2 * QEMU ETRAX DMA Controller.
4 * Copyright (c) 2008 Edgar E. Iglesias, Axis Communications AB.
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:
13 * The above copyright notice and this permission notice shall be included in
14 * all copies or substantial portions of the Software.
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
27 #include "qemu-common.h"
30 #include "etraxfs_dma.h"
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)
48 #define DMA_REG_MAX (0x100 / 4)
52 // ------------------------------------------------------------ dma_descr_group
53 typedef struct dma_descr_group
{
65 struct dma_descr_group
*up
;
67 struct dma_descr_context
*context
;
68 struct dma_descr_group
*group
;
72 // ---------------------------------------------------------- dma_descr_context
73 typedef struct dma_descr_context
{
79 unsigned store_mode
: 1;
89 uint32_t saved_data_buf
;
92 // ------------------------------------------------------------- dma_descr_data
93 typedef struct dma_descr_data
{
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
166 struct fs_dma_channel
169 struct etraxfs_dma_client
*client
;
171 /* Internal status. */
173 enum dma_ch_state state
;
175 unsigned int input
: 1;
176 unsigned int eol
: 1;
178 struct dma_descr_group current_g
;
179 struct dma_descr_context current_c
;
180 struct dma_descr_data current_d
;
182 /* Controll registers. */
183 uint32_t regs
[DMA_REG_MAX
];
190 struct fs_dma_channel
*channels
;
195 static void DMA_run(void *opaque
);
196 static int channel_out_run(struct fs_dma_ctrl
*ctrl
, int c
);
198 static inline uint32_t channel_reg(struct fs_dma_ctrl
*ctrl
, int c
, int reg
)
200 return ctrl
->channels
[c
].regs
[reg
];
203 static inline int channel_stopped(struct fs_dma_ctrl
*ctrl
, int c
)
205 return channel_reg(ctrl
, c
, RW_CFG
) & 2;
208 static inline int channel_en(struct fs_dma_ctrl
*ctrl
, int c
)
210 return (channel_reg(ctrl
, c
, RW_CFG
) & 1)
211 && ctrl
->channels
[c
].client
;
214 static inline int fs_channel(target_phys_addr_t addr
)
216 /* Every channel has a 0x2000 ctrl register map. */
220 #ifdef USE_THIS_DEAD_CODE
221 static void channel_load_g(struct fs_dma_ctrl
*ctrl
, int c
)
223 target_phys_addr_t addr
= channel_reg(ctrl
, c
, RW_GROUP
);
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
);
231 static void dump_c(int ch
, struct dma_descr_context
*c
)
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
);
240 static void dump_d(int ch
, struct dma_descr_data
*d
)
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
);
253 static void channel_load_c(struct fs_dma_ctrl
*ctrl
, int c
)
255 target_phys_addr_t addr
= channel_reg(ctrl
, c
, RW_GROUP_DOWN
);
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
);
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
;
270 static void channel_load_d(struct fs_dma_ctrl
*ctrl
, int c
)
272 target_phys_addr_t addr
= channel_reg(ctrl
, c
, RW_SAVED_DATA
);
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
);
280 D(dump_d(c
, &ctrl
->channels
[c
].current_d
));
281 ctrl
->channels
[c
].regs
[RW_DATA
] = addr
;
284 static void channel_store_c(struct fs_dma_ctrl
*ctrl
, int c
)
286 target_phys_addr_t addr
= channel_reg(ctrl
, c
, RW_GROUP_DOWN
);
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
);
