1/*
2 * QEMU DMA emulation
3 *
4 * Copyright (c) 2003-2004 Vassili Karpov (malc)
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a copy
7 * of this software and associated documentation files (the "Software"), to deal
8 * in the Software without restriction, including without limitation the rights
9 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10 * copies of the Software, and to permit persons to whom the Software is
11 * furnished to do so, subject to the following conditions:
12 *
13 * The above copyright notice and this permission notice shall be included in
14 * all copies or substantial portions of the Software.
15 *
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
22 * THE SOFTWARE.
23 */
24
25#include "qemu/osdep.h"
26#include "hw/isa/isa.h"
27#include "hw/qdev-properties.h"
28#include "migration/vmstate.h"
29#include "hw/dma/i8257.h"
30#include "qemu/main-loop.h"
31#include "qemu/module.h"
32#include "qemu/log.h"
33#include "trace.h"
34
35#define I8257(obj) \
36 OBJECT_CHECK(I8257State, (obj), TYPE_I8257)
37
38/* #define DEBUG_DMA */
39
40#define dolog(...) fprintf (stderr, "dma: " __VA_ARGS__)
41#ifdef DEBUG_DMA
42#define linfo(...) fprintf (stderr, "dma: " __VA_ARGS__)
43#define ldebug(...) fprintf (stderr, "dma: " __VA_ARGS__)
44#else
45#define linfo(...)
46#define ldebug(...)
47#endif
48
49#define ADDR 0
50#define COUNT 1
51
52enum {
53 CMD_MEMORY_TO_MEMORY = 0x01,
54 CMD_FIXED_ADDRESS = 0x02,
55 CMD_BLOCK_CONTROLLER = 0x04,
56 CMD_COMPRESSED_TIME = 0x08,
57 CMD_CYCLIC_PRIORITY = 0x10,
58 CMD_EXTENDED_WRITE = 0x20,
59 CMD_LOW_DREQ = 0x40,
60 CMD_LOW_DACK = 0x80,
61 CMD_NOT_SUPPORTED = CMD_MEMORY_TO_MEMORY | CMD_FIXED_ADDRESS
62 | CMD_COMPRESSED_TIME | CMD_CYCLIC_PRIORITY | CMD_EXTENDED_WRITE
63 | CMD_LOW_DREQ | CMD_LOW_DACK
64
65};
66
67static void i8257_dma_run(void *opaque);
68
69static const int channels[8] = {-1, 2, 3, 1, -1, -1, -1, 0};
70
71static void i8257_write_page(void *opaque, uint32_t nport, uint32_t data)
72{
73 I8257State *d = opaque;
74 int ichan;
75
76 ichan = channels[nport & 7];
77 if (-1 == ichan) {
78 dolog ("invalid channel %#x %#x\n", nport, data);
79 return;
80 }
81 d->regs[ichan].page = data;
82}
83
84static void i8257_write_pageh(void *opaque, uint32_t nport, uint32_t data)
85{
86 I8257State *d = opaque;
87 int ichan;
88
89 ichan = channels[nport & 7];
90 if (-1 == ichan) {
91 dolog ("invalid channel %#x %#x\n", nport, data);
92 return;
93 }
94 d->regs[ichan].pageh = data;
95}
96
97static uint32_t i8257_read_page(void *opaque, uint32_t nport)
98{
99 I8257State *d = opaque;
100 int ichan;
101
102 ichan = channels[nport & 7];
103 if (-1 == ichan) {
104 dolog ("invalid channel read %#x\n", nport);
105 return 0;
106 }
107 return d->regs[ichan].page;
108}
109
110static uint32_t i8257_read_pageh(void *opaque, uint32_t nport)
111{
112 I8257State *d = opaque;
113 int ichan;
114
115 ichan = channels[nport & 7];
116 if (-1 == ichan) {
117 dolog ("invalid channel read %#x\n", nport);
118 return 0;
119 }
120 return d->regs[ichan].pageh;
121}
122
123static inline void i8257_init_chan(I8257State *d, int ichan)
124{
125 I8257Regs *r;
126
127 r = d->regs + ichan;
128 r->now[ADDR] = r->base[ADDR] << d->dshift;
129 r->now[COUNT] = 0;
130}
131
132static inline int i8257_getff(I8257State *d)
133{
134 int ff;
135
136 ff = d->flip_flop;
137 d->flip_flop = !ff;
138 return ff;
139}
140
141static uint64_t i8257_read_chan(void *opaque, hwaddr nport, unsigned size)
142{
143 I8257State *d = opaque;
144 int ichan, nreg, iport, ff, val, dir;
