be2c4208 |
1 | #include "../pico_int.h" |
2 | #include "../memory.h" |
3 | |
4 | static const char str_mars[] = "MARS"; |
5 | |
6 | struct Pico32xMem { |
7 | u8 sdram[0x40000]; |
8 | u8 dram[0x40000]; // AKA fb |
9 | u8 m68k_rom[M68K_BANK_SIZE]; // 0x100 |
10 | }; |
11 | |
12 | static struct Pico32xMem *Pico32xMem; |
13 | |
14 | static u32 p32x_reg_read16(u32 a) |
15 | { |
16 | a &= 0x3e; |
17 | |
18 | return Pico32x.regs[a / 2]; |
19 | } |
20 | |
21 | static void p32x_reg_write16(u32 a, u32 d) |
22 | { |
23 | a &= 0x3e; |
24 | |
25 | if (a == 0 && !(Pico32x.regs[0] & 1)) { |
26 | Pico32x.regs[0] |= 1; |
27 | Pico32xStartup(); |
28 | return; |
29 | } |
30 | } |
31 | |
32 | static void p32x_reg_write8(u32 a, u32 d) |
33 | { |
34 | a &= 0x3f; |
35 | |
36 | if (a == 1 && !(Pico32x.regs[0] & 1)) { |
37 | Pico32x.regs[0] |= 1; |
38 | Pico32xStartup(); |
39 | return; |
40 | } |
41 | } |
42 | |
43 | // VDP regs |
44 | static u32 p32x_vdp_read16(u32 a) |
45 | { |
46 | a &= 0x0e; |
47 | |
48 | return Pico32x.vdp_regs[a / 2]; |
49 | } |
50 | |
51 | static void p32x_vdp_write16(u32 a, u32 d) |
52 | { |
53 | a &= 0x0e; |
54 | |
55 | switch (a) { |
56 | case 0x0a: |
57 | Pico32x.pending_fb = d & 1; |
58 | if (Pico.video.status & 8) { |
59 | Pico32x.vdp_regs[0x0a/2] &= ~1; |
60 | Pico32x.vdp_regs[0x0a/2] |= d & 1; |
61 | } |
62 | break; |
63 | } |
64 | } |
65 | |
66 | static void p32x_vdp_write8(u32 a, u32 d) |
67 | { |
68 | a &= 0x0f; |
69 | |
70 | switch (a) { |
71 | case 0x0b: |
72 | Pico32x.pending_fb = d & 1; |
73 | if (Pico.video.status & 8) { |
74 | Pico32x.vdp_regs[0x0a/2] &= ~1; |
75 | Pico32x.vdp_regs[0x0a/2] |= d & 1; |
76 | } |
77 | break; |
78 | } |
79 | } |
80 | |
81 | // default 32x handlers |
82 | u32 PicoRead8_32x(u32 a) |
83 | { |
84 | u32 d = 0; |
85 | if ((a & 0xffc0) == 0x5100) { // a15100 |
86 | d = p32x_reg_read16(a); |
87 | goto out_16to8; |
88 | } |
89 | |
90 | if ((a & 0xfff0) == 0x5180 && (Pico32x.regs[0] & 1)) { |
91 | d = p32x_vdp_read16(a); |
92 | goto out_16to8; |
93 | } |
94 | |
95 | if ((a & 0xfffc) == 0x30ec) { // a130ec |
96 | d = str_mars[a & 3]; |
97 | goto out; |
98 | } |
99 | |
100 | elprintf(EL_UIO, "m68k unmapped r8 [%06x] @%06x", a, SekPc); |
101 | return d; |
102 | |
103 | out_16to8: |
104 | if (a & 1) |
105 | d &= 0xff; |
106 | else |
107 | d >>= 8; |
108 | |
109 | out: |
110 | elprintf(EL_32X, "m68k 32x r8 [%06x] %02x @%06x", a, d, SekPc); |
111 | return d; |
112 | } |
113 | |
114 | u32 PicoRead16_32x(u32 a) |
115 | { |
116 | u32 d = 0; |
117 | if ((a & 0xffc0) == 0x5100) { // a15100 |
118 | d = p32x_reg_read16(a); |
119 | goto out; |
120 | } |
121 | |
122 | if ((a & 0xfff0) == 0x5180 && (Pico32x.regs[0] & 1)) { // a15180 |
123 | d = p32x_vdp_read16(a); |
124 | goto out; |
125 | } |
126 | |
127 | if ((a & 0xfffc) == 0x30ec) { // a130ec |
128 | d = !(a & 2) ? ('M'<<8)|'A' : ('R'<<8)|'S'; |
129 | goto out; |
130 | } |
131 | |
132 | elprintf(EL_UIO, "m68k unmapped r16 [%06x] @%06x", a, SekPc); |
133 | return d; |
134 | |
135 | out: |
136 | elprintf(EL_32X, "m68k 32x r16 [%06x] %04x @%06x", a, d, SekPc); |
137 | return d; |
138 | } |
139 | |
140 | void PicoWrite8_32x(u32 a, u32 d) |
141 | { |
142 | if ((a & 0xfc00) == 0x5000) |
143 | elprintf(EL_32X, "m68k 32x w8 [%06x] %02x @%06x", a, d & 0xff, SekPc); |
144 | |
145 | if ((a & 0xffc0) == 0x5100) { // a15100 |
146 | p32x_reg_write8(a, d); |
147 | return; |
148 | } |
149 | |
150 | if ((a & 0xfff0) == 0x5180 && (Pico32x.regs[0] & 1)) { // a15180 |
