xref: /qemu/hw/scsi/esp.c (revision f3ace75be8d472f6ffd40501147f08c9616faf1c)
1 /*
2  * QEMU ESP/NCR53C9x emulation
3  *
4  * Copyright (c) 2005-2006 Fabrice Bellard
5  * Copyright (c) 2012 Herve Poussineau
6  *
7  * Permission is hereby granted, free of charge, to any person obtaining a copy
8  * of this software and associated documentation files (the "Software"), to deal
9  * in the Software without restriction, including without limitation the rights
10  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
11  * copies of the Software, and to permit persons to whom the Software is
12  * furnished to do so, subject to the following conditions:
13  *
14  * The above copyright notice and this permission notice shall be included in
15  * all copies or substantial portions of the Software.
16  *
17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
18  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
20  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
21  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
22  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
23  * THE SOFTWARE.
24  */
25 
26 #include "qemu/osdep.h"
27 #include "hw/sysbus.h"
28 #include "migration/vmstate.h"
29 #include "hw/irq.h"
30 #include "hw/scsi/esp.h"
31 #include "trace.h"
32 #include "qemu/log.h"
33 #include "qemu/module.h"
34 
35 /*
36  * On Sparc32, this is the ESP (NCR53C90) part of chip STP2000 (Master I/O),
37  * also produced as NCR89C100. See
38  * http://www.ibiblio.org/pub/historic-linux/early-ports/Sparc/NCR/NCR89C100.txt
39  * and
40  * http://www.ibiblio.org/pub/historic-linux/early-ports/Sparc/NCR/NCR53C9X.txt
41  *
42  * On Macintosh Quadra it is a NCR53C96.
43  */
44 
45 static void esp_raise_irq(ESPState *s)
46 {
47     if (!(s->rregs[ESP_RSTAT] & STAT_INT)) {
48         s->rregs[ESP_RSTAT] |= STAT_INT;
49         qemu_irq_raise(s->irq);
50         trace_esp_raise_irq();
51     }
52 }
53 
54 static void esp_lower_irq(ESPState *s)
55 {
56     if (s->rregs[ESP_RSTAT] & STAT_INT) {
57         s->rregs[ESP_RSTAT] &= ~STAT_INT;
58         qemu_irq_lower(s->irq);
59         trace_esp_lower_irq();
60     }
61 }
62 
63 static void esp_raise_drq(ESPState *s)
64 {
65     qemu_irq_raise(s->irq_data);
66     trace_esp_raise_drq();
67 }
68 
69 static void esp_lower_drq(ESPState *s)
70 {
71     qemu_irq_lower(s->irq_data);
72     trace_esp_lower_drq();
73 }
74 
75 void esp_dma_enable(ESPState *s, int irq, int level)
76 {
77     if (level) {
78         s->dma_enabled = 1;
79         trace_esp_dma_enable();
80         if (s->dma_cb) {
81             s->dma_cb(s);
82             s->dma_cb = NULL;
83         }
84     } else {
85         trace_esp_dma_disable();
86         s->dma_enabled = 0;
87     }
88 }
89 
90 void esp_request_cancelled(SCSIRequest *req)
91 {
92     ESPState *s = req->hba_private;
93 
94     if (req == s->current_req) {
95         scsi_req_unref(s->current_req);
96         s->current_req = NULL;
97         s->current_dev = NULL;
98         s->async_len = 0;
99     }
100 }
101 
102 static void esp_fifo_push(Fifo8 *fifo, uint8_t val)
103 {
104     if (fifo8_num_used(fifo) == fifo->capacity) {
105         trace_esp_error_fifo_overrun();
106         return;
107     }
108 
109     fifo8_push(fifo, val);
110 }
111 
112 static uint8_t esp_fifo_pop(Fifo8 *fifo)
113 {
114     if (fifo8_is_empty(fifo)) {
115         return 0;
116     }
117 
118     return fifo8_pop(fifo);
119 }
120 
121 static uint32_t esp_fifo_pop_buf(Fifo8 *fifo, uint8_t *dest, int maxlen)
122 {
123     const uint8_t *buf;
124     uint32_t n;
125 
126     if (maxlen == 0) {
127         return 0;
128     }
129 
130     buf = fifo8_pop_buf(fifo, maxlen, &n);
131     if (dest) {
132         memcpy(dest, buf, n);
133     }
134 
135     return n;
136 }
137 
138 static uint32_t esp_get_tc(ESPState *s)
139 {
140     uint32_t dmalen;
141 
142     dmalen = s->rregs[ESP_TCLO];
143     dmalen |= s->rregs[ESP_TCMID] << 8;
144     dmalen |= s->rregs[ESP_TCHI] << 16;
145 
146     return dmalen;
147 }
148 
149 static void esp_set_tc(ESPState *s, uint32_t dmalen)
150 {
151     s->rregs[ESP_TCLO] = dmalen;
152     s->rregs[ESP_TCMID] = dmalen >> 8;
153     s->rregs[ESP_TCHI] = dmalen >> 16;
154 }
155 
156 static uint32_t esp_get_stc(ESPState *s)
157 {
158     uint32_t dmalen;
159 
160     dmalen = s->wregs[ESP_TCLO];
161     dmalen |= s->wregs[ESP_TCMID] << 8;
162     dmalen |= s->wregs[ESP_TCHI] << 16;
163 
164     return dmalen;
165 }
166 
167 static uint8_t esp_pdma_read(ESPState *s)
168 {
169     uint8_t val;
170 
171     if (s->do_cmd) {
172         val = esp_fifo_pop(&s->cmdfifo);
173     } else {
174         val = esp_fifo_pop(&s->fifo);
175     }
176 
177     return val;
178 }
179 
180 static void esp_pdma_write(ESPState *s, uint8_t val)
181 {
182     uint32_t dmalen = esp_get_tc(s);
183 
184     if (dmalen == 0) {
185         return;
186     }
187 
188     if (s->do_cmd) {
189         esp_fifo_push(&s->cmdfifo, val);
190     } else {
191         esp_fifo_push(&s->fifo, val);
192     }
193 
194     dmalen--;
195     esp_set_tc(s, dmalen);
196 }
197 
198 static void esp_set_pdma_cb(ESPState *s, enum pdma_cb cb)
199 {
200     s->pdma_cb = cb;
201 }
202 
203 static int esp_select(ESPState *s)
204 {
205     int target;
206 
207     target = s->wregs[ESP_WBUSID] & BUSID_DID;
208 
209     s->ti_size = 0;
210     fifo8_reset(&s->fifo);
211 
212     s->current_dev = scsi_device_find(&s->bus, 0, target, 0);
213     if (!s->current_dev) {
214         /* No such drive */
215         s->rregs[ESP_RSTAT] = 0;
216         s->rregs[ESP_RINTR] = INTR_DC;
217         s->rregs[ESP_RSEQ] = SEQ_0;
218         esp_raise_irq(s);
219         return -1;
220     }
221 
222     /*
223      * Note that we deliberately don't raise the IRQ here: this will be done
224      * either in do_command_phase() for DATA OUT transfers or by the deferred
225      * IRQ mechanism in esp_transfer_data() for DATA IN transfers
226      */
227     s->rregs[ESP_RINTR] |= INTR_FC;
228     s->rregs[ESP_RSEQ] = SEQ_CD;
229     return 0;
230 }
231 