145 I8257Regs *r;
146
147 iport = (nport >> d->dshift) & 0x0f;
148 ichan = iport >> 1;
149 nreg = iport & 1;
150 r = d->regs + ichan;
151
152 dir = ((r->mode >> 5) & 1) ? -1 : 1;
153 ff = i8257_getff(d);
154 if (nreg)
155 val = (r->base[COUNT] << d->dshift) - r->now[COUNT];
156 else
157 val = r->now[ADDR] + r->now[COUNT] * dir;
158
159 ldebug ("read_chan %#x -> %d\n", iport, val);
160 return (val >> (d->dshift + (ff << 3))) & 0xff;
161}
162
163static void i8257_write_chan(void *opaque, hwaddr nport, uint64_t data,
164 unsigned int size)
165{
166 I8257State *d = opaque;
167 int iport, ichan, nreg;
168 I8257Regs *r;
169
170 iport = (nport >> d->dshift) & 0x0f;
171 ichan = iport >> 1;
172 nreg = iport & 1;
173 r = d->regs + ichan;
174 if (i8257_getff(d)) {
175 r->base[nreg] = (r->base[nreg] & 0xff) | ((data << 8) & 0xff00);
176 i8257_init_chan(d, ichan);
177 } else {
178 r->base[nreg] = (r->base[nreg] & 0xff00) | (data & 0xff);
179 }
180}
181
182static void i8257_write_cont(void *opaque, hwaddr nport, uint64_t data,
183 unsigned int size)
184{
185 I8257State *d = opaque;
186 int iport, ichan = 0;
187
188 iport = (nport >> d->dshift) & 0x0f;
189 switch (iport) {
190 case 0x00: /* command */
191 if ((data != 0) && (data & CMD_NOT_SUPPORTED)) {
192 qemu_log_mask(LOG_UNIMP, "%s: cmd 0x%02"PRIx64" not supported\n",
193 __func__, data);
194 return;
195 }
196 d->command = data;
197 break;
198
199 case 0x01:
200 ichan = data & 3;
201 if (data & 4) {
202 d->status |= 1 << (ichan + 4);
203 }
204 else {
205 d->status &= ~(1 << (ichan + 4));
206 }
207 d->status &= ~(1 << ichan);
208 i8257_dma_run(d);
209 break;
210
211 case 0x02: /* single mask */
212 if (data & 4)
213 d->mask |= 1 << (data & 3);
214 else
215 d->mask &= ~(1 << (data & 3));
216 i8257_dma_run(d);
217 break;
218
219 case 0x03: /* mode */
220 {
221 ichan = data & 3;
222#ifdef DEBUG_DMA
223 {
224 int op, ai, dir, opmode;
225 op = (data >> 2) & 3;
226 ai = (data >> 4) & 1;
227 dir = (data >> 5) & 1;
228 opmode = (data >> 6) & 3;
229
230 linfo ("ichan %d, op %d, ai %d, dir %d, opmode %d\n",
231 ichan, op, ai, dir, opmode);
232 }
233#endif
234 d->regs[ichan].mode = data;
235 break;
236 }
237
238 case 0x04: /* clear flip flop */
239 d->flip_flop = 0;
240 break;
241
242 case 0x05: /* reset */
243 d->flip_flop = 0;
244 d->mask = ~0;
245 d->status = 0;
246 d->command = 0;
247 break;
248
249 case 0x06: /* clear mask for all channels */
250 d->mask = 0;
251 i8257_dma_run(d);
252 break;
253
254 case 0x07: /* write mask for all channels */
255 d->mask = data;
256 i8257_dma_run(d);
257 break;
258
259 default:
260 dolog ("unknown iport %#x\n", iport);
261 break;
262 }
263
264#ifdef DEBUG_DMA
265 if (0xc != iport) {
266 linfo ("write_cont: nport %#06x, ichan % 2d, val %#06x\n",
267 nport, ichan, data);
268 }
269#endif
270}
271
272static uint64_t i8257_read_cont(void *opaque, hwaddr nport, unsigned size)
273{
274 I8257State *d = opaque;
275 int iport, val;
276
277 iport = (nport >> d->dshift) & 0x0f;
278 switch (iport) {
279 case 0x00: /* status */
280 val = d->status;
281 d->status &= 0xf0;
282 break;
283 case 0x01: /* mask */
284 val = d->mask;
285 break;
286 default:
287 val = 0;
288 break;
289 }
290
291 ldebug ("read_cont: nport %#06x, iport %#04x val %#x\n", nport, iport, val);
292 return val;
293}
294
295static IsaDmaTransferMode i8257_dma_get_transfer_mode(IsaDma *obj, int nchan)
296{
297 I8257State *d = I8257(obj);
298 return (d->regs[nchan & 3].mode >> 2) & 3;
299}
300
301static bool i8257_dma_has_autoinitialization(IsaDma *obj, int nchan)
