mpw/cpu/CpuModule_StackFrameGen.c
Kelvin Sherlock 5976f91a89 synchronize with fellow cpu update.
- edge-case fixes for bcd ops
- tweak division by 0 exception a bit
- clean up includes
2016-05-16 13:45:32 -04:00

258 lines
8.3 KiB
C

/* @(#) $Id: CpuModule_StackFrameGen.c,v 1.3 2011-07-18 17:22:55 peschau Exp $ */
/*=========================================================================*/
/* Fellow */
/* 68000 stack frame generation */
/* */
/* Author: Petter Schau */
/* */
/* Copyright (C) 1991, 1992, 1996 Free Software Foundation, Inc. */
/* */
/* 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, 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. */
/*=========================================================================*/
#include "defs.h"
#include "CpuModule_Memory.h"
#include "CpuModule.h"
#include "CpuModule_Internal.h"
/* Exception stack frame jmptables */
typedef void(*cpuStackFrameGenFunc)(UWO, ULO);
static cpuStackFrameGenFunc cpu_stack_frame_gen_func[64];
static void cpuSetStackFrameGenFunc(ULO vector_no, cpuStackFrameGenFunc func)
{
cpu_stack_frame_gen_func[vector_no] = func;
}
/*========================================================================
Group 1 Frame format
000: All, except bus and address error
========================================================================*/
static void cpuFrameGroup1(UWO vector_offset, ULO pcPtr)
{
// save PC
cpuSetAReg(7, cpuGetAReg(7) - 4);
memoryWriteLong(pcPtr, cpuGetAReg(7));
// save SR
cpuSetAReg(7, cpuGetAReg(7) - 2);
memoryWriteWord((UWO)cpuGetSR(), cpuGetAReg(7));
}
/*========================================================================
Group 2 Frame format
000: Bus and address error
memory_fault_address contains the violating address
memory_fault_read is TRUE if the access was a read
========================================================================*/
static void cpuFrameGroup2(UWO vector_offset, ULO pcPtr)
{
// save PC
cpuSetAReg(7, cpuGetAReg(7) - 4);
memoryWriteLong(pcPtr, cpuGetAReg(7));
// save SR
cpuSetAReg(7, cpuGetAReg(7) - 2);
memoryWriteWord((UWO)cpuGetSR(), cpuGetAReg(7));
// fault address, skip ireg
cpuSetAReg(7, cpuGetAReg(7) - 6);
memoryWriteLong(memory_fault_address, cpuGetAReg(7));
cpuSetAReg(7, cpuGetAReg(7) - 2);
memoryWriteLong(memory_fault_read << 4, cpuGetAReg(7));
}
static void cpuFrame4Words(UWO frame_code, UWO vector_offset, ULO pc)
{
// save vector_offset word
cpuSetAReg(7, cpuGetAReg(7) - 2);
memoryWriteWord(frame_code | vector_offset, cpuGetAReg(7));
// save PC
cpuSetAReg(7, cpuGetAReg(7) - 4);
memoryWriteLong(pc, cpuGetAReg(7));
// save SR
cpuSetAReg(7, cpuGetAReg(7) - 2);
memoryWriteWord((UWO)cpuGetSR(), cpuGetAReg(7));
}
/*========================================================================
Frame format $0, four word frame
Stack words:
------------
SR
PCHI
PCLO
0000 Vector offset (4 upper bits are frame no., rest is vector offset)
010: All, except bus and address errors
020: Irq, Format error, Trap #N, Illegal inst., A-line, F-line,
Priv. violation, copr preinst
030: Same as for 020
========================================================================*/
static void cpuFrame0(UWO vector_offset, ULO pc)
{
cpuFrame4Words(0x0000, vector_offset, pc);
}
/*========================================================================
Frame format $1, 4 word throwaway frame
Stack words:
------------
SR
PCHI
PCLO
0000 Vector offset (4 upper bits are frame no., rest is Vvctor offset)
020: Irq, second frame created
030: Same as for 020
040: Same as for 020
========================================================================*/
void cpuFrame1(UWO vector_offset, ULO pc)
{
cpuFrame4Words(0x1000, vector_offset, pc);
}
/*========================================================================
Frame format $2
020: chk, chk2, cpTrapcc, trapcc, trapv, trace, zero divide, MMU config,
copr postinst
030: Same as for 020
040: chk, chk2, FTrapcc, trapcc, trapv, trace, zero divide, address error,
Unimplemented FPU inst.