232 static uint32_t get_cmd(ESPState *s, uint32_t maxlen)
233 {
234     uint8_t buf[ESP_CMDFIFO_SZ];
235     uint32_t dmalen, n;
236     int target;
237 
238     if (s->current_req) {
239         /* Started a new command before the old one finished.  Cancel it.  */
240         scsi_req_cancel(s->current_req);
241     }
242 
243     target = s->wregs[ESP_WBUSID] & BUSID_DID;
244     if (s->dma) {
245         dmalen = MIN(esp_get_tc(s), maxlen);
246         if (dmalen == 0) {
247             return 0;
248         }
249         if (s->dma_memory_read) {
250             s->dma_memory_read(s->dma_opaque, buf, dmalen);
251             dmalen = MIN(fifo8_num_free(&s->cmdfifo), dmalen);
252             fifo8_push_all(&s->cmdfifo, buf, dmalen);
253         } else {
254             if (esp_select(s) < 0) {
255                 return -1;
256             }
257             esp_raise_drq(s);
258             return 0;
259         }
260     } else {
261         dmalen = MIN(fifo8_num_used(&s->fifo), maxlen);
262         if (dmalen == 0) {
263             return 0;
264         }
265         n = esp_fifo_pop_buf(&s->fifo, buf, dmalen);
266         n = MIN(fifo8_num_free(&s->cmdfifo), n);
267         fifo8_push_all(&s->cmdfifo, buf, n);
268     }
269     trace_esp_get_cmd(dmalen, target);
270 
271     if (esp_select(s) < 0) {
272         return -1;
273     }
274     return dmalen;
275 }
276 
277 static void do_command_phase(ESPState *s)
278 {
279     uint32_t cmdlen;
280     int32_t datalen;
281     SCSIDevice *current_lun;
282     uint8_t buf[ESP_CMDFIFO_SZ];
283 
284     trace_esp_do_command_phase(s->lun);
285     cmdlen = fifo8_num_used(&s->cmdfifo);
286     if (!cmdlen || !s->current_dev) {
287         return;
288     }
289     esp_fifo_pop_buf(&s->cmdfifo, buf, cmdlen);
290 
291     current_lun = scsi_device_find(&s->bus, 0, s->current_dev->id, s->lun);
292     if (!current_lun) {
293         /* No such drive */
294         s->rregs[ESP_RSTAT] = 0;
295         s->rregs[ESP_RINTR] = INTR_DC;
296         s->rregs[ESP_RSEQ] = SEQ_0;
297         esp_raise_irq(s);
298         return;
299     }
300 
301     s->current_req = scsi_req_new(current_lun, 0, s->lun, buf, cmdlen, s);
302     datalen = scsi_req_enqueue(s->current_req);
303     s->ti_size = datalen;
304     fifo8_reset(&s->cmdfifo);
305     if (datalen != 0) {
306         s->rregs[ESP_RSTAT] = STAT_TC;
307         s->rregs[ESP_RSEQ] = SEQ_CD;
308         s->ti_cmd = 0;
309         esp_set_tc(s, 0);
310         if (datalen > 0) {
311             /*
312              * Switch to DATA IN phase but wait until initial data xfer is
313              * complete before raising the command completion interrupt
314              */
315             s->data_in_ready = false;
316             s->rregs[ESP_RSTAT] |= STAT_DI;
317         } else {
318             s->rregs[ESP_RSTAT] |= STAT_DO;
319             s->rregs[ESP_RINTR] |= INTR_BS | INTR_FC;
320             esp_raise_irq(s);
321             esp_lower_drq(s);
322         }
323         scsi_req_continue(s->current_req);
324         return;
325     }
326 }
327 
328 static void do_message_phase(ESPState *s)
329 {
330     if (s->cmdfifo_cdb_offset) {
331         uint8_t message = esp_fifo_pop(&s->cmdfifo);
332 
333         trace_esp_do_identify(message);
334         s->lun = message & 7;
335         s->cmdfifo_cdb_offset--;
336     }
337 
338     /* Ignore extended messages for now */
339     if (s->cmdfifo_cdb_offset) {
340         int len = MIN(s->cmdfifo_cdb_offset, fifo8_num_used(&s->cmdfifo));
341         esp_fifo_pop_buf(&s->cmdfifo, NULL, len);
342         s->cmdfifo_cdb_offset = 0;
343     }
344 }
345 
346 static void do_cmd(ESPState *s)
347 {
348     do_message_phase(s);
349     assert(s->cmdfifo_cdb_offset == 0);
350     do_command_phase(s);
351 }
352 
353 static void satn_pdma_cb(ESPState *s)
354 {
355     if (!esp_get_tc(s) && !fifo8_is_empty(&s->cmdfifo)) {
356         s->cmdfifo_cdb_offset = 1;
357         s->do_cmd = 0;
358         do_cmd(s);
359     }
360 }
361 
362 static void handle_satn(ESPState *s)
363 {
364     int32_t cmdlen;
365 
366     if (s->dma && !s->dma_enabled) {
367         s->dma_cb = handle_satn;
368         return;
369     }
370     esp_set_pdma_cb(s, SATN_PDMA_CB);
371     cmdlen = get_cmd(s, ESP_CMDFIFO_SZ);
372     if (cmdlen > 0) {
373         s->cmdfifo_cdb_offset = 1;
374         s->do_cmd = 0;
375         do_cmd(s);
376     } else if (cmdlen == 0) {
377         s->do_cmd = 1;
378         /* Target present, but no cmd yet - switch to command phase */
379         s->rregs[ESP_RSEQ] = SEQ_CD;
380         s->rregs[ESP_RSTAT] = STAT_CD;
381     }
382 }
383 
384 static void s_without_satn_pdma_cb(ESPState *s)
385 {
386     if (!esp_get_tc(s) && !fifo8_is_empty(&s->cmdfifo)) {
387         s->cmdfifo_cdb_offset = 0;
388         s->do_cmd = 0;
389         do_cmd(s);
390     }
391 }
392 
393 static void handle_s_without_atn(ESPState *s)
394 {
395     int32_t cmdlen;
396 
397     if (s->dma && !s->dma_enabled) {
398         s->dma_cb = handle_s_without_atn;
399         return;
400     }
401     esp_set_pdma_cb(s, S_WITHOUT_SATN_PDMA_CB);
402     cmdlen = get_cmd(s, ESP_CMDFIFO_SZ);
403     if (cmdlen > 0) {
404         s->cmdfifo_cdb_offset = 0;
405         s->do_cmd = 0;
406         do_cmd(s);
407     } else if (cmdlen == 0) {
408         s->do_cmd = 1;
409         /* Target present, but no cmd yet - switch to command phase */
410         s->rregs[ESP_RSEQ] = SEQ_CD;
411         s->rregs[ESP_RSTAT] = STAT_CD;
412     }
413 }
414 
415 static void satn_stop_pdma_cb(ESPState *s)
416 {
417     if (!esp_get_tc(s) && !fifo8_is_empty(&s->cmdfifo)) {
418         trace_esp_handle_satn_stop(fifo8_num_used(&s->cmdfifo));
419         s->do_cmd = 1;
420         s->cmdfifo_cdb_offset = 1;
421         s->rregs[ESP_RSTAT] = STAT_TC | STAT_CD;
422         s->rregs[ESP_RINTR] |= INTR_BS | INTR_FC;
423         s->rregs[ESP_RSEQ] = SEQ_CD;
424         esp_raise_irq(s);
425     }
426 }
427 
428 static void handle_satn_stop(ESPState *s)
429 {
430     int32_t cmdlen;
431 
