xref: /openbmc/qemu/hw/dma/pxa2xx_dma.c (revision 406d2aa2)
1 /*
2  * Intel XScale PXA255/270 DMA controller.
3  *
4  * Copyright (c) 2006 Openedhand Ltd.
5  * Copyright (c) 2006 Thorsten Zitterell
6  * Written by Andrzej Zaborowski <balrog@zabor.org>
7  *
8  * This code is licensed under the GPL.
9  */
10 
11 #include "qemu/osdep.h"
12 #include "hw/hw.h"
13 #include "hw/arm/pxa.h"
14 #include "hw/sysbus.h"
15 #include "qapi/error.h"
16 
17 #define PXA255_DMA_NUM_CHANNELS 16
18 #define PXA27X_DMA_NUM_CHANNELS 32
19 
20 #define PXA2XX_DMA_NUM_REQUESTS 75
21 
22 typedef struct {
23     uint32_t descr;
24     uint32_t src;
25     uint32_t dest;
26     uint32_t cmd;
27     uint32_t state;
28     int request;
29 } PXA2xxDMAChannel;
30 
31 #define TYPE_PXA2XX_DMA "pxa2xx-dma"
32 #define PXA2XX_DMA(obj) OBJECT_CHECK(PXA2xxDMAState, (obj), TYPE_PXA2XX_DMA)
33 
34 typedef struct PXA2xxDMAState {
35     SysBusDevice parent_obj;
36 
37     MemoryRegion iomem;
38     qemu_irq irq;
39 
40     uint32_t stopintr;
41     uint32_t eorintr;
42     uint32_t rasintr;
43     uint32_t startintr;
44     uint32_t endintr;
45 
46     uint32_t align;
47     uint32_t pio;
48 
49     int channels;
50     PXA2xxDMAChannel *chan;
51 
52     uint8_t req[PXA2XX_DMA_NUM_REQUESTS];
53 
54     /* Flag to avoid recursive DMA invocations.  */
55     int running;
56 } PXA2xxDMAState;
57 
58 #define DCSR0	0x0000	/* DMA Control / Status register for Channel 0 */
59 #define DCSR31	0x007c	/* DMA Control / Status register for Channel 31 */
60 #define DALGN	0x00a0	/* DMA Alignment register */
61 #define DPCSR	0x00a4	/* DMA Programmed I/O Control Status register */
62 #define DRQSR0	0x00e0	/* DMA DREQ<0> Status register */
63 #define DRQSR1	0x00e4	/* DMA DREQ<1> Status register */
64 #define DRQSR2	0x00e8	/* DMA DREQ<2> Status register */
65 #define DINT	0x00f0	/* DMA Interrupt register */
66 #define DRCMR0	0x0100	/* Request to Channel Map register 0 */
67 #define DRCMR63	0x01fc	/* Request to Channel Map register 63 */
68 #define D_CH0	0x0200	/* Channel 0 Descriptor start */
69 #define DRCMR64	0x1100	/* Request to Channel Map register 64 */
70 #define DRCMR74	0x1128	/* Request to Channel Map register 74 */
71 
72 /* Per-channel register */
73 #define DDADR	0x00
74 #define DSADR	0x01
75 #define DTADR	0x02
76 #define DCMD	0x03
77 
78 /* Bit-field masks */
79 #define DRCMR_CHLNUM		0x1f
80 #define DRCMR_MAPVLD		(1 << 7)
81 #define DDADR_STOP		(1 << 0)
82 #define DDADR_BREN		(1 << 1)
83 #define DCMD_LEN		0x1fff
84 #define DCMD_WIDTH(x)		(1 << ((((x) >> 14) & 3) - 1))
85 #define DCMD_SIZE(x)		(4 << (((x) >> 16) & 3))
86 #define DCMD_FLYBYT		(1 << 19)
87 #define DCMD_FLYBYS		(1 << 20)
88 #define DCMD_ENDIRQEN		(1 << 21)
89 #define DCMD_STARTIRQEN		(1 << 22)
90 #define DCMD_CMPEN		(1 << 25)
91 #define DCMD_FLOWTRG		(1 << 28)
92 #define DCMD_FLOWSRC		(1 << 29)
93 #define DCMD_INCTRGADDR		(1 << 30)
94 #define DCMD_INCSRCADDR		(1 << 31)
95 #define DCSR_BUSERRINTR		(1 << 0)
96 #define DCSR_STARTINTR		(1 << 1)
97 #define DCSR_ENDINTR		(1 << 2)
98 #define DCSR_STOPINTR		(1 << 3)
99 #define DCSR_RASINTR		(1 << 4)
100 #define DCSR_REQPEND		(1 << 8)
101 #define DCSR_EORINT		(1 << 9)
