powerpc/book3e-64: Add helper function to setup IVORs

Not all 64-bit Book-3E parts will have fixed IVORs so add a function that
cpusetup code can call to setup the base IVORs (0..15) to match the fixed
offsets.  We need to 'or' part of interrupt_base_book3e into the IVORs
since on parts that have them the IVPR doesn't extend as far down.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
diff --git a/arch/powerpc/include/asm/exception-64e.h b/arch/powerpc/include/asm/exception-64e.h
index 94cb3d7..6d53f31 100644
--- a/arch/powerpc/include/asm/exception-64e.h
+++ b/arch/powerpc/include/asm/exception-64e.h
@@ -196,6 +196,10 @@
 #define TLB_MISS_STATS_SAVE_INFO
 #endif
 
+#define SET_IVOR(vector_number, vector_offset)	\
+	li	r3,vector_offset@l; 		\
+	ori	r3,r3,interrupt_base_book3e@l;	\
+	mtspr	SPRN_IVOR##vector_number,r3;
 
 #endif /* _ASM_POWERPC_EXCEPTION_64E_H */