xref: /qemu/hw/sd/sdhci.c (revision da34692234a03b6ffabd0b5b7864b423ac8eca56)
1 /*
2  * SD Association Host Standard Specification v2.0 controller emulation
3  *
4  * Copyright (c) 2011 Samsung Electronics Co., Ltd.
5  * Mitsyanko Igor <i.mitsyanko@samsung.com>
6  * Peter A.G. Crosthwaite <peter.crosthwaite@petalogix.com>
7  *
8  * Based on MMC controller for Samsung S5PC1xx-based board emulation
9  * by Alexey Merkulov and Vladimir Monakhov.
10  *
11  * This program is free software; you can redistribute it and/or modify it
12  * under the terms of the GNU General Public License as published by the
13  * Free Software Foundation; either version 2 of the License, or (at your
14  * option) any later version.
15  *
16  * This program is distributed in the hope that it will be useful,
17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
19  * See the GNU General Public License for more details.
20  *
21  * You should have received a copy of the GNU General Public License along
22  * with this program; if not, see <http://www.gnu.org/licenses/>.
23  */
24 
25 #include "qemu/osdep.h"
26 #include "qemu/error-report.h"
27 #include "qapi/error.h"
28 #include "hw/hw.h"
29 #include "sysemu/block-backend.h"
30 #include "sysemu/blockdev.h"
31 #include "sysemu/dma.h"
32 #include "qemu/timer.h"
33 #include "qemu/bitops.h"
34 #include "hw/sd/sdhci.h"
35 #include "sdhci-internal.h"
36 #include "qemu/log.h"
37 #include "qemu/cutils.h"
38 #include "trace.h"
39 
40 #define TYPE_SDHCI_BUS "sdhci-bus"
41 #define SDHCI_BUS(obj) OBJECT_CHECK(SDBus, (obj), TYPE_SDHCI_BUS)
42 
43 #define MASKED_WRITE(reg, mask, val)  (reg = (reg & (mask)) | (val))
44 
45 /* Default SD/MMC host controller features information, which will be
46  * presented in CAPABILITIES register of generic SD host controller at reset.
47  *
48  * support:
49  * - 3.3v and 1.8v voltages
50  * - SDMA/ADMA1/ADMA2
51  * - high-speed
52  * max host controller R/W buffers size: 512B
53  * max clock frequency for SDclock: 52 MHz
54  * timeout clock frequency: 52 MHz
55  *
56  * does not support:
57  * - 3.0v voltage
58  * - 64-bit system bus
59  * - suspend/resume
60  */
61 #define SDHC_CAPAB_REG_DEFAULT 0x057834b4
62 
63 static inline unsigned int sdhci_get_fifolen(SDHCIState *s)
64 {
65     return 1 << (9 + FIELD_EX32(s->capareg, SDHC_CAPAB, MAXBLOCKLENGTH));
66 }
67 
68 /* return true on error */
69 static bool sdhci_check_capab_freq_range(SDHCIState *s, const char *desc,
70                                          uint8_t freq, Error **errp)
71 {
72     if (s->sd_spec_version >= 3) {
73         return false;
74     }
75     switch (freq) {
76     case 0:
77     case 10 ... 63:
78         break;
79     default:
80         error_setg(errp, "SD %s clock frequency can have value"
81                    "in range 0-63 only", desc);
82         return true;
83     }
84     return false;
85 }
86 
87 static void sdhci_check_capareg(SDHCIState *s, Error **errp)
88 {
89     uint64_t msk = s->capareg;
90     uint32_t val;
91     bool y;
92 
93     switch (s->sd_spec_version) {
94     case 3:
95         val = FIELD_EX64(s->capareg, SDHC_CAPAB, ASYNC_INT);
96         trace_sdhci_capareg("async interrupt", val);
97         msk = FIELD_DP64(msk, SDHC_CAPAB, ASYNC_INT, 0);
98 
99         val = FIELD_EX64(s->capareg, SDHC_CAPAB, SLOT_TYPE);
100         if (val) {
101             error_setg(errp, "slot-type not supported");
102             return;
103         }
104         trace_sdhci_capareg("slot type", val);
105         msk = FIELD_DP64(msk, SDHC_CAPAB, SLOT_TYPE, 0);
106 
107         if (val != 2) {
108             val = FIELD_EX64(s->capareg, SDHC_CAPAB, EMBEDDED_8BIT);
109             trace_sdhci_capareg("8-bit bus", val);
110         }
111         msk = FIELD_DP64(msk, SDHC_CAPAB, EMBEDDED_8BIT, 0);
112 
113         val = FIELD_EX64(s->capareg, SDHC_CAPAB, BUS_SPEED);
114         trace_sdhci_capareg("bus speed mask", val);
115         msk = FIELD_DP64(msk, SDHC_CAPAB, BUS_SPEED, 0);
116 
117         val = FIELD_EX64(s->capareg, SDHC_CAPAB, DRIVER_STRENGTH);
118         trace_sdhci_capareg("driver strength mask", val);
119         msk = FIELD_DP64(msk, SDHC_CAPAB, DRIVER_STRENGTH, 0);
120 
121         val = FIELD_EX64(s->capareg, SDHC_CAPAB, TIMER_RETUNING);
122         trace_sdhci_capareg("timer re-tuning", val);
123         msk = FIELD_DP64(msk, SDHC_CAPAB, TIMER_RETUNING, 0);
124 
125         val = FIELD_EX64(s->capareg, SDHC_CAPAB, SDR50_TUNING);
126         trace_sdhci_capareg("use SDR50 tuning", val);
127         msk = FIELD_DP64(msk, SDHC_CAPAB, SDR50_TUNING, 0);
128 
129         val = FIELD_EX64(s->capareg, SDHC_CAPAB, RETUNING_MODE);
130         trace_sdhci_capareg("re-tuning mode", val);
131         msk = FIELD_DP64(msk, SDHC_CAPAB, RETUNING_MODE, 0);
132 
133         val = FIELD_EX64(s->capareg, SDHC_CAPAB, CLOCK_MULT);
134         trace_sdhci_capareg("clock multiplier", val);
135         msk = FIELD_DP64(msk, SDHC_CAPAB, CLOCK_MULT, 0);
136 
137     /* fallthrough */
138     case 2: /* default version */
139         val = FIELD_EX64(s->capareg, SDHC_CAPAB, ADMA2);
140         trace_sdhci_capareg("ADMA2", val);
141         msk = FIELD_DP64(msk, SDHC_CAPAB, ADMA2, 0);
142 
143         val = FIELD_EX64(s->capareg, SDHC_CAPAB, ADMA1);
144         trace_sdhci_capareg("ADMA1", val);
145         msk = FIELD_DP64(msk, SDHC_CAPAB, ADMA1, 0);
146 
147         val = FIELD_EX64(s->capareg, SDHC_CAPAB, BUS64BIT);
148         trace_sdhci_capareg("64-bit system bus", val);
149         msk = FIELD_DP64(msk, SDHC_CAPAB, BUS64BIT, 0);
150 
151     /* fallthrough */
152     case 1:
153         y = FIELD_EX64(s->capareg, SDHC_CAPAB, TOUNIT);
154         msk = FIELD_DP64(msk, SDHC_CAPAB, TOUNIT, 0);
155 
156         val = FIELD_EX64(s->capareg, SDHC_CAPAB, TOCLKFREQ);
157         trace_sdhci_capareg(y ? "timeout (MHz)" : "Timeout (KHz)", val);
158         if (sdhci_check_capab_freq_range(s, "timeout", val, errp)) {
159             return;
160         }
161         msk = FIELD_DP64(msk, SDHC_CAPAB, TOCLKFREQ, 0);
162 
163         val = FIELD_EX64(s->capareg, SDHC_CAPAB, BASECLKFREQ);
164         trace_sdhci_capareg(y ? "base (MHz)" : "Base (KHz)", val);
165         if (sdhci_check_capab_freq_range(s, "base", val, errp)) {
166             return;
167         }
168         msk = FIELD_DP64(msk, SDHC_CAPAB, BASECLKFREQ, 0);
169 
170         val = FIELD_EX64(s->capareg, SDHC_CAPAB, MAXBLOCKLENGTH);
171         if (val >= 3) {
172             error_setg(errp, "block size can be 512, 1024 or 2048 only");
173             return;
174         }
175         trace_sdhci_capareg("max block length", sdhci_get_fifolen(s));
176         msk = FIELD_DP64(msk, SDHC_CAPAB, MAXBLOCKLENGTH, 0);
177 
178         val = FIELD_EX64(s->capareg, SDHC_CAPAB, HIGHSPEED);
179         trace_sdhci_capareg("high speed", val);
180         msk = FIELD_DP64(msk, SDHC_CAPAB, HIGHSPEED, 0);
181 
182         val = FIELD_EX64(s->capareg, SDHC_CAPAB, SDMA);
183         trace_sdhci_capareg("SDMA", val);
184         msk = FIELD_DP64(msk, SDHC_CAPAB, SDMA, 0);
185 
186         val = FIELD_EX64(s->capareg, SDHC_CAPAB, SUSPRESUME);
187         trace_sdhci_capareg("suspend/resume", val);
188         msk = FIELD_DP64(msk, SDHC_CAPAB, SUSPRESUME, 0);
189 
190         val = FIELD_EX64(s->capareg, SDHC_CAPAB, V33);
191         trace_sdhci_capareg("3.3v", val);
192         msk = FIELD_DP64(msk, SDHC_CAPAB, V33, 0);
193 
194         val = FIELD_EX64(s->capareg, SDHC_CAPAB, V30);
195         trace_sdhci_capareg("3.0v", val);
196         msk = FIELD_DP64(msk, SDHC_CAPAB, V30, 0);
197 
198         val = FIELD_EX64(s->capareg, SDHC_CAPAB, V18);
199         trace_sdhci_capareg("1.8v", val);
200         msk = FIELD_DP64(msk, SDHC_CAPAB, V18, 0);
201         break;
202 
203     default:
204         error_setg(errp, "Unsupported spec version: %u", s->sd_spec_version);
205     }
206     if (msk) {
207         qemu_log_mask(LOG_UNIMP,
208                       "SDHCI: unknown CAPAB mask: 0x%016" PRIx64 "\n", msk);
209     }
210 }
211 
212 static uint8_t sdhci_slotint(SDHCIState *s)
213 {
214     return (s->norintsts & s->norintsigen) || (s->errintsts & s->errintsigen) ||
215          ((s->norintsts & SDHC_NIS_INSERT) && (s->wakcon & SDHC_WKUP_ON_INS)) ||
216          ((s->norintsts & SDHC_NIS_REMOVE) && (s->wakcon & SDHC_WKUP_ON_RMV));
217 }
218 
219 static inline void sdhci_update_irq(SDHCIState *s)
220 {
221     qemu_set_irq(s->irq, sdhci_slotint(s));
222 }
223 
224 static void sdhci_raise_insertion_irq(void *opaque)
225 {
226     SDHCIState *s = (SDHCIState *)opaque;
227 
228     if (s->norintsts & SDHC_NIS_REMOVE) {
229         timer_mod(s->insert_timer,
230                        qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + SDHC_INSERTION_DELAY);
231     } else {
