xref: /openbmc/qemu/hw/sd/pl181.c (revision 3d9569b8)
1 /*
2  * Arm PrimeCell PL181 MultiMedia Card Interface
3  *
4  * Copyright (c) 2007 CodeSourcery.
5  * Written by Paul Brook
6  *
7  * This code is licensed under the GPL.
8  */
9 
10 #include "qemu/osdep.h"
11 #include "sysemu/blockdev.h"
12 #include "hw/sysbus.h"
13 #include "hw/sd/sd.h"
14 #include "qemu/log.h"
15 #include "qemu/module.h"
16 #include "qapi/error.h"
17 
18 //#define DEBUG_PL181 1
19 
20 #ifdef DEBUG_PL181
21 #define DPRINTF(fmt, ...) \
22 do { printf("pl181: " fmt , ## __VA_ARGS__); } while (0)
23 #else
24 #define DPRINTF(fmt, ...) do {} while(0)
25 #endif
26 
27 #define PL181_FIFO_LEN 16
28 
29 #define TYPE_PL181 "pl181"
30 #define PL181(obj) OBJECT_CHECK(PL181State, (obj), TYPE_PL181)
31 
32 typedef struct PL181State {
33     SysBusDevice parent_obj;
34 
35     MemoryRegion iomem;
36     SDState *card;
37     uint32_t clock;
38     uint32_t power;
39     uint32_t cmdarg;
40     uint32_t cmd;
41     uint32_t datatimer;
42     uint32_t datalength;
43     uint32_t respcmd;
44     uint32_t response[4];
45     uint32_t datactrl;
46     uint32_t datacnt;
47     uint32_t status;
48     uint32_t mask[2];
49     int32_t fifo_pos;
50     int32_t fifo_len;
51     /* The linux 2.6.21 driver is buggy, and misbehaves if new data arrives
52        while it is reading the FIFO.  We hack around this by deferring
53        subsequent transfers until after the driver polls the status word.
54        http://www.arm.linux.org.uk/developer/patches/viewpatch.php?id=4446/1
55      */
56     int32_t linux_hack;
57     uint32_t fifo[PL181_FIFO_LEN];
58     qemu_irq irq[2];
59     /* GPIO outputs for 'card is readonly' and 'card inserted' */
60     qemu_irq cardstatus[2];
61 } PL181State;
62 
63 static const VMStateDescription vmstate_pl181 = {
64     .name = "pl181",
65     .version_id = 1,
66     .minimum_version_id = 1,
67     .fields = (VMStateField[]) {
68         VMSTATE_UINT32(clock, PL181State),
69         VMSTATE_UINT32(power, PL181State),
70         VMSTATE_UINT32(cmdarg, PL181State),
71         VMSTATE_UINT32(cmd, PL181State),
72         VMSTATE_UINT32(datatimer, PL181State),
73         VMSTATE_UINT32(datalength, PL181State),
74         VMSTATE_UINT32(respcmd, PL181State),
75         VMSTATE_UINT32_ARRAY(response, PL181State, 4),
76         VMSTATE_UINT32(datactrl, PL181State),
77         VMSTATE_UINT32(datacnt, PL181State),
78         VMSTATE_UINT32(status, PL181State),
79         VMSTATE_UINT32_ARRAY(mask, PL181State, 2),
80         VMSTATE_INT32(fifo_pos, PL181State),
81         VMSTATE_INT32(fifo_len, PL181State),
82         VMSTATE_INT32(linux_hack, PL181State),
83         VMSTATE_UINT32_ARRAY(fifo, PL181State, PL181_FIFO_LEN),
84         VMSTATE_END_OF_LIST()
85     }
86 };
87 
88 #define PL181_CMD_INDEX     0x3f
89 #define PL181_CMD_RESPONSE  (1 << 6)
90 #define PL181_CMD_LONGRESP  (1 << 7)
91 #define PL181_CMD_INTERRUPT (1 << 8)
92 #define PL181_CMD_PENDING   (1 << 9)
93 #define PL181_CMD_ENABLE    (1 << 10)
94 
95 #define PL181_DATA_ENABLE             (1 << 0)
96 #define PL181_DATA_DIRECTION          (1 << 1)
97 #define PL181_DATA_MODE               (1 << 2)
98 #define PL181_DATA_DMAENABLE          (1 << 3)
99 
100 #define PL181_STATUS_CMDCRCFAIL       (1 << 0)
101 #define PL181_STATUS_DATACRCFAIL      (1 << 1)
102 #define PL181_STATUS_CMDTIMEOUT       (1 << 2)
103 #define PL181_STATUS_DATATIMEOUT      (1 << 3)
104 #define PL181_STATUS_TXUNDERRUN       (1 << 4)
105 #define PL181_STATUS_RXOVERRUN        (1 << 5)
106 #define PL181_STATUS_CMDRESPEND       (1 << 6)
107 #define PL181_STATUS_CMDSENT          (1 << 7)
108 #define PL181_STATUS_DATAEND          (1 << 8)
