xref: /openbmc/qemu/hw/sd/sdhci.c (revision 3539d84d)
1 /*
2  * SD Association Host Standard Specification v2.0 controller emulation
3  *
4  * Datasheet: PartA2_SD_Host_Controller_Simplified_Specification_Ver2.00.pdf
5  *
6  * Copyright (c) 2011 Samsung Electronics Co., Ltd.
7  * Mitsyanko Igor <i.mitsyanko@samsung.com>
8  * Peter A.G. Crosthwaite <peter.crosthwaite@petalogix.com>
9  *
10  * Based on MMC controller for Samsung S5PC1xx-based board emulation
11  * by Alexey Merkulov and Vladimir Monakhov.
12  *
13  * This program is free software; you can redistribute it and/or modify it
14  * under the terms of the GNU General Public License as published by the
15  * Free Software Foundation; either version 2 of the License, or (at your
16  * option) any later version.
17  *
18  * This program is distributed in the hope that it will be useful,
19  * but WITHOUT ANY WARRANTY; without even the implied warranty of
20  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
21  * See the GNU General Public License for more details.
22  *
23  * You should have received a copy of the GNU General Public License along
24  * with this program; if not, see <http://www.gnu.org/licenses/>.
25  */
26 
27 #include "qemu/osdep.h"
28 #include "qemu/units.h"
29 #include "qemu/error-report.h"
30 #include "qapi/error.h"
31 #include "hw/irq.h"
32 #include "hw/qdev-properties.h"
33 #include "sysemu/dma.h"
34 #include "qemu/timer.h"
35 #include "qemu/bitops.h"
36 #include "hw/sd/sdhci.h"
37 #include "migration/vmstate.h"
38 #include "sdhci-internal.h"
39 #include "qemu/log.h"
40 #include "qemu/module.h"
41 #include "trace.h"
42 #include "qom/object.h"
43 
44 #define TYPE_SDHCI_BUS "sdhci-bus"
45 /* This is reusing the SDBus typedef from SD_BUS */
46 DECLARE_INSTANCE_CHECKER(SDBus, SDHCI_BUS,
47                          TYPE_SDHCI_BUS)
48 
49 #define MASKED_WRITE(reg, mask, val)  (reg = (reg & (mask)) | (val))
50 
51 static inline unsigned int sdhci_get_fifolen(SDHCIState *s)
52 {
53     return 1 << (9 + FIELD_EX32(s->capareg, SDHC_CAPAB, MAXBLOCKLENGTH));
54 }
55 
56 /* return true on error */
57 static bool sdhci_check_capab_freq_range(SDHCIState *s, const char *desc,
58                                          uint8_t freq, Error **errp)
59 {
60     if (s->sd_spec_version >= 3) {
61         return false;
62     }
63     switch (freq) {
64     case 0:
65     case 10 ... 63:
66         break;
67     default:
68         error_setg(errp, "SD %s clock frequency can have value"
69                    "in range 0-63 only", desc);
70         return true;
71     }
72     return false;
73 }
74 
75 static void sdhci_check_capareg(SDHCIState *s, Error **errp)
76 {
77     uint64_t msk = s->capareg;
78     uint32_t val;
79     bool y;
80 
81     switch (s->sd_spec_version) {
82     case 4:
83         val = FIELD_EX64(s->capareg, SDHC_CAPAB, BUS64BIT_V4);
84         trace_sdhci_capareg("64-bit system bus (v4)", val);
85         msk = FIELD_DP64(msk, SDHC_CAPAB, BUS64BIT_V4, 0);
86 
87         val = FIELD_EX64(s->capareg, SDHC_CAPAB, UHS_II);
88         trace_sdhci_capareg("UHS-II", val);
89         msk = FIELD_DP64(msk, SDHC_CAPAB, UHS_II, 0);
90 
91         val = FIELD_EX64(s->capareg, SDHC_CAPAB, ADMA3);
92         trace_sdhci_capareg("ADMA3", val);
93         msk = FIELD_DP64(msk, SDHC_CAPAB, ADMA3, 0);
94 
95     /* fallthrough */
96     case 3:
97         val = FIELD_EX64(s->capareg, SDHC_CAPAB, ASYNC_INT);
98         trace_sdhci_capareg("async interrupt", val);
99         msk = FIELD_DP64(msk, SDHC_CAPAB, ASYNC_INT, 0);
100 
101         val = FIELD_EX64(s->capareg, SDHC_CAPAB, SLOT_TYPE);
102         if (val) {
103             error_setg(errp, "slot-type not supported");
104             return;
105         }
106         trace_sdhci_capareg("slot type", val);
107         msk = FIELD_DP64(msk, SDHC_CAPAB, SLOT_TYPE, 0);
108 
109         if (val != 2) {
110             val = FIELD_EX64(s->capareg, SDHC_CAPAB, EMBEDDED_8BIT);
111             trace_sdhci_capareg("8-bit bus", val);
112         }
113         msk = FIELD_DP64(msk, SDHC_CAPAB, EMBEDDED_8BIT, 0);
114 
115         val = FIELD_EX64(s->capareg, SDHC_CAPAB, BUS_SPEED);
116         trace_sdhci_capareg("bus speed mask", val);
117         msk = FIELD_DP64(msk, SDHC_CAPAB, BUS_SPEED, 0);
118 
119         val = FIELD_EX64(s->capareg, SDHC_CAPAB, DRIVER_STRENGTH);
120         trace_sdhci_capareg("driver strength mask", val);
121         msk = FIELD_DP64(msk, SDHC_CAPAB, DRIVER_STRENGTH, 0);
122 
123         val = FIELD_EX64(s->capareg, SDHC_CAPAB, TIMER_RETUNING);
124         trace_sdhci_capareg("timer re-tuning", val);
125         msk = FIELD_DP64(msk, SDHC_CAPAB, TIMER_RETUNING, 0);
126 
127         val = FIELD_EX64(s->capareg, SDHC_CAPAB, SDR50_TUNING);
128         trace_sdhci_capareg("use SDR50 tuning", val);
129         msk = FIELD_DP64(msk, SDHC_CAPAB, SDR50_TUNING, 0);
130 
131         val = FIELD_EX64(s->capareg, SDHC_CAPAB, RETUNING_MODE);
132         trace_sdhci_capareg("re-tuning mode", val);
133         msk = FIELD_DP64(msk, SDHC_CAPAB, RETUNING_MODE, 0);
134 
135         val = FIELD_EX64(s->capareg, SDHC_CAPAB, CLOCK_MULT);
136         trace_sdhci_capareg("clock multiplier", val);
137         msk = FIELD_DP64(msk, SDHC_CAPAB, CLOCK_MULT, 0);
138 
139     /* fallthrough */
140     case 2: /* default version */
141         val = FIELD_EX64(s->capareg, SDHC_CAPAB, ADMA2);
142         trace_sdhci_capareg("ADMA2", val);
143         msk = FIELD_DP64(msk, SDHC_CAPAB, ADMA2, 0);
144 
145         val = FIELD_EX64(s->capareg, SDHC_CAPAB, ADMA1);
146         trace_sdhci_capareg("ADMA1", val);
147         msk = FIELD_DP64(msk, SDHC_CAPAB, ADMA1, 0);
148 
149         val = FIELD_EX64(s->capareg, SDHC_CAPAB, BUS64BIT);
150         trace_sdhci_capareg("64-bit system bus (v3)", val);
151         msk = FIELD_DP64(msk, SDHC_CAPAB, BUS64BIT, 0);
152 
153     /* fallthrough */
154     case 1:
155         y = FIELD_EX64(s->capareg, SDHC_CAPAB, TOUNIT);
156         msk = FIELD_DP64(msk, SDHC_CAPAB, TOUNIT, 0);
157 
158         val = FIELD_EX64(s->capareg, SDHC_CAPAB, TOCLKFREQ);
159         trace_sdhci_capareg(y ? "timeout (MHz)" : "Timeout (KHz)", val);
160         if (sdhci_check_capab_freq_range(s, "timeout", val, errp)) {
161             return;
162         }
163         msk = FIELD_DP64(msk, SDHC_CAPAB, TOCLKFREQ, 0);
164 
165         val = FIELD_EX64(s->capareg, SDHC_CAPAB, BASECLKFREQ);
166         trace_sdhci_capareg(y ? "base (MHz)" : "Base (KHz)", val);
167         if (sdhci_check_capab_freq_range(s, "base", val, errp)) {
168             return;
169         }
170         msk = FIELD_DP64(msk, SDHC_CAPAB, BASECLKFREQ, 0);
171 
172         val = FIELD_EX64(s->capareg, SDHC_CAPAB, MAXBLOCKLENGTH);
173         if (val >= 3) {
174             error_setg(errp, "block size can be 512, 1024 or 2048 only");
175             return;
176         }
177         trace_sdhci_capareg("max block length", sdhci_get_fifolen(s));
178         msk = FIELD_DP64(msk, SDHC_CAPAB, MAXBLOCKLENGTH, 0);
179 
180         val = FIELD_EX64(s->capareg, SDHC_CAPAB, HIGHSPEED);
181         trace_sdhci_capareg("high speed", val);
182         msk = FIELD_DP64(msk, SDHC_CAPAB, HIGHSPEED, 0);
183 
184         val = FIELD_EX64(s->capareg, SDHC_CAPAB, SDMA);
185         trace_sdhci_capareg("SDMA", val);
186         msk = FIELD_DP64(msk, SDHC_CAPAB, SDMA, 0);
187 
188         val = FIELD_EX64(s->capareg, SDHC_CAPAB, SUSPRESUME);
189         trace_sdhci_capareg("suspend/resume", val);
190         msk = FIELD_DP64(msk, SDHC_CAPAB, SUSPRESUME, 0);
191 
192         val = FIELD_EX64(s->capareg, SDHC_CAPAB, V33);
193         trace_sdhci_capareg("3.3v", val);
194         msk = FIELD_DP64(msk, SDHC_CAPAB, V33, 0);
195 
196         val = FIELD_EX64(s->capareg, SDHC_CAPAB, V30);
197         trace_sdhci_capareg("3.0v", val);
198         msk = FIELD_DP64(msk, SDHC_CAPAB, V30, 0);
199 
200         val = FIELD_EX64(s->capareg, SDHC_CAPAB, V18);
201         trace_sdhci_capareg("1.8v", val);
202         msk = FIELD_DP64(msk, SDHC_CAPAB, V18, 0);
203         break;
204 
205     default:
206         error_setg(errp, "Unsupported spec version: %u", s->sd_spec_version);
207     }
208     if (msk) {
209         qemu_log_mask(LOG_UNIMP,
210                       "SDHCI: unknown CAPAB mask: 0x%016" PRIx64 "\n", msk);
211     }
212 }
213 
214 static uint8_t sdhci_slotint(SDHCIState *s)
215 {
216     return (s->norintsts & s->norintsigen) || (s->errintsts & s->errintsigen) ||
217          ((s->norintsts & SDHC_NIS_INSERT) && (s->wakcon & SDHC_WKUP_ON_INS)) ||
218          ((s->norintsts & SDHC_NIS_REMOVE) && (s->wakcon & SDHC_WKUP_ON_RMV));
