xref: /openbmc/qemu/hw/dma/etraxfs_dma.c (revision 8e6fe6b8)
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 "sysemu/sysemu.h"
28 
29 #include "hw/cris/etraxfs_dma.h"
30 
31 #define D(x)
32 
33 #define RW_DATA           (0x0 / 4)
34 #define RW_SAVED_DATA     (0x58 / 4)
35 #define RW_SAVED_DATA_BUF (0x5c / 4)
36 #define RW_GROUP          (0x60 / 4)
37 #define RW_GROUP_DOWN     (0x7c / 4)
38 #define RW_CMD            (0x80 / 4)
39 #define RW_CFG            (0x84 / 4)
40 #define RW_STAT           (0x88 / 4)
41 #define RW_INTR_MASK      (0x8c / 4)
42 #define RW_ACK_INTR       (0x90 / 4)
43 #define R_INTR            (0x94 / 4)
44 #define R_MASKED_INTR     (0x98 / 4)
45 #define RW_STREAM_CMD     (0x9c / 4)
46 
47 #define DMA_REG_MAX       (0x100 / 4)
48 
49 /* descriptors */
50 
51 // ------------------------------------------------------------ dma_descr_group
52 typedef struct dma_descr_group {
53   uint32_t                      next;
54   unsigned                      eol        : 1;
55   unsigned                      tol        : 1;
56   unsigned                      bol        : 1;
57   unsigned                                 : 1;
58   unsigned                      intr       : 1;
59   unsigned                                 : 2;
60   unsigned                      en         : 1;
61   unsigned                                 : 7;
62   unsigned                      dis        : 1;
63   unsigned                      md         : 16;
64   struct dma_descr_group       *up;
65   union {
66     struct dma_descr_context   *context;
67     struct dma_descr_group     *group;
68   }                             down;
69 } dma_descr_group;
70 
71 // ---------------------------------------------------------- dma_descr_context
72 typedef struct dma_descr_context {
73   uint32_t                      next;
74   unsigned                      eol        : 1;
75   unsigned                                 : 3;
76   unsigned                      intr       : 1;
77   unsigned                                 : 1;
78   unsigned                      store_mode : 1;
79   unsigned                      en         : 1;
80   unsigned                                 : 7;
81   unsigned                      dis        : 1;
82   unsigned                      md0        : 16;
83   unsigned                      md1;
84   unsigned                      md2;
85   unsigned                      md3;
86   unsigned                      md4;
87   uint32_t                      saved_data;
88   uint32_t                      saved_data_buf;
89 } dma_descr_context;
90 
91 // ------------------------------------------------------------- dma_descr_data
92 typedef struct dma_descr_data {
93   uint32_t                      next;
94   uint32_t                      buf;
95   unsigned                      eol        : 1;
96   unsigned                                 : 2;
97   unsigned                      out_eop    : 1;
98   unsigned                      intr       : 1;
99   unsigned                      wait       : 1;
100   unsigned                                 : 2;
101   unsigned                                 : 3;
102   unsigned                      in_eop     : 1;
103   unsigned                                 : 4;
104   unsigned                      md         : 16;
105   uint32_t                      after;
106 } dma_descr_data;
107 
108 /* Constants */
109 enum {
110   regk_dma_ack_pkt                         = 0x00000100,
111   regk_dma_anytime                         = 0x00000001,