109 #define PL181_STATUS_DATABLOCKEND     (1 << 10)
110 #define PL181_STATUS_CMDACTIVE        (1 << 11)
111 #define PL181_STATUS_TXACTIVE         (1 << 12)
112 #define PL181_STATUS_RXACTIVE         (1 << 13)
113 #define PL181_STATUS_TXFIFOHALFEMPTY  (1 << 14)
114 #define PL181_STATUS_RXFIFOHALFFULL   (1 << 15)
115 #define PL181_STATUS_TXFIFOFULL       (1 << 16)
116 #define PL181_STATUS_RXFIFOFULL       (1 << 17)
117 #define PL181_STATUS_TXFIFOEMPTY      (1 << 18)
118 #define PL181_STATUS_RXFIFOEMPTY      (1 << 19)
119 #define PL181_STATUS_TXDATAAVLBL      (1 << 20)
120 #define PL181_STATUS_RXDATAAVLBL      (1 << 21)
121 
122 #define PL181_STATUS_TX_FIFO (PL181_STATUS_TXACTIVE \
123                              |PL181_STATUS_TXFIFOHALFEMPTY \
124                              |PL181_STATUS_TXFIFOFULL \
125                              |PL181_STATUS_TXFIFOEMPTY \
126                              |PL181_STATUS_TXDATAAVLBL)
127 #define PL181_STATUS_RX_FIFO (PL181_STATUS_RXACTIVE \
128                              |PL181_STATUS_RXFIFOHALFFULL \
129                              |PL181_STATUS_RXFIFOFULL \
130                              |PL181_STATUS_RXFIFOEMPTY \
131                              |PL181_STATUS_RXDATAAVLBL)
132 
133 static const unsigned char pl181_id[] =
134 { 0x81, 0x11, 0x04, 0x00, 0x0d, 0xf0, 0x05, 0xb1 };
135 
136 static void pl181_update(PL181State *s)
137 {
138     int i;
139     for (i = 0; i < 2; i++) {
140         qemu_set_irq(s->irq[i], (s->status & s->mask[i]) != 0);
141     }
142 }
143 
144 static void pl181_fifo_push(PL181State *s, uint32_t value)
145 {
146     int n;
147 
148     if (s->fifo_len == PL181_FIFO_LEN) {
149         fprintf(stderr, "pl181: FIFO overflow\n");
150         return;
151     }
152     n = (s->fifo_pos + s->fifo_len) & (PL181_FIFO_LEN - 1);
153     s->fifo_len++;
154     s->fifo[n] = value;
155     DPRINTF("FIFO push %08x\n", (int)value);
156 }
157 
158 static uint32_t pl181_fifo_pop(PL181State *s)
159 {
160     uint32_t value;
161 
162     if (s->fifo_len == 0) {
163         fprintf(stderr, "pl181: FIFO underflow\n");
164         return 0;
165     }
166     value = s->fifo[s->fifo_pos];
167     s->fifo_len--;
168     s->fifo_pos = (s->fifo_pos + 1) & (PL181_FIFO_LEN - 1);
169     DPRINTF("FIFO pop %08x\n", (int)value);
170     return value;
171 }
172 
173 static void pl181_send_command(PL181State *s)
174 {
175     SDRequest request;
176     uint8_t response[16];
177     int rlen;
178 
179     request.cmd = s->cmd & PL181_CMD_INDEX;
180     request.arg = s->cmdarg;
181     DPRINTF("Command %d %08x\n", request.cmd, request.arg);
182     rlen = sd_do_command(s->card, &request, response);
183     if (rlen < 0)
184         goto error;
185     if (s->cmd & PL181_CMD_RESPONSE) {
186         if (rlen == 0 || (rlen == 4 && (s->cmd & PL181_CMD_LONGRESP)))
187             goto error;
188         if (rlen != 4 && rlen != 16)
189             goto error;
190         s->response[0] = ldl_be_p(&response[0]);
191         if (rlen == 4) {
192             s->response[1] = s->response[2] = s->response[3] = 0;
193         } else {
194             s->response[1] = ldl_be_p(&response[4]);
195             s->response[2] = ldl_be_p(&response[8]);
196             s->response[3] = ldl_be_p(&response[12]) & ~1;
197         }
198         DPRINTF("Response received\n");
199         s->status |= PL181_STATUS_CMDRESPEND;
200     } else {
201         DPRINTF("Command sent\n");
202         s->status |= PL181_STATUS_CMDSENT;
203     }
204     return;
205 
206 error:
207     DPRINTF("Timeout\n");
208     s->status |= PL181_STATUS_CMDTIMEOUT;
209 }
210 
211 /* Transfer data between the card and the FIFO.  This is complicated by