151 | p32x_vdp_write8(a, d); |
152 | return; |
153 | } |
154 | |
155 | elprintf(EL_UIO, "m68k unmapped w8 [%06x] %02x @%06x", a, d & 0xff, SekPc); |
156 | } |
157 | |
158 | void PicoWrite16_32x(u32 a, u32 d) |
159 | { |
160 | if ((a & 0xfc00) == 0x5000) |
161 | elprintf(EL_UIO, "m68k 32x w16 [%06x] %04x @%06x", a, d & 0xffff, SekPc); |
162 | |
163 | if ((a & 0xffc0) == 0x5100) { // a15100 |
164 | p32x_reg_write16(a, d); |
165 | return; |
166 | } |
167 | |
168 | if ((a & 0xfff0) == 0x5180 && (Pico32x.regs[0] & 1)) { // a15180 |
169 | p32x_vdp_write16(a, d); |
170 | return; |
171 | } |
172 | |
173 | elprintf(EL_UIO, "m68k unmapped w16 [%06x] %04x @%06x", a, d & 0xffff, SekPc); |
174 | } |
175 | |
176 | // hint vector is writeable |
177 | static void PicoWrite8_hint(u32 a, u32 d) |
178 | { |
179 | if ((a & 0xfffc) == 0x0070) { |
180 | Pico32xMem->m68k_rom[a ^ 1] = d; |
181 | return; |
182 | } |
183 | |
184 | elprintf(EL_UIO, "m68k unmapped w8 [%06x] %02x @%06x", a, d & 0xff, SekPc); |
185 | } |
186 | |
187 | static void PicoWrite16_hint(u32 a, u32 d) |
188 | { |
189 | if ((a & 0xfffc) == 0x0070) { |
190 | ((u16 *)Pico32xMem->m68k_rom)[a/2] = d; |
191 | return; |
192 | } |
193 | |
194 | elprintf(EL_UIO, "m68k unmapped w16 [%06x] %04x @%06x", a, d & 0xffff, SekPc); |
195 | } |
196 | |
197 | #define HWSWAP(x) (((x) << 16) | ((x) >> 16)) |
198 | void PicoMemSetup32x(void) |
199 | { |
200 | unsigned short *ps; |
201 | unsigned int *pl; |
202 | unsigned int rs, rs1; |
203 | int i; |
204 | |
205 | Pico32xMem = calloc(1, sizeof(*Pico32xMem)); |
206 | if (Pico32xMem == NULL) { |
207 | elprintf(EL_STATUS, "OOM"); |
208 | return; |
209 | } |
210 | |
211 | // generate 68k ROM |
212 | ps = (unsigned short *)Pico32xMem->m68k_rom; |
213 | pl = (unsigned int *)Pico32xMem->m68k_rom; |
214 | for (i = 1; i < 0xc0/4; i++) |
215 | pl[i] = HWSWAP(0x880200 + i * 6); |
216 | |
217 | // fill with nops |
218 | for (i = 0xc0/2; i < 0x100/2; i++) |
219 | ps[i] = 0x4e71; |
220 | |
221 | ps[0xc0/2] = 0x46fc; |
222 | ps[0xc2/2] = 0x2700; // move #0x2700,sr |
223 | ps[0xfe/2] = 0x60fe; // jump to self |
224 | |
225 | // fill remaining mem with ROM |
226 | memcpy(Pico32xMem->m68k_rom + 0x100, Pico.rom + 0x100, M68K_BANK_SIZE - 0x100); |
227 | |
228 | // cartridge area becomes unmapped |
229 | // XXX: we take the easy way and don't unmap ROM, |
230 | // so that we can avoid handling the RV bit. |
231 | // m68k_map_unmap(0x000000, 0x3fffff); |
232 | |
233 | // MD ROM area |
234 | cpu68k_map_set(m68k_read8_map, 0x000000, M68K_BANK_SIZE - 1, Pico32xMem->m68k_rom, 0); |
235 | cpu68k_map_set(m68k_read16_map, 0x000000, M68K_BANK_SIZE - 1, Pico32xMem->m68k_rom, 0); |
236 | cpu68k_map_set(m68k_write8_map, 0x000000, M68K_BANK_SIZE - 1, PicoWrite8_hint, 1); // TODO verify |
237 | cpu68k_map_set(m68k_write16_map, 0x000000, M68K_BANK_SIZE - 1, PicoWrite16_hint, 1); |
238 | |
239 | // 32X ROM (unbanked, XXX: consider mirroring?) |
240 | rs1 = rs = (Pico.romsize + M68K_BANK_MASK) & ~M68K_BANK_MASK; |
241 | if (rs1 > 0x80000) |
242 | rs1 = 0x80000; |
243 | cpu68k_map_set(m68k_read8_map, 0x880000, 0x880000 + rs1 - 1, Pico.rom, 0); |
244 | cpu68k_map_set(m68k_read16_map, 0x880000, 0x880000 + rs1 - 1, Pico.rom, 0); |
245 | |
246 | // 32X ROM (banked) |
247 | if (rs > 0x100000) |
248 | rs = 0x100000; |
249 | cpu68k_map_set(m68k_read8_map, 0x900000, 0x900000 + rs - 1, Pico.rom, 0); |
250 | cpu68k_map_set(m68k_read16_map, 0x900000, 0x900000 + rs - 1, Pico.rom, 0); |
251 | } |
252 | |