->close(handle);
 }
 
-static efi_status_t
+efi_status_t
 efi_file_read(void *handle, unsigned long *size, void *addr)
 {
 	efi_file_handle_t *fh = handle;
@@ -76,7 +82,7 @@  efi_file_read(void *handle, unsigned long *size, void *addr)
 }
 
 
-static efi_status_t
+efi_status_t
 efi_file_size(efi_system_table_t *sys_table_arg, void *__fh,
 	      efi_char16_t *filename_16, void **handle, u64 *file_sz)
 {
@@ -129,7 +135,7 @@  grow:
 
 
 
-static void efi_char16_printk(efi_system_table_t *sys_table_arg,
+void efi_char16_printk(efi_system_table_t *sys_table_arg,
 			      efi_char16_t *str)
 {
 	struct efi_simple_text_output_protocol *out;
diff --git a/drivers/firmware/efi/efi-stub-helper.c b/drivers/firmware/efi/efi-stub-helper.c
index eb6d4be9e722..32d5cca30f49 100644
--- a/drivers/firmware/efi/efi-stub-helper.c
+++ b/drivers/firmware/efi/efi-stub-helper.c
@@ -9,18 +9,20 @@ 
  * under the terms of the GNU General Public License version 2.
  *
  */
-#define EFI_READ_CHUNK_SIZE	(1024 * 1024)
 
-/* error code which can't be mistaken for valid address */
-#define EFI_ERROR	(~0UL)
+#include <linux/efi.h>
+#include <asm/efi.h>
+
+#include "efistub.h"
 
+#define EFI_READ_CHUNK_SIZE	(1024 * 1024)
 
 struct file_info {
 	efi_file_handle_t *handle;
 	u64 size;
 };
 
-static void efi_printk(efi_system_table_t *sys_table_arg, char *str)
+void efi_printk(efi_system_table_t *sys_table_arg, char *str)
 {
 	char *s8;
 
@@ -37,16 +39,12 @@  static void efi_printk(efi_system_table_t *sys_table_arg, char *str)
 	}
 }
 
-#define pr_efi(sys_table, msg)     efi_printk(sys_table, "EFI stub: "msg)
-#define pr_efi_err(sys_table, msg) efi_printk(sys_table, "EFI stub: ERROR: "msg)
-
-
-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_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;
@@ -88,7 +86,7 @@  fail:
 }
 
 
-static unsigned long __init get_dram_base(efi_system_table_t *sys_table_arg)
+unsigned long __init get_dram_base(efi_system_table_t *sys_table_arg)
 {
 	efi_status_t status;
 	unsigned long map_size;
@@ -116,9 +114,9 @@  static unsigned long __init get_dram_base(efi_system_table_t *sys_table_arg)
 /*
  * 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)
+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;
@@ -202,9 +200,9 @@  fail:
 /*
  * 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)
+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;
@@ -271,8 +269,8 @@  fail:
 	return status;
 }
 
-static void efi_free(efi_system_table_t *sys_table_arg, unsigned long size,
-		     unsigned long addr)
+void efi_free(efi_system_table_t *sys_table_arg, unsigned long size,
+	      unsigned long addr)
 {
 	unsigned long nr_pages;
 