112   regk_dma_array                           = 0x00000008,
113   regk_dma_burst                           = 0x00000020,
114   regk_dma_client                          = 0x00000002,
115   regk_dma_copy_next                       = 0x00000010,
116   regk_dma_copy_up                         = 0x00000020,
117   regk_dma_data_at_eol                     = 0x00000001,
118   regk_dma_dis_c                           = 0x00000010,
119   regk_dma_dis_g                           = 0x00000020,
120   regk_dma_idle                            = 0x00000001,
121   regk_dma_intern                          = 0x00000004,
122   regk_dma_load_c                          = 0x00000200,
123   regk_dma_load_c_n                        = 0x00000280,
124   regk_dma_load_c_next                     = 0x00000240,
125   regk_dma_load_d                          = 0x00000140,
126   regk_dma_load_g                          = 0x00000300,
127   regk_dma_load_g_down                     = 0x000003c0,
128   regk_dma_load_g_next                     = 0x00000340,
129   regk_dma_load_g_up                       = 0x00000380,
130   regk_dma_next_en                         = 0x00000010,
131   regk_dma_next_pkt                        = 0x00000010,
132   regk_dma_no                              = 0x00000000,
133   regk_dma_only_at_wait                    = 0x00000000,
134   regk_dma_restore                         = 0x00000020,
135   regk_dma_rst                             = 0x00000001,
136   regk_dma_running                         = 0x00000004,
137   regk_dma_rw_cfg_default                  = 0x00000000,
138   regk_dma_rw_cmd_default                  = 0x00000000,
139   regk_dma_rw_intr_mask_default            = 0x00000000,
140   regk_dma_rw_stat_default                 = 0x00000101,
141   regk_dma_rw_stream_cmd_default           = 0x00000000,
142   regk_dma_save_down                       = 0x00000020,
143   regk_dma_save_up                         = 0x00000020,
144   regk_dma_set_reg                         = 0x00000050,
145   regk_dma_set_w_size1                     = 0x00000190,
146   regk_dma_set_w_size2                     = 0x000001a0,
147   regk_dma_set_w_size4                     = 0x000001c0,
148   regk_dma_stopped                         = 0x00000002,
149   regk_dma_store_c                         = 0x00000002,
150   regk_dma_store_descr                     = 0x00000000,
151   regk_dma_store_g                         = 0x00000004,
152   regk_dma_store_md                        = 0x00000001,
153   regk_dma_sw                              = 0x00000008,
154   regk_dma_update_down                     = 0x00000020,
155   regk_dma_yes                             = 0x00000001
156 };
157 
158 enum dma_ch_state
159 {
160 	RST = 1,
161 	STOPPED = 2,
162 	RUNNING = 4
163 };
164 
165 struct fs_dma_channel
166 {
167 	qemu_irq irq;
168 	struct etraxfs_dma_client *client;
169 
170 	/* Internal status.  */
171 	int stream_cmd_src;
172 	enum dma_ch_state state;
173 
174 	unsigned int input : 1;
175 	unsigned int eol : 1;
176 
177 	struct dma_descr_group current_g;
178 	struct dma_descr_context current_c;
179 	struct dma_descr_data current_d;
180 
181 	/* Control registers.  */
182 	uint32_t regs[DMA_REG_MAX];
183 };
184 
185 struct fs_dma_ctrl
186 {
187 	MemoryRegion mmio;
188 	int nr_channels;
189 	struct fs_dma_channel *channels;
190 
191         QEMUBH *bh;
192 };
193 
194 static void DMA_run(void *opaque);
195 static int channel_out_run(struct fs_dma_ctrl *ctrl, int c);