232         s->prnsts = 0x1ff0000;
233         if (s->norintstsen & SDHC_NISEN_INSERT) {
234             s->norintsts |= SDHC_NIS_INSERT;
235         }
236         sdhci_update_irq(s);
237     }
238 }
239 
240 static void sdhci_set_inserted(DeviceState *dev, bool level)
241 {
242     SDHCIState *s = (SDHCIState *)dev;
243 
244     trace_sdhci_set_inserted(level ? "insert" : "eject");
245     if ((s->norintsts & SDHC_NIS_REMOVE) && level) {
246         /* Give target some time to notice card ejection */
247         timer_mod(s->insert_timer,
248                        qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + SDHC_INSERTION_DELAY);
249     } else {
250         if (level) {
251             s->prnsts = 0x1ff0000;
252             if (s->norintstsen & SDHC_NISEN_INSERT) {
253                 s->norintsts |= SDHC_NIS_INSERT;
254             }
255         } else {
256             s->prnsts = 0x1fa0000;
257             s->pwrcon &= ~SDHC_POWER_ON;
258             s->clkcon &= ~SDHC_CLOCK_SDCLK_EN;
259             if (s->norintstsen & SDHC_NISEN_REMOVE) {
260                 s->norintsts |= SDHC_NIS_REMOVE;
261             }
262         }
263         sdhci_update_irq(s);
264     }
265 }
266 
267 static void sdhci_set_readonly(DeviceState *dev, bool level)
268 {
269     SDHCIState *s = (SDHCIState *)dev;
270 
271     if (level) {
272         s->prnsts &= ~SDHC_WRITE_PROTECT;
273     } else {
274         /* Write enabled */
275         s->prnsts |= SDHC_WRITE_PROTECT;
276     }
277 }
278 
279 static void sdhci_reset(SDHCIState *s)
280 {
281     DeviceState *dev = DEVICE(s);
282 
283     timer_del(s->insert_timer);
284     timer_del(s->transfer_timer);
285 
286     /* Set all registers to 0. Capabilities/Version registers are not cleared
287      * and assumed to always preserve their value, given to them during
288      * initialization */
289     memset(&s->sdmasysad, 0, (uintptr_t)&s->capareg - (uintptr_t)&s->sdmasysad);
290 
291     /* Reset other state based on current card insertion/readonly status */
292     sdhci_set_inserted(dev, sdbus_get_inserted(&s->sdbus));
293     sdhci_set_readonly(dev, sdbus_get_readonly(&s->sdbus));
294 
295     s->data_count = 0;
296     s->stopped_state = sdhc_not_stopped;
297     s->pending_insert_state = false;
298 }
299 
300 static void sdhci_poweron_reset(DeviceState *dev)
301 {
302     /* QOM (ie power-on) reset. This is identical to reset
303      * commanded via device register apart from handling of the
304      * 'pending insert on powerup' quirk.
305      */
306     SDHCIState *s = (SDHCIState *)dev;
307 
308     sdhci_reset(s);
309 
310     if (s->pending_insert_quirk) {
311         s->pending_insert_state = true;
312     }
313 }
314 
315 static void sdhci_data_transfer(void *opaque);
316 
317 static void sdhci_send_command(SDHCIState *s)
318 {
319     SDRequest request;
320     uint8_t response[16];
321     int rlen;
322 
323     s->errintsts = 0;
324     s->acmd12errsts = 0;
325     request.cmd = s->cmdreg >> 8;
326     request.arg = s->argument;
327 
328     trace_sdhci_send_command(request.cmd, request.arg);
329     rlen = sdbus_do_command(&s->sdbus, &request, response);
330 
331     if (s->cmdreg & SDHC_CMD_RESPONSE) {
332         if (rlen == 4) {
333             s->rspreg[0] = (response[0] << 24) | (response[1] << 16) |
334                            (response[2] << 8)  |  response[3];
335             s->rspreg[1] = s->rspreg[2] = s->rspreg[3] = 0;
336             trace_sdhci_response4(s->rspreg[0]);
337         } else if (rlen == 16) {
338             s->rspreg[0] = (response[11] << 24) | (response[12] << 16) |
339                            (response[13] << 8) |  response[14];
340             s->rspreg[1] = (response[7] << 24) | (response[8] << 16) |
341                            (response[9] << 8)  |  response[10];
342             s->rspreg[2] = (response[3] << 24) | (response[4] << 16) |
343                            (response[5] << 8)  |  response[6];
344             s->rspreg[3] = (response[0] << 16) | (response[1] << 8) |
345                             response[2];
346             trace_sdhci_response16(s->rspreg[3], s->rspreg[2],
347                                    s->rspreg[1], s->rspreg[0]);
348         } else {
349             trace_sdhci_error("timeout waiting for command response");
350             if (s->errintstsen & SDHC_EISEN_CMDTIMEOUT) {
351                 s->errintsts |= SDHC_EIS_CMDTIMEOUT;
352                 s->norintsts |= SDHC_NIS_ERR;
353             }
354         }
355 
356         if (!(s->quirks & SDHCI_QUIRK_NO_BUSY_IRQ) &&
357             (s->norintstsen & SDHC_NISEN_TRSCMP) &&
358             (s->cmdreg & SDHC_CMD_RESPONSE) == SDHC_CMD_RSP_WITH_BUSY) {
359             s->norintsts |= SDHC_NIS_TRSCMP;
360         }
361     }
362 
363     if (s->norintstsen & SDHC_NISEN_CMDCMP) {
364         s->norintsts |= SDHC_NIS_CMDCMP;
365     }
366 
367     sdhci_update_irq(s);
368 
369     if (s->blksize && (s->cmdreg & SDHC_CMD_DATA_PRESENT)) {
370         s->data_count = 0;
371         sdhci_data_transfer(s);
372     }
373 }
374 
375 static void sdhci_end_transfer(SDHCIState *s)
376 {
377     /* Automatically send CMD12 to stop transfer if AutoCMD12 enabled */
378     if ((s->trnmod & SDHC_TRNS_ACMD12) != 0) {
379         SDRequest request;
380         uint8_t response[16];
381 
382         request.cmd = 0x0C;
383         request.arg = 0;
384         trace_sdhci_end_transfer(request.cmd, request.arg);
385         sdbus_do_command(&s->sdbus, &request, response);
386         /* Auto CMD12 response goes to the upper Response register */
387         s->rspreg[3] = (response[0] << 24) | (response[1] << 16) |
388                 (response[2] << 8) | response[3];
389     }
390 
391     s->prnsts &= ~(SDHC_DOING_READ | SDHC_DOING_WRITE |
392             SDHC_DAT_LINE_ACTIVE | SDHC_DATA_INHIBIT |
393             SDHC_SPACE_AVAILABLE | SDHC_DATA_AVAILABLE);
394 
395     if (s->norintstsen & SDHC_NISEN_TRSCMP) {
396         s->norintsts |= SDHC_NIS_TRSCMP;
397     }
398 
399     sdhci_update_irq(s);
400 }
401 
402 /*
403  * Programmed i/o data transfer
404  */
405 #define BLOCK_SIZE_MASK (4 * K_BYTE - 1)
406 
407 /* Fill host controller's read buffer with BLKSIZE bytes of data from card */
408 static void sdhci_read_block_from_card(SDHCIState *s)
409 {
410     int index = 0;
411     uint8_t data;
412     const uint16_t blk_size = s->blksize & BLOCK_SIZE_MASK;
413 
414     if ((s->trnmod & SDHC_TRNS_MULTI) &&
415             (s->trnmod & SDHC_TRNS_BLK_CNT_EN) && (s->blkcnt == 0)) {
416         return;
417     }
418 
419     for (index = 0; index < blk_size; index++) {
420         data = sdbus_read_data(&s->sdbus);
421         if (!FIELD_EX32(s->hostctl2, SDHC_HOSTCTL2, EXECUTE_TUNING)) {
422             /* Device is not in tunning */
423             s->fifo_buffer[index] = data;
424         }
425     }
426 
427     if (FIELD_EX32(s->hostctl2, SDHC_HOSTCTL2, EXECUTE_TUNING)) {
428         /* Device is in tunning */
429         s->hostctl2 &= ~R_SDHC_HOSTCTL2_EXECUTE_TUNING_MASK;
430         s->hostctl2 |= R_SDHC_HOSTCTL2_SAMPLING_CLKSEL_MASK;
431         s->prnsts &= ~(SDHC_DAT_LINE_ACTIVE | SDHC_DOING_READ |
432                        SDHC_DATA_INHIBIT);
433         goto read_done;
434     }
435 
436     /* New data now available for READ through Buffer Port Register */
437     s->prnsts |= SDHC_DATA_AVAILABLE;
438     if (s->norintstsen & SDHC_NISEN_RBUFRDY) {
439         s->norintsts |= SDHC_NIS_RBUFRDY;
440     }
441 
442     /* Clear DAT line active status if that was the last block */
443     if ((s->trnmod & SDHC_TRNS_MULTI) == 0 ||
444             ((s->trnmod & SDHC_TRNS_MULTI) && s->blkcnt == 1)) {
445         s->prnsts &= ~SDHC_DAT_LINE_ACTIVE;
446     }
447 
448     /* If stop at block gap request was set and it's not the last block of
449      * data - generate Block Event interrupt */
450     if (s->stopped_state == sdhc_gap_read && (s->trnmod & SDHC_TRNS_MULTI) &&
451             s->blkcnt != 1)    {
452         s->prnsts &= ~SDHC_DAT_LINE_ACTIVE;
453         if (s->norintstsen & SDHC_EISEN_BLKGAP) {
454             s->norintsts |= SDHC_EIS_BLKGAP;
455         }
456     }
457 
458 read_done:
459     sdhci_update_irq(s);
460 }
461 
462 /* Read @size byte of data from host controller @s BUFFER DATA PORT register */
463 static uint32_t sdhci_read_dataport(SDHCIState *s, unsigned size)
464 {
465     uint32_t value = 0;
466     int i;
467 
468     /* first check that a valid data exists in host controller input buffer */
469     if ((s->prnsts & SDHC_DATA_AVAILABLE) == 0) {
470         trace_sdhci_error("read from empty buffer");
471         return 0;
472     }
473 
474     for (i = 0; i < size; i++) {
475         value |= s->fifo_buffer[s->data_count] << i * 8;
476         s->data_count++;
