NetBSD/gnu/dist/sim/arm/armvirt.c
1998-02-01 07:56:37 +00:00

478 lines
14 KiB
C

/* armvirt.c -- ARMulator virtual memory interace: ARM6 Instruction Emulator.
Copyright (C) 1994 Advanced RISC Machines Ltd.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
/* This file contains a complete ARMulator memory model, modelling a
"virtual memory" system. A much simpler model can be found in armfast.c,
and that model goes faster too, but has a fixed amount of memory. This
model's memory has 64K pages, allocated on demand from a 64K entry page
table. The routines PutWord and GetWord implement this. Pages are never
freed as they might be needed again. A single area of memory may be
defined to generate aborts. */
#include "armopts.h"
#include "armdefs.h"
#ifdef VALIDATE /* for running the validate suite */
#define TUBE 48 * 1024 * 1024 /* write a char on the screen */
#define ABORTS 1
#endif
#ifdef ABORTS /* the memory system will abort */
/* For the old test suite Abort between 32 Kbytes and 32 Mbytes
For the new test suite Abort between 8 Mbytes and 26 Mbytes */
/* #define LOWABORT 32 * 1024
#define HIGHABORT 32 * 1024 * 1024 */
#define LOWABORT 8 * 1024 * 1024
#define HIGHABORT 26 * 1024 * 1024
#endif
#define NUMPAGES 64 * 1024
#define PAGESIZE 64 * 1024
#define PAGEBITS 16
#define OFFSETBITS 0xffff
static ARMword GetWord(ARMul_State *state,ARMword address) ;
static void PutWord(ARMul_State *state,ARMword address, ARMword data) ;
/***************************************************************************\
* Initialise the memory interface *
\***************************************************************************/
unsigned ARMul_MemoryInit(ARMul_State *state, unsigned long initmemsize)
{ARMword **pagetable ;
unsigned page ;
if (initmemsize)
state->MemSize = initmemsize ;
pagetable = (ARMword **)malloc(sizeof(ARMword)*NUMPAGES) ;
if (pagetable == NULL)
return(FALSE) ;
for (page = 0 ; page < NUMPAGES ; page++)
*(pagetable + page) = NULL ;
state->MemDataPtr = (unsigned char *)pagetable ;
#ifdef BIGEND
state->bigendSig = HIGH ;
#endif
#ifdef LITTLEEND
state->bigendSig = LOW ;
#endif
ARMul_ConsolePrint (state, ", 4 Gb memory") ;
return(TRUE) ;
}
/***************************************************************************\
* Remove the memory interface *
\***************************************************************************/
void ARMul_MemoryExit(ARMul_State *state)
{ARMword page ;
ARMword **pagetable ;
ARMword *pageptr ;
pagetable = (ARMword **)state->MemDataPtr ;
for (page = 0 ; page < NUMPAGES ; page++) {
pageptr = *(pagetable + page) ;
if (pageptr != NULL)
free((char *)pageptr) ;
}
free((char *)pagetable) ;
return ;
}
/***************************************************************************\
* Load Instruction, Sequential Cycle *
\***************************************************************************/
ARMword ARMul_LoadInstrS(ARMul_State *state,ARMword address)
{state->NumScycles++ ;
#ifdef HOURGLASS
if( ( state->NumScycles & HOURGLASS_RATE ) == 0 ) {
HOURGLASS;
}
#endif
#ifdef ABORTS
if (address >= LOWABORT && address < HIGHABORT) {
ARMul_PREFETCHABORT(address) ;
return(ARMul_ABORTWORD) ;
}
else {
ARMul_CLEARABORT ;
}
#endif
return(GetWord(state,address)) ;
}
/***************************************************************************\
* Load Instruction, Non Sequential Cycle *
\***************************************************************************/
ARMword ARMul_LoadInstrN(ARMul_State *state,ARMword address)
{state->NumNcycles++ ;
#ifdef ABORTS
if (address >= LOWABORT && address < HIGHABORT) {
ARMul_PREFETCHABORT(address) ;
return(ARMul_ABORTWORD) ;
}
else {
ARMul_CLEARABORT ;
}
#endif
return(GetWord(state,address)) ;
}
/***************************************************************************\
* Load Word, Sequential Cycle *
\***************************************************************************/
ARMword ARMul_LoadWordS(ARMul_State *state,ARMword address)
{state->NumScycles++ ;
#ifdef ABORTS
if (address >= LOWABORT && address < HIGHABORT) {