@@ -290,12 +288,12 @@  static void efi_free(efi_system_table_t *sys_table_arg, unsigned long size,
  * 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)
+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;
@@ -477,12 +475,12 @@  fail:
  * 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)
+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;
@@ -589,9 +587,9 @@  static u8 *efi_utf16_to_utf8(u8 *dst, const u16 *src, int n)
  * Size of memory allocated return in *cmd_line_len.
  * Returns NULL on error.
  */
-static char *efi_convert_cmdline(efi_system_table_t *sys_table_arg,
-				 efi_loaded_image_t *image,
-				 int *cmd_line_len)
+char *efi_convert_cmdline(efi_system_table_t *sys_table_arg,
+			  efi_loaded_image_t *image,
+			  int *cmd_line_len)
 {
 	const u16 *s2;
 	u8 *s1 = NULL;
diff --git a/drivers/firmware/efi/efistub.h b/drivers/firmware/efi/efistub.h
new file mode 100644
index 000000000000..304ab295ca1a
--- /dev/null
+++ b/drivers/firmware/efi/efistub.h
@@ -0,0 +1,42 @@ 
+
+#ifndef _DRIVERS_FIRMWARE_EFI_EFISTUB_H
+#define _DRIVERS_FIRMWARE_EFI_EFISTUB_H
+
+/* error code which can't be mistaken for valid address */
+#define EFI_ERROR	(~0UL)
+
+void efi_char16_printk(efi_system_table_t *, efi_char16_t *);
+
+efi_status_t efi_open_volume(efi_system_table_t *sys_table_arg, void *__image,
+			     void **__fh);
+
+efi_status_t efi_file_size(efi_system_table_t *sys_table_arg, void *__fh,
+			   efi_char16_t *filename_16, void **handle,
+			   u64 *file_sz);
+
+efi_status_t efi_file_read(void *handle, unsigned long *size, void *addr);
+
+efi_status_t efi_file_close(void *handle);
+
+unsigned long get_dram_base(efi_system_table_t *sys_table_arg);
+
+efi_status_t update_fdt(efi_system_table_t *sys_table, void *orig_fdt,
+			unsigned long orig_fdt_size,
+			void *fdt, int new_fdt_size, char *cmdline_ptr,
+			u64 initrd_addr, u64 initrd_size,
+			efi_memory_desc_t *memory_map,
+			unsigned long map_size, unsigned long desc_size,
+			u32 desc_ver);
+
+efi_status_t allocate_new_fdt_and_exit_boot(efi_system_table_t *sys_table,
+					    void *handle,
+					    unsigned long *new_fdt_addr,
+					    unsigned long max_addr,
+					    u64 initrd_addr, u64 initrd_size,
+					    char *cmdline_ptr,
+					    unsigned long fdt_addr,
+					    unsigned long fdt_size);
+
+void *get_fdt(efi_system_table_t *sys_table);
+
+#endif
diff --git a/drivers/firmware/efi/fdt.c b/drivers/firmware/efi/fdt.c
index 507a3df46a5d..a56bb3528755 100644
--- a/drivers/firmware/efi/fdt.c
+++ b/drivers/firmware/efi/fdt.c
@@ -10,13 +10,17 @@ 
  *
  */
 
-static efi_status_t update_fdt(efi_system_table_t *sys_table, void *orig_fdt,
-			       unsigned long orig_fdt_size,
-			       void *fdt, int new_fdt_size, char *cmdline_ptr,
-			       u64 initrd_addr, u64 initrd_size,
-			       efi_memory_desc_t *memory_map,
-			       unsigned long map_size, unsigned long desc_size,
-			       u32 desc_ver)
+#include <linux/efi.h>
+#include <linux/libfdt.h>
+#include <asm/efi.h>
+
+efi_status_t update_fdt(efi_system_table_t *sys_table, void *orig_fdt,
+			unsigned long orig_fdt_size,
+			void *fdt, int new_fdt_size, char *cmdline_ptr,
+			u64 initrd_addr, u64 initrd_size,
+			efi_memory_desc_t *memory_map,
+			unsigned long map_size, unsigned long desc_size,
+			u32 desc_ver)
 {
 	int node, prev;
 	int status;
@@ -255,7 +259,7 @@  fail:
 	return EFI_LOAD_ERROR;
 }
 
-static void *get_fdt(efi_system_table_t *sys_table)
+void *get_fdt(efi_system_table_t *sys_table)
 {
 	efi_guid_t fdt_guid = DEVICE_TREE_GUID;
 	efi_config_table_t *tables;
diff --git a/include/linux/efi.h b/include/linux/efi.h
index 0ceb816bdfc2..3a64f2f85821 100644
--- a/include/linux/efi.h
+++ b/include/linux/efi.h
@@ -1163,4 +1163,46 @@  static inline void
 efi_runtime_map_setup(void *map, int nr_entries, u32 desc_size) {}
 #endif
 
+/* prototypes shared between arch specific and generic stub code */
+
+#define pr_efi(sys_table, msg)     efi_printk(sys_table, "EFI stub: "msg)
+#define pr_efi_err(sys_table, msg) efi_printk(sys_table, "EFI stub: ERROR: "msg)
+
+void efi_printk(efi_system_table_t *sys_table_arg, char *str);
+
+void efi_free(efi_system_table_t *sys_table_arg, unsigned long size,
+	      unsigned long addr);
+
+char *efi_convert_cmdline(efi_system_table_t *sys_table_arg,
+			  efi_loaded_image_t *image, int *cmd_line_len);
+
+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_status_t efi_low_alloc(efi_system_table_t *sys_table_arg,
+			   unsigned long size, unsigned long align,
+			   unsigned long *addr);
+
+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);
+
+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);
+
+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);
+
 #endif /* _LINUX_EFI_H */