xref: /qemu/hw/scsi/esp.c (revision abc139cda0817ed4682b6d3eabef65094eb82600)
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, n2;
125     int len;
126 
127     if (maxlen == 0) {
128         return 0;
129     }
130 
131     len = maxlen;
132     buf = fifo8_pop_buf(fifo, len, &n);
133     if (dest) {
134         memcpy(dest, buf, n);
135     }
136 
137     /* Add FIFO wraparound if needed */
138     len -= n;
139     len = MIN(len, fifo8_num_used(fifo));
140     if (len) {
141         buf = fifo8_pop_buf(fifo, len, &n2);
142         if (dest) {
143             memcpy(&dest[n], buf, n2);
144         }
145         n += n2;
146     }
147 
148     return n;
149 }
150 
151 static uint32_t esp_get_tc(ESPState *s)
152 {
153     uint32_t dmalen;
154 
155     dmalen = s->rregs[ESP_TCLO];
156     dmalen |= s->rregs[ESP_TCMID] << 8;
157     dmalen |= s->rregs[ESP_TCHI] << 16;
158 
159     return dmalen;
160 }
161 
162 static void esp_set_tc(ESPState *s, uint32_t dmalen)
163 {
164     uint32_t old_tc = esp_get_tc(s);
165 
166     s->rregs[ESP_TCLO] = dmalen;
167     s->rregs[ESP_TCMID] = dmalen >> 8;
168     s->rregs[ESP_TCHI] = dmalen >> 16;
169 
170     if (old_tc && dmalen == 0) {
171         s->rregs[ESP_RSTAT] |= STAT_TC;
172     }
173 }
174 
175 static uint32_t esp_get_stc(ESPState *s)
176 {
177     uint32_t dmalen;
178 
179     dmalen = s->wregs[ESP_TCLO];
180     dmalen |= s->wregs[ESP_TCMID] << 8;
181     dmalen |= s->wregs[ESP_TCHI] << 16;
182 
183     return dmalen;
184 }
185 
186 static const char *esp_phase_names[8] = {
187     "DATA OUT", "DATA IN", "COMMAND", "STATUS",
188     "(reserved)", "(reserved)", "MESSAGE OUT", "MESSAGE IN"
189 };
190 
191 static void esp_set_phase(ESPState *s, uint8_t phase)
192 {
193     s->rregs[ESP_RSTAT] &= ~7;
194     s->rregs[ESP_RSTAT] |= phase;
195 
196     trace_esp_set_phase(esp_phase_names[phase]);
197 }
198 
199 static uint8_t esp_pdma_read(ESPState *s)
200 {
201     uint8_t val;
202 
203     val = esp_fifo_pop(&s->fifo);
204     return val;
205 }
206 
207 static void esp_pdma_write(ESPState *s, uint8_t val)
208 {
209     uint32_t dmalen = esp_get_tc(s);
210 
211     if (dmalen == 0) {
212         return;
213     }
214 
215     esp_fifo_push(&s->fifo, val);
216 
217     dmalen--;
218     esp_set_tc(s, dmalen);
219 }
220 
221 static void esp_set_pdma_cb(ESPState *s, enum pdma_cb cb)
222 {
223     s->pdma_cb = cb;
224 }
225 
226 static int esp_select(ESPState *s)
227 {
228     int target;
229 
230     target = s->wregs[ESP_WBUSID] & BUSID_DID;
231 
232     s->ti_size = 0;
233 
234     if (s->current_req) {
235         /* Started a new command before the old one finished. Cancel it. */
236         scsi_req_cancel(s->current_req);
237     }
238 
239     s->current_dev = scsi_device_find(&s->bus, 0, target, 0);
240     if (!s->current_dev) {
241         /* No such drive */
242         s->rregs[ESP_RSTAT] = 0;
243         s->rregs[ESP_RINTR] = INTR_DC;
244         s->rregs[ESP_RSEQ] = SEQ_0;
245         esp_raise_irq(s);
246         return -1;
247     }
248 
249     /*
250      * Note that we deliberately don't raise the IRQ here: this will be done
251      * either in do_command_phase() for DATA OUT transfers or by the deferred
252      * IRQ mechanism in esp_transfer_data() for DATA IN transfers
253      */
254     s->rregs[ESP_RINTR] |= INTR_FC;
255     s->rregs[ESP_RSEQ] = SEQ_CD;
256     return 0;
257 }
258 
259 static uint32_t get_cmd(ESPState *s, uint32_t maxlen)
260 {
261     uint8_t buf[ESP_CMDFIFO_SZ];
262     uint32_t dmalen, n;
263     int target;
264 
265     target = s->wregs[ESP_WBUSID] & BUSID_DID;
266     if (s->dma) {
267         dmalen = MIN(esp_get_tc(s), maxlen);
268         if (dmalen == 0) {
269             return 0;
270         }
271         if (s->dma_memory_read) {
272             s->dma_memory_read(s->dma_opaque, buf, dmalen);
273             dmalen = MIN(fifo8_num_free(&s->cmdfifo), dmalen);
274             fifo8_push_all(&s->cmdfifo, buf, dmalen);
275             esp_set_tc(s, esp_get_tc(s) - dmalen);
276         } else {
277             return 0;
278         }
279     } else {
280         dmalen = MIN(fifo8_num_used(&s->fifo), maxlen);
281         if (dmalen == 0) {
282             return 0;
283         }
284         n = esp_fifo_pop_buf(&s->fifo, buf, dmalen);
285         n = MIN(fifo8_num_free(&s->cmdfifo), n);
286         fifo8_push_all(&s->cmdfifo, buf, n);
287     }
288     trace_esp_get_cmd(dmalen, target);
289 
290     return dmalen;
291 }
292 
293 static void do_command_phase(ESPState *s)
294 {
295     uint32_t cmdlen;
296     int32_t datalen;
297     SCSIDevice *current_lun;
298     uint8_t buf[ESP_CMDFIFO_SZ];
299 
300     trace_esp_do_command_phase(s->lun);
301     cmdlen = fifo8_num_used(&s->cmdfifo);
302     if (!cmdlen || !s->current_dev) {
303         return;
304     }
305     esp_fifo_pop_buf(&s->cmdfifo, buf, cmdlen);
306 
307     current_lun = scsi_device_find(&s->bus, 0, s->current_dev->id, s->lun);
308     if (!current_lun) {
309         /* No such drive */
310         s->rregs[ESP_RSTAT] = 0;
311         s->rregs[ESP_RINTR] = INTR_DC;
312         s->rregs[ESP_RSEQ] = SEQ_0;
313         esp_raise_irq(s);
314         return;
315     }
316 
317     s->current_req = scsi_req_new(current_lun, 0, s->lun, buf, cmdlen, s);
318     datalen = scsi_req_enqueue(s->current_req);
319     s->ti_size = datalen;
320     fifo8_reset(&s->cmdfifo);
321     if (datalen != 0) {
322         s->rregs[ESP_RSTAT] = STAT_TC;
323         s->rregs[ESP_RSEQ] = SEQ_CD;
324         s->ti_cmd = 0;
325         esp_set_tc(s, 0);
326         if (datalen > 0) {
327             /*
328              * Switch to DATA IN phase but wait until initial data xfer is
329              * complete before raising the command completion interrupt
330              */
331             s->data_in_ready = false;
332             esp_set_phase(s, STAT_DI);
333         } else {
334             esp_set_phase(s, STAT_DO);
335             s->rregs[ESP_RINTR] |= INTR_BS | INTR_FC;
336             esp_raise_irq(s);
337             esp_lower_drq(s);
338         }
339         scsi_req_continue(s->current_req);