102 #define DCSR_CMPST		(1 << 10)
103 #define DCSR_MASKRUN		(1 << 22)
104 #define DCSR_RASIRQEN		(1 << 23)
105 #define DCSR_CLRCMPST		(1 << 24)
106 #define DCSR_SETCMPST		(1 << 25)
107 #define DCSR_EORSTOPEN		(1 << 26)
108 #define DCSR_EORJMPEN		(1 << 27)
109 #define DCSR_EORIRQEN		(1 << 28)
110 #define DCSR_STOPIRQEN		(1 << 29)
111 #define DCSR_NODESCFETCH	(1 << 30)
112 #define DCSR_RUN		(1 << 31)
113 
114 static inline void pxa2xx_dma_update(PXA2xxDMAState *s, int ch)
115 {
116     if (ch >= 0) {
117         if ((s->chan[ch].state & DCSR_STOPIRQEN) &&
118                 (s->chan[ch].state & DCSR_STOPINTR))
119             s->stopintr |= 1 << ch;
120         else
121             s->stopintr &= ~(1 << ch);
122 
123         if ((s->chan[ch].state & DCSR_EORIRQEN) &&
124                 (s->chan[ch].state & DCSR_EORINT))
125             s->eorintr |= 1 << ch;
126         else
127             s->eorintr &= ~(1 << ch);
128 
129         if ((s->chan[ch].state & DCSR_RASIRQEN) &&
130                 (s->chan[ch].state & DCSR_RASINTR))
131             s->rasintr |= 1 << ch;
132         else
133             s->rasintr &= ~(1 << ch);
134 
135         if (s->chan[ch].state & DCSR_STARTINTR)
136             s->startintr |= 1 << ch;
137         else
138             s->startintr &= ~(1 << ch);
139 
140         if (s->chan[ch].state & DCSR_ENDINTR)
141             s->endintr |= 1 << ch;
142         else
143             s->endintr &= ~(1 << ch);
144     }
145 
146     if (s->stopintr | s->eorintr | s->rasintr | s->startintr | s->endintr)
147         qemu_irq_raise(s->irq);
148     else
149         qemu_irq_lower(s->irq);
150 }
151 
152 static inline void pxa2xx_dma_descriptor_fetch(
153                 PXA2xxDMAState *s, int ch)
154 {
155     uint32_t desc[4];
156     hwaddr daddr = s->chan[ch].descr & ~0xf;
157     if ((s->chan[ch].descr & DDADR_BREN) && (s->chan[ch].state & DCSR_CMPST))
158         daddr += 32;
159 
160     cpu_physical_memory_read(daddr, desc, 16);
161     s->chan[ch].descr = desc[DDADR];
162     s->chan[ch].src = desc[DSADR];
163     s->chan[ch].dest = desc[DTADR];
164     s->chan[ch].cmd = desc[DCMD];
165 
166     if (s->chan[ch].cmd & DCMD_FLOWSRC)
167         s->chan[ch].src &= ~3;
168     if (s->chan[ch].cmd & DCMD_FLOWTRG)
169         s->chan[ch].dest &= ~3;
170 
171     if (s->chan[ch].cmd & (DCMD_CMPEN | DCMD_FLYBYS | DCMD_FLYBYT))
172         printf("%s: unsupported mode in channel %i\n", __FUNCTION__, ch);
173 
174     if (s->chan[ch].cmd & DCMD_STARTIRQEN)
175         s->chan[ch].state |= DCSR_STARTINTR;
176 }
177 
178 static void pxa2xx_dma_run(PXA2xxDMAState *s)
179 {
180     int c, srcinc, destinc;
181     uint32_t n, size;
182     uint32_t width;
183     uint32_t length;
184     uint8_t buffer[32];
185     PXA2xxDMAChannel *ch;
186 
187     if (s->running ++)
188         return;
189 
190     while (s->running) {
191         s->running = 1;
192         for (c = 0; c < s->channels; c ++) {
193             ch = &s->chan[c];
194 
195             while ((ch->state & DCSR_RUN) && !(ch->state & DCSR_STOPINTR)) {
196                 /* Test for pending requests */
