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giz rc1 release
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1@ vim:filetype=armasm
2
3@ Memory I/O handlers for Sega/Mega CD emulation
4@ (c) Copyright 2007, Grazvydas "notaz" Ignotas
5
6
7
8.equiv PCM_STEP_SHIFT, 11
9.equiv POLL_LIMIT, 16
10
11@ jump tables
12.data
13.align 4
14
15.altmacro
16.macro mk_m68k_jump_table on sz @ operation name, size
17 .long m_m68k_&\on&\sz&_bios @ 0x000000 - 0x01ffff
18 .long m_m68k_&\on&\sz&_prgbank @ 0x020000 - 0x03ffff
19 .long m_&\on&_null, m_&\on&_null @ 0x040000 - 0x07ffff
20 .long m_&\on&_null, m_&\on&_null, m_&\on&_null, m_&\on&_null @ 0x080000 - 0x0fffff
21 .long m_&\on&_null, m_&\on&_null, m_&\on&_null, m_&\on&_null @ 0x100000 - 0x17ffff
22 .long m_&\on&_null, m_&\on&_null, m_&\on&_null, m_&\on&_null @ 0x180000 - 0x1fffff
23 .long m_m68k_&\on&\sz&_wordram0_2M @ 0x200000 - 0x21ffff
24 .long m_m68k_&\on&\sz&_wordram1_2M @ 0x220000 - 0x23ffff
25 .long m_&\on&_null, m_&\on&_null @ 0x240000 - 0x27ffff
26 .long m_&\on&_null, m_&\on&_null, m_&\on&_null, m_&\on&_null @ 0x280000 - 0x2fffff
27 .long m_&\on&_null, m_&\on&_null, m_&\on&_null, m_&\on&_null @ 0x300000
28 .long m_&\on&_null, m_&\on&_null, m_&\on&_null, m_&\on&_null @ - 0x3fffff
29 .long m_m68k_&\on&\sz&_bcram_size @ 0x400000
30 .long m_&\on&_null, m_&\on&_null, m_&\on&_null @ 0x420000
31 .long m_&\on&_null, m_&\on&_null, m_&\on&_null, m_&\on&_null @ - 0x4fffff
32 .long m_&\on&_null, m_&\on&_null, m_&\on&_null, m_&\on&_null @ 0x500000
33 .long m_&\on&_null, m_&\on&_null, m_&\on&_null, m_&\on&_null @ - 0x5fffff
34 .long m_m68k_&\on&\sz&_bcram @ 0x600000
35 .long m_&\on&_null, m_&\on&_null, m_&\on&_null @ 0x620000
36 .long m_&\on&_null, m_&\on&_null, m_&\on&_null, m_&\on&_null @ - 0x6fffff
37 .long m_&\on&_null, m_&\on&_null, m_&\on&_null, m_&\on&_null @ 0x700000
38 .long m_&\on&_null, m_&\on&_null, m_&\on&_null @ - 0x7dffff
39 .long m_m68k_&\on&\sz&_bcram_reg @ 0x7e0000
40 .long m_&\on&_null, m_&\on&_null, m_&\on&_null, m_&\on&_null @ 0x800000
41 .long m_&\on&_null, m_&\on&_null, m_&\on&_null, m_&\on&_null @ - 0x8fffff
42 .long m_&\on&_null, m_&\on&_null, m_&\on&_null, m_&\on&_null @ 0x900000
43 .long m_&\on&_null, m_&\on&_null, m_&\on&_null, m_&\on&_null @ - 0x9fffff
44 .long m_m68k_&\on&\sz&_system_io @ 0xa00000 - 0xa1ffff
45 .long m_&\on&_null, m_&\on&_null, m_&\on&_null @ 0xa20000 - 0xa7ffff
46 .long m_&\on&_null, m_&\on&_null, m_&\on&_null, m_&\on&_null @ 0xa80000 - 0xafffff
47 .long m_&\on&_null, m_&\on&_null, m_&\on&_null, m_&\on&_null @ 0xb00000
48 .long m_&\on&_null, m_&\on&_null, m_&\on&_null, m_&\on&_null @ - 0xbfffff
49 .long m_m68k_&\on&\sz&_vdp, m_m68k_&\on&\sz&_vdp, m_m68k_&\on&\sz&_vdp, m_m68k_&\on&\sz&_vdp @ 0xc00000
50 .long m_m68k_&\on&\sz&_vdp, m_m68k_&\on&\sz&_vdp, m_m68k_&\on&\sz&_vdp, m_m68k_&\on&\sz&_vdp @ - 0xcfffff
51 .long m_&\on&_null, m_&\on&_null, m_&\on&_null, m_&\on&_null @ 0xd00000
52 .long m_&\on&_null, m_&\on&_null, m_&\on&_null, m_&\on&_null @ - 0xdfffff
53 .long m_m68k_&\on&\sz&_ram, m_m68k_&\on&\sz&_ram, m_m68k_&\on&\sz&_ram, m_m68k_&\on&\sz&_ram @ 0xe00000
54 .long m_m68k_&\on&\sz&_ram, m_m68k_&\on&\sz&_ram, m_m68k_&\on&\sz&_ram, m_m68k_&\on&\sz&_ram @ - 0xefffff
55 .long m_m68k_&\on&\sz&_ram, m_m68k_&\on&\sz&_ram, m_m68k_&\on&\sz&_ram, m_m68k_&\on&\sz&_ram @ 0xf00000
56 .long m_m68k_&\on&\sz&_ram, m_m68k_&\on&\sz&_ram, m_m68k_&\on&\sz&_ram, m_m68k_&\on&\sz&_ram @ - 0xffffff
57.endm
58
59.macro mk_s68k_jump_table on sz @ operation name, size
60 .long m_s68k_&\on&\sz&_prg, m_s68k_&\on&\sz&_prg, m_s68k_&\on&\sz&_prg, m_s68k_&\on&\sz&_prg @ 0x000000 - 0x07ffff
61 .long m_s68k_&\on&\sz&_wordram_2M @ 0x080000 - 0x09ffff
62 .long m_s68k_&\on&\sz&_wordram_2M @ 0x0a0000 - 0x0bffff
63 .long m_&\on&_null @ 0x0c0000 - 0x0dffff, 1M area
64 .long m_&\on&_null @ 0x0e0000 - 0x0fffff
65.endm
66
67
68@ the jumptables themselves.
69m_m68k_read8_table: mk_m68k_jump_table read 8
70m_m68k_read16_table: mk_m68k_jump_table read 16
71m_m68k_read32_table: mk_m68k_jump_table read 32
72m_m68k_write8_table: mk_m68k_jump_table write 8
73m_m68k_write16_table: mk_m68k_jump_table write 16
74m_m68k_write32_table: mk_m68k_jump_table write 32
75
76m_s68k_read8_table: mk_s68k_jump_table read 8
77m_s68k_read16_table: mk_s68k_jump_table read 16
78m_s68k_read32_table: mk_s68k_jump_table read 32
79m_s68k_write8_table: mk_s68k_jump_table write 8
80m_s68k_write16_table: mk_s68k_jump_table write 16
81m_s68k_write32_table: mk_s68k_jump_table write 32
82
83m_s68k_decode_write_table:
84 .long m_s68k_write8_2M_decode_b0_m0
85 .long m_s68k_write16_2M_decode_b0_m0
86 .long m_s68k_write32_2M_decode_b0_m0
87 .long m_s68k_write8_2M_decode_b0_m1
88 .long m_s68k_write16_2M_decode_b0_m1
89 .long m_s68k_write32_2M_decode_b0_m1
90 .long m_s68k_write8_2M_decode_b0_m2
91 .long m_s68k_write16_2M_decode_b0_m2
92 .long m_s68k_write32_2M_decode_b0_m2
93 .long m_s68k_write8_2M_decode_b1_m0
94 .long m_s68k_write16_2M_decode_b1_m0
95 .long m_s68k_write32_2M_decode_b1_m0
96 .long m_s68k_write8_2M_decode_b1_m1
97 .long m_s68k_write16_2M_decode_b1_m1
98 .long m_s68k_write32_2M_decode_b1_m1
99 .long m_s68k_write8_2M_decode_b1_m2
100 .long m_s68k_write16_2M_decode_b1_m2
101 .long m_s68k_write32_2M_decode_b1_m2
102
103
104@ @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
105
106.text
107.align 4
108
109.global PicoMemResetCD
110.global PicoMemResetCDdecode
111.global PicoReadM68k8
112.global PicoReadM68k16
113.global PicoReadM68k32
114.global PicoWriteM68k8
115.global PicoWriteM68k16
116.global PicoWriteM68k32
117.global PicoReadS68k8
118.global PicoReadS68k16
119.global PicoReadS68k32
120.global PicoWriteS68k8
121.global PicoWriteS68k16
122.global PicoWriteS68k32
123
124@ externs, just for reference
125.extern Pico
126.extern z80Read8
127.extern OtherRead16
128.extern PicoVideoRead
129.extern Read_CDC_Host
130.extern m68k_reg_write8
131.extern OtherWrite8
132.extern OtherWrite16
133.extern gfx_cd_read
134.extern s68k_reg_read16
135.extern SRam
136.extern gfx_cd_write16
137.extern s68k_reg_write8
138.extern s68k_poll_adclk
139.extern PicoCpuS68k
140.extern s68k_poll_detect
141.extern SN76496Write
142.extern m_m68k_read8_misc
143.extern m_m68k_write8_misc
144
145
146@ r0=reg3, r1-r3=temp
147.macro mk_update_table on sz @ operation name, size
148 @ we only set word-ram handlers
149 ldr r1, =m_m68k_&\on&\sz&_table
150 ldr r12,=m_s68k_&\on&\sz&_table
151 tst r0, #4
152 bne 0f @ pmr_8_1M
153
154@ pmr_8_2M:
155 ldr r2, =m_m68k_&\on&\sz&_wordram0_2M
156 ldr r3, =m_s68k_&\on&\sz&_wordram_2M
157 str r2, [r1, #16*4]
158 str r2, [r1, #17*4]
159 ldr r2, =m_&\on&_null
160 str r3, [r12,#4*4]
161 str r3, [r12,#5*4]
162 str r2, [r12,#6*4]
163 b 9f @ pmr_8_done
164
1650: @ pmr_8_1M:
166 tst r0, #1
167 bne 1f @ pmr_8_1M1
168
169@ pmr_8_1M0:
170 ldr r2, =m_m68k_&\on&\sz&_wordram0_1M_b0
171 ldr r3, =m_m68k_&\on&\sz&_wordram1_1M_b0
172 str r2, [r1, #16*4]
173 str r3, [r1, #17*4]
174 ldr r3, =m_s68k_&\on&\sz&_wordram_1M_b1
175.ifeqs "\on", "read"
176 ldr r2, =m_s68k_&\on&\sz&_wordram_2M_decode_b1
177 str r2, [r12,#4*4]
178 str r2, [r12,#5*4]
179.endif
180 str r3, [r12,#6*4]
181 b 9f @ pmr_8_done
182
1831: @ pmr_8_1M1:
184 ldr r2, =m_m68k_&\on&\sz&_wordram0_1M_b1
185 ldr r3, =m_m68k_&\on&\sz&_wordram1_1M_b1
186 str r2, [r1, #16*4]
187 str r3, [r1, #17*4]
188 ldr r3, =m_s68k_&\on&\sz&_wordram_1M_b0
189.ifeqs "\on", "read"
190 ldr r2, =m_s68k_&\on&\sz&_wordram_2M_decode_b0
191 str r2, [r12,#4*4]
192 str r2, [r12,#5*4]
193.endif
194 str r3, [r12,#6*4]
195
1969: @ pmr_8_done:
197.endm
198
199
200PicoMemResetCD: @ r3
201 mk_update_table read 8
202 mk_update_table read 16
203 mk_update_table read 32
204 mk_update_table write 8
205 mk_update_table write 16
206 mk_update_table write 32
207 bx lr
208
209
210PicoMemResetCDdecode: @reg3
211 tst r0, #4
212 bxeq lr @ we should not be called in 2M mode
213 ldr r1, =m_s68k_write8_table
214 ldr r3, =m_s68k_decode_write_table
215 and r2, r0, #0x18
216 mov r2, r2, lsr #3
217 cmp r2, #3
218 moveq r2, #2 @ mode3 is same as mode2?