477         /* check if we've read all valid data (blksize bytes) from buffer */
478         if ((s->data_count) >= (s->blksize & BLOCK_SIZE_MASK)) {
479             trace_sdhci_read_dataport(s->data_count);
480             s->prnsts &= ~SDHC_DATA_AVAILABLE; /* no more data in a buffer */
481             s->data_count = 0;  /* next buff read must start at position [0] */
482 
483             if (s->trnmod & SDHC_TRNS_BLK_CNT_EN) {
484                 s->blkcnt--;
485             }
486 
487             /* if that was the last block of data */
488             if ((s->trnmod & SDHC_TRNS_MULTI) == 0 ||
489                 ((s->trnmod & SDHC_TRNS_BLK_CNT_EN) && (s->blkcnt == 0)) ||
490                  /* stop at gap request */
491                 (s->stopped_state == sdhc_gap_read &&
492                  !(s->prnsts & SDHC_DAT_LINE_ACTIVE))) {
493                 sdhci_end_transfer(s);
494             } else { /* if there are more data, read next block from card */
495                 sdhci_read_block_from_card(s);
496             }
497             break;
498         }
499     }
500 
501     return value;
502 }
503 
504 /* Write data from host controller FIFO to card */
505 static void sdhci_write_block_to_card(SDHCIState *s)
506 {
507     int index = 0;
508 
509     if (s->prnsts & SDHC_SPACE_AVAILABLE) {
510         if (s->norintstsen & SDHC_NISEN_WBUFRDY) {
511             s->norintsts |= SDHC_NIS_WBUFRDY;
512         }
513         sdhci_update_irq(s);
514         return;
515     }
516 
517     if (s->trnmod & SDHC_TRNS_BLK_CNT_EN) {
518         if (s->blkcnt == 0) {
519             return;
520         } else {
521             s->blkcnt--;
522         }
523     }
524 
525     for (index = 0; index < (s->blksize & BLOCK_SIZE_MASK); index++) {
526         sdbus_write_data(&s->sdbus, s->fifo_buffer[index]);
527     }
528 
529     /* Next data can be written through BUFFER DATORT register */
530     s->prnsts |= SDHC_SPACE_AVAILABLE;
531 
532     /* Finish transfer if that was the last block of data */
533     if ((s->trnmod & SDHC_TRNS_MULTI) == 0 ||
534             ((s->trnmod & SDHC_TRNS_MULTI) &&
535             (s->trnmod & SDHC_TRNS_BLK_CNT_EN) && (s->blkcnt == 0))) {
536         sdhci_end_transfer(s);
537     } else if (s->norintstsen & SDHC_NISEN_WBUFRDY) {
538         s->norintsts |= SDHC_NIS_WBUFRDY;
539     }
540 
541     /* Generate Block Gap Event if requested and if not the last block */
542     if (s->stopped_state == sdhc_gap_write && (s->trnmod & SDHC_TRNS_MULTI) &&
543             s->blkcnt > 0) {
544         s->prnsts &= ~SDHC_DOING_WRITE;
545         if (s->norintstsen & SDHC_EISEN_BLKGAP) {
546             s->norintsts |= SDHC_EIS_BLKGAP;
547         }
548         sdhci_end_transfer(s);
549     }
550 
551     sdhci_update_irq(s);
552 }
553 
554 /* Write @size bytes of @value data to host controller @s Buffer Data Port
555  * register */
556 static void sdhci_write_dataport(SDHCIState *s, uint32_t value, unsigned size)
557 {
558     unsigned i;
559 
560     /* Check that there is free space left in a buffer */
561     if (!(s->prnsts & SDHC_SPACE_AVAILABLE)) {
562         trace_sdhci_error("Can't write to data buffer: buffer full");
563         return;
564     }
565 
566     for (i = 0; i < size; i++) {
567         s->fifo_buffer[s->data_count] = value & 0xFF;
568         s->data_count++;
569         value >>= 8;
570         if (s->data_count >= (s->blksize & BLOCK_SIZE_MASK)) {
571             trace_sdhci_write_dataport(s->data_count);
572             s->data_count = 0;
573             s->prnsts &= ~SDHC_SPACE_AVAILABLE;
574             if (s->prnsts & SDHC_DOING_WRITE) {
575                 sdhci_write_block_to_card(s);
576             }
577         }
578     }
579 }
580 
581 /*
582  * Single DMA data transfer
583  */
584 
585 /* Multi block SDMA transfer */
586 static void sdhci_sdma_transfer_multi_blocks(SDHCIState *s)
587 {
588     bool page_aligned = false;
589     unsigned int n, begin;
590     const uint16_t block_size = s->blksize & BLOCK_SIZE_MASK;
591     uint32_t boundary_chk = 1 << (((s->blksize & ~BLOCK_SIZE_MASK) >> 12) + 12);
592     uint32_t boundary_count = boundary_chk - (s->sdmasysad % boundary_chk);
593 
594     if (!(s->trnmod & SDHC_TRNS_BLK_CNT_EN) || !s->blkcnt) {
595         qemu_log_mask(LOG_UNIMP, "infinite transfer is not supported\n");
596         return;
597     }
598 
599     /* XXX: Some sd/mmc drivers (for example, u-boot-slp) do not account for
600      * possible stop at page boundary if initial address is not page aligned,
601      * allow them to work properly */
602     if ((s->sdmasysad % boundary_chk) == 0) {
603         page_aligned = true;
604     }
605 
606     if (s->trnmod & SDHC_TRNS_READ) {
607         s->prnsts |= SDHC_DOING_READ | SDHC_DATA_INHIBIT |
608                 SDHC_DAT_LINE_ACTIVE;
609         while (s->blkcnt) {
610             if (s->data_count == 0) {
611                 for (n = 0; n < block_size; n++) {
612                     s->fifo_buffer[n] = sdbus_read_data(&s->sdbus);
613                 }
614             }
615             begin = s->data_count;
616             if (((boundary_count + begin) < block_size) && page_aligned) {
617                 s->data_count = boundary_count + begin;
618                 boundary_count = 0;
619              } else {
620                 s->data_count = block_size;
621                 boundary_count -= block_size - begin;
622                 if (s->trnmod & SDHC_TRNS_BLK_CNT_EN) {
623                     s->blkcnt--;
624                 }
625             }
626             dma_memory_write(s->dma_as, s->sdmasysad,
627                              &s->fifo_buffer[begin], s->data_count - begin);
628             s->sdmasysad += s->data_count - begin;
629             if (s->data_count == block_size) {
630                 s->data_count = 0;
631             }
632             if (page_aligned && boundary_count == 0) {
633                 break;
634             }
635         }
636     } else {
637         s->prnsts |= SDHC_DOING_WRITE | SDHC_DATA_INHIBIT |
638                 SDHC_DAT_LINE_ACTIVE;
639         while (s->blkcnt) {
640             begin = s->data_count;
641             if (((boundary_count + begin) < block_size) && page_aligned) {
642                 s->data_count = boundary_count + begin;
643                 boundary_count = 0;
644              } else {
645                 s->data_count = block_size;
646                 boundary_count -= block_size - begin;
647             }
648             dma_memory_read(s->dma_as, s->sdmasysad,
649                             &s->fifo_buffer[begin], s->data_count - begin);
650             s->sdmasysad += s->data_count - begin;
651             if (s->data_count == block_size) {
652                 for (n = 0; n < block_size; n++) {
653                     sdbus_write_data(&s->sdbus, s->fifo_buffer[n]);
654                 }
655                 s->data_count = 0;
656                 if (s->trnmod & SDHC_TRNS_BLK_CNT_EN) {
657                     s->blkcnt--;
658                 }
659             }
660             if (page_aligned && boundary_count == 0) {
661                 break;
662             }
663         }
664     }
665 
666     if (s->blkcnt == 0) {
667         sdhci_end_transfer(s);
668     } else {
669         if (s->norintstsen & SDHC_NISEN_DMA) {
670             s->norintsts |= SDHC_NIS_DMA;
671         }
672         sdhci_update_irq(s);
673     }
674 }
675 
676 /* single block SDMA transfer */
677 static void sdhci_sdma_transfer_single_block(SDHCIState *s)
678 {
679     int n;
680     uint32_t datacnt = s->blksize & BLOCK_SIZE_MASK;
681 
682     if (s->trnmod & SDHC_TRNS_READ) {
683         for (n = 0; n < datacnt; n++) {
684             s->fifo_buffer[n] = sdbus_read_data(&s->sdbus);
685         }
686         dma_memory_write(s->dma_as, s->sdmasysad, s->fifo_buffer, datacnt);
687     } else {
688         dma_memory_read(s->dma_as, s->sdmasysad, s->fifo_buffer, datacnt);
689         for (n = 0; n < datacnt; n++) {
690             sdbus_write_data(&s->sdbus, s->fifo_buffer[n]);
691         }
692     }
693     s->blkcnt--;
694 
695     sdhci_end_transfer(s);
696 }
697 
698 typedef struct ADMADescr {
699     hwaddr addr;
700     uint16_t length;
701     uint8_t attr;
702     uint8_t incr;
703 } ADMADescr;
704 
705 static void get_adma_description(SDHCIState *s, ADMADescr *dscr)
706 {
707     uint32_t adma1 = 0;
708     uint64_t adma2 = 0;
709     hwaddr entry_addr = (hwaddr)s->admasysaddr;
710     switch (SDHC_DMA_TYPE(s->hostctl1)) {
711     case SDHC_CTRL_ADMA2_32:
712         dma_memory_read(s->dma_as, entry_addr, (uint8_t *)&adma2,
713                         sizeof(adma2));
714         adma2 = le64_to_cpu(adma2);
715         /* The spec does not specify endianness of descriptor table.