296 static void channel_store_d(struct fs_dma_ctrl
*ctrl
, int c
)
298 target_phys_addr_t addr
= channel_reg(ctrl
, c
, RW_SAVED_DATA
);
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
);
307 static inline void channel_stop(struct fs_dma_ctrl
*ctrl
, int c
)
312 static inline void channel_start(struct fs_dma_ctrl
*ctrl
, int c
)
314 if (ctrl
->channels
[c
].client
)
316 ctrl
->channels
[c
].eol
= 0;
317 ctrl
->channels
[c
].state
= RUNNING
;
318 if (!ctrl
->channels
[c
].input
)
319 channel_out_run(ctrl
, c
);
321 printf("WARNING: starting DMA ch %d with no client\n", c
);
323 qemu_bh_schedule_idle(ctrl
->bh
);
326 static void channel_continue(struct fs_dma_ctrl
*ctrl
, int c
)
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
),
337 ctrl
->channels
[c
].eol
));
338 D(dump_d(c
, &ctrl
->channels
[c
].current_d
));
342 /* Reload the current descriptor. */
343 channel_load_d(ctrl
, c
);
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
;
356 channel_start(ctrl
, c
);
358 ctrl
->channels
[c
].regs
[RW_SAVED_DATA_BUF
] =
359 (uint32_t)(unsigned long)ctrl
->channels
[c
].current_d
.buf
;
362 static void channel_stream_cmd(struct fs_dma_ctrl
*ctrl
, int c
, uint32_t v
)
364 unsigned int cmd
= v
& ((1 << 10) - 1);
366 D(printf("%s ch=%d cmd=%x\n",
368 if (cmd
& regk_dma_load_d
) {
369 channel_load_d(ctrl
, c
);
370 if (cmd
& regk_dma_burst
)
371 channel_start(ctrl
, c
);
374 if (cmd
& regk_dma_load_c
) {
375 channel_load_c(ctrl
, c
);
379 static void channel_update_irq(struct fs_dma_ctrl
*ctrl
, int c
)
381 D(printf("%s %d\n", __func__
, c
));
382 ctrl
->channels
[c
].regs
[R_INTR
] &=
383 ~(ctrl
->channels
[c
].regs
[RW_ACK_INTR
]);
385 ctrl
->channels
[c
].regs
[R_MASKED_INTR
] =
386 ctrl
->channels
[c
].regs
[R_INTR
]
387 & ctrl
->channels
[c
].regs
[RW_INTR_MASK
];
389 D(printf("%s: chan=%d masked_intr=%x\n", __func__
,
391 ctrl
->channels
[c
].regs
[R_MASKED_INTR
]));
393 qemu_set_irq(ctrl
->channels
[c
].irq
,
394 !!ctrl
->channels
[c
].regs
[R_MASKED_INTR
]);
397 static int channel_out_run(struct fs_dma_ctrl
*ctrl
, int c
)
400 uint32_t saved_data_buf
;
401 unsigned char buf
[2 * 1024];
403 if (ctrl
->channels
[c
].eol
)
407 D(printf("ch=%d buf=%x after=%x\n",
409 (uint32_t)ctrl
->channels
[c
].current_d
.buf
,
410 (uint32_t)ctrl
->channels
[c
].current_d
.after
));
412 channel_load_d(ctrl
, c
);
413 saved_data_buf
= channel_reg(ctrl
, c
, RW_SAVED_DATA_BUF
);
414 len
= (uint32_t)(unsigned long)
415 ctrl
->channels
[c
].current_d
.after
;
416 len
-= saved_data_buf
;
418 if (len
> sizeof buf
)
420 cpu_physical_memory_read (saved_data_buf
, buf
, len
);
422 D(printf("channel %d pushes %x %u bytes\n", c
,
423 saved_data_buf
, len
));
425 if (ctrl
->channels
[c
].client
->client
.push
)
426 ctrl
->channels
[c
].client
->client
.push(
427 ctrl
->channels
[c
].client
->client
.opaque
,
430 printf("WARNING: DMA ch%d dataloss,"
431 " no attached client.\n", c
);
433 saved_data_buf
+= len
;
435 if (saved_data_buf
== (uint32_t)(unsigned long)
436 ctrl
->channels
[c
].current_d
.after
) {
437 /* Done. Step to next. */
438 if (ctrl
->channels
[c
].current_d
.out_eop
) {
439 /* TODO: signal eop to the client. */
440 D(printf("signal eop\n"));
442 if (ctrl
->channels
[c
].current_d
.intr
) {
443 /* TODO: signal eop to the client. */