212    the FIFO holding 32-bit words and the card taking data in single byte
213    chunks.  FIFO bytes are transferred in little-endian order.  */
214 
215 static void pl181_fifo_run(PL181State *s)
216 {
217     uint32_t bits;
218     uint32_t value = 0;
219     int n;
220     int is_read;
221 
222     is_read = (s->datactrl & PL181_DATA_DIRECTION) != 0;
223     if (s->datacnt != 0 && (!is_read || sd_data_ready(s->card))
224             && !s->linux_hack) {
225         if (is_read) {
226             n = 0;
227             while (s->datacnt && s->fifo_len < PL181_FIFO_LEN) {
228                 value |= (uint32_t)sd_read_data(s->card) << (n * 8);
229                 s->datacnt--;
230                 n++;
231                 if (n == 4) {
232                     pl181_fifo_push(s, value);
233                     n = 0;
234                     value = 0;
235                 }
236             }
237             if (n != 0) {
238                 pl181_fifo_push(s, value);
239             }
240         } else { /* write */
241             n = 0;
242             while (s->datacnt > 0 && (s->fifo_len > 0 || n > 0)) {
243                 if (n == 0) {
244                     value = pl181_fifo_pop(s);
245                     n = 4;
246                 }
247                 n--;
248                 s->datacnt--;
249                 sd_write_data(s->card, value & 0xff);
250                 value >>= 8;
251             }
252         }
253     }
254     s->status &= ~(PL181_STATUS_RX_FIFO | PL181_STATUS_TX_FIFO);
255     if (s->datacnt == 0) {
256         s->status |= PL181_STATUS_DATAEND;
257         /* HACK: */
258         s->status |= PL181_STATUS_DATABLOCKEND;
259         DPRINTF("Transfer Complete\n");
260     }
261     if (s->datacnt == 0 && s->fifo_len == 0) {
262         s->datactrl &= ~PL181_DATA_ENABLE;
263         DPRINTF("Data engine idle\n");
264     } else {
265         /* Update FIFO bits.  */
266         bits = PL181_STATUS_TXACTIVE | PL181_STATUS_RXACTIVE;
267         if (s->fifo_len == 0) {
268             bits |= PL181_STATUS_TXFIFOEMPTY;
269             bits |= PL181_STATUS_RXFIFOEMPTY;
270         } else {
271             bits |= PL181_STATUS_TXDATAAVLBL;
272             bits |= PL181_STATUS_RXDATAAVLBL;
273         }
274         if (s->fifo_len == 16) {
275             bits |= PL181_STATUS_TXFIFOFULL;
276             bits |= PL181_STATUS_RXFIFOFULL;
277         }
278         if (s->fifo_len <= 8) {
279             bits |= PL181_STATUS_TXFIFOHALFEMPTY;
280         }
281         if (s->fifo_len >= 8) {
282             bits |= PL181_STATUS_RXFIFOHALFFULL;
283         }
284         if (s->datactrl & PL181_DATA_DIRECTION) {
285             bits &= PL181_STATUS_RX_FIFO;
286         } else {
287             bits &= PL181_STATUS_TX_FIFO;
288         }
289         s->status |= bits;
290     }
291 }
292 
293 static uint64_t pl181_read(void *opaque, hwaddr offset,
294                            unsigned size)
295 {
296     PL181State *s = (PL181State *)opaque;
297     uint32_t tmp;
298 
299     if (offset >= 0xfe0 && offset < 0x1000) {
300         return pl181_id[(offset - 0xfe0) >> 2];
301     }
302     switch (offset) {
303     case 0x00: /* Power */
304         return s->power;
305     case 0x04: /* Clock */
306         return s->clock;
307     case 0x08: /* Argument */
308         return s->cmdarg;
309     case 0x0c: /* Command */
310         return s->cmd;
311     case 0x10: /* RespCmd */
312         return s->respcmd;
313     case 0x14: /* Response0 */
314         return s->response[0];
315     case 0x18: /* Response1 */
316         return s->response[1];
317     case 0x1c: /* Response2 */