432     if (s->dma && !s->dma_enabled) {
433         s->dma_cb = handle_satn_stop;
434         return;
435     }
436     esp_set_pdma_cb(s, SATN_STOP_PDMA_CB);
437     cmdlen = get_cmd(s, 1);
438     if (cmdlen > 0) {
439         trace_esp_handle_satn_stop(fifo8_num_used(&s->cmdfifo));
440         s->do_cmd = 1;
441         s->cmdfifo_cdb_offset = 1;
442         s->rregs[ESP_RSTAT] = STAT_MO;
443         s->rregs[ESP_RINTR] |= INTR_BS | INTR_FC;
444         s->rregs[ESP_RSEQ] = SEQ_MO;
445         esp_raise_irq(s);
446     } else if (cmdlen == 0) {
447         s->do_cmd = 1;
448         /* Target present, switch to message out phase */
449         s->rregs[ESP_RSEQ] = SEQ_MO;
450         s->rregs[ESP_RSTAT] = STAT_MO;
451     }
452 }
453 
454 static void write_response_pdma_cb(ESPState *s)
455 {
456     s->rregs[ESP_RSTAT] = STAT_TC | STAT_ST;
457     s->rregs[ESP_RINTR] |= INTR_BS | INTR_FC;
458     s->rregs[ESP_RSEQ] = SEQ_CD;
459     esp_raise_irq(s);
460 }
461 
462 static void write_response(ESPState *s)
463 {
464     uint8_t buf[2];
465 
466     trace_esp_write_response(s->status);
467 
468     buf[0] = s->status;
469     buf[1] = 0;
470 
471     if (s->dma) {
472         if (s->dma_memory_write) {
473             s->dma_memory_write(s->dma_opaque, buf, 2);
474             s->rregs[ESP_RSTAT] = STAT_TC | STAT_ST;
475             s->rregs[ESP_RINTR] |= INTR_BS | INTR_FC;
476             s->rregs[ESP_RSEQ] = SEQ_CD;
477         } else {
478             esp_set_pdma_cb(s, WRITE_RESPONSE_PDMA_CB);
479             esp_raise_drq(s);
480             return;
481         }
482     } else {
483         fifo8_reset(&s->fifo);
484         fifo8_push_all(&s->fifo, buf, 2);
485         s->rregs[ESP_RFLAGS] = 2;
486     }
487     esp_raise_irq(s);
488 }
489 
490 static void esp_dma_done(ESPState *s)
491 {
492     s->rregs[ESP_RSTAT] |= STAT_TC;
493     s->rregs[ESP_RINTR] |= INTR_BS;
494     s->rregs[ESP_RFLAGS] = 0;
495     esp_set_tc(s, 0);
496     esp_raise_irq(s);
497 }
498 
499 static void do_dma_pdma_cb(ESPState *s)
500 {
501     int to_device = ((s->rregs[ESP_RSTAT] & 7) == STAT_DO);
502     int len;
503     uint32_t n;
504 
505     if (s->do_cmd) {
506         /* Ensure we have received complete command after SATN and stop */
507         if (esp_get_tc(s) || fifo8_is_empty(&s->cmdfifo)) {
508             return;
509         }
510 
511         s->ti_size = 0;
512         if ((s->rregs[ESP_RSTAT] & 7) == STAT_CD) {
513             /* No command received */
514             if (s->cmdfifo_cdb_offset == fifo8_num_used(&s->cmdfifo)) {
515                 return;
516             }
517 
518             /* Command has been received */
519             s->do_cmd = 0;
520             do_cmd(s);
521         } else {
522             /*
523              * Extra message out bytes received: update cmdfifo_cdb_offset
524              * and then switch to command phase
525              */
526             s->cmdfifo_cdb_offset = fifo8_num_used(&s->cmdfifo);
527             s->rregs[ESP_RSTAT] = STAT_TC | STAT_CD;
528             s->rregs[ESP_RSEQ] = SEQ_CD;
529             s->rregs[ESP_RINTR] |= INTR_BS;
530             esp_raise_irq(s);
531         }
532         return;
533     }
534 
535     if (!s->current_req) {
536         return;
537     }
538 
539     if (to_device) {
540         /* Copy FIFO data to device */
541         len = MIN(s->async_len, ESP_FIFO_SZ);
542         len = MIN(len, fifo8_num_used(&s->fifo));
543         n = esp_fifo_pop_buf(&s->fifo, s->async_buf, len);
544         s->async_buf += n;
545         s->async_len -= n;
546         s->ti_size += n;
547 
548         if (n < len) {
549             /* Unaligned accesses can cause FIFO wraparound */
550             len = len - n;
551             n = esp_fifo_pop_buf(&s->fifo, s->async_buf, len);
552             s->async_buf += n;
553             s->async_len -= n;
554             s->ti_size += n;
555         }
556 
557         if (s->async_len == 0) {
558             scsi_req_continue(s->current_req);
559             return;
560         }
561 
562         if (esp_get_tc(s) == 0) {
563             esp_lower_drq(s);
564             esp_dma_done(s);
565         }
566 
567         return;
568     } else {
569         if (s->async_len == 0) {
570             /* Defer until the scsi layer has completed */
571             scsi_req_continue(s->current_req);
572             s->data_in_ready = false;
573             return;
574         }
575 
576         if (esp_get_tc(s) != 0) {
577             /* Copy device data to FIFO */
578             len = MIN(s->async_len, esp_get_tc(s));
579             len = MIN(len, fifo8_num_free(&s->fifo));
580             fifo8_push_all(&s->fifo, s->async_buf, len);
581             s->async_buf += len;
582             s->async_len -= len;
583             s->ti_size -= len;
584             esp_set_tc(s, esp_get_tc(s) - len);
585 
586             if (esp_get_tc(s) == 0) {
587                 /* Indicate transfer to FIFO is complete */
588                  s->rregs[ESP_RSTAT] |= STAT_TC;
589             }
590             return;
591         }
592 
593         /* Partially filled a scsi buffer. Complete immediately.  */
594         esp_lower_drq(s);
595         esp_dma_done(s);
596     }
597 }
598 
599 static void esp_do_dma(ESPState *s)
600 {
601     uint32_t len, cmdlen;
602     int to_device = ((s->rregs[ESP_RSTAT] & 7) == STAT_DO);
603     uint8_t buf[ESP_CMDFIFO_SZ];
604 
605     len = esp_get_tc(s);
606     if (s->do_cmd) {
607         /*
608          * handle_ti_cmd() case: esp_do_dma() is called only from
609          * handle_ti_cmd() with do_cmd != NULL (see the assert())
610          */
611         cmdlen = fifo8_num_used(&s->cmdfifo);
612         trace_esp_do_dma(cmdlen, len);
613         if (s->dma_memory_read) {
614             len = MIN(len, fifo8_num_free(&s->cmdfifo));
615             s->dma_memory_read(s->dma_opaque, buf, len);
616             fifo8_push_all(&s->cmdfifo, buf, len);
617         } else {
618             esp_set_pdma_cb(s, DO_DMA_PDMA_CB);
619             esp_raise_drq(s);
