powerpc/64s: Fix GENERIC_CPU build flags for PPC970 / G5

[ Upstream commit 5ffbc6112c348dcc3957da2d529eb530dbecc0d5 ]

Big-endian GENERIC_CPU supports 970, but builds with -mcpu=power5.
POWER5 is ISA v2.02 whereas 970 is v2.01 plus Altivec. 2.02 added
the popcntb instruction which a compiler might use.

Use -mcpu=power4.

Fixes: 3dbb88474178 ("powerpc/64s: Remove POWER4 support")
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Segher Boessenkool <segher@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220921014103.587954-1-npiggin@gmail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/arch/powerpc/Makefile b/arch/powerpc/Makefile
index eedd114a017c7ff0aa68a6ddc73c05e8b0237171..95183a717eb67e7fd9ec2ee36907dec2a9544f7f 100644 (file)
--- a/arch/powerpc/Makefile
+++ b/arch/powerpc/Makefile
@@ -155,7 +155,7 @@ CFLAGS-$(CONFIG_GENERIC_CPU) += -mcpu=power8
 CFLAGS-$(CONFIG_GENERIC_CPU) += $(call cc-option,-mtune=power9,-mtune=power8)
 else
 CFLAGS-$(CONFIG_GENERIC_CPU) += $(call cc-option,-mtune=power7,$(call cc-option,-mtune=power5))
-CFLAGS-$(CONFIG_GENERIC_CPU) += $(call cc-option,-mcpu=power5,-mcpu=power4)
+CFLAGS-$(CONFIG_GENERIC_CPU) += -mcpu=power4
 endif
 else ifdef CONFIG_PPC_BOOK3E_64
 CFLAGS-$(CONFIG_GENERIC_CPU) += -mcpu=powerpc64