From 30b7af252e8fef6bf2fc311ca654c40bd0552220 Mon Sep 17 00:00:00 2001 From: Noam Camus Date: Sun, 28 May 2017 09:52:03 +0300 Subject: [PATCH] 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 Signed-off-by: Vineet Gupta --- arch/arc/mm/tlbex.S | 9 +++++++++ 1 file changed, 9 insertions(+) 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