xref: /openbmc/qemu/hw/sd/pl181.c (revision bf957284)
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 "sysemu/block-backend.h"
11 #include "sysemu/blockdev.h"
12 #include "hw/sysbus.h"
13 #include "hw/sd.h"
14 
15 //#define DEBUG_PL181 1
16 
17 #ifdef DEBUG_PL181
18 #define DPRINTF(fmt, ...) \
19 do { printf("pl181: " fmt , ## __VA_ARGS__); } while (0)
20 #else
21 #define DPRINTF(fmt, ...) do {} while(0)
22 #endif
23 
24 #define PL181_FIFO_LEN 16
25 
26 #define TYPE_PL181 "pl181"
27 #define PL181(obj) OBJECT_CHECK(PL181State, (obj), TYPE_PL181)
28 
29 typedef struct PL181State {
30     SysBusDevice parent_obj;
31 
32     MemoryRegion iomem;
33     SDState *card;
34     uint32_t clock;
35     uint32_t power;
36     uint32_t cmdarg;
37     uint32_t cmd;
38     uint32_t datatimer;
39     uint32_t datalength;
40     uint32_t respcmd;
41     uint32_t response[4];
42     uint32_t datactrl;
43     uint32_t datacnt;
44     uint32_t status;
45     uint32_t mask[2];
46     int32_t fifo_pos;
47     int32_t fifo_len;
48     /* The linux 2.6.21 driver is buggy, and misbehaves if new data arrives
49        while it is reading the FIFO.  We hack around this by deferring
50        subsequent transfers until after the driver polls the status word.
51        http://www.arm.linux.org.uk/developer/patches/viewpatch.php?id=4446/1
52      */
53     int32_t linux_hack;
54     uint32_t fifo[PL181_FIFO_LEN];
55     qemu_irq irq[2];
56     /* GPIO outputs for 'card is readonly' and 'card inserted' */
57     qemu_irq cardstatus[2];
58 } PL181State;
59 
60 static const VMStateDescription vmstate_pl181 = {
61     .name = "pl181",
62     .version_id = 1,
63     .minimum_version_id = 1,
64     .fields = (VMStateField[]) {
65         VMSTATE_UINT32(clock, PL181State),
66         VMSTATE_UINT32(power, PL181State),
67         VMSTATE_UINT32(cmdarg, PL181State),
68         VMSTATE_UINT32(cmd, PL181State),
69         VMSTATE_UINT32(datatimer, PL181State),
70         VMSTATE_UINT32(datalength, PL181State),
71         VMSTATE_UINT32(respcmd, PL181State),
72         VMSTATE_UINT32_ARRAY(response, PL181State, 4),
73         VMSTATE_UINT32(datactrl, PL181State),
74         VMSTATE_UINT32(datacnt, PL181State),
75         VMSTATE_UINT32(status, PL181State),
76         VMSTATE_UINT32_ARRAY(mask, PL181State, 2),
77         VMSTATE_INT32(fifo_pos, PL181State),
78         VMSTATE_INT32(fifo_len, PL181State),
79         VMSTATE_INT32(linux_hack, PL181State),
80         VMSTATE_UINT32_ARRAY(fifo, PL181State, PL181_FIFO_LEN),
81         VMSTATE_END_OF_LIST()
82     }
83 };
84 
85 #define PL181_CMD_INDEX     0x3f
86 #define PL181_CMD_RESPONSE  (1 << 6)
87 #define PL181_CMD_LONGRESP  (1 << 7)
88 #define PL181_CMD_INTERRUPT (1 << 8)
89 #define PL181_CMD_PENDING   (1 << 9)
90 #define PL181_CMD_ENABLE    (1 << 10)
91 
92 #define PL181_DATA_ENABLE             (1 << 0)
93 #define PL181_DATA_DIRECTION          (1 << 1)
94 #define PL181_DATA_MODE               (1 << 2)
95 #define PL181_DATA_DMAENABLE          (1 << 3)
96 
97 #define PL181_STATUS_CMDCRCFAIL       (1 << 0)
98 #define PL181_STATUS_DATACRCFAIL      (1 << 1)
99 #define PL181_STATUS_CMDTIMEOUT       (1 << 2)
100 #define PL181_STATUS_DATATIMEOUT      (1 << 3)
101 #define PL181_STATUS_TXUNDERRUN       (1 << 4)
102 #define PL181_STATUS_RXOVERRUN        (1 << 5)
103 #define PL181_STATUS_CMDRESPEND       (1 << 6)
104 #define PL181_STATUS_CMDSENT          (1 << 7)
105 #define PL181_STATUS_DATAEND          (1 << 8)
106 #define PL181_STATUS_DATABLOCKEND     (1 << 10)
107 #define PL181_STATUS_CMDACTIVE        (1 << 11)
108 #define PL181_STATUS_TXACTIVE         (1 << 12)
109 #define PL181_STATUS_RXACTIVE         (1 << 13)
110 #define PL181_STATUS_TXFIFOHALFEMPTY  (1 << 14)
111 #define PL181_STATUS_RXFIFOHALFFULL   (1 << 15)
112 #define PL181_STATUS_TXFIFOFULL       (1 << 16)
113 #define PL181_STATUS_RXFIFOFULL       (1 << 17)
114 #define PL181_STATUS_TXFIFOEMPTY      (1 << 18)
115 #define PL181_STATUS_RXFIFOEMPTY      (1 << 19)
116 #define PL181_STATUS_TXDATAAVLBL      (1 << 20)
117 #define PL181_STATUS_RXDATAAVLBL      (1 << 21)
118 
119 #define PL181_STATUS_TX_FIFO (PL181_STATUS_TXACTIVE \
120                              |PL181_STATUS_TXFIFOHALFEMPTY \
121                              |PL181_STATUS_TXFIFOFULL \