219 tst r0, #1
220 addeq r2, r2, #3 @ bank1 (r2=0..5)
221 add r2, r2, r2, lsl #1 @ *= 3
222 add r2, r3, r2, lsl #2
223 ldmia r2, {r0,r3,r12}
224 str r0, [r1, #4*4]
225 str r0, [r1, #5*4]
226 str r3, [r1, #4*4+8*4]
227 str r3, [r1, #5*4+8*4]
228 str r12,[r1, #4*4+8*4*2]
229 str r12,[r1, #5*4+8*4*2]
230 bx lr
231
232
233.pool
234
235@ @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
236
237.macro mk_entry_m68k table
238 ldr r2, =\table
239 bic r0, r0, #0xff000000
240 and r3, r0, #0x00fe0000
241 ldr pc, [r2, r3, lsr #15]
242.endm
243
244PicoReadM68k8: @ u32 a
245 mk_entry_m68k m_m68k_read8_table
246
247PicoReadM68k16: @ u32 a
248 mk_entry_m68k m_m68k_read16_table
249
250PicoReadM68k32: @ u32 a
251 mk_entry_m68k m_m68k_read32_table
252
253PicoWriteM68k8: @ u32 a, u8 d
254 mk_entry_m68k m_m68k_write8_table
255
256PicoWriteM68k16: @ u32 a, u16 d
257 mk_entry_m68k m_m68k_write16_table
258
259PicoWriteM68k32: @ u32 a, u32 d
260 mk_entry_m68k m_m68k_write32_table
261
262
263.macro mk_entry_s68k on sz
264 bic r0, r0, #0xff000000
265 cmp r0, #0x00080000
266 blt m_s68k_&\on&\sz&_prg
267 cmp r0, #0x000e0000
268 ldrlt r2, =m_s68k_&\on&\sz&_table
269 andlt r3, r0, #0x000e0000
270 ldrlt pc, [r2, r3, lsr #15]
271 mov r3, #0x00ff0000
272 orr r3, r3, #0x00008000
273 cmp r0, r3
274 bge m_s68k_&\on&\sz&_regs
275 cmp r0, #0x00ff0000
276 bge m_s68k_&\on&\sz&_pcm
277 cmp r0, #0x00fe0000
278 bge m_s68k_&\on&\sz&_backup
279 mov r0, #0
280 bx lr
281.endm
282
283PicoReadS68k8: @ u32 a
284 mk_entry_s68k read 8
285
286PicoReadS68k16: @ u32 a
287 mk_entry_s68k read 16
288
289PicoReadS68k32: @ u32 a
290 mk_entry_s68k read 32
291
292PicoWriteS68k8: @ u32 a, u8 d
293 mk_entry_s68k write 8
294
295PicoWriteS68k16: @ u32 a, u16 d
296 mk_entry_s68k write 16
297
298PicoWriteS68k32: @ u32 a, u32 d
299 mk_entry_s68k write 32
300
301
302.pool
303
304@ @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
305
306@ utilities
307
308@ r0=addr[in,out], r1,r2=tmp
309.macro cell_map
310 ands r1, r0, #0x01c000
311 ldrne pc, [pc, r1, lsr #12]
312 beq 0f @ most common?
313 .long 0f
314 .long 0f
315 .long 0f
316 .long 0f
317 .long 1f
318 .long 1f
319 .long 2f
320 .long 3f
3211: @ x16 cells
322 and r1, r0, #0x7e00 @ col
323 and r2, r0, #0x01fc @ row
324 orr r2, r2, #0x0400
325 orr r1, r2, r1, ror #13
326 b 9f
3272: @ x8 cells
328 and r1, r0, #0x3f00 @ col
329 and r2, r0, #0x00fc @ row
330 orr r2, r2, #0x0600
331 orr r1, r2, r1, ror #12
332 b 9f
3333: @ x4 cells
334 and r1, r0, #0x1f80 @ col
335 and r2, r0, #0x007c @ row
336 orr r1, r2, r1, ror #11
337 and r2, r0,#0x1e000
338 orr r1, r1, r2, lsr #6
339 b 9f
3400: @ x32 cells
341 and r1, r0, #0xfc00 @ col
342 and r2, r0, #0x03fc @ row
343 orr r1, r2, r1, ror #14
3449:
345 and r0, r0, #3
346 orr r0, r0, r1, ror #26 @ rol 4+2
347.endm
348
349
350@ r0=prt1, r1=ptr2; unaligned ptr MUST be r0
351.macro m_read32_gen
352 tst r0, #2
353 ldrneh r0, [r1, r0]!
354 ldrneh r1, [r1, #2]
355 ldreq r0, [r1, r0]
356 moveq r0, r0, ror #16
357 orrne r0, r1, r0, lsl #16
358.endm
359
360
361@ r0=prt1, r1=data, r2=ptr2; unaligned ptr MUST be r0
362.macro m_write32_gen
363 tst r0, #2
364 mov r1, r1, ror #16
365 strneh r1, [r2, r0]!
366 movne r1, r1, lsr #16
367 strneh r1, [r2, #2]
368 streq r1, [r2, r0]
369.endm
370
371@
372.macro bcram_reg_rw is_read addr_check
373 rsb r0, r0, #0x800000
374 ldr r2, =(Pico+0x22200)
375 cmp r0, #(0x800000-\addr_check)
376 ldreq r2, [r2]
377.if \is_read
378 movne r0, #0
379.endif
380 bxne lr
381 add r2, r2, #0x110000
382 add r2, r2, #0x002200
383.if \is_read
384 ldrb r0, [r2, #0x18]
385.else
386 strb r1, [r2, #0x18]
387.endif
388 bx lr
389.endm
390
391@ @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
392
393
394m_read_null:
395 mov r0, #0
396 bx lr
397
398
399m_m68k_read8_bios:
400 ldr r1, =(Pico+0x22200)
401 bic r0, r0, #0xfe0000
402 ldr r1, [r1]
403 eor r0, r0, #1
404 ldrb r0, [r1, r0]
405 bx lr
406
407
408m_m68k_read8_prgbank:
409 ldr r1, =(Pico+0x22200)
410 eor r0, r0, #1
411 ldr r1, [r1]
412 mov r2, #0x110000
413 orr r3, r2, #0x002200
414 ldr r3, [r1, r3]
415 ldr r2, [r1, r2]
416 and r3, r3, #0x00030000
417 cmp r3, #0x00010000 @ have bus or in reset state?
418 moveq r0, #0
419 bxeq lr
420 and r2, r2, #0xc0000000 @ r3 & 0xC0
421 add r1, r1, r2, lsr #12
422 ldrb r0, [r1, r0]
423 bx lr
424
425
426m_m68k_read8_wordram0_2M: @ 0x200000 - 0x21ffff
427m_m68k_read8_wordram1_2M: @ 0x220000 - 0x23ffff
428 ldr r1, =(Pico+0x22200)
429 sub r0, r0, #0x160000 @ map to our offset, which is 0x0a0000
430 ldr r1, [r1]
431 eor r0, r0, #1
432 ldrb r0, [r1, r0]
433 bx lr
434
435
436m_m68k_read8_wordram0_1M_b0: @ 0x200000 - 0x21ffff
437 ldr r1, =(Pico+0x22200)
438 sub r0, r0, #0x140000 @ map to our offset, which is 0x0c0000
439 ldr r1, [r1]
440 eor r0, r0, #1
441 ldrb r0, [r1, r0]
442 bx lr
443
444
445m_m68k_read8_wordram0_1M_b1: @ 0x200000 - 0x21ffff
446 ldr r1, =(Pico+0x22200)
447 sub r0, r0, #0x120000 @ map to our offset, which is 0x0e0000
448 ldr r1, [r1]
449 eor r0, r0, #1
450 ldrb r0, [r1, r0]
451 bx lr
452
453
454m_m68k_read8_wordram1_1M_b0: @ 0x220000 - 0x23ffff, cell arranged
455 cell_map
456 ldr r1, =(Pico+0x22200)
457 add r0, r0, #0x0c0000
458 ldr r1, [r1]
459 eor r0, r0, #1
460 ldrb r0, [r1, r0]
461 bx lr
462
463
464m_m68k_read8_wordram1_1M_b1: @ 0x220000 - 0x23ffff, cell arranged
465 cell_map
466 ldr r1, =(Pico+0x22200)
467 add r0, r0, #0x0e0000
468 ldr r1, [r1]
469 eor r0, r0, #1
470 ldrb r0, [r1, r0]
471 bx lr
472
473
474m_m68k_read8_bcram_size: @ 0x400000
475 sub r0, r0, #1
476 cmp r0, #0x400000
477 ldreq r1, =SRam
478 mov r0, #0
479 ldreq r1, [r1]
480 bxne lr
481 tst r1, r1
482 movne r0, #3 @ pretend to be a 64k cart (8<<3)
483 bx lr
484
485
486m_m68k_read8_bcram: @ 0x600000 - 0x61ffff
487 ldr r1, =SRam
488 bic r0, r0, #0xfe0000
489 ldr r1, [r1]
490 mov r0, r0, lsr #1
491 tst r1, r1
492 moveq r0, #0
493 bxeq lr
494 add r1, r1, #0x2000
495 ldrb r0, [r1, r0]
496 bx lr
497
498
499m_m68k_read8_bcram_reg: @ 0x7fffff
500 bcram_reg_rw 1, 0x7fffff
501
502
503m_m68k_read8_system_io:
504 bic r2, r0, #0xfe0000
505 bic r2, r2, #0x3f
506 cmp r2, #0x012000
507 bne m_m68k_read8_misc @ now from Pico/Memory.s
508
509 ldr r1, =(Pico+0x22200)
510 and r0, r0, #0x3f
511 ldr r1, [r1] @ Pico.mcd (used everywhere)
512 cmp r0, #0x0e
513 ldrlt pc, [pc, r0, lsl #2]
514 b m_m68k_read8_hi
515 .long m_m68k_read8_r00
516 .long m_m68k_read8_r01
517 .long m_m68k_read8_r02
518 .long m_m68k_read8_r03
519 .long m_m68k_read8_r04
520 .long m_read_null @ unused bits
521 .long m_m68k_read8_r06
522 .long m_m68k_read8_r07
523 .long m_m68k_read8_r08
524 .long m_m68k_read8_r09
525 .long m_read_null @ reserved
526 .long m_read_null
527 .long m_m68k_read8_r0c
528 .long m_m68k_read8_r0d
529m_m68k_read8_r00:
530 add r1, r1, #0x110000
531 ldr r0, [r1, #0x30]
532 and r0, r0, #0x04000000 @ we need irq2 mask state
533 mov r0, r0, lsr #19
534 bx lr
535m_m68k_read8_r01:
536 add r1, r1, #0x110000
537 add r1, r1, #0x002200
538 ldrb r0, [r1, #2] @ Pico_mcd->m.busreq
539 bx lr
540m_m68k_read8_r02:
541 add r1, r1, #0x110000
542 ldrb r0, [r1, #2]
543 bx lr
544m_m68k_read8_r03:
545 add r1, r1, #0x110000
546 ldrb r0, [r1, #3]
547 add r1, r1, #0x002200
548 ldr r1, [r1, #4]
549 and r0, r0, #0xc7
550 tst r1, #2 @ DMNA pending?
