[PATCH] arm: set alignment properly for asm funcs

[PATCH] arm: set alignment properly for asm funcs

[Sam Edwards]

ARM requires a 4-byte alignment on all ARM code (though this
requirement is relaxed to 2-byte for some THUMB code) and we
should be explicit about that here.

GAS has its own fix for this[1] that forces proper alignment
on any section containing assembled instructions, but this is
not universal: Clang's and other gaslike assemblers lack this
implicit alignment. Whether or not this is considered a bug in
those assemblers, it is better to ask directly for what we want.

[1]: https://sourceware.org/bugzilla/show_bug.cgi?id=12931

Signed-off-by: Sam Edwards <CFSworks@gmail.com>
---
 arch/arm/include/asm/linkage.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/arm/include/asm/linkage.h b/arch/arm/include/asm/linkage.h
index dbe4b4e31a..73bf25ba4e 100644
--- a/arch/arm/include/asm/linkage.h
+++ b/arch/arm/include/asm/linkage.h
@@ -1,7 +1,7 @@
 #ifndef __ASM_LINKAGE_H
 #define __ASM_LINKAGE_H
 
-#define __ALIGN .align 0
-#define __ALIGN_STR ".align 0"
+#define __ALIGN .p2align 2
+#define __ALIGN_STR ".p2align 2"
 
 #endif
-- 
2.39.2

Re: [PATCH] arm: set alignment properly for asm funcs

[Tom Rini]

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On Fri, May 12, 2023 at 04:31:05PM -0600, Sam Edwards wrote:

> ARM requires a 4-byte alignment on all ARM code (though this
> requirement is relaxed to 2-byte for some THUMB code) and we
> should be explicit about that here.
> 
> GAS has its own fix for this[1] that forces proper alignment
> on any section containing assembled instructions, but this is
> not universal: Clang's and other gaslike assemblers lack this
> implicit alignment. Whether or not this is considered a bug in
> those assemblers, it is better to ask directly for what we want.
> 
> [1]: https://sourceware.org/bugzilla/show_bug.cgi?id=12931
> 
> Signed-off-by: Sam Edwards <CFSworks@gmail.com>

Applied to u-boot/next, thanks!

-- 
Tom

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