From: Noam Camus <noamca@mellanox.com>
Date: Sun, 28 May 2017 06:52:03 +0000 (+0300)
Subject: ARC: [plat-eznps] Fix TLB Errata
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=30b7af252e8fef6bf2fc311ca654c40bd0552220;p=GitHub%2FLineageOS%2Fandroid_kernel_motorola_exynos9610.git

ARC: [plat-eznps] Fix TLB Errata

Due to a HW bug in NPS400 we get from time to time false TLB miss.
Workaround this by validating each miss.

Signed-off-by: Noam Camus <noamca@mellanox.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
---

diff --git a/arch/arc/mm/tlbex.S b/arch/arc/mm/tlbex.S
index b30e4e36bb00..0e1e47a67c73 100644
--- a/arch/arc/mm/tlbex.S
+++ b/arch/arc/mm/tlbex.S
@@ -274,6 +274,13 @@ ex_saved_reg1:
 .macro COMMIT_ENTRY_TO_MMU
 #if (CONFIG_ARC_MMU_VER < 4)
 
+#ifdef CONFIG_EZNPS_MTM_EXT
+	/* verify if entry for this vaddr+ASID already exists */
+	sr    TLBProbe, [ARC_REG_TLBCOMMAND]
+	lr    r0, [ARC_REG_TLBINDEX]
+	bbit0 r0, 31, 88f
+#endif
+
 	/* Get free TLB slot: Set = computed from vaddr, way = random */
 	sr  TLBGetIndex, [ARC_REG_TLBCOMMAND]
 
@@ -287,6 +294,8 @@ ex_saved_reg1:
 #else
 	sr TLBInsertEntry, [ARC_REG_TLBCOMMAND]
 #endif
+
+88:
 .endm