xref: /openbmc/qemu/hw/dma/etraxfs_dma.c (revision 09a274d8)
1 /*
2  * QEMU ETRAX DMA Controller.
3  *
4  * Copyright (c) 2008 Edgar E. Iglesias, Axis Communications AB.
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 #include "qemu/osdep.h"
25 #include "hw/hw.h"
26 #include "exec/address-spaces.h"
27 #include "qemu-common.h"
28 #include "sysemu/sysemu.h"
29 
30 #include "hw/cris/etraxfs_dma.h"
31 
32 #define D(x)
33 
34 #define RW_DATA           (0x0 / 4)
35 #define RW_SAVED_DATA     (0x58 / 4)
36 #define RW_SAVED_DATA_BUF (0x5c / 4)
37 #define RW_GROUP          (0x60 / 4)
38 #define RW_GROUP_DOWN     (0x7c / 4)
39 #define RW_CMD            (0x80 / 4)
40 #define RW_CFG            (0x84 / 4)
41 #define RW_STAT           (0x88 / 4)
42 #define RW_INTR_MASK      (0x8c / 4)
43 #define RW_ACK_INTR       (0x90 / 4)
44 #define R_INTR            (0x94 / 4)
45 #define R_MASKED_INTR     (0x98 / 4)
46 #define RW_STREAM_CMD     (0x9c / 4)
47 
48 #define DMA_REG_MAX       (0x100 / 4)
49 
50 /* descriptors */
51 
52 // ------------------------------------------------------------ dma_descr_group
53 typedef struct dma_descr_group {
54   uint32_t                      next;
55   unsigned                      eol        : 1;
56   unsigned                      tol        : 1;
57   unsigned                      bol        : 1;
58   unsigned                                 : 1;
59   unsigned                      intr       : 1;
60   unsigned                                 : 2;
61   unsigned                      en         : 1;
62   unsigned                                 : 7;
63   unsigned                      dis        : 1;
64   unsigned                      md         : 16;
65   struct dma_descr_group       *up;
66   union {
67     struct dma_descr_context   *context;
68     struct dma_descr_group     *group;
69   }                             down;
70 } dma_descr_group;
71 
72 // ---------------------------------------------------------- dma_descr_context
73 typedef struct dma_descr_context {
74   uint32_t                      next;
75   unsigned                      eol        : 1;
76   unsigned                                 : 3;
77   unsigned                      intr       : 1;
78   unsigned                                 : 1;
79   unsigned                      store_mode : 1;
80   unsigned                      en         : 1;
81   unsigned                                 : 7;
82   unsigned                      dis        : 1;
83   unsigned                      md0        : 16;
84   unsigned                      md1;
85   unsigned                      md2;
86   unsigned                      md3;
87   unsigned                      md4;
88   uint32_t                      saved_data;
89   uint32_t                      saved_data_buf;
90 } dma_descr_context;
91 
92 // ------------------------------------------------------------- dma_descr_data
93 typedef struct dma_descr_data {
94   uint32_t                      next;
95   uint32_t                      buf;
96   unsigned                      eol        : 1;
97   unsigned                                 : 2;
98   unsigned                      out_eop    : 1;
99   unsigned                      intr       : 1;
100   unsigned                      wait       : 1;
101   unsigned                                 : 2;
102   unsigned                                 : 3;
103   unsigned                      in_eop     : 1;
104   unsigned                                 : 4;
105   unsigned                      md         : 16;