196 
197 static inline uint32_t channel_reg(struct fs_dma_ctrl *ctrl, int c, int reg)
198 {
199 	return ctrl->channels[c].regs[reg];
200 }
201 
202 static inline int channel_stopped(struct fs_dma_ctrl *ctrl, int c)
203 {
204 	return channel_reg(ctrl, c, RW_CFG) & 2;
205 }
206 
207 static inline int channel_en(struct fs_dma_ctrl *ctrl, int c)
208 {
209 	return (channel_reg(ctrl, c, RW_CFG) & 1)
210 		&& ctrl->channels[c].client;
211 }
212 
213 static inline int fs_channel(hwaddr addr)
214 {
215 	/* Every channel has a 0x2000 ctrl register map.  */
216 	return addr >> 13;
217 }
218 
219 #ifdef USE_THIS_DEAD_CODE
220 static void channel_load_g(struct fs_dma_ctrl *ctrl, int c)
221 {
222 	hwaddr addr = channel_reg(ctrl, c, RW_GROUP);
223 
224 	/* Load and decode. FIXME: handle endianness.  */
225 	cpu_physical_memory_read (addr,
226 				  (void *) &ctrl->channels[c].current_g,
227 				  sizeof ctrl->channels[c].current_g);
228 }
229 
230 static void dump_c(int ch, struct dma_descr_context *c)
231 {
232 	printf("%s ch=%d\n", __func__, ch);
233 	printf("next=%x\n", c->next);
234 	printf("saved_data=%x\n", c->saved_data);
235 	printf("saved_data_buf=%x\n", c->saved_data_buf);
236 	printf("eol=%x\n", (uint32_t) c->eol);
237 }
238 
239 static void dump_d(int ch, struct dma_descr_data *d)
240 {
241 	printf("%s ch=%d\n", __func__, ch);
242 	printf("next=%x\n", d->next);
243 	printf("buf=%x\n", d->buf);
244 	printf("after=%x\n", d->after);
245 	printf("intr=%x\n", (uint32_t) d->intr);
246 	printf("out_eop=%x\n", (uint32_t) d->out_eop);
247 	printf("in_eop=%x\n", (uint32_t) d->in_eop);
248 	printf("eol=%x\n", (uint32_t) d->eol);
249 }
250 #endif
251 
252 static void channel_load_c(struct fs_dma_ctrl *ctrl, int c)
253 {
254 	hwaddr addr = channel_reg(ctrl, c, RW_GROUP_DOWN);
255 
256 	/* Load and decode. FIXME: handle endianness.  */
257 	cpu_physical_memory_read (addr,
258 				  (void *) &ctrl->channels[c].current_c,
259 				  sizeof ctrl->channels[c].current_c);
260 
261 	D(dump_c(c, &ctrl->channels[c].current_c));
262 	/* I guess this should update the current pos.  */
263 	ctrl->channels[c].regs[RW_SAVED_DATA] =
264 		(uint32_t)(unsigned long)ctrl->channels[c].current_c.saved_data;
265 	ctrl->channels[c].regs[RW_SAVED_DATA_BUF] =
266 		(uint32_t)(unsigned long)ctrl->channels[c].current_c.saved_data_buf;
267 }
268 
269 static void channel_load_d(struct fs_dma_ctrl *ctrl, int c)
270 {
271 	hwaddr addr = channel_reg(ctrl, c, RW_SAVED_DATA);
272 
273 	/* Load and decode. FIXME: handle endianness.  */
274 	D(printf("%s ch=%d addr=" TARGET_FMT_plx "\n", __func__, c, addr));
275 	cpu_physical_memory_read (addr,
276 				  (void *) &ctrl->channels[c].current_d,
277 				  sizeof ctrl->channels[c].current_d);
278 
279 	D(dump_d(c, &ctrl->channels[c].current_d));
280 	ctrl->channels[c].regs[RW_DATA] = addr;
281 }
282 
283 static void channel_store_c(struct fs_dma_ctrl *ctrl, int c)
284 {
285 	hwaddr addr = channel_reg(ctrl, c, RW_GROUP_DOWN);
286 
287 	/* Encode and store. FIXME: handle endianness.  */
288 	D(printf("%s ch=%d addr=" TARGET_FMT_plx "\n", __func__, c, addr));
289 	D(dump_d(c, &ctrl->channels[c].current_d));
290 	cpu_physical_memory_write (addr,
291 				  (void *) &ctrl->channels[c].current_c,
292 				  sizeof ctrl->channels[c].current_c);
293 }
294 
295 static void channel_store_d(struct fs_dma_ctrl *ctrl, int c)
296 {
297 	hwaddr addr = channel_reg(ctrl, c, RW_SAVED_DATA);
298 
299 	/* Encode and store. FIXME: handle endianness.  */
