[PATCH 5.15 369/530] powerpc/64s: Fix GENERIC_CPU build flags for PPC970 / G5

From: Greg Kroah-Hartman
Date: Mon Oct 24 2022 - 10:25:37 EST


From: Nicholas Piggin <npiggin@xxxxxxxxx>

[ Upstream commit 58ec7f06b74e0d6e76c4110afce367c8b5f0837d ]

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: 471d7ff8b51b ("powerpc/64s: Remove POWER4 support")
Signed-off-by: Nicholas Piggin <npiggin@xxxxxxxxx>
Reviewed-by: Segher Boessenkool <segher@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20220921014103.587954-1-npiggin@xxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
arch/powerpc/Makefile | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/powerpc/Makefile b/arch/powerpc/Makefile
index 2bb0fe9b2058..7859ae56fcdc 100644
--- a/arch/powerpc/Makefile
+++ b/arch/powerpc/Makefile
@@ -154,7 +154,7 @@ 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
--
2.35.1