620             return;
621         }
622         trace_esp_handle_ti_cmd(cmdlen);
623         s->ti_size = 0;
624         if ((s->rregs[ESP_RSTAT] & 7) == STAT_CD) {
625             /* No command received */
626             if (s->cmdfifo_cdb_offset == fifo8_num_used(&s->cmdfifo)) {
627                 return;
628             }
629 
630             /* Command has been received */
631             s->do_cmd = 0;
632             do_cmd(s);
633         } else {
634             /*
635              * Extra message out bytes received: update cmdfifo_cdb_offset
636              * and then switch to command phase
637              */
638             s->cmdfifo_cdb_offset = fifo8_num_used(&s->cmdfifo);
639             s->rregs[ESP_RSTAT] = STAT_TC | STAT_CD;
640             s->rregs[ESP_RSEQ] = SEQ_CD;
641             s->rregs[ESP_RINTR] |= INTR_BS;
642             esp_raise_irq(s);
643         }
644         return;
645     }
646     if (!s->current_req) {
647         return;
648     }
649     if (s->async_len == 0) {
650         /* Defer until data is available.  */
651         return;
652     }
653     if (len > s->async_len) {
654         len = s->async_len;
655     }
656     if (to_device) {
657         if (s->dma_memory_read) {
658             s->dma_memory_read(s->dma_opaque, s->async_buf, len);
659         } else {
660             esp_set_pdma_cb(s, DO_DMA_PDMA_CB);
661             esp_raise_drq(s);
662             return;
663         }
664     } else {
665         if (s->dma_memory_write) {
666             s->dma_memory_write(s->dma_opaque, s->async_buf, len);
667         } else {
668             /* Adjust TC for any leftover data in the FIFO */
669             if (!fifo8_is_empty(&s->fifo)) {
670                 esp_set_tc(s, esp_get_tc(s) - fifo8_num_used(&s->fifo));
671             }
672 
673             /* Copy device data to FIFO */
674             len = MIN(len, fifo8_num_free(&s->fifo));
675             fifo8_push_all(&s->fifo, s->async_buf, len);
676             s->async_buf += len;
677             s->async_len -= len;
678             s->ti_size -= len;
679 
680             /*
681              * MacOS toolbox uses a TI length of 16 bytes for all commands, so
682              * commands shorter than this must be padded accordingly
683              */
684             if (len < esp_get_tc(s) && esp_get_tc(s) <= ESP_FIFO_SZ) {
685                 while (fifo8_num_used(&s->fifo) < ESP_FIFO_SZ) {
686                     esp_fifo_push(&s->fifo, 0);
687                     len++;
688                 }
689             }
690 
691             esp_set_tc(s, esp_get_tc(s) - len);
692             esp_set_pdma_cb(s, DO_DMA_PDMA_CB);
693             esp_raise_drq(s);
694 
695             /* Indicate transfer to FIFO is complete */
696             s->rregs[ESP_RSTAT] |= STAT_TC;
697             return;
698         }
699     }
700     esp_set_tc(s, esp_get_tc(s) - len);
701     s->async_buf += len;
702     s->async_len -= len;
703     if (to_device) {
704         s->ti_size += len;
705     } else {
706         s->ti_size -= len;
707     }
708     if (s->async_len == 0) {
709         scsi_req_continue(s->current_req);
710         /*
711          * If there is still data to be read from the device then
712          * complete the DMA operation immediately.  Otherwise defer
713          * until the scsi layer has completed.
714          */
715         if (to_device || esp_get_tc(s) != 0 || s->ti_size == 0) {
716             return;
717         }
718     }
719 
720     /* Partially filled a scsi buffer. Complete immediately.  */
721     esp_dma_done(s);
722     esp_lower_drq(s);
723 }
724 
725 static void esp_do_nodma(ESPState *s)
726 {
727     int to_device = ((s->rregs[ESP_RSTAT] & 7) == STAT_DO);
728     uint32_t cmdlen;
729     int len;
730 
731     if (s->do_cmd) {
732         cmdlen = fifo8_num_used(&s->cmdfifo);
733         trace_esp_handle_ti_cmd(cmdlen);
734         s->ti_size = 0;
735         if ((s->rregs[ESP_RSTAT] & 7) == STAT_CD) {
736             /* No command received */
737             if (s->cmdfifo_cdb_offset == fifo8_num_used(&s->cmdfifo)) {
738                 return;
739             }
740 
741             /* Command has been received */
742             s->do_cmd = 0;
743             do_cmd(s);
744         } else {
745             /*
746              * Extra message out bytes received: update cmdfifo_cdb_offset
747              * and then switch to command phase
748              */
749             s->cmdfifo_cdb_offset = fifo8_num_used(&s->cmdfifo);
750             s->rregs[ESP_RSTAT] = STAT_TC | STAT_CD;
751             s->rregs[ESP_RSEQ] = SEQ_CD;
752             s->rregs[ESP_RINTR] |= INTR_BS;
753             esp_raise_irq(s);
754         }
755         return;
756     }
757 
758     if (!s->current_req) {
759         return;
760     }
761 
762     if (s->async_len == 0) {
763         /* Defer until data is available.  */
764         return;
765     }
766 
767     if (to_device) {
768         len = MIN(s->async_len, ESP_FIFO_SZ);
769         len = MIN(len, fifo8_num_used(&s->fifo));
770         esp_fifo_pop_buf(&s->fifo, s->async_buf, len);
771         s->async_buf += len;
772         s->async_len -= len;
773         s->ti_size += len;
774     } else {
775         if (fifo8_is_empty(&s->fifo)) {
776             fifo8_push(&s->fifo, s->async_buf[0]);
777             s->async_buf++;
778             s->async_len--;
779             s->ti_size--;
780         }
781     }
782 
783     if (s->async_len == 0) {
784         scsi_req_continue(s->current_req);
785         return;
786     }
787 
788     s->rregs[ESP_RINTR] |= INTR_BS;
789     esp_raise_irq(s);
790 }
791 
792 static void esp_pdma_cb(ESPState *s)
793 {
794     switch (s->pdma_cb) {
795     case SATN_PDMA_CB:
796         satn_pdma_cb(s);
797         break;
798     case S_WITHOUT_SATN_PDMA_CB:
799         s_without_satn_pdma_cb(s);
800         break;
801     case SATN_STOP_PDMA_CB:
802         satn_stop_pdma_cb(s);
803         break;
804     case WRITE_RESPONSE_PDMA_CB:
805         write_response_pdma_cb(s);
