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comparison z80_util.c @ 1769:8fe162bdb038 mame_interp

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Merge from default
author Michael Pavone <pavone@retrodev.com>
date Fri, 01 Mar 2019 14:17:29 -0800
parents 6e4faa10f9ee
children 72540af9c90a
comparison
equal deleted inserted replaced
1768:63256371046f 1769:8fe162bdb038
1 #include <string.h>
2
3 void z80_read_8(z80_context *context)
4 {
5 context->cycles += 3 * context->opts->gen.clock_divider;
6 uint8_t *fast = context->fastread[context->scratch1 >> 10];
7 if (fast) {
8 context->scratch1 = fast[context->scratch1 & 0x3FF];
9 } else {
10 context->scratch1 = read_byte(context->scratch1, (void **)context->mem_pointers, &context->opts->gen, context);
11 }
12 }
13
14 void z80_write_8(z80_context *context)
15 {
16 context->cycles += 3 * context->opts->gen.clock_divider;
17 uint8_t *fast = context->fastwrite[context->scratch2 >> 10];
18 if (fast) {
19 fast[context->scratch2 & 0x3FF] = context->scratch1;
20 } else {
21 write_byte(context->scratch2, context->scratch1, (void **)context->mem_pointers, &context->opts->gen, context);
22 }
23 }
24
25 void z80_io_read8(z80_context *context)
26 {
27 uint32_t tmp_mask = context->opts->gen.address_mask;
28 memmap_chunk const *tmp_map = context->opts->gen.memmap;
29 uint32_t tmp_chunks = context->opts->gen.memmap_chunks;
30
31 context->opts->gen.address_mask = context->io_mask;
32 context->opts->gen.memmap = context->io_map;
33 context->opts->gen.memmap_chunks = context->io_chunks;
34
35 context->cycles += 4 * context->opts->gen.clock_divider;
36 context->scratch1 = read_byte(context->scratch1, (void **)context->mem_pointers, &context->opts->gen, context);
37
38 context->opts->gen.address_mask = tmp_mask;
39 context->opts->gen.memmap = tmp_map;
40 context->opts->gen.memmap_chunks = tmp_chunks;
41 }
42
43 void z80_io_write8(z80_context *context)
44 {
45 uint32_t tmp_mask = context->opts->gen.address_mask;
46 memmap_chunk const *tmp_map = context->opts->gen.memmap;
47 uint32_t tmp_chunks = context->opts->gen.memmap_chunks;
48
49 context->opts->gen.address_mask = context->io_mask;
50 context->opts->gen.memmap = context->io_map;
51 context->opts->gen.memmap_chunks = context->io_chunks;
52
53 context->cycles += 4 * context->opts->gen.clock_divider;
54 write_byte(context->scratch2, context->scratch1, (void **)context->mem_pointers, &context->opts->gen, context);
55
56 context->opts->gen.address_mask = tmp_mask;
57 context->opts->gen.memmap = tmp_map;
58 context->opts->gen.memmap_chunks = tmp_chunks;
59 }
60
61 //quick hack until I get a chance to change which init method these get passed to
62 static memmap_chunk const * tmp_io_chunks;
63 static uint32_t tmp_num_io_chunks, tmp_io_mask;
64 void init_z80_opts(z80_options * options, memmap_chunk const * chunks, uint32_t num_chunks, memmap_chunk const * io_chunks, uint32_t num_io_chunks, uint32_t clock_divider, uint32_t io_address_mask)
65 {
66 memset(options, 0, sizeof(*options));
67 options->gen.memmap = chunks;
68 options->gen.memmap_chunks = num_chunks;
69 options->gen.address_mask = 0xFFFF;
70 options->gen.max_address = 0xFFFF;
71 options->gen.clock_divider = clock_divider;
72 tmp_io_chunks = io_chunks;
73 tmp_num_io_chunks = num_io_chunks;
74 tmp_io_mask = io_address_mask;
75 }
76
77 void z80_options_free(z80_options *opts)
78 {
79 free(opts);
80 }
81
82 z80_context * init_z80_context(z80_options *options)
83 {
84 z80_context *context = calloc(1, sizeof(z80_context));
85 context->opts = options;
86 context->io_map = (memmap_chunk *)tmp_io_chunks;
87 context->io_chunks = tmp_num_io_chunks;
88 context->io_mask = tmp_io_mask;
89 context->int_cycle = context->int_end_cycle = context->nmi_cycle = 0xFFFFFFFFU;
90 z80_invalidate_code_range(context, 0, 0xFFFF);
91 return context;
92 }
93
94 void z80_sync_cycle(z80_context *context, uint32_t target_cycle)
95 {
96 if (context->iff1 && context->int_cycle < target_cycle) {
97 if (context->cycles > context->int_end_cycle) {
98 context->int_cycle = 0xFFFFFFFFU;
99 } else {
100 target_cycle = context->int_cycle;
101 }
102 };
