efi: Fix truncation of constant value
Starting with commit 867a6ac86dd8 ("efi: Add start-up library code"),
sparse constantly complains about truncated constant value in efi.h:
include/efi.h:176:35: warning: cast truncates bits from constant value (8000000000000000 becomes 0)
This can get quite noisy, preventing real issues to be noticed:
$ make defconfig
*** Default configuration is based on 'sandbox_defconfig'
$ make C=2 -j12 2>&1 | grep truncates | wc -l
441
After the patch is applied:
$ make C=2 -j12 2>&1 | grep truncates | wc -l
0
$ sparse --version
v0.5.2
Following the suggestion of Heinrich Schuchardt, instead of only
fixing the root-cause, I replaced the whole enum of _SHIFT values
by ULL defines. This matches both the UEFI 2.7 spec and the Linux
kernel implementation.
Some ELF size comparison before and after the patch (gcc 7.3.0):
efi-x86_payload64_defconfig:
text data bss dec hex filename
407174 29432 278676 715282 aea12 u-boot.old
407152 29464 278676 715292 aea1c u-boot.new
-22 +32 0 +10
efi-x86_payload32_defconfig:
text data bss dec hex filename
447075 30308 280076 757459 b8ed3 u-boot.old
447053 30340 280076 757469 b8edd u-boot.new
-22 +32 0 +10
Fixes: 867a6ac86dd8 ("efi: Add start-up library code")
Suggested-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Signed-off-by: Eugeniu Rosca <erosca@de.adit-jv.com>
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Signed-off-by: Alexander Graf <agraf@suse.de>
diff --git a/include/efi.h b/include/efi.h
index 41530a7..cfdccd7 100644
--- a/include/efi.h
+++ b/include/efi.h
@@ -170,20 +170,16 @@
};
/* Attribute values */
-enum {
- EFI_MEMORY_UC_SHIFT = 0, /* uncached */
- EFI_MEMORY_WC_SHIFT = 1, /* write-coalescing */
- EFI_MEMORY_WT_SHIFT = 2, /* write-through */
- EFI_MEMORY_WB_SHIFT = 3, /* write-back */
- EFI_MEMORY_UCE_SHIFT = 4, /* uncached, exported */
- EFI_MEMORY_WP_SHIFT = 12, /* write-protect */
- EFI_MEMORY_RP_SHIFT = 13, /* read-protect */
- EFI_MEMORY_XP_SHIFT = 14, /* execute-protect */
- EFI_MEMORY_RUNTIME_SHIFT = 63, /* range requires runtime mapping */
-
- EFI_MEMORY_RUNTIME = 1ULL << EFI_MEMORY_RUNTIME_SHIFT,
- EFI_MEM_DESC_VERSION = 1,
-};
+#define EFI_MEMORY_UC ((u64)0x0000000000000001ULL) /* uncached */
+#define EFI_MEMORY_WC ((u64)0x0000000000000002ULL) /* write-coalescing */
+#define EFI_MEMORY_WT ((u64)0x0000000000000004ULL) /* write-through */
+#define EFI_MEMORY_WB ((u64)0x0000000000000008ULL) /* write-back */
+#define EFI_MEMORY_UCE ((u64)0x0000000000000010ULL) /* uncached, exported */
+#define EFI_MEMORY_WP ((u64)0x0000000000001000ULL) /* write-protect */
+#define EFI_MEMORY_RP ((u64)0x0000000000002000ULL) /* read-protect */
+#define EFI_MEMORY_XP ((u64)0x0000000000004000ULL) /* execute-protect */
+#define EFI_MEMORY_RUNTIME ((u64)0x8000000000000000ULL) /* range requires runtime mapping */
+#define EFI_MEM_DESC_VERSION 1
#define EFI_PAGE_SHIFT 12
#define EFI_PAGE_SIZE (1UL << EFI_PAGE_SHIFT)