ARMul_DATAABORT(address) ;
return(0) ;
}
else {
ARMul_CLEARABORT ;
}
#endif
return(GetWord(state,address)) ;
}
/***************************************************************************\
* Load Word, Non Sequential Cycle *
\***************************************************************************/
ARMword ARMul_LoadWordN(ARMul_State *state,ARMword address)
{state->NumNcycles++ ;
#ifdef ABORTS
if (address >= LOWABORT && address < HIGHABORT) {
ARMul_DATAABORT(address) ;
return(0) ;
}
else {
ARMul_CLEARABORT ;
}
#endif
return(GetWord(state,address)) ;
}
/***************************************************************************\
* Load Byte, (Non Sequential Cycle) *
\***************************************************************************/
ARMword ARMul_LoadByte(ARMul_State *state,ARMword address)
{ARMword temp, offset ;
state->NumNcycles++ ;
#ifdef ABORTS
if (address >= LOWABORT && address < HIGHABORT) {
ARMul_DATAABORT(address) ;
return(0) ;
}
else {
ARMul_CLEARABORT ;
}
#endif
temp = GetWord(state,address) ;
offset = (((ARMword)state->bigendSig * 3) ^ (address & 3)) << 3 ; /* bit offset into the word */
return(temp >> offset & 0xff) ;
}
/***************************************************************************\
* Store Word, Sequential Cycle *
\***************************************************************************/
void ARMul_StoreWordS(ARMul_State *state,ARMword address, ARMword data)
{state->NumScycles++ ;
#ifdef ABORTS
if (address >= LOWABORT && address < HIGHABORT) {
ARMul_DATAABORT(address) ;
return ;
}
else {
ARMul_CLEARABORT ;
}
#endif
PutWord(state,address,data) ;
}
/***************************************************************************\
* Store Word, Non Sequential Cycle *
\***************************************************************************/
void ARMul_StoreWordN(ARMul_State *state, ARMword address, ARMword data)
{state->NumNcycles++ ;
#ifdef ABORTS
if (address >= LOWABORT && address < HIGHABORT) {
ARMul_DATAABORT(address) ;
return ;
}
else {
ARMul_CLEARABORT ;
}
#endif
PutWord(state,address,data) ;
}
/***************************************************************************\
* Store Byte, (Non Sequential Cycle) *
\***************************************************************************/
void ARMul_StoreByte(ARMul_State *state, ARMword address, ARMword data)
{ARMword temp, offset ;
state->NumNcycles++ ;
#ifdef VALIDATE
if (address == TUBE) {
if (data == 4)
state->Emulate = FALSE ;
else
(void)putc((char)data,stderr) ; /* Write Char */
return ;
}
#endif
#ifdef ABORTS
if (address >= LOWABORT && address < HIGHABORT) {
ARMul_DATAABORT(address) ;
return ;
}
else {
ARMul_CLEARABORT ;
}
#endif
temp = GetWord(state,address) ;
offset = (((ARMword)state->bigendSig * 3) ^ (address & 3)) << 3 ; /* bit offset into the word */
PutWord(state,address,(temp & ~(0xffL << offset)) | ((data & 0xffL) << offset)) ;
}
/***************************************************************************\
* Swap Word, (Two Non Sequential Cycles) *
\***************************************************************************/
ARMword ARMul_SwapWord(ARMul_State *state, ARMword address, ARMword data)
{ARMword temp ;
state->NumNcycles++ ;
#ifdef ABORTS
if (address >= LOWABORT && address < HIGHABORT) {
ARMul_DATAABORT(address) ;
return(ARMul_ABORTWORD) ;
}
else {
ARMul_CLEARABORT ;
}
#endif
temp = GetWord(state,address) ;
state->NumNcycles++ ;
PutWord(state,address,data) ;
return(temp) ;
}
/***************************************************************************\
* Swap Byte, (Two Non Sequential Cycles) *
\***************************************************************************/
ARMword ARMul_SwapByte(ARMul_State *state, ARMword address, ARMword data)
{ARMword temp ;
#ifdef ABORTS
if (address >= LOWABORT && address < HIGHABORT) {
ARMul_DATAABORT(address) ;
return(ARMul_ABORTWORD) ;
}
else {
ARMul_CLEARABORT ;
}
#endif
temp = ARMul_LoadByte(state,address) ;
ARMul_StoreByte(state,address,data) ;
return(temp) ;
}
/***************************************************************************\