103 if (context->nmi_cycle < target_cycle) {
104 target_cycle = context->nmi_cycle;
105 }
106 context->sync_cycle = target_cycle;
107 }
108
109 void z80_run(z80_context *context, uint32_t target_cycle)
110 {
111 if (context->reset || context->busack) {
112 context->cycles = target_cycle;
113 } else if (target_cycle > context->cycles) {
114 if (context->busreq) {
115 //busreq is sampled at the end of an m-cycle
116 //we can approximate that by running for a single m-cycle after a bus request
117 target_cycle = context->cycles + 4 * context->opts->gen.clock_divider;
118 }
119 z80_execute(context, target_cycle);
120 if (context->busreq) {
121 context->busack = 1;
122 }
123 }
124 }
125
126 void z80_assert_reset(z80_context * context, uint32_t cycle)
127 {
128 z80_run(context, cycle);
129 context->reset = 1;
130 }
131
132 void z80_clear_reset(z80_context * context, uint32_t cycle)
133 {
134 z80_run(context, cycle);
135 if (context->reset) {
136 context->imode = 0;
137 context->iff1 = context->iff2 = 0;
138 context->pc = 0;
139 context->reset = 0;
140 if (context->busreq) {
141 //TODO: Figure out appropriate delay
142 context->busack = 1;
143 }
144 }
145 }
146
147 #define MAX_MCYCLE_LENGTH 6
148 void z80_assert_busreq(z80_context * context, uint32_t cycle)
149 {
150 z80_run(context, cycle);
151 context->busreq = 1;
152 //this is an imperfect aproximation since most M-cycles take less tstates than the max
153 //and a short 3-tstate m-cycle can take an unbounded number due to wait states
154 if (context->cycles - cycle > MAX_MCYCLE_LENGTH * context->opts->gen.clock_divider) {
155 context->busack = 1;
156 }
157 }
158
159 void z80_clear_busreq(z80_context * context, uint32_t cycle)
160 {
161 z80_run(context, cycle);
162 context->busreq = 0;
163 context->busack = 0;
164 //there appears to be at least a 1 Z80 cycle delay between busreq
165 //being released and resumption of execution
166 context->cycles += context->opts->gen.clock_divider;
167 }
168
169 void z80_assert_nmi(z80_context *context, uint32_t cycle)
170 {
171 context->nmi_cycle = cycle;
172 }
173
174 uint8_t z80_get_busack(z80_context * context, uint32_t cycle)
175 {
176 z80_run(context, cycle);
177 return context->busack;
178 }
179
180 void z80_invalidate_code_range(z80_context *context, uint32_t startA, uint32_t endA)
181 {
182 for(startA &= ~0x3FF; startA < endA; startA += 1024)
183 {
184 uint8_t *start = get_native_pointer(startA, (void**)context->mem_pointers, &context->opts->gen);
185 if (start) {
186 uint8_t *end = get_native_pointer(startA + 1023, (void**)context->mem_pointers, &context->opts->gen);
187 if (!end || end - start != 1023) {
188 start = NULL;
189 }
190 }
191 context->fastread[startA >> 10] = start;
192 start = get_native_write_pointer(startA, (void**)context->mem_pointers, &context->opts->gen);
193 if (start) {
194 uint8_t *end = get_native_write_pointer(startA + 1023, (void**)context->mem_pointers, &context->opts->gen);
195 if (!end || end - start != 1023) {
196 start = NULL;
197 }
198 }
199 context->fastwrite[startA >> 10] = start;
200 }
201 }
202
203 void z80_adjust_cycles(z80_context * context, uint32_t deduction)
204 {
205 context->cycles -= deduction;
206 if (context->int_cycle != 0xFFFFFFFFU) {
207 if (context->int_cycle > deduction) {
208 context->int_cycle -= deduction;
209 } else {
210 context->int_cycle = 0;
211 }
212 }
213 if (context->int_end_cycle != 0xFFFFFFFFU) {
214 if (context->int_end_cycle > deduction) {
215 context->int_end_cycle -= deduction;
216 } else {
217 context->int_end_cycle = 0;
218 }
219 }
220 if (context->nmi_cycle != 0xFFFFFFFFU) {
221 if (context->nmi_cycle > deduction) {
222 context->nmi_cycle -= deduction;
223 } else {
224 context->nmi_cycle = 0;
225 }
226 }
227 }
228
229 void z80_serialize(z80_context *context, serialize_buffer *buf)
230 {
231 //TODO: Implement me
232 }
233
234 void z80_deserialize(deserialize_buffer *buf, void *vcontext)
235 {
236 //TODO: Implement me
237 }
238
239 void zinsert_breakpoint(z80_context * context, uint16_t address, uint8_t * bp_handler)
240 {
241 }
242
243 void zremove_breakpoint(z80_context * context, uint16_t address)
244 {
245 }