106   uint32_t                      after;
107 } dma_descr_data;
108 
109 /* Constants */
110 enum {
111   regk_dma_ack_pkt                         = 0x00000100,
112   regk_dma_anytime                         = 0x00000001,
113   regk_dma_array                           = 0x00000008,
114   regk_dma_burst                           = 0x00000020,
115   regk_dma_client                          = 0x00000002,
116   regk_dma_copy_next                       = 0x00000010,
117   regk_dma_copy_up                         = 0x00000020,
118   regk_dma_data_at_eol                     = 0x00000001,
119   regk_dma_dis_c                           = 0x00000010,
120   regk_dma_dis_g                           = 0x00000020,
121   regk_dma_idle                            = 0x00000001,
122   regk_dma_intern                          = 0x00000004,
123   regk_dma_load_c                          = 0x00000200,
124   regk_dma_load_c_n                        = 0x00000280,
125   regk_dma_load_c_next                     = 0x00000240,
126   regk_dma_load_d                          = 0x00000140,
127   regk_dma_load_g                          = 0x00000300,
128   regk_dma_load_g_down                     = 0x000003c0,
129   regk_dma_load_g_next                     = 0x00000340,
130   regk_dma_load_g_up                       = 0x00000380,
131   regk_dma_next_en                         = 0x00000010,
132   regk_dma_next_pkt                        = 0x00000010,
133   regk_dma_no                              = 0x00000000,
134   regk_dma_only_at_wait                    = 0x00000000,
135   regk_dma_restore                         = 0x00000020,
136   regk_dma_rst                             = 0x00000001,
137   regk_dma_running                         = 0x00000004,
138   regk_dma_rw_cfg_default                  = 0x00000000,
139   regk_dma_rw_cmd_default                  = 0x00000000,
140   regk_dma_rw_intr_mask_default            = 0x00000000,
141   regk_dma_rw_stat_default                 = 0x00000101,
142   regk_dma_rw_stream_cmd_default           = 0x00000000,
143   regk_dma_save_down                       = 0x00000020,
144   regk_dma_save_up                         = 0x00000020,
145   regk_dma_set_reg                         = 0x00000050,
146   regk_dma_set_w_size1                     = 0x00000190,
147   regk_dma_set_w_size2                     = 0x000001a0,
148   regk_dma_set_w_size4                     = 0x000001c0,
149   regk_dma_stopped                         = 0x00000002,
150   regk_dma_store_c                         = 0x00000002,
151   regk_dma_store_descr                     = 0x00000000,
152   regk_dma_store_g                         = 0x00000004,
153   regk_dma_store_md                        = 0x00000001,
154   regk_dma_sw                              = 0x00000008,
155   regk_dma_update_down                     = 0x00000020,
156   regk_dma_yes                             = 0x00000001
157 };
158 
159 enum dma_ch_state
160 {
161 	RST = 1,
162 	STOPPED = 2,
163 	RUNNING = 4
164 };
165 
166 struct fs_dma_channel
167 {
168 	qemu_irq irq;
169 	struct etraxfs_dma_client *client;
170 
171 	/* Internal status.  */
172 	int stream_cmd_src;
173 	enum dma_ch_state state;
174 
175 	unsigned int input : 1;
176 	unsigned int eol : 1;
177 
178 	struct dma_descr_group current_g;
179 	struct dma_descr_context current_c;
180 	struct dma_descr_data current_d;
181 
182 	/* Control registers.  */
183 	uint32_t regs[DMA_REG_MAX];
184 };
185 
186 struct fs_dma_ctrl
187 {
188 	MemoryRegion mmio;
189 	int nr_channels;
