powerpc/boot: Disable power10 features after BOOTAFLAGS assignment

[ Upstream commit 2b694fc96fe33a7c042e3a142d27d945c8c668b0 ]

When building the boot wrapper assembly files with clang after
commit 648a1783fe25 ("powerpc/boot: Fix boot wrapper code generation
with CONFIG_POWER10_CPU"), the following warnings appear for each file
built:

  '-prefixed' is not a recognized feature for this target (ignoring feature)
  '-pcrel' is not a recognized feature for this target (ignoring feature)

While it is questionable whether or not LLVM should be emitting a
warning when passed negative versions of code generation flags when
building assembly files (since it does not emit a warning for the
altivec and vsx flags), it is easy enough to work around this by just
moving the disabled flags to BOOTCFLAGS after the assignment of
BOOTAFLAGS, so that they are not added when building assembly files.
Do so to silence the warnings.

Fixes: 648a1783fe25 ("powerpc/boot: Fix boot wrapper code generation with CONFIG_POWER10_CPU")
Link: https://github.com/ClangBuiltLinux/linux/issues/1839
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230427-remove-power10-args-from-boot-aflags-clang-v1-1-9107f7c943bc@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/arch/powerpc/boot/Makefile b/arch/powerpc/boot/Makefile
index 13fad4f0a6d8fbc933c9abc8496eec3eb5bdf357..b13324b1a1696ffe9b57d32d83d417365a8ec6d0 100644 (file)
--- a/arch/powerpc/boot/Makefile
+++ b/arch/powerpc/boot/Makefile
@@ -34,8 +34,6 @@ endif
 
 BOOTCFLAGS    := -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs \
                 -fno-strict-aliasing -O2 -msoft-float -mno-altivec -mno-vsx \
-                $(call cc-option,-mno-prefixed) $(call cc-option,-mno-pcrel) \
-                $(call cc-option,-mno-mma) \
                 $(call cc-option,-mno-spe) $(call cc-option,-mspe=no) \
                 -pipe -fomit-frame-pointer -fno-builtin -fPIC -nostdinc \
                 $(LINUXINCLUDE)
@@ -71,6 +69,10 @@ BOOTAFLAGS   := -D__ASSEMBLY__ $(BOOTCFLAGS) -nostdinc
 
 BOOTARFLAGS    := -crD
 
+BOOTCFLAGS     += $(call cc-option,-mno-prefixed) \
+                  $(call cc-option,-mno-pcrel) \
+                  $(call cc-option,-mno-mma)
+
 ifdef CONFIG_CC_IS_CLANG
 BOOTCFLAGS += $(CLANG_FLAGS)
 BOOTAFLAGS += $(CLANG_FLAGS)