197                 if ((ch->cmd & (DCMD_FLOWSRC | DCMD_FLOWTRG)) && !ch->request)
198                     break;
199 
200                 length = ch->cmd & DCMD_LEN;
201                 size = DCMD_SIZE(ch->cmd);
202                 width = DCMD_WIDTH(ch->cmd);
203 
204                 srcinc = (ch->cmd & DCMD_INCSRCADDR) ? width : 0;
205                 destinc = (ch->cmd & DCMD_INCTRGADDR) ? width : 0;
206 
207                 while (length) {
208                     size = MIN(length, size);
209 
210                     for (n = 0; n < size; n += width) {
211                         cpu_physical_memory_read(ch->src, buffer + n, width);
212                         ch->src += srcinc;
213                     }
214 
215                     for (n = 0; n < size; n += width) {
216                         cpu_physical_memory_write(ch->dest, buffer + n, width);
217                         ch->dest += destinc;
218                     }
219 
220                     length -= size;
221 
222                     if ((ch->cmd & (DCMD_FLOWSRC | DCMD_FLOWTRG)) &&
223                             !ch->request) {
224                         ch->state |= DCSR_EORINT;
225                         if (ch->state & DCSR_EORSTOPEN)
226                             ch->state |= DCSR_STOPINTR;
227                         if ((ch->state & DCSR_EORJMPEN) &&
228                                         !(ch->state & DCSR_NODESCFETCH))
229                             pxa2xx_dma_descriptor_fetch(s, c);
230                         break;
231 		    }
232                 }
233 
234                 ch->cmd = (ch->cmd & ~DCMD_LEN) | length;
235 
236                 /* Is the transfer complete now? */
237                 if (!length) {
238                     if (ch->cmd & DCMD_ENDIRQEN)
239                         ch->state |= DCSR_ENDINTR;
240 
241                     if ((ch->state & DCSR_NODESCFETCH) ||
242                                 (ch->descr & DDADR_STOP) ||
243                                 (ch->state & DCSR_EORSTOPEN)) {
244                         ch->state |= DCSR_STOPINTR;
245                         ch->state &= ~DCSR_RUN;
246 
247                         break;
248                     }
249 
250                     ch->state |= DCSR_STOPINTR;
251                     break;
252                 }
253             }
254         }
255 
256         s->running --;
257     }
258 }
259 
260 static uint64_t pxa2xx_dma_read(void *opaque, hwaddr offset,
261                                 unsigned size)
262 {
263     PXA2xxDMAState *s = (PXA2xxDMAState *) opaque;
264     unsigned int channel;
265 
266     if (size != 4) {
267         hw_error("%s: Bad access width\n", __FUNCTION__);
268         return 5;
269     }
270 
271     switch (offset) {
272     case DRCMR64 ... DRCMR74:
273         offset -= DRCMR64 - DRCMR0 - (64 << 2);
274         /* Fall through */
275     case DRCMR0 ... DRCMR63:
276         channel = (offset - DRCMR0) >> 2;
277         return s->req[channel];
278 
279     case DRQSR0:
280     case DRQSR1:
281     case DRQSR2:
282         return 0;
283 
284     case DCSR0 ... DCSR31:
285         channel = offset >> 2;
286 	if (s->chan[channel].request)