219 }
220 
221 /* Return true if IRQ was pending and delivered */
222 static bool sdhci_update_irq(SDHCIState *s)
223 {
224     bool pending = sdhci_slotint(s);
225 
226     qemu_set_irq(s->irq, pending);
227 
228     return pending;
229 }
230 
231 static void sdhci_raise_insertion_irq(void *opaque)
232 {
233     SDHCIState *s = (SDHCIState *)opaque;
234 
235     if (s->norintsts & SDHC_NIS_REMOVE) {
236         timer_mod(s->insert_timer,
237                        qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + SDHC_INSERTION_DELAY);
238     } else {
239         s->prnsts = 0x1ff0000;
240         if (s->norintstsen & SDHC_NISEN_INSERT) {
241             s->norintsts |= SDHC_NIS_INSERT;
242         }
243         sdhci_update_irq(s);
244     }
245 }
246 
247 static void sdhci_set_inserted(DeviceState *dev, bool level)
248 {
249     SDHCIState *s = (SDHCIState *)dev;
250 
251     trace_sdhci_set_inserted(level ? "insert" : "eject");
252     if ((s->norintsts & SDHC_NIS_REMOVE) && level) {
253         /* Give target some time to notice card ejection */
254         timer_mod(s->insert_timer,
255                        qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + SDHC_INSERTION_DELAY);
256     } else {
257         if (level) {
258             s->prnsts = 0x1ff0000;
259             if (s->norintstsen & SDHC_NISEN_INSERT) {
260                 s->norintsts |= SDHC_NIS_INSERT;
261             }
262         } else {
263             s->prnsts = 0x1fa0000;
264             s->pwrcon &= ~SDHC_POWER_ON;
265             s->clkcon &= ~SDHC_CLOCK_SDCLK_EN;
266             if (s->norintstsen & SDHC_NISEN_REMOVE) {
267                 s->norintsts |= SDHC_NIS_REMOVE;
268             }
269         }
270         sdhci_update_irq(s);
271     }
272 }
273 
274 static void sdhci_set_readonly(DeviceState *dev, bool level)
275 {
276     SDHCIState *s = (SDHCIState *)dev;
277 
278     if (level) {
279         s->prnsts &= ~SDHC_WRITE_PROTECT;
280     } else {
281         /* Write enabled */
282         s->prnsts |= SDHC_WRITE_PROTECT;
283     }
284 }
285 
286 static void sdhci_reset(SDHCIState *s)
287 {
288     DeviceState *dev = DEVICE(s);
289 
290     timer_del(s->insert_timer);
291     timer_del(s->transfer_timer);
292 
293     /* Set all registers to 0. Capabilities/Version registers are not cleared
294      * and assumed to always preserve their value, given to them during
295      * initialization */
296     memset(&s->sdmasysad, 0, (uintptr_t)&s->capareg - (uintptr_t)&s->sdmasysad);
297 
298     /* Reset other state based on current card insertion/readonly status */
299     sdhci_set_inserted(dev, sdbus_get_inserted(&s->sdbus));
300     sdhci_set_readonly(dev, sdbus_get_readonly(&s->sdbus));
301 
302     s->data_count = 0;
303     s->stopped_state = sdhc_not_stopped;
304     s->pending_insert_state = false;
305 }
306 
307 static void sdhci_poweron_reset(DeviceState *dev)
308 {
309     /* QOM (ie power-on) reset. This is identical to reset
310      * commanded via device register apart from handling of the
311      * 'pending insert on powerup' quirk.
312      */
313     SDHCIState *s = (SDHCIState *)dev;
314 
315     sdhci_reset(s);
316 
317     if (s->pending_insert_quirk) {
318         s->pending_insert_state = true;
319     }
320 }
321 
322 static void sdhci_data_transfer(void *opaque);
323 
324 static void sdhci_send_command(SDHCIState *s)
325 {
326     SDRequest request;
327     uint8_t response[16];
328     int rlen;
329     bool timeout = false;
330 
331     s->errintsts = 0;
332     s->acmd12errsts = 0;
333     request.cmd = s->cmdreg >> 8;
334     request.arg = s->argument;
335 
336     trace_sdhci_send_command(request.cmd, request.arg);
337     rlen = sdbus_do_command(&s->sdbus, &request, response);
338 
339     if (s->cmdreg & SDHC_CMD_RESPONSE) {
340         if (rlen == 4) {
341             s->rspreg[0] = ldl_be_p(response);
342             s->rspreg[1] = s->rspreg[2] = s->rspreg[3] = 0;
343             trace_sdhci_response4(s->rspreg[0]);
344         } else if (rlen == 16) {
345             s->rspreg[0] = ldl_be_p(&response[11]);
346             s->rspreg[1] = ldl_be_p(&response[7]);
347             s->rspreg[2] = ldl_be_p(&response[3]);
348             s->rspreg[3] = (response[0] << 16) | (response[1] << 8) |
349                             response[2];
350             trace_sdhci_response16(s->rspreg[3], s->rspreg[2],
351                                    s->rspreg[1], s->rspreg[0]);
352         } else {
353             timeout = true;
354             trace_sdhci_error("timeout waiting for command response");
355             if (s->errintstsen & SDHC_EISEN_CMDTIMEOUT) {
356                 s->errintsts |= SDHC_EIS_CMDTIMEOUT;
357                 s->norintsts |= SDHC_NIS_ERR;
358             }
359         }
360 
361         if (!(s->quirks & SDHCI_QUIRK_NO_BUSY_IRQ) &&
362             (s->norintstsen & SDHC_NISEN_TRSCMP) &&
363             (s->cmdreg & SDHC_CMD_RESPONSE) == SDHC_CMD_RSP_WITH_BUSY) {
364             s->norintsts |= SDHC_NIS_TRSCMP;
365         }
366     }
367 
368     if (s->norintstsen & SDHC_NISEN_CMDCMP) {
369         s->norintsts |= SDHC_NIS_CMDCMP;
370     }
371 
372     sdhci_update_irq(s);
373 
374     if (!timeout && s->blksize && (s->cmdreg & SDHC_CMD_DATA_PRESENT)) {
375         s->data_count = 0;
376         sdhci_data_transfer(s);
377     }
378 }
379 
380 static void sdhci_end_transfer(SDHCIState *s)
381 {
382     /* Automatically send CMD12 to stop transfer if AutoCMD12 enabled */
383     if ((s->trnmod & SDHC_TRNS_ACMD12) != 0) {
384         SDRequest request;
385         uint8_t response[16];
386 
387         request.cmd = 0x0C;
388         request.arg = 0;
389         trace_sdhci_end_transfer(request.cmd, request.arg);
390         sdbus_do_command(&s->sdbus, &request, response);
391         /* Auto CMD12 response goes to the upper Response register */
392         s->rspreg[3] = ldl_be_p(response);
393     }
394 
395     s->prnsts &= ~(SDHC_DOING_READ | SDHC_DOING_WRITE |
396             SDHC_DAT_LINE_ACTIVE | SDHC_DATA_INHIBIT |
397             SDHC_SPACE_AVAILABLE | SDHC_DATA_AVAILABLE);
398 
399     if (s->norintstsen & SDHC_NISEN_TRSCMP) {
400         s->norintsts |= SDHC_NIS_TRSCMP;
401     }
402 
403     sdhci_update_irq(s);
404 }
405 
406 /*
407  * Programmed i/o data transfer
408  */
409 #define BLOCK_SIZE_MASK (4 * KiB - 1)
410 
411 /* Fill host controller's read buffer with BLKSIZE bytes of data from card */
412 static void sdhci_read_block_from_card(SDHCIState *s)
413 {
414     const uint16_t blk_size = s->blksize & BLOCK_SIZE_MASK;
415 
416     if ((s->trnmod & SDHC_TRNS_MULTI) &&
417             (s->trnmod & SDHC_TRNS_BLK_CNT_EN) && (s->blkcnt == 0)) {
418         return;
419     }
420 
421     if (!FIELD_EX32(s->hostctl2, SDHC_HOSTCTL2, EXECUTE_TUNING)) {
422         /* Device is not in tuning */
423         sdbus_read_data(&s->sdbus, s->fifo_buffer, blk_size);
424     }
425 
426     if (FIELD_EX32(s->hostctl2, SDHC_HOSTCTL2, EXECUTE_TUNING)) {
427         /* Device is in tuning */
428         s->hostctl2 &= ~R_SDHC_HOSTCTL2_EXECUTE_TUNING_MASK;
429         s->hostctl2 |= R_SDHC_HOSTCTL2_SAMPLING_CLKSEL_MASK;
430         s->prnsts &= ~(SDHC_DAT_LINE_ACTIVE | SDHC_DOING_READ |
431                        SDHC_DATA_INHIBIT);
432         goto read_done;
433     }
434 
435     /* New data now available for READ through Buffer Port Register */
436     s->prnsts |= SDHC_DATA_AVAILABLE;
437     if (s->norintstsen & SDHC_NISEN_RBUFRDY) {
438         s->norintsts |= SDHC_NIS_RBUFRDY;
439     }
440 
441     /* Clear DAT line active status if that was the last block */
442     if ((s->trnmod & SDHC_TRNS_MULTI) == 0 ||
443             ((s->trnmod & SDHC_TRNS_MULTI) && s->blkcnt == 1)) {
444         s->prnsts &= ~SDHC_DAT_LINE_ACTIVE;
445     }
446 
447     /* If stop at block gap request was set and it's not the last block of
448      * data - generate Block Event interrupt */
449     if (s->stopped_state == sdhc_gap_read && (s->trnmod & SDHC_TRNS_MULTI) &&
450             s->blkcnt != 1)    {
451         s->prnsts &= ~SDHC_DAT_LINE_ACTIVE;
452         if (s->norintstsen & SDHC_EISEN_BLKGAP) {
453             s->norintsts |= SDHC_EIS_BLKGAP;
454         }
455     }
456 
457 read_done:
458     sdhci_update_irq(s);
459 }
460 
461 /* Read @size byte of data from host controller @s BUFFER DATA PORT register */
462 static uint32_t sdhci_read_dataport(SDHCIState *s, unsigned size)
463 {
464     uint32_t value = 0;
465     int i;
466 
467     /* first check that a valid data exists in host controller input buffer */
