[MIPS] Nevada support for SGI O2.

Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

arch/mips/Kconfig

@@ -595,6 +595,7 @@ config SGI_IP32
 	select SYS_HAS_CPU_R5000
 	select SYS_HAS_CPU_R10000 if BROKEN
 	select SYS_HAS_CPU_RM7000
+	select SYS_HAS_CPU_NEVADA
 	select SYS_SUPPORTS_64BIT_KERNEL
 	select SYS_SUPPORTS_BIG_ENDIAN
 	help

arch/mips/configs/ip32_defconfig

@@ -102,6 +102,7 @@ CONFIG_CPU_R5000=y
 # CONFIG_CPU_RM9000 is not set
 # CONFIG_CPU_SB1 is not set
 CONFIG_SYS_HAS_CPU_R5000=y
+CONFIG_SYS_HAS_CPU_NEVADA=y
 CONFIG_SYS_HAS_CPU_RM7000=y
 CONFIG_SYS_SUPPORTS_64BIT_KERNEL=y
 CONFIG_CPU_SUPPORTS_32BIT_KERNEL=y

include/asm-mips/mach-ip32/cpu-feature-overrides.h

@@ -18,7 +18,7 @@
  * so, for 64bit IP32 kernel we just don't use ll/sc.
  * This does not affect luserland.
  */
-#if defined(CONFIG_CPU_R5000) && defined(CONFIG_64BIT)
+#if (defined(CONFIG_CPU_R5000) || defined(CONFIG_CPU_NEVADA)) && defined(CONFIG_64BIT)
 #define cpu_has_llsc		0
 #else
 #define cpu_has_llsc		1