716          * We currently assume that it is LE.
717          */
718         dscr->addr = (hwaddr)extract64(adma2, 32, 32) & ~0x3ull;
719         dscr->length = (uint16_t)extract64(adma2, 16, 16);
720         dscr->attr = (uint8_t)extract64(adma2, 0, 7);
721         dscr->incr = 8;
722         break;
723     case SDHC_CTRL_ADMA1_32:
724         dma_memory_read(s->dma_as, entry_addr, (uint8_t *)&adma1,
725                         sizeof(adma1));
726         adma1 = le32_to_cpu(adma1);
727         dscr->addr = (hwaddr)(adma1 & 0xFFFFF000);
728         dscr->attr = (uint8_t)extract32(adma1, 0, 7);
729         dscr->incr = 4;
730         if ((dscr->attr & SDHC_ADMA_ATTR_ACT_MASK) == SDHC_ADMA_ATTR_SET_LEN) {
731             dscr->length = (uint16_t)extract32(adma1, 12, 16);
732         } else {
733             dscr->length = 4096;
734         }
735         break;
736     case SDHC_CTRL_ADMA2_64:
737         dma_memory_read(s->dma_as, entry_addr,
738                         (uint8_t *)(&dscr->attr), 1);
739         dma_memory_read(s->dma_as, entry_addr + 2,
740                         (uint8_t *)(&dscr->length), 2);
741         dscr->length = le16_to_cpu(dscr->length);
742         dma_memory_read(s->dma_as, entry_addr + 4,
743                         (uint8_t *)(&dscr->addr), 8);
744         dscr->addr = le64_to_cpu(dscr->addr);
745         dscr->attr &= (uint8_t) ~0xC0;
746         dscr->incr = 12;
747         break;
748     }
749 }
750 
751 /* Advanced DMA data transfer */
752 
753 static void sdhci_do_adma(SDHCIState *s)
754 {
755     unsigned int n, begin, length;
756     const uint16_t block_size = s->blksize & BLOCK_SIZE_MASK;
757     ADMADescr dscr = {};
758     int i;
759 
760     for (i = 0; i < SDHC_ADMA_DESCS_PER_DELAY; ++i) {
761         s->admaerr &= ~SDHC_ADMAERR_LENGTH_MISMATCH;
762 
763         get_adma_description(s, &dscr);
764         trace_sdhci_adma_loop(dscr.addr, dscr.length, dscr.attr);
765 
766         if ((dscr.attr & SDHC_ADMA_ATTR_VALID) == 0) {
767             /* Indicate that error occurred in ST_FDS state */
768             s->admaerr &= ~SDHC_ADMAERR_STATE_MASK;
769             s->admaerr |= SDHC_ADMAERR_STATE_ST_FDS;
770 
771             /* Generate ADMA error interrupt */
772             if (s->errintstsen & SDHC_EISEN_ADMAERR) {
773                 s->errintsts |= SDHC_EIS_ADMAERR;
774                 s->norintsts |= SDHC_NIS_ERR;
775             }
776 
777             sdhci_update_irq(s);
778             return;
779         }
780 
781         length = dscr.length ? dscr.length : 65536;
782 
783         switch (dscr.attr & SDHC_ADMA_ATTR_ACT_MASK) {
784         case SDHC_ADMA_ATTR_ACT_TRAN:  /* data transfer */
785 
786             if (s->trnmod & SDHC_TRNS_READ) {
787                 while (length) {
788                     if (s->data_count == 0) {
789                         for (n = 0; n < block_size; n++) {
790                             s->fifo_buffer[n] = sdbus_read_data(&s->sdbus);
791                         }
792                     }
793                     begin = s->data_count;
794                     if ((length + begin) < block_size) {
795                         s->data_count = length + begin;
796                         length = 0;
797                      } else {
798                         s->data_count = block_size;
799                         length -= block_size - begin;
800                     }
801                     dma_memory_write(s->dma_as, dscr.addr,
802                                      &s->fifo_buffer[begin],
803                                      s->data_count - begin);
804                     dscr.addr += s->data_count - begin;
805                     if (s->data_count == block_size) {
806                         s->data_count = 0;
807                         if (s->trnmod & SDHC_TRNS_BLK_CNT_EN) {
808                             s->blkcnt--;
809                             if (s->blkcnt == 0) {
810                                 break;
811                             }
812                         }
813                     }
814                 }
815             } else {
816                 while (length) {
817                     begin = s->data_count;
818                     if ((length + begin) < block_size) {
819                         s->data_count = length + begin;
820                         length = 0;
821                      } else {
822                         s->data_count = block_size;
823                         length -= block_size - begin;
824                     }
825                     dma_memory_read(s->dma_as, dscr.addr,
826                                     &s->fifo_buffer[begin],
827                                     s->data_count - begin);
828                     dscr.addr += s->data_count - begin;
829                     if (s->data_count == block_size) {
830                         for (n = 0; n < block_size; n++) {
831                             sdbus_write_data(&s->sdbus, s->fifo_buffer[n]);
832                         }
833                         s->data_count = 0;
834                         if (s->trnmod & SDHC_TRNS_BLK_CNT_EN) {
835                             s->blkcnt--;
836                             if (s->blkcnt == 0) {
837                                 break;
838                             }
839                         }
840                     }
841                 }
842             }
843             s->admasysaddr += dscr.incr;
844             break;
845         case SDHC_ADMA_ATTR_ACT_LINK:   /* link to next descriptor table */
846             s->admasysaddr = dscr.addr;
847             trace_sdhci_adma("link", s->admasysaddr);
848             break;
849         default:
850             s->admasysaddr += dscr.incr;
851             break;
852         }
853 
854         if (dscr.attr & SDHC_ADMA_ATTR_INT) {
855             trace_sdhci_adma("interrupt", s->admasysaddr);
856             if (s->norintstsen & SDHC_NISEN_DMA) {
857                 s->norintsts |= SDHC_NIS_DMA;
858             }
859 
860             sdhci_update_irq(s);
861         }
862 
863         /* ADMA transfer terminates if blkcnt == 0 or by END attribute */
864         if (((s->trnmod & SDHC_TRNS_BLK_CNT_EN) &&
865                     (s->blkcnt == 0)) || (dscr.attr & SDHC_ADMA_ATTR_END)) {
866             trace_sdhci_adma_transfer_completed();
867             if (length || ((dscr.attr & SDHC_ADMA_ATTR_END) &&
868                 (s->trnmod & SDHC_TRNS_BLK_CNT_EN) &&
869                 s->blkcnt != 0)) {
870                 trace_sdhci_error("SD/MMC host ADMA length mismatch");
871                 s->admaerr |= SDHC_ADMAERR_LENGTH_MISMATCH |
872                         SDHC_ADMAERR_STATE_ST_TFR;
873                 if (s->errintstsen & SDHC_EISEN_ADMAERR) {
874                     trace_sdhci_error("Set ADMA error flag");
875                     s->errintsts |= SDHC_EIS_ADMAERR;
876                     s->norintsts |= SDHC_NIS_ERR;
877                 }
878 
879                 sdhci_update_irq(s);
880             }
881             sdhci_end_transfer(s);
882             return;
883         }
884 
885     }
886 
887     /* we have unfinished business - reschedule to continue ADMA */
888     timer_mod(s->transfer_timer,
889                    qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + SDHC_TRANSFER_DELAY);
890 }
891 
892 /* Perform data transfer according to controller configuration */
893 
894 static void sdhci_data_transfer(void *opaque)
895 {
896     SDHCIState *s = (SDHCIState *)opaque;
897 
898     if (s->trnmod & SDHC_TRNS_DMA) {
899         switch (SDHC_DMA_TYPE(s->hostctl1)) {
900         case SDHC_CTRL_SDMA:
901             if ((s->blkcnt == 1) || !(s->trnmod & SDHC_TRNS_MULTI)) {
902                 sdhci_sdma_transfer_single_block(s);
903             } else {
904                 sdhci_sdma_transfer_multi_blocks(s);
905             }
906 
907             break;
908         case SDHC_CTRL_ADMA1_32:
909             if (!(s->capareg & R_SDHC_CAPAB_ADMA1_MASK)) {
910                 trace_sdhci_error("ADMA1 not supported");
911                 break;
912             }
913 
914             sdhci_do_adma(s);
915             break;
916         case SDHC_CTRL_ADMA2_32:
917             if (!(s->capareg & R_SDHC_CAPAB_ADMA2_MASK)) {
918                 trace_sdhci_error("ADMA2 not supported");
919                 break;
920             }
921 
922             sdhci_do_adma(s);
923             break;
924         case SDHC_CTRL_ADMA2_64:
