From dcb431e723f132d0df63fb1e711042a6bbfc3a6a Mon Sep 17 00:00:00 2001 From: Alexey Brodkin <abrodkin@synopsys.com> Date: Wed, 24 Dec 2014 17:00:29 +0300 Subject: [PATCH] arc: add dependences on MMU presence Depending on MMU presence in CPU there're differences in HW behavior. For example address of instruction that caused exception is put in ECR register if MMU exists and in ERET register otherwise. Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com> Signed-off-by: Igor Guryanov <guryanov@synopsys.com> --- arch/arc/config.mk | 4 ++++ arch/arc/cpu/arc700/start.S | 18 ++++++++++++++---- 2 files changed, 18 insertions(+), 4 deletions(-) diff --git a/arch/arc/config.mk b/arch/arc/config.mk index e408800a91..5321987a56 100644 --- a/arch/arc/config.mk +++ b/arch/arc/config.mk @@ -21,6 +21,10 @@ ifeq ($(CROSS_COMPILE),) CROSS_COMPILE := $(ARC_CROSS_COMPILE) endif +ifdef CONFIG_ARC_MMU_VER +CONFIG_MMU = 1 +endif + PLATFORM_CPPFLAGS += -ffixed-r25 -D__ARC__ -gdwarf-2 # Needed for relocation diff --git a/arch/arc/cpu/arc700/start.S b/arch/arc/cpu/arc700/start.S index 4d505bfb7c..2318282bf4 100644 --- a/arch/arc/cpu/arc700/start.S +++ b/arch/arc/cpu/arc700/start.S @@ -78,6 +78,16 @@ PUSHAX %erbta .endm +.macro SAVE_EXCEPTION_SOURCE +#ifdef CONFIG_MMU + /* If MMU exists exception faulting address is loaded in EFA reg */ + lr %r0, [%efa] +#else + /* Otherwise in ERET (exception return) reg */ + lr %r0, [%eret] +#endif +.endm + .align 4 .globl _start _start: @@ -102,13 +112,13 @@ _start: memory_error: SAVE_ALL_SYS - lr %r0, [%efa] + SAVE_EXCEPTION_SOURCE mov %r1, %sp j do_memory_error instruction_error: SAVE_ALL_SYS - lr %r0, [%efa] + SAVE_EXCEPTION_SOURCE mov %r1, %sp j do_instruction_error @@ -119,7 +129,7 @@ interrupt_handler: EV_MachineCheck: SAVE_ALL_SYS - lr %r0, [%efa] + SAVE_EXCEPTION_SOURCE mov %r1, %sp j do_machine_check_fault @@ -135,7 +145,7 @@ EV_TLBMissD: EV_TLBProtV: SAVE_ALL_SYS - lr %r0, [%efa] + SAVE_EXCEPTION_SOURCE mov %r1, %sp j do_tlb_prot_violation -- 2.39.5