302{
303 I8257State *d = I8257(obj);
304 return (d->regs[nchan & 3].mode >> 4) & 1;
305}
306
307static void i8257_dma_hold_DREQ(IsaDma *obj, int nchan)
308{
309 I8257State *d = I8257(obj);
310 int ichan;
311
312 ichan = nchan & 3;
313 d->status |= 1 << (ichan + 4);
314 i8257_dma_run(d);
315}
316
317static void i8257_dma_release_DREQ(IsaDma *obj, int nchan)
318{
319 I8257State *d = I8257(obj);
320 int ichan;
321
322 ichan = nchan & 3;
323 d->status &= ~(1 << (ichan + 4));
324 i8257_dma_run(d);
325}
326
327static void i8257_channel_run(I8257State *d, int ichan)
328{
329 int ncont = d->dshift;
330 int n;
331 I8257Regs *r = &d->regs[ichan];
332#ifdef DEBUG_DMA
333 int dir, opmode;
334
335 dir = (r->mode >> 5) & 1;
336 opmode = (r->mode >> 6) & 3;
337
338 if (dir) {
339 dolog ("DMA in address decrement mode\n");
340 }
341 if (opmode != 1) {
342 dolog ("DMA not in single mode select %#x\n", opmode);
343 }
344#endif
345
346 n = r->transfer_handler (r->opaque, ichan + (ncont << 2),
347 r->now[COUNT], (r->base[COUNT] + 1) << ncont);
348 r->now[COUNT] = n;
349 ldebug ("dma_pos %d size %d\n", n, (r->base[COUNT] + 1) << ncont);
350 if (n == (r->base[COUNT] + 1) << ncont) {
351 ldebug("transfer done\n");
352 d->status |= (1 << ichan);
353 }
354}
355
356static void i8257_dma_run(void *opaque)
357{
358 I8257State *d = opaque;
359 int ichan;
360 int rearm = 0;
361
362 if (d->running) {
363 rearm = 1;
364 goto out;
365 } else {
366 d->running = 1;
367 }
368
369 for (ichan = 0; ichan < 4; ichan++) {
370 int mask;
371
372 mask = 1 << ichan;
373
374 if ((0 == (d->mask & mask)) && (0 != (d->status & (mask << 4)))) {
375 i8257_channel_run(d, ichan);
376 rearm = 1;
377 }
378 }
379
380 d->running = 0;
381out:
382 if (rearm) {
383 qemu_bh_schedule_idle(d->dma_bh);
384 d->dma_bh_scheduled = true;
385 }
386}
387
388static void i8257_dma_register_channel(IsaDma *obj, int nchan,
389 IsaDmaTransferHandler transfer_handler,
390 void *opaque)
391{
392 I8257State *d = I8257(obj);
393 I8257Regs *r;
394 int ichan;
395
396 ichan = nchan & 3;
397
398 r = d->regs + ichan;
399 r->transfer_handler = transfer_handler;
400 r->opaque = opaque;
401}
402
403static int i8257_dma_read_memory(IsaDma *obj, int nchan, void *buf, int pos,
404 int len)
405{
406 I8257State *d = I8257(obj);
407 I8257Regs *r = &d->regs[nchan & 3];
408 hwaddr addr = ((r->pageh & 0x7f) << 24) | (r->page << 16) | r->now[ADDR];
409
410 if (r->mode & 0x20) {
411 int i;
412 uint8_t *p = buf;
413
414 cpu_physical_memory_read (addr - pos - len, buf, len);
415 /* What about 16bit transfers? */
416 for (i = 0; i < len >> 1; i++) {
417 uint8_t b = p[len - i - 1];
418 p[i] = b;
419 }
420 }
421 else
422 cpu_physical_memory_read (addr + pos, buf, len);
423
424 return len;
425}
426
427static int i8257_dma_write_memory(IsaDma *obj, int nchan, void *buf, int pos,
428 int len)
429{
430 I8257State *s = I8257(obj);
431 I8257Regs *r = &s->regs[nchan & 3];
432 hwaddr addr = ((r->pageh & 0x7f) << 24) | (r->page << 16) | r->now[ADDR];
433
434 if (r->mode & 0x20) {
435 int i;
436 uint8_t *p = buf;
437
438 cpu_physical_memory_write (addr - pos - len, buf, len);
439 /* What about 16bit transfers? */
440 for (i = 0; i < len; i++) {
441 uint8_t b = p[len - i - 1];
442 p[i] = b;
443 }
444 }
445 else
446 cpu_physical_memory_write (addr + pos, buf, len);
447
448 return len;
449}
450
451/* request the emulator to transfer a new DMA memory block ASAP (even
452 * if the idle bottom half would not have exited the iothread yet).