551 bxeq lr
552 bic r0, r0, #1
553 orr r0, r0, #2
554 bx lr
555m_m68k_read8_r04:
556 add r1, r1, #0x110000
557 ldrb r0, [r1, #4]
558 bx lr
559m_m68k_read8_r06:
560 ldrb r0, [r1, #0x73] @ IRQ vector
561 bx lr
562m_m68k_read8_r07:
563 ldrb r0, [r1, #0x72]
564 bx lr
565m_m68k_read8_r08:
566 mov r0, #0
567 bl Read_CDC_Host @ TODO: make it local
568 mov r0, r0, lsr #8
569 bx lr
570m_m68k_read8_r09:
571 mov r0, #0
572 b Read_CDC_Host
573m_m68k_read8_r0c:
574 add r1, r1, #0x110000
575 add r1, r1, #0x002200
576 ldr r0, [r1, #0x14] @ Pico_mcd->m.timer_stopwatch
577 mov r0, r0, lsr #24
578 bx lr
579m_m68k_read8_r0d:
580 add r1, r1, #0x110000
581 add r1, r1, #0x002200
582 ldr r0, [r1, #0x14]
583 mov r0, r0, lsr #16
584 bx lr
585m_m68k_read8_hi:
586 cmp r0, #0x30
587 movge r0, #0
588 bxeq lr
589 add r1, r1, #0x110000
590 ldrb r0, [r1, r0]
591 bx lr
592
593/*
594m_m68k_read8_misc:
595 bic r2, r0, #0x00ff
596 bic r2, r2, #0xbf00
597 cmp r2, #0xa00000 @ Z80 RAM?
598 beq z80Read8
599@ ldreq r2, =z80Read8
600@ bxeq r2
601 stmfd sp!,{r0,lr}
602 bic r0, r0, #1
603 mov r1, #8
604 bl OtherRead16 @ non-MCD version should be ok too
605 ldmfd sp!,{r1,lr}
606 tst r1, #1
607 moveq r0, r0, lsr #8
608 bx lr
609*/
610
611m_m68k_read8_vdp:
612 tst r0, #0x70000
613 tsteq r0, #0x000e0
614 bxne lr @ invalid read
615 stmfd sp!,{r0,lr}
616 bic r0, r0, #1
617 bl PicoVideoRead @ TODO: implement it in asm
618 ldmfd sp!,{r1,lr}
619 tst r1, #1
620 moveq r0, r0, lsr #8
621 bx lr
622
623
624m_m68k_read8_ram:
625 ldr r1, =Pico
626 bic r0, r0, #0xff0000
627 eor r0, r0, #1
628 ldrb r0, [r1, r0]
629 bx lr
630
631
632@ @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
633
634
635m_m68k_read16_bios:
636 ldr r1, =(Pico+0x22200)
637 bic r0, r0, #0xfe0000
638 ldr r1, [r1]
639 bic r0, r0, #1
640 ldrh r0, [r1, r0]
641 bx lr
642
643
644m_m68k_read16_prgbank:
645 ldr r1, =(Pico+0x22200)
646 bic r0, r0, #1
647 ldr r1, [r1]
648 mov r2, #0x110000
649 orr r3, r2, #0x002200
650 ldr r3, [r1, r3]
651 ldr r2, [r1, r2]
652 and r3, r3, #0x00030000
653 cmp r3, #0x00010000 @ have bus or in reset state?
654 moveq r0, #0
655 bxeq lr
656 and r2, r2, #0xc0000000 @ r3 & 0xC0
657 add r1, r1, r2, lsr #12
658 ldrh r0, [r1, r0]
659 bx lr
660
661
662m_m68k_read16_wordram0_2M: @ 0x200000 - 0x21ffff
663m_m68k_read16_wordram1_2M: @ 0x220000 - 0x23ffff
664 ldr r1, =(Pico+0x22200)
665 sub r0, r0, #0x160000 @ map to our offset, which is 0x0a0000
666 ldr r1, [r1]
667 bic r0, r0, #1
668 ldrh r0, [r1, r0]
669 bx lr
670
671
672m_m68k_read16_wordram0_1M_b0: @ 0x200000 - 0x21ffff
673 ldr r1, =(Pico+0x22200)
674 sub r0, r0, #0x140000 @ map to our offset, which is 0x0c0000
675 ldr r1, [r1]
676 bic r0, r0, #1
677 ldrh r0, [r1, r0]
678 bx lr
679
680
681m_m68k_read16_wordram0_1M_b1: @ 0x200000 - 0x21ffff
682 ldr r1, =(Pico+0x22200)
683 sub r0, r0, #0x120000 @ map to our offset, which is 0x0e0000
684 ldr r1, [r1]
685 bic r0, r0, #1
686 ldrh r0, [r1, r0]
687 bx lr
688
689
690m_m68k_read16_wordram1_1M_b0: @ 0x220000 - 0x23ffff, cell arranged
691 @ Warning: read32 relies on NOT using r3 and r12 here
692 cell_map
693 ldr r1, =(Pico+0x22200)
694 add r0, r0, #0x0c0000
695 ldr r1, [r1]
696 bic r0, r0, #1
697 ldrh r0, [r1, r0]
698 bx lr
699
700
701m_m68k_read16_wordram1_1M_b1: @ 0x220000 - 0x23ffff, cell arranged
702 cell_map
703 ldr r1, =(Pico+0x22200)
704 add r0, r0, #0x0e0000
705 ldr r1, [r1]
706 bic r0, r0, #1
707 ldrh r0, [r1, r0]
708 bx lr
709
710
711m_m68k_read16_bcram_size: @ 0x400000
712 cmp r0, #0x400000
713 ldreq r1, =SRam
714 mov r0, #0
715 ldreq r1, [r1]
716 bxne lr
717 tst r1, r1
718 movne r0, #3 @ pretend to be a 64k cart
719 bx lr
720
721
722@ m_m68k_read16_bcram: @ 0x600000 - 0x61ffff
723.equiv m_m68k_read16_bcram, m_m68k_read8_bcram
724
725
726m_m68k_read16_bcram_reg: @ 0x7fffff
727 bcram_reg_rw 1, 0x7ffffe
728
729
730m_m68k_read16_system_io:
731 bic r1, r0, #0xfe0000
732 bic r1, r1, #0x3f
733 cmp r1, #0x012000
734 bne m_m68k_read16_misc
735
736m_m68k_read16_m68k_regs:
737 ldr r1, =(Pico+0x22200)
738 and r0, r0, #0x3e
739 ldr r1, [r1] @ Pico.mcd (used everywhere)
740 cmp r0, #0x0e
741 ldrlt pc, [pc, r0, lsl #1]
742 b m_m68k_read16_hi
743 .long m_m68k_read16_r00
744 .long m_m68k_read16_r02
745 .long m_m68k_read16_r04
746 .long m_m68k_read16_r06
747 .long m_m68k_read16_r08
748 .long m_read_null @ reserved
749 .long m_m68k_read16_r0c
750m_m68k_read16_r00:
751 add r1, r1, #0x110000
752 ldr r0, [r1, #0x30]
753 add r1, r1, #0x002200
754 ldrb r1, [r1, #2] @ Pico_mcd->m.busreq
755 and r0, r0, #0x04000000 @ we need irq2 mask state
756 orr r0, r1, r0, lsr #11
757 bx lr
758m_m68k_read16_r02:
759 add r1, r1, #0x110000
760 ldrb r0, [r1, #2]
761 ldrb r2, [r1, #3]
762 add r1, r1, #0x002200
763 ldr r1, [r1, #4]
764 and r2, r2, #0xc7
765 orr r0, r2, r0, lsl #8
766 tst r1, #2 @ DMNA pending?
767 bxeq lr
768 bic r0, r0, #1
769 orr r0, r0, #2
770 bx lr
771m_m68k_read16_r04:
772 add r1, r1, #0x110000
773 ldrb r0, [r1, #4]
774 mov r0, r0, lsl #8
775 bx lr
776m_m68k_read16_r06:
777 ldrh r0, [r1, #0x72] @ IRQ vector
778 bx lr
779m_m68k_read16_r08:
780 mov r0, #0
781 b Read_CDC_Host
782m_m68k_read16_r0c:
783 add r1, r1, #0x110000
784 add r1, r1, #0x002200
785 ldr r0, [r1, #0x14]
786 mov r0, r0, lsr #16
787 bx lr
788m_m68k_read16_hi:
789 cmp r0, #0x30
790 addlt r1, r1, #0x110000
791 ldrlth r1, [r1, r0]
792 movge r0, #0
793 bxge lr
794 mov r0, r1, lsr #8
795 and r1, r1, #0xff
796 orr r0, r0, r1, lsl #8
797 bx lr
798
799
800m_m68k_read16_misc:
801 bic r0, r0, #1
802 mov r1, #16
803 b OtherRead16
804
805
806m_m68k_read16_vdp:
807 tst r0, #0x70000
808 tsteq r0, #0x000e0
809 bxne lr @ invalid read
810 bic r0, r0, #1
811 b PicoVideoRead
812
813
814m_m68k_read16_ram:
815 ldr r1, =Pico
816 bic r0, r0, #0xff0000
817 bic r0, r0, #1
818 ldrh r0, [r1, r0]
819 bx lr
820
821
822@ @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
823
824
825m_m68k_read32_bios:
826 ldr r1, =(Pico+0x22200)
827 bic r0, r0, #0xfe0000
828 ldr r1, [r1]
829 bic r0, r0, #1
830 m_read32_gen
831 bx lr
832
833
834m_m68k_read32_prgbank:
835 ldr r1, =(Pico+0x22200)
836 bic r0, r0, #1
837 ldr r1, [r1]
838 mov r2, #0x110000
839 orr r3, r2, #0x002200
840 ldr r3, [r1, r3]
841 ldr r2, [r1, r2]
842 and r3, r3, #0x00030000
843 cmp r3, #0x00010000 @ have bus or in reset state?