340         return;
341     }
342 }
343 
344 static void do_message_phase(ESPState *s)
345 {
346     if (s->cmdfifo_cdb_offset) {
347         uint8_t message = esp_fifo_pop(&s->cmdfifo);
348 
349         trace_esp_do_identify(message);
350         s->lun = message & 7;
351         s->cmdfifo_cdb_offset--;
352     }
353 
354     /* Ignore extended messages for now */
355     if (s->cmdfifo_cdb_offset) {
356         int len = MIN(s->cmdfifo_cdb_offset, fifo8_num_used(&s->cmdfifo));
357         esp_fifo_pop_buf(&s->cmdfifo, NULL, len);
358         s->cmdfifo_cdb_offset = 0;
359     }
360 }
361 
362 static void do_cmd(ESPState *s)
363 {
364     do_message_phase(s);
365     assert(s->cmdfifo_cdb_offset == 0);
366     do_command_phase(s);
367 }
368 
369 static void satn_pdma_cb(ESPState *s)
370 {
371     uint8_t buf[ESP_FIFO_SZ];
372     int n;
373 
374     /* Copy FIFO into cmdfifo */
375     n = esp_fifo_pop_buf(&s->fifo, buf, fifo8_num_used(&s->fifo));
376     n = MIN(fifo8_num_free(&s->cmdfifo), n);
377     fifo8_push_all(&s->cmdfifo, buf, n);
378 
379     if (!esp_get_tc(s) && !fifo8_is_empty(&s->cmdfifo)) {
380         s->cmdfifo_cdb_offset = 1;
381         s->do_cmd = 0;
382         do_cmd(s);
383     }
384 }
385 
386 static void handle_satn(ESPState *s)
387 {
388     int32_t cmdlen;
389 
390     if (s->dma && !s->dma_enabled) {
391         s->dma_cb = handle_satn;
392         return;
393     }
394     esp_set_pdma_cb(s, SATN_PDMA_CB);
395     if (esp_select(s) < 0) {
396         return;
397     }
398     cmdlen = get_cmd(s, ESP_CMDFIFO_SZ);
399     if (cmdlen > 0) {
400         s->cmdfifo_cdb_offset = 1;
401         s->do_cmd = 0;
402         do_cmd(s);
403     } else if (cmdlen == 0) {
404         if (s->dma) {
405             esp_raise_drq(s);
406         }
407         s->do_cmd = 1;
408         /* Target present, but no cmd yet - switch to command phase */
409         s->rregs[ESP_RSEQ] = SEQ_CD;
410         esp_set_phase(s, STAT_CD);
411     }
412 }
413 
414 static void s_without_satn_pdma_cb(ESPState *s)
415 {
416     uint8_t buf[ESP_FIFO_SZ];
417     int n;
418 
419     /* Copy FIFO into cmdfifo */
420     n = esp_fifo_pop_buf(&s->fifo, buf, fifo8_num_used(&s->fifo));
421     n = MIN(fifo8_num_free(&s->cmdfifo), n);
422     fifo8_push_all(&s->cmdfifo, buf, n);
423 
424     if (!esp_get_tc(s) && !fifo8_is_empty(&s->cmdfifo)) {
425         s->cmdfifo_cdb_offset = 0;
426         s->do_cmd = 0;
427         do_cmd(s);
428     }
429 }
430 
431 static void handle_s_without_atn(ESPState *s)
432 {
433     int32_t cmdlen;
434 
435     if (s->dma && !s->dma_enabled) {
436         s->dma_cb = handle_s_without_atn;
437         return;
438     }
439     esp_set_pdma_cb(s, S_WITHOUT_SATN_PDMA_CB);
440     if (esp_select(s) < 0) {
441         return;
442     }
443     cmdlen = get_cmd(s, ESP_CMDFIFO_SZ);
444     if (cmdlen > 0) {
445         s->cmdfifo_cdb_offset = 0;
446         s->do_cmd = 0;
447         do_cmd(s);
448     } else if (cmdlen == 0) {
449         if (s->dma) {
450             esp_raise_drq(s);
451         }
452         s->do_cmd = 1;
453         /* Target present, but no cmd yet - switch to command phase */
454         s->rregs[ESP_RSEQ] = SEQ_CD;
455         esp_set_phase(s, STAT_CD);
456     }
457 }
458 
459 static void satn_stop_pdma_cb(ESPState *s)
460 {
461     uint8_t buf[ESP_FIFO_SZ];
462     int n;
463 
464     /* Copy FIFO into cmdfifo */
465     n = esp_fifo_pop_buf(&s->fifo, buf, fifo8_num_used(&s->fifo));
466     n = MIN(fifo8_num_free(&s->cmdfifo), n);
467     fifo8_push_all(&s->cmdfifo, buf, n);
468 
469     if (!esp_get_tc(s) && !fifo8_is_empty(&s->cmdfifo)) {
470         trace_esp_handle_satn_stop(fifo8_num_used(&s->cmdfifo));
471         s->do_cmd = 1;
472         s->cmdfifo_cdb_offset = 1;
473         esp_set_phase(s, STAT_CD);
474         s->rregs[ESP_RSTAT] |= STAT_TC;
475         s->rregs[ESP_RINTR] |= INTR_BS | INTR_FC;
476         s->rregs[ESP_RSEQ] = SEQ_CD;
477         esp_raise_irq(s);
478     }
479 }
480 
481 static void handle_satn_stop(ESPState *s)
482 {
483     int32_t cmdlen;
484 
485     if (s->dma && !s->dma_enabled) {
486         s->dma_cb = handle_satn_stop;
487         return;
488     }
489     esp_set_pdma_cb(s, SATN_STOP_PDMA_CB);
490     if (esp_select(s) < 0) {
491         return;
492     }
493     cmdlen = get_cmd(s, 1);
494     if (cmdlen > 0) {
495         trace_esp_handle_satn_stop(fifo8_num_used(&s->cmdfifo));
496         s->do_cmd = 1;
497         s->cmdfifo_cdb_offset = 1;
498         esp_set_phase(s, STAT_MO);
499         s->rregs[ESP_RINTR] |= INTR_BS | INTR_FC;
500         s->rregs[ESP_RSEQ] = SEQ_MO;
501         esp_raise_irq(s);
502     } else if (cmdlen == 0) {
503         if (s->dma) {
504             esp_raise_drq(s);
505         }
506         s->do_cmd = 1;
507         /* Target present, switch to message out phase */
508         s->rregs[ESP_RSEQ] = SEQ_MO;
509         esp_set_phase(s, STAT_MO);
510     }
511 }
512 
513 static void write_response_pdma_cb(ESPState *s)
514 {
515     esp_set_phase(s, STAT_ST);
516     s->rregs[ESP_RSTAT] |= STAT_TC;
517     s->rregs[ESP_RINTR] |= INTR_BS | INTR_FC;
518     s->rregs[ESP_RSEQ] = SEQ_CD;
519     esp_raise_irq(s);
520 }
521 
522 static void write_response(ESPState *s)
523 {
524     uint8_t buf[2];
525 
526     trace_esp_write_response(s->status);
527 
528     buf[0] = s->status;
529     buf[1] = 0;
530 
531     if (s->dma) {
532         if (s->dma_memory_write) {
533             s->dma_memory_write(s->dma_opaque, buf, 2);
534             esp_set_phase(s, STAT_ST);
535             s->rregs[ESP_RSTAT] |= STAT_TC;
536             s->rregs[ESP_RINTR] |= INTR_BS | INTR_FC;
537             s->rregs[ESP_RSEQ] = SEQ_CD;
538         } else {
539             esp_set_pdma_cb(s, WRITE_RESPONSE_PDMA_CB);
540             esp_raise_drq(s);
541             return;
542         }
543     } else {
544         fifo8_reset(&s->fifo);
545         fifo8_push_all(&s->fifo, buf, 2);
546         s->rregs[ESP_RFLAGS] = 2;
547     }
548     esp_raise_irq(s);
549 }
550 
551 static void esp_dma_done(ESPState *s)
552 {
