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Diffstat (limited to 'sim/arm/armvirt.c')
| -rw-r--r-- | sim/arm/armvirt.c | 491 |
1 files changed, 491 insertions, 0 deletions
diff --git a/sim/arm/armvirt.c b/sim/arm/armvirt.c new file mode 100644 index 0000000..57ebedf --- /dev/null +++ b/sim/arm/armvirt.c @@ -0,0 +1,491 @@ +/* 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 + +#define ABORTS + +#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 + +/***************************************************************************\ +* Get a Word from Virtual Memory, maybe allocating the page * +\***************************************************************************/ + +static ARMword +GetWord (ARMul_State * state, ARMword address) +{ + ARMword page; + ARMword 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; + ARMword 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; +} + +/***************************************************************************\ +* 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; + + 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; +} + +/***************************************************************************\ +* ReLoad Instruction * +\***************************************************************************/ + +ARMword +ARMul_ReLoadInstr (ARMul_State * state, ARMword address, ARMword isize) +{ +#ifdef ABORTS + if (address >= LOWABORT && address < HIGHABORT) + { + ARMul_PREFETCHABORT (address); + return ARMul_ABORTWORD; + } + else + { + ARMul_CLEARABORT; + } +#endif + + if ((isize == 2) && (address & 0x2)) + { + /* We return the next two halfwords: */ + ARMword lo = GetWord (state, address); + ARMword hi = GetWord (state, address + 4); + + if (state->bigendSig == HIGH) + return (lo << 16) | (hi >> 16); + else + return ((hi & 0xFFFF) << 16) | (lo >> 16); + } + + return GetWord (state, address); +} + +/***************************************************************************\ +* Load Instruction, Sequential Cycle * +\***************************************************************************/ + +ARMword +ARMul_LoadInstrS (ARMul_State * state, ARMword address, ARMword isize) +{ + state->NumScycles ++; + +#ifdef HOURGLASS + if (( state->NumScycles & HOURGLASS_RATE ) == 0) + { + HOURGLASS; + } +#endif + + return ARMul_ReLoadInstr (state, address, isize); +} + +/***************************************************************************\ +* Load Instruction, Non Sequential Cycle * +\***************************************************************************/ + +ARMword +ARMul_LoadInstrN (ARMul_State * state, ARMword address, ARMword isize) +{ + state->NumNcycles ++; + + return ARMul_ReLoadInstr (state, address, isize); +} + +/***************************************************************************\ +* 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); +} + +/***************************************************************************\ +* Load Word, Sequential Cycle * +\***************************************************************************/ + +ARMword +ARMul_LoadWordS (ARMul_State * state, ARMword address) +{ + state->NumScycles ++; + + return ARMul_ReadWord (state, address); +} + +/***************************************************************************\ +* Load Word, Non Sequential Cycle * +\***************************************************************************/ + +ARMword +ARMul_LoadWordN (ARMul_State * state, ARMword address) +{ + state->NumNcycles ++; + + return ARMul_ReadWord (state, address); +} + +/***************************************************************************\ +* Load Halfword, (Non Sequential Cycle) * +\***************************************************************************/ + +ARMword +ARMul_LoadHalfWord (ARMul_State * state, ARMword address) +{ + ARMword temp, offset; + + state->NumNcycles ++; + + temp = ARMul_ReadWord (state, address); + offset = (((ARMword)state->bigendSig * 2) ^ (address & 2)) << 3; /* bit offset into the word */ + + return (temp >> offset) & 0xffff; +} + +/***************************************************************************\ +* Read Byte (but don't tell anyone!) * +\***************************************************************************/ + +ARMword +ARMul_ReadByte (ARMul_State * state, ARMword address) +{ + ARMword temp, offset; + + temp = ARMul_ReadWord (state, address); + offset = (((ARMword)state->bigendSig * 3) ^ (address & 3)) << 3; /* bit offset into the word */ + + return (temp >> offset & 0xffL); +} + +/***************************************************************************\ +* Load Byte, (Non Sequential Cycle) * +\***************************************************************************/ + +ARMword +ARMul_LoadByte (ARMul_State * state, ARMword address) +{ + state->NumNcycles ++; + + return ARMul_ReadByte (state, address); +} + +/***************************************************************************\ +* 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); +} + +/***************************************************************************\ +* Store Word, Sequential Cycle * +\***************************************************************************/ + +void +ARMul_StoreWordS (ARMul_State * state, ARMword address, ARMword data) +{ + state->NumScycles ++; + + ARMul_WriteWord (state, address, data); +} + +/***************************************************************************\ +* Store Word, Non Sequential Cycle * +\***************************************************************************/ + +void +ARMul_StoreWordN (ARMul_State * state, ARMword address, ARMword data) +{ + state->NumNcycles ++; + + ARMul_WriteWord (state, address, data); +} + +/***************************************************************************\ +* Store HalfWord, (Non Sequential Cycle) * +\***************************************************************************/ + +void +ARMul_StoreHalfWord (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 + + temp = ARMul_ReadWord (state, address); + offset = (((ARMword)state->bigendSig * 2) ^ (address & 2)) << 3; /* bit offset into the word */ + + PutWord (state, address, (temp & ~(0xffffL << offset)) | ((data & 0xffffL) << offset)); +} + +/***************************************************************************\ +* Write Byte (but don't tell anyone!) * +\***************************************************************************/ + +void +ARMul_WriteByte (ARMul_State * state, ARMword address, ARMword data) +{ + ARMword temp, offset; + + temp = ARMul_ReadWord (state, address); + offset = (((ARMword)state->bigendSig * 3) ^ (address & 3)) << 3; /* bit offset into the word */ + + PutWord (state, address, (temp & ~(0xffL << offset)) | ((data & 0xffL) << offset)); +} + +/***************************************************************************\ +* Store Byte, (Non Sequential Cycle) * +\***************************************************************************/ + +void +ARMul_StoreByte (ARMul_State * state, ARMword address, ARMword data) +{ + state->NumNcycles ++; + +#ifdef VALIDATE + if (address == TUBE) + { + if (data == 4) + state->Emulate = FALSE; + else + (void) putc ((char)data,stderr); /* Write Char */ + return; + } +#endif + + ARMul_WriteByte (state, address, data); +} + +/***************************************************************************\ +* Swap Word, (Two Non Sequential Cycles) * +\***************************************************************************/ + +ARMword +ARMul_SwapWord (ARMul_State * state, ARMword address, ARMword data) +{ + ARMword temp; + + state->NumNcycles ++; + + temp = ARMul_ReadWord (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; + + 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; +} + + + |