| 1 |
cebix |
1.1 |
/* |
| 2 |
cebix |
1.4 |
* asm_support.s - Utility functions in assembly language (for native 68k support) |
| 3 |
cebix |
1.1 |
* |
| 4 |
cebix |
1.6 |
* Basilisk II (C) 1997-2004 Christian Bauer |
| 5 |
cebix |
1.1 |
* |
| 6 |
|
|
* This program is free software; you can redistribute it and/or modify |
| 7 |
|
|
* it under the terms of the GNU General Public License as published by |
| 8 |
|
|
* the Free Software Foundation; either version 2 of the License, or |
| 9 |
|
|
* (at your option) any later version. |
| 10 |
|
|
* |
| 11 |
|
|
* This program is distributed in the hope that it will be useful, |
| 12 |
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 13 |
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 14 |
|
|
* GNU General Public License for more details. |
| 15 |
|
|
* |
| 16 |
|
|
* You should have received a copy of the GNU General Public License |
| 17 |
|
|
* along with this program; if not, write to the Free Software |
| 18 |
|
|
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| 19 |
|
|
*/ |
| 20 |
|
|
|
| 21 |
|
|
.file "asm_support.s" |
| 22 |
|
|
.text |
| 23 |
|
|
|
| 24 |
|
|
.globl _m68k_sync_icache |
| 25 |
|
|
.globl _Start680x0__Fv |
| 26 |
|
|
.globl _SetInterruptFlag__FUi |
| 27 |
|
|
.globl _ClearInterruptFlag__FUi |
| 28 |
|
|
.globl _Execute68k |
| 29 |
|
|
.globl _Execute68kTrap |
| 30 |
|
|
.globl _EmulOpTrampoline |
| 31 |
|
|
|
| 32 |
|
|
.globl _RAMBaseHost |
| 33 |
|
|
.globl _ROMBaseHost |
| 34 |
|
|
.globl _EmulOp__FUsP13M68kRegisters |
| 35 |
|
|
.globl _EmulatedSR |
| 36 |
|
|
.globl _InterruptFlags |
| 37 |
|
|
.globl _TriggerInterrupt__Fv |
| 38 |
|
|
|
| 39 |
|
|
|
| 40 |
|
|
/* |
| 41 |
|
|
* Call m68k_sync_icache() (NetBSD, the version in libm68k is broken) |
| 42 |
|
|
*/ |
| 43 |
|
|
|
| 44 |
|
|
.type _m68k_sync_icache,@function |
| 45 |
|
|
_m68k_sync_icache: |
| 46 |
|
|
movl sp@(8),d1 |
| 47 |
|
|
movl sp@(4),a1 |
| 48 |
|
|
movl #0x80000004,d0 |
| 49 |
|
|
trap #12 |
| 50 |
|
|
rts |
| 51 |
|
|
|
| 52 |
|
|
|
| 53 |
|
|
/* |
| 54 |
|
|
* Jump to Mac ROM, start emulation |
| 55 |
|
|
*/ |
| 56 |
|
|
|
| 57 |
|
|
.type _Start680x0__Fv,@function |
| 58 |
|
|
_Start680x0__Fv: |
| 59 |
|
|
movl _RAMBaseHost,a0 |
| 60 |
|
|
addl #0x8000,a0 |
| 61 |
|
|
movl a0,sp |
| 62 |
|
|
movl _ROMBaseHost,a0 |
| 63 |
|
|
lea a0@(0x2a),a0 |
| 64 |
|
|
jmp a0@ |
| 65 |
|
|
|
| 66 |
|
|
|
| 67 |
|
|
/* |
| 68 |
|
|
* Set/clear interrupt flag (atomically) |
| 69 |
|
|
*/ |
| 70 |
|
|
|
| 71 |
|
|
.type _SetInterruptFlag__FUi,@function |
| 72 |
|
|
_SetInterruptFlag__FUi: |
| 73 |
|
|
movl sp@(4),d0 |
| 74 |
|
|
orl d0,_InterruptFlags |
| 75 |
|
|
rts |
| 76 |
|
|
|
| 77 |
|
|
.type _ClearInterruptFlag__FUi,@function |
| 78 |
|
|
_ClearInterruptFlag__FUi: |
| 79 |
|
|
movl sp@(4),d0 |
| 80 |
|
|
notl d0 |
| 81 |
|
|
andl d0,_InterruptFlags |
| 82 |
|
|
rts |
| 83 |
|
|
|
| 84 |
|
|
|
| 85 |
|
|
/* |
| 86 |
|
|
* Execute 68k subroutine (must be ended with rts) |
| 87 |
|
|
* r->a[7] and r->sr are unused! |
| 88 |
|
|
*/ |
| 89 |
|
|
|
| 90 |
|
|
/* void Execute68k(uint32 addr, M68kRegisters *r); */ |
| 91 |
|
|
.type _Execute68k,@function |
| 92 |
|
|
_Execute68k: movl sp@(4),d0 |Get arguments |
| 93 |
|
|
movl sp@(8),a0 |
| 94 |
|
|
|
| 95 |
|
|
movml d2-d7/a2-a6,sp@- |Save registers |