300 	D(printf("%s ch=%d addr=" TARGET_FMT_plx "\n", __func__, c, addr));
301 	cpu_physical_memory_write (addr,
302 				  (void *) &ctrl->channels[c].current_d,
303 				  sizeof ctrl->channels[c].current_d);
304 }
305 
306 static inline void channel_stop(struct fs_dma_ctrl *ctrl, int c)
307 {
308 	/* FIXME:  */
309 }
310 
311 static inline void channel_start(struct fs_dma_ctrl *ctrl, int c)
312 {
313 	if (ctrl->channels[c].client)
314 	{
315 		ctrl->channels[c].eol = 0;
316 		ctrl->channels[c].state = RUNNING;
317 		if (!ctrl->channels[c].input)
318 			channel_out_run(ctrl, c);
319 	} else
320 		printf("WARNING: starting DMA ch %d with no client\n", c);
321 
322         qemu_bh_schedule_idle(ctrl->bh);
323 }
324 
325 static void channel_continue(struct fs_dma_ctrl *ctrl, int c)
326 {
327 	if (!channel_en(ctrl, c)
328 	    || channel_stopped(ctrl, c)
329 	    || ctrl->channels[c].state != RUNNING
330 	    /* Only reload the current data descriptor if it has eol set.  */
331 	    || !ctrl->channels[c].current_d.eol) {
332 		D(printf("continue failed ch=%d state=%d stopped=%d en=%d eol=%d\n",
333 			 c, ctrl->channels[c].state,
334 			 channel_stopped(ctrl, c),
335 			 channel_en(ctrl,c),
336 			 ctrl->channels[c].eol));
337 		D(dump_d(c, &ctrl->channels[c].current_d));
338 		return;
339 	}
340 
341 	/* Reload the current descriptor.  */
342 	channel_load_d(ctrl, c);
343 
344 	/* If the current descriptor cleared the eol flag and we had already
345 	   reached eol state, do the continue.  */
346 	if (!ctrl->channels[c].current_d.eol && ctrl->channels[c].eol) {
347 		D(printf("continue %d ok %x\n", c,
348 			 ctrl->channels[c].current_d.next));
349 		ctrl->channels[c].regs[RW_SAVED_DATA] =
350 			(uint32_t)(unsigned long)ctrl->channels[c].current_d.next;
351 		channel_load_d(ctrl, c);
352 		ctrl->channels[c].regs[RW_SAVED_DATA_BUF] =
353 			(uint32_t)(unsigned long)ctrl->channels[c].current_d.buf;
354 
355 		channel_start(ctrl, c);
356 	}
357 	ctrl->channels[c].regs[RW_SAVED_DATA_BUF] =
358 		(uint32_t)(unsigned long)ctrl->channels[c].current_d.buf;
359 }
360 
361 static void channel_stream_cmd(struct fs_dma_ctrl *ctrl, int c, uint32_t v)
362 {
363 	unsigned int cmd = v & ((1 << 10) - 1);
364 
365 	D(printf("%s ch=%d cmd=%x\n",
366 		 __func__, c, cmd));
367 	if (cmd & regk_dma_load_d) {
368 		channel_load_d(ctrl, c);
369 		if (cmd & regk_dma_burst)
370 			channel_start(ctrl, c);
371 	}
372 
373 	if (cmd & regk_dma_load_c) {
374 		channel_load_c(ctrl, c);
375 	}
376 }
377 
378 static void channel_update_irq(struct fs_dma_ctrl *ctrl, int c)
379 {
380 	D(printf("%s %d\n", __func__, c));
381         ctrl->channels[c].regs[R_INTR] &=
382 		~(ctrl->channels[c].regs[RW_ACK_INTR]);
383 
384         ctrl->channels[c].regs[R_MASKED_INTR] =
385 		ctrl->channels[c].regs[R_INTR]
386 		& ctrl->channels[c].regs[RW_INTR_MASK];
387 
388 	D(printf("%s: chan=%d masked_intr=%x\n", __func__,
389 		 c,
390 		 ctrl->channels[c].regs[R_MASKED_INTR]));
391 
392         qemu_set_irq(ctrl->channels[c].irq,
393 		     !!ctrl->channels[c].regs[R_MASKED_INTR]);
394 }
395 
396 static int channel_out_run(struct fs_dma_ctrl *ctrl, int c)
397 {
398 	uint32_t len;
399 	uint32_t saved_data_buf;
400 	unsigned char buf[2 * 1024];
401 
402 	struct dma_context_metadata meta;
403 	bool send_context = true;
404 
405 	if (ctrl->channels[c].eol)
406 		return 0;
407 
408 	do {
409 		bool out_eop;
410 		D(printf("ch=%d buf=%x after=%x\n",
411 			 c,