190 	struct fs_dma_channel *channels;
191 
192         QEMUBH *bh;
193 };
194 
195 static void DMA_run(void *opaque);
196 static int channel_out_run(struct fs_dma_ctrl *ctrl, int c);
197 
198 static inline uint32_t channel_reg(struct fs_dma_ctrl *ctrl, int c, int reg)
199 {
200 	return ctrl->channels[c].regs[reg];
201 }
202 
203 static inline int channel_stopped(struct fs_dma_ctrl *ctrl, int c)
204 {
205 	return channel_reg(ctrl, c, RW_CFG) & 2;
206 }
207 
208 static inline int channel_en(struct fs_dma_ctrl *ctrl, int c)
209 {
210 	return (channel_reg(ctrl, c, RW_CFG) & 1)
211 		&& ctrl->channels[c].client;
212 }
213 
214 static inline int fs_channel(hwaddr addr)
215 {
216 	/* Every channel has a 0x2000 ctrl register map.  */
217 	return addr >> 13;
218 }
219 
220 #ifdef USE_THIS_DEAD_CODE
221 static void channel_load_g(struct fs_dma_ctrl *ctrl, int c)
222 {
223 	hwaddr addr = channel_reg(ctrl, c, RW_GROUP);
224 
225 	/* Load and decode. FIXME: handle endianness.  */
226 	cpu_physical_memory_read (addr,
227 				  (void *) &ctrl->channels[c].current_g,
228 				  sizeof ctrl->channels[c].current_g);
229 }
230 
231 static void dump_c(int ch, struct dma_descr_context *c)
232 {
233 	printf("%s ch=%d\n", __func__, ch);
234 	printf("next=%x\n", c->next);
235 	printf("saved_data=%x\n", c->saved_data);
236 	printf("saved_data_buf=%x\n", c->saved_data_buf);
237 	printf("eol=%x\n", (uint32_t) c->eol);
238 }
239 
240 static void dump_d(int ch, struct dma_descr_data *d)
241 {
242 	printf("%s ch=%d\n", __func__, ch);
243 	printf("next=%x\n", d->next);
244 	printf("buf=%x\n", d->buf);
245 	printf("after=%x\n", d->after);
246 	printf("intr=%x\n", (uint32_t) d->intr);
247 	printf("out_eop=%x\n", (uint32_t) d->out_eop);
248 	printf("in_eop=%x\n", (uint32_t) d->in_eop);
249 	printf("eol=%x\n", (uint32_t) d->eol);
250 }
251 #endif
252 
253 static void channel_load_c(struct fs_dma_ctrl *ctrl, int c)
254 {
255 	hwaddr addr = channel_reg(ctrl, c, RW_GROUP_DOWN);
256 
257 	/* Load and decode. FIXME: handle endianness.  */
258 	cpu_physical_memory_read (addr,
259 				  (void *) &ctrl->channels[c].current_c,
260 				  sizeof ctrl->channels[c].current_c);
261 
262 	D(dump_c(c, &ctrl->channels[c].current_c));
263 	/* I guess this should update the current pos.  */
264 	ctrl->channels[c].regs[RW_SAVED_DATA] =
265 		(uint32_t)(unsigned long)ctrl->channels[c].current_c.saved_data;
266 	ctrl->channels[c].regs[RW_SAVED_DATA_BUF] =
267 		(uint32_t)(unsigned long)ctrl->channels[c].current_c.saved_data_buf;
268 }
269 
270 static void channel_load_d(struct fs_dma_ctrl *ctrl, int c)
271 {
272 	hwaddr addr = channel_reg(ctrl, c, RW_SAVED_DATA);
273 
274 	/* Load and decode. FIXME: handle endianness.  */
275 	D(printf("%s ch=%d addr=" TARGET_FMT_plx "\n", __func__, c, addr));
276 	cpu_physical_memory_read (addr,
277 				  (void *) &ctrl->channels[c].current_d,
278 				  sizeof ctrl->channels[c].current_d);
279 
280 	D(dump_d(c, &ctrl->channels[c].current_d));
281 	ctrl->channels[c].regs[RW_DATA] = addr;
282 }
283 
284 static void channel_store_c(struct fs_dma_ctrl *ctrl, int c)
285 {
286 	hwaddr addr = channel_reg(ctrl, c, RW_GROUP_DOWN);
287 
288 	/* Encode and store. FIXME: handle endianness.  */
289 	D(printf("%s ch=%d addr=" TARGET_FMT_plx "\n", __func__, c, addr));
290 	D(dump_d(c, &ctrl->channels[c].current_d));
291 	cpu_physical_memory_write (addr,
292 				  (void *) &ctrl->channels[c].current_c,
293 				  sizeof ctrl->channels[c].current_c);
294 }
295 
296 static void channel_store_d(struct fs_dma_ctrl *ctrl, int c)
