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efi: use 32-bit alignment for efi_guid_t 

Current U-Boot implements 64-bit boundary for efi_guid_t structure.
It follows the UEFI specification, page 21 of the UEFI Specification v2.10
says about EFI_GUID:
  128-bit buffer containing a unique identifier value. Unless
  otherwise specified, aligned on a 64-bit boundary.

On the other hand, page 163 of the UEFI specification v2.10 and
EDK2 reference implementation both define EFI_GUID as
struct { u32 a; u16; b; u16 c; u8 d[8]; }; and so the implied
alignment is 32-bit not 64-bit like U-Boot efi_guid_t.

Due to this alignment difference, EDK2 application "CapsuleApp.efi -P"
does not work as expected.
This calls EFI_FIRMWARE_MANAGEMENT_PROTOCOL.GetImageInfo()
and dump the EFI_FIRMWARE_IMAGE_DESCRIPTOR structure,
offsetof(EFI_FIRMWARE_IMAGE_DESCRIPTOR, ImageTypeId) is different,
8 in U-Boot and 4 in EDK2(CapsuleApp.efi).
Here is the wrong EFI_GUID dump.
  wrong dump : ImageTypeId - 00000000-7D83-058B-D550-474CA19560D8
  expected   : ImageTypeId - 058B7D83-50D5-4C47-A195-60D86AD341C4

EFI_FIRMWARE_IMAGE_DESCRIPTOR structure is defined in UEFI specification:
  typedef struct {
          UINT8 ImageIndex;
          EFI_GUID ImageTypeId;
          UINT64 ImageId
          <snip>

  } EFI_FIRMWARE_IMAGE_DESCRIPTOR;

There was the relevant patch for linux kernel to use 32-bit alignment
for efi_guid_t [1].
U-Boot should get aligned to EDK2 reference implementation and
linux kernel.

Due to this alignment change, efi_hii_ref structure in include/efi_api.h
is affected, but it is not used in the current U-Boot code.

[1] https://lore.kernel.org/all/20190202094119.13230-5-ard.biesheuvel@linaro.org/

Cc: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Signed-off-by: Masahisa Kojima <masahisa.kojima@linaro.org>
Reviewed-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
This commit is contained in:
Masahisa Kojima 2023-01-28 13:56:14 +09:00 committed by Heinrich Schuchardt
parent 8ad7cfec37
commit 1dd705cf99
1 changed files with 10 additions and 1 deletions
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11
include/efi.h
View File

@ -54,9 +54,18 @@
struct efi_device_path;
/*
* The EFI spec defines the EFI_GUID as
* "128-bit buffer containing a unique identifier value. Unless otherwise specified,
* aligned on a 64-bit boundary".
* Page 163 of the UEFI specification v2.10 and
* EDK2 reference implementation both define EFI_GUID as
* struct { u32 a; u16; b; u16 c; u8 d[8]; }; which is 4-byte
* aligned.
*/
typedef struct {
u8 b[16];
} efi_guid_t __attribute__((aligned(8)));
} efi_guid_t __attribute__((aligned(4)));
#define EFI_BITS_PER_LONG (sizeof(long) * 8)