/*
* 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__

#include <asm/mmu.h>

#if defined(__ASSEMBLY__) && (CONFIG_ARC_MMU_VER == 1)

.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