553     s->rregs[ESP_RSTAT] |= STAT_TC;
554     s->rregs[ESP_RINTR] |= INTR_BS;
555     s->rregs[ESP_RFLAGS] = 0;
556     esp_set_tc(s, 0);
557     esp_raise_irq(s);
558 }
559 
560 static void do_dma_pdma_cb(ESPState *s)
561 {
562     int to_device = ((s->rregs[ESP_RSTAT] & 7) == STAT_DO);
563     uint8_t buf[ESP_CMDFIFO_SZ];
564     int len;
565     uint32_t n;
566 
567     if (s->do_cmd) {
568         /* Copy FIFO into cmdfifo */
569         n = esp_fifo_pop_buf(&s->fifo, buf, fifo8_num_used(&s->fifo));
570         n = MIN(fifo8_num_free(&s->cmdfifo), n);
571         fifo8_push_all(&s->cmdfifo, buf, n);
572 
573         /* Ensure we have received complete command after SATN and stop */
574         if (esp_get_tc(s) || fifo8_is_empty(&s->cmdfifo)) {
575             return;
576         }
577 
578         s->ti_size = 0;
579         if ((s->rregs[ESP_RSTAT] & 7) == STAT_CD) {
580             /* No command received */
581             if (s->cmdfifo_cdb_offset == fifo8_num_used(&s->cmdfifo)) {
582                 return;
583             }
584 
585             /* Command has been received */
586             s->do_cmd = 0;
587             do_cmd(s);
588         } else {
589             /*
590              * Extra message out bytes received: update cmdfifo_cdb_offset
591              * and then switch to command phase
592              */
593             s->cmdfifo_cdb_offset = fifo8_num_used(&s->cmdfifo);
594             esp_set_phase(s, STAT_CD);
595             s->rregs[ESP_RSTAT] |= STAT_TC;
596             s->rregs[ESP_RSEQ] = SEQ_CD;
597             s->rregs[ESP_RINTR] |= INTR_BS;
598             esp_raise_irq(s);
599         }
600         return;
601     }
602 
603     if (!s->current_req) {
604         return;
605     }
606 
607     if (to_device) {
608         /* Copy FIFO data to device */
609         len = MIN(s->async_len, ESP_FIFO_SZ);
610         len = MIN(len, fifo8_num_used(&s->fifo));
611         n = esp_fifo_pop_buf(&s->fifo, s->async_buf, len);
612         s->async_buf += n;
613         s->async_len -= n;
614         s->ti_size += n;
615 
616         if (n < len) {
617             /* Unaligned accesses can cause FIFO wraparound */
618             len = len - n;
619             n = esp_fifo_pop_buf(&s->fifo, s->async_buf, len);
620             s->async_buf += n;
621             s->async_len -= n;
622             s->ti_size += n;
623         }
624 
625         if (s->async_len == 0) {
626             scsi_req_continue(s->current_req);
627             return;
628         }
629 
630         if (esp_get_tc(s) == 0) {
631             esp_lower_drq(s);
632             esp_dma_done(s);
633         }
634 
635         return;
636     } else {
637         if (s->async_len == 0) {
638             /* Defer until the scsi layer has completed */
639             scsi_req_continue(s->current_req);
640             s->data_in_ready = false;
641             return;
642         }
643 
644         if (esp_get_tc(s) == 0) {
645             esp_lower_drq(s);
646             esp_dma_done(s);
647         }
648 
649         /* Copy device data to FIFO */
650         len = MIN(s->async_len, esp_get_tc(s));
651         len = MIN(len, fifo8_num_free(&s->fifo));
652         fifo8_push_all(&s->fifo, s->async_buf, len);
653         s->async_buf += len;
654         s->async_len -= len;
655         s->ti_size -= len;
656         esp_set_tc(s, esp_get_tc(s) - len);
657     }
658 }
659 
660 static void esp_do_dma(ESPState *s)
661 {
662     uint32_t len, cmdlen;
663     int to_device = ((s->rregs[ESP_RSTAT] & 7) == STAT_DO);
664     uint8_t buf[ESP_CMDFIFO_SZ];
665 
666     len = esp_get_tc(s);
667     if (s->do_cmd) {
668         /*
669          * handle_ti_cmd() case: esp_do_dma() is called only from
670          * handle_ti_cmd() with do_cmd != NULL (see the assert())
671          */
672         cmdlen = fifo8_num_used(&s->cmdfifo);
673         trace_esp_do_dma(cmdlen, len);
674         if (s->dma_memory_read) {
675             len = MIN(len, fifo8_num_free(&s->cmdfifo));
676             s->dma_memory_read(s->dma_opaque, buf, len);
677             fifo8_push_all(&s->cmdfifo, buf, len);
678             esp_set_tc(s, esp_get_tc(s) - len);
679         } else {
680             esp_set_pdma_cb(s, DO_DMA_PDMA_CB);
681             esp_raise_drq(s);
682             return;
683         }
684         trace_esp_handle_ti_cmd(cmdlen);
685         s->ti_size = 0;
686         if ((s->rregs[ESP_RSTAT] & 7) == STAT_CD) {
687             /* No command received */
688             if (s->cmdfifo_cdb_offset == fifo8_num_used(&s->cmdfifo)) {
689                 return;
690             }
691 
692             /* Command has been received */
693             s->do_cmd = 0;
694             do_cmd(s);
695         } else {
696             /*
697              * Extra message out bytes received: update cmdfifo_cdb_offset
698              * and then switch to command phase
699              */
700             s->cmdfifo_cdb_offset = fifo8_num_used(&s->cmdfifo);
701             esp_set_phase(s, STAT_CD);
702             s->rregs[ESP_RSTAT] |= STAT_TC;
703             s->rregs[ESP_RSEQ] = SEQ_CD;
704             s->rregs[ESP_RINTR] |= INTR_BS;
705             esp_raise_irq(s);
706         }
707         return;
708     }
709     if (!s->current_req) {
710         return;
711     }
712     if (s->async_len == 0) {
713         /* Defer until data is available.  */
714         return;
715     }
716     if (len > s->async_len) {
717         len = s->async_len;
718     }
719     if (to_device) {
720         if (s->dma_memory_read) {
721             s->dma_memory_read(s->dma_opaque, s->async_buf, len);
722 
723             esp_set_tc(s, esp_get_tc(s) - len);
724             s->async_buf += len;
725             s->async_len -= len;
726             s->ti_size += len;
727 
728             if (s->async_len == 0) {
729                 scsi_req_continue(s->current_req);
730                 /*
731                  * If there is still data to be read from the device then
732                  * complete the DMA operation immediately.  Otherwise defer
733                  * until the scsi layer has completed.
