1# Copyright (c) 2013-2014 Jeffrey Pfau
  2#
  3# This Source Code Form is subject to the terms of the Mozilla Public
  4# License, v. 2.0. If a copy of the MPL was not distributed with this
  5# file, You can obtain one at http://mozilla.org/MPL/2.0/.
  6#define nop andeq r0, r0
  7
  8.text
  9
 10b resetBase
 11b undefBase
 12b swiBase
 13b pabtBase
 14b dabtBase
 15nop
 16b irqBase
 17b fiqBase
 18
 19resetBase:
 20mov r0, #0x8000000
 21ldrb r1, [r0, #3]
 22cmp r1, #0xEA
 23ldrne r0, =0x20000C0
 24bx r0
 25.word 0
 26.word 0xE129F000
 27
 28swiBase:
 29cmp    sp, #0
 30moveq  sp, #0x04000000
 31subeq  sp, #0x20
 32stmfd  sp!, {r11-r12, lr}
 33ldrb   r11, [lr, #-2]
 34mov    r12, #swiTable
 35ldr    r11, [r12, r11, lsl #2]
 36cmp    r11, #0
 37mrs    r12, spsr
 38stmfd  sp!, {r12}
 39and    r12, #0x80
 40orr    r12, #0x1F
 41msr    cpsr, r12
 42stmfd  sp!, {lr}
 43nop
 44nop
 45nop
 46nop
 47nop
 48nop
 49nop
 50nop
 51nop
 52nop
 53mov    lr, pc
 54bxne   r11
 55nop
 56nop
 57nop
 58nop
 59ldmfd  sp!, {lr}
 60msr    cpsr, #0x93
 61ldmfd  sp!, {r12}
 62msr    spsr, r12
 63ldmfd  sp!, {r11-r12, lr}
 64movs   pc, lr
 65.word 0
 66.word 0xE3A02004
 67
 68swiTable:
 69.word SoftReset               @ 0x00
 70.word RegisterRamReset        @ 0x01
 71.word Halt                    @ 0x02
 72.word Stop                    @ 0x03
 73.word IntrWait                @ 0x04
 74.word VBlankIntrWait          @ 0x05
 75.word Div                     @ 0x06
 76.word DivArm                  @ 0x07
 77.word Sqrt                    @ 0x08
 78.word ArcTan                  @ 0x09
 79.word ArcTan2                 @ 0x0A
 80.word CpuSet                  @ 0x0B
 81.word CpuFastSet              @ 0x0C
 82.word GetBiosChecksum         @ 0x0D
 83.word BgAffineSet             @ 0x0E
 84.word ObjAffineSet            @ 0x0F
 85.word BitUnPack               @ 0x10
 86.word Lz77UnCompWram          @ 0x11
 87.word Lz77UnCompVram          @ 0x12
 88.word HuffmanUnComp           @ 0x13
 89.word RlUnCompWram            @ 0x14
 90.word RlUnCompVram            @ 0x15
 91.word Diff8BitUnFilterWram    @ 0x16
 92.word Diff8BitUnFilterVram    @ 0x17
 93.word Diff16BitUnFilter       @ 0x18
 94.word SoundBias               @ 0x19
 95.word SoundDriverInit         @ 0x1A
 96.word SoundDriverMode         @ 0x1B
 97.word SoundDriverMain         @ 0x1C
 98.word SoundDriverVsync        @ 0x1D
 99.word SoundChannelClear       @ 0x1E
100.word MidiKey2Freq            @ 0x1F
101.word MusicPlayerOpen         @ 0x20
102.word MusicPlayerStart        @ 0x21
103.word MusicPlayerStop         @ 0x22
104.word MusicPlayerContinue     @ 0x23
105.word MusicPlayerFadeOut      @ 0x24
106.word MultiBoot               @ 0x25
107.word HardReset               @ 0x26
108.word CustomHalt              @ 0x27
109.word SoundDriverVsyncOff     @ 0x28
110.word SoundDriverVsyncOn      @ 0x29
111.word SoundDriverGetJumpList  @ 0x2A
112
113.ltorg
114
115irqBase:
116stmfd  sp!, {r0-r3, r12, lr}
117mov    r0, #0x04000000
118add    lr, pc, #0
119ldr    pc, [r0, #-4]
120ldmfd  sp!, {r0-r3, r12, lr}
121subs   pc, lr, #4
122.word 0
123.word 0xE55EC002
124
125undefBase:
126subs   pc, lr, #4
127.word 0
128.word 0x03A0E004
