Introduce a Python module structure
[qemu/ar7.git] / hw / dma / bcm2835_dma.c
blob5d144a263324d37a4312dff47224c7d5c22da757
1 /*
2 * Raspberry Pi emulation (c) 2012 Gregory Estrade
3 * This code is licensed under the GNU GPLv2 and later.
4 */
6 #include "qemu/osdep.h"
7 #include "qapi/error.h"
8 #include "hw/dma/bcm2835_dma.h"
9 #include "qemu/log.h"
11 /* DMA CS Control and Status bits */
12 #define BCM2708_DMA_ACTIVE (1 << 0)
13 #define BCM2708_DMA_END (1 << 1) /* GE */
14 #define BCM2708_DMA_INT (1 << 2)
15 #define BCM2708_DMA_ISPAUSED (1 << 4) /* Pause requested or not active */
16 #define BCM2708_DMA_ISHELD (1 << 5) /* Is held by DREQ flow control */
17 #define BCM2708_DMA_ERR (1 << 8)
18 #define BCM2708_DMA_ABORT (1 << 30) /* stop current CB, go to next, WO */
19 #define BCM2708_DMA_RESET (1 << 31) /* WO, self clearing */
21 /* DMA control block "info" field bits */
22 #define BCM2708_DMA_INT_EN (1 << 0)
23 #define BCM2708_DMA_TDMODE (1 << 1)
24 #define BCM2708_DMA_WAIT_RESP (1 << 3)
25 #define BCM2708_DMA_D_INC (1 << 4)
26 #define BCM2708_DMA_D_WIDTH (1 << 5)
27 #define BCM2708_DMA_D_DREQ (1 << 6)
28 #define BCM2708_DMA_D_IGNORE (1 << 7)
29 #define BCM2708_DMA_S_INC (1 << 8)
30 #define BCM2708_DMA_S_WIDTH (1 << 9)
31 #define BCM2708_DMA_S_DREQ (1 << 10)
32 #define BCM2708_DMA_S_IGNORE (1 << 11)
34 /* Register offsets */
35 #define BCM2708_DMA_CS 0x00 /* Control and Status */
36 #define BCM2708_DMA_ADDR 0x04 /* Control block address */
37 /* the current control block appears in the following registers - read only */
38 #define BCM2708_DMA_INFO 0x08
39 #define BCM2708_DMA_SOURCE_AD 0x0c
40 #define BCM2708_DMA_DEST_AD 0x10
41 #define BCM2708_DMA_TXFR_LEN 0x14
42 #define BCM2708_DMA_STRIDE 0x18
43 #define BCM2708_DMA_NEXTCB 0x1C
44 #define BCM2708_DMA_DEBUG 0x20
46 #define BCM2708_DMA_INT_STATUS 0xfe0 /* Interrupt status of each channel */
47 #define BCM2708_DMA_ENABLE 0xff0 /* Global enable bits for each channel */
49 #define BCM2708_DMA_CS_RW_MASK 0x30ff0001 /* All RW bits in DMA_CS */
51 static void bcm2835_dma_update(BCM2835DMAState *s, unsigned c)
53 BCM2835DMAChan *ch = &s->chan[c];
54 uint32_t data, xlen, ylen;
55 int16_t dst_stride, src_stride;
57 if (!(s->enable & (1 << c))) {
58 return;
61 while ((s->enable & (1 << c)) && (ch->conblk_ad != 0)) {
62 /* CB fetch */
63 ch->ti = ldl_le_phys(&s->dma_as, ch->conblk_ad);
64 ch->source_ad = ldl_le_phys(&s->dma_as, ch->conblk_ad + 4);
65 ch->dest_ad = ldl_le_phys(&s->dma_as, ch->conblk_ad + 8);
66 ch->txfr_len = ldl_le_phys(&s->dma_as, ch->conblk_ad + 12);
67 ch->stride = ldl_le_phys(&s->dma_as, ch->conblk_ad + 16);
68 ch->nextconbk = ldl_le_phys(&s->dma_as, ch->conblk_ad + 20);
70 if (ch->ti & BCM2708_DMA_TDMODE) {
71 /* 2D transfer mode */