925             if (!(s->capareg & R_SDHC_CAPAB_ADMA2_MASK) ||
926                     !(s->capareg & R_SDHC_CAPAB_BUS64BIT_MASK)) {
927                 trace_sdhci_error("64 bit ADMA not supported");
928                 break;
929             }
930 
931             sdhci_do_adma(s);
932             break;
933         default:
934             trace_sdhci_error("Unsupported DMA type");
935             break;
936         }
937     } else {
938         if ((s->trnmod & SDHC_TRNS_READ) && sdbus_data_ready(&s->sdbus)) {
939             s->prnsts |= SDHC_DOING_READ | SDHC_DATA_INHIBIT |
940                     SDHC_DAT_LINE_ACTIVE;
941             sdhci_read_block_from_card(s);
942         } else {
943             s->prnsts |= SDHC_DOING_WRITE | SDHC_DAT_LINE_ACTIVE |
944                     SDHC_SPACE_AVAILABLE | SDHC_DATA_INHIBIT;
945             sdhci_write_block_to_card(s);
946         }
947     }
948 }
949 
950 static bool sdhci_can_issue_command(SDHCIState *s)
951 {
952     if (!SDHC_CLOCK_IS_ON(s->clkcon) ||
953         (((s->prnsts & SDHC_DATA_INHIBIT) || s->stopped_state) &&
954         ((s->cmdreg & SDHC_CMD_DATA_PRESENT) ||
955         ((s->cmdreg & SDHC_CMD_RESPONSE) == SDHC_CMD_RSP_WITH_BUSY &&
956         !(SDHC_COMMAND_TYPE(s->cmdreg) == SDHC_CMD_ABORT))))) {
957         return false;
958     }
959 
960     return true;
961 }
962 
963 /* The Buffer Data Port register must be accessed in sequential and
964  * continuous manner */
965 static inline bool
966 sdhci_buff_access_is_sequential(SDHCIState *s, unsigned byte_num)
967 {
968     if ((s->data_count & 0x3) != byte_num) {
969         trace_sdhci_error("Non-sequential access to Buffer Data Port register"
970                           "is prohibited\n");
971         return false;
972     }
973     return true;
974 }
975 
976 static uint64_t sdhci_read(void *opaque, hwaddr offset, unsigned size)
977 {
978     SDHCIState *s = (SDHCIState *)opaque;
979     uint32_t ret = 0;
980 
981     switch (offset & ~0x3) {
982     case SDHC_SYSAD:
983         ret = s->sdmasysad;
984         break;
985     case SDHC_BLKSIZE:
986         ret = s->blksize | (s->blkcnt << 16);
987         break;
988     case SDHC_ARGUMENT:
989         ret = s->argument;
990         break;
991     case SDHC_TRNMOD:
992         ret = s->trnmod | (s->cmdreg << 16);
993         break;
994     case SDHC_RSPREG0 ... SDHC_RSPREG3:
995         ret = s->rspreg[((offset & ~0x3) - SDHC_RSPREG0) >> 2];
996         break;
997     case  SDHC_BDATA:
998         if (sdhci_buff_access_is_sequential(s, offset - SDHC_BDATA)) {
999             ret = sdhci_read_dataport(s, size);
1000             trace_sdhci_access("rd", size << 3, offset, "->", ret, ret);
1001             return ret;
1002         }
1003         break;
1004     case SDHC_PRNSTS:
1005         ret = s->prnsts;
1006         ret = FIELD_DP32(ret, SDHC_PRNSTS, DAT_LVL,
1007                          sdbus_get_dat_lines(&s->sdbus));
1008         ret = FIELD_DP32(ret, SDHC_PRNSTS, CMD_LVL,
1009                          sdbus_get_cmd_line(&s->sdbus));
1010         break;
1011     case SDHC_HOSTCTL:
1012         ret = s->hostctl1 | (s->pwrcon << 8) | (s->blkgap << 16) |
1013               (s->wakcon << 24);
1014         break;
1015     case SDHC_CLKCON:
1016         ret = s->clkcon | (s->timeoutcon << 16);
1017         break;
1018     case SDHC_NORINTSTS:
1019         ret = s->norintsts | (s->errintsts << 16);
1020         break;
1021     case SDHC_NORINTSTSEN:
1022         ret = s->norintstsen | (s->errintstsen << 16);
1023         break;
1024     case SDHC_NORINTSIGEN:
1025         ret = s->norintsigen | (s->errintsigen << 16);
1026         break;
1027     case SDHC_ACMD12ERRSTS:
1028         ret = s->acmd12errsts | (s->hostctl2 << 16);
1029         break;
1030     case SDHC_CAPAB:
1031         ret = (uint32_t)s->capareg;
1032         break;
1033     case SDHC_CAPAB + 4:
1034         ret = (uint32_t)(s->capareg >> 32);
1035         break;
1036     case SDHC_MAXCURR:
1037         ret = (uint32_t)s->maxcurr;
1038         break;
1039     case SDHC_MAXCURR + 4:
1040         ret = (uint32_t)(s->maxcurr >> 32);
1041         break;
1042     case SDHC_ADMAERR:
1043         ret =  s->admaerr;
1044         break;
1045     case SDHC_ADMASYSADDR:
1046         ret = (uint32_t)s->admasysaddr;
1047         break;
1048     case SDHC_ADMASYSADDR + 4:
1049         ret = (uint32_t)(s->admasysaddr >> 32);
1050         break;
1051     case SDHC_SLOT_INT_STATUS:
1052         ret = (s->version << 16) | sdhci_slotint(s);
1053         break;
1054     default:
1055         qemu_log_mask(LOG_UNIMP, "SDHC rd_%ub @0x%02" HWADDR_PRIx " "
1056                       "not implemented\n", size, offset);
1057         break;
1058     }
1059 
1060     ret >>= (offset & 0x3) * 8;
1061     ret &= (1ULL << (size * 8)) - 1;
1062     trace_sdhci_access("rd", size << 3, offset, "->", ret, ret);
1063     return ret;
1064 }
1065 
1066 static inline void sdhci_blkgap_write(SDHCIState *s, uint8_t value)
1067 {
1068     if ((value & SDHC_STOP_AT_GAP_REQ) && (s->blkgap & SDHC_STOP_AT_GAP_REQ)) {
1069         return;
1070     }
1071     s->blkgap = value & SDHC_STOP_AT_GAP_REQ;
1072 
1073     if ((value & SDHC_CONTINUE_REQ) && s->stopped_state &&
1074             (s->blkgap & SDHC_STOP_AT_GAP_REQ) == 0) {
1075         if (s->stopped_state == sdhc_gap_read) {
1076             s->prnsts |= SDHC_DAT_LINE_ACTIVE | SDHC_DOING_READ;
1077             sdhci_read_block_from_card(s);
1078         } else {
1079             s->prnsts |= SDHC_DAT_LINE_ACTIVE | SDHC_DOING_WRITE;
1080             sdhci_write_block_to_card(s);
1081         }
1082         s->stopped_state = sdhc_not_stopped;
1083     } else if (!s->stopped_state && (value & SDHC_STOP_AT_GAP_REQ)) {
1084         if (s->prnsts & SDHC_DOING_READ) {
1085             s->stopped_state = sdhc_gap_read;
1086         } else if (s->prnsts & SDHC_DOING_WRITE) {
1087             s->stopped_state = sdhc_gap_write;
1088         }
1089     }
1090 }
1091 
1092 static inline void sdhci_reset_write(SDHCIState *s, uint8_t value)
1093 {
1094     switch (value) {
1095     case SDHC_RESET_ALL:
1096         sdhci_reset(s);
1097         break;
1098     case SDHC_RESET_CMD:
1099         s->prnsts &= ~SDHC_CMD_INHIBIT;
1100         s->norintsts &= ~SDHC_NIS_CMDCMP;
1101         break;
1102     case SDHC_RESET_DATA:
1103         s->data_count = 0;
1104         s->prnsts &= ~(SDHC_SPACE_AVAILABLE | SDHC_DATA_AVAILABLE |
1105                 SDHC_DOING_READ | SDHC_DOING_WRITE |
1106                 SDHC_DATA_INHIBIT | SDHC_DAT_LINE_ACTIVE);
1107         s->blkgap &= ~(SDHC_STOP_AT_GAP_REQ | SDHC_CONTINUE_REQ);
1108         s->stopped_state = sdhc_not_stopped;
1109         s->norintsts &= ~(SDHC_NIS_WBUFRDY | SDHC_NIS_RBUFRDY |
1110                 SDHC_NIS_DMA | SDHC_NIS_TRSCMP | SDHC_NIS_BLKGAP);
1111         break;
1112     }
1113 }
1114 
1115 static void
1116 sdhci_write(void *opaque, hwaddr offset, uint64_t val, unsigned size)
1117 {
1118     SDHCIState *s = (SDHCIState *)opaque;
1119     unsigned shift =  8 * (offset & 0x3);
1120     uint32_t mask = ~(((1ULL << (size * 8)) - 1) << shift);
1121     uint32_t value = val;
1122     value <<= shift;
1123 
1124     switch (offset & ~0x3) {
1125     case SDHC_SYSAD:
1126         s->sdmasysad = (s->sdmasysad & mask) | value;
1127         MASKED_WRITE(s->sdmasysad, mask, value);
1128         /* Writing to last byte of sdmasysad might trigger transfer */
1129         if (!(mask & 0xFF000000) && TRANSFERRING_DATA(s->prnsts) && s->blkcnt &&
1130                 s->blksize && SDHC_DMA_TYPE(s->hostctl1) == SDHC_CTRL_SDMA) {
1131             if (s->trnmod & SDHC_TRNS_MULTI) {
1132                 sdhci_sdma_transfer_multi_blocks(s);
1133             } else {
1134                 sdhci_sdma_transfer_single_block(s);
1135             }
1136         }
1137         break;
1138     case SDHC_BLKSIZE:
1139         if (!TRANSFERRING_DATA(s->prnsts)) {
1140             MASKED_WRITE(s->blksize, mask, value);
1141             MASKED_WRITE(s->blkcnt, mask >> 16, value >> 16);
1142         }
1143 
1144         /* Limit block size to the maximum buffer size */
1145         if (extract32(s->blksize, 0, 12) > s->buf_maxsz) {
1146             qemu_log_mask(LOG_GUEST_ERROR, "%s: Size 0x%x is larger than " \
1147                           "the maximum buffer 0x%x", __func__, s->blksize,
1148                           s->buf_maxsz);
1149 
1150             s->blksize = deposit32(s->blksize, 0, 12, s->buf_maxsz);