412 			 (uint32_t)ctrl->channels[c].current_d.buf,
413 			 (uint32_t)ctrl->channels[c].current_d.after));
414 
415 		if (send_context) {
416 			if (ctrl->channels[c].client->client.metadata_push) {
417 				meta.metadata = ctrl->channels[c].current_d.md;
418 				ctrl->channels[c].client->client.metadata_push(
419 					ctrl->channels[c].client->client.opaque,
420 					&meta);
421 			}
422 			send_context = false;
423 		}
424 
425 		channel_load_d(ctrl, c);
426 		saved_data_buf = channel_reg(ctrl, c, RW_SAVED_DATA_BUF);
427 		len = (uint32_t)(unsigned long)
428 			ctrl->channels[c].current_d.after;
429 		len -= saved_data_buf;
430 
431 		if (len > sizeof buf)
432 			len = sizeof buf;
433 		cpu_physical_memory_read (saved_data_buf, buf, len);
434 
435 		out_eop = ((saved_data_buf + len) ==
436 		           ctrl->channels[c].current_d.after) &&
437 			ctrl->channels[c].current_d.out_eop;
438 
439 		D(printf("channel %d pushes %x %u bytes eop=%u\n", c,
440 		         saved_data_buf, len, out_eop));
441 
442 		if (ctrl->channels[c].client->client.push) {
443                         if (len > 0) {
444 				ctrl->channels[c].client->client.push(
445 					ctrl->channels[c].client->client.opaque,
446 					buf, len, out_eop);
447 			}
448 		} else {
449 			printf("WARNING: DMA ch%d dataloss,"
450 			       " no attached client.\n", c);
451 		}
452 
453 		saved_data_buf += len;
454 
455 		if (saved_data_buf == (uint32_t)(unsigned long)
456 				ctrl->channels[c].current_d.after) {
457 			/* Done. Step to next.  */
458 			if (ctrl->channels[c].current_d.out_eop) {
459 				send_context = true;
460 			}
461 			if (ctrl->channels[c].current_d.intr) {
462 				/* data intr.  */
463 				D(printf("signal intr %d eol=%d\n",
464 					len, ctrl->channels[c].current_d.eol));
465 				ctrl->channels[c].regs[R_INTR] |= (1 << 2);
466 				channel_update_irq(ctrl, c);
467 			}
468 			channel_store_d(ctrl, c);
469 			if (ctrl->channels[c].current_d.eol) {
470 				D(printf("channel %d EOL\n", c));
471 				ctrl->channels[c].eol = 1;
472 
473 				/* Mark the context as disabled.  */
474 				ctrl->channels[c].current_c.dis = 1;
475 				channel_store_c(ctrl, c);
476 
477 				channel_stop(ctrl, c);
478 			} else {
479 				ctrl->channels[c].regs[RW_SAVED_DATA] =
480 					(uint32_t)(unsigned long)ctrl->
481 						channels[c].current_d.next;
482 				/* Load new descriptor.  */
483 				channel_load_d(ctrl, c);
484 				saved_data_buf = (uint32_t)(unsigned long)
485 					ctrl->channels[c].current_d.buf;
486 			}
487 
488 			ctrl->channels[c].regs[RW_SAVED_DATA_BUF] =
489 							saved_data_buf;
490 			D(dump_d(c, &ctrl->channels[c].current_d));
491 		}
492 		ctrl->channels[c].regs[RW_SAVED_DATA_BUF] = saved_data_buf;
493 	} while (!ctrl->channels[c].eol);
494 	return 1;
495 }
496 
497 static int channel_in_process(struct fs_dma_ctrl *ctrl, int c,
498 			      unsigned char *buf, int buflen, int eop)
499 {
500 	uint32_t len;
501 	uint32_t saved_data_buf;
502 
503 	if (ctrl->channels[c].eol == 1)
504 		return 0;
505 
506 	channel_load_d(ctrl, c);
507 	saved_data_buf = channel_reg(ctrl, c, RW_SAVED_DATA_BUF);
508 	len = (uint32_t)(unsigned long)ctrl->channels[c].current_d.after;
509 	len -= saved_data_buf;
510 
511 	if (len > buflen)
512 		len = buflen;
513 
514 	cpu_physical_memory_write (saved_data_buf, buf, len);
515 	saved_data_buf += len;
516 
517 	if (saved_data_buf ==
518 	    (uint32_t)(unsigned long)ctrl->channels[c].current_d.after
519 	    || eop) {
520 		uint32_t r_intr = ctrl->channels[c].regs[R_INTR];