72 ylen = (ch->txfr_len >> 16) & 0x3fff;
73 xlen = ch->txfr_len & 0xffff;
74 dst_stride = ch->stride >> 16;
75 src_stride = ch->stride & 0xffff;
76 } else {
77 ylen = 1;
78 xlen = ch->txfr_len;
79 dst_stride = 0;
80 src_stride = 0;
83 while (ylen != 0) {
84 /* Normal transfer mode */
85 while (xlen != 0) {
86 if (ch->ti & BCM2708_DMA_S_IGNORE) {
87 /* Ignore reads */
88 data = 0;
89 } else {
90 data = ldl_le_phys(&s->dma_as, ch->source_ad);
92 if (ch->ti & BCM2708_DMA_S_INC) {
93 ch->source_ad += 4;
96 if (ch->ti & BCM2708_DMA_D_IGNORE) {
97 /* Ignore writes */
98 } else {
99 stl_le_phys(&s->dma_as, ch->dest_ad, data);
101 if (ch->ti & BCM2708_DMA_D_INC) {
102 ch->dest_ad += 4;
105 /* update remaining transfer length */
106 xlen -= 4;
107 if (ch->ti & BCM2708_DMA_TDMODE) {
108 ch->txfr_len = (ylen << 16) | xlen;
109 } else {
110 ch->txfr_len = xlen;
114 if (--ylen != 0) {
115 ch->source_ad += src_stride;
116 ch->dest_ad += dst_stride;
119 ch->cs |= BCM2708_DMA_END;
120 if (ch->ti & BCM2708_DMA_INT_EN) {
121 ch->cs |= BCM2708_DMA_INT;
122 s->int_status |= (1 << c);
123 qemu_set_irq(ch->irq, 1);
126 /* Process next CB */
127 ch->conblk_ad = ch->nextconbk;
130 ch->cs &= ~BCM2708_DMA_ACTIVE;
131 ch->cs |= BCM2708_DMA_ISPAUSED;
134 static void bcm2835_dma_chan_reset(BCM2835DMAChan *ch)
136 ch->cs = 0;
137 ch->conblk_ad = 0;
140 static uint64_t bcm2835_dma_read(BCM2835DMAState *s, hwaddr offset,
141 unsigned size, unsigned c)
143 BCM2835DMAChan *ch;
144 uint32_t res = 0;
146 assert(size == 4);
147 assert(c < BCM2835_DMA_NCHANS);
149 ch = &s->chan[c];
151 switch (offset) {
152 case BCM2708_DMA_CS:
153 res = ch->cs;
154 break;
155 case BCM2708_DMA_ADDR:
156 res = ch->conblk_ad;
157 break;
158 case BCM2708_DMA_INFO:
159 res = ch->ti;
160 break;
161 case BCM2708_DMA_SOURCE_AD:
162 res = ch->source_ad;
163 break;
164 case BCM2708_DMA_DEST_AD:
165 res = ch->dest_ad;
166 break;
167 case BCM2708_DMA_TXFR_LEN:
168 res = ch->txfr_len;
169 break;
170 case BCM2708_DMA_STRIDE:
171 res = ch->stride;
172 break;
173 case BCM2708_DMA_NEXTCB:
174 res = ch->nextconbk;
175 break;
176 case BCM2708_DMA_DEBUG:
177 res = ch->debug;
178 break;
179 default:
180 qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad offset %"HWADDR_PRIx"\n",
181 __func__, offset);
182 break;
184 return res;
187 static void bcm2835_dma_write(BCM2835DMAState *s, hwaddr offset,
188 uint64_t value, unsigned size, unsigned c)
190 BCM2835DMAChan *ch;
191 uint32_t oldcs;
193 assert(size == 4);
194 assert(c < BCM2835_DMA_NCHANS);
196 ch = &s->chan[c];
198 switch (offset) {
199 case BCM2708_DMA_CS:
200 oldcs = ch->cs;
201 if (value & BCM2708_DMA_RESET) {
202 bcm2835_dma_chan_reset(ch);
204 if (value & BCM2708_DMA_ABORT) {
205 /* abort is a no-op, since we always run to completion */