468     if ((s->prnsts & SDHC_DATA_AVAILABLE) == 0) {
469         trace_sdhci_error("read from empty buffer");
470         return 0;
471     }
472 
473     for (i = 0; i < size; i++) {
474         value |= s->fifo_buffer[s->data_count] << i * 8;
475         s->data_count++;
476         /* check if we've read all valid data (blksize bytes) from buffer */
477         if ((s->data_count) >= (s->blksize & BLOCK_SIZE_MASK)) {
478             trace_sdhci_read_dataport(s->data_count);
479             s->prnsts &= ~SDHC_DATA_AVAILABLE; /* no more data in a buffer */
480             s->data_count = 0;  /* next buff read must start at position [0] */
481 
482             if (s->trnmod & SDHC_TRNS_BLK_CNT_EN) {
483                 s->blkcnt--;
484             }
485 
486             /* if that was the last block of data */
487             if ((s->trnmod & SDHC_TRNS_MULTI) == 0 ||
488                 ((s->trnmod & SDHC_TRNS_BLK_CNT_EN) && (s->blkcnt == 0)) ||
489                  /* stop at gap request */
490                 (s->stopped_state == sdhc_gap_read &&
491                  !(s->prnsts & SDHC_DAT_LINE_ACTIVE))) {
492                 sdhci_end_transfer(s);
493             } else { /* if there are more data, read next block from card */
494                 sdhci_read_block_from_card(s);
495             }
496             break;
497         }
498     }
499 
500     return value;
501 }
502 
503 /* Write data from host controller FIFO to card */
504 static void sdhci_write_block_to_card(SDHCIState *s)
505 {
506     if (s->prnsts & SDHC_SPACE_AVAILABLE) {
507         if (s->norintstsen & SDHC_NISEN_WBUFRDY) {
508             s->norintsts |= SDHC_NIS_WBUFRDY;
509         }
510         sdhci_update_irq(s);
511         return;
512     }
513 
514     if (s->trnmod & SDHC_TRNS_BLK_CNT_EN) {
515         if (s->blkcnt == 0) {
516             return;
517         } else {
518             s->blkcnt--;
519         }
520     }
521 
522     sdbus_write_data(&s->sdbus, s->fifo_buffer, s->blksize & BLOCK_SIZE_MASK);
523 
524     /* Next data can be written through BUFFER DATORT register */
525     s->prnsts |= SDHC_SPACE_AVAILABLE;
526 
527     /* Finish transfer if that was the last block of data */
528     if ((s->trnmod & SDHC_TRNS_MULTI) == 0 ||
529             ((s->trnmod & SDHC_TRNS_MULTI) &&
530             (s->trnmod & SDHC_TRNS_BLK_CNT_EN) && (s->blkcnt == 0))) {
531         sdhci_end_transfer(s);
532     } else if (s->norintstsen & SDHC_NISEN_WBUFRDY) {
533         s->norintsts |= SDHC_NIS_WBUFRDY;
534     }
535 
536     /* Generate Block Gap Event if requested and if not the last block */
537     if (s->stopped_state == sdhc_gap_write && (s->trnmod & SDHC_TRNS_MULTI) &&
538             s->blkcnt > 0) {
539         s->prnsts &= ~SDHC_DOING_WRITE;
540         if (s->norintstsen & SDHC_EISEN_BLKGAP) {
541             s->norintsts |= SDHC_EIS_BLKGAP;
542         }
543         sdhci_end_transfer(s);
544     }
545 
546     sdhci_update_irq(s);
547 }
548 
549 /* Write @size bytes of @value data to host controller @s Buffer Data Port
550  * register */
551 static void sdhci_write_dataport(SDHCIState *s, uint32_t value, unsigned size)
552 {
553     unsigned i;
554 
555     /* Check that there is free space left in a buffer */
556     if (!(s->prnsts & SDHC_SPACE_AVAILABLE)) {
557         trace_sdhci_error("Can't write to data buffer: buffer full");
558         return;
559     }
560 
561     for (i = 0; i < size; i++) {
562         s->fifo_buffer[s->data_count] = value & 0xFF;
563         s->data_count++;
564         value >>= 8;
565         if (s->data_count >= (s->blksize & BLOCK_SIZE_MASK)) {
566             trace_sdhci_write_dataport(s->data_count);
567             s->data_count = 0;
568             s->prnsts &= ~SDHC_SPACE_AVAILABLE;
569             if (s->prnsts & SDHC_DOING_WRITE) {
570                 sdhci_write_block_to_card(s);
571             }
572         }
573     }
574 }
575 
576 /*
577  * Single DMA data transfer
578  */
579 
580 /* Multi block SDMA transfer */
581 static void sdhci_sdma_transfer_multi_blocks(SDHCIState *s)
582 {
583     bool page_aligned = false;
584     unsigned int begin;
585     const uint16_t block_size = s->blksize & BLOCK_SIZE_MASK;
586     uint32_t boundary_chk = 1 << (((s->blksize & ~BLOCK_SIZE_MASK) >> 12) + 12);
587     uint32_t boundary_count = boundary_chk - (s->sdmasysad % boundary_chk);
588 
589     if (!(s->trnmod & SDHC_TRNS_BLK_CNT_EN) || !s->blkcnt) {
590         qemu_log_mask(LOG_UNIMP, "infinite transfer is not supported\n");
591         return;
592     }
593 
594     /* XXX: Some sd/mmc drivers (for example, u-boot-slp) do not account for
595      * possible stop at page boundary if initial address is not page aligned,
596      * allow them to work properly */
597     if ((s->sdmasysad % boundary_chk) == 0) {
598         page_aligned = true;
599     }
600 
601     s->prnsts |= SDHC_DATA_INHIBIT | SDHC_DAT_LINE_ACTIVE;
602     if (s->trnmod & SDHC_TRNS_READ) {
603         s->prnsts |= SDHC_DOING_READ;
604         while (s->blkcnt) {
605             if (s->data_count == 0) {
606                 sdbus_read_data(&s->sdbus, s->fifo_buffer, block_size);
607             }
608             begin = s->data_count;
609             if (((boundary_count + begin) < block_size) && page_aligned) {
610                 s->data_count = boundary_count + begin;
611                 boundary_count = 0;
612              } else {
613                 s->data_count = block_size;
614                 boundary_count -= block_size - begin;
615                 if (s->trnmod & SDHC_TRNS_BLK_CNT_EN) {
616                     s->blkcnt--;
617                 }
618             }
619             dma_memory_write(s->dma_as, s->sdmasysad,
620                              &s->fifo_buffer[begin], s->data_count - begin);
621             s->sdmasysad += s->data_count - begin;
622             if (s->data_count == block_size) {
623                 s->data_count = 0;
624             }
625             if (page_aligned && boundary_count == 0) {
626                 break;
627             }
628         }
629     } else {
630         s->prnsts |= SDHC_DOING_WRITE;
631         while (s->blkcnt) {
632             begin = s->data_count;
633             if (((boundary_count + begin) < block_size) && page_aligned) {
634                 s->data_count = boundary_count + begin;
635                 boundary_count = 0;
636              } else {
637                 s->data_count = block_size;
638                 boundary_count -= block_size - begin;
639             }
640             dma_memory_read(s->dma_as, s->sdmasysad,
641                             &s->fifo_buffer[begin], s->data_count - begin);
642             s->sdmasysad += s->data_count - begin;
643             if (s->data_count == block_size) {
644                 sdbus_write_data(&s->sdbus, s->fifo_buffer, block_size);
645                 s->data_count = 0;
646                 if (s->trnmod & SDHC_TRNS_BLK_CNT_EN) {
647                     s->blkcnt--;
648                 }
649             }
650             if (page_aligned && boundary_count == 0) {
651                 break;
652             }
653         }
654     }
655 
656     if (s->blkcnt == 0) {
657         sdhci_end_transfer(s);
658     } else {
659         if (s->norintstsen & SDHC_NISEN_DMA) {
660             s->norintsts |= SDHC_NIS_DMA;
661         }
662         sdhci_update_irq(s);
663     }
664 }
665 
666 /* single block SDMA transfer */
667 static void sdhci_sdma_transfer_single_block(SDHCIState *s)
668 {
669     uint32_t datacnt = s->blksize & BLOCK_SIZE_MASK;
670 
671     if (s->trnmod & SDHC_TRNS_READ) {
672         sdbus_read_data(&s->sdbus, s->fifo_buffer, datacnt);
673         dma_memory_write(s->dma_as, s->sdmasysad, s->fifo_buffer, datacnt);
674     } else {
675         dma_memory_read(s->dma_as, s->sdmasysad, s->fifo_buffer, datacnt);
676         sdbus_write_data(&s->sdbus, s->fifo_buffer, datacnt);
677     }
678     s->blkcnt--;
679 
680     sdhci_end_transfer(s);
681 }
682 
683 typedef struct ADMADescr {
684     hwaddr addr;
685     uint16_t length;
686     uint8_t attr;
687     uint8_t incr;
688 } ADMADescr;
689 
690 static void get_adma_description(SDHCIState *s, ADMADescr *dscr)
691 {
692     uint32_t adma1 = 0;
693     uint64_t adma2 = 0;
694     hwaddr entry_addr = (hwaddr)s->admasysaddr;
695     switch (SDHC_DMA_TYPE(s->hostctl1)) {
696     case SDHC_CTRL_ADMA2_32:
697         dma_memory_read(s->dma_as, entry_addr, &adma2, sizeof(adma2));
698         adma2 = le64_to_cpu(adma2);
699         /* The spec does not specify endianness of descriptor table.