734                  */
735                 return;
736             }
737 
738             /* Partially filled a scsi buffer. Complete immediately.  */
739             esp_dma_done(s);
740             esp_lower_drq(s);
741         } else {
742             esp_set_pdma_cb(s, DO_DMA_PDMA_CB);
743             esp_raise_drq(s);
744         }
745     } else {
746         if (s->dma_memory_write) {
747             s->dma_memory_write(s->dma_opaque, s->async_buf, len);
748 
749             esp_set_tc(s, esp_get_tc(s) - len);
750             s->async_buf += len;
751             s->async_len -= len;
752             s->ti_size -= len;
753 
754             if (s->async_len == 0) {
755                 scsi_req_continue(s->current_req);
756                 /*
757                  * If there is still data to be read from the device then
758                  * complete the DMA operation immediately.  Otherwise defer
759                  * until the scsi layer has completed.
760                  */
761                 if (esp_get_tc(s) != 0 || s->ti_size == 0) {
762                     return;
763                 }
764             }
765 
766             /* Partially filled a scsi buffer. Complete immediately.  */
767             esp_dma_done(s);
768             esp_lower_drq(s);
769         } else {
770             /* Adjust TC for any leftover data in the FIFO */
771             if (!fifo8_is_empty(&s->fifo)) {
772                 esp_set_tc(s, esp_get_tc(s) - fifo8_num_used(&s->fifo));
773             }
774 
775             /* Copy device data to FIFO */
776             len = MIN(len, fifo8_num_free(&s->fifo));
777             fifo8_push_all(&s->fifo, s->async_buf, len);
778             s->async_buf += len;
779             s->async_len -= len;
780             s->ti_size -= len;
781 
782             /*
783              * MacOS toolbox uses a TI length of 16 bytes for all commands, so
784              * commands shorter than this must be padded accordingly
785              */
786             if (len < esp_get_tc(s) && esp_get_tc(s) <= ESP_FIFO_SZ) {
787                 while (fifo8_num_used(&s->fifo) < ESP_FIFO_SZ) {
788                     esp_fifo_push(&s->fifo, 0);
789                     len++;
790                 }
791             }
792 
793             esp_set_tc(s, esp_get_tc(s) - len);
794             esp_set_pdma_cb(s, DO_DMA_PDMA_CB);
795             esp_raise_drq(s);
796         }
797     }
798 }
799 
800 static void esp_do_nodma(ESPState *s)
801 {
802     int to_device = ((s->rregs[ESP_RSTAT] & 7) == STAT_DO);
803     uint8_t buf[ESP_FIFO_SZ];
804     uint32_t cmdlen;
805     int len, n;
806 
807     if (s->do_cmd) {
808         /* Copy FIFO into cmdfifo */
809         n = esp_fifo_pop_buf(&s->fifo, buf, fifo8_num_used(&s->fifo));
810         n = MIN(fifo8_num_free(&s->cmdfifo), n);
811         fifo8_push_all(&s->cmdfifo, buf, n);
812 
813         cmdlen = fifo8_num_used(&s->cmdfifo);
814         trace_esp_handle_ti_cmd(cmdlen);
815         s->ti_size = 0;
816         if ((s->rregs[ESP_RSTAT] & 7) == STAT_CD) {
817             /* No command received */
818             if (s->cmdfifo_cdb_offset == fifo8_num_used(&s->cmdfifo)) {
819                 return;
820             }
821 
822             /* Command has been received */
823             s->do_cmd = 0;
824             do_cmd(s);
825         } else {
826             /*
827              * Extra message out bytes received: update cmdfifo_cdb_offset
828              * and then switch to command phase
829              */
830             s->cmdfifo_cdb_offset = fifo8_num_used(&s->cmdfifo);
831             esp_set_phase(s, STAT_CD);
832             s->rregs[ESP_RSTAT] |= STAT_TC;
833             s->rregs[ESP_RSEQ] = SEQ_CD;
834             s->rregs[ESP_RINTR] |= INTR_BS;
835             esp_raise_irq(s);
836         }
837         return;
838     }
839 
840     if (!s->current_req) {
841         return;
842     }
843 
844     if (s->async_len == 0) {
845         /* Defer until data is available.  */
846         return;
847     }
848 
849     if (to_device) {
850         len = MIN(s->async_len, ESP_FIFO_SZ);
851         len = MIN(len, fifo8_num_used(&s->fifo));
852         esp_fifo_pop_buf(&s->fifo, s->async_buf, len);
853         s->async_buf += len;
854         s->async_len -= len;
855         s->ti_size += len;
856     } else {
857         if (fifo8_is_empty(&s->fifo)) {
858             fifo8_push(&s->fifo, s->async_buf[0]);
859             s->async_buf++;
860             s->async_len--;
861             s->ti_size--;
862         }
863     }
864 
865     if (s->async_len == 0) {
866         scsi_req_continue(s->current_req);
867         return;
868     }
869 
870     s->rregs[ESP_RINTR] |= INTR_BS;
871     esp_raise_irq(s);
872 }
873 
874 static void esp_pdma_cb(ESPState *s)
875 {
876     switch (s->pdma_cb) {
877     case SATN_PDMA_CB:
878         satn_pdma_cb(s);
879         break;
880     case S_WITHOUT_SATN_PDMA_CB:
881         s_without_satn_pdma_cb(s);
882         break;
883     case SATN_STOP_PDMA_CB:
884         satn_stop_pdma_cb(s);
885         break;
886     case WRITE_RESPONSE_PDMA_CB:
887         write_response_pdma_cb(s);
888         break;
889     case DO_DMA_PDMA_CB:
890         do_dma_pdma_cb(s);
891         break;
892     default:
893         g_assert_not_reached();
894     }
895 }
896 
897 void esp_command_complete(SCSIRequest *req, size_t resid)
898 {
899     ESPState *s = req->hba_private;
900     int to_device = ((s->rregs[ESP_RSTAT] & 7) == STAT_DO);
901 
902     trace_esp_command_complete();
903 
904     /*
905      * Non-DMA transfers from the target will leave the last byte in
906      * the FIFO so don't reset ti_size in this case
907      */
908     if (s->dma || to_device) {
909         if (s->ti_size != 0) {
910             trace_esp_command_complete_unexpected();
911         }
912         s->ti_size = 0;
913     }
914 
915     s->async_len = 0;
916     if (req->status) {
917         trace_esp_command_complete_fail();
918     }
919     s->status = req->status;
920 
921     /*
922      * If the transfer is finished, switch to status phase. For non-DMA
923      * transfers from the target the last byte is still in the FIFO
924      */
925     if (s->ti_size == 0) {