806         break;
807     case DO_DMA_PDMA_CB:
808         do_dma_pdma_cb(s);
809         break;
810     default:
811         g_assert_not_reached();
812     }
813 }
814 
815 void esp_command_complete(SCSIRequest *req, size_t resid)
816 {
817     ESPState *s = req->hba_private;
818     int to_device = ((s->rregs[ESP_RSTAT] & 7) == STAT_DO);
819 
820     trace_esp_command_complete();
821 
822     /*
823      * Non-DMA transfers from the target will leave the last byte in
824      * the FIFO so don't reset ti_size in this case
825      */
826     if (s->dma || to_device) {
827         if (s->ti_size != 0) {
828             trace_esp_command_complete_unexpected();
829         }
830         s->ti_size = 0;
831     }
832 
833     s->async_len = 0;
834     if (req->status) {
835         trace_esp_command_complete_fail();
836     }
837     s->status = req->status;
838 
839     /*
840      * If the transfer is finished, switch to status phase. For non-DMA
841      * transfers from the target the last byte is still in the FIFO
842      */
843     if (s->ti_size == 0) {
844         s->rregs[ESP_RSTAT] = STAT_TC | STAT_ST;
845         esp_dma_done(s);
846         esp_lower_drq(s);
847     }
848 
849     if (s->current_req) {
850         scsi_req_unref(s->current_req);
851         s->current_req = NULL;
852         s->current_dev = NULL;
853     }
854 }
855 
856 void esp_transfer_data(SCSIRequest *req, uint32_t len)
857 {
858     ESPState *s = req->hba_private;
859     int to_device = ((s->rregs[ESP_RSTAT] & 7) == STAT_DO);
860     uint32_t dmalen = esp_get_tc(s);
861 
862     assert(!s->do_cmd);
863     trace_esp_transfer_data(dmalen, s->ti_size);
864     s->async_len = len;
865     s->async_buf = scsi_req_get_buf(req);
866 
867     if (!to_device && !s->data_in_ready) {
868         /*
869          * Initial incoming data xfer is complete so raise command
870          * completion interrupt
871          */
872         s->data_in_ready = true;
873         s->rregs[ESP_RSTAT] |= STAT_TC;
874         s->rregs[ESP_RINTR] |= INTR_BS;
875         esp_raise_irq(s);
876     }
877 
878     if (s->ti_cmd == 0) {
879         /*
880          * Always perform the initial transfer upon reception of the next TI
881          * command to ensure the DMA/non-DMA status of the command is correct.
882          * It is not possible to use s->dma directly in the section below as
883          * some OSs send non-DMA NOP commands after a DMA transfer. Hence if the
884          * async data transfer is delayed then s->dma is set incorrectly.
885          */
886         return;
887     }
888 
889     if (s->ti_cmd == (CMD_TI | CMD_DMA)) {
890         if (dmalen) {
891             esp_do_dma(s);
892         } else if (s->ti_size <= 0) {
893             /*
894              * If this was the last part of a DMA transfer then the
895              * completion interrupt is deferred to here.
896              */
897             esp_dma_done(s);
898             esp_lower_drq(s);
899         }
900     } else if (s->ti_cmd == CMD_TI) {
901         esp_do_nodma(s);
902     }
903 }
904 
905 static void handle_ti(ESPState *s)
906 {
907     uint32_t dmalen;
908 
909     if (s->dma && !s->dma_enabled) {
910         s->dma_cb = handle_ti;
911         return;
912     }
913 
914     s->ti_cmd = s->rregs[ESP_CMD];
915     if (s->dma) {
916         dmalen = esp_get_tc(s);
917         trace_esp_handle_ti(dmalen);
918         s->rregs[ESP_RSTAT] &= ~STAT_TC;
919         esp_do_dma(s);
920     } else {
921         trace_esp_handle_ti(s->ti_size);
922         esp_do_nodma(s);
923     }
924 }
925 
926 void esp_hard_reset(ESPState *s)
927 {
928     memset(s->rregs, 0, ESP_REGS);
929     memset(s->wregs, 0, ESP_REGS);
930     s->tchi_written = 0;
931     s->ti_size = 0;
932     s->async_len = 0;
933     fifo8_reset(&s->fifo);
934     fifo8_reset(&s->cmdfifo);
935     s->dma = 0;
936     s->do_cmd = 0;
937     s->dma_cb = NULL;
938 
939     s->rregs[ESP_CFG1] = 7;
940 }
941 
942 static void esp_soft_reset(ESPState *s)
943 {
944     qemu_irq_lower(s->irq);
945     qemu_irq_lower(s->irq_data);
946     esp_hard_reset(s);
947 }
948 
949 static void esp_bus_reset(ESPState *s)
950 {
951     bus_cold_reset(BUS(&s->bus));
952 }
953 
954 static void parent_esp_reset(ESPState *s, int irq, int level)
955 {
956     if (level) {
957         esp_soft_reset(s);
958     }
959 }
960 
961 uint64_t esp_reg_read(ESPState *s, uint32_t saddr)
962 {
963     uint32_t val;
964 
965     switch (saddr) {
966     case ESP_FIFO:
967         if (s->dma_memory_read && s->dma_memory_write &&
968                 (s->rregs[ESP_RSTAT] & STAT_PIO_MASK) == 0) {
969             /* Data out.  */
970             qemu_log_mask(LOG_UNIMP, "esp: PIO data read not implemented\n");
971             s->rregs[ESP_FIFO] = 0;
972         } else {
973             if ((s->rregs[ESP_RSTAT] & 0x7) == STAT_DI) {
974                 if (s->ti_size) {
975                     esp_do_nodma(s);
976                 } else {
977                     /*
978                      * The last byte of a non-DMA transfer has been read out
979                      * of the FIFO so switch to status phase
980                      */
981                     s->rregs[ESP_RSTAT] = STAT_TC | STAT_ST;
982                 }
983             }
984             s->rregs[ESP_FIFO] = esp_fifo_pop(&s->fifo);
985         }
986         val = s->rregs[ESP_FIFO];
987         break;
988     case ESP_RINTR:
989         /*
990          * Clear sequence step, interrupt register and all status bits
991          * except TC
992          */
993         val = s->rregs[ESP_RINTR];
994         s->rregs[ESP_RINTR] = 0;
995         s->rregs[ESP_RSTAT] &= ~STAT_TC;
996         /*
997          * According to the datasheet ESP_RSEQ should be cleared, but as the
998          * emulation currently defers information transfers to the next TI
999          * command leave it for now so that pedantic guests such as the old
1000          * Linux 2.6 driver see the correct flags before the next SCSI phase
1001          * transition.