700          * We currently assume that it is LE.
701          */
702         dscr->addr = (hwaddr)extract64(adma2, 32, 32) & ~0x3ull;
703         dscr->length = (uint16_t)extract64(adma2, 16, 16);
704         dscr->attr = (uint8_t)extract64(adma2, 0, 7);
705         dscr->incr = 8;
706         break;
707     case SDHC_CTRL_ADMA1_32:
708         dma_memory_read(s->dma_as, entry_addr, &adma1, sizeof(adma1));
709         adma1 = le32_to_cpu(adma1);
710         dscr->addr = (hwaddr)(adma1 & 0xFFFFF000);
711         dscr->attr = (uint8_t)extract32(adma1, 0, 7);
712         dscr->incr = 4;
713         if ((dscr->attr & SDHC_ADMA_ATTR_ACT_MASK) == SDHC_ADMA_ATTR_SET_LEN) {
714             dscr->length = (uint16_t)extract32(adma1, 12, 16);
715         } else {
716             dscr->length = 4 * KiB;
717         }
718         break;
719     case SDHC_CTRL_ADMA2_64:
720         dma_memory_read(s->dma_as, entry_addr, &dscr->attr, 1);
721         dma_memory_read(s->dma_as, entry_addr + 2, &dscr->length, 2);
722         dscr->length = le16_to_cpu(dscr->length);
723         dma_memory_read(s->dma_as, entry_addr + 4, &dscr->addr, 8);
724         dscr->addr = le64_to_cpu(dscr->addr);
725         dscr->attr &= (uint8_t) ~0xC0;
726         dscr->incr = 12;
727         break;
728     }
729 }
730 
731 /* Advanced DMA data transfer */
732 
733 static void sdhci_do_adma(SDHCIState *s)
734 {
735     unsigned int begin, length;
736     const uint16_t block_size = s->blksize & BLOCK_SIZE_MASK;
737     ADMADescr dscr = {};
738     int i;
739 
740     if (s->trnmod & SDHC_TRNS_BLK_CNT_EN && !s->blkcnt) {
741         /* Stop Multiple Transfer */
742         sdhci_end_transfer(s);
743         return;
744     }
745 
746     for (i = 0; i < SDHC_ADMA_DESCS_PER_DELAY; ++i) {
747         s->admaerr &= ~SDHC_ADMAERR_LENGTH_MISMATCH;
748 
749         get_adma_description(s, &dscr);
750         trace_sdhci_adma_loop(dscr.addr, dscr.length, dscr.attr);
751 
752         if ((dscr.attr & SDHC_ADMA_ATTR_VALID) == 0) {
753             /* Indicate that error occurred in ST_FDS state */
754             s->admaerr &= ~SDHC_ADMAERR_STATE_MASK;
755             s->admaerr |= SDHC_ADMAERR_STATE_ST_FDS;
756 
757             /* Generate ADMA error interrupt */
758             if (s->errintstsen & SDHC_EISEN_ADMAERR) {
759                 s->errintsts |= SDHC_EIS_ADMAERR;
760                 s->norintsts |= SDHC_NIS_ERR;
761             }
762 
763             sdhci_update_irq(s);
764             return;
765         }
766 
767         length = dscr.length ? dscr.length : 64 * KiB;
768 
769         switch (dscr.attr & SDHC_ADMA_ATTR_ACT_MASK) {
770         case SDHC_ADMA_ATTR_ACT_TRAN:  /* data transfer */
771             s->prnsts |= SDHC_DATA_INHIBIT | SDHC_DAT_LINE_ACTIVE;
772             if (s->trnmod & SDHC_TRNS_READ) {
773                 s->prnsts |= SDHC_DOING_READ;
774                 while (length) {
775                     if (s->data_count == 0) {
776                         sdbus_read_data(&s->sdbus, s->fifo_buffer, block_size);
777                     }
778                     begin = s->data_count;
779                     if ((length + begin) < block_size) {
780                         s->data_count = length + begin;
781                         length = 0;
782                      } else {
783                         s->data_count = block_size;
784                         length -= block_size - begin;
785                     }
786                     dma_memory_write(s->dma_as, dscr.addr,
787                                      &s->fifo_buffer[begin],
788                                      s->data_count - begin);
789                     dscr.addr += s->data_count - begin;
790                     if (s->data_count == block_size) {
791                         s->data_count = 0;
792                         if (s->trnmod & SDHC_TRNS_BLK_CNT_EN) {
793                             s->blkcnt--;
794                             if (s->blkcnt == 0) {
795                                 break;
796                             }
797                         }
798                     }
799                 }
800             } else {
801                 s->prnsts |= SDHC_DOING_WRITE;
802                 while (length) {
803                     begin = s->data_count;
804                     if ((length + begin) < block_size) {
805                         s->data_count = length + begin;
806                         length = 0;
807                      } else {
808                         s->data_count = block_size;
809                         length -= block_size - begin;
810                     }
811                     dma_memory_read(s->dma_as, dscr.addr,
812                                     &s->fifo_buffer[begin],
813                                     s->data_count - begin);
814                     dscr.addr += s->data_count - begin;
815                     if (s->data_count == block_size) {
816                         sdbus_write_data(&s->sdbus, s->fifo_buffer, block_size);
817                         s->data_count = 0;
818                         if (s->trnmod & SDHC_TRNS_BLK_CNT_EN) {
819                             s->blkcnt--;
820                             if (s->blkcnt == 0) {
821                                 break;
822                             }
823                         }
824                     }
825                 }
826             }
827             s->admasysaddr += dscr.incr;
828             break;
829         case SDHC_ADMA_ATTR_ACT_LINK:   /* link to next descriptor table */
830             s->admasysaddr = dscr.addr;
831             trace_sdhci_adma("link", s->admasysaddr);
832             break;
833         default:
834             s->admasysaddr += dscr.incr;
835             break;
836         }
837 
838         if (dscr.attr & SDHC_ADMA_ATTR_INT) {
839             trace_sdhci_adma("interrupt", s->admasysaddr);
840             if (s->norintstsen & SDHC_NISEN_DMA) {
841                 s->norintsts |= SDHC_NIS_DMA;
842             }
843 
844             if (sdhci_update_irq(s) && !(dscr.attr & SDHC_ADMA_ATTR_END)) {
845                 /* IRQ delivered, reschedule current transfer */
846                 break;
847             }
848         }
849 
850         /* ADMA transfer terminates if blkcnt == 0 or by END attribute */
851         if (((s->trnmod & SDHC_TRNS_BLK_CNT_EN) &&
852                     (s->blkcnt == 0)) || (dscr.attr & SDHC_ADMA_ATTR_END)) {
853             trace_sdhci_adma_transfer_completed();
854             if (length || ((dscr.attr & SDHC_ADMA_ATTR_END) &&
855                 (s->trnmod & SDHC_TRNS_BLK_CNT_EN) &&
856                 s->blkcnt != 0)) {
857                 trace_sdhci_error("SD/MMC host ADMA length mismatch");
858                 s->admaerr |= SDHC_ADMAERR_LENGTH_MISMATCH |
859                         SDHC_ADMAERR_STATE_ST_TFR;
860                 if (s->errintstsen & SDHC_EISEN_ADMAERR) {
861                     trace_sdhci_error("Set ADMA error flag");
862                     s->errintsts |= SDHC_EIS_ADMAERR;
863                     s->norintsts |= SDHC_NIS_ERR;
864                 }
865 
866                 sdhci_update_irq(s);
867             }
868             sdhci_end_transfer(s);
869             return;
870         }
871 
872     }
873 
874     /* we have unfinished business - reschedule to continue ADMA */
875     timer_mod(s->transfer_timer,
876                    qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + SDHC_TRANSFER_DELAY);
877 }
878 
879 /* Perform data transfer according to controller configuration */
880 
881 static void sdhci_data_transfer(void *opaque)
882 {
883     SDHCIState *s = (SDHCIState *)opaque;
884 
885     if (s->trnmod & SDHC_TRNS_DMA) {
886         switch (SDHC_DMA_TYPE(s->hostctl1)) {
887         case SDHC_CTRL_SDMA:
888             if ((s->blkcnt == 1) || !(s->trnmod & SDHC_TRNS_MULTI)) {
889                 sdhci_sdma_transfer_single_block(s);
890             } else {
891                 sdhci_sdma_transfer_multi_blocks(s);
892             }
893 
894             break;
895         case SDHC_CTRL_ADMA1_32:
896             if (!(s->capareg & R_SDHC_CAPAB_ADMA1_MASK)) {
897                 trace_sdhci_error("ADMA1 not supported");
898                 break;
899             }
900 
901             sdhci_do_adma(s);
902             break;
903         case SDHC_CTRL_ADMA2_32:
904             if (!(s->capareg & R_SDHC_CAPAB_ADMA2_MASK)) {
905                 trace_sdhci_error("ADMA2 not supported");
906                 break;
907             }
908 
909             sdhci_do_adma(s);
910             break;
911         case SDHC_CTRL_ADMA2_64:
912             if (!(s->capareg & R_SDHC_CAPAB_ADMA2_MASK) ||
913                     !(s->capareg & R_SDHC_CAPAB_BUS64BIT_MASK)) {
914                 trace_sdhci_error("64 bit ADMA not supported");
915                 break;
916             }
917 
918             sdhci_do_adma(s);
919             break;
920         default:
921             trace_sdhci_error("Unsupported DMA type");
