From cc562d2eae93bc2768a6575d31c089719e8939e8 Mon Sep 17 00:00:00 2001 From: Vineet Gupta Date: Fri, 18 Jan 2013 15:12:19 +0530 Subject: ARC: MMU Exception Handling * MMU I-TLB / D-TLB Miss Exceptions - Fast Path TLB Refill Handler - slowpath TLB creation via do_page_fault() -> update_mmu_cache() * Duplicate PD Exception Handler Signed-off-by: Vineet Gupta --- arch/arc/include/asm/tlb-mmu1.h | 104 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 104 insertions(+) create mode 100644 arch/arc/include/asm/tlb-mmu1.h (limited to 'arch/arc/include/asm/tlb-mmu1.h') diff --git a/arch/arc/include/asm/tlb-mmu1.h b/arch/arc/include/asm/tlb-mmu1.h new file mode 100644 index 000000000000..a5ff961b1efc --- /dev/null +++ b/arch/arc/include/asm/tlb-mmu1.h @@ -0,0 +1,104 @@ +/* + * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#ifndef __ASM_TLB_MMU_V1_H__ +#define __ASM_TLB_MMU_V1_H__ + +#if defined(__ASSEMBLY__) && defined(CONFIG_ARC_MMU_VER == 1) + +#include + +.macro TLB_WRITE_HEURISTICS + +#define JH_HACK1 +#undef JH_HACK2 +#undef JH_HACK3 + +#ifdef JH_HACK3 +; Calculate set index for 2-way MMU +; -avoiding use of GetIndex from MMU +; and its unpleasant LFSR pseudo-random sequence +; +; r1 = TLBPD0 from TLB_RELOAD above +; +; -- jh_ex_way_set not cleared on startup +; didn't want to change setup.c +; hence extra instruction to clean +; +; -- should be in cache since in same line +; as r0/r1 saves above +; +ld r0,[jh_ex_way_sel] ; victim pointer +and r0,r0,1 ; clean +xor.f r0,r0,1 ; flip +st r0,[jh_ex_way_sel] ; store back +asr r0,r1,12 ; get set # <<1, note bit 12=R=0 +or.nz r0,r0,1 ; set way bit +and r0,r0,0xff ; clean +sr r0,[ARC_REG_TLBINDEX] +#endif + +#ifdef JH_HACK2 +; JH hack #2 +; Faster than hack #1 in non-thrash case, but hard-coded for 2-way MMU +; Slower in thrash case (where it matters) because more code is executed +; Inefficient due to two-register paradigm of this miss handler +; +/* r1 = data TLBPD0 at this point */ +lr r0,[eret] /* instruction address */ +xor r0,r0,r1 /* compare set # */ +and.f r0,r0,0x000fe000 /* 2-way MMU mask */ +bne 88f /* not in same set - no need to probe */ + +lr r0,[eret] /* instruction address */ +and r0,r0,PAGE_MASK /* VPN of instruction address */ +; lr r1,[ARC_REG_TLBPD0] /* Data VPN+ASID - already in r1 from TLB_RELOAD*/ +and r1,r1,0xff /* Data ASID */ +or r0,r0,r1 /* Instruction address + Data ASID */ + +lr r1,[ARC_REG_TLBPD0] /* save TLBPD0 containing data TLB*/ +sr r0,[ARC_REG_TLBPD0] /* write instruction address to TLBPD0 */ +sr TLBProbe, [ARC_REG_TLBCOMMAND] /* Look for instruction */ +lr r0,[ARC_REG_TLBINDEX] /* r0 = index where instruction is, if at all */ +sr r1,[ARC_REG_TLBPD0] /* restore TLBPD0 */ + +xor r0,r0,1 /* flip bottom bit of data index */ +b.d 89f +sr r0,[ARC_REG_TLBINDEX] /* and put it back */ +88: +sr TLBGetIndex, [ARC_REG_TLBCOMMAND] +89: +#endif + +#ifdef JH_HACK1 +; +; Always checks whether instruction will be kicked out by dtlb miss +; +mov_s r3, r1 ; save PD0 prepared by TLB_RELOAD in r3 +lr r0,[eret] /* instruction address */ +and r0,r0,PAGE_MASK /* VPN of instruction address */ +bmsk r1,r3,7 /* Data ASID, bits 7-0 */ +or_s r0,r0,r1 /* Instruction address + Data ASID */ + +sr r0,[ARC_REG_TLBPD0] /* write instruction address to TLBPD0 */ +sr TLBProbe, [ARC_REG_TLBCOMMAND] /* Look for instruction */ +lr r0,[ARC_REG_TLBINDEX] /* r0 = index where instruction is, if at all */ +sr r3,[ARC_REG_TLBPD0] /* restore TLBPD0 */ + +sr TLBGetIndex, [ARC_REG_TLBCOMMAND] +lr r1,[ARC_REG_TLBINDEX] /* r1 = index where MMU wants to put data */ +cmp r0,r1 /* if no match on indices, go around */ +xor.eq r1,r1,1 /* flip bottom bit of data index */ +sr r1,[ARC_REG_TLBINDEX] /* and put it back */ +#endif + +.endm + +#endif + +#endif -- cgit