122                              |PL181_STATUS_TXFIFOEMPTY \
123                              |PL181_STATUS_TXDATAAVLBL)
124 #define PL181_STATUS_RX_FIFO (PL181_STATUS_RXACTIVE \
125                              |PL181_STATUS_RXFIFOHALFFULL \
126                              |PL181_STATUS_RXFIFOFULL \
127                              |PL181_STATUS_RXFIFOEMPTY \
128                              |PL181_STATUS_RXDATAAVLBL)
129 
130 static const unsigned char pl181_id[] =
131 { 0x81, 0x11, 0x04, 0x00, 0x0d, 0xf0, 0x05, 0xb1 };
132 
133 static void pl181_update(PL181State *s)
134 {
135     int i;
136     for (i = 0; i < 2; i++) {
137         qemu_set_irq(s->irq[i], (s->status & s->mask[i]) != 0);
138     }
139 }
140 
141 static void pl181_fifo_push(PL181State *s, uint32_t value)
142 {
143     int n;
144 
145     if (s->fifo_len == PL181_FIFO_LEN) {
146         fprintf(stderr, "pl181: FIFO overflow\n");
147         return;
148     }
149     n = (s->fifo_pos + s->fifo_len) & (PL181_FIFO_LEN - 1);
150     s->fifo_len++;
151     s->fifo[n] = value;
152     DPRINTF("FIFO push %08x\n", (int)value);
153 }
154 
155 static uint32_t pl181_fifo_pop(PL181State *s)
156 {
157     uint32_t value;
158 
159     if (s->fifo_len == 0) {
160         fprintf(stderr, "pl181: FIFO underflow\n");
161         return 0;
162     }
163     value = s->fifo[s->fifo_pos];
164     s->fifo_len--;
165     s->fifo_pos = (s->fifo_pos + 1) & (PL181_FIFO_LEN - 1);
166     DPRINTF("FIFO pop %08x\n", (int)value);
167     return value;
168 }
169 
170 static void pl181_send_command(PL181State *s)
171 {
172     SDRequest request;
173     uint8_t response[16];
174     int rlen;
175 
176     request.cmd = s->cmd & PL181_CMD_INDEX;
177     request.arg = s->cmdarg;
178     DPRINTF("Command %d %08x\n", request.cmd, request.arg);
179     rlen = sd_do_command(s->card, &request, response);
180     if (rlen < 0)
181         goto error;
182     if (s->cmd & PL181_CMD_RESPONSE) {
183 #define RWORD(n) (((uint32_t)response[n] << 24) | (response[n + 1] << 16) \
184                   | (response[n + 2] << 8) | response[n + 3])
185         if (rlen == 0 || (rlen == 4 && (s->cmd & PL181_CMD_LONGRESP)))
186             goto error;
187         if (rlen != 4 && rlen != 16)
188             goto error;
189         s->response[0] = RWORD(0);
190         if (rlen == 4) {
191             s->response[1] = s->response[2] = s->response[3] = 0;
192         } else {
193             s->response[1] = RWORD(4);
194             s->response[2] = RWORD(8);
195             s->response[3] = RWORD(12) & ~1;
196         }
197         DPRINTF("Response received\n");
198         s->status |= PL181_STATUS_CMDRESPEND;
199 #undef RWORD
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 }
481 
482 static int pl181_init(SysBusDevice *sbd)
483 {
484     DeviceState *dev = DEVICE(sbd);
485     PL181State *s = PL181(dev);
486     DriveInfo *dinfo;
487 
488     memory_region_init_io(&s->iomem, OBJECT(s), &pl181_ops, s, "pl181", 0x1000);
489     sysbus_init_mmio(sbd, &s->iomem);
490     sysbus_init_irq(sbd, &s->irq[0]);
491     sysbus_init_irq(sbd, &s->irq[1]);
492     qdev_init_gpio_out(dev, s->cardstatus, 2);
493     /* FIXME use a qdev drive property instead of drive_get_next() */
494     dinfo = drive_get_next(IF_SD);
495     s->card = sd_init(dinfo ? blk_by_legacy_dinfo(dinfo) : NULL, false);
496     if (s->card == NULL) {
497         return -1;
498     }
499 
500     return 0;
501 }
502 
503 static void pl181_class_init(ObjectClass *klass, void *data)
504 {
505     SysBusDeviceClass *sdc = SYS_BUS_DEVICE_CLASS(klass);
506     DeviceClass *k = DEVICE_CLASS(klass);
507 
508     sdc->init = pl181_init;
509     k->vmsd = &vmstate_pl181;
510     k->reset = pl181_reset;
511     /* Reason: init() method uses drive_get_next() */
512     k->cannot_instantiate_with_device_add_yet = true;
513 }
514 
515 static const TypeInfo pl181_info = {
516     .name          = TYPE_PL181,
517     .parent        = TYPE_SYS_BUS_DEVICE,
518     .instance_size = sizeof(PL181State),
519     .class_init    = pl181_class_init,
520 };
521 
522 static void pl181_register_types(void)
523 {
524     type_register_static(&pl181_info);
525 }
526 
527 type_init(pl181_register_types)
528