922             break;
923         }
924     } else {
925         if ((s->trnmod & SDHC_TRNS_READ) && sdbus_data_ready(&s->sdbus)) {
926             s->prnsts |= SDHC_DOING_READ | SDHC_DATA_INHIBIT |
927                     SDHC_DAT_LINE_ACTIVE;
928             sdhci_read_block_from_card(s);
929         } else {
930             s->prnsts |= SDHC_DOING_WRITE | SDHC_DAT_LINE_ACTIVE |
931                     SDHC_SPACE_AVAILABLE | SDHC_DATA_INHIBIT;
932             sdhci_write_block_to_card(s);
933         }
934     }
935 }
936 
937 static bool sdhci_can_issue_command(SDHCIState *s)
938 {
939     if (!SDHC_CLOCK_IS_ON(s->clkcon) ||
940         (((s->prnsts & SDHC_DATA_INHIBIT) || s->stopped_state) &&
941         ((s->cmdreg & SDHC_CMD_DATA_PRESENT) ||
942         ((s->cmdreg & SDHC_CMD_RESPONSE) == SDHC_CMD_RSP_WITH_BUSY &&
943         !(SDHC_COMMAND_TYPE(s->cmdreg) == SDHC_CMD_ABORT))))) {
944         return false;
945     }
946 
947     return true;
948 }
949 
950 /* The Buffer Data Port register must be accessed in sequential and
951  * continuous manner */
952 static inline bool
953 sdhci_buff_access_is_sequential(SDHCIState *s, unsigned byte_num)
954 {
955     if ((s->data_count & 0x3) != byte_num) {
956         trace_sdhci_error("Non-sequential access to Buffer Data Port register"
957                           "is prohibited\n");
958         return false;
959     }
960     return true;
961 }
962 
963 static void sdhci_resume_pending_transfer(SDHCIState *s)
964 {
965     timer_del(s->transfer_timer);
966     sdhci_data_transfer(s);
967 }
968 
969 static uint64_t sdhci_read(void *opaque, hwaddr offset, unsigned size)
970 {
971     SDHCIState *s = (SDHCIState *)opaque;
972     uint32_t ret = 0;
973 
974     if (timer_pending(s->transfer_timer)) {
975         sdhci_resume_pending_transfer(s);
976     }
977 
978     switch (offset & ~0x3) {
979     case SDHC_SYSAD:
980         ret = s->sdmasysad;
981         break;
982     case SDHC_BLKSIZE:
983         ret = s->blksize | (s->blkcnt << 16);
984         break;
985     case SDHC_ARGUMENT:
986         ret = s->argument;
987         break;
988     case SDHC_TRNMOD:
989         ret = s->trnmod | (s->cmdreg << 16);
990         break;
991     case SDHC_RSPREG0 ... SDHC_RSPREG3:
992         ret = s->rspreg[((offset & ~0x3) - SDHC_RSPREG0) >> 2];
993         break;
994     case  SDHC_BDATA:
995         if (sdhci_buff_access_is_sequential(s, offset - SDHC_BDATA)) {
996             ret = sdhci_read_dataport(s, size);
997             trace_sdhci_access("rd", size << 3, offset, "->", ret, ret);
998             return ret;
999         }
1000         break;
1001     case SDHC_PRNSTS:
1002         ret = s->prnsts;
1003         ret = FIELD_DP32(ret, SDHC_PRNSTS, DAT_LVL,
1004                          sdbus_get_dat_lines(&s->sdbus));
1005         ret = FIELD_DP32(ret, SDHC_PRNSTS, CMD_LVL,
1006                          sdbus_get_cmd_line(&s->sdbus));
1007         break;
1008     case SDHC_HOSTCTL:
1009         ret = s->hostctl1 | (s->pwrcon << 8) | (s->blkgap << 16) |
1010               (s->wakcon << 24);
1011         break;
1012     case SDHC_CLKCON:
1013         ret = s->clkcon | (s->timeoutcon << 16);
1014         break;
1015     case SDHC_NORINTSTS:
1016         ret = s->norintsts | (s->errintsts << 16);
1017         break;
1018     case SDHC_NORINTSTSEN:
1019         ret = s->norintstsen | (s->errintstsen << 16);
1020         break;
1021     case SDHC_NORINTSIGEN:
1022         ret = s->norintsigen | (s->errintsigen << 16);
1023         break;
1024     case SDHC_ACMD12ERRSTS:
1025         ret = s->acmd12errsts | (s->hostctl2 << 16);
1026         break;
1027     case SDHC_CAPAB:
1028         ret = (uint32_t)s->capareg;
1029         break;
1030     case SDHC_CAPAB + 4:
1031         ret = (uint32_t)(s->capareg >> 32);
1032         break;
1033     case SDHC_MAXCURR:
1034         ret = (uint32_t)s->maxcurr;
1035         break;
1036     case SDHC_MAXCURR + 4:
1037         ret = (uint32_t)(s->maxcurr >> 32);
1038         break;
1039     case SDHC_ADMAERR:
1040         ret =  s->admaerr;
1041         break;
1042     case SDHC_ADMASYSADDR:
1043         ret = (uint32_t)s->admasysaddr;
1044         break;
1045     case SDHC_ADMASYSADDR + 4:
1046         ret = (uint32_t)(s->admasysaddr >> 32);
1047         break;
1048     case SDHC_SLOT_INT_STATUS:
1049         ret = (s->version << 16) | sdhci_slotint(s);
1050         break;
1051     default:
1052         qemu_log_mask(LOG_UNIMP, "SDHC rd_%ub @0x%02" HWADDR_PRIx " "
1053                       "not implemented\n", size, offset);
1054         break;
1055     }
1056 
1057     ret >>= (offset & 0x3) * 8;
1058     ret &= (1ULL << (size * 8)) - 1;
1059     trace_sdhci_access("rd", size << 3, offset, "->", ret, ret);
1060     return ret;
1061 }
1062 
1063 static inline void sdhci_blkgap_write(SDHCIState *s, uint8_t value)
1064 {
1065     if ((value & SDHC_STOP_AT_GAP_REQ) && (s->blkgap & SDHC_STOP_AT_GAP_REQ)) {
1066         return;
1067     }
1068     s->blkgap = value & SDHC_STOP_AT_GAP_REQ;
1069 
1070     if ((value & SDHC_CONTINUE_REQ) && s->stopped_state &&
1071             (s->blkgap & SDHC_STOP_AT_GAP_REQ) == 0) {
1072         if (s->stopped_state == sdhc_gap_read) {
1073             s->prnsts |= SDHC_DAT_LINE_ACTIVE | SDHC_DOING_READ;
1074             sdhci_read_block_from_card(s);
1075         } else {
1076             s->prnsts |= SDHC_DAT_LINE_ACTIVE | SDHC_DOING_WRITE;
1077             sdhci_write_block_to_card(s);
1078         }
1079         s->stopped_state = sdhc_not_stopped;
1080     } else if (!s->stopped_state && (value & SDHC_STOP_AT_GAP_REQ)) {
1081         if (s->prnsts & SDHC_DOING_READ) {
1082             s->stopped_state = sdhc_gap_read;
1083         } else if (s->prnsts & SDHC_DOING_WRITE) {
1084             s->stopped_state = sdhc_gap_write;
1085         }
1086     }
1087 }
1088 
1089 static inline void sdhci_reset_write(SDHCIState *s, uint8_t value)
1090 {
1091     switch (value) {
1092     case SDHC_RESET_ALL:
1093         sdhci_reset(s);
1094         break;
1095     case SDHC_RESET_CMD:
1096         s->prnsts &= ~SDHC_CMD_INHIBIT;
1097         s->norintsts &= ~SDHC_NIS_CMDCMP;
1098         break;
1099     case SDHC_RESET_DATA:
1100         s->data_count = 0;
1101         s->prnsts &= ~(SDHC_SPACE_AVAILABLE | SDHC_DATA_AVAILABLE |
1102                 SDHC_DOING_READ | SDHC_DOING_WRITE |
1103                 SDHC_DATA_INHIBIT | SDHC_DAT_LINE_ACTIVE);
1104         s->blkgap &= ~(SDHC_STOP_AT_GAP_REQ | SDHC_CONTINUE_REQ);
1105         s->stopped_state = sdhc_not_stopped;
1106         s->norintsts &= ~(SDHC_NIS_WBUFRDY | SDHC_NIS_RBUFRDY |
1107                 SDHC_NIS_DMA | SDHC_NIS_TRSCMP | SDHC_NIS_BLKGAP);
1108         break;
1109     }
1110 }
1111 
1112 static void
1113 sdhci_write(void *opaque, hwaddr offset, uint64_t val, unsigned size)
1114 {
1115     SDHCIState *s = (SDHCIState *)opaque;
1116     unsigned shift =  8 * (offset & 0x3);
1117     uint32_t mask = ~(((1ULL << (size * 8)) - 1) << shift);
1118     uint32_t value = val;
1119     value <<= shift;
1120 
1121     if (timer_pending(s->transfer_timer)) {
1122         sdhci_resume_pending_transfer(s);
1123     }
1124 
1125     switch (offset & ~0x3) {
1126     case SDHC_SYSAD:
1127         if (!TRANSFERRING_DATA(s->prnsts)) {
1128             s->sdmasysad = (s->sdmasysad & mask) | value;
1129             MASKED_WRITE(s->sdmasysad, mask, value);
1130             /* Writing to last byte of sdmasysad might trigger transfer */
1131             if (!(mask & 0xFF000000) && s->blkcnt && s->blksize &&
1132                 SDHC_DMA_TYPE(s->hostctl1) == SDHC_CTRL_SDMA) {
1133                 if (s->trnmod & SDHC_TRNS_MULTI) {
1134                     sdhci_sdma_transfer_multi_blocks(s);
1135                 } else {
1136                     sdhci_sdma_transfer_single_block(s);
1137                 }
1138             }
1139         }
1140         break;
1141     case SDHC_BLKSIZE:
1142         if (!TRANSFERRING_DATA(s->prnsts)) {
1143             uint16_t blksize = s->blksize;
1144 
1145             MASKED_WRITE(s->blksize, mask, extract32(value, 0, 12));
1146             MASKED_WRITE(s->blkcnt, mask >> 16, value >> 16);
1147 
1148             /* Limit block size to the maximum buffer size */
1149             if (extract32(s->blksize, 0, 12) > s->buf_maxsz) {
1150                 qemu_log_mask(LOG_GUEST_ERROR, "%s: Size 0x%x is larger than "
1151                               "the maximum buffer 0x%x\n", __func__, s->blksize,
1152                               s->buf_maxsz);
1153 
1154                 s->blksize = deposit32(s->blksize, 0, 12, s->buf_maxsz);
1155             }
1156 
1157             /*
1158              * If the block size is programmed to a different value from
1159              * the previous one, reset the data pointer of s->fifo_buffer[]
1160              * so that s->fifo_buffer[] can be filled in using the new block
1161              * size in the next transfer.