297 {
298 	hwaddr addr = channel_reg(ctrl, c, RW_SAVED_DATA);
299 
300 	/* Encode and store. FIXME: handle endianness.  */
301 	D(printf("%s ch=%d addr=" TARGET_FMT_plx "\n", __func__, c, addr));
302 	cpu_physical_memory_write (addr,
303 				  (void *) &ctrl->channels[c].current_d,
304 				  sizeof ctrl->channels[c].current_d);
305 }
306 
307 static inline void channel_stop(struct fs_dma_ctrl *ctrl, int c)
308 {
309 	/* FIXME:  */
310 }
311 
312 static inline void channel_start(struct fs_dma_ctrl *ctrl, int c)
313 {
314 	if (ctrl->channels[c].client)
315 	{
316 		ctrl->channels[c].eol = 0;
317 		ctrl->channels[c].state = RUNNING;
318 		if (!ctrl->channels[c].input)
319 			channel_out_run(ctrl, c);
320 	} else
321 		printf("WARNING: starting DMA ch %d with no client\n", c);
322 
323         qemu_bh_schedule_idle(ctrl->bh);
324 }
325 
326 static void channel_continue(struct fs_dma_ctrl *ctrl, int c)
327 {
328 	if (!channel_en(ctrl, c)
329 	    || channel_stopped(ctrl, c)
330 	    || ctrl->channels[c].state != RUNNING
331 	    /* Only reload the current data descriptor if it has eol set.  */
332 	    || !ctrl->channels[c].current_d.eol) {
333 		D(printf("continue failed ch=%d state=%d stopped=%d en=%d eol=%d\n",
334 			 c, ctrl->channels[c].state,
335 			 channel_stopped(ctrl, c),
336 			 channel_en(ctrl,c),
337 			 ctrl->channels[c].eol));
338 		D(dump_d(c, &ctrl->channels[c].current_d));
339 		return;
340 	}
341 
342 	/* Reload the current descriptor.  */
343 	channel_load_d(ctrl, c);
344 
345 	/* If the current descriptor cleared the eol flag and we had already
346 	   reached eol state, do the continue.  */
347 	if (!ctrl->channels[c].current_d.eol && ctrl->channels[c].eol) {
348 		D(printf("continue %d ok %x\n", c,
349 			 ctrl->channels[c].current_d.next));
350 		ctrl->channels[c].regs[RW_SAVED_DATA] =
351 			(uint32_t)(unsigned long)ctrl->channels[c].current_d.next;
352 		channel_load_d(ctrl, c);
353 		ctrl->channels[c].regs[RW_SAVED_DATA_BUF] =
354 			(uint32_t)(unsigned long)ctrl->channels[c].current_d.buf;
355 
356 		channel_start(ctrl, c);
357 	}
358 	ctrl->channels[c].regs[RW_SAVED_DATA_BUF] =
359 		(uint32_t)(unsigned long)ctrl->channels[c].current_d.buf;
360 }
361 
362 static void channel_stream_cmd(struct fs_dma_ctrl *ctrl, int c, uint32_t v)
363 {
364 	unsigned int cmd = v & ((1 << 10) - 1);
365 
366 	D(printf("%s ch=%d cmd=%x\n",
367 		 __func__, c, cmd));
368 	if (cmd & regk_dma_load_d) {
369 		channel_load_d(ctrl, c);
370 		if (cmd & regk_dma_burst)
371 			channel_start(ctrl, c);
372 	}
373 
374 	if (cmd & regk_dma_load_c) {
375 		channel_load_c(ctrl, c);
376 	}
377 }
378 
379 static void channel_update_irq(struct fs_dma_ctrl *ctrl, int c)
380 {
381 	D(printf("%s %d\n", __func__, c));
382         ctrl->channels[c].regs[R_INTR] &=
383 		~(ctrl->channels[c].regs[RW_ACK_INTR]);
384 
385         ctrl->channels[c].regs[R_MASKED_INTR] =
386 		ctrl->channels[c].regs[R_INTR]
387 		& ctrl->channels[c].regs[RW_INTR_MASK];
388 
389 	D(printf("%s: chan=%d masked_intr=%x\n", __func__,
390 		 c,
391 		 ctrl->channels[c].regs[R_MASKED_INTR]));
392 
393         qemu_set_irq(ctrl->channels[c].irq,
394 		     !!ctrl->channels[c].regs[R_MASKED_INTR]);
395 }
396 
397 static int channel_out_run(struct fs_dma_ctrl *ctrl, int c)
398 {
399 	uint32_t len;
400 	uint32_t saved_data_buf;
401 	unsigned char buf[2 * 1024];
402 
403 	struct dma_context_metadata meta;
404 	bool send_context = true;
405 
406 	if (ctrl->channels[c].eol)
407 		return 0;
408 