* Count I Cycles *
\***************************************************************************/
void ARMul_Icycles(ARMul_State *state, unsigned number, ARMword address)
{state->NumIcycles += number ;
ARMul_CLEARABORT ;
}
/***************************************************************************\
* Count C Cycles *
\***************************************************************************/
void ARMul_Ccycles(ARMul_State *state, unsigned number, ARMword address)
{state->NumCcycles += number ;
ARMul_CLEARABORT ;
}
/***************************************************************************\
* Read Word (but don't tell anyone!) *
\***************************************************************************/
ARMword ARMul_ReadWord(ARMul_State *state, ARMword address)
{
#ifdef ABORTS
if (address >= LOWABORT && address < HIGHABORT) {
ARMul_DATAABORT(address) ;
return(ARMul_ABORTWORD) ;
}
else {
ARMul_CLEARABORT ;
}
#endif
return(GetWord(state,address)) ;
}
/***************************************************************************\
* Read Byte (but don't tell anyone!) *
\***************************************************************************/
ARMword ARMul_ReadByte(ARMul_State *state, ARMword address)
{ARMword temp, offset ;
#ifdef ABORTS
if (address >= LOWABORT && address < HIGHABORT) {
ARMul_DATAABORT(address) ;
return(ARMul_ABORTWORD) ;
}
else {
ARMul_CLEARABORT ;
}
#endif
temp = GetWord(state,address) ;
offset = (((ARMword)state->bigendSig * 3) ^ (address & 3)) << 3 ; /* bit offset into the word */
return(temp >> offset & 0xffL) ;
}
/***************************************************************************\
* Write Word (but don't tell anyone!) *
\***************************************************************************/
void ARMul_WriteWord(ARMul_State *state, ARMword address, ARMword data)
{
#ifdef ABORTS
if (address >= LOWABORT && address < HIGHABORT) {
ARMul_DATAABORT(address) ;
return ;
}
else {
ARMul_CLEARABORT ;
}
#endif
PutWord(state,address,data) ;
}
/***************************************************************************\
* Write Byte (but don't tell anyone!) *
\***************************************************************************/
void ARMul_WriteByte(ARMul_State *state, ARMword address, ARMword data)
{ARMword temp, offset ;
#ifdef ABORTS
if (address >= LOWABORT && address < HIGHABORT) {
ARMul_DATAABORT(address) ;
return ;
}
else {
ARMul_CLEARABORT ;
}
#endif
temp = GetWord(state,address) ;
offset = (((ARMword)state->bigendSig * 3) ^ (address & 3)) << 3 ; /* bit offset into the word */
PutWord(state,address,(temp & ~(0xffL << offset)) | ((data & 0xffL) << offset)) ;
}
/***************************************************************************\
* Get a Word from Virtual Memory, maybe allocating the page *
\***************************************************************************/
static ARMword GetWord(ARMul_State *state, ARMword address)
{ARMword page, offset ;
ARMword **pagetable ;
ARMword *pageptr ;
page = address >> PAGEBITS ;
offset = (address & OFFSETBITS) >> 2 ;
pagetable = (ARMword **)state->MemDataPtr ;
pageptr = *(pagetable + page) ;
if (pageptr == NULL) {
pageptr = (ARMword *)malloc(PAGESIZE) ;
if (pageptr == NULL) {
perror("ARMulator can't allocate VM page") ;
exit(12) ;
}
*(pagetable + page) = pageptr ;
}
return(*(pageptr + offset)) ;
}
/***************************************************************************\
* Put a Word into Virtual Memory, maybe allocating the page *
\***************************************************************************/
static void PutWord(ARMul_State *state, ARMword address, ARMword data)
{ARMword page, offset ;
ARMword **pagetable ;
ARMword *pageptr ;
page = address >> PAGEBITS ;
offset = (address & OFFSETBITS) >> 2 ;
pagetable = (ARMword **)state->MemDataPtr ;
pageptr = *(pagetable + page) ;
if (pageptr == NULL) {
pageptr = (ARMword *)malloc(PAGESIZE) ;
if (pageptr == NULL) {
perror("ARMulator can't allocate VM page") ;
exit(13) ;
}
*(pagetable + page) = pageptr ;
}
*(pageptr + offset) = data ;
}