844 moveq r0, #0
845 bxeq lr
846 and r2, r2, #0xc0000000 @ r3 & 0xC0
847 add r1, r1, r2, lsr #12
848 m_read32_gen
849 bx lr
850
851
852m_m68k_read32_wordram0_2M: @ 0x200000 - 0x21ffff
853m_m68k_read32_wordram1_2M: @ 0x220000 - 0x23ffff
854 ldr r1, =(Pico+0x22200)
855 sub r0, r0, #0x160000 @ map to our offset, which is 0x0a0000
856 ldr r1, [r1]
857 bic r0, r0, #1
858 m_read32_gen
859 bx lr
860
861
862m_m68k_read32_wordram0_1M_b0: @ 0x200000 - 0x21ffff
863 ldr r1, =(Pico+0x22200)
864 sub r0, r0, #0x140000 @ map to our offset, which is 0x0c0000
865 ldr r1, [r1]
866 bic r0, r0, #1
867 m_read32_gen
868 bx lr
869
870
871m_m68k_read32_wordram0_1M_b1: @ 0x200000 - 0x21ffff
872 ldr r1, =(Pico+0x22200)
873 sub r0, r0, #0x120000 @ map to our offset, which is 0x0e0000
874 ldr r1, [r1]
875 bic r0, r0, #1
876 m_read32_gen
877 bx lr
878
879
880m_m68k_read32_wordram1_1M_b0: @ 0x220000 - 0x23ffff, cell arranged
881 tst r0, #2
882 bne m_m68k_read32_wordram1_1M_b0_unal
883 cell_map
884 ldr r1, =(Pico+0x22200)
885 add r0, r0, #0x0c0000
886 ldr r1, [r1]
887 bic r0, r0, #1
888 m_read32_gen
889 bx lr
890m_m68k_read32_wordram1_1M_b0_unal:
891 @ hopefully this doesn't happen too often
892 mov r12,lr
893 mov r3, r0
894 bl m_m68k_read16_wordram1_1M_b0 @ must not trash r12 and r3
895 add r1, r3, #2
896 mov r3, r0
897 mov r0, r1
898 bl m_m68k_read16_wordram1_1M_b0
899 orr r0, r0, r3, lsl #16
900 bx r12
901
902
903m_m68k_read32_wordram1_1M_b1: @ 0x220000 - 0x23ffff, cell arranged
904 tst r0, #2
905 bne m_m68k_read32_wordram1_1M_b1_unal
906 cell_map
907 ldr r1, =(Pico+0x22200)
908 add r0, r0, #0x0e0000
909 ldr r1, [r1]
910 bic r0, r0, #1
911 m_read32_gen
912 bx lr
913m_m68k_read32_wordram1_1M_b1_unal:
914 mov r12,lr
915 mov r3, r0
916 bl m_m68k_read16_wordram1_1M_b1 @ must not trash r12 and r3
917 add r1, r3, #2
918 mov r3, r0
919 mov r0, r1
920 bl m_m68k_read16_wordram1_1M_b1
921 orr r0, r0, r3, lsl #16
922 bx r12
923
924
925m_m68k_read32_bcram_size: @ 0x400000
926 cmp r0, #0x400000
927 ldreq r1, =SRam
928 mov r0, #0
929 ldreq r1, [r1]
930 bxne lr
931 tst r1, r1
932 movne r0, #0x30000 @ pretend to be a 64k cart
933 bx lr
934
935
936m_m68k_read32_bcram: @ 0x600000 - 0x61ffff, not likely to be called
937 mov r12,lr
938 add r3, r0, #2
939 bl m_m68k_read8_bcram
940 mov r1, r0
941 mov r0, r3
942 mov r3, r1
943 bl m_m68k_read8_bcram
944 orr r0, r0, r3, lsl #16
945 bx r12
946
947
948m_m68k_read32_bcram_reg: @ 0x7fffff
949 bcram_reg_rw 1, 0x7ffffc
950
951
952@ it is not very practical to use long access on hw registers, so I assume it is not used too much.
953m_m68k_read32_system_io:
954 bic r1, r0, #0xfe0000
955 bic r1, r1, #0x3f
956 cmp r1, #0x012000
957 bne m_m68k_read32_misc
958 and r1, r0, #0x3e
959 cmp r1, #0x0e
960 blt m_m68k_read32_misc
961 cmp r1, #0x30
962 movge r0, #0
963 bxge lr
964 @ I have seen the range 0x0e-0x2f accessed quite frequently with long i/o, so here is some code for that
965 mov r0, r1
966 ldr r1, =(Pico+0x22200)
967 mov r2, #0xff
968 ldr r1, [r1]
969 orr r2, r2, r2, lsl #16
970 add r1, r1, #0x110000
971 m_read32_gen
972 and r1, r2, r0 @ data is big-endian read as little, have to byteswap
973 and r0, r2, r0, lsr #8
974 orr r0, r0, r1, lsl #8
975 bx lr
976
977m_m68k_read32_misc:
978 add r1, r0, #2
979 stmfd sp!,{r1,lr}
980 bl m_m68k_read16_system_io
981 swp r0, r0, [sp]
982 bl m_m68k_read16_system_io
983 ldmfd sp!,{r1,lr}
984 orr r0, r0, r1, lsl #16
985 bx lr
986
987
988m_m68k_read32_vdp:
989 tst r0, #0x70000
990 tsteq r0, #0x000e0
991 bxne lr @ invalid read
992 bic r0, r0, #1
993 add r1, r0, #2
994 stmfd sp!,{r1,lr}
995 bl PicoVideoRead
996 swp r0, r0, [sp]
997 bl PicoVideoRead
998 ldmfd sp!,{r1,lr}
999 orr r0, r0, r1, lsl #16
1000 bx lr
1001
1002
1003m_m68k_read32_ram:
1004 ldr r1, =Pico
1005 bic r0, r0, #0xff0000
1006 bic r0, r0, #1
1007 m_read32_gen
1008 bx lr
1009
1010.pool
1011
1012@ @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
1013
1014
1015m_write_null:
1016m_m68k_write8_bios:
1017m_m68k_write8_bcram_size: @ 0x400000
1018 bx lr
1019
1020
1021m_m68k_write8_prgbank:
1022 ldr r2, =(Pico+0x22200)
1023 eor r0, r0, #1
1024 ldr r2, [r2]
1025 mov r12,#0x110000
1026 orr r3, r12, #0x002200
1027 ldr r3, [r2, r3]
1028 ldr r12,[r2, r12]
1029 and r3, r3, #0x00030000
1030 cmp r3, #0x00010000 @ have bus or in reset state?
1031 bxeq lr
1032 and r12,r12,#0xc0000000 @ r3 & 0xC0
1033 add r2, r2, r12, lsr #12
1034 strb r1, [r2, r0]
1035 bx lr
1036
1037
1038m_m68k_write8_wordram0_2M: @ 0x200000 - 0x21ffff
1039m_m68k_write8_wordram1_2M: @ 0x220000 - 0x23ffff
1040 ldr r2, =(Pico+0x22200)
1041 sub r0, r0, #0x160000 @ map to our offset, which is 0x0a0000
1042 ldr r2, [r2]
1043 eor r0, r0, #1
1044 strb r1, [r2, r0]
1045 bx lr
1046
1047
1048m_m68k_write8_wordram0_1M_b0: @ 0x200000 - 0x21ffff
1049 ldr r2, =(Pico+0x22200)
1050 sub r0, r0, #0x140000 @ map to our offset, which is 0x0c0000
1051 ldr r2, [r2]
1052 eor r0, r0, #1
1053 strb r1, [r2, r0]
1054 bx lr
1055
1056
1057m_m68k_write8_wordram0_1M_b1: @ 0x200000 - 0x21ffff
1058 ldr r2, =(Pico+0x22200)
1059 sub r0, r0, #0x120000 @ map to our offset, which is 0x0e0000
1060 ldr r2, [r2]
1061 eor r0, r0, #1
1062 strb r1, [r2, r0]
1063 bx lr
1064
1065
1066m_m68k_write8_wordram1_1M_b0: @ 0x220000 - 0x23ffff, cell arranged
1067 mov r3, r1
1068 cell_map
1069 ldr r2, =(Pico+0x22200)
1070 add r0, r0, #0x0c0000
1071 ldr r2, [r2]
1072 eor r0, r0, #1
1073 strb r3, [r2, r0]
1074 bx lr
1075
1076
1077m_m68k_write8_wordram1_1M_b1: @ 0x220000 - 0x23ffff, cell arranged
1078 mov r3, r1
1079 cell_map
1080 ldr r2, =(Pico+0x22200)
1081 add r0, r0, #0x0e0000
1082 ldr r2, [r2]
1083 eor r0, r0, #1
1084 strb r3, [r2, r0]
1085 bx lr
1086
1087
1088m_m68k_write8_bcram: @ 0x600000 - 0x61ffff
1089 @ can't use r3 or r12, because of write32
1090 ldr r2, =SRam
1091 bic r0, r0, #0xfe0000
1092 ldr r2, [r2]
1093 tst r2, r2
1094 bxeq lr
1095 add r0, r2, r0, lsr #1
1096 ldr r2, =(Pico+0x22200)
1097 ldr r2, [r2]
1098 add r0, r0, #0x2000
1099 add r2, r2, #0x110000
1100 add r2, r2, #0x002200
1101 ldr r2, [r2, #0x18]
1102 tst r2, #1 @ check bcram reg
1103 bxeq lr
1104 strb r1, [r0]
1105 ldr r2, =SRam
1106 mov r0, #1
1107 strb r0, [r2, #0x0e] @ SRam.changed = 1
1108 bx lr
1109
1110
1111m_m68k_write8_bcram_reg: @ 0x7fffff
1112 bcram_reg_rw 0, 0x7fffff
1113
1114
1115m_m68k_write8_system_io:
1116 bic r2, r0, #0xfe0000
1117 bic r2, r2, #0x3f
1118 cmp r2, #0x012000
1119 beq m68k_reg_write8
1120 mov r2, #8
1121@ b OtherWrite8
1122 b m_m68k_write8_misc
1123
1124
1125m_m68k_write8_vdp:
1126 tst r0, #0x70000
1127 tsteq r0, #0x000e0
1128 bxne lr @ invalid
1129 and r2, r0, #0x19
1130 cmp r2, #0x11
1131 andeq r0, r1, #0xff
1132 beq SN76496Write
1133 and r1, r1, #0xff
1134 orr r1, r1, r1, lsl #8 @ byte access gets mirrored
1135 b PicoVideoWrite
1136
1137
1138m_m68k_write8_ram:
1139 ldr r2, =Pico
1140 bic r0, r0, #0xff0000
1141 eor r0, r0, #1
1142 strb r1, [r2, r0]
1143 bx lr
1144
1145
1146@ @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
1147
1148
1149m_m68k_write16_bios:
1150m_m68k_write16_bcram_size: @ 0x400000
1151 bx lr
1152
1153
1154m_m68k_write16_prgbank:
1155 ldr r2, =(Pico+0x22200)
1156 bic r0, r0, #1
1157 ldr r2, [r2]
1158 mov r12,#0x110000
1159 orr r3, r12, #0x002200
1160 ldr r3, [r2, r3]
1161 ldr r12,[r2, r12]
1162 and r3, r3, #0x00030000
1163 cmp r3, #0x00010000 @ have bus or in reset state?