926         esp_set_phase(s, STAT_ST);
927         esp_dma_done(s);
928         esp_lower_drq(s);
929     }
930 
931     if (s->current_req) {
932         scsi_req_unref(s->current_req);
933         s->current_req = NULL;
934         s->current_dev = NULL;
935     }
936 }
937 
938 void esp_transfer_data(SCSIRequest *req, uint32_t len)
939 {
940     ESPState *s = req->hba_private;
941     int to_device = ((s->rregs[ESP_RSTAT] & 7) == STAT_DO);
942     uint32_t dmalen = esp_get_tc(s);
943 
944     assert(!s->do_cmd);
945     trace_esp_transfer_data(dmalen, s->ti_size);
946     s->async_len = len;
947     s->async_buf = scsi_req_get_buf(req);
948 
949     if (!to_device && !s->data_in_ready) {
950         /*
951          * Initial incoming data xfer is complete so raise command
952          * completion interrupt
953          */
954         s->data_in_ready = true;
955         s->rregs[ESP_RSTAT] |= STAT_TC;
956         s->rregs[ESP_RINTR] |= INTR_BS;
957         esp_raise_irq(s);
958     }
959 
960     if (s->ti_cmd == 0) {
961         /*
962          * Always perform the initial transfer upon reception of the next TI
963          * command to ensure the DMA/non-DMA status of the command is correct.
964          * It is not possible to use s->dma directly in the section below as
965          * some OSs send non-DMA NOP commands after a DMA transfer. Hence if the
966          * async data transfer is delayed then s->dma is set incorrectly.
967          */
968         return;
969     }
970 
971     if (s->ti_cmd == (CMD_TI | CMD_DMA)) {
972         if (dmalen) {
973             esp_do_dma(s);
974         } else if (s->ti_size <= 0) {
975             /*
976              * If this was the last part of a DMA transfer then the
977              * completion interrupt is deferred to here.
978              */
979             esp_dma_done(s);
980             esp_lower_drq(s);
981         }
982     } else if (s->ti_cmd == CMD_TI) {
983         esp_do_nodma(s);
984     }
985 }
986 
987 static void handle_ti(ESPState *s)
988 {
989     uint32_t dmalen;
990 
991     if (s->dma && !s->dma_enabled) {
992         s->dma_cb = handle_ti;
993         return;
994     }
995 
996     s->ti_cmd = s->rregs[ESP_CMD];
997     if (s->dma) {
998         dmalen = esp_get_tc(s);
999         trace_esp_handle_ti(dmalen);
1000         s->rregs[ESP_RSTAT] &= ~STAT_TC;
1001         esp_do_dma(s);
1002     } else {
1003         trace_esp_handle_ti(s->ti_size);
1004         esp_do_nodma(s);
1005     }
1006 }
1007 
1008 void esp_hard_reset(ESPState *s)
1009 {
1010     memset(s->rregs, 0, ESP_REGS);
1011     memset(s->wregs, 0, ESP_REGS);
1012     s->tchi_written = 0;
1013     s->ti_size = 0;
1014     s->async_len = 0;
1015     fifo8_reset(&s->fifo);
1016     fifo8_reset(&s->cmdfifo);
1017     s->dma = 0;
1018     s->do_cmd = 0;
1019     s->dma_cb = NULL;
1020 
1021     s->rregs[ESP_CFG1] = 7;
1022 }
1023 
1024 static void esp_soft_reset(ESPState *s)
1025 {
1026     qemu_irq_lower(s->irq);
1027     qemu_irq_lower(s->irq_data);
1028     esp_hard_reset(s);
1029 }
1030 
1031 static void esp_bus_reset(ESPState *s)
1032 {
1033     bus_cold_reset(BUS(&s->bus));
1034 }
1035 
1036 static void parent_esp_reset(ESPState *s, int irq, int level)
1037 {
1038     if (level) {
1039         esp_soft_reset(s);
1040     }
1041 }
1042 
1043 static void esp_run_cmd(ESPState *s)
1044 {
1045     uint8_t cmd = s->rregs[ESP_CMD];
1046 
1047     if (cmd & CMD_DMA) {
1048         s->dma = 1;
1049         /* Reload DMA counter.  */
1050         if (esp_get_stc(s) == 0) {
1051             esp_set_tc(s, 0x10000);
1052         } else {
1053             esp_set_tc(s, esp_get_stc(s));
1054         }
1055     } else {
1056         s->dma = 0;
1057     }
1058     switch (cmd & CMD_CMD) {
1059     case CMD_NOP:
1060         trace_esp_mem_writeb_cmd_nop(cmd);
1061         break;
1062     case CMD_FLUSH:
1063         trace_esp_mem_writeb_cmd_flush(cmd);
1064         fifo8_reset(&s->fifo);
1065         break;
1066     case CMD_RESET:
1067         trace_esp_mem_writeb_cmd_reset(cmd);
1068         esp_soft_reset(s);
1069         break;
1070     case CMD_BUSRESET:
1071         trace_esp_mem_writeb_cmd_bus_reset(cmd);
1072         esp_bus_reset(s);
1073         if (!(s->wregs[ESP_CFG1] & CFG1_RESREPT)) {
1074             s->rregs[ESP_RINTR] |= INTR_RST;
1075             esp_raise_irq(s);
1076         }
1077         break;
1078     case CMD_TI:
1079         trace_esp_mem_writeb_cmd_ti(cmd);
1080         handle_ti(s);
1081         break;
1082     case CMD_ICCS:
1083         trace_esp_mem_writeb_cmd_iccs(cmd);
1084         write_response(s);
1085         s->rregs[ESP_RINTR] |= INTR_FC;
1086         esp_set_phase(s, STAT_MI);
1087         break;
1088     case CMD_MSGACC:
1089         trace_esp_mem_writeb_cmd_msgacc(cmd);
1090         s->rregs[ESP_RINTR] |= INTR_DC;
1091         s->rregs[ESP_RSEQ] = 0;
1092         s->rregs[ESP_RFLAGS] = 0;
1093         esp_raise_irq(s);
1094         break;
1095     case CMD_PAD:
1096         trace_esp_mem_writeb_cmd_pad(cmd);
1097         s->rregs[ESP_RSTAT] = STAT_TC;
1098         s->rregs[ESP_RINTR] |= INTR_FC;
1099         s->rregs[ESP_RSEQ] = 0;
1100         break;
1101     case CMD_SATN:
1102         trace_esp_mem_writeb_cmd_satn(cmd);
1103         break;
1104     case CMD_RSTATN:
1105         trace_esp_mem_writeb_cmd_rstatn(cmd);
1106         break;
1107     case CMD_SEL:
1108         trace_esp_mem_writeb_cmd_sel(cmd);
1109         handle_s_without_atn(s);
1110         break;
1111     case CMD_SELATN:
1112         trace_esp_mem_writeb_cmd_selatn(cmd);
1113         handle_satn(s);
1114         break;
1115     case CMD_SELATNS:
1116         trace_esp_mem_writeb_cmd_selatns(cmd);
1117         handle_satn_stop(s);
1118         break;
1119     case CMD_ENSEL:
1120         trace_esp_mem_writeb_cmd_ensel(cmd);
1121         s->rregs[ESP_RINTR] = 0;
1122         break;
1123     case CMD_DISSEL:
1124         trace_esp_mem_writeb_cmd_dissel(cmd);
1125         s->rregs[ESP_RINTR] = 0;
1126         esp_raise_irq(s);
1127         break;
1128     default:
1129         trace_esp_error_unhandled_command(cmd);
1130         break;
1131     }
1132 }
1133 
1134 uint64_t esp_reg_read(ESPState *s, uint32_t saddr)
1135 {
1136     uint32_t val;