207 if (value & BCM2708_DMA_END) {
208 ch->cs &= ~BCM2708_DMA_END;
210 if (value & BCM2708_DMA_INT) {
211 ch->cs &= ~BCM2708_DMA_INT;
212 s->int_status &= ~(1 << c);
213 qemu_set_irq(ch->irq, 0);
215 ch->cs &= ~BCM2708_DMA_CS_RW_MASK;
216 ch->cs |= (value & BCM2708_DMA_CS_RW_MASK);
217 if (!(oldcs & BCM2708_DMA_ACTIVE) && (ch->cs & BCM2708_DMA_ACTIVE)) {
218 bcm2835_dma_update(s, c);
220 break;
221 case BCM2708_DMA_ADDR:
222 ch->conblk_ad = value;
223 break;
224 case BCM2708_DMA_DEBUG:
225 ch->debug = value;
226 break;
227 default:
228 qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad offset %"HWADDR_PRIx"\n",
229 __func__, offset);
230 break;
234 static uint64_t bcm2835_dma0_read(void *opaque, hwaddr offset, unsigned size)
236 BCM2835DMAState *s = opaque;
238 if (offset < 0xf00) {
239 return bcm2835_dma_read(s, (offset & 0xff), size, (offset >> 8) & 0xf);
240 } else {
241 switch (offset) {
242 case BCM2708_DMA_INT_STATUS:
243 return s->int_status;
244 case BCM2708_DMA_ENABLE:
245 return s->enable;
246 default:
247 qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad offset %"HWADDR_PRIx"\n",
248 __func__, offset);
249 return 0;
254 static uint64_t bcm2835_dma15_read(void *opaque, hwaddr offset, unsigned size)
256 return bcm2835_dma_read(opaque, (offset & 0xff), size, 15);
259 static void bcm2835_dma0_write(void *opaque, hwaddr offset, uint64_t value,
260 unsigned size)
262 BCM2835DMAState *s = opaque;
264 if (offset < 0xf00) {
265 bcm2835_dma_write(s, (offset & 0xff), value, size, (offset >> 8) & 0xf);
266 } else {
267 switch (offset) {
268 case BCM2708_DMA_INT_STATUS:
269 break;
270 case BCM2708_DMA_ENABLE:
271 s->enable = (value & 0xffff);
272 break;
273 default:
274 qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad offset %"HWADDR_PRIx"\n",
275 __func__, offset);
281 static void bcm2835_dma15_write(void *opaque, hwaddr offset, uint64_t value,
282 unsigned size)
284 bcm2835_dma_write(opaque, (offset & 0xff), value, size, 15);
287 static const MemoryRegionOps bcm2835_dma0_ops = {
288 .read = bcm2835_dma0_read,
289 .write = bcm2835_dma0_write,
290 .endianness = DEVICE_NATIVE_ENDIAN,
291 .valid.min_access_size = 4,
292 .valid.max_access_size = 4,
295 static const MemoryRegionOps bcm2835_dma15_ops = {
296 .read = bcm2835_dma15_read,
297 .write = bcm2835_dma15_write,
298 .endianness = DEVICE_NATIVE_ENDIAN,
299 .valid.min_access_size = 4,
300 .valid.max_access_size = 4,
303 static const VMStateDescription vmstate_bcm2835_dma_chan = {
304 .name = TYPE_BCM2835_DMA "-chan",
305 .version_id = 1,
306 .minimum_version_id = 1,
307 .fields = (VMStateField[]) {
308 VMSTATE_UINT32(cs, BCM2835DMAChan),
309 VMSTATE_UINT32(conblk_ad, BCM2835DMAChan),
310 VMSTATE_UINT32(ti, BCM2835DMAChan),