1162              */
1163             if (blksize != s->blksize) {
1164                 s->data_count = 0;
1165             }
1166         }
1167 
1168         break;
1169     case SDHC_ARGUMENT:
1170         MASKED_WRITE(s->argument, mask, value);
1171         break;
1172     case SDHC_TRNMOD:
1173         /* DMA can be enabled only if it is supported as indicated by
1174          * capabilities register */
1175         if (!(s->capareg & R_SDHC_CAPAB_SDMA_MASK)) {
1176             value &= ~SDHC_TRNS_DMA;
1177         }
1178         MASKED_WRITE(s->trnmod, mask, value & SDHC_TRNMOD_MASK);
1179         MASKED_WRITE(s->cmdreg, mask >> 16, value >> 16);
1180 
1181         /* Writing to the upper byte of CMDREG triggers SD command generation */
1182         if ((mask & 0xFF000000) || !sdhci_can_issue_command(s)) {
1183             break;
1184         }
1185 
1186         sdhci_send_command(s);
1187         break;
1188     case  SDHC_BDATA:
1189         if (sdhci_buff_access_is_sequential(s, offset - SDHC_BDATA)) {
1190             sdhci_write_dataport(s, value >> shift, size);
1191         }
1192         break;
1193     case SDHC_HOSTCTL:
1194         if (!(mask & 0xFF0000)) {
1195             sdhci_blkgap_write(s, value >> 16);
1196         }
1197         MASKED_WRITE(s->hostctl1, mask, value);
1198         MASKED_WRITE(s->pwrcon, mask >> 8, value >> 8);
1199         MASKED_WRITE(s->wakcon, mask >> 24, value >> 24);
1200         if (!(s->prnsts & SDHC_CARD_PRESENT) || ((s->pwrcon >> 1) & 0x7) < 5 ||
1201                 !(s->capareg & (1 << (31 - ((s->pwrcon >> 1) & 0x7))))) {
1202             s->pwrcon &= ~SDHC_POWER_ON;
1203         }
1204         break;
1205     case SDHC_CLKCON:
1206         if (!(mask & 0xFF000000)) {
1207             sdhci_reset_write(s, value >> 24);
1208         }
1209         MASKED_WRITE(s->clkcon, mask, value);
1210         MASKED_WRITE(s->timeoutcon, mask >> 16, value >> 16);
1211         if (s->clkcon & SDHC_CLOCK_INT_EN) {
1212             s->clkcon |= SDHC_CLOCK_INT_STABLE;
1213         } else {
1214             s->clkcon &= ~SDHC_CLOCK_INT_STABLE;
1215         }
1216         break;
1217     case SDHC_NORINTSTS:
1218         if (s->norintstsen & SDHC_NISEN_CARDINT) {
1219             value &= ~SDHC_NIS_CARDINT;
1220         }
1221         s->norintsts &= mask | ~value;
1222         s->errintsts &= (mask >> 16) | ~(value >> 16);
1223         if (s->errintsts) {
1224             s->norintsts |= SDHC_NIS_ERR;
1225         } else {
1226             s->norintsts &= ~SDHC_NIS_ERR;
1227         }
1228         sdhci_update_irq(s);
1229         break;
1230     case SDHC_NORINTSTSEN:
1231         MASKED_WRITE(s->norintstsen, mask, value);
1232         MASKED_WRITE(s->errintstsen, mask >> 16, value >> 16);
1233         s->norintsts &= s->norintstsen;
1234         s->errintsts &= s->errintstsen;
1235         if (s->errintsts) {
1236             s->norintsts |= SDHC_NIS_ERR;
1237         } else {
1238             s->norintsts &= ~SDHC_NIS_ERR;
1239         }
1240         /* Quirk for Raspberry Pi: pending card insert interrupt
1241          * appears when first enabled after power on */
1242         if ((s->norintstsen & SDHC_NISEN_INSERT) && s->pending_insert_state) {
1243             assert(s->pending_insert_quirk);
1244             s->norintsts |= SDHC_NIS_INSERT;
1245             s->pending_insert_state = false;
1246         }
1247         sdhci_update_irq(s);
1248         break;
1249     case SDHC_NORINTSIGEN:
1250         MASKED_WRITE(s->norintsigen, mask, value);
1251         MASKED_WRITE(s->errintsigen, mask >> 16, value >> 16);
1252         sdhci_update_irq(s);
1253         break;
1254     case SDHC_ADMAERR:
1255         MASKED_WRITE(s->admaerr, mask, value);
1256         break;
1257     case SDHC_ADMASYSADDR:
1258         s->admasysaddr = (s->admasysaddr & (0xFFFFFFFF00000000ULL |
1259                 (uint64_t)mask)) | (uint64_t)value;
1260         break;
1261     case SDHC_ADMASYSADDR + 4:
1262         s->admasysaddr = (s->admasysaddr & (0x00000000FFFFFFFFULL |
1263                 ((uint64_t)mask << 32))) | ((uint64_t)value << 32);
1264         break;
1265     case SDHC_FEAER:
1266         s->acmd12errsts |= value;
1267         s->errintsts |= (value >> 16) & s->errintstsen;
1268         if (s->acmd12errsts) {
1269             s->errintsts |= SDHC_EIS_CMD12ERR;
1270         }
1271         if (s->errintsts) {
1272             s->norintsts |= SDHC_NIS_ERR;
1273         }
1274         sdhci_update_irq(s);
1275         break;
1276     case SDHC_ACMD12ERRSTS:
1277         MASKED_WRITE(s->acmd12errsts, mask, value & UINT16_MAX);
1278         if (s->uhs_mode >= UHS_I) {
1279             MASKED_WRITE(s->hostctl2, mask >> 16, value >> 16);
1280 
1281             if (FIELD_EX32(s->hostctl2, SDHC_HOSTCTL2, V18_ENA)) {
1282                 sdbus_set_voltage(&s->sdbus, SD_VOLTAGE_1_8V);
1283             } else {
1284                 sdbus_set_voltage(&s->sdbus, SD_VOLTAGE_3_3V);
1285             }
1286         }
1287         break;
1288 
1289     case SDHC_CAPAB:
1290     case SDHC_CAPAB + 4:
1291     case SDHC_MAXCURR:
1292     case SDHC_MAXCURR + 4:
1293         qemu_log_mask(LOG_GUEST_ERROR, "SDHC wr_%ub @0x%02" HWADDR_PRIx
1294                       " <- 0x%08x read-only\n", size, offset, value >> shift);
1295         break;
1296 
1297     default:
1298         qemu_log_mask(LOG_UNIMP, "SDHC wr_%ub @0x%02" HWADDR_PRIx " <- 0x%08x "
1299                       "not implemented\n", size, offset, value >> shift);
1300         break;
1301     }
1302     trace_sdhci_access("wr", size << 3, offset, "<-",
1303                        value >> shift, value >> shift);
1304 }
1305 
1306 static const MemoryRegionOps sdhci_mmio_ops = {
1307     .read = sdhci_read,
1308     .write = sdhci_write,
1309     .valid = {
1310         .min_access_size = 1,
1311         .max_access_size = 4,
1312         .unaligned = false
1313     },
1314     .endianness = DEVICE_LITTLE_ENDIAN,
1315 };
1316 
1317 static void sdhci_init_readonly_registers(SDHCIState *s, Error **errp)
1318 {
1319     ERRP_GUARD();
1320 
1321     switch (s->sd_spec_version) {
1322     case 2 ... 3:
1323         break;
1324     default:
1325         error_setg(errp, "Only Spec v2/v3 are supported");
1326         return;
1327     }
1328     s->version = (SDHC_HCVER_VENDOR << 8) | (s->sd_spec_version - 1);
1329 
1330     sdhci_check_capareg(s, errp);
1331     if (*errp) {
1332         return;
1333     }
1334 }
1335 
1336 /* --- qdev common --- */
1337 
1338 void sdhci_initfn(SDHCIState *s)
1339 {
1340     qbus_create_inplace(&s->sdbus, sizeof(s->sdbus),
1341                         TYPE_SDHCI_BUS, DEVICE(s), "sd-bus");
1342 
1343     s->insert_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, sdhci_raise_insertion_irq, s);
1344     s->transfer_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, sdhci_data_transfer, s);
1345 
1346     s->io_ops = &sdhci_mmio_ops;
1347 }
1348 
1349 void sdhci_uninitfn(SDHCIState *s)
1350 {
1351     timer_free(s->insert_timer);
1352     timer_free(s->transfer_timer);
1353 
1354     g_free(s->fifo_buffer);
1355     s->fifo_buffer = NULL;
1356 }
1357 
1358 void sdhci_common_realize(SDHCIState *s, Error **errp)
1359 {
1360     ERRP_GUARD();
1361 
1362     sdhci_init_readonly_registers(s, errp);
1363     if (*errp) {
1364         return;
1365     }
1366     s->buf_maxsz = sdhci_get_fifolen(s);
1367     s->fifo_buffer = g_malloc0(s->buf_maxsz);
1368 
1369     memory_region_init_io(&s->iomem, OBJECT(s), s->io_ops, s, "sdhci",
1370                           SDHC_REGISTERS_MAP_SIZE);
1371 }
1372 
1373 void sdhci_common_unrealize(SDHCIState *s)
1374 {
1375     /* This function is expected to be called only once for each class:
1376      * - SysBus:    via DeviceClass->unrealize(),
1377      * - PCI:       via PCIDeviceClass->exit().