1164 bxeq lr
1165 and r12,r12,#0xc0000000 @ r3 & 0xC0
1166 add r2, r2, r12, lsr #12
1167 strh r1, [r2, r0]
1168 bx lr
1169
1170
1171m_m68k_write16_wordram0_2M: @ 0x200000 - 0x21ffff
1172m_m68k_write16_wordram1_2M: @ 0x220000 - 0x23ffff
1173 ldr r2, =(Pico+0x22200)
1174 sub r0, r0, #0x160000 @ map to our offset, which is 0x0a0000
1175 ldr r2, [r2]
1176 bic r0, r0, #1
1177 strh r1, [r2, r0]
1178 bx lr
1179
1180
1181m_m68k_write16_wordram0_1M_b0: @ 0x200000 - 0x21ffff
1182 ldr r2, =(Pico+0x22200)
1183 sub r0, r0, #0x140000 @ map to our offset, which is 0x0c0000
1184 ldr r2, [r2]
1185 bic r0, r0, #1
1186 strh r1, [r2, r0]
1187 bx lr
1188
1189
1190m_m68k_write16_wordram0_1M_b1: @ 0x200000 - 0x21ffff
1191 ldr r2, =(Pico+0x22200)
1192 sub r0, r0, #0x120000 @ map to our offset, which is 0x0e0000
1193 ldr r2, [r2]
1194 bic r0, r0, #1
1195 strh r1, [r2, r0]
1196 bx lr
1197
1198
1199m_m68k_write16_wordram1_1M_b0: @ 0x220000 - 0x23ffff, cell arranged
1200 @ Warning: write32 relies on NOT using r12 and and keeping data in r3
1201 mov r3, r1
1202 cell_map
1203 ldr r1, =(Pico+0x22200)
1204 add r0, r0, #0x0c0000
1205 ldr r1, [r1]
1206 bic r0, r0, #1
1207 strh r3, [r1, r0]
1208 bx lr
1209
1210
1211m_m68k_write16_wordram1_1M_b1: @ 0x220000 - 0x23ffff, cell arranged
1212 mov r3, r1
1213 cell_map
1214 ldr r1, =(Pico+0x22200)
1215 add r0, r0, #0x0e0000
1216 ldr r1, [r1]
1217 bic r0, r0, #1
1218 strh r3, [r1, r0]
1219 bx lr
1220
1221
1222@ m_m68k_write16_bcram: @ 0x600000 - 0x61ffff
1223.equiv m_m68k_write16_bcram, m_m68k_write8_bcram
1224
1225
1226m_m68k_write16_bcram_reg: @ 0x7fffff
1227 bcram_reg_rw 0, 0x7ffffe
1228
1229
1230m_m68k_write16_system_io:
1231 bic r0, r0, #1
1232 bic r2, r0, #0xfe0000
1233 bic r2, r2, #0x3f
1234 cmp r2, #0x012000
1235 bne OtherWrite16
1236
1237m_m68k_write16_regs:
1238 and r0, r0, #0x3e
1239 cmp r0, #0x0e
1240 beq m_m68k_write16_regs_spec
1241 and r3, r1, #0xff
1242 add r2, r0, #1
1243 stmfd sp!,{r2,r3,lr}
1244 mov r1, r1, lsr #8
1245 bl m68k_reg_write8
1246 ldmfd sp!,{r0,r1,lr}
1247 b m68k_reg_write8
1248
1249m_m68k_write16_regs_spec: @ special case
1250 ldr r2, =(Pico+0x22200)
1251 ldr r3, =s68k_poll_adclk
1252 mov r0, #0x110000
1253 ldr r2, [r2]
1254 add r0, r0, #0x00000e
1255 mov r1, r1, lsr #8
1256 strb r1, [r2, r0] @ if (a == 0xe) s68k_regs[0x0e] = d >> 8;
1257 ldr r2, [r3]
1258 mov r1, #0
1259 and r2, r2, #0xfe
1260 cmp r2, #0x0e
1261 bxne lr
1262 ldr r0, =PicoCpuS68k
1263 str r1, [r0, #0x58] @ push s68k out of stopped state
1264 str r1, [r3]
1265 bx lr
1266
1267
1268m_m68k_write16_vdp:
1269 tst r0, #0x70000
1270 tsteq r0, #0x000e0
1271 bxne lr @ invalid
1272 bic r0, r0, #1
1273 and r2, r0, #0x18
1274 cmp r2, #0x10
1275 bne PicoVideoWrite
1276 and r0, r1, #0xff
1277 b SN76496Write @ lsb goes to 0x11
1278
1279
1280m_m68k_write16_ram:
1281 ldr r2, =Pico
1282 bic r0, r0, #0xff0000
1283 bic r0, r0, #1
1284 strh r1, [r2, r0]
1285 bx lr
1286
1287
1288@ @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
1289
1290
1291m_m68k_write32_bios:
1292m_m68k_write32_bcram_size: @ 0x400000
1293 bx lr
1294
1295
1296m_m68k_write32_prgbank:
1297 ldr r2, =(Pico+0x22200)
1298 bic r0, r0, #1
1299 ldr r2, [r2]
1300 mov r12,#0x110000
1301 orr r3, r12, #0x002200
1302 ldr r3, [r2, r3]
1303 ldr r12,[r2, r12]
1304 and r3, r3, #0x00030000
1305 cmp r3, #0x00010000 @ have bus or in reset state?
1306 bxeq lr
1307 and r12,r12,#0xc0000000 @ r3 & 0xC0
1308 add r2, r2, r12, lsr #12
1309 m_write32_gen
1310 bx lr
1311
1312
1313m_m68k_write32_wordram0_2M: @ 0x200000 - 0x21ffff
1314m_m68k_write32_wordram1_2M: @ 0x220000 - 0x23ffff
1315 ldr r2, =(Pico+0x22200)
1316 sub r0, r0, #0x160000 @ map to our offset, which is 0x0a0000
1317 ldr r2, [r2]
1318 bic r0, r0, #1
1319 m_write32_gen
1320 bx lr
1321
1322
1323m_m68k_write32_wordram0_1M_b0: @ 0x200000 - 0x21ffff
1324 ldr r2, =(Pico+0x22200)
1325 sub r0, r0, #0x140000 @ map to our offset, which is 0x0c0000
1326 ldr r2, [r2]
1327 bic r0, r0, #1
1328 m_write32_gen
1329 bx lr
1330
1331
1332m_m68k_write32_wordram0_1M_b1: @ 0x200000 - 0x21ffff
1333 ldr r2, =(Pico+0x22200)
1334 sub r0, r0, #0x120000 @ map to our offset, which is 0x0e0000
1335 ldr r2, [r2]
1336 bic r0, r0, #1
1337 m_write32_gen
1338 bx lr
1339
1340
1341m_m68k_write32_wordram1_1M_b0: @ 0x220000 - 0x23ffff, cell arranged
1342 tst r0, #2
1343 bne m_m68k_write32_wordram1_1M_b0_unal
1344 mov r3, r1
1345 cell_map
1346 ldr r2, =(Pico+0x22200)
1347 add r0, r0, #0x0c0000
1348 ldr r2, [r2]
1349 bic r0, r0, #1
1350 mov r1, r3
1351 m_write32_gen
1352 bx lr
1353m_m68k_write32_wordram1_1M_b0_unal:
1354 @ hopefully this doesn't happen too often
1355 add r12,r0, #2
1356 mov r1, r1, ror #16
1357 stmfd sp!,{lr}
1358 bl m_m68k_write16_wordram1_1M_b0 @ must not trash r12 and keep data in r3
1359 ldmfd sp!,{lr}
1360 mov r0, r12
1361 mov r1, r3, lsr #16
1362 b m_m68k_write16_wordram1_1M_b0
1363
1364
1365m_m68k_write32_wordram1_1M_b1: @ 0x220000 - 0x23ffff, cell arranged
1366 tst r0, #2
1367 bne m_m68k_write32_wordram1_1M_b1_unal
1368 mov r3, r1
1369 cell_map
1370 ldr r2, =(Pico+0x22200)
1371 add r0, r0, #0x0e0000
1372 ldr r2, [r2]
1373 bic r0, r0, #1
1374 mov r1, r3
1375 m_write32_gen
1376 bx lr
1377m_m68k_write32_wordram1_1M_b1_unal:
1378 add r12,r0, #2
1379 mov r1, r1, ror #16
1380 stmfd sp!,{lr}
1381 bl m_m68k_write16_wordram1_1M_b1 @ same as above
1382 ldmfd sp!,{lr}
1383 mov r0, r12
1384 mov r1, r3, lsr #16
1385 b m_m68k_write16_wordram1_1M_b1
1386
1387
1388m_m68k_write32_bcram: @ 0x600000 - 0x61ffff, not likely to be called
1389 mov r12,lr
1390 add r3, r0, #2
1391 mov r1, r1, ror #16
1392 bl m_m68k_write8_bcram
1393 mov r0, r3
1394 mov r1, r1, ror #16
1395 bl m_m68k_write8_bcram
1396 bx r12
1397
1398
1399m_m68k_write32_bcram_reg: @ 0x7fffff
1400 bcram_reg_rw 0, 0x7ffffc
1401
1402
1403
1404@ it is not very practical to use long access on hw registers, so I assume it is not used too much.
1405m_m68k_write32_system_io:
1406 bic r2, r0, #0xfe0000
1407 bic r2, r2, #0x3f
1408 cmp r2, #0x012000
1409 bne m_m68k_write32_misc
1410 and r2, r0, #0x3e
1411 cmp r2, #0x20
1412 bxge lr
1413 cmp r2, #0x10
1414 bge m_m68k_write32_regs_comm
1415 cmp r2, #0x0c
1416 bge m_m68k_write32_regs_spec @ hits the nasty comm reg qiurk
1417
1418 bic r0, r0, #1
1419 stmfd sp!,{r0,r1,lr}
1420 mov r1, r1, lsr #24
1421 bl m68k_reg_write8
1422 ldr r0, [sp]
1423 ldr r1, [sp, #4]
1424 add r0, r0, #1
1425 mov r1, r1, lsr #16
1426 bl m68k_reg_write8
1427 ldr r0, [sp]
1428 ldr r1, [sp, #4]
1429 add r0, r0, #2
1430 mov r1, r1, lsr #8
1431 bl m68k_reg_write8
1432 ldmfd sp!,{r0,r1,lr}
1433 add r0, r0, #3
1434 b m68k_reg_write8
1435
1436m_m68k_write32_regs_comm: @ Handle the 0x10-0x1f range
1437 ldr r0, =(Pico+0x22200)
1438 mov r3, #0xff
1439 ldr r0, [r0]
1440 orr r3, r3, r3, lsl #16
1441 add r0, r0, #0x110000
1442 and r12,r3, r1, ror #16 @ data is big-endian to be written as little, have to byteswap
1443 and r1, r3, r1, ror #24
1444 orr r1, r1, r12,lsl #8 @ end of byteswap
1445 cmp r2, #0x1e
1446 strh r1, [r2, r0]!
1447 ldr r3, =s68k_poll_adclk
1448 ldr r0, [r3]
1449 movne r1, r1, lsr #16
1450 strneh r1, [r2, #2]
1451 cmp r0, #0x10
1452 bxlt lr
1453 ldr r0, =PicoCpuS68k @ remove poll detected state for s68k
1454 mov r1, #0
1455 str r1, [r0, #0x58]
1456 str r1, [r3]
1457 bx lr
1458
1459m_m68k_write32_misc:
1460 bic r0, r0, #1
1461 stmfd sp!,{r0,r1,lr}
1462 mov r1, r1, lsr #16
1463 bl OtherWrite16
1464 ldmfd sp!,{r0,r1,lr}
1465 add r0, r0, #2
1466 b OtherWrite16
1467
1468m_m68k_write32_regs_spec:
1469 bic r0, r0, #1
1470 stmfd sp!,{r0,r1,lr}
1471 mov r1, r1, lsr #16
1472 bl m_m68k_write16_regs
1473 ldmfd sp!,{r0,r1,lr}
1474 add r0, r0, #2
1475 b m_m68k_write16_regs
1476
1477
1478m_m68k_write32_vdp:
1479 tst r0, #0x70000
1480 tsteq r0, #0x000e0
1481 bxne lr @ invalid
1482 and r2, r0, #0x18
1483 cmp r2, #0x10
1484 moveq r0, r1, lsr #16
1485 beq SN76496Write @ which game is crazy enough to do that?
