efi.h: Do not use config options

Currently efi.h determines a few bits of its environment according to
config options. This falls apart with the efi stub support which may
result in efi.h getting pulled into the stub as well as real U-Boot
code. In that case, one may be 32bit while the other one is 64bit.

This patch changes the conditionals to use compiler provided defines
instead. That way we always adhere to the build environment we're in
and the definitions adjust automatically.

Signed-off-by: Alexander Graf <agraf@suse.de>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Tested-by: Bin Meng <bmeng.cn@gmail.com>
[bmeng: added some comments to describe the __x86_64__ check]
Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

include/efi.h

@@ -19,12 +19,19 @@
 #include <linux/string.h>
 #include <linux/types.h>
 
-#if CONFIG_EFI_STUB_64BIT || (!defined(CONFIG_EFI_STUB) && defined(__x86_64__))
-/* EFI uses the Microsoft ABI which is not the default for GCC */
+/*
+ * EFI on x86_64 uses the Microsoft ABI which is not the default for GCC.
+ *
+ * There are two scenarios for EFI on x86_64: building a 64-bit EFI stub
+ * codes (CONFIG_EFI_STUB_64BIT) and building a 64-bit U-Boot (CONFIG_X86_64).
+ * Either needs to be properly built with the '-m64' compiler flag, and hence
+ * it is enough to only check the compiler provided define __x86_64__ here.
+ */
+#ifdef __x86_64__
 #define EFIAPI __attribute__((ms_abi))
 #else
 #define EFIAPI asmlinkage
-#endif
+#endif /* __x86_64__ */
 
 struct efi_device_path;
 
@@ -32,16 +39,7 @@ typedef struct {
 	u8 b[16];
 } efi_guid_t;
 
-#define EFI_BITS_PER_LONG	BITS_PER_LONG
-
-/*
- * With 64-bit EFI stub, EFI_BITS_PER_LONG has to be 64. EFI_STUB is set
- * in lib/efi/Makefile, when building the stub.
- */
-#if defined(CONFIG_EFI_STUB_64BIT) && defined(EFI_STUB)
-#undef EFI_BITS_PER_LONG
-#define EFI_BITS_PER_LONG	64
-#endif
+#define EFI_BITS_PER_LONG	(sizeof(long) * 8)
 
 /* Bit mask for EFI status code with error */
 #define EFI_ERROR_MASK (1UL << (EFI_BITS_PER_LONG - 1))

lib/efi/Makefile

@@ -7,11 +7,11 @@ obj-$(CONFIG_EFI_STUB) += efi_info.o
 
 CFLAGS_REMOVE_efi_stub.o := -mregparm=3 \
 	$(if $(CONFIG_EFI_STUB_64BIT),-march=i386 -m32)
-CFLAGS_efi_stub.o := -fpic -fshort-wchar -DEFI_STUB \
+CFLAGS_efi_stub.o := -fpic -fshort-wchar \
 	$(if $(CONFIG_EFI_STUB_64BIT),-m64)
 CFLAGS_REMOVE_efi.o := -mregparm=3 \
 	$(if $(CONFIG_EFI_STUB_64BIT),-march=i386 -m32)
-CFLAGS_efi.o := -fpic -fshort-wchar -DEFI_STUB \
+CFLAGS_efi.o := -fpic -fshort-wchar \
 	$(if $(CONFIG_EFI_STUB_64BIT),-m64)
 
 extra-$(CONFIG_EFI_STUB) += efi_stub.o efi.o