1137 
1138     switch (saddr) {
1139     case ESP_FIFO:
1140         if (s->dma_memory_read && s->dma_memory_write &&
1141                 (s->rregs[ESP_RSTAT] & STAT_PIO_MASK) == 0) {
1142             /* Data out.  */
1143             qemu_log_mask(LOG_UNIMP, "esp: PIO data read not implemented\n");
1144             s->rregs[ESP_FIFO] = 0;
1145         } else {
1146             if ((s->rregs[ESP_RSTAT] & 0x7) == STAT_DI) {
1147                 if (s->ti_size) {
1148                     esp_do_nodma(s);
1149                 } else {
1150                     /*
1151                      * The last byte of a non-DMA transfer has been read out
1152                      * of the FIFO so switch to status phase
1153                      */
1154                     esp_set_phase(s, STAT_ST);
1155                     s->rregs[ESP_RSTAT] |= STAT_TC;
1156                 }
1157             }
1158             s->rregs[ESP_FIFO] = esp_fifo_pop(&s->fifo);
1159         }
1160         val = s->rregs[ESP_FIFO];
1161         break;
1162     case ESP_RINTR:
1163         /*
1164          * Clear sequence step, interrupt register and all status bits
1165          * except TC
1166          */
1167         val = s->rregs[ESP_RINTR];
1168         s->rregs[ESP_RINTR] = 0;
1169         s->rregs[ESP_RSTAT] &= ~STAT_TC;
1170         /*
1171          * According to the datasheet ESP_RSEQ should be cleared, but as the
1172          * emulation currently defers information transfers to the next TI
1173          * command leave it for now so that pedantic guests such as the old
1174          * Linux 2.6 driver see the correct flags before the next SCSI phase
1175          * transition.
1176          *
1177          * s->rregs[ESP_RSEQ] = SEQ_0;
1178          */
1179         esp_lower_irq(s);
1180         break;
1181     case ESP_TCHI:
1182         /* Return the unique id if the value has never been written */
1183         if (!s->tchi_written) {
1184             val = s->chip_id;
1185         } else {
1186             val = s->rregs[saddr];
1187         }
1188         break;
1189      case ESP_RFLAGS:
1190         /* Bottom 5 bits indicate number of bytes in FIFO */
1191         val = fifo8_num_used(&s->fifo);
1192         break;
1193     default:
1194         val = s->rregs[saddr];
1195         break;
1196     }
1197 
1198     trace_esp_mem_readb(saddr, val);
1199     return val;
1200 }
1201 
1202 void esp_reg_write(ESPState *s, uint32_t saddr, uint64_t val)
1203 {
1204     trace_esp_mem_writeb(saddr, s->wregs[saddr], val);
1205     switch (saddr) {
1206     case ESP_TCHI:
1207         s->tchi_written = true;
1208         /* fall through */
1209     case ESP_TCLO:
1210     case ESP_TCMID:
1211         s->rregs[ESP_RSTAT] &= ~STAT_TC;
1212         break;
1213     case ESP_FIFO:
1214         if (s->do_cmd) {
1215             if (!fifo8_is_full(&s->fifo)) {
1216                 esp_fifo_push(&s->fifo, val);
1217                 esp_fifo_push(&s->cmdfifo, fifo8_pop(&s->fifo));
1218             }
1219 
1220             /*
1221              * If any unexpected message out/command phase data is
1222              * transferred using non-DMA, raise the interrupt
1223              */
1224             if (s->rregs[ESP_CMD] == CMD_TI) {
1225                 s->rregs[ESP_RINTR] |= INTR_BS;
1226                 esp_raise_irq(s);
1227             }
1228         } else {
1229             esp_fifo_push(&s->fifo, val);
1230         }
1231         break;
1232     case ESP_CMD:
1233         s->rregs[saddr] = val;
1234         esp_run_cmd(s);
1235         break;
1236     case ESP_WBUSID ... ESP_WSYNO:
1237         break;
1238     case ESP_CFG1:
1239     case ESP_CFG2: case ESP_CFG3:
1240     case ESP_RES3: case ESP_RES4:
1241         s->rregs[saddr] = val;
1242         break;
1243     case ESP_WCCF ... ESP_WTEST:
1244         break;
1245     default:
1246         trace_esp_error_invalid_write(val, saddr);
1247         return;
1248     }
1249     s->wregs[saddr] = val;
1250 }
1251 
1252 static bool esp_mem_accepts(void *opaque, hwaddr addr,
1253                             unsigned size, bool is_write,
1254                             MemTxAttrs attrs)
1255 {
1256     return (size == 1) || (is_write && size == 4);
1257 }
1258 
1259 static bool esp_is_before_version_5(void *opaque, int version_id)
1260 {
1261     ESPState *s = ESP(opaque);
1262 
1263     version_id = MIN(version_id, s->mig_version_id);
1264     return version_id < 5;
1265 }
1266 
1267 static bool esp_is_version_5(void *opaque, int version_id)
1268 {
1269     ESPState *s = ESP(opaque);
1270 
1271     version_id = MIN(version_id, s->mig_version_id);
1272     return version_id >= 5;
1273 }
1274 
1275 static bool esp_is_version_6(void *opaque, int version_id)
1276 {
1277     ESPState *s = ESP(opaque);
1278 
1279     version_id = MIN(version_id, s->mig_version_id);
1280     return version_id >= 6;
1281 }
1282 
1283 int esp_pre_save(void *opaque)
1284 {
1285     ESPState *s = ESP(object_resolve_path_component(
1286                       OBJECT(opaque), "esp"));
1287 
1288     s->mig_version_id = vmstate_esp.version_id;
1289     return 0;
1290 }
1291 
1292 static int esp_post_load(void *opaque, int version_id)
1293 {
1294     ESPState *s = ESP(opaque);
1295     int len, i;
1296 
1297     version_id = MIN(version_id, s->mig_version_id);
1298 
1299     if (version_id < 5) {
1300         esp_set_tc(s, s->mig_dma_left);
1301 
1302         /* Migrate ti_buf to fifo */
1303         len = s->mig_ti_wptr - s->mig_ti_rptr;
1304         for (i = 0; i < len; i++) {
1305             fifo8_push(&s->fifo, s->mig_ti_buf[i]);
1306         }
1307 
1308         /* Migrate cmdbuf to cmdfifo */
1309         for (i = 0; i < s->mig_cmdlen; i++) {
1310             fifo8_push(&s->cmdfifo, s->mig_cmdbuf[i]);
1311         }
1312     }
1313 
1314     s->mig_version_id = vmstate_esp.version_id;
1315     return 0;
1316 }
1317 
1318 /*
1319  * PDMA (or pseudo-DMA) is only used on the Macintosh and requires the
1320  * guest CPU to perform the transfers between the SCSI bus and memory
1321  * itself. This is indicated by the dma_memory_read and dma_memory_write
1322  * functions being NULL (in contrast to the ESP PCI device) whilst
1323  * dma_enabled is still set.