1486 stmfd sp!,{r0,r1,lr}
1487 mov r1, r1, lsr #16
1488 bl PicoVideoWrite
1489 ldmfd sp!,{r0,r1,lr}
1490 add r0, r0, #2
1491 b PicoVideoWrite
1492
1493
1494m_m68k_write32_ram:
1495 ldr r2, =Pico
1496 bic r0, r0, #0xff0000
1497 bic r0, r0, #1
1498 m_write32_gen
1499 bx lr
1500
1501.pool
1502
1503
1504@ @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
1505
1506@ @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
1507
1508
1509.macro m_s68k_read8_ram map_addr
1510 ldr r1, =(Pico+0x22200)
1511 eor r0, r0, #1
1512 ldr r1, [r1]
1513.if \map_addr
1514 add r0, r0, #\map_addr @ map to our address
1515.endif
1516 ldrb r0, [r1, r0]
1517 bx lr
1518.endm
1519
1520.macro m_s68k_read8_wordram_2M_decode map_addr
1521 ldr r2, =(Pico+0x22200)
1522 eor r0, r0, #2
1523 ldr r2, [r2]
1524 movs r0, r0, lsr #1 @ +4-6 <<16
1525 add r2, r2, #\map_addr @ map to our address
1526 ldrb r0, [r2, r0]
1527 movcc r0, r0, lsr #4
1528 andcs r0, r0, #0xf
1529 bx lr
1530.endm
1531
1532
1533m_s68k_read8_prg: @ 0x000000 - 0x07ffff
1534m_s68k_read8_wordram_2M: @ 0x080000 - 0x0bffff
1535m_s68k_read8_wordram_1M_b1: @ 0x0c0000 - 0x0dffff, maps to 0x0e0000
1536 m_s68k_read8_ram 0x020000
1537
1538
1539m_s68k_read8_wordram_2M_decode_b0: @ 0x080000 - 0x0bffff
1540 m_s68k_read8_wordram_2M_decode 0x080000 @ + ^ / 2
1541
1542
1543m_s68k_read8_wordram_2M_decode_b1: @ 0x080000 - 0x0bffff
1544 m_s68k_read8_wordram_2M_decode 0x0a0000 @ + ^ / 2
1545
1546
1547m_s68k_read8_wordram_1M_b0: @ 0x0c0000 - 0x0dffff (same as our offset :)
1548 m_s68k_read8_ram 0
1549
1550
1551m_s68k_read8_backup: @ 0xfe0000 - 0xfe3fff (repeated?)
1552 @ must not trash r3 and r12
1553 ldr r1, =(Pico+0x22200)
1554 mov r0, r0, lsr #1
1555 ldr r1, [r1]
1556 bic r0, r0, #0xff0000
1557 bic r0, r0, #0x00e000
1558 add r1, r1, #0x110000
1559 add r1, r1, #0x000200
1560 ldrb r0, [r1, r0]
1561 bx lr
1562
1563
1564m_s68k_read8_pcm:
1565 @ must not trash r3 and r12
1566 ldr r1, =(Pico+0x22200)
1567 bic r0, r0, #0xff0000
1568@ bic r0, r0, #0x008000
1569 ldr r1, [r1]
1570 mov r2, #0x110000
1571 orr r2, r2, #0x002200
1572 cmp r0, #0x2000
1573 bge m_s68k_read8_pcm_ram
1574 cmp r0, #0x20
1575 movlt r0, #0
1576 bxlt lr
1577 orr r2, r2, #(0x48+8) @ pcm.ch + addr_offset
1578 add r1, r1, r2
1579 and r2, r0, #0x1c
1580 ldr r1, [r1, r2, lsl #2]
1581 tst r0, #2
1582 moveq r0, r1, lsr #PCM_STEP_SHIFT
1583 movne r0, r1, lsr #(PCM_STEP_SHIFT+8)
1584 and r0, r0, #0xff
1585 bx lr
1586
1587m_s68k_read8_pcm_ram:
1588 orr r2, r2, #0x40
1589 ldr r2, [r1, r2]
1590 add r1, r1, #0x100000 @ pcm_ram
1591 and r2, r2, #0x0f000000 @ bank
1592 add r1, r1, r2, lsr #12
1593 bic r0, r0, #0x00e000
1594 mov r0, r0, lsr #1
1595 ldrb r0, [r1, r0]
1596 bx lr
1597
1598
1599m_s68k_read8_regs:
1600 bic r0, r0, #0xff0000
1601 bic r0, r0, #0x008000
1602 tst r0, #0x7e00
1603 movne r0, #0
1604 bxne lr
1605 sub r2, r0, #0x0e
1606 cmp r2, #(0x30-0x0e)
1607 blo m_s68k_read8_comm
1608 sub r2, r0, #0x58
1609 cmp r2, #0x10
1610 ldrlo r2, =gfx_cd_read
1611 ldrhs r2, =s68k_reg_read16
1612 stmfd sp!,{r0,lr}
1613 bic r0, r0, #1
1614 mov lr, pc
1615 bx r2
1616 ldmfd sp!,{r1,lr}
1617 tst r1, #1
1618 moveq r0, r0, lsr #8
1619 and r0, r0, #0xff
1620 bx lr
1621
1622m_s68k_read8_comm:
1623 ldr r1, =(Pico+0x22200)
1624 ldr r1, [r1]
1625 add r1, r1, #0x110000
1626 ldrb r1, [r1, r0]
1627 b s68k_poll_detect
1628
1629
1630@ @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
1631
1632
1633.macro m_s68k_read16_ram map_addr
1634 ldr r1, =(Pico+0x22200)
1635 bic r0, r0, #1
1636 ldr r1, [r1]
1637.if \map_addr
1638 add r0, r0, #\map_addr @ map to our address
1639.endif
1640 ldrh r0, [r1, r0]
1641 bx lr
1642.endm
1643
1644.macro m_s68k_read16_wordram_2M_decode map_addr
1645 ldr r2, =(Pico+0x22200)
1646 eor r0, r0, #2
1647 ldr r2, [r2]
1648 mov r0, r0, lsr #1 @ +4-6 <<16
1649 add r2, r2, #\map_addr @ map to our address
1650 ldrb r0, [r2, r0]
1651 orr r0, r0, r0, lsl #4
1652 bic r0, r0, #0xf0
1653 bx lr
1654.endm
1655
1656
1657m_s68k_read16_prg: @ 0x000000 - 0x07ffff
1658m_s68k_read16_wordram_2M: @ 0x080000 - 0x0bffff
1659m_s68k_read16_wordram_1M_b1: @ 0x0c0000 - 0x0dffff, maps to 0x0e0000
1660 m_s68k_read16_ram 0x020000
1661
1662
1663m_s68k_read16_wordram_2M_decode_b0: @ 0x080000 - 0x0bffff
1664 m_s68k_read16_wordram_2M_decode 0x080000
1665
1666
1667m_s68k_read16_wordram_2M_decode_b1: @ 0x080000 - 0x0bffff
1668 m_s68k_read16_wordram_2M_decode 0x0a0000
1669
1670
1671m_s68k_read16_wordram_1M_b0: @ 0x0c0000 - 0x0dffff (same as our offset :)
1672 m_s68k_read16_ram 0
1673
1674
1675@ m_s68k_read16_backup: @ 0xfe0000 - 0xfe3fff (repeated?)
1676@ bram is not meant to be accessed by words, does any game do this?
1677.equiv m_s68k_read16_backup, m_s68k_read8_backup
1678
1679
1680@ m_s68k_read16_pcm:
1681@ pcm is on 8-bit bus, would this be same as byte access?
1682.equiv m_s68k_read16_pcm, m_s68k_read8_pcm
1683
1684
1685m_s68k_read16_regs:
1686 bic r0, r0, #0xff0000
1687 bic r0, r0, #0x008000
1688 bic r0, r0, #0x000001
1689 tst r0, #0x7e00
1690 movne r0, #0
1691 bxne lr
1692 sub r2, r0, #0x58
1693 cmp r2, #0x10
1694 blo gfx_cd_read
1695 cmp r0, #8
1696 bne s68k_reg_read16
1697 mov r0, #1
1698 b Read_CDC_Host
1699
1700
1701@ @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
1702
1703
1704.macro m_s68k_read32_ram map_addr
1705 ldr r1, =(Pico+0x22200)
1706 bic r0, r0, #1
1707 ldr r1, [r1]
1708.if \map_addr
1709 add r0, r0, #\map_addr @ map to our address
1710.endif
1711 m_read32_gen
1712 bx lr
1713.endm
1714
1715.macro m_s68k_read32_wordram_2M_decode map_addr
1716 ldr r2, =(Pico+0x22200)
1717 eor r0, r0, #2
1718 ldr r2, [r2]
1719 mov r0, r0, lsr #1 @ +4-6 <<16
1720 add r2, r2, #\map_addr @ map to our address
1721 ldrb r1, [r2, r0]!
1722 tst r0, #1
1723 ldrneb r0, [r2, #-1]
1724 ldreqb r0, [r2, #2]
1725 orr r1, r1, r1, lsl #4
1726 bic r1, r1, #0xf0
1727 orr r0, r0, r0, lsl #4
1728 bic r0, r0, #0xf0
1729 orr r0, r0, r1, lsl #16
1730 bx lr
1731.endm
1732
1733
1734m_s68k_read32_prg: @ 0x000000 - 0x07ffff
1735m_s68k_read32_wordram_2M: @ 0x080000 - 0x0bffff
1736m_s68k_read32_wordram_1M_b1: @ 0x0c0000 - 0x0dffff, maps to 0x0e0000
1737 m_s68k_read32_ram 0x020000
1738
1739
1740m_s68k_read32_wordram_2M_decode_b0: @ 0x080000 - 0x0bffff
1741 m_s68k_read32_wordram_2M_decode 0x080000
1742
1743
1744m_s68k_read32_wordram_2M_decode_b1: @ 0x080000 - 0x0bffff
1745 m_s68k_read32_wordram_2M_decode 0x0a0000
1746
1747
1748m_s68k_read32_wordram_1M_b0: @ 0x0c0000 - 0x0dffff (same as our offset :)
1749 m_s68k_read32_ram 0
1750
1751
1752m_s68k_read32_backup: @ 0xfe0000 - 0xfe3fff (repeated?)
1753 @ bram is not meant to be accessed by words, does any game do this?