409 	do {
410 		bool out_eop;
411 		D(printf("ch=%d buf=%x after=%x\n",
412 			 c,
413 			 (uint32_t)ctrl->channels[c].current_d.buf,
414 			 (uint32_t)ctrl->channels[c].current_d.after));
415 
416 		if (send_context) {
417 			if (ctrl->channels[c].client->client.metadata_push) {
418 				meta.metadata = ctrl->channels[c].current_d.md;
419 				ctrl->channels[c].client->client.metadata_push(
420 					ctrl->channels[c].client->client.opaque,
421 					&meta);
422 			}
423 			send_context = false;
424 		}
425 
426 		channel_load_d(ctrl, c);
427 		saved_data_buf = channel_reg(ctrl, c, RW_SAVED_DATA_BUF);
428 		len = (uint32_t)(unsigned long)
429 			ctrl->channels[c].current_d.after;
430 		len -= saved_data_buf;
431 
432 		if (len > sizeof buf)
433 			len = sizeof buf;
434 		cpu_physical_memory_read (saved_data_buf, buf, len);
435 
436 		out_eop = ((saved_data_buf + len) ==
437 		           ctrl->channels[c].current_d.after) &&
438 			ctrl->channels[c].current_d.out_eop;
439 
440 		D(printf("channel %d pushes %x %u bytes eop=%u\n", c,
441 		         saved_data_buf, len, out_eop));
442 
443 		if (ctrl->channels[c].client->client.push) {
444                         if (len > 0) {
445 				ctrl->channels[c].client->client.push(
446 					ctrl->channels[c].client->client.opaque,
447 					buf, len, out_eop);
448 			}
449 		} else {
450 			printf("WARNING: DMA ch%d dataloss,"
451 			       " no attached client.\n", c);
452 		}
453 
454 		saved_data_buf += len;
455 
456 		if (saved_data_buf == (uint32_t)(unsigned long)
457 				ctrl->channels[c].current_d.after) {
458 			/* Done. Step to next.  */
459 			if (ctrl->channels[c].current_d.out_eop) {
460 				send_context = true;
461 			}
462 			if (ctrl->channels[c].current_d.intr) {
463 				/* data intr.  */
464 				D(printf("signal intr %d eol=%d\n",
465 					len, ctrl->channels[c].current_d.eol));
466 				ctrl->channels[c].regs[R_INTR] |= (1 << 2);
467 				channel_update_irq(ctrl, c);
468 			}
469 			channel_store_d(ctrl, c);
470 			if (ctrl->channels[c].current_d.eol) {
471 				D(printf("channel %d EOL\n", c));
472 				ctrl->channels[c].eol = 1;
473 
474 				/* Mark the context as disabled.  */
475 				ctrl->channels[c].current_c.dis = 1;
476 				channel_store_c(ctrl, c);
477 
478 				channel_stop(ctrl, c);
479 			} else {
480 				ctrl->channels[c].regs[RW_SAVED_DATA] =
481 					(uint32_t)(unsigned long)ctrl->
482 						channels[c].current_d.next;
483 				/* Load new descriptor.  */
484 				channel_load_d(ctrl, c);
485 				saved_data_buf = (uint32_t)(unsigned long)
486 					ctrl->channels[c].current_d.buf;
487 			}
488 
489 			ctrl->channels[c].regs[RW_SAVED_DATA_BUF] =
490 							saved_data_buf;
491 			D(dump_d(c, &ctrl->channels[c].current_d));
492 		}
493 		ctrl->channels[c].regs[RW_SAVED_DATA_BUF] = saved_data_buf;
494 	} while (!ctrl->channels[c].eol);
495 	return 1;
496 }
497 
498 static int channel_in_process(struct fs_dma_ctrl *ctrl, int c,
499 			      unsigned char *buf, int buflen, int eop)
500 {
501 	uint32_t len;
502 	uint32_t saved_data_buf;
503 
504 	if (ctrl->channels[c].eol == 1)
505 		return 0;
506 
507 	channel_load_d(ctrl, c);
508 	saved_data_buf = channel_reg(ctrl, c, RW_SAVED_DATA_BUF);
509 	len = (uint32_t)(unsigned long)ctrl->channels[c].current_d.after;
510 	len -= saved_data_buf;
511 
512 	if (len > buflen)
513 		len = buflen;
514 
515 	cpu_physical_memory_write (saved_data_buf, buf, len);
516 	saved_data_buf += len;
517 
518 	if (saved_data_buf ==
519 	    (uint32_t)(unsigned long)ctrl->channels[c].current_d.after