1002          *
1003          * s->rregs[ESP_RSEQ] = SEQ_0;
1004          */
1005         esp_lower_irq(s);
1006         break;
1007     case ESP_TCHI:
1008         /* Return the unique id if the value has never been written */
1009         if (!s->tchi_written) {
1010             val = s->chip_id;
1011         } else {
1012             val = s->rregs[saddr];
1013         }
1014         break;
1015      case ESP_RFLAGS:
1016         /* Bottom 5 bits indicate number of bytes in FIFO */
1017         val = fifo8_num_used(&s->fifo);
1018         break;
1019     default:
1020         val = s->rregs[saddr];
1021         break;
1022     }
1023 
1024     trace_esp_mem_readb(saddr, val);
1025     return val;
1026 }
1027 
1028 void esp_reg_write(ESPState *s, uint32_t saddr, uint64_t val)
1029 {
1030     trace_esp_mem_writeb(saddr, s->wregs[saddr], val);
1031     switch (saddr) {
1032     case ESP_TCHI:
1033         s->tchi_written = true;
1034         /* fall through */
1035     case ESP_TCLO:
1036     case ESP_TCMID:
1037         s->rregs[ESP_RSTAT] &= ~STAT_TC;
1038         break;
1039     case ESP_FIFO:
1040         if (s->do_cmd) {
1041             esp_fifo_push(&s->cmdfifo, val);
1042 
1043             /*
1044              * If any unexpected message out/command phase data is
1045              * transferred using non-DMA, raise the interrupt
1046              */
1047             if (s->rregs[ESP_CMD] == CMD_TI) {
1048                 s->rregs[ESP_RINTR] |= INTR_BS;
1049                 esp_raise_irq(s);
1050             }
1051         } else {
1052             esp_fifo_push(&s->fifo, val);
1053         }
1054         break;
1055     case ESP_CMD:
1056         s->rregs[saddr] = val;
1057         if (val & CMD_DMA) {
1058             s->dma = 1;
1059             /* Reload DMA counter.  */
1060             if (esp_get_stc(s) == 0) {
1061                 esp_set_tc(s, 0x10000);
1062             } else {
1063                 esp_set_tc(s, esp_get_stc(s));
1064             }
1065         } else {
1066             s->dma = 0;
1067         }
1068         switch (val & CMD_CMD) {
1069         case CMD_NOP:
1070             trace_esp_mem_writeb_cmd_nop(val);
1071             break;
1072         case CMD_FLUSH:
1073             trace_esp_mem_writeb_cmd_flush(val);
1074             fifo8_reset(&s->fifo);
1075             break;
1076         case CMD_RESET:
1077             trace_esp_mem_writeb_cmd_reset(val);
1078             esp_soft_reset(s);
1079             break;
1080         case CMD_BUSRESET:
1081             trace_esp_mem_writeb_cmd_bus_reset(val);
1082             esp_bus_reset(s);
1083             if (!(s->wregs[ESP_CFG1] & CFG1_RESREPT)) {
1084                 s->rregs[ESP_RINTR] |= INTR_RST;
1085                 esp_raise_irq(s);
1086             }
1087             break;
1088         case CMD_TI:
1089             trace_esp_mem_writeb_cmd_ti(val);
1090             handle_ti(s);
1091             break;
1092         case CMD_ICCS:
1093             trace_esp_mem_writeb_cmd_iccs(val);
1094             write_response(s);
1095             s->rregs[ESP_RINTR] |= INTR_FC;
1096             s->rregs[ESP_RSTAT] |= STAT_MI;
1097             break;
1098         case CMD_MSGACC:
1099             trace_esp_mem_writeb_cmd_msgacc(val);
1100             s->rregs[ESP_RINTR] |= INTR_DC;
1101             s->rregs[ESP_RSEQ] = 0;
1102             s->rregs[ESP_RFLAGS] = 0;
1103             esp_raise_irq(s);
1104             break;
1105         case CMD_PAD:
1106             trace_esp_mem_writeb_cmd_pad(val);
1107             s->rregs[ESP_RSTAT] = STAT_TC;
1108             s->rregs[ESP_RINTR] |= INTR_FC;
1109             s->rregs[ESP_RSEQ] = 0;
1110             break;
1111         case CMD_SATN:
1112             trace_esp_mem_writeb_cmd_satn(val);
1113             break;
1114         case CMD_RSTATN:
1115             trace_esp_mem_writeb_cmd_rstatn(val);
1116             break;
1117         case CMD_SEL:
1118             trace_esp_mem_writeb_cmd_sel(val);
1119             handle_s_without_atn(s);
1120             break;
1121         case CMD_SELATN:
1122             trace_esp_mem_writeb_cmd_selatn(val);
1123             handle_satn(s);
1124             break;
1125         case CMD_SELATNS:
1126             trace_esp_mem_writeb_cmd_selatns(val);
1127             handle_satn_stop(s);
1128             break;
1129         case CMD_ENSEL:
1130             trace_esp_mem_writeb_cmd_ensel(val);
1131             s->rregs[ESP_RINTR] = 0;
1132             break;
1133         case CMD_DISSEL:
1134             trace_esp_mem_writeb_cmd_dissel(val);
1135             s->rregs[ESP_RINTR] = 0;
1136             esp_raise_irq(s);
1137             break;
1138         default:
1139             trace_esp_error_unhandled_command(val);
1140             break;
1141         }
1142         break;
1143     case ESP_WBUSID ... ESP_WSYNO:
1144         break;
1145     case ESP_CFG1:
1146     case ESP_CFG2: case ESP_CFG3:
1147     case ESP_RES3: case ESP_RES4:
1148         s->rregs[saddr] = val;
1149         break;
1150     case ESP_WCCF ... ESP_WTEST:
1151         break;
1152     default:
1153         trace_esp_error_invalid_write(val, saddr);
1154         return;
1155     }
1156     s->wregs[saddr] = val;
1157 }
1158 
1159 static bool esp_mem_accepts(void *opaque, hwaddr addr,
1160                             unsigned size, bool is_write,
1161                             MemTxAttrs attrs)
1162 {
1163     return (size == 1) || (is_write && size == 4);
1164 }
1165 
1166 static bool esp_is_before_version_5(void *opaque, int version_id)
1167 {
1168     ESPState *s = ESP(opaque);
1169 
1170     version_id = MIN(version_id, s->mig_version_id);
1171     return version_id < 5;
1172 }
1173 
1174 static bool esp_is_version_5(void *opaque, int version_id)
1175 {
1176     ESPState *s = ESP(opaque);
1177 
1178     version_id = MIN(version_id, s->mig_version_id);
1179     return version_id >= 5;
1180 }
1181 
1182 static bool esp_is_version_6(void *opaque, int version_id)
1183 {
1184     ESPState *s = ESP(opaque);
1185 
1186     version_id = MIN(version_id, s->mig_version_id);
1187     return version_id >= 6;
1188 }
1189 
1190 int esp_pre_save(void *opaque)
1191 {
1192     ESPState *s = ESP(object_resolve_path_component(
1193                       OBJECT(opaque), "esp"));
1194 
1195     s->mig_version_id = vmstate_esp.version_id;
1196     return 0;
1197 }
1198 
1199 static int esp_post_load(void *opaque, int version_id)
1200 {
1201     ESPState *s = ESP(opaque);
1202     int len, i;
1203 
1204     version_id = MIN(version_id, s->mig_version_id);
1205 
1206     if (version_id < 5) {
1207         esp_set_tc(s, s->mig_dma_left);
1208 
1209         /* Migrate ti_buf to fifo */
1210         len = s->mig_ti_wptr - s->mig_ti_rptr;
1211         for (i = 0; i < len; i++) {
1212             fifo8_push(&s->fifo, s->mig_ti_buf[i]);
1213         }
1214 
1215         /* Migrate cmdbuf to cmdfifo */
1216         for (i = 0; i < s->mig_cmdlen; i++) {
1217             fifo8_push(&s->cmdfifo, s->mig_cmdbuf[i]);
1218         }
1219     }
1220 
1221     s->mig_version_id = vmstate_esp.version_id;
1222     return 0;
1223 }
1224 
1225 /*
1226  * PDMA (or pseudo-DMA) is only used on the Macintosh and requires the
1227  * guest CPU to perform the transfers between the SCSI bus and memory
1228  * itself. This is indicated by the dma_memory_read and dma_memory_write
1229  * functions being NULL (in contrast to the ESP PCI device) whilst
1230  * dma_enabled is still set.