453 */
454static void i8257_dma_schedule(IsaDma *obj)
455{
456 I8257State *d = I8257(obj);
457 if (d->dma_bh_scheduled) {
458 qemu_notify_event();
459 }
460}
461
462static void i8257_reset(DeviceState *dev)
463{
464 I8257State *d = I8257(dev);
465 i8257_write_cont(d, (0x05 << d->dshift), 0, 1);
466}
467
468static int i8257_phony_handler(void *opaque, int nchan, int dma_pos,
469 int dma_len)
470{
471 trace_i8257_unregistered_dma(nchan, dma_pos, dma_len);
472 return dma_pos;
473}
474
475
476static const MemoryRegionOps channel_io_ops = {
477 .read = i8257_read_chan,
478 .write = i8257_write_chan,
479 .endianness = DEVICE_NATIVE_ENDIAN,
480 .impl = {
481 .min_access_size = 1,
482 .max_access_size = 1,
483 },
484};
485
486/* IOport from page_base */
487static const MemoryRegionPortio page_portio_list[] = {
488 { 0x01, 3, 1, .write = i8257_write_page, .read = i8257_read_page, },
489 { 0x07, 1, 1, .write = i8257_write_page, .read = i8257_read_page, },
490 PORTIO_END_OF_LIST(),
491};
492
493/* IOport from pageh_base */
494static const MemoryRegionPortio pageh_portio_list[] = {
495 { 0x01, 3, 1, .write = i8257_write_pageh, .read = i8257_read_pageh, },
496 { 0x07, 3, 1, .write = i8257_write_pageh, .read = i8257_read_pageh, },
497 PORTIO_END_OF_LIST(),
498};
499
500static const MemoryRegionOps cont_io_ops = {
501 .read = i8257_read_cont,
502 .write = i8257_write_cont,
503 .endianness = DEVICE_NATIVE_ENDIAN,
504 .impl = {
505 .min_access_size = 1,
506 .max_access_size = 1,
507 },
508};
509
510static const VMStateDescription vmstate_i8257_regs = {
511 .name = "dma_regs",
512 .version_id = 1,
513 .minimum_version_id = 1,
514 .fields = (VMStateField[]) {
515 VMSTATE_INT32_ARRAY(now, I8257Regs, 2),
516 VMSTATE_UINT16_ARRAY(base, I8257Regs, 2),
517 VMSTATE_UINT8(mode, I8257Regs),
518 VMSTATE_UINT8(page, I8257Regs),
519 VMSTATE_UINT8(pageh, I8257Regs),
520 VMSTATE_UINT8(dack, I8257Regs),
521 VMSTATE_UINT8(eop, I8257Regs),
522 VMSTATE_END_OF_LIST()
523 }
524};
525
526static int i8257_post_load(void *opaque, int version_id)
527{
528 I8257State *d = opaque;
529 i8257_dma_run(d);
530
531 return 0;
532}
533
534static const VMStateDescription vmstate_i8257 = {
535 .name = "dma",
536 .version_id = 1,
537 .minimum_version_id = 1,
538 .post_load = i8257_post_load,
539 .fields = (VMStateField[]) {
540 VMSTATE_UINT8(command, I8257State),
541 VMSTATE_UINT8(mask, I8257State),
542 VMSTATE_UINT8(flip_flop, I8257State),
543 VMSTATE_INT32(dshift, I8257State),
544 VMSTATE_STRUCT_ARRAY(regs, I8257State, 4, 1, vmstate_i8257_regs,
545 I8257Regs),
546 VMSTATE_END_OF_LIST()
547 }
548};
549
550static void i8257_realize(DeviceState *dev, Error **errp)
551{
552 ISADevice *isa = ISA_DEVICE(dev);
553 I8257State *d = I8257(dev);
554 int i;
555
556 memory_region_init_io(&d->channel_io, NULL, &channel_io_ops, d,
557 "dma-chan", 8 << d->dshift);
558 memory_region_add_subregion(isa_address_space_io(isa),
559 d->base, &d->channel_io);