311 VMSTATE_UINT32(source_ad, BCM2835DMAChan),
312 VMSTATE_UINT32(dest_ad, BCM2835DMAChan),
313 VMSTATE_UINT32(txfr_len, BCM2835DMAChan),
314 VMSTATE_UINT32(stride, BCM2835DMAChan),
315 VMSTATE_UINT32(nextconbk, BCM2835DMAChan),
316 VMSTATE_UINT32(debug, BCM2835DMAChan),
317 VMSTATE_END_OF_LIST()
321 static const VMStateDescription vmstate_bcm2835_dma = {
322 .name = TYPE_BCM2835_DMA,
323 .version_id = 1,
324 .minimum_version_id = 1,
325 .fields = (VMStateField[]) {
326 VMSTATE_STRUCT_ARRAY(chan, BCM2835DMAState, BCM2835_DMA_NCHANS, 1,
327 vmstate_bcm2835_dma_chan, BCM2835DMAChan),
328 VMSTATE_UINT32(int_status, BCM2835DMAState),
329 VMSTATE_UINT32(enable, BCM2835DMAState),
330 VMSTATE_END_OF_LIST()
334 static void bcm2835_dma_init(Object *obj)
336 BCM2835DMAState *s = BCM2835_DMA(obj);
337 int n;
339 /* DMA channels 0-14 occupy a contiguous block of IO memory, along
340 * with the global enable and interrupt status bits. Channel 15
341 * has the same register map, but is mapped at a discontiguous
342 * address in a separate IO block.
344 memory_region_init_io(&s->iomem0, OBJECT(s), &bcm2835_dma0_ops, s,
345 TYPE_BCM2835_DMA, 0x1000);
346 sysbus_init_mmio(SYS_BUS_DEVICE(s), &s->iomem0);
348 memory_region_init_io(&s->iomem15, OBJECT(s), &bcm2835_dma15_ops, s,
349 TYPE_BCM2835_DMA "-chan15", 0x100);
350 sysbus_init_mmio(SYS_BUS_DEVICE(s), &s->iomem15);
352 for (n = 0; n < 16; n++) {
353 sysbus_init_irq(SYS_BUS_DEVICE(s), &s->chan[n].irq);
357 static void bcm2835_dma_reset(DeviceState *dev)
359 BCM2835DMAState *s = BCM2835_DMA(dev);
360 int n;
362 s->enable = 0xffff;
363 s->int_status = 0;
364 for (n = 0; n < BCM2835_DMA_NCHANS; n++) {
365 bcm2835_dma_chan_reset(&s->chan[n]);
369 static void bcm2835_dma_realize(DeviceState *dev, Error **errp)
371 BCM2835DMAState *s = BCM2835_DMA(dev);
372 Error *err = NULL;
373 Object *obj;
375 obj = object_property_get_link(OBJECT(dev), "dma-mr", &err);
376 if (obj == NULL) {
377 error_setg(errp, "%s: required dma-mr link not found: %s",
378 __func__, error_get_pretty(err));
379 return;
382 s->dma_mr = MEMORY_REGION(obj);
383 address_space_init(&s->dma_as, s->dma_mr, NULL);
385 bcm2835_dma_reset(dev);
388 static void bcm2835_dma_class_init(ObjectClass *klass, void *data)
390 DeviceClass *dc = DEVICE_CLASS(klass);
392 dc->realize = bcm2835_dma_realize;
393 dc->reset = bcm2835_dma_reset;
394 dc->vmsd = &vmstate_bcm2835_dma;
397 static TypeInfo bcm2835_dma_info = {
398 .name = TYPE_BCM2835_DMA,
399 .parent = TYPE_SYS_BUS_DEVICE,
400 .instance_size = sizeof(BCM2835DMAState),
401 .class_init = bcm2835_dma_class_init,
402 .instance_init = bcm2835_dma_init,
405 static void bcm2835_dma_register_types(void)
407 type_register_static(&bcm2835_dma_info);
410 type_init(bcm2835_dma_register_types)