1151         }
1152 
1153         break;
1154     case SDHC_ARGUMENT:
1155         MASKED_WRITE(s->argument, mask, value);
1156         break;
1157     case SDHC_TRNMOD:
1158         /* DMA can be enabled only if it is supported as indicated by
1159          * capabilities register */
1160         if (!(s->capareg & R_SDHC_CAPAB_SDMA_MASK)) {
1161             value &= ~SDHC_TRNS_DMA;
1162         }
1163         MASKED_WRITE(s->trnmod, mask, value & SDHC_TRNMOD_MASK);
1164         MASKED_WRITE(s->cmdreg, mask >> 16, value >> 16);
1165 
1166         /* Writing to the upper byte of CMDREG triggers SD command generation */
1167         if ((mask & 0xFF000000) || !sdhci_can_issue_command(s)) {
1168             break;
1169         }
1170 
1171         sdhci_send_command(s);
1172         break;
1173     case  SDHC_BDATA:
1174         if (sdhci_buff_access_is_sequential(s, offset - SDHC_BDATA)) {
1175             sdhci_write_dataport(s, value >> shift, size);
1176         }
1177         break;
1178     case SDHC_HOSTCTL:
1179         if (!(mask & 0xFF0000)) {
1180             sdhci_blkgap_write(s, value >> 16);
1181         }
1182         MASKED_WRITE(s->hostctl1, mask, value);
1183         MASKED_WRITE(s->pwrcon, mask >> 8, value >> 8);
1184         MASKED_WRITE(s->wakcon, mask >> 24, value >> 24);
1185         if (!(s->prnsts & SDHC_CARD_PRESENT) || ((s->pwrcon >> 1) & 0x7) < 5 ||
1186                 !(s->capareg & (1 << (31 - ((s->pwrcon >> 1) & 0x7))))) {
1187             s->pwrcon &= ~SDHC_POWER_ON;
1188         }
1189         break;
1190     case SDHC_CLKCON:
1191         if (!(mask & 0xFF000000)) {
1192             sdhci_reset_write(s, value >> 24);
1193         }
1194         MASKED_WRITE(s->clkcon, mask, value);
1195         MASKED_WRITE(s->timeoutcon, mask >> 16, value >> 16);
1196         if (s->clkcon & SDHC_CLOCK_INT_EN) {
1197             s->clkcon |= SDHC_CLOCK_INT_STABLE;
1198         } else {
1199             s->clkcon &= ~SDHC_CLOCK_INT_STABLE;
1200         }
1201         break;
1202     case SDHC_NORINTSTS:
1203         if (s->norintstsen & SDHC_NISEN_CARDINT) {
1204             value &= ~SDHC_NIS_CARDINT;
1205         }
1206         s->norintsts &= mask | ~value;
1207         s->errintsts &= (mask >> 16) | ~(value >> 16);
1208         if (s->errintsts) {
1209             s->norintsts |= SDHC_NIS_ERR;
1210         } else {
1211             s->norintsts &= ~SDHC_NIS_ERR;
1212         }
1213         sdhci_update_irq(s);
1214         break;
1215     case SDHC_NORINTSTSEN:
1216         MASKED_WRITE(s->norintstsen, mask, value);
1217         MASKED_WRITE(s->errintstsen, mask >> 16, value >> 16);
1218         s->norintsts &= s->norintstsen;
1219         s->errintsts &= s->errintstsen;
1220         if (s->errintsts) {
1221             s->norintsts |= SDHC_NIS_ERR;
1222         } else {
1223             s->norintsts &= ~SDHC_NIS_ERR;
1224         }
1225         /* Quirk for Raspberry Pi: pending card insert interrupt
1226          * appears when first enabled after power on */
1227         if ((s->norintstsen & SDHC_NISEN_INSERT) && s->pending_insert_state) {
1228             assert(s->pending_insert_quirk);
1229             s->norintsts |= SDHC_NIS_INSERT;
1230             s->pending_insert_state = false;
1231         }
1232         sdhci_update_irq(s);
1233         break;
1234     case SDHC_NORINTSIGEN:
1235         MASKED_WRITE(s->norintsigen, mask, value);
1236         MASKED_WRITE(s->errintsigen, mask >> 16, value >> 16);
1237         sdhci_update_irq(s);
1238         break;
1239     case SDHC_ADMAERR:
1240         MASKED_WRITE(s->admaerr, mask, value);
1241         break;
1242     case SDHC_ADMASYSADDR:
1243         s->admasysaddr = (s->admasysaddr & (0xFFFFFFFF00000000ULL |
1244                 (uint64_t)mask)) | (uint64_t)value;
1245         break;
1246     case SDHC_ADMASYSADDR + 4:
1247         s->admasysaddr = (s->admasysaddr & (0x00000000FFFFFFFFULL |
1248                 ((uint64_t)mask << 32))) | ((uint64_t)value << 32);
1249         break;
1250     case SDHC_FEAER:
1251         s->acmd12errsts |= value;
1252         s->errintsts |= (value >> 16) & s->errintstsen;
1253         if (s->acmd12errsts) {
1254             s->errintsts |= SDHC_EIS_CMD12ERR;
1255         }
1256         if (s->errintsts) {
1257             s->norintsts |= SDHC_NIS_ERR;
1258         }
1259         sdhci_update_irq(s);
1260         break;
1261     case SDHC_ACMD12ERRSTS:
1262         MASKED_WRITE(s->acmd12errsts, mask, value & UINT16_MAX);
1263         if (s->uhs_mode >= UHS_I) {
1264             MASKED_WRITE(s->hostctl2, mask >> 16, value >> 16);
1265 
1266             if (FIELD_EX32(s->hostctl2, SDHC_HOSTCTL2, V18_ENA)) {
1267                 sdbus_set_voltage(&s->sdbus, SD_VOLTAGE_1_8V);
1268             } else {
1269                 sdbus_set_voltage(&s->sdbus, SD_VOLTAGE_3_3V);
1270             }
1271         }
1272         break;
1273 
1274     case SDHC_CAPAB:
1275     case SDHC_CAPAB + 4:
1276     case SDHC_MAXCURR:
1277     case SDHC_MAXCURR + 4:
1278         qemu_log_mask(LOG_GUEST_ERROR, "SDHC wr_%ub @0x%02" HWADDR_PRIx
1279                       " <- 0x%08x read-only\n", size, offset, value >> shift);
1280         break;
1281 
1282     default:
1283         qemu_log_mask(LOG_UNIMP, "SDHC wr_%ub @0x%02" HWADDR_PRIx " <- 0x%08x "
1284                       "not implemented\n", size, offset, value >> shift);
1285         break;
1286     }
1287     trace_sdhci_access("wr", size << 3, offset, "<-",
1288                        value >> shift, value >> shift);
1289 }
1290 
1291 static const MemoryRegionOps sdhci_mmio_ops = {
1292     .read = sdhci_read,
1293     .write = sdhci_write,
1294     .valid = {
1295         .min_access_size = 1,
1296         .max_access_size = 4,
1297         .unaligned = false
1298     },
1299     .endianness = DEVICE_LITTLE_ENDIAN,
1300 };
1301 
1302 static void sdhci_init_readonly_registers(SDHCIState *s, Error **errp)
1303 {
1304     Error *local_err = NULL;
1305 
1306     switch (s->sd_spec_version) {
1307     case 2 ... 3:
1308         break;
1309     default:
1310         error_setg(errp, "Only Spec v2/v3 are supported");
1311         return;
1312     }
1313     s->version = (SDHC_HCVER_VENDOR << 8) | (s->sd_spec_version - 1);
1314 
1315     sdhci_check_capareg(s, &local_err);
1316     if (local_err) {
1317         error_propagate(errp, local_err);
1318         return;
1319     }
1320 }
1321 
1322 /* --- qdev common --- */
1323 
1324 #define DEFINE_SDHCI_COMMON_PROPERTIES(_state) \
1325     DEFINE_PROP_UINT8("sd-spec-version", _state, sd_spec_version, 2), \
1326     DEFINE_PROP_UINT8("uhs", _state, uhs_mode, UHS_NOT_SUPPORTED), \
1327     \
1328     /* Capabilities registers provide information on supported
1329      * features of this specific host controller implementation */ \
1330     DEFINE_PROP_UINT64("capareg", _state, capareg, SDHC_CAPAB_REG_DEFAULT), \
1331     DEFINE_PROP_UINT64("maxcurr", _state, maxcurr, 0)
1332 
1333 static void sdhci_initfn(SDHCIState *s)
1334 {
1335     qbus_create_inplace(&s->sdbus, sizeof(s->sdbus),
1336                         TYPE_SDHCI_BUS, DEVICE(s), "sd-bus");
1337 
1338     s->insert_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, sdhci_raise_insertion_irq, s);
1339     s->transfer_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, sdhci_data_transfer, s);
1340 
1341     s->io_ops = &sdhci_mmio_ops;
1342 }
1343 
1344 static void sdhci_uninitfn(SDHCIState *s)
1345 {
1346     timer_del(s->insert_timer);
1347     timer_free(s->insert_timer);
1348     timer_del(s->transfer_timer);
1349     timer_free(s->transfer_timer);
1350 
1351     g_free(s->fifo_buffer);
1352     s->fifo_buffer = NULL;
1353 }
1354 
1355 static void sdhci_common_realize(SDHCIState *s, Error **errp)
1356 {
1357     Error *local_err = NULL;
1358 
1359     sdhci_init_readonly_registers(s, &local_err);
1360     if (local_err) {
1361         error_propagate(errp, local_err);
1362         return;
1363     }
1364     s->buf_maxsz = sdhci_get_fifolen(s);
1365     s->fifo_buffer = g_malloc0(s->buf_maxsz);
1366 
1367     memory_region_init_io(&s->iomem, OBJECT(s), &sdhci_mmio_ops, s, "sdhci",
1368                           SDHC_REGISTERS_MAP_SIZE);
1369 }
1370 
1371 static void sdhci_common_unrealize(SDHCIState *s, Error **errp)
1372 {
1373     /* This function is expected to be called only once for each class:
1374      * - SysBus:    via DeviceClass->unrealize(),
1375      * - PCI:       via PCIDeviceClass->exit().