1754 mov r12,lr
1755 mov r3, r0
1756 bl m_s68k_read8_backup @ must preserve r3 and r12
1757 mov r1, r0
1758 add r0, r3, #2
1759 mov r3, r1
1760 bl m_s68k_read8_backup
1761 orr r0, r0, r3, lsl #16
1762 bx r12
1763
1764
1765m_s68k_read32_pcm:
1766 mov r12,lr
1767 mov r3, r0
1768 bl m_s68k_read8_pcm @ must preserve r3 and r12
1769 mov r1, r0
1770 add r0, r3, #2
1771 mov r3, r1
1772 bl m_s68k_read8_pcm
1773 orr r0, r0, r3, lsl #16
1774 bx r12
1775
1776
1777m_s68k_read32_regs:
1778 bic r0, r0, #0xff0000
1779 bic r0, r0, #0x008000
1780 bic r0, r0, #0x000001
1781 tst r0, #0x7e00
1782 movne r0, #0
1783 bxne lr
1784 sub r2, r0, #0x58
1785 cmp r2, #0x10
1786 add r1, r0, #2
1787 blo m_s68k_read32_regs_gfx
1788 stmfd sp!,{r1,lr}
1789 bl s68k_reg_read16
1790 swp r0, r0, [sp]
1791 bl s68k_reg_read16
1792 ldmfd sp!,{r1,lr}
1793 orr r0, r0, r1, lsl #16
1794 bx lr
1795
1796
1797m_s68k_read32_regs_gfx:
1798 stmfd sp!,{r1,lr}
1799 bl gfx_cd_read
1800 swp r0, r0, [sp]
1801 bl gfx_cd_read
1802 ldmfd sp!,{r1,lr}
1803 orr r0, r0, r1, lsl #16
1804 bx lr
1805
1806.pool
1807
1808@ @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
1809
1810
1811.macro m_s68k_write8_ram map_addr
1812 ldr r2, =(Pico+0x22200)
1813 eor r0, r0, #1
1814 ldr r2, [r2]
1815.if \map_addr
1816 add r0, r0, #\map_addr @ map to our address
1817.endif
1818 strb r1, [r2, r0]
1819 bx lr
1820.endm
1821
1822.macro m_s68k_write8_2M_decode map_addr
1823 ldr r2, =(Pico+0x22200)
1824 eor r0, r0, #2
1825 ldr r2, [r2]
1826 movs r0, r0, lsr #1 @ +4-6 <<16
1827 add r2, r2, #\map_addr @ map to our address
1828.endm
1829
1830.macro m_s68k_write8_2M_decode_m0 map_addr @ mode off
1831 m_s68k_write8_2M_decode \map_addr
1832 ldrb r0, [r2, r0]!
1833 and r1, r1, #0x0f
1834 movcc r1, r1, lsl #4
1835 andcc r3, r0, #0x0f
1836 andcs r3, r0, #0xf0
1837 orr r3, r3, r1
1838 cmp r0, r3 @ avoid writing if result is same
1839 strneb r3, [r2]
1840 bx lr
1841.endm
1842
1843.macro m_s68k_write8_2M_decode_m1 map_addr @ mode underwrite
1844 ands r1, r1, #0x0f
1845 bxeq lr
1846 m_s68k_write8_2M_decode \map_addr
1847 ldrb r0, [r2, r0]!
1848 movcc r1, r1, lsl #4
1849 andcc r3, r0, #0x0f
1850 andcs r3, r0, #0xf0
1851 tst r3, r3
1852 bxeq lr
1853 orr r3, r3, r1
1854 cmp r0, r3
1855 strneb r3, [r2]
1856 bx lr
1857.endm
1858
1859.macro m_s68k_write8_2M_decode_m2 map_addr @ mode overwrite
1860 ands r1, r1, #0x0f
1861 bxeq lr
1862 m_s68k_write8_2M_decode_m0 \map_addr @ same as in off mode
1863.endm
1864
1865
1866
1867m_s68k_write8_prg: @ 0x000000 - 0x07ffff
1868 ldr r2, =(Pico+0x22200)
1869 eor r0, r0, #1
1870 ldr r2, [r2]
1871 add r3, r0, #0x020000 @ map to our address
1872 add r12,r2, #0x110000
1873 ldr r12,[r12]
1874 and r12,r12,#0x00ff0000 @ wp
1875 cmp r0, r12, lsr #8
1876 strgeb r1, [r2, r3]
1877 bx lr
1878
1879
1880m_s68k_write8_wordram_2M: @ 0x080000 - 0x0bffff
1881m_s68k_write8_wordram_1M_b1: @ 0x0c0000 - 0x0dffff, maps to 0x0e0000
1882 m_s68k_write8_ram 0x020000
1883
1884
1885m_s68k_write8_2M_decode_b0_m0: @ 0x080000 - 0x0bffff
1886 m_s68k_write8_2M_decode_m0 0x080000
1887
1888m_s68k_write8_2M_decode_b0_m1:
1889 m_s68k_write8_2M_decode_m1 0x080000
1890
1891m_s68k_write8_2M_decode_b0_m2:
1892 m_s68k_write8_2M_decode_m2 0x080000
1893
1894m_s68k_write8_2M_decode_b1_m0:
1895 m_s68k_write8_2M_decode_m0 0x0a0000
1896
1897m_s68k_write8_2M_decode_b1_m1:
1898 m_s68k_write8_2M_decode_m1 0x0a0000
1899
1900m_s68k_write8_2M_decode_b1_m2:
1901 m_s68k_write8_2M_decode_m2 0x0a0000
1902
1903
1904m_s68k_write8_wordram_1M_b0: @ 0x0c0000 - 0x0dffff (same as our offset :)
1905 m_s68k_write8_ram 0
1906
1907
1908m_s68k_write8_backup: @ 0xfe0000 - 0xfe3fff (repeated?)
1909 @ must not trash r3 and r12
1910 ldr r2, =(Pico+0x22200)
1911 mov r0, r0, lsr #1
1912 ldr r2, [r2]
1913 bic r0, r0, #0xff0000
1914 bic r0, r0, #0x00e000
1915 add r2, r2, #0x110000
1916 add r2, r2, #0x000200
1917 strb r1, [r2, r0]
1918 ldr r1, =SRam
1919 mov r0, #1
1920 strb r0, [r1, #0x0e] @ SRam.changed = 1
1921 bx lr
1922
1923
1924m_s68k_write8_pcm:
1925 bic r0, r0, #0xff0000
1926 cmp r0, #0x12
1927 movlt r0, r0, lsr #1
1928 blt pcm_write
1929
1930 cmp r0, #0x2000
1931 bxlt lr
1932
1933m_s68k_write8_pcm_ram:
1934 ldr r3, =(Pico+0x22200)
1935 bic r0, r0, #0x00e000
1936 ldr r3, [r3]
1937 mov r0, r0, lsr #1
1938 add r2, r3, #0x110000
1939 add r2, r2, #0x002200
1940 add r2, r2, #0x000040
1941 ldr r2, [r2]
1942 add r3, r3, #0x100000 @ pcm_ram
1943 and r2, r2, #0x0f000000 @ bank
1944 add r3, r3, r2, lsr #12
1945 strb r1, [r3, r0]
1946 bx lr
1947
1948
1949m_s68k_write8_regs:
1950 bic r0, r0, #0xff0000
1951 bic r0, r0, #0x008000
1952 tst r0, #0x7e00
1953 movne r0, #0
1954 bxne lr
1955 sub r2, r0, #0x58
1956 cmp r2, #0x10
1957 bhs s68k_reg_write8
1958 bic r0, r0, #1
1959 orr r1, r1, r1, lsl #8
1960 b gfx_cd_write16
1961
1962
1963@ @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
1964
1965
1966.macro m_s68k_write16_ram map_addr
1967 ldr r2, =(Pico+0x22200)
1968 bic r0, r0, #1
1969 ldr r2, [r2]
1970.if \map_addr
1971 add r0, r0, #\map_addr @ map to our address
1972.endif
1973 strh r1, [r2, r0]
1974 bx lr
1975.endm
1976
1977.macro m_s68k_write16_2M_decode map_addr
1978 ldr r2, =(Pico+0x22200)
1979 eor r0, r0, #2
1980 ldr r2, [r2]
1981 mov r0, r0, lsr #1 @ +4-6 <<16
1982 add r2, r2, #\map_addr @ map to our address
1983.endm
1984
1985.macro m_s68k_write16_2M_decode_m0 map_addr @ mode off
1986 m_s68k_write16_2M_decode \map_addr
1987 bic r1, r1, #0xf0
1988 orr r1, r1, r1, lsr #4
1989 strb r1, [r2, r0]
1990 bx lr
1991.endm
1992
1993.macro m_s68k_write16_2M_decode_m1 map_addr @ mode underwrite
1994 bics r1, r1, #0xf000
1995 bicnes r1, r1, #0x00f0
1996 bxeq lr
1997 orr r1, r1, r1, lsr #4
1998 m_s68k_write16_2M_decode \map_addr
1999 ldrb r0, [r2, r0]!
2000 and r3, r1, #0x0f
2001 and r1, r1, #0xf0
2002 tst r0, #0x0f
2003 orreq r0, r0, r3
2004 tst r0, #0xf0
2005 orreq r0, r0, r1
2006 strb r0, [r2]
2007 bx lr
2008.endm
2009
2010.macro m_s68k_write16_2M_decode_m2 map_addr @ mode overwrite
2011 bics r1, r1, #0xf000
2012 bicnes r1, r1, #0x00f0
2013 bxeq lr
2014 orr r1, r1, r1, lsr #4
2015 m_s68k_write16_2M_decode \map_addr
2016 ldrb r0, [r2, r0]!
2017 ands r3, r1, #0x0f
2018 andne r0, r0, #0xf0
2019 orrne r0, r0, r3
2020 ands r1, r1, #0xf0
2021 andne r0, r0, #0x0f
2022 orrne r0, r0, r1
2023 strb r0, [r2]
2024 bx lr
2025.endm
2026
2027
2028
2029m_s68k_write16_prg: @ 0x000000 - 0x07ffff
2030 ldr r2, =(Pico+0x22200)
2031 bic r0, r0, #1
2032 ldr r2, [r2]
2033 add r3, r0, #0x020000 @ map to our address
2034 add r12,r2, #0x110000
2035 ldr r12,[r12]
2036 and r12,r12,#0x00ff0000 @ wp
2037 cmp r0, r12, lsr #8
2038 strgeh r1, [r2, r3]
2039 bx lr
2040
2041
2042m_s68k_write16_wordram_2M: @ 0x080000 - 0x0bffff
2043m_s68k_write16_wordram_1M_b1: @ 0x0c0000 - 0x0dffff, maps to 0x0e0000
2044 m_s68k_write16_ram 0x020000
2045
2046
2047m_s68k_write16_2M_decode_b0_m0: @ 0x080000 - 0x0bffff
2048 m_s68k_write16_2M_decode_m0 0x080000
2049
2050m_s68k_write16_2M_decode_b0_m1:
2051 m_s68k_write16_2M_decode_m1 0x080000
2052
2053m_s68k_write16_2M_decode_b0_m2:
2054 m_s68k_write16_2M_decode_m2 0x080000
2055
2056m_s68k_write16_2M_decode_b1_m0:
2057 m_s68k_write16_2M_decode_m0 0x0a0000
2058
2059m_s68k_write16_2M_decode_b1_m1:
2060 m_s68k_write16_2M_decode_m1 0x0a0000
2061
2062m_s68k_write16_2M_decode_b1_m2:
2063 m_s68k_write16_2M_decode_m2 0x0a0000
2064
2065
2066m_s68k_write16_wordram_1M_b0: @ 0x0c0000 - 0x0dffff (same as our offset :)
2067 m_s68k_write16_ram 0
2068
2069
2070@ m_s68k_write16_backup:
2071.equiv m_s68k_write16_backup, m_s68k_write8_backup
2072
2073
2074@ m_s68k_write16_pcm:
2075.equiv m_s68k_write16_pcm, m_s68k_write8_pcm
2076
2077
2078m_s68k_write16_regs:
2079 bic r0, r0, #0xff0000
2080 bic r0, r0, #0x008000
2081 bic r0, r0, #1
2082 tst r0, #0x7e00
2083 movne r0, #0
2084 bxne lr
2085 cmp r0, #0x0e
2086 beq m_s68k_write16_regs_spec
2087 sub r2, r0, #0x58
2088 cmp r2, #0x10
2089 blo gfx_cd_write16
2090 and r3, r1, #0xff
2091 add r2, r0, #1
2092 stmfd sp!,{r2,r3,lr}
2093 mov r1, r1, lsr #8
2094 bl s68k_reg_write8
2095 ldmfd sp!,{r0,r1,lr}
2096 b s68k_reg_write8
2097
2098m_s68k_write16_regs_spec: @ special case
2099 ldr r2, =(Pico+0x22200)
2100 mov r0, #0x110000
2101 ldr r2, [r2]
2102 add r0, r0, #0x00000f
2103 strb r1, [r2, r0] @ if (a == 0xe) s68k_regs[0xf] = d;
2104 bx lr
2105
2106
2107@ @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
2108
2109
2110.macro m_s68k_write32_ram map_addr
2111 ldr r2, =(Pico+0x22200)
2112 bic r0, r0, #1
2113 ldr r2, [r2]
2114.if \map_addr
2115 add r0, r0, #\map_addr @ map to our address
2116.endif
2117 m_write32_gen
2118 bx lr
2119.endm
2120
2121.macro m_s68k_write32_2M_decode map_addr
2122 ldr r2, =(Pico+0x22200)
2123 eor r0, r0, #2
2124 ldr r2, [r2]
2125 mov r0, r0, lsr #1 @ +4-6 <<16
2126 add r2, r2, #\map_addr @ map to our address
2127.endm
2128
2129.macro m_s68k_write32_2M_decode_m0 map_addr @ mode off
2130 m_s68k_write32_2M_decode \map_addr
2131 bic r1, r1, #0x000000f0
2132 bic r1, r1, #0x00f00000
2133 orr r1, r1, r1, lsr #4
2134 mov r3, r1, lsr #16
2135 strb r3, [r2, r0]!
