From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Date: Mon, 20 May 2013 17:23:22 +0000 (+0000)
Subject: powerpc: Fix TLB cleanup at boot on POWER8
X-Git-Tag: v3.10-rc3~17^2~6
X-Git-Url: https://git.kernelconcepts.de/?a=commitdiff_plain;h=8fc1f5d7eff9a4ed0cdb7215e7ca4b82b931d6d7;p=karo-tx-linux.git

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 a283b6442b26..18b5b9cf8e37 100644
--- a/arch/powerpc/kernel/cpu_setup_power.S
+++ b/arch/powerpc/kernel/cpu_setup_power.S
@@ -135,8 +135,12 @@ __init_HFSCR:
 	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