129
130@ Unimplemented
131SoftReset:
132RegisterRamReset:
133Stop:
134Div:
135DivArm:
136Sqrt:
137ArcTan:
138ArcTan2:
139GetBiosChecksum:
140BgAffineSet:
141ObjAffineSet:
142BitUnPack:
143Lz77UnCompWram:
144Lz77UnCompVram:
145HuffmanUnComp:
146RlUnCompWram:
147RlUnCompVram:
148Diff8BitUnFilterWram:
149Diff8BitUnFilterVram:
150Diff16BitUnFilter:
151SoundBias:
152SoundDriverInit:
153SoundDriverMode:
154SoundDriverMain:
155SoundDriverVsync:
156SoundChannelClear:
157MidiKey2Freq:
158MusicPlayerOpen:
159MusicPlayerStart:
160MusicPlayerStop:
161MusicPlayerContinue:
162MusicPlayerFadeOut:
163MultiBoot:
164HardReset:
165CustomHalt:
166SoundDriverVsyncOff:
167SoundDriverVsyncOn:
168
169NopCall:
170bx lr
171
172Halt:
173mov    r2, #0
174mov    r12, #0x04000000
175strb   r2, [r12, #0x301]
176bx     lr
177
178VBlankIntrWait:
179mov    r0, #1
180mov    r1, #1
181IntrWait:
182stmfd  sp!, {r2-r3, lr}
183mov    r12, #0x04000000
184@ See if we want to return immediately
185cmp    r0, #0
186mov    r0, #0
187mov    r2, #1
188beq    1f
189ldrh   r3, [r12, #-8]
190bic    r3, r1
191strh   r3, [r12, #-8]
192@ Halt
1930:
194strb   r0, [r12, #0x301]
1951:
196@ Check which interrupts were acknowledged
197strb   r0, [r12, #0x208]
198ldrh   r3, [r12, #-8]
199ands   r3, r1
200eorne  r3, r1
201strneh r3, [r12, #-8]
202strb   r2, [r12, #0x208]
203beq    0b
204ldmfd  sp!, {r2-r3, pc}
205
206CpuSet:
207stmfd  sp!, {r4, r5, lr}
208mov    r4, r2, lsl #12
209mov    r12, r0
210mov    r5, r1
211tst    r2, #0x01000000
212beq    0f
213@ Fill
214tst    r2, #0x04000000
215beq    1f
216@ Word
217add    r4, r5, r4, lsr #10
218ldmia  r12!, {r3}
2192:
220cmp    r5, r4
221stmltia  r5!, {r3}
222blt    2b
223b      3f
224@ Halfword
2251:
226bic    r12, #1
227bic    r5, #1
228add    r4, r5, r4, lsr #11
229ldrh   r3, [r12]
2302:
231cmp    r5, r4
232strlth r3, [r5], #2
233blt    2b
234b      3f
235@ Copy
2360:
237tst    r2, #0x04000000
238beq    1f
239@ Word
240add    r4, r5, r4, lsr #10
2412:
242cmp    r5, r4
243ldmltia r12!, {r3}
244stmltia r5!, {r3}
245blt    2b
246b      3f
247@ Halfword
2481:
249add    r4, r5, r4, lsr #11
2502:
251cmp    r5, r4
252ldrlth r3, [r12], #2
253strlth r3, [r5], #2
254blt    2b
2553:
256mov    r3, #0x170  @ Match official BIOS's clobbered r3
257ldmfd  sp!, {r4, r5, pc}
258
259CpuFastSet:
260stmfd  sp!, {r4-r10, lr}
261tst    r2, #0x01000000
262mov    r3, r2, lsl #12
263add    r2, r1, r3, lsr #10
264beq    0f
265@ Fill
266ldr    r3, [r0]
267mov    r4, r3
268mov    r5, r3
269mov    r6, r3
270mov    r7, r3
271mov    r8, r3
272mov    r9, r3
273mov    r10, r3
2741:
275cmp    r1, r2
276stmltia r1!, {r3-r10}
277blt    1b
278b      2f
279@ Copy
2800:
281cmp    r1, r2
282ldmltia r0!, {r3-r10}
283stmltia r1!, {r3-r10}
284blt    0b
2852:
286ldmfd  sp!, {r4-r10, pc}
287
288SoundDriverGetJumpList:
289stmfd  sp!, {r4-r10}
290ldr    r1, =NopCall
291mov    r3, r1
292mov    r4, r1
293mov    r5, r1
294mov    r6, r1
295mov    r7, r1
296mov    r8, r1
297mov    r9, r1
298mov    r10, r1
299stmia  r0!, {r1, r3-r10}
300stmia  r0!, {r1, r3-r10}
301stmia  r0!, {r1, r3-r10}
302stmia  r0!, {r1, r3-r10}
303mov    r1, #0
304ldmfd  sp!, {r4-r10}
305bx     lr
306
307.ltorg