287             return s->chan[channel].state | DCSR_REQPEND;
288         return s->chan[channel].state;
289 
290     case DINT:
291         return s->stopintr | s->eorintr | s->rasintr |
292                 s->startintr | s->endintr;
293 
294     case DALGN:
295         return s->align;
296 
297     case DPCSR:
298         return s->pio;
299     }
300 
301     if (offset >= D_CH0 && offset < D_CH0 + (s->channels << 4)) {
302         channel = (offset - D_CH0) >> 4;
303         switch ((offset & 0x0f) >> 2) {
304         case DDADR:
305             return s->chan[channel].descr;
306         case DSADR:
307             return s->chan[channel].src;
308         case DTADR:
309             return s->chan[channel].dest;
310         case DCMD:
311             return s->chan[channel].cmd;
312         }
313     }
314 
315     hw_error("%s: Bad offset 0x" TARGET_FMT_plx "\n", __FUNCTION__, offset);
316     return 7;
317 }
318 
319 static void pxa2xx_dma_write(void *opaque, hwaddr offset,
320                              uint64_t value, unsigned size)
321 {
322     PXA2xxDMAState *s = (PXA2xxDMAState *) opaque;
323     unsigned int channel;
324 
325     if (size != 4) {
326         hw_error("%s: Bad access width\n", __FUNCTION__);
327         return;
328     }
329 
330     switch (offset) {
331     case DRCMR64 ... DRCMR74:
332         offset -= DRCMR64 - DRCMR0 - (64 << 2);
333         /* Fall through */
334     case DRCMR0 ... DRCMR63:
335         channel = (offset - DRCMR0) >> 2;
336 
337         if (value & DRCMR_MAPVLD)
338             if ((value & DRCMR_CHLNUM) > s->channels)
339                 hw_error("%s: Bad DMA channel %i\n",
340                          __FUNCTION__, (unsigned)value & DRCMR_CHLNUM);
341 
342         s->req[channel] = value;
343         break;
344 
345     case DRQSR0:
346     case DRQSR1:
347     case DRQSR2:
348         /* Nothing to do */
349         break;
350 
351     case DCSR0 ... DCSR31:
352         channel = offset >> 2;
353         s->chan[channel].state &= 0x0000071f & ~(value &
354                         (DCSR_EORINT | DCSR_ENDINTR |
355                          DCSR_STARTINTR | DCSR_BUSERRINTR));
356         s->chan[channel].state |= value & 0xfc800000;
357 
358         if (s->chan[channel].state & DCSR_STOPIRQEN)
359             s->chan[channel].state &= ~DCSR_STOPINTR;
360 
361         if (value & DCSR_NODESCFETCH) {
362             /* No-descriptor-fetch mode */
363             if (value & DCSR_RUN) {
364                 s->chan[channel].state &= ~DCSR_STOPINTR;
365                 pxa2xx_dma_run(s);
366             }
367         } else {
368             /* Descriptor-fetch mode */
369             if (value & DCSR_RUN) {
370                 s->chan[channel].state &= ~DCSR_STOPINTR;
371                 pxa2xx_dma_descriptor_fetch(s, channel);
372                 pxa2xx_dma_run(s);
373             }
374         }
375 
376         /* Shouldn't matter as our DMA is synchronous.  */
377         if (!(value & (DCSR_RUN | DCSR_MASKRUN)))
378             s->chan[channel].state |= DCSR_STOPINTR;
379 
380         if (value & DCSR_CLRCMPST)
381             s->chan[channel].state &= ~DCSR_CMPST;