1231  */
1232 
1233 static bool esp_pdma_needed(void *opaque)
1234 {
1235     ESPState *s = ESP(opaque);
1236 
1237     return s->dma_memory_read == NULL && s->dma_memory_write == NULL &&
1238            s->dma_enabled;
1239 }
1240 
1241 static const VMStateDescription vmstate_esp_pdma = {
1242     .name = "esp/pdma",
1243     .version_id = 0,
1244     .minimum_version_id = 0,
1245     .needed = esp_pdma_needed,
1246     .fields = (const VMStateField[]) {
1247         VMSTATE_UINT8(pdma_cb, ESPState),
1248         VMSTATE_END_OF_LIST()
1249     }
1250 };
1251 
1252 const VMStateDescription vmstate_esp = {
1253     .name = "esp",
1254     .version_id = 6,
1255     .minimum_version_id = 3,
1256     .post_load = esp_post_load,
1257     .fields = (const VMStateField[]) {
1258         VMSTATE_BUFFER(rregs, ESPState),
1259         VMSTATE_BUFFER(wregs, ESPState),
1260         VMSTATE_INT32(ti_size, ESPState),
1261         VMSTATE_UINT32_TEST(mig_ti_rptr, ESPState, esp_is_before_version_5),
1262         VMSTATE_UINT32_TEST(mig_ti_wptr, ESPState, esp_is_before_version_5),
1263         VMSTATE_BUFFER_TEST(mig_ti_buf, ESPState, esp_is_before_version_5),
1264         VMSTATE_UINT32(status, ESPState),
1265         VMSTATE_UINT32_TEST(mig_deferred_status, ESPState,
1266                             esp_is_before_version_5),
1267         VMSTATE_BOOL_TEST(mig_deferred_complete, ESPState,
1268                           esp_is_before_version_5),
1269         VMSTATE_UINT32(dma, ESPState),
1270         VMSTATE_STATIC_BUFFER(mig_cmdbuf, ESPState, 0,
1271                               esp_is_before_version_5, 0, 16),
1272         VMSTATE_STATIC_BUFFER(mig_cmdbuf, ESPState, 4,
1273                               esp_is_before_version_5, 16,
1274                               sizeof(typeof_field(ESPState, mig_cmdbuf))),
1275         VMSTATE_UINT32_TEST(mig_cmdlen, ESPState, esp_is_before_version_5),
1276         VMSTATE_UINT32(do_cmd, ESPState),
1277         VMSTATE_UINT32_TEST(mig_dma_left, ESPState, esp_is_before_version_5),
1278         VMSTATE_BOOL_TEST(data_in_ready, ESPState, esp_is_version_5),
1279         VMSTATE_UINT8_TEST(cmdfifo_cdb_offset, ESPState, esp_is_version_5),
1280         VMSTATE_FIFO8_TEST(fifo, ESPState, esp_is_version_5),
1281         VMSTATE_FIFO8_TEST(cmdfifo, ESPState, esp_is_version_5),
1282         VMSTATE_UINT8_TEST(ti_cmd, ESPState, esp_is_version_5),
1283         VMSTATE_UINT8_TEST(lun, ESPState, esp_is_version_6),
1284         VMSTATE_END_OF_LIST()
1285     },
1286     .subsections = (const VMStateDescription * const []) {
1287         &vmstate_esp_pdma,
1288         NULL
1289     }
1290 };
1291 
1292 static void sysbus_esp_mem_write(void *opaque, hwaddr addr,
1293                                  uint64_t val, unsigned int size)
1294 {
1295     SysBusESPState *sysbus = opaque;
1296     ESPState *s = ESP(&sysbus->esp);
1297     uint32_t saddr;
1298 
1299     saddr = addr >> sysbus->it_shift;
1300     esp_reg_write(s, saddr, val);
1301 }
1302 
1303 static uint64_t sysbus_esp_mem_read(void *opaque, hwaddr addr,
1304                                     unsigned int size)
1305 {
1306     SysBusESPState *sysbus = opaque;
1307     ESPState *s = ESP(&sysbus->esp);
1308     uint32_t saddr;
1309 
1310     saddr = addr >> sysbus->it_shift;
1311     return esp_reg_read(s, saddr);
1312 }
1313 
1314 static const MemoryRegionOps sysbus_esp_mem_ops = {
1315     .read = sysbus_esp_mem_read,
1316     .write = sysbus_esp_mem_write,
1317     .endianness = DEVICE_NATIVE_ENDIAN,
1318     .valid.accepts = esp_mem_accepts,
1319 };
1320 
1321 static void sysbus_esp_pdma_write(void *opaque, hwaddr addr,
1322                                   uint64_t val, unsigned int size)
1323 {
1324     SysBusESPState *sysbus = opaque;
1325     ESPState *s = ESP(&sysbus->esp);
1326 
1327     trace_esp_pdma_write(size);
1328 
1329     switch (size) {
1330     case 1:
1331         esp_pdma_write(s, val);
1332         break;
1333     case 2:
1334         esp_pdma_write(s, val >> 8);
1335         esp_pdma_write(s, val);
1336         break;
1337     }
1338     esp_pdma_cb(s);
1339 }
1340 
1341 static uint64_t sysbus_esp_pdma_read(void *opaque, hwaddr addr,
1342                                      unsigned int size)
1343 {
1344     SysBusESPState *sysbus = opaque;
1345     ESPState *s = ESP(&sysbus->esp);
1346     uint64_t val = 0;
1347 
1348     trace_esp_pdma_read(size);
1349 
1350     switch (size) {
1351     case 1:
1352         val = esp_pdma_read(s);
1353         break;
1354     case 2:
1355         val = esp_pdma_read(s);
1356         val = (val << 8) | esp_pdma_read(s);
1357         break;
1358     }
1359     if (fifo8_num_used(&s->fifo) < 2) {
1360         esp_pdma_cb(s);
1361     }
1362     return val;
1363 }
1364 
1365 static void *esp_load_request(QEMUFile *f, SCSIRequest *req)
1366 {