| 96 |
|
|
|
| 97 |
|
|
movl a0,sp@- |Push pointer to M68kRegisters on stack |
| 98 |
|
|
pea exec68kret |Push return address on stack |
| 99 |
|
|
movl d0,sp@- |Push pointer to 68k routine on stack |
| 100 |
|
|
movml a0@,d0-d7/a0-a6 |Load registers from M68kRegisters |
| 101 |
|
|
|
| 102 |
|
|
rts |Jump into 68k routine |
| 103 |
|
|
|
| 104 |
|
|
exec68kret: movl a6,sp@- |Save a6 |
| 105 |
|
|
movl sp@(4),a6 |Get pointer to M68kRegisters |
| 106 |
|
|
movml d0-d7/a0-a5,a6@ |Save d0-d7/a0-a5 to M68kRegisters |
| 107 |
|
|
movl sp@+,a6@(56) |Save a6 to M68kRegisters |
| 108 |
|
|
addql #4,sp |Remove pointer from stack |
| 109 |
|
|
|
| 110 |
|
|
movml sp@+,d2-d7/a2-a6 |Restore registers |
| 111 |
|
|
rts |
| 112 |
|
|
|
| 113 |
|
|
|
| 114 |
|
|
/* |
| 115 |
|
|
* Execute MacOS 68k trap |
| 116 |
|
|
* r->a[7] and r->sr are unused! |
| 117 |
|
|
*/ |
| 118 |
|
|
|
| 119 |
|
|
/* void Execute68kTrap(uint16 trap, M68kRegisters *r); */ |
| 120 |
|
|
.type _Execute68kTrap,@function |
| 121 |
|
|
_Execute68kTrap: |
| 122 |
|
|
movl sp@(4),d0 |Get arguments |
| 123 |
|
|
movl sp@(8),a0 |
| 124 |
|
|
|
| 125 |
|
|
movml d2-d7/a2-a6,sp@- |Save registers |
| 126 |
|
|
|
| 127 |
|
|
movl a0,sp@- |Push pointer to M68kRegisters on stack |
| 128 |
|
|
movw d0,sp@- |Push trap word on stack |
| 129 |
|
|
subql #8,sp |Create fake A-Line exception frame |
| 130 |
|
|
movml a0@,d0-d7/a0-a6 |Load registers from M68kRegisters |
| 131 |
|
|
|
| 132 |
|
|
movl a2,sp@- |Save a2 and d2 |
| 133 |
|
|
movl d2,sp@- |
| 134 |
|
|
lea exectrapret,a2 |a2 points to return address |
| 135 |
|
|
movw sp@(16),d2 |Load trap word into d2 |
| 136 |
|
|
|
| 137 |
|
|
jmp zpc@(0x28:w)@(10) |Jump into MacOS A-Line handler |
| 138 |
|
|
|
| 139 |
|
|
exectrapret: movl a6,sp@- |Save a6 |
| 140 |
|
|
movl sp@(6),a6 |Get pointer to M68kRegisters |
| 141 |
|
|
movml d0-d7/a0-a5,a6@ |Save d0-d7/a0-a5 to M68kRegisters |
| 142 |
|
|
movl sp@+,a6@(56) |Save a6 to M68kRegisters |
| 143 |
|
|
addql #6,sp |Remove pointer and trap word from stack |
| 144 |
|
|
|
| 145 |
|
|
movml sp@+,d2-d7/a2-a6 |Restore registers |
| 146 |
|
|
rts |
| 147 |
|
|
|
| 148 |
|
|
|
| 149 |
|
|
/* |
| 150 |
|
|
* Call EmulOp() after return from SIGILL handler, registers are pushed on stack |
| 151 |
|
|
*/ |
| 152 |
|
|
|
| 153 |
|
|
.type _EmulOpTrampoline,@function |
| 154 |
|
|
_EmulOpTrampoline: |
| 155 |
|
|
movl sp,a0 |Get pointer to registers |
| 156 |
|
|
|
| 157 |
|
|
movw _EmulatedSR,d0 |Save EmulatedSR, disable interrupts |
| 158 |
|
|
movw d0,sp@- |
| 159 |
|
|
oriw #0x0700,d0 |
| 160 |
|
|
movw d0,_EmulatedSR |
| 161 |
|
|
|
| 162 |
|
|
movl a0,sp@- |Push pointer to registers |
| 163 |
|
|
movl a0@(66),a1 |Get saved PC |
| 164 |
|
|
addql #2,a0@(66) |Skip EMUL_OP opcode |
| 165 |
|
|
movw a1@,sp@- |Push opcode word |
| 166 |
|
|
clrw sp@- |
| 167 |
|
|
jbsr _EmulOp__FUsP13M68kRegisters |
| 168 |
|
|
addql #8,sp |
| 169 |
|
|
|
| 170 |
|
|
movw sp@+,d0 |Restore interrupts, trigger pending interrupt |
| 171 |
|
|
movw d0,_EmulatedSR |
| 172 |
|
|
andiw #0x0700,d0 |
| 173 |
|
|
bne eot1 |
| 174 |
|
|
tstl _InterruptFlags |
| 175 |
|
|
beq eot1 |
| 176 |
|
|
jbsr _TriggerInterrupt__Fv |
| 177 |
|
|
|
| 178 |
|
|
eot1: moveml sp@+,d0-d7/a0-a6 |Restore registers |
| 179 |
|
|
addql #4,sp |Skip saved SP |
| 180 |
|
|
rtr |