382         if (value & DCSR_SETCMPST)
383             s->chan[channel].state |= DCSR_CMPST;
384 
385         pxa2xx_dma_update(s, channel);
386         break;
387 
388     case DALGN:
389         s->align = value;
390         break;
391 
392     case DPCSR:
393         s->pio = value & 0x80000001;
394         break;
395 
396     default:
397         if (offset >= D_CH0 && offset < D_CH0 + (s->channels << 4)) {
398             channel = (offset - D_CH0) >> 4;
399             switch ((offset & 0x0f) >> 2) {
400             case DDADR:
401                 s->chan[channel].descr = value;
402                 break;
403             case DSADR:
404                 s->chan[channel].src = value;
405                 break;
406             case DTADR:
407                 s->chan[channel].dest = value;
408                 break;
409             case DCMD:
410                 s->chan[channel].cmd = value;
411                 break;
412             default:
413                 goto fail;
414             }
415 
416             break;
417         }
418     fail:
419         hw_error("%s: Bad offset " TARGET_FMT_plx "\n", __FUNCTION__, offset);
420     }
421 }
422 
423 static const MemoryRegionOps pxa2xx_dma_ops = {
424     .read = pxa2xx_dma_read,
425     .write = pxa2xx_dma_write,
426     .endianness = DEVICE_NATIVE_ENDIAN,
427 };
428 
429 static void pxa2xx_dma_request(void *opaque, int req_num, int on)
430 {
431     PXA2xxDMAState *s = opaque;
432     int ch;
433     if (req_num < 0 || req_num >= PXA2XX_DMA_NUM_REQUESTS)
434         hw_error("%s: Bad DMA request %i\n", __FUNCTION__, req_num);
435 
436     if (!(s->req[req_num] & DRCMR_MAPVLD))
437         return;
438     ch = s->req[req_num] & DRCMR_CHLNUM;
439 
440     if (!s->chan[ch].request && on)
441         s->chan[ch].state |= DCSR_RASINTR;
442     else
443         s->chan[ch].state &= ~DCSR_RASINTR;
444     if (s->chan[ch].request && !on)
445         s->chan[ch].state |= DCSR_EORINT;
446 
447     s->chan[ch].request = on;
448     if (on) {
449         pxa2xx_dma_run(s);
450         pxa2xx_dma_update(s, ch);
451     }
452 }
453 
454 static void pxa2xx_dma_init(Object *obj)
455 {
456     DeviceState *dev = DEVICE(obj);
457     PXA2xxDMAState *s = PXA2XX_DMA(obj);
458     SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
459 
460     memset(s->req, 0, sizeof(uint8_t) * PXA2XX_DMA_NUM_REQUESTS);
461 
462     qdev_init_gpio_in(dev, pxa2xx_dma_request, PXA2XX_DMA_NUM_REQUESTS);
463 
464     memory_region_init_io(&s->iomem, obj, &pxa2xx_dma_ops, s,
465                           "pxa2xx.dma", 0x00010000);
466     sysbus_init_mmio(sbd, &s->iomem);
467     sysbus_init_irq(sbd, &s->irq);
468 }
469 
470 static void pxa2xx_dma_realize(DeviceState *dev, Error **errp)
471 {
472     PXA2xxDMAState *s = PXA2XX_DMA(dev);
473     int i;
474 
475     if (s->channels <= 0) {
476         error_setg(errp, "channels value invalid");
477         return;
478     }
479 
480     s->chan = g_new0(PXA2xxDMAChannel, s->channels);
481 
482     for (i = 0; i < s->channels; i ++)
483         s->chan[i].state = DCSR_STOPINTR;
484 }
485 
486 DeviceState *pxa27x_dma_init(hwaddr base, qemu_irq irq)