1367     ESPState *s = container_of(req->bus, ESPState, bus);
1368 
1369     scsi_req_ref(req);
1370     s->current_req = req;
1371     return s;
1372 }
1373 
1374 static const MemoryRegionOps sysbus_esp_pdma_ops = {
1375     .read = sysbus_esp_pdma_read,
1376     .write = sysbus_esp_pdma_write,
1377     .endianness = DEVICE_NATIVE_ENDIAN,
1378     .valid.min_access_size = 1,
1379     .valid.max_access_size = 4,
1380     .impl.min_access_size = 1,
1381     .impl.max_access_size = 2,
1382 };
1383 
1384 static const struct SCSIBusInfo esp_scsi_info = {
1385     .tcq = false,
1386     .max_target = ESP_MAX_DEVS,
1387     .max_lun = 7,
1388 
1389     .load_request = esp_load_request,
1390     .transfer_data = esp_transfer_data,
1391     .complete = esp_command_complete,
1392     .cancel = esp_request_cancelled
1393 };
1394 
1395 static void sysbus_esp_gpio_demux(void *opaque, int irq, int level)
1396 {
1397     SysBusESPState *sysbus = SYSBUS_ESP(opaque);
1398     ESPState *s = ESP(&sysbus->esp);
1399 
1400     switch (irq) {
1401     case 0:
1402         parent_esp_reset(s, irq, level);
1403         break;
1404     case 1:
1405         esp_dma_enable(s, irq, level);
1406         break;
1407     }
1408 }
1409 
1410 static void sysbus_esp_realize(DeviceState *dev, Error **errp)
1411 {
1412     SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
1413     SysBusESPState *sysbus = SYSBUS_ESP(dev);
1414     ESPState *s = ESP(&sysbus->esp);
1415 
1416     if (!qdev_realize(DEVICE(s), NULL, errp)) {
1417         return;
1418     }
1419 
1420     sysbus_init_irq(sbd, &s->irq);
1421     sysbus_init_irq(sbd, &s->irq_data);
1422     assert(sysbus->it_shift != -1);
1423 
1424     s->chip_id = TCHI_FAS100A;
1425     memory_region_init_io(&sysbus->iomem, OBJECT(sysbus), &sysbus_esp_mem_ops,
1426                           sysbus, "esp-regs", ESP_REGS << sysbus->it_shift);
1427     sysbus_init_mmio(sbd, &sysbus->iomem);
1428     memory_region_init_io(&sysbus->pdma, OBJECT(sysbus), &sysbus_esp_pdma_ops,
1429                           sysbus, "esp-pdma", 4);
1430     sysbus_init_mmio(sbd, &sysbus->pdma);
1431 
1432     qdev_init_gpio_in(dev, sysbus_esp_gpio_demux, 2);
1433 
1434     scsi_bus_init(&s->bus, sizeof(s->bus), dev, &esp_scsi_info);
1435 }
1436 
1437 static void sysbus_esp_hard_reset(DeviceState *dev)
1438 {
1439     SysBusESPState *sysbus = SYSBUS_ESP(dev);
1440     ESPState *s = ESP(&sysbus->esp);
1441 
1442     esp_hard_reset(s);
1443 }
1444 
1445 static void sysbus_esp_init(Object *obj)
1446 {
1447     SysBusESPState *sysbus = SYSBUS_ESP(obj);
1448 
1449     object_initialize_child(obj, "esp", &sysbus->esp, TYPE_ESP);
1450 }
1451 
1452 static const VMStateDescription vmstate_sysbus_esp_scsi = {
1453     .name = "sysbusespscsi",
1454     .version_id = 2,
1455     .minimum_version_id = 1,
1456     .pre_save = esp_pre_save,
1457     .fields = (const VMStateField[]) {
1458         VMSTATE_UINT8_V(esp.mig_version_id, SysBusESPState, 2),
1459         VMSTATE_STRUCT(esp, SysBusESPState, 0, vmstate_esp, ESPState),
1460         VMSTATE_END_OF_LIST()
1461     }
1462 };
1463 
1464 static void sysbus_esp_class_init(ObjectClass *klass, void *data)
1465 {
1466     DeviceClass *dc = DEVICE_CLASS(klass);
1467 
1468     dc->realize = sysbus_esp_realize;
1469     dc->reset = sysbus_esp_hard_reset;
1470     dc->vmsd = &vmstate_sysbus_esp_scsi;
1471     set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
1472 }
1473 
1474 static const TypeInfo sysbus_esp_info = {
1475     .name          = TYPE_SYSBUS_ESP,
1476     .parent        = TYPE_SYS_BUS_DEVICE,
1477     .instance_init = sysbus_esp_init,
1478     .instance_size = sizeof(SysBusESPState),
1479     .class_init    = sysbus_esp_class_init,
1480 };
1481 
1482 static void esp_finalize(Object *obj)
1483 {
1484     ESPState *s = ESP(obj);
1485 
1486     fifo8_destroy(&s->fifo);
1487     fifo8_destroy(&s->cmdfifo);
1488 }
1489 
1490 static void esp_init(Object *obj)
1491 {
1492     ESPState *s = ESP(obj);
1493 
1494     fifo8_create(&s->fifo, ESP_FIFO_SZ);
1495     fifo8_create(&s->cmdfifo, ESP_CMDFIFO_SZ);
1496 }
1497 
1498 static void esp_class_init(ObjectClass *klass, void *data)
1499 {
1500     DeviceClass *dc = DEVICE_CLASS(klass);
1501 
1502     /* internal device for sysbusesp/pciespscsi, not user-creatable */
1503     dc->user_creatable = false;
1504     set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
1505 }
1506 
1507 static const TypeInfo esp_info = {
1508     .name = TYPE_ESP,
1509     .parent = TYPE_DEVICE,
1510     .instance_init = esp_init,
1511     .instance_finalize = esp_finalize,
1512     .instance_size = sizeof(ESPState),
1513     .class_init = esp_class_init,
1514 };
1515 
1516 static void esp_register_types(void)
1517 {
1518     type_register_static(&sysbus_esp_info);
1519     type_register_static(&esp_info);
1520 }
1521 
1522 type_init(esp_register_types)
1523