445 D(printf("signal intr %d eol=%d\n",
446 len
, ctrl
->channels
[c
].current_d
.eol
));
447 ctrl
->channels
[c
].regs
[R_INTR
] |= (1 << 2);
448 channel_update_irq(ctrl
, c
);
450 channel_store_d(ctrl
, c
);
451 if (ctrl
->channels
[c
].current_d
.eol
) {
452 D(printf("channel %d EOL\n", c
));
453 ctrl
->channels
[c
].eol
= 1;
455 /* Mark the context as disabled. */
456 ctrl
->channels
[c
].current_c
.dis
= 1;
457 channel_store_c(ctrl
, c
);
459 channel_stop(ctrl
, c
);
461 ctrl
->channels
[c
].regs
[RW_SAVED_DATA
] =
462 (uint32_t)(unsigned long)ctrl
->
463 channels
[c
].current_d
.next
;
464 /* Load new descriptor. */
465 channel_load_d(ctrl
, c
);
466 saved_data_buf
= (uint32_t)(unsigned long)
467 ctrl
->channels
[c
].current_d
.buf
;
470 ctrl
->channels
[c
].regs
[RW_SAVED_DATA_BUF
] =
472 D(dump_d(c
, &ctrl
->channels
[c
].current_d
));
474 ctrl
->channels
[c
].regs
[RW_SAVED_DATA_BUF
] = saved_data_buf
;
475 } while (!ctrl
->channels
[c
].eol
);
479 static int channel_in_process(struct fs_dma_ctrl
*ctrl
, int c
,
480 unsigned char *buf
, int buflen
, int eop
)
483 uint32_t saved_data_buf
;
485 if (ctrl
->channels
[c
].eol
== 1)
488 channel_load_d(ctrl
, c
);
489 saved_data_buf
= channel_reg(ctrl
, c
, RW_SAVED_DATA_BUF
);
490 len
= (uint32_t)(unsigned long)ctrl
->channels
[c
].current_d
.after
;
491 len
-= saved_data_buf
;
496 cpu_physical_memory_write (saved_data_buf
, buf
, len
);
497 saved_data_buf
+= len
;
499 if (saved_data_buf
==
500 (uint32_t)(unsigned long)ctrl
->channels
[c
].current_d
.after
502 uint32_t r_intr
= ctrl
->channels
[c
].regs
[R_INTR
];
504 D(printf("in dscr end len=%d\n",
505 ctrl
->channels
[c
].current_d
.after
506 - ctrl
->channels
[c
].current_d
.buf
));
507 ctrl
->channels
[c
].current_d
.after
= saved_data_buf
;
509 /* Done. Step to next. */
510 if (ctrl
->channels
[c
].current_d
.intr
) {
511 /* TODO: signal eop to the client. */
513 ctrl
->channels
[c
].regs
[R_INTR
] |= 3;
516 ctrl
->channels
[c
].current_d
.in_eop
= 1;
517 ctrl
->channels
[c
].regs
[R_INTR
] |= 8;
519 if (r_intr
!= ctrl
->channels
[c
].regs
[R_INTR
])
520 channel_update_irq(ctrl
, c
);
522 channel_store_d(ctrl
, c
);
523 D(dump_d(c
, &ctrl
->channels
[c
].current_d
));
525 if (ctrl
->channels
[c
].current_d
.eol
) {
526 D(printf("channel %d EOL\n", c
));
527 ctrl
->channels
[c
].eol
= 1;
529 /* Mark the context as disabled. */
530 ctrl
->channels
[c
].current_c
.dis
= 1;
531 channel_store_c(ctrl
, c
);
533 channel_stop(ctrl
, c
);
535 ctrl
->channels
[c
].regs
[RW_SAVED_DATA
] =
536 (uint32_t)(unsigned long)ctrl
->
537 channels
[c
].current_d
.next
;
538 /* Load new descriptor. */
539 channel_load_d(ctrl
, c
);
540 saved_data_buf
= (uint32_t)(unsigned long)
541 ctrl
->channels
[c
].current_d
.buf
;
545 ctrl
->channels
[c
].regs
[RW_SAVED_DATA_BUF
] = saved_data_buf
;
549 static inline int channel_in_run(struct fs_dma_ctrl
*ctrl
, int c
)
551 if (ctrl
->channels
[c
].client
->client
.pull
) {
552 ctrl
->channels
[c
].client
->client
.pull(
553 ctrl
->channels
[c
].client
->client
.opaque
);
559 static uint32_t dma_rinvalid (void *opaque
, target_phys_addr_t addr
)
561 hw_error("Unsupported short raccess. reg=" TARGET_FMT_plx
"\n", addr
);
566 dma_readl (void *opaque
, target_phys_addr_t addr
)
568 struct fs_dma_ctrl
*ctrl
= opaque