1378      * However to avoid double-free and/or use-after-free we still nullify
1379      * this variable (better safe than sorry!). */
1380     g_free(s->fifo_buffer);
1381     s->fifo_buffer = NULL;
1382 }
1383 
1384 static bool sdhci_pending_insert_vmstate_needed(void *opaque)
1385 {
1386     SDHCIState *s = opaque;
1387 
1388     return s->pending_insert_state;
1389 }
1390 
1391 static const VMStateDescription sdhci_pending_insert_vmstate = {
1392     .name = "sdhci/pending-insert",
1393     .version_id = 1,
1394     .minimum_version_id = 1,
1395     .needed = sdhci_pending_insert_vmstate_needed,
1396     .fields = (VMStateField[]) {
1397         VMSTATE_BOOL(pending_insert_state, SDHCIState),
1398         VMSTATE_END_OF_LIST()
1399     },
1400 };
1401 
1402 const VMStateDescription sdhci_vmstate = {
1403     .name = "sdhci",
1404     .version_id = 1,
1405     .minimum_version_id = 1,
1406     .fields = (VMStateField[]) {
1407         VMSTATE_UINT32(sdmasysad, SDHCIState),
1408         VMSTATE_UINT16(blksize, SDHCIState),
1409         VMSTATE_UINT16(blkcnt, SDHCIState),
1410         VMSTATE_UINT32(argument, SDHCIState),
1411         VMSTATE_UINT16(trnmod, SDHCIState),
1412         VMSTATE_UINT16(cmdreg, SDHCIState),
1413         VMSTATE_UINT32_ARRAY(rspreg, SDHCIState, 4),
1414         VMSTATE_UINT32(prnsts, SDHCIState),
1415         VMSTATE_UINT8(hostctl1, SDHCIState),
1416         VMSTATE_UINT8(pwrcon, SDHCIState),
1417         VMSTATE_UINT8(blkgap, SDHCIState),
1418         VMSTATE_UINT8(wakcon, SDHCIState),
1419         VMSTATE_UINT16(clkcon, SDHCIState),
1420         VMSTATE_UINT8(timeoutcon, SDHCIState),
1421         VMSTATE_UINT8(admaerr, SDHCIState),
1422         VMSTATE_UINT16(norintsts, SDHCIState),
1423         VMSTATE_UINT16(errintsts, SDHCIState),
1424         VMSTATE_UINT16(norintstsen, SDHCIState),
1425         VMSTATE_UINT16(errintstsen, SDHCIState),
1426         VMSTATE_UINT16(norintsigen, SDHCIState),
1427         VMSTATE_UINT16(errintsigen, SDHCIState),
1428         VMSTATE_UINT16(acmd12errsts, SDHCIState),
1429         VMSTATE_UINT16(data_count, SDHCIState),
1430         VMSTATE_UINT64(admasysaddr, SDHCIState),
1431         VMSTATE_UINT8(stopped_state, SDHCIState),
1432         VMSTATE_VBUFFER_UINT32(fifo_buffer, SDHCIState, 1, NULL, buf_maxsz),
1433         VMSTATE_TIMER_PTR(insert_timer, SDHCIState),
1434         VMSTATE_TIMER_PTR(transfer_timer, SDHCIState),
1435         VMSTATE_END_OF_LIST()
1436     },
1437     .subsections = (const VMStateDescription*[]) {
1438         &sdhci_pending_insert_vmstate,
1439         NULL
1440     },
1441 };
1442 
1443 void sdhci_common_class_init(ObjectClass *klass, void *data)
1444 {
1445     DeviceClass *dc = DEVICE_CLASS(klass);
1446 
1447     set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
1448     dc->vmsd = &sdhci_vmstate;
1449     dc->reset = sdhci_poweron_reset;
1450 }
1451 
1452 /* --- qdev SysBus --- */
1453 
1454 static Property sdhci_sysbus_properties[] = {
1455     DEFINE_SDHCI_COMMON_PROPERTIES(SDHCIState),
1456     DEFINE_PROP_BOOL("pending-insert-quirk", SDHCIState, pending_insert_quirk,
1457                      false),
1458     DEFINE_PROP_LINK("dma", SDHCIState,
1459                      dma_mr, TYPE_MEMORY_REGION, MemoryRegion *),
1460     DEFINE_PROP_END_OF_LIST(),
1461 };
1462 
1463 static void sdhci_sysbus_init(Object *obj)
1464 {
1465     SDHCIState *s = SYSBUS_SDHCI(obj);
1466 
1467     sdhci_initfn(s);
1468 }
1469 
1470 static void sdhci_sysbus_finalize(Object *obj)
1471 {
1472     SDHCIState *s = SYSBUS_SDHCI(obj);
1473 
1474     if (s->dma_mr) {
1475         object_unparent(OBJECT(s->dma_mr));
1476     }
1477 
1478     sdhci_uninitfn(s);
1479 }
1480 
1481 static void sdhci_sysbus_realize(DeviceState *dev, Error **errp)
1482 {
1483     ERRP_GUARD();
1484     SDHCIState *s = SYSBUS_SDHCI(dev);
1485     SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
1486 
1487     sdhci_common_realize(s, errp);
1488     if (*errp) {
1489         return;
1490     }
1491 
1492     if (s->dma_mr) {
1493         s->dma_as = &s->sysbus_dma_as;
1494         address_space_init(s->dma_as, s->dma_mr, "sdhci-dma");
1495     } else {
1496         /* use system_memory() if property "dma" not set */
1497         s->dma_as = &address_space_memory;
1498     }
1499 
1500     sysbus_init_irq(sbd, &s->irq);
1501 
1502     sysbus_init_mmio(sbd, &s->iomem);
1503 }
1504 
1505 static void sdhci_sysbus_unrealize(DeviceState *dev)
1506 {
1507     SDHCIState *s = SYSBUS_SDHCI(dev);
1508 
1509     sdhci_common_unrealize(s);
1510 
1511      if (s->dma_mr) {
1512         address_space_destroy(s->dma_as);
1513     }
1514 }
1515 
1516 static void sdhci_sysbus_class_init(ObjectClass *klass, void *data)
1517 {
1518     DeviceClass *dc = DEVICE_CLASS(klass);
1519 
1520     device_class_set_props(dc, sdhci_sysbus_properties);
1521     dc->realize = sdhci_sysbus_realize;
1522     dc->unrealize = sdhci_sysbus_unrealize;
1523 
1524     sdhci_common_class_init(klass, data);
1525 }
1526 
1527 static const TypeInfo sdhci_sysbus_info = {
1528     .name = TYPE_SYSBUS_SDHCI,
1529     .parent = TYPE_SYS_BUS_DEVICE,
1530     .instance_size = sizeof(SDHCIState),
1531     .instance_init = sdhci_sysbus_init,
1532     .instance_finalize = sdhci_sysbus_finalize,
1533     .class_init = sdhci_sysbus_class_init,
1534 };
1535 
1536 /* --- qdev bus master --- */
1537 
1538 static void sdhci_bus_class_init(ObjectClass *klass, void *data)
1539 {
1540     SDBusClass *sbc = SD_BUS_CLASS(klass);
1541 
1542     sbc->set_inserted = sdhci_set_inserted;
1543     sbc->set_readonly = sdhci_set_readonly;
1544 }
1545 
1546 static const TypeInfo sdhci_bus_info = {
1547     .name = TYPE_SDHCI_BUS,
1548     .parent = TYPE_SD_BUS,
1549     .instance_size = sizeof(SDBus),
1550     .class_init = sdhci_bus_class_init,
1551 };
1552 
1553 /* --- qdev i.MX eSDHC --- */
1554 
1555 static uint64_t usdhc_read(void *opaque, hwaddr offset, unsigned size)
1556 {
1557     SDHCIState *s = SYSBUS_SDHCI(opaque);
1558     uint32_t ret;
1559     uint16_t hostctl1;
1560 
1561     switch (offset) {
1562     default:
1563         return sdhci_read(opaque, offset, size);
1564 
1565     case SDHC_HOSTCTL:
1566         /*
1567          * For a detailed explanation on the following bit
1568          * manipulation code see comments in a similar part of
1569          * usdhc_write()
1570          */
1571         hostctl1 = SDHC_DMA_TYPE(s->hostctl1) << (8 - 3);
1572 
1573         if (s->hostctl1 & SDHC_CTRL_8BITBUS) {
1574             hostctl1 |= ESDHC_CTRL_8BITBUS;
1575         }
1576 
1577         if (s->hostctl1 & SDHC_CTRL_4BITBUS) {
1578             hostctl1 |= ESDHC_CTRL_4BITBUS;
1579         }
1580 
1581         ret  = hostctl1;
1582         ret |= (uint32_t)s->blkgap << 16;
1583         ret |= (uint32_t)s->wakcon << 24;
1584 
1585         break;
1586 
1587     case SDHC_PRNSTS:
1588         /* Add SDSTB (SD Clock Stable) bit to PRNSTS */
1589         ret = sdhci_read(opaque, offset, size) & ~ESDHC_PRNSTS_SDSTB;
1590         if (s->clkcon & SDHC_CLOCK_INT_STABLE) {
1591             ret |= ESDHC_PRNSTS_SDSTB;
1592         }
1593         break;
1594 
1595     case ESDHC_VENDOR_SPEC:
1596         ret = s->vendor_spec;
1597         break;
1598     case ESDHC_DLL_CTRL:
1599     case ESDHC_TUNE_CTRL_STATUS:
1600     case ESDHC_UNDOCUMENTED_REG27:
1601     case ESDHC_TUNING_CTRL:
1602     case ESDHC_MIX_CTRL:
1603     case ESDHC_WTMK_LVL:
1604         ret = 0;
1605         break;
1606     }
1607 
1608     return ret;
1609 }
1610 
1611 static void
1612 usdhc_write(void *opaque, hwaddr offset, uint64_t val, unsigned size)
1613 {
1614     SDHCIState *s = SYSBUS_SDHCI(opaque);
1615     uint8_t hostctl1;
1616     uint32_t value = (uint32_t)val;
1617 
1618     switch (offset) {
1619     case ESDHC_DLL_CTRL:
1620     case ESDHC_TUNE_CTRL_STATUS:
1621     case ESDHC_UNDOCUMENTED_REG27:
1622     case ESDHC_TUNING_CTRL:
1623     case ESDHC_WTMK_LVL:
1624         break;
1625 
1626     case ESDHC_VENDOR_SPEC:
1627         s->vendor_spec = value;
1628         switch (s->vendor) {
1629         case SDHCI_VENDOR_IMX:
1630             if (value & ESDHC_IMX_FRC_SDCLK_ON) {
1631                 s->prnsts &= ~SDHC_IMX_CLOCK_GATE_OFF;
1632             } else {
1633                 s->prnsts |= SDHC_IMX_CLOCK_GATE_OFF;
1634             }
1635             break;
1636         default:
1637             break;
1638         }