2136 tst r0, #1
2137 strneb r1, [r2, #-1]
2138 streqb r1, [r2, #3]
2139 bx lr
2140.endm
2141
2142.macro m_s68k_write32_2M_decode_m1 map_addr @ mode underwrite
2143 bics r1, r1, #0x000000f0
2144 bicnes r1, r1, #0x0000f000
2145 bicnes r1, r1, #0x00f00000
2146 bicnes r1, r1, #0xf0000000
2147 bxeq lr
2148 orr r1, r1, r1, lsr #4
2149 m_s68k_write32_2M_decode \map_addr
2150 ldrb r3, [r2, r0]!
2151 tst r0, #1
2152 ldrneb r0, [r2, #-1]
2153 ldreqb r0, [r2, #3]
2154 and r12,r1, #0x0000000f
2155 orr r0, r0, r3, lsl #16
2156 orrne r0, r0, #0x80000000 @ remember addr lsb bit
2157 tst r0, #0x0000000f
2158 orreq r0, r0, r12
2159 tst r0, #0x000000f0
2160 andeq r12,r1, #0x000000f0
2161 orreq r0, r0, r12
2162 tst r0, #0x000f0000
2163 andeq r12,r1, #0x000f0000
2164 orreq r0, r0, r12
2165 tst r0, #0x00f00000
2166 andeq r12,r1, #0x00f00000
2167 orreq r0, r0, r12
2168 tst r0, #0x80000000
2169 strneb r0, [r2, #-1]
2170 streqb r0, [r2, #3]
2171 mov r0, r0, lsr #16
2172 strb r0, [r2]
2173 bx lr
2174.endm
2175
2176.macro m_s68k_write32_2M_decode_m2 map_addr @ mode overwrite
2177 bics r1, r1, #0x000000f0
2178 bicnes r1, r1, #0x0000f000
2179 bicnes r1, r1, #0x00f00000
2180 bicnes r1, r1, #0xf0000000
2181 bxeq lr
2182 orr r1, r1, r1, lsr #4
2183 m_s68k_write32_2M_decode \map_addr
2184 ldrb r3, [r2, r0]!
2185 tst r0, #1
2186 ldrneb r0, [r2, #-1]
2187 ldreqb r0, [r2, #3]
2188 orrne r1, r1, #0x80000000 @ remember addr lsb bit
2189 orr r0, r0, r3, lsl #16
2190 tst r1, #0x0000000f
2191 andeq r12,r0, #0x0000000f
2192 orreq r1, r1, r12
2193 tst r1, #0x000000f0
2194 andeq r12,r0, #0x000000f0
2195 orreq r1, r1, r12
2196 tst r1, #0x000f0000
2197 andeq r12,r0, #0x000f0000
2198 orreq r1, r1, r12
2199 tst r1, #0x00f00000
2200 andeq r12,r0, #0x00f00000
2201 orreq r1, r1, r12
2202 cmp r0, r1
2203 bxeq lr
2204 tst r1, #0x80000000
2205 strneb r1, [r2, #-1]
2206 streqb r1, [r2, #3]
2207 mov r1, r1, lsr #16
2208 strb r1, [r2]
2209 bx lr
2210.endm
2211
2212
2213
2214m_s68k_write32_prg: @ 0x000000 - 0x07ffff
2215 ldr r2, =(Pico+0x22200)
2216 bic r0, r0, #1
2217 ldr r2, [r2]
2218 add r3, r0, #0x020000 @ map to our address
2219 add r12,r2, #0x110000
2220 ldr r12,[r12]
2221 and r12,r12,#0x00ff0000 @ wp
2222 cmp r0, r12, lsr #8
2223 bxlt lr
2224 mov r0, r1, lsr #16
2225 strh r0, [r2, r3]!
2226 strh r1, [r2, #2]
2227 bx lr
2228
2229
2230m_s68k_write32_wordram_2M: @ 0x080000 - 0x0bffff
2231m_s68k_write32_wordram_1M_b1: @ 0x0c0000 - 0x0dffff, maps to 0x0e0000
2232 m_s68k_write32_ram 0x020000
2233
2234
2235m_s68k_write32_2M_decode_b0_m0: @ 0x080000 - 0x0bffff
2236 m_s68k_write32_2M_decode_m0 0x080000
2237
2238m_s68k_write32_2M_decode_b0_m1:
2239 m_s68k_write32_2M_decode_m1 0x080000
2240
2241m_s68k_write32_2M_decode_b0_m2:
2242 m_s68k_write32_2M_decode_m2 0x080000
2243
2244m_s68k_write32_2M_decode_b1_m0:
2245 m_s68k_write32_2M_decode_m0 0x0a0000
2246
2247m_s68k_write32_2M_decode_b1_m1:
2248 m_s68k_write32_2M_decode_m1 0x0a0000
2249
2250m_s68k_write32_2M_decode_b1_m2:
2251 m_s68k_write32_2M_decode_m2 0x0a0000
2252
2253
2254m_s68k_write32_wordram_1M_b0: @ 0x0c0000 - 0x0dffff (same as our offset :)
2255 m_s68k_write32_ram 0
2256
2257
2258m_s68k_write32_backup:
2259 add r12,r0, #2
2260 mov r3, r1
2261 mov r1, r1, lsr #16
2262 stmfd sp!,{lr}
2263 bl m_s68k_write8_backup @ must preserve r3 and r12
2264 ldmfd sp!,{lr}
2265 mov r0, r12
2266 mov r1, r3
2267 b m_s68k_write8_backup
2268
2269
2270m_s68k_write32_pcm:
2271 bic r0, r0, #0xff0000
2272 cmp r0, #0x12
2273 blt m_s68k_write32_pcm_reg
2274
2275 cmp r0, #0x2000
2276 bxlt lr
2277
2278m_s68k_write32_pcm_ram:
2279 ldr r3, =(Pico+0x22200)
2280 bic r0, r0, #0x00e000
2281 ldr r3, [r3]
2282 mov r0, r0, lsr #1
2283 add r2, r3, #0x110000
2284 add r2, r2, #0x002200
2285 add r2, r2, #0x000040
2286 ldr r2, [r2]
2287 add r3, r3, #0x100000 @ pcm_ram
2288 and r2, r2, #0x0f000000 @ bank
2289 add r3, r3, r2, lsr #12
2290 mov r1, r1, ror #16
2291 strb r1, [r3, r0]!
2292 mov r1, r1, ror #16
2293 strb r1, [r3]
2294 bx lr
2295
2296m_s68k_write32_pcm_reg:
2297 mov r0, r0, lsr #1
2298 stmfd sp!,{r0,r1,lr}
2299 mov r1, r1, lsr #16
2300 bl pcm_write
2301 ldmfd sp!,{r0,r1,lr}
2302 add r0, r0, #1
2303 b pcm_write
2304
2305
2306m_s68k_write32_regs:
2307 bic r0, r0, #0xff0000
2308 bic r0, r0, #0x008000
2309 bic r0, r0, #1
2310 tst r0, #0x7e00
2311 bxne lr
2312 sub r2, r0, #0x58
2313 cmp r2, #0x10
2314 blo m_s68k_write32_regs_gfx
2315 and r2, r0, #0x1fc
2316 cmp r2, #0x0c
2317 beq m_s68k_write32_regs_spec @ hits 0x0f
2318 and r2, r0, #0x1f0
2319 cmp r2, #0x20
2320 beq m_s68k_write32_regs_comm
2321
2322 stmfd sp!,{r0,r1,lr}
2323 mov r1, r1, lsr #24
2324 bl s68k_reg_write8
2325 ldr r0, [sp]
2326 ldr r1, [sp, #4]
2327 add r0, r0, #1
2328 mov r1, r1, lsr #16
2329 bl s68k_reg_write8
2330 ldr r0, [sp]
2331 ldr r1, [sp, #4]
2332 add r0, r0, #2
2333 mov r1, r1, lsr #8
2334 bl s68k_reg_write8
2335 ldmfd sp!,{r0,r1,lr}
2336 add r0, r0, #3
2337 b s68k_reg_write8
2338
2339m_s68k_write32_regs_gfx:
2340 stmfd sp!,{r0,r1,lr}
2341 mov r1, r1, lsr #16
2342 bl gfx_cd_write16
2343 ldmfd sp!,{r0,r1,lr}
2344 add r0, r0, #2
2345 b gfx_cd_write16
2346
2347m_s68k_write32_regs_comm: @ Handle the 0x20-0x2f range
2348 ldr r2, =(Pico+0x22200)
2349 mov r3, #0xff
2350 ldr r2, [r2]
2351 orr r3, r3, r3, lsl #16
2352 add r2, r2, #0x110000
2353 and r12,r3, r1, ror #16 @ data is big-endian to be written as little, have to byteswap
2354 and r1, r3, r1, ror #24
2355 orr r1, r1, r12,lsl #8 @ end of byteswap
2356 cmp r0, #0x2e
2357 strh r1, [r0, r2]!
2358 movne r1, r1, lsr #16
2359 strneh r1, [r0, #2]
2360 bx lr
2361
2362m_s68k_write32_regs_spec:
2363 stmfd sp!,{r0,r1,lr}
2364 mov r1, r1, lsr #16
2365 bl m_s68k_write16_regs
2366 ldmfd sp!,{r0,r1,lr}
2367 add r0, r0, #2
2368 b m_s68k_write16_regs
2369
2370
fast MegaDrive/MegaCD/32X emulator