1324  */
1325 
1326 static bool esp_pdma_needed(void *opaque)
1327 {
1328     ESPState *s = ESP(opaque);
1329 
1330     return s->dma_memory_read == NULL && s->dma_memory_write == NULL &&
1331            s->dma_enabled;
1332 }
1333 
1334 static const VMStateDescription vmstate_esp_pdma = {
1335     .name = "esp/pdma",
1336     .version_id = 0,
1337     .minimum_version_id = 0,
1338     .needed = esp_pdma_needed,
1339     .fields = (const VMStateField[]) {
1340         VMSTATE_UINT8(pdma_cb, ESPState),
1341         VMSTATE_END_OF_LIST()
1342     }
1343 };
1344 
1345 const VMStateDescription vmstate_esp = {
1346     .name = "esp",
1347     .version_id = 6,
1348     .minimum_version_id = 3,
1349     .post_load = esp_post_load,
1350     .fields = (const VMStateField[]) {
1351         VMSTATE_BUFFER(rregs, ESPState),
1352         VMSTATE_BUFFER(wregs, ESPState),
1353         VMSTATE_INT32(ti_size, ESPState),
1354         VMSTATE_UINT32_TEST(mig_ti_rptr, ESPState, esp_is_before_version_5),
1355         VMSTATE_UINT32_TEST(mig_ti_wptr, ESPState, esp_is_before_version_5),
1356         VMSTATE_BUFFER_TEST(mig_ti_buf, ESPState, esp_is_before_version_5),
1357         VMSTATE_UINT32(status, ESPState),
1358         VMSTATE_UINT32_TEST(mig_deferred_status, ESPState,
1359                             esp_is_before_version_5),
1360         VMSTATE_BOOL_TEST(mig_deferred_complete, ESPState,
1361                           esp_is_before_version_5),
1362         VMSTATE_UINT32(dma, ESPState),
1363         VMSTATE_STATIC_BUFFER(mig_cmdbuf, ESPState, 0,
1364                               esp_is_before_version_5, 0, 16),
1365         VMSTATE_STATIC_BUFFER(mig_cmdbuf, ESPState, 4,
1366                               esp_is_before_version_5, 16,
1367                               sizeof(typeof_field(ESPState, mig_cmdbuf))),
1368         VMSTATE_UINT32_TEST(mig_cmdlen, ESPState, esp_is_before_version_5),
1369         VMSTATE_UINT32(do_cmd, ESPState),
1370         VMSTATE_UINT32_TEST(mig_dma_left, ESPState, esp_is_before_version_5),
1371         VMSTATE_BOOL_TEST(data_in_ready, ESPState, esp_is_version_5),
1372         VMSTATE_UINT8_TEST(cmdfifo_cdb_offset, ESPState, esp_is_version_5),
1373         VMSTATE_FIFO8_TEST(fifo, ESPState, esp_is_version_5),
1374         VMSTATE_FIFO8_TEST(cmdfifo, ESPState, esp_is_version_5),
1375         VMSTATE_UINT8_TEST(ti_cmd, ESPState, esp_is_version_5),
1376         VMSTATE_UINT8_TEST(lun, ESPState, esp_is_version_6),
1377         VMSTATE_END_OF_LIST()
1378     },
1379     .subsections = (const VMStateDescription * const []) {
1380         &vmstate_esp_pdma,
1381         NULL
1382     }
1383 };
1384 
1385 static void sysbus_esp_mem_write(void *opaque, hwaddr addr,
1386                                  uint64_t val, unsigned int size)
1387 {
1388     SysBusESPState *sysbus = opaque;
1389     ESPState *s = ESP(&sysbus->esp);
1390     uint32_t saddr;
1391 
1392     saddr = addr >> sysbus->it_shift;
1393     esp_reg_write(s, saddr, val);
1394 }
1395 
1396 static uint64_t sysbus_esp_mem_read(void *opaque, hwaddr addr,
1397                                     unsigned int size)
1398 {
1399     SysBusESPState *sysbus = opaque;
1400     ESPState *s = ESP(&sysbus->esp);
1401     uint32_t saddr;
1402 
1403     saddr = addr >> sysbus->it_shift;
1404     return esp_reg_read(s, saddr);
1405 }
1406 
1407 static const MemoryRegionOps sysbus_esp_mem_ops = {
1408     .read = sysbus_esp_mem_read,
1409     .write = sysbus_esp_mem_write,
1410     .endianness = DEVICE_NATIVE_ENDIAN,
1411     .valid.accepts = esp_mem_accepts,
1412 };
1413 
1414 static void sysbus_esp_pdma_write(void *opaque, hwaddr addr,
1415                                   uint64_t val, unsigned int size)
1416 {
1417     SysBusESPState *sysbus = opaque;
1418     ESPState *s = ESP(&sysbus->esp);
1419 
1420     trace_esp_pdma_write(size);
1421 
1422     switch (size) {
1423     case 1:
1424         esp_pdma_write(s, val);
1425         break;
1426     case 2:
1427         esp_pdma_write(s, val >> 8);
1428         esp_pdma_write(s, val);
1429         break;
1430     }
1431     esp_pdma_cb(s);
1432 }
1433 
1434 static uint64_t sysbus_esp_pdma_read(void *opaque, hwaddr addr,
1435                                      unsigned int size)
1436 {
1437     SysBusESPState *sysbus = opaque;
1438     ESPState *s = ESP(&sysbus->esp);
1439     uint64_t val = 0;
1440 
1441     trace_esp_pdma_read(size);
1442 
1443     switch (size) {
1444     case 1:
1445         val = esp_pdma_read(s);
1446         break;
1447     case 2:
1448         val = esp_pdma_read(s);
1449         val = (val << 8) | esp_pdma_read(s);
1450         break;
1451     }
1452     if (fifo8_num_used(&s->fifo) < 2) {
1453         esp_pdma_cb(s);
1454     }
1455     return val;
1456 }
1457 
1458 static void *esp_load_request(QEMUFile *f, SCSIRequest *req)
1459 {