520 	    || eop) {
521 		uint32_t r_intr = ctrl->channels[c].regs[R_INTR];
522 
523 		D(printf("in dscr end len=%d\n",
524 			 ctrl->channels[c].current_d.after
525 			 - ctrl->channels[c].current_d.buf));
526 		ctrl->channels[c].current_d.after = saved_data_buf;
527 
528 		/* Done. Step to next.  */
529 		if (ctrl->channels[c].current_d.intr) {
530 			/* TODO: signal eop to the client.  */
531 			/* data intr.  */
532 			ctrl->channels[c].regs[R_INTR] |= 3;
533 		}
534 		if (eop) {
535 			ctrl->channels[c].current_d.in_eop = 1;
536 			ctrl->channels[c].regs[R_INTR] |= 8;
537 		}
538 		if (r_intr != ctrl->channels[c].regs[R_INTR])
539 			channel_update_irq(ctrl, c);
540 
541 		channel_store_d(ctrl, c);
542 		D(dump_d(c, &ctrl->channels[c].current_d));
543 
544 		if (ctrl->channels[c].current_d.eol) {
545 			D(printf("channel %d EOL\n", c));
546 			ctrl->channels[c].eol = 1;
547 
548 			/* Mark the context as disabled.  */
549 			ctrl->channels[c].current_c.dis = 1;
550 			channel_store_c(ctrl, c);
551 
552 			channel_stop(ctrl, c);
553 		} else {
554 			ctrl->channels[c].regs[RW_SAVED_DATA] =
555 				(uint32_t)(unsigned long)ctrl->
556 					channels[c].current_d.next;
557 			/* Load new descriptor.  */
558 			channel_load_d(ctrl, c);
559 			saved_data_buf = (uint32_t)(unsigned long)
560 				ctrl->channels[c].current_d.buf;
561 		}
562 	}
563 
564 	ctrl->channels[c].regs[RW_SAVED_DATA_BUF] = saved_data_buf;
565 	return len;
566 }
567 
568 static inline int channel_in_run(struct fs_dma_ctrl *ctrl, int c)
569 {
570 	if (ctrl->channels[c].client->client.pull) {
571 		ctrl->channels[c].client->client.pull(
572 			ctrl->channels[c].client->client.opaque);
573 		return 1;
574 	} else
575 		return 0;
576 }
577 
578 static uint32_t dma_rinvalid (void *opaque, hwaddr addr)
579 {
580         hw_error("Unsupported short raccess. reg=" TARGET_FMT_plx "\n", addr);
581         return 0;
582 }
583 
584 static uint64_t
585 dma_read(void *opaque, hwaddr addr, unsigned int size)
586 {
587         struct fs_dma_ctrl *ctrl = opaque;
588 	int c;
589 	uint32_t r = 0;
590 
591 	if (size != 4) {
592 		dma_rinvalid(opaque, addr);
593 	}
594 
595 	/* Make addr relative to this channel and bounded to nr regs.  */
596 	c = fs_channel(addr);
597 	addr &= 0xff;
598 	addr >>= 2;
599 	switch (addr)
600 	{
601 		case RW_STAT:
602 			r = ctrl->channels[c].state & 7;
603 			r |= ctrl->channels[c].eol << 5;
604 			r |= ctrl->channels[c].stream_cmd_src << 8;
605 			break;
606 
607 		default:
608 			r = ctrl->channels[c].regs[addr];
609 			D(printf ("%s c=%d addr=" TARGET_FMT_plx "\n",
610 				  __func__, c, addr));
611 			break;
612 	}
613 	return r;
614 }
615 
616 static void
617 dma_winvalid (void *opaque, hwaddr addr, uint32_t value)
618 {
619         hw_error("Unsupported short waccess. reg=" TARGET_FMT_plx "\n", addr);
620 }
621 
622 static void
623 dma_update_state(struct fs_dma_ctrl *ctrl, int c)
624 {
625 	if (ctrl->channels[c].regs[RW_CFG] & 2)
626 		ctrl->channels[c].state = STOPPED;
627 	if (!(ctrl->channels[c].regs[RW_CFG] & 1))
628 		ctrl->channels[c].state = RST;
629 }
630 
631 static void
632 dma_write(void *opaque, hwaddr addr,
633 	  uint64_t val64, unsigned int size)
634 {
635         struct fs_dma_ctrl *ctrl = opaque;
636 	uint32_t value = val64;
637 	int c;
638 
639 	if (size != 4) {
640 		dma_winvalid(opaque, addr, value);
641 	}
642 
643         /* Make addr relative to this channel and bounded to nr regs.  */
644 	c = fs_channel(addr);
645         addr &= 0xff;