521 
522 		D(printf("in dscr end len=%d\n",
523 			 ctrl->channels[c].current_d.after
524 			 - ctrl->channels[c].current_d.buf));
525 		ctrl->channels[c].current_d.after = saved_data_buf;
526 
527 		/* Done. Step to next.  */
528 		if (ctrl->channels[c].current_d.intr) {
529 			/* TODO: signal eop to the client.  */
530 			/* data intr.  */
531 			ctrl->channels[c].regs[R_INTR] |= 3;
532 		}
533 		if (eop) {
534 			ctrl->channels[c].current_d.in_eop = 1;
535 			ctrl->channels[c].regs[R_INTR] |= 8;
536 		}
537 		if (r_intr != ctrl->channels[c].regs[R_INTR])
538 			channel_update_irq(ctrl, c);
539 
540 		channel_store_d(ctrl, c);
541 		D(dump_d(c, &ctrl->channels[c].current_d));
542 
543 		if (ctrl->channels[c].current_d.eol) {
544 			D(printf("channel %d EOL\n", c));
545 			ctrl->channels[c].eol = 1;
546 
547 			/* Mark the context as disabled.  */
548 			ctrl->channels[c].current_c.dis = 1;
549 			channel_store_c(ctrl, c);
550 
551 			channel_stop(ctrl, c);
552 		} else {
553 			ctrl->channels[c].regs[RW_SAVED_DATA] =
554 				(uint32_t)(unsigned long)ctrl->
555 					channels[c].current_d.next;
556 			/* Load new descriptor.  */
557 			channel_load_d(ctrl, c);
558 			saved_data_buf = (uint32_t)(unsigned long)
559 				ctrl->channels[c].current_d.buf;
560 		}
561 	}
562 
563 	ctrl->channels[c].regs[RW_SAVED_DATA_BUF] = saved_data_buf;
564 	return len;
565 }
566 
567 static inline int channel_in_run(struct fs_dma_ctrl *ctrl, int c)
568 {
569 	if (ctrl->channels[c].client->client.pull) {
570 		ctrl->channels[c].client->client.pull(
571 			ctrl->channels[c].client->client.opaque);
572 		return 1;
573 	} else
574 		return 0;
575 }
576 
577 static uint32_t dma_rinvalid (void *opaque, hwaddr addr)
578 {
579         hw_error("Unsupported short raccess. reg=" TARGET_FMT_plx "\n", addr);
580         return 0;
581 }
582 
583 static uint64_t
584 dma_read(void *opaque, hwaddr addr, unsigned int size)
585 {
586         struct fs_dma_ctrl *ctrl = opaque;
587 	int c;
588 	uint32_t r = 0;
589 
590 	if (size != 4) {
591 		dma_rinvalid(opaque, addr);
592 	}
593 
594 	/* Make addr relative to this channel and bounded to nr regs.  */
595 	c = fs_channel(addr);
596 	addr &= 0xff;
597 	addr >>= 2;
598 	switch (addr)
599 	{
600 		case RW_STAT:
601 			r = ctrl->channels[c].state & 7;
602 			r |= ctrl->channels[c].eol << 5;
603 			r |= ctrl->channels[c].stream_cmd_src << 8;
604 			break;
605 
606 		default:
607 			r = ctrl->channels[c].regs[addr];
608 			D(printf ("%s c=%d addr=" TARGET_FMT_plx "\n",
609 				  __func__, c, addr));
610 			break;
611 	}
612 	return r;
613 }
614 
615 static void
616 dma_winvalid (void *opaque, hwaddr addr, uint32_t value)
617 {
618         hw_error("Unsupported short waccess. reg=" TARGET_FMT_plx "\n", addr);
619 }
620 
621 static void
622 dma_update_state(struct fs_dma_ctrl *ctrl, int c)
623 {
624 	if (ctrl->channels[c].regs[RW_CFG] & 2)
625 		ctrl->channels[c].state = STOPPED;
626 	if (!(ctrl->channels[c].regs[RW_CFG] & 1))
627 		ctrl->channels[c].state = RST;
628 }
629 
630 static void
631 dma_write(void *opaque, hwaddr addr,
632 	  uint64_t val64, unsigned int size)
633 {
634         struct fs_dma_ctrl *ctrl = opaque;
635 	uint32_t value = val64;
636 	int c;
637 
638 	if (size != 4) {
639 		dma_winvalid(opaque, addr, value);
640 	}
641 
642         /* Make addr relative to this channel and bounded to nr regs.  */
643 	c = fs_channel(addr);
644         addr &= 0xff;
645         addr >>= 2;