318         return s->response[2];
319     case 0x20: /* Response3 */
320         return s->response[3];
321     case 0x24: /* DataTimer */
322         return s->datatimer;
323     case 0x28: /* DataLength */
324         return s->datalength;
325     case 0x2c: /* DataCtrl */
326         return s->datactrl;
327     case 0x30: /* DataCnt */
328         return s->datacnt;
329     case 0x34: /* Status */
330         tmp = s->status;
331         if (s->linux_hack) {
332             s->linux_hack = 0;
333             pl181_fifo_run(s);
334             pl181_update(s);
335         }
336         return tmp;
337     case 0x3c: /* Mask0 */
338         return s->mask[0];
339     case 0x40: /* Mask1 */
340         return s->mask[1];
341     case 0x48: /* FifoCnt */
342         /* The documentation is somewhat vague about exactly what FifoCnt
343            does.  On real hardware it appears to be when decrememnted
344            when a word is transferred between the FIFO and the serial
345            data engine.  DataCnt is decremented after each byte is
346            transferred between the serial engine and the card.
347            We don't emulate this level of detail, so both can be the same.  */
348         tmp = (s->datacnt + 3) >> 2;
349         if (s->linux_hack) {
350             s->linux_hack = 0;
351             pl181_fifo_run(s);
352             pl181_update(s);
353         }
354         return tmp;
355     case 0x80: case 0x84: case 0x88: case 0x8c: /* FifoData */
356     case 0x90: case 0x94: case 0x98: case 0x9c:
357     case 0xa0: case 0xa4: case 0xa8: case 0xac:
358     case 0xb0: case 0xb4: case 0xb8: case 0xbc:
359         if (s->fifo_len == 0) {
360             qemu_log_mask(LOG_GUEST_ERROR, "pl181: Unexpected FIFO read\n");
361             return 0;
362         } else {
363             uint32_t value;
364             value = pl181_fifo_pop(s);
365             s->linux_hack = 1;
366             pl181_fifo_run(s);
367             pl181_update(s);
368             return value;
369         }
370     default:
371         qemu_log_mask(LOG_GUEST_ERROR,
372                       "pl181_read: Bad offset %x\n", (int)offset);
373         return 0;
374     }
375 }
376 
377 static void pl181_write(void *opaque, hwaddr offset,
378                         uint64_t value, unsigned size)
379 {
380     PL181State *s = (PL181State *)opaque;
381 
382     switch (offset) {
383     case 0x00: /* Power */
384         s->power = value & 0xff;
385         break;
386     case 0x04: /* Clock */
387         s->clock = value & 0xff;
388         break;
389     case 0x08: /* Argument */
390         s->cmdarg = value;
391         break;
392     case 0x0c: /* Command */
393         s->cmd = value;
394         if (s->cmd & PL181_CMD_ENABLE) {
395             if (s->cmd & PL181_CMD_INTERRUPT) {
396                 qemu_log_mask(LOG_UNIMP,
397                               "pl181: Interrupt mode not implemented\n");
398             } if (s->cmd & PL181_CMD_PENDING) {
399                 qemu_log_mask(LOG_UNIMP,
400                               "pl181: Pending commands not implemented\n");
401             } else {
402                 pl181_send_command(s);
403                 pl181_fifo_run(s);
404             }
405             /* The command has completed one way or the other.  */
406             s->cmd &= ~PL181_CMD_ENABLE;
407         }
408         break;
409     case 0x24: /* DataTimer */
410         s->datatimer = value;
411         break;
412     case 0x28: /* DataLength */
413         s->datalength = value & 0xffff;
414         break;
415     case 0x2c: /* DataCtrl */
416         s->datactrl = value & 0xff;
417         if (value & PL181_DATA_ENABLE) {