1376      * However to avoid double-free and/or use-after-free we still nullify
1377      * this variable (better safe than sorry!). */
1378     g_free(s->fifo_buffer);
1379     s->fifo_buffer = NULL;
1380 }
1381 
1382 static bool sdhci_pending_insert_vmstate_needed(void *opaque)
1383 {
1384     SDHCIState *s = opaque;
1385 
1386     return s->pending_insert_state;
1387 }
1388 
1389 static const VMStateDescription sdhci_pending_insert_vmstate = {
1390     .name = "sdhci/pending-insert",
1391     .version_id = 1,
1392     .minimum_version_id = 1,
1393     .needed = sdhci_pending_insert_vmstate_needed,
1394     .fields = (VMStateField[]) {
1395         VMSTATE_BOOL(pending_insert_state, SDHCIState),
1396         VMSTATE_END_OF_LIST()
1397     },
1398 };
1399 
1400 const VMStateDescription sdhci_vmstate = {
1401     .name = "sdhci",
1402     .version_id = 1,
1403     .minimum_version_id = 1,
1404     .fields = (VMStateField[]) {
1405         VMSTATE_UINT32(sdmasysad, SDHCIState),
1406         VMSTATE_UINT16(blksize, SDHCIState),
1407         VMSTATE_UINT16(blkcnt, SDHCIState),
1408         VMSTATE_UINT32(argument, SDHCIState),
1409         VMSTATE_UINT16(trnmod, SDHCIState),
1410         VMSTATE_UINT16(cmdreg, SDHCIState),
1411         VMSTATE_UINT32_ARRAY(rspreg, SDHCIState, 4),
1412         VMSTATE_UINT32(prnsts, SDHCIState),
1413         VMSTATE_UINT8(hostctl1, SDHCIState),
1414         VMSTATE_UINT8(pwrcon, SDHCIState),
1415         VMSTATE_UINT8(blkgap, SDHCIState),
1416         VMSTATE_UINT8(wakcon, SDHCIState),
1417         VMSTATE_UINT16(clkcon, SDHCIState),
1418         VMSTATE_UINT8(timeoutcon, SDHCIState),
1419         VMSTATE_UINT8(admaerr, SDHCIState),
1420         VMSTATE_UINT16(norintsts, SDHCIState),
1421         VMSTATE_UINT16(errintsts, SDHCIState),
1422         VMSTATE_UINT16(norintstsen, SDHCIState),
1423         VMSTATE_UINT16(errintstsen, SDHCIState),
1424         VMSTATE_UINT16(norintsigen, SDHCIState),
1425         VMSTATE_UINT16(errintsigen, SDHCIState),
1426         VMSTATE_UINT16(acmd12errsts, SDHCIState),
1427         VMSTATE_UINT16(data_count, SDHCIState),
1428         VMSTATE_UINT64(admasysaddr, SDHCIState),
1429         VMSTATE_UINT8(stopped_state, SDHCIState),
1430         VMSTATE_VBUFFER_UINT32(fifo_buffer, SDHCIState, 1, NULL, buf_maxsz),
1431         VMSTATE_TIMER_PTR(insert_timer, SDHCIState),
1432         VMSTATE_TIMER_PTR(transfer_timer, SDHCIState),
1433         VMSTATE_END_OF_LIST()
1434     },
1435     .subsections = (const VMStateDescription*[]) {
1436         &sdhci_pending_insert_vmstate,
1437         NULL
1438     },
1439 };
1440 
1441 static void sdhci_common_class_init(ObjectClass *klass, void *data)
1442 {
1443     DeviceClass *dc = DEVICE_CLASS(klass);
1444 
1445     set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
1446     dc->vmsd = &sdhci_vmstate;
1447     dc->reset = sdhci_poweron_reset;
1448 }
1449 
1450 /* --- qdev PCI --- */
1451 
1452 static Property sdhci_pci_properties[] = {
1453     DEFINE_SDHCI_COMMON_PROPERTIES(SDHCIState),
1454     DEFINE_PROP_END_OF_LIST(),
1455 };
1456 
1457 static void sdhci_pci_realize(PCIDevice *dev, Error **errp)
1458 {
1459     SDHCIState *s = PCI_SDHCI(dev);
1460     Error *local_err = NULL;
1461 
1462     sdhci_initfn(s);
1463     sdhci_common_realize(s, errp);
1464     if (local_err) {
1465         error_propagate(errp, local_err);
1466         return;
1467     }
1468 
1469     dev->config[PCI_CLASS_PROG] = 0x01; /* Standard Host supported DMA */
1470     dev->config[PCI_INTERRUPT_PIN] = 0x01; /* interrupt pin A */
1471     s->irq = pci_allocate_irq(dev);
1472     s->dma_as = pci_get_address_space(dev);
1473     pci_register_bar(dev, 0, PCI_BASE_ADDRESS_SPACE_MEMORY, &s->iomem);
1474 }
1475 
1476 static void sdhci_pci_exit(PCIDevice *dev)
1477 {
1478     SDHCIState *s = PCI_SDHCI(dev);
1479 
1480     sdhci_common_unrealize(s, &error_abort);
1481     sdhci_uninitfn(s);
1482 }
1483 
1484 static void sdhci_pci_class_init(ObjectClass *klass, void *data)
1485 {
1486     DeviceClass *dc = DEVICE_CLASS(klass);
1487     PCIDeviceClass *k = PCI_DEVICE_CLASS(klass);
1488 
1489     k->realize = sdhci_pci_realize;
1490     k->exit = sdhci_pci_exit;
1491     k->vendor_id = PCI_VENDOR_ID_REDHAT;
1492     k->device_id = PCI_DEVICE_ID_REDHAT_SDHCI;
1493     k->class_id = PCI_CLASS_SYSTEM_SDHCI;
1494     dc->props = sdhci_pci_properties;
1495 
1496     sdhci_common_class_init(klass, data);
1497 }
1498 
1499 static const TypeInfo sdhci_pci_info = {
1500     .name = TYPE_PCI_SDHCI,
1501     .parent = TYPE_PCI_DEVICE,
1502     .instance_size = sizeof(SDHCIState),
1503     .class_init = sdhci_pci_class_init,
1504     .interfaces = (InterfaceInfo[]) {
1505         { INTERFACE_CONVENTIONAL_PCI_DEVICE },
1506         { },
1507     },
1508 };
1509 
1510 /* --- qdev SysBus --- */
1511 
1512 static Property sdhci_sysbus_properties[] = {
1513     DEFINE_SDHCI_COMMON_PROPERTIES(SDHCIState),
1514     DEFINE_PROP_BOOL("pending-insert-quirk", SDHCIState, pending_insert_quirk,
1515                      false),
1516     DEFINE_PROP_LINK("dma", SDHCIState,
1517                      dma_mr, TYPE_MEMORY_REGION, MemoryRegion *),
1518     DEFINE_PROP_END_OF_LIST(),
1519 };
1520 
1521 static void sdhci_sysbus_init(Object *obj)
1522 {
1523     SDHCIState *s = SYSBUS_SDHCI(obj);
1524 
1525     sdhci_initfn(s);
1526 }
1527 
1528 static void sdhci_sysbus_finalize(Object *obj)
1529 {
1530     SDHCIState *s = SYSBUS_SDHCI(obj);
1531 
1532     if (s->dma_mr) {
1533         object_unparent(OBJECT(s->dma_mr));
1534     }
1535 
1536     sdhci_uninitfn(s);
1537 }
1538 
1539 static void sdhci_sysbus_realize(DeviceState *dev, Error ** errp)
1540 {
1541     SDHCIState *s = SYSBUS_SDHCI(dev);
1542     SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
1543     Error *local_err = NULL;
1544 
1545     sdhci_common_realize(s, errp);
1546     if (local_err) {
1547         error_propagate(errp, local_err);
1548         return;
1549     }
1550 
1551     if (s->dma_mr) {
1552         s->dma_as = &s->sysbus_dma_as;
1553         address_space_init(s->dma_as, s->dma_mr, "sdhci-dma");
1554     } else {
1555         /* use system_memory() if property "dma" not set */
1556         s->dma_as = &address_space_memory;
1557     }
1558 
1559     sysbus_init_irq(sbd, &s->irq);
1560 
1561     memory_region_init_io(&s->iomem, OBJECT(s), s->io_ops, s, "sdhci",
1562             SDHC_REGISTERS_MAP_SIZE);
1563 
1564     sysbus_init_mmio(sbd, &s->iomem);
1565 }
1566 
1567 static void sdhci_sysbus_unrealize(DeviceState *dev, Error **errp)
1568 {
1569     SDHCIState *s = SYSBUS_SDHCI(dev);
1570 
1571     sdhci_common_unrealize(s, &error_abort);
1572 
1573      if (s->dma_mr) {
1574         address_space_destroy(s->dma_as);
1575     }
1576 }
1577 
1578 static void sdhci_sysbus_class_init(ObjectClass *klass, void *data)
1579 {
1580     DeviceClass *dc = DEVICE_CLASS(klass);
1581 
1582     dc->props = sdhci_sysbus_properties;
1583     dc->realize = sdhci_sysbus_realize;
1584     dc->unrealize = sdhci_sysbus_unrealize;
1585 
1586     sdhci_common_class_init(klass, data);
1587 }
1588 
1589 static const TypeInfo sdhci_sysbus_info = {
1590     .name = TYPE_SYSBUS_SDHCI,
1591     .parent = TYPE_SYS_BUS_DEVICE,
1592     .instance_size = sizeof(SDHCIState),
1593     .instance_init = sdhci_sysbus_init,
1594     .instance_finalize = sdhci_sysbus_finalize,
1595     .class_init = sdhci_sysbus_class_init,
1596 };
1597 
1598 /* --- qdev bus master --- */
1599 
1600 static void sdhci_bus_class_init(ObjectClass *klass, void *data)
1601 {
1602     SDBusClass *sbc = SD_BUS_CLASS(klass);
1603 
1604     sbc->set_inserted = sdhci_set_inserted;
1605     sbc->set_readonly = sdhci_set_readonly;
1606 }
1607 
1608 static const TypeInfo sdhci_bus_info = {
1609     .name = TYPE_SDHCI_BUS,
1610     .parent = TYPE_SD_BUS,
1611     .instance_size = sizeof(SDBus),
1612     .class_init = sdhci_bus_class_init,
1613 };
1614 
1615 static uint64_t usdhc_read(void *opaque, hwaddr offset, unsigned size)
1616 {
1617     SDHCIState *s = SYSBUS_SDHCI(opaque);
1618     uint32_t ret;
1619     uint16_t hostctl1;
1620 
1621     switch (offset) {
1622     default:
1623         return sdhci_read(opaque, offset, size);