1460     ESPState *s = container_of(req->bus, ESPState, bus);
1461 
1462     scsi_req_ref(req);
1463     s->current_req = req;
1464     return s;
1465 }
1466 
1467 static const MemoryRegionOps sysbus_esp_pdma_ops = {
1468     .read = sysbus_esp_pdma_read,
1469     .write = sysbus_esp_pdma_write,
1470     .endianness = DEVICE_NATIVE_ENDIAN,
1471     .valid.min_access_size = 1,
1472     .valid.max_access_size = 4,
1473     .impl.min_access_size = 1,
1474     .impl.max_access_size = 2,
1475 };
1476 
1477 static const struct SCSIBusInfo esp_scsi_info = {
1478     .tcq = false,
1479     .max_target = ESP_MAX_DEVS,
1480     .max_lun = 7,
1481 
1482     .load_request = esp_load_request,
1483     .transfer_data = esp_transfer_data,
1484     .complete = esp_command_complete,
1485     .cancel = esp_request_cancelled
1486 };
1487 
1488 static void sysbus_esp_gpio_demux(void *opaque, int irq, int level)
1489 {
1490     SysBusESPState *sysbus = SYSBUS_ESP(opaque);
1491     ESPState *s = ESP(&sysbus->esp);
1492 
1493     switch (irq) {
1494     case 0:
1495         parent_esp_reset(s, irq, level);
1496         break;
1497     case 1:
1498         esp_dma_enable(s, irq, level);
1499         break;
1500     }
1501 }
1502 
1503 static void sysbus_esp_realize(DeviceState *dev, Error **errp)
1504 {
1505     SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
1506     SysBusESPState *sysbus = SYSBUS_ESP(dev);
1507     ESPState *s = ESP(&sysbus->esp);
1508 
1509     if (!qdev_realize(DEVICE(s), NULL, errp)) {
1510         return;
1511     }
1512 
1513     sysbus_init_irq(sbd, &s->irq);
1514     sysbus_init_irq(sbd, &s->irq_data);
1515     assert(sysbus->it_shift != -1);
1516 
1517     s->chip_id = TCHI_FAS100A;
1518     memory_region_init_io(&sysbus->iomem, OBJECT(sysbus), &sysbus_esp_mem_ops,
1519                           sysbus, "esp-regs", ESP_REGS << sysbus->it_shift);
1520     sysbus_init_mmio(sbd, &sysbus->iomem);
1521     memory_region_init_io(&sysbus->pdma, OBJECT(sysbus), &sysbus_esp_pdma_ops,
1522                           sysbus, "esp-pdma", 4);
1523     sysbus_init_mmio(sbd, &sysbus->pdma);
1524 
1525     qdev_init_gpio_in(dev, sysbus_esp_gpio_demux, 2);
1526 
1527     scsi_bus_init(&s->bus, sizeof(s->bus), dev, &esp_scsi_info);
1528 }
1529 
1530 static void sysbus_esp_hard_reset(DeviceState *dev)
1531 {
1532     SysBusESPState *sysbus = SYSBUS_ESP(dev);
1533     ESPState *s = ESP(&sysbus->esp);
1534 
1535     esp_hard_reset(s);
1536 }
1537 
1538 static void sysbus_esp_init(Object *obj)
1539 {
1540     SysBusESPState *sysbus = SYSBUS_ESP(obj);
1541 
1542     object_initialize_child(obj, "esp", &sysbus->esp, TYPE_ESP);
1543 }
1544 
1545 static const VMStateDescription vmstate_sysbus_esp_scsi = {
1546     .name = "sysbusespscsi",
1547     .version_id = 2,
1548     .minimum_version_id = 1,
1549     .pre_save = esp_pre_save,
1550     .fields = (const VMStateField[]) {
1551         VMSTATE_UINT8_V(esp.mig_version_id, SysBusESPState, 2),
1552         VMSTATE_STRUCT(esp, SysBusESPState, 0, vmstate_esp, ESPState),
1553         VMSTATE_END_OF_LIST()
1554     }
1555 };
1556 
1557 static void sysbus_esp_class_init(ObjectClass *klass, void *data)
1558 {
1559     DeviceClass *dc = DEVICE_CLASS(klass);
1560 
1561     dc->realize = sysbus_esp_realize;
1562     dc->reset = sysbus_esp_hard_reset;
1563     dc->vmsd = &vmstate_sysbus_esp_scsi;
1564     set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
1565 }
1566 
1567 static const TypeInfo sysbus_esp_info = {
1568     .name          = TYPE_SYSBUS_ESP,
1569     .parent        = TYPE_SYS_BUS_DEVICE,
1570     .instance_init = sysbus_esp_init,
1571     .instance_size = sizeof(SysBusESPState),
1572     .class_init    = sysbus_esp_class_init,
1573 };
1574 
1575 static void esp_finalize(Object *obj)
1576 {
1577     ESPState *s = ESP(obj);
1578 
1579     fifo8_destroy(&s->fifo);
1580     fifo8_destroy(&s->cmdfifo);
1581 }
1582 
1583 static void esp_init(Object *obj)
1584 {
1585     ESPState *s = ESP(obj);
1586 
1587     fifo8_create(&s->fifo, ESP_FIFO_SZ);
1588     fifo8_create(&s->cmdfifo, ESP_CMDFIFO_SZ);
1589 }
1590 
1591 static void esp_class_init(ObjectClass *klass, void *data)
1592 {
1593     DeviceClass *dc = DEVICE_CLASS(klass);
1594 
1595     /* internal device for sysbusesp/pciespscsi, not user-creatable */
1596     dc->user_creatable = false;
1597     set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
1598 }
1599 
1600 static const TypeInfo esp_info = {
1601     .name = TYPE_ESP,
1602     .parent = TYPE_DEVICE,
1603     .instance_init = esp_init,
1604     .instance_finalize = esp_finalize,
1605     .instance_size = sizeof(ESPState),
1606     .class_init = esp_class_init,
1607 };
1608 
1609 static void esp_register_types(void)
1610 {
1611     type_register_static(&sysbus_esp_info);
1612     type_register_static(&esp_info);
1613 }
1614 
1615 type_init(esp_register_types)
1616