418             s->datacnt = s->datalength;
419             pl181_fifo_run(s);
420         }
421         break;
422     case 0x38: /* Clear */
423         s->status &= ~(value & 0x7ff);
424         break;
425     case 0x3c: /* Mask0 */
426         s->mask[0] = value;
427         break;
428     case 0x40: /* Mask1 */
429         s->mask[1] = value;
430         break;
431     case 0x80: case 0x84: case 0x88: case 0x8c: /* FifoData */
432     case 0x90: case 0x94: case 0x98: case 0x9c:
433     case 0xa0: case 0xa4: case 0xa8: case 0xac:
434     case 0xb0: case 0xb4: case 0xb8: case 0xbc:
435         if (s->datacnt == 0) {
436             qemu_log_mask(LOG_GUEST_ERROR, "pl181: Unexpected FIFO write\n");
437         } else {
438             pl181_fifo_push(s, value);
439             pl181_fifo_run(s);
440         }
441         break;
442     default:
443         qemu_log_mask(LOG_GUEST_ERROR,
444                       "pl181_write: Bad offset %x\n", (int)offset);
445     }
446     pl181_update(s);
447 }
448 
449 static const MemoryRegionOps pl181_ops = {
450     .read = pl181_read,
451     .write = pl181_write,
452     .endianness = DEVICE_NATIVE_ENDIAN,
453 };
454 
455 static void pl181_reset(DeviceState *d)
456 {
457     PL181State *s = PL181(d);
458 
459     s->power = 0;
460     s->cmdarg = 0;
461     s->cmd = 0;
462     s->datatimer = 0;
463     s->datalength = 0;
464     s->respcmd = 0;
465     s->response[0] = 0;
466     s->response[1] = 0;
467     s->response[2] = 0;
468     s->response[3] = 0;
469     s->datatimer = 0;
470     s->datalength = 0;
471     s->datactrl = 0;
472     s->datacnt = 0;
473     s->status = 0;
474     s->linux_hack = 0;
475     s->mask[0] = 0;
476     s->mask[1] = 0;
477 
478     /* We can assume our GPIO outputs have been wired up now */
479     sd_set_cb(s->card, s->cardstatus[0], s->cardstatus[1]);
480     /* Since we're still using the legacy SD API the card is not plugged
481      * into any bus, and we must reset it manually.
482      */
483     device_reset(DEVICE(s->card));
484 }
485 
486 static void pl181_init(Object *obj)
487 {
488     DeviceState *dev = DEVICE(obj);
489     PL181State *s = PL181(obj);
490     SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
491 
492     memory_region_init_io(&s->iomem, obj, &pl181_ops, s, "pl181", 0x1000);
493     sysbus_init_mmio(sbd, &s->iomem);
494     sysbus_init_irq(sbd, &s->irq[0]);
495     sysbus_init_irq(sbd, &s->irq[1]);
496     qdev_init_gpio_out(dev, s->cardstatus, 2);
497 }
498 
499 static void pl181_realize(DeviceState *dev, Error **errp)
500 {
501     PL181State *s = PL181(dev);
502     DriveInfo *dinfo;
503 
504     /* FIXME use a qdev drive property instead of drive_get_next() */
505     dinfo = drive_get_next(IF_SD);
506     s->card = sd_init(dinfo ? blk_by_legacy_dinfo(dinfo) : NULL, false);
507     if (s->card == NULL) {
508         error_setg(errp, "sd_init failed");
509     }
510 }
511 
512 static void pl181_class_init(ObjectClass *klass, void *data)
513 {
514     DeviceClass *k = DEVICE_CLASS(klass);
515 
516     k->vmsd = &vmstate_pl181;
517     k->reset = pl181_reset;
518     /* Reason: init() method uses drive_get_next() */
519     k->user_creatable = false;
520     k->realize = pl181_realize;
521 }
522 
523 static const TypeInfo pl181_info = {
524     .name          = TYPE_PL181,
525     .parent        = TYPE_SYS_BUS_DEVICE,
526     .instance_size = sizeof(PL181State),
527     .instance_init = pl181_init,
528     .class_init    = pl181_class_init,
529 };
530 
531 static void pl181_register_types(void)
532 {
533     type_register_static(&pl181_info);
534 }
535 
536 type_init(pl181_register_types)
537