1624 
1625     case SDHC_HOSTCTL:
1626         /*
1627          * For a detailed explanation on the following bit
1628          * manipulation code see comments in a similar part of
1629          * usdhc_write()
1630          */
1631         hostctl1 = SDHC_DMA_TYPE(s->hostctl1) << (8 - 3);
1632 
1633         if (s->hostctl1 & SDHC_CTRL_8BITBUS) {
1634             hostctl1 |= ESDHC_CTRL_8BITBUS;
1635         }
1636 
1637         if (s->hostctl1 & SDHC_CTRL_4BITBUS) {
1638             hostctl1 |= ESDHC_CTRL_4BITBUS;
1639         }
1640 
1641         ret  = hostctl1;
1642         ret |= (uint32_t)s->blkgap << 16;
1643         ret |= (uint32_t)s->wakcon << 24;
1644 
1645         break;
1646 
1647     case ESDHC_DLL_CTRL:
1648     case ESDHC_TUNE_CTRL_STATUS:
1649     case ESDHC_UNDOCUMENTED_REG27:
1650     case ESDHC_TUNING_CTRL:
1651     case ESDHC_VENDOR_SPEC:
1652     case ESDHC_MIX_CTRL:
1653     case ESDHC_WTMK_LVL:
1654         ret = 0;
1655         break;
1656     }
1657 
1658     return ret;
1659 }
1660 
1661 static void
1662 usdhc_write(void *opaque, hwaddr offset, uint64_t val, unsigned size)
1663 {
1664     SDHCIState *s = SYSBUS_SDHCI(opaque);
1665     uint8_t hostctl1;
1666     uint32_t value = (uint32_t)val;
1667 
1668     switch (offset) {
1669     case ESDHC_DLL_CTRL:
1670     case ESDHC_TUNE_CTRL_STATUS:
1671     case ESDHC_UNDOCUMENTED_REG27:
1672     case ESDHC_TUNING_CTRL:
1673     case ESDHC_WTMK_LVL:
1674     case ESDHC_VENDOR_SPEC:
1675         break;
1676 
1677     case SDHC_HOSTCTL:
1678         /*
1679          * Here's What ESDHCI has at offset 0x28 (SDHC_HOSTCTL)
1680          *
1681          *       7         6     5      4      3      2        1      0
1682          * |-----------+--------+--------+-----------+----------+---------|
1683          * | Card      | Card   | Endian | DATA3     | Data     | Led     |
1684          * | Detect    | Detect | Mode   | as Card   | Transfer | Control |
1685          * | Signal    | Test   |        | Detection | Width    |         |
1686          * | Selection | Level  |        | Pin       |          |         |
1687          * |-----------+--------+--------+-----------+----------+---------|
1688          *
1689          * and 0x29
1690          *
1691          *  15      10 9    8
1692          * |----------+------|
1693          * | Reserved | DMA  |
1694          * |          | Sel. |
1695          * |          |      |
1696          * |----------+------|
1697          *
1698          * and here's what SDCHI spec expects those offsets to be:
1699          *
1700          * 0x28 (Host Control Register)
1701          *
1702          *     7        6         5       4  3      2         1        0
1703          * |--------+--------+----------+------+--------+----------+---------|
1704          * | Card   | Card   | Extended | DMA  | High   | Data     | LED     |
1705          * | Detect | Detect | Data     | Sel. | Speed  | Transfer | Control |
1706          * | Signal | Test   | Transfer |      | Enable | Width    |         |
1707          * | Sel.   | Level  | Width    |      |        |          |         |
1708          * |--------+--------+----------+------+--------+----------+---------|
1709          *
1710          * and 0x29 (Power Control Register)
1711          *
1712          * |----------------------------------|
1713          * | Power Control Register           |
1714          * |                                  |
1715          * | Description omitted,             |
1716          * | since it has no analog in ESDHCI |
1717          * |                                  |
1718          * |----------------------------------|
1719          *
1720          * Since offsets 0x2A and 0x2B should be compatible between
1721          * both IP specs we only need to reconcile least 16-bit of the
1722          * word we've been given.
1723          */
1724 
1725         /*
1726          * First, save bits 7 6 and 0 since they are identical
1727          */
1728         hostctl1 = value & (SDHC_CTRL_LED |
1729                             SDHC_CTRL_CDTEST_INS |
1730                             SDHC_CTRL_CDTEST_EN);
1731         /*
1732          * Second, split "Data Transfer Width" from bits 2 and 1 in to
1733          * bits 5 and 1
1734          */
1735         if (value & ESDHC_CTRL_8BITBUS) {
1736             hostctl1 |= SDHC_CTRL_8BITBUS;
1737         }
1738 
1739         if (value & ESDHC_CTRL_4BITBUS) {
1740             hostctl1 |= ESDHC_CTRL_4BITBUS;
1741         }
1742 
1743         /*
1744          * Third, move DMA select from bits 9 and 8 to bits 4 and 3
1745          */
1746         hostctl1 |= SDHC_DMA_TYPE(value >> (8 - 3));
1747 
1748         /*
1749          * Now place the corrected value into low 16-bit of the value
1750          * we are going to give standard SDHCI write function
1751          *
1752          * NOTE: This transformation should be the inverse of what can
1753          * be found in drivers/mmc/host/sdhci-esdhc-imx.c in Linux
1754          * kernel
1755          */
1756         value &= ~UINT16_MAX;
1757         value |= hostctl1;
1758         value |= (uint16_t)s->pwrcon << 8;
1759 
1760         sdhci_write(opaque, offset, value, size);
1761         break;
1762 
1763     case ESDHC_MIX_CTRL:
1764         /*
1765          * So, when SD/MMC stack in Linux tries to write to "Transfer
1766          * Mode Register", ESDHC i.MX quirk code will translate it
1767          * into a write to ESDHC_MIX_CTRL, so we do the opposite in
1768          * order to get where we started
1769          *
1770          * Note that Auto CMD23 Enable bit is located in a wrong place
1771          * on i.MX, but since it is not used by QEMU we do not care.
1772          *
1773          * We don't want to call sdhci_write(.., SDHC_TRNMOD, ...)
1774          * here becuase it will result in a call to
1775          * sdhci_send_command(s) which we don't want.
1776          *
1777          */
1778         s->trnmod = value & UINT16_MAX;
1779         break;
1780     case SDHC_TRNMOD:
1781         /*
1782          * Similar to above, but this time a write to "Command
1783          * Register" will be translated into a 4-byte write to
1784          * "Transfer Mode register" where lower 16-bit of value would
1785          * be set to zero. So what we do is fill those bits with
1786          * cached value from s->trnmod and let the SDHCI
1787          * infrastructure handle the rest
1788          */
1789         sdhci_write(opaque, offset, val | s->trnmod, size);
1790         break;
1791     case SDHC_BLKSIZE:
1792         /*
1793          * ESDHCI does not implement "Host SDMA Buffer Boundary", and
1794          * Linux driver will try to zero this field out which will
1795          * break the rest of SDHCI emulation.
1796          *
1797          * Linux defaults to maximum possible setting (512K boundary)
1798          * and it seems to be the only option that i.MX IP implements,
1799          * so we artificially set it to that value.
1800          */
1801         val |= 0x7 << 12;
1802         /* FALLTHROUGH */
1803     default:
1804         sdhci_write(opaque, offset, val, size);
1805         break;
1806     }
1807 }
1808 
1809 
1810 static const MemoryRegionOps usdhc_mmio_ops = {
1811     .read = usdhc_read,
1812     .write = usdhc_write,
1813     .valid = {
1814         .min_access_size = 1,
1815         .max_access_size = 4,
1816         .unaligned = false
1817     },
1818     .endianness = DEVICE_LITTLE_ENDIAN,
1819 };
1820 
1821 static void imx_usdhc_init(Object *obj)
1822 {
1823     SDHCIState *s = SYSBUS_SDHCI(obj);
1824 
1825     s->io_ops = &usdhc_mmio_ops;
1826     s->quirks = SDHCI_QUIRK_NO_BUSY_IRQ;
1827 }
1828 
1829 static const TypeInfo imx_usdhc_info = {
1830     .name = TYPE_IMX_USDHC,
1831     .parent = TYPE_SYSBUS_SDHCI,
1832     .instance_init = imx_usdhc_init,
1833 };
1834 
1835 static void sdhci_register_types(void)
1836 {
1837     type_register_static(&sdhci_pci_info);
1838     type_register_static(&sdhci_sysbus_info);
1839     type_register_static(&sdhci_bus_info);
1840     type_register_static(&imx_usdhc_info);
1841 }
1842 
1843 type_init(sdhci_register_types)
1844