1639         break;
1640 
1641     case SDHC_HOSTCTL:
1642         /*
1643          * Here's What ESDHCI has at offset 0x28 (SDHC_HOSTCTL)
1644          *
1645          *       7         6     5      4      3      2        1      0
1646          * |-----------+--------+--------+-----------+----------+---------|
1647          * | Card      | Card   | Endian | DATA3     | Data     | Led     |
1648          * | Detect    | Detect | Mode   | as Card   | Transfer | Control |
1649          * | Signal    | Test   |        | Detection | Width    |         |
1650          * | Selection | Level  |        | Pin       |          |         |
1651          * |-----------+--------+--------+-----------+----------+---------|
1652          *
1653          * and 0x29
1654          *
1655          *  15      10 9    8
1656          * |----------+------|
1657          * | Reserved | DMA  |
1658          * |          | Sel. |
1659          * |          |      |
1660          * |----------+------|
1661          *
1662          * and here's what SDCHI spec expects those offsets to be:
1663          *
1664          * 0x28 (Host Control Register)
1665          *
1666          *     7        6         5       4  3      2         1        0
1667          * |--------+--------+----------+------+--------+----------+---------|
1668          * | Card   | Card   | Extended | DMA  | High   | Data     | LED     |
1669          * | Detect | Detect | Data     | Sel. | Speed  | Transfer | Control |
1670          * | Signal | Test   | Transfer |      | Enable | Width    |         |
1671          * | Sel.   | Level  | Width    |      |        |          |         |
1672          * |--------+--------+----------+------+--------+----------+---------|
1673          *
1674          * and 0x29 (Power Control Register)
1675          *
1676          * |----------------------------------|
1677          * | Power Control Register           |
1678          * |                                  |
1679          * | Description omitted,             |
1680          * | since it has no analog in ESDHCI |
1681          * |                                  |
1682          * |----------------------------------|
1683          *
1684          * Since offsets 0x2A and 0x2B should be compatible between
1685          * both IP specs we only need to reconcile least 16-bit of the
1686          * word we've been given.
1687          */
1688 
1689         /*
1690          * First, save bits 7 6 and 0 since they are identical
1691          */
1692         hostctl1 = value & (SDHC_CTRL_LED |
1693                             SDHC_CTRL_CDTEST_INS |
1694                             SDHC_CTRL_CDTEST_EN);
1695         /*
1696          * Second, split "Data Transfer Width" from bits 2 and 1 in to
1697          * bits 5 and 1
1698          */
1699         if (value & ESDHC_CTRL_8BITBUS) {
1700             hostctl1 |= SDHC_CTRL_8BITBUS;
1701         }
1702 
1703         if (value & ESDHC_CTRL_4BITBUS) {
1704             hostctl1 |= ESDHC_CTRL_4BITBUS;
1705         }
1706 
1707         /*
1708          * Third, move DMA select from bits 9 and 8 to bits 4 and 3
1709          */
1710         hostctl1 |= SDHC_DMA_TYPE(value >> (8 - 3));
1711 
1712         /*
1713          * Now place the corrected value into low 16-bit of the value
1714          * we are going to give standard SDHCI write function
1715          *
1716          * NOTE: This transformation should be the inverse of what can
1717          * be found in drivers/mmc/host/sdhci-esdhc-imx.c in Linux
1718          * kernel
1719          */
1720         value &= ~UINT16_MAX;
1721         value |= hostctl1;
1722         value |= (uint16_t)s->pwrcon << 8;
1723 
1724         sdhci_write(opaque, offset, value, size);
1725         break;
1726 
1727     case ESDHC_MIX_CTRL:
1728         /*
1729          * So, when SD/MMC stack in Linux tries to write to "Transfer
1730          * Mode Register", ESDHC i.MX quirk code will translate it
1731          * into a write to ESDHC_MIX_CTRL, so we do the opposite in
1732          * order to get where we started
1733          *
1734          * Note that Auto CMD23 Enable bit is located in a wrong place
1735          * on i.MX, but since it is not used by QEMU we do not care.
1736          *
1737          * We don't want to call sdhci_write(.., SDHC_TRNMOD, ...)
1738          * here becuase it will result in a call to
1739          * sdhci_send_command(s) which we don't want.
1740          *
1741          */
1742         s->trnmod = value & UINT16_MAX;
1743         break;
1744     case SDHC_TRNMOD:
1745         /*
1746          * Similar to above, but this time a write to "Command
1747          * Register" will be translated into a 4-byte write to
1748          * "Transfer Mode register" where lower 16-bit of value would
1749          * be set to zero. So what we do is fill those bits with
1750          * cached value from s->trnmod and let the SDHCI
1751          * infrastructure handle the rest
1752          */
1753         sdhci_write(opaque, offset, val | s->trnmod, size);
1754         break;
1755     case SDHC_BLKSIZE:
1756         /*
1757          * ESDHCI does not implement "Host SDMA Buffer Boundary", and
1758          * Linux driver will try to zero this field out which will
1759          * break the rest of SDHCI emulation.
1760          *
1761          * Linux defaults to maximum possible setting (512K boundary)
1762          * and it seems to be the only option that i.MX IP implements,
1763          * so we artificially set it to that value.
1764          */
1765         val |= 0x7 << 12;
1766         /* FALLTHROUGH */
1767     default:
1768         sdhci_write(opaque, offset, val, size);
1769         break;
1770     }
1771 }
1772 
1773 static const MemoryRegionOps usdhc_mmio_ops = {
1774     .read = usdhc_read,
1775     .write = usdhc_write,
1776     .valid = {
1777         .min_access_size = 1,
1778         .max_access_size = 4,
1779         .unaligned = false
1780     },
1781     .endianness = DEVICE_LITTLE_ENDIAN,
1782 };
1783 
1784 static void imx_usdhc_init(Object *obj)
1785 {
1786     SDHCIState *s = SYSBUS_SDHCI(obj);
1787 
1788     s->io_ops = &usdhc_mmio_ops;
1789     s->quirks = SDHCI_QUIRK_NO_BUSY_IRQ;
1790 }
1791 
1792 static const TypeInfo imx_usdhc_info = {
1793     .name = TYPE_IMX_USDHC,
1794     .parent = TYPE_SYSBUS_SDHCI,
1795     .instance_init = imx_usdhc_init,
1796 };
1797 
1798 /* --- qdev Samsung s3c --- */
1799 
1800 #define S3C_SDHCI_CONTROL2      0x80
1801 #define S3C_SDHCI_CONTROL3      0x84
1802 #define S3C_SDHCI_CONTROL4      0x8c
1803 
1804 static uint64_t sdhci_s3c_read(void *opaque, hwaddr offset, unsigned size)
1805 {
1806     uint64_t ret;
1807 
1808     switch (offset) {
1809     case S3C_SDHCI_CONTROL2:
1810     case S3C_SDHCI_CONTROL3:
1811     case S3C_SDHCI_CONTROL4:
1812         /* ignore */
1813         ret = 0;
1814         break;
1815     default:
1816         ret = sdhci_read(opaque, offset, size);
1817         break;
1818     }
1819 
1820     return ret;
1821 }
1822 
1823 static void sdhci_s3c_write(void *opaque, hwaddr offset, uint64_t val,
1824                             unsigned size)
1825 {
1826     switch (offset) {
1827     case S3C_SDHCI_CONTROL2:
1828     case S3C_SDHCI_CONTROL3:
1829     case S3C_SDHCI_CONTROL4:
1830         /* ignore */
1831         break;
1832     default:
1833         sdhci_write(opaque, offset, val, size);
1834         break;
1835     }
1836 }
1837 
1838 static const MemoryRegionOps sdhci_s3c_mmio_ops = {
1839     .read = sdhci_s3c_read,
1840     .write = sdhci_s3c_write,
1841     .valid = {
1842         .min_access_size = 1,
1843         .max_access_size = 4,
1844         .unaligned = false
1845     },
1846     .endianness = DEVICE_LITTLE_ENDIAN,
1847 };
1848 
1849 static void sdhci_s3c_init(Object *obj)
1850 {
1851     SDHCIState *s = SYSBUS_SDHCI(obj);
1852 
1853     s->io_ops = &sdhci_s3c_mmio_ops;
1854 }
1855 
1856 static const TypeInfo sdhci_s3c_info = {
1857     .name = TYPE_S3C_SDHCI  ,
1858     .parent = TYPE_SYSBUS_SDHCI,
1859     .instance_init = sdhci_s3c_init,
1860 };
1861 
1862 static void sdhci_register_types(void)
1863 {
1864     type_register_static(&sdhci_sysbus_info);
1865     type_register_static(&sdhci_bus_info);
1866     type_register_static(&imx_usdhc_info);
1867     type_register_static(&sdhci_s3c_info);
1868 }
1869 
1870 type_init(sdhci_register_types)
1871