powerpc: Add POWER8 CPU selection

This allows the user to build a kernel targeted at POWER8
(ie gcc -mcpu=power8).

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
diff --git a/arch/powerpc/Makefile b/arch/powerpc/Makefile
index 5687e29..132d9c6 100644
--- a/arch/powerpc/Makefile
+++ b/arch/powerpc/Makefile
@@ -135,6 +135,7 @@
 CFLAGS-$(CONFIG_POWER5_CPU) += $(call cc-option,-mcpu=power5)
 CFLAGS-$(CONFIG_POWER6_CPU) += $(call cc-option,-mcpu=power6)
 CFLAGS-$(CONFIG_POWER7_CPU) += $(call cc-option,-mcpu=power7)
+CFLAGS-$(CONFIG_POWER8_CPU) += $(call cc-option,-mcpu=power8)
 
 # Altivec option not allowed with e500mc64 in GCC.
 ifeq ($(CONFIG_ALTIVEC),y)
diff --git a/arch/powerpc/platforms/Kconfig.cputype b/arch/powerpc/platforms/Kconfig.cputype
index e8bc408..26703be 100644
--- a/arch/powerpc/platforms/Kconfig.cputype
+++ b/arch/powerpc/platforms/Kconfig.cputype
@@ -117,6 +117,10 @@
 	bool "POWER7"
 	depends on PPC_BOOK3S_64
 
+config POWER8_CPU
+	bool "POWER8"
+	depends on PPC_BOOK3S_64
+
 config E5500_CPU
 	bool "Freescale e5500"
 	depends on E500