;
572 /* Make addr relative to this channel and bounded to nr regs. */
573 c
= fs_channel(addr
);
579 r
= ctrl
->channels
[c
].state
& 7;
580 r
|= ctrl
->channels
[c
].eol
<< 5;
581 r
|= ctrl
->channels
[c
].stream_cmd_src
<< 8;
585 r
= ctrl
->channels
[c
].regs
[addr
];
586 D(printf ("%s c=%d addr=" TARGET_FMT_plx
"\n",
594 dma_winvalid (void *opaque
, target_phys_addr_t addr
, uint32_t value
)
596 hw_error("Unsupported short waccess. reg=" TARGET_FMT_plx
"\n", addr
);
600 dma_update_state(struct fs_dma_ctrl
*ctrl
, int c
)
602 if ((ctrl
->channels
[c
].regs
[RW_CFG
] & 1) != 3) {
603 if (ctrl
->channels
[c
].regs
[RW_CFG
] & 2)
604 ctrl
->channels
[c
].state
= STOPPED
;
605 if (!(ctrl
->channels
[c
].regs
[RW_CFG
] & 1))
606 ctrl
->channels
[c
].state
= RST
;
611 dma_writel (void *opaque
, target_phys_addr_t addr
, uint32_t value
)
613 struct fs_dma_ctrl
*ctrl
= opaque
;
616 /* Make addr relative to this channel and bounded to nr regs. */
617 c
= fs_channel(addr
);
623 ctrl
->channels
[c
].regs
[addr
] = value
;
627 ctrl
->channels
[c
].regs
[addr
] = value
;
628 dma_update_state(ctrl
, c
);
633 printf("Invalid store to ch=%d RW_CMD %x\n",
635 ctrl
->channels
[c
].regs
[addr
] = value
;
636 channel_continue(ctrl
, c
);
640 case RW_SAVED_DATA_BUF
:
643 ctrl
->channels
[c
].regs
[addr
] = value
;
648 ctrl
->channels
[c
].regs
[addr
] = value
;
649 channel_update_irq(ctrl
, c
);
650 if (addr
== RW_ACK_INTR
)
651 ctrl
->channels
[c
].regs
[RW_ACK_INTR
] = 0;
656 printf("Invalid store to ch=%d "
659 ctrl
->channels
[c
].regs
[addr
] = value
;
660 D(printf("stream_cmd ch=%d\n", c
));
661 channel_stream_cmd(ctrl
, c
, value
);
665 D(printf ("%s c=%d " TARGET_FMT_plx
"\n",
671 static CPUReadMemoryFunc
*dma_read
[] = {
677 static CPUWriteMemoryFunc
*dma_write
[] = {
683 static int etraxfs_dmac_run(void *opaque
)
685 struct fs_dma_ctrl
*ctrl
= opaque
;
690 i
< ctrl
->nr_channels
;
693 if (ctrl
->channels
[i
].state
== RUNNING
)
695 if (ctrl
->channels
[i
].input
) {
696 p
+= channel_in_run(ctrl
, i
);
698 p
+= channel_out_run(ctrl
, i
);
705 int etraxfs_dmac_input(struct etraxfs_dma_client
*client
,
706 void *buf
, int len
, int eop
)
708 return channel_in_process(client
->ctrl
, client
->channel
,
712 /* Connect an IRQ line with a channel. */
713 void etraxfs_dmac_connect(void *opaque
, int c
, qemu_irq
*line
, int input
)
715 struct fs_dma_ctrl
*ctrl
= opaque
;
716 ctrl
->channels
[c
].irq
= *line
;
717 ctrl
->channels
[c
].input
= input
;
720 void etraxfs_dmac_connect_client(void *opaque
, int c
,
721 struct etraxfs_dma_client
*cl
)
723 struct fs_dma_ctrl
*ctrl
= opaque
;
726 ctrl
->channels
[c
].client
= cl
;
730 static void DMA_run(void *opaque
)
732 struct fs_dma_ctrl
*etraxfs_dmac
= opaque
;
736 p
= etraxfs_dmac_run(etraxfs_dmac
);
739 qemu_bh_schedule_idle(etraxfs_dmac
->bh
);
742 void *etraxfs_dmac_init(target_phys_addr_t base
, int nr_channels
)
744 struct fs_dma_ctrl
*ctrl
= NULL
;
746 ctrl
= qemu_mallocz(sizeof *ctrl
);
748 ctrl
->bh
= qemu_bh_new(DMA_run
, ctrl
);
750 ctrl
->nr_channels
= nr_channels
;
751 ctrl
->channels
= qemu_mallocz(sizeof ctrl
->channels
[0] * nr_channels
);
753 ctrl
->map
= cpu_register_io_memory(dma_read
, dma_write
, ctrl
);
754 cpu_register_physical_memory(base
, nr_channels
* 0x2000, ctrl
->map
);