powerpc: Fix TLB cleanup at boot on POWER8
The TLB has 512 congruence classes (2048 entries 4 way set associative)
while P7 had 128
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
diff --git a/arch/powerpc/kernel/cpu_setup_power.S b/arch/powerpc/kernel/cpu_setup_power.S
index a283b64..18b5b9c 100644
--- a/arch/powerpc/kernel/cpu_setup_power.S
+++ b/arch/powerpc/kernel/cpu_setup_power.S
@@ -135,8 +135,12 @@
blr
__init_TLB:
- /* Clear the TLB */
- li r6,128
+ /*
+ * Clear the TLB using the "IS 3" form of tlbiel instruction
+ * (invalidate by congruence class). P7 has 128 CCs, P8 has 512
+ * so we just always do 512
+ */
+ li r6,512
mtctr r6
li r7,0xc00 /* IS field = 0b11 */
ptesync