646         addr >>= 2;
647         switch (addr)
648 	{
649 		case RW_DATA:
650 			ctrl->channels[c].regs[addr] = value;
651 			break;
652 
653 		case RW_CFG:
654 			ctrl->channels[c].regs[addr] = value;
655 			dma_update_state(ctrl, c);
656 			break;
657 		case RW_CMD:
658 			/* continue.  */
659 			if (value & ~1)
660 				printf("Invalid store to ch=%d RW_CMD %x\n",
661 				       c, value);
662 			ctrl->channels[c].regs[addr] = value;
663 			channel_continue(ctrl, c);
664 			break;
665 
666 		case RW_SAVED_DATA:
667 		case RW_SAVED_DATA_BUF:
668 		case RW_GROUP:
669 		case RW_GROUP_DOWN:
670 			ctrl->channels[c].regs[addr] = value;
671 			break;
672 
673 		case RW_ACK_INTR:
674 		case RW_INTR_MASK:
675 			ctrl->channels[c].regs[addr] = value;
676 			channel_update_irq(ctrl, c);
677 			if (addr == RW_ACK_INTR)
678 				ctrl->channels[c].regs[RW_ACK_INTR] = 0;
679 			break;
680 
681 		case RW_STREAM_CMD:
682 			if (value & ~1023)
683 				printf("Invalid store to ch=%d "
684 				       "RW_STREAMCMD %x\n",
685 				       c, value);
686 			ctrl->channels[c].regs[addr] = value;
687 			D(printf("stream_cmd ch=%d\n", c));
688 			channel_stream_cmd(ctrl, c, value);
689 			break;
690 
691 	        default:
692 			D(printf ("%s c=%d " TARGET_FMT_plx "\n",
693 				__func__, c, addr));
694 			break;
695         }
696 }
697 
698 static const MemoryRegionOps dma_ops = {
699 	.read = dma_read,
700 	.write = dma_write,
701 	.endianness = DEVICE_NATIVE_ENDIAN,
702 	.valid = {
703 		.min_access_size = 1,
704 		.max_access_size = 4
705 	}
706 };
707 
708 static int etraxfs_dmac_run(void *opaque)
709 {
710 	struct fs_dma_ctrl *ctrl = opaque;
711 	int i;
712 	int p = 0;
713 
714 	for (i = 0;
715 	     i < ctrl->nr_channels;
716 	     i++)
717 	{
718 		if (ctrl->channels[i].state == RUNNING)
719 		{
720 			if (ctrl->channels[i].input) {
721 				p += channel_in_run(ctrl, i);
722 			} else {
723 				p += channel_out_run(ctrl, i);
724 			}
725 		}
726 	}
727 	return p;
728 }
729 
730 int etraxfs_dmac_input(struct etraxfs_dma_client *client,
731 		       void *buf, int len, int eop)
732 {
733 	return channel_in_process(client->ctrl, client->channel,
734 				  buf, len, eop);
735 }
736 
737 /* Connect an IRQ line with a channel.  */
738 void etraxfs_dmac_connect(void *opaque, int c, qemu_irq *line, int input)
739 {
740 	struct fs_dma_ctrl *ctrl = opaque;
741 	ctrl->channels[c].irq = *line;
742 	ctrl->channels[c].input = input;
743 }
744 
745 void etraxfs_dmac_connect_client(void *opaque, int c,
746 				 struct etraxfs_dma_client *cl)
747 {
748 	struct fs_dma_ctrl *ctrl = opaque;
749 	cl->ctrl = ctrl;
750 	cl->channel = c;
751 	ctrl->channels[c].client = cl;
752 }
753 
754 
755 static void DMA_run(void *opaque)
756 {
757     struct fs_dma_ctrl *etraxfs_dmac = opaque;
758     int p = 1;
759 
760     if (runstate_is_running())
761         p = etraxfs_dmac_run(etraxfs_dmac);
762 
763     if (p)
764         qemu_bh_schedule_idle(etraxfs_dmac->bh);
765 }
766 
767 void *etraxfs_dmac_init(hwaddr base, int nr_channels)
768 {
769 	struct fs_dma_ctrl *ctrl = NULL;
770 
771 	ctrl = g_malloc0(sizeof *ctrl);
772 
773         ctrl->bh = qemu_bh_new(DMA_run, ctrl);
774 
775 	ctrl->nr_channels = nr_channels;
776 	ctrl->channels = g_malloc0(sizeof ctrl->channels[0] * nr_channels);
777 
778 	memory_region_init_io(&ctrl->mmio, NULL, &dma_ops, ctrl, "etraxfs-dma",
779 			      nr_channels * 0x2000);
780 	memory_region_add_subregion(get_system_memory(), base, &ctrl->mmio);
781 
782 	return ctrl;
783 }
784