646         switch (addr)
647 	{
648 		case RW_DATA:
649 			ctrl->channels[c].regs[addr] = value;
650 			break;
651 
652 		case RW_CFG:
653 			ctrl->channels[c].regs[addr] = value;
654 			dma_update_state(ctrl, c);
655 			break;
656 		case RW_CMD:
657 			/* continue.  */
658 			if (value & ~1)
659 				printf("Invalid store to ch=%d RW_CMD %x\n",
660 				       c, value);
661 			ctrl->channels[c].regs[addr] = value;
662 			channel_continue(ctrl, c);
663 			break;
664 
665 		case RW_SAVED_DATA:
666 		case RW_SAVED_DATA_BUF:
667 		case RW_GROUP:
668 		case RW_GROUP_DOWN:
669 			ctrl->channels[c].regs[addr] = value;
670 			break;
671 
672 		case RW_ACK_INTR:
673 		case RW_INTR_MASK:
674 			ctrl->channels[c].regs[addr] = value;
675 			channel_update_irq(ctrl, c);
676 			if (addr == RW_ACK_INTR)
677 				ctrl->channels[c].regs[RW_ACK_INTR] = 0;
678 			break;
679 
680 		case RW_STREAM_CMD:
681 			if (value & ~1023)
682 				printf("Invalid store to ch=%d "
683 				       "RW_STREAMCMD %x\n",
684 				       c, value);
685 			ctrl->channels[c].regs[addr] = value;
686 			D(printf("stream_cmd ch=%d\n", c));
687 			channel_stream_cmd(ctrl, c, value);
688 			break;
689 
690 	        default:
691 			D(printf ("%s c=%d " TARGET_FMT_plx "\n",
692 				__func__, c, addr));
693 			break;
694         }
695 }
696 
697 static const MemoryRegionOps dma_ops = {
698 	.read = dma_read,
699 	.write = dma_write,
700 	.endianness = DEVICE_NATIVE_ENDIAN,
701 	.valid = {
702 		.min_access_size = 1,
703 		.max_access_size = 4
704 	}
705 };
706 
707 static int etraxfs_dmac_run(void *opaque)
708 {
709 	struct fs_dma_ctrl *ctrl = opaque;
710 	int i;
711 	int p = 0;
712 
713 	for (i = 0;
714 	     i < ctrl->nr_channels;
715 	     i++)
716 	{
717 		if (ctrl->channels[i].state == RUNNING)
718 		{
719 			if (ctrl->channels[i].input) {
720 				p += channel_in_run(ctrl, i);
721 			} else {
722 				p += channel_out_run(ctrl, i);
723 			}
724 		}
725 	}
726 	return p;
727 }
728 
729 int etraxfs_dmac_input(struct etraxfs_dma_client *client,
730 		       void *buf, int len, int eop)
731 {
732 	return channel_in_process(client->ctrl, client->channel,
733 				  buf, len, eop);
734 }
735 
736 /* Connect an IRQ line with a channel.  */
737 void etraxfs_dmac_connect(void *opaque, int c, qemu_irq *line, int input)
738 {
739 	struct fs_dma_ctrl *ctrl = opaque;
740 	ctrl->channels[c].irq = *line;
741 	ctrl->channels[c].input = input;
742 }
743 
744 void etraxfs_dmac_connect_client(void *opaque, int c,
745 				 struct etraxfs_dma_client *cl)
746 {
747 	struct fs_dma_ctrl *ctrl = opaque;
748 	cl->ctrl = ctrl;
749 	cl->channel = c;
750 	ctrl->channels[c].client = cl;
751 }
752 
753 
754 static void DMA_run(void *opaque)
755 {
756     struct fs_dma_ctrl *etraxfs_dmac = opaque;
757     int p = 1;
758 
759     if (runstate_is_running())
760         p = etraxfs_dmac_run(etraxfs_dmac);
761 
762     if (p)
763         qemu_bh_schedule_idle(etraxfs_dmac->bh);
764 }
765 
766 void *etraxfs_dmac_init(hwaddr base, int nr_channels)
767 {
768 	struct fs_dma_ctrl *ctrl = NULL;
769 
770 	ctrl = g_malloc0(sizeof *ctrl);
771 
772         ctrl->bh = qemu_bh_new(DMA_run, ctrl);
773 
774 	ctrl->nr_channels = nr_channels;
775 	ctrl->channels = g_malloc0(sizeof ctrl->channels[0] * nr_channels);
776 
777 	memory_region_init_io(&ctrl->mmio, NULL, &dma_ops, ctrl, "etraxfs-dma",
778 			      nr_channels * 0x2000);
779 	memory_region_add_subregion(get_system_memory(), base, &ctrl->mmio);
780 
781 	return ctrl;
782 }
783