487 {
488     DeviceState *dev;
489 
490     dev = qdev_create(NULL, "pxa2xx-dma");
491     qdev_prop_set_int32(dev, "channels", PXA27X_DMA_NUM_CHANNELS);
492     qdev_init_nofail(dev);
493 
494     sysbus_mmio_map(SYS_BUS_DEVICE(dev), 0, base);
495     sysbus_connect_irq(SYS_BUS_DEVICE(dev), 0, irq);
496 
497     return dev;
498 }
499 
500 DeviceState *pxa255_dma_init(hwaddr base, qemu_irq irq)
501 {
502     DeviceState *dev;
503 
504     dev = qdev_create(NULL, "pxa2xx-dma");
505     qdev_prop_set_int32(dev, "channels", PXA27X_DMA_NUM_CHANNELS);
506     qdev_init_nofail(dev);
507 
508     sysbus_mmio_map(SYS_BUS_DEVICE(dev), 0, base);
509     sysbus_connect_irq(SYS_BUS_DEVICE(dev), 0, irq);
510 
511     return dev;
512 }
513 
514 static bool is_version_0(void *opaque, int version_id)
515 {
516     return version_id == 0;
517 }
518 
519 static VMStateDescription vmstate_pxa2xx_dma_chan = {
520     .name = "pxa2xx_dma_chan",
521     .version_id = 1,
522     .minimum_version_id = 1,
523     .fields = (VMStateField[]) {
524         VMSTATE_UINT32(descr, PXA2xxDMAChannel),
525         VMSTATE_UINT32(src, PXA2xxDMAChannel),
526         VMSTATE_UINT32(dest, PXA2xxDMAChannel),
527         VMSTATE_UINT32(cmd, PXA2xxDMAChannel),
528         VMSTATE_UINT32(state, PXA2xxDMAChannel),
529         VMSTATE_INT32(request, PXA2xxDMAChannel),
530         VMSTATE_END_OF_LIST(),
531     },
532 };
533 
534 static VMStateDescription vmstate_pxa2xx_dma = {
535     .name = "pxa2xx_dma",
536     .version_id = 1,
537     .minimum_version_id = 0,
538     .fields = (VMStateField[]) {
539         VMSTATE_UNUSED_TEST(is_version_0, 4),
540         VMSTATE_UINT32(stopintr, PXA2xxDMAState),
541         VMSTATE_UINT32(eorintr, PXA2xxDMAState),
542         VMSTATE_UINT32(rasintr, PXA2xxDMAState),
543         VMSTATE_UINT32(startintr, PXA2xxDMAState),
544         VMSTATE_UINT32(endintr, PXA2xxDMAState),
545         VMSTATE_UINT32(align, PXA2xxDMAState),
546         VMSTATE_UINT32(pio, PXA2xxDMAState),
547         VMSTATE_BUFFER(req, PXA2xxDMAState),
548         VMSTATE_STRUCT_VARRAY_POINTER_INT32(chan, PXA2xxDMAState, channels,
549                 vmstate_pxa2xx_dma_chan, PXA2xxDMAChannel),
550         VMSTATE_END_OF_LIST(),
551     },
552 };
553 
554 static Property pxa2xx_dma_properties[] = {
555     DEFINE_PROP_INT32("channels", PXA2xxDMAState, channels, -1),
556     DEFINE_PROP_END_OF_LIST(),
557 };
558 
559 static void pxa2xx_dma_class_init(ObjectClass *klass, void *data)
560 {
561     DeviceClass *dc = DEVICE_CLASS(klass);
562 
563     dc->desc = "PXA2xx DMA controller";
564     dc->vmsd = &vmstate_pxa2xx_dma;
565     dc->props = pxa2xx_dma_properties;
566     dc->realize = pxa2xx_dma_realize;
567 }
568 
569 static const TypeInfo pxa2xx_dma_info = {
570     .name          = TYPE_PXA2XX_DMA,
571     .parent        = TYPE_SYS_BUS_DEVICE,
572     .instance_size = sizeof(PXA2xxDMAState),
573     .instance_init = pxa2xx_dma_init,
574     .class_init    = pxa2xx_dma_class_init,
575 };
576 
577 static void pxa2xx_dma_register_types(void)
578 {
579     type_register_static(&pxa2xx_dma_info);
580 }
581 
582 type_init(pxa2xx_dma_register_types)
583