060: Same as for 040
========================================================================*/
static void cpuFrame2(UWO vector_offset, ULO pc)
{
// save inst address
cpuSetAReg(7, cpuGetAReg(7) - 4);
memoryWriteLong(cpuGetOriginalPC(), cpuGetAReg(7));
cpuFrame4Words(0x2000, vector_offset, pc);
}
/*========================================================================
Frame format $8
010: Bus and address error
========================================================================*/
static void cpuFrame8(UWO vector_offset, ULO pc)
{
cpuSetAReg(7, cpuGetAReg(7) - 50);
cpuFrame4Words(0x8000, vector_offset, pc);
}
/*========================================================================
Frame format $A
020: Address or bus-error on instruction boundrary
030: Same as for 020
Will not set any values beyond the format/offset word
Fellow will always generate this frame for bus/address errors
========================================================================*/
static void cpuFrameA(UWO vector_offset, ULO pc)
{
// save vector_offset offset
cpuSetAReg(7, cpuGetAReg(7) - 24);
cpuFrame4Words(0xa000, vector_offset, pc);
}
void cpuStackFrameGenerate(UWO vector_offset, ULO pc)
{
cpu_stack_frame_gen_func[vector_offset>>2](vector_offset, pc);
}
/*==================================*/
/* Initialize stack frame jmptables */
/*==================================*/
static void cpuStackFrameInitSetDefaultFunc(cpuStackFrameGenFunc default_func)
{
ULO i;
for (i = 0; i < 64; i++)
cpuSetStackFrameGenFunc(i, default_func);
}
static void cpuStackFrameInit000(void)
{
cpuStackFrameInitSetDefaultFunc(cpuFrameGroup1);
cpuSetStackFrameGenFunc(2, cpuFrameGroup2); /* 2 - Bus error */
cpuSetStackFrameGenFunc(3, cpuFrameGroup2); /* 3 - Address error */
}
static void cpuStackFrameInit010(void)
{
cpuStackFrameInitSetDefaultFunc(cpuFrame0);
cpuSetStackFrameGenFunc(2, cpuFrame8); /* 2 - Bus error */
cpuSetStackFrameGenFunc(3, cpuFrame8); /* 3 - Address error */
}
static void cpuStackFrameInit020(void)
{
cpuStackFrameInitSetDefaultFunc(cpuFrame0);
cpuSetStackFrameGenFunc(2, cpuFrameA); /* 2 - Bus Error */
cpuSetStackFrameGenFunc(3, cpuFrameA); /* 3 - Addrss Error */
cpuSetStackFrameGenFunc(5, cpuFrame2); /* 5 - Zero Divide */
cpuSetStackFrameGenFunc(6, cpuFrame2); /* 6 - CHK, CHK2 */
cpuSetStackFrameGenFunc(7, cpuFrame2); /* 7 - TRAPV, TRAPcc, cpTRAPcc */
cpuSetStackFrameGenFunc(9, cpuFrame2); /* 9 - Trace */
}
static void cpuStackFrameInit030(void)
{
cpuStackFrameInitSetDefaultFunc(cpuFrame0);
cpuSetStackFrameGenFunc(2, cpuFrameA); /* 2 - Bus Error */
cpuSetStackFrameGenFunc(3, cpuFrameA); /* 3 - Addrss Error */
cpuSetStackFrameGenFunc(5, cpuFrame2); /* 5 - Zero Divide */
cpuSetStackFrameGenFunc(6, cpuFrame2); /* 6 - CHK, CHK2 */
cpuSetStackFrameGenFunc(7, cpuFrame2); /* 7 - TRAPV, TRAPcc, cpTRAPcc */
cpuSetStackFrameGenFunc(9, cpuFrame2); /* 9 - Trace */
}
void cpuStackFrameInit(void)
{
switch (cpuGetModelMajor())
{
case 0:
cpuStackFrameInit000();
break;
case 1:
cpuStackFrameInit010();
break;
case 2:
cpuStackFrameInit020();
break;
case 3:
cpuStackFrameInit030();
break;
}
}