560
561 isa_register_portio_list(isa, &d->portio_page,
562 d->page_base, page_portio_list, d,
563 "dma-page");
564 if (d->pageh_base >= 0) {
565 isa_register_portio_list(isa, &d->portio_pageh,
566 d->pageh_base, pageh_portio_list, d,
567 "dma-pageh");
568 }
569
570 memory_region_init_io(&d->cont_io, OBJECT(isa), &cont_io_ops, d,
571 "dma-cont", 8 << d->dshift);
572 memory_region_add_subregion(isa_address_space_io(isa),
573 d->base + (8 << d->dshift), &d->cont_io);
574
575 for (i = 0; i < ARRAY_SIZE(d->regs); ++i) {
576 d->regs[i].transfer_handler = i8257_phony_handler;
577 }
578
579 d->dma_bh = qemu_bh_new(i8257_dma_run, d);
580}
581
582static Property i8257_properties[] = {
583 DEFINE_PROP_INT32("base", I8257State, base, 0x00),
584 DEFINE_PROP_INT32("page-base", I8257State, page_base, 0x80),
585 DEFINE_PROP_INT32("pageh-base", I8257State, pageh_base, 0x480),
586 DEFINE_PROP_INT32("dshift", I8257State, dshift, 0),
587 DEFINE_PROP_END_OF_LIST()
588};
589
590static void i8257_class_init(ObjectClass *klass, void *data)
591{
592 DeviceClass *dc = DEVICE_CLASS(klass);
593 IsaDmaClass *idc = ISADMA_CLASS(klass);
594
595 dc->realize = i8257_realize;
596 dc->reset = i8257_reset;
597 dc->vmsd = &vmstate_i8257;
598 dc->props = i8257_properties;
599
600 idc->get_transfer_mode = i8257_dma_get_transfer_mode;
601 idc->has_autoinitialization = i8257_dma_has_autoinitialization;
602 idc->read_memory = i8257_dma_read_memory;
603 idc->write_memory = i8257_dma_write_memory;
604 idc->hold_DREQ = i8257_dma_hold_DREQ;
605 idc->release_DREQ = i8257_dma_release_DREQ;
606 idc->schedule = i8257_dma_schedule;
607 idc->register_channel = i8257_dma_register_channel;
608 /* Reason: needs to be wired up by isa_bus_dma() to work */
609 dc->user_creatable = false;
610}
611
612static const TypeInfo i8257_info = {
613 .name = TYPE_I8257,
614 .parent = TYPE_ISA_DEVICE,
615 .instance_size = sizeof(I8257State),
616 .class_init = i8257_class_init,
617 .interfaces = (InterfaceInfo[]) {
618 { TYPE_ISADMA },
619 { }
620 }
621};
622
623static void i8257_register_types(void)
624{
625 type_register_static(&i8257_info);
626}
627
628type_init(i8257_register_types)
629
630void i8257_dma_init(ISABus *bus, bool high_page_enable)
631{
632 ISADevice *isa1, *isa2;
633 DeviceState *d;
634
635 isa1 = isa_create(bus, TYPE_I8257);
636 d = DEVICE(isa1);
637 qdev_prop_set_int32(d, "base", 0x00);
638 qdev_prop_set_int32(d, "page-base", 0x80);
639 qdev_prop_set_int32(d, "pageh-base", high_page_enable ? 0x480 : -1);
640 qdev_prop_set_int32(d, "dshift", 0);
641 qdev_init_nofail(d);
642
643 isa2 = isa_create(bus, TYPE_I8257);
644 d = DEVICE(isa2);
645 qdev_prop_set_int32(d, "base", 0xc0);
646 qdev_prop_set_int32(d, "page-base", 0x88);
647 qdev_prop_set_int32(d, "pageh-base", high_page_enable ? 0x488 : -1);
648 qdev_prop_set_int32(d, "dshift", 1);
649 qdev_init_nofail(d);
650
651 isa_bus_dma(bus, ISADMA(isa1), ISADMA(isa2));
652}
653