85xx: Add basic e500mc core support

Introduce CONFIG_E500MC to deal with the minor differences between
e500v2 and e500mc.

* Certain fields of HID0/1 don't exist anymore on e500mc
* Cache line size is 64-bytes on e500mc
* reset value of PIR is different

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
diff --git a/cpu/mpc85xx/release.S b/cpu/mpc85xx/release.S
index ec5e4da..7c3e8a1 100644
--- a/cpu/mpc85xx/release.S
+++ b/cpu/mpc85xx/release.S
@@ -24,14 +24,18 @@
 __secondary_start_page:
 /* First do some preliminary setup */
 	lis	r3, HID0_EMCP@h		/* enable machine check */
+#ifndef CONFIG_E500MC
 	ori	r3,r3,HID0_TBEN@l	/* enable Timebase */
+#endif
 #ifdef CONFIG_PHYS_64BIT
 	ori	r3,r3,HID0_ENMAS7@l	/* enable MAS7 updates */
 #endif
 	mtspr	SPRN_HID0,r3
 
+#ifndef CONFIG_E500MC
 	li	r3,(HID1_ASTME|HID1_ABE)@l	/* Addr streaming & broadcast */
 	mtspr	SPRN_HID1,r3
+#endif
 
 	/* Enable branch prediction */
 	li	r3,0x201
@@ -64,7 +68,11 @@
 
 	/* r10 has the base address for the entry */
 	mfspr	r0,SPRN_PIR
+#ifdef CONFIG_E500MC
+	rlwinm	r4,r0,27,27,31
+#else
 	mr	r4,r0
+#endif
 	slwi	r8,r4,5
 	add	r10,r3,r8