xref: /qemu/hw/scsi/esp.c (revision 6d97f5acbf029b9c3cbf75fb7102931c2afe8dd3)
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_get_phase(ESPState *s)
200 {
201     return s->rregs[ESP_RSTAT] & 7;
202 }
203 
204 static uint8_t esp_pdma_read(ESPState *s)
205 {
206     uint8_t val;
207 
208     val = esp_fifo_pop(&s->fifo);
209     return val;
210 }
211 
212 static void esp_pdma_write(ESPState *s, uint8_t val)
213 {
214     uint32_t dmalen = esp_get_tc(s);
215 
216     if (dmalen == 0) {
217         return;
218     }
219 
220     esp_fifo_push(&s->fifo, val);
221 
222     dmalen--;
223     esp_set_tc(s, dmalen);
224 }
225 
226 static void esp_set_pdma_cb(ESPState *s, enum pdma_cb cb)
227 {
228     s->pdma_cb = cb;
229 }
230 
231 static int esp_select(ESPState *s)
232 {
233     int target;
234 
235     target = s->wregs[ESP_WBUSID] & BUSID_DID;
236 
237     s->ti_size = 0;
238 
239     if (s->current_req) {
240         /* Started a new command before the old one finished. Cancel it. */
241         scsi_req_cancel(s->current_req);
242     }
243 
244     s->current_dev = scsi_device_find(&s->bus, 0, target, 0);
245     if (!s->current_dev) {
246         /* No such drive */
247         s->rregs[ESP_RSTAT] = 0;
248         s->rregs[ESP_RINTR] = INTR_DC;
249         s->rregs[ESP_RSEQ] = SEQ_0;
250         esp_raise_irq(s);
251         return -1;
252     }
253 
254     /*
255      * Note that we deliberately don't raise the IRQ here: this will be done
256      * either in do_command_phase() for DATA OUT transfers or by the deferred
257      * IRQ mechanism in esp_transfer_data() for DATA IN transfers
258      */
259     s->rregs[ESP_RINTR] |= INTR_FC;
260     s->rregs[ESP_RSEQ] = SEQ_CD;
261     return 0;
262 }
263 
264 static uint32_t get_cmd(ESPState *s, uint32_t maxlen)
265 {
266     uint8_t buf[ESP_CMDFIFO_SZ];
267     uint32_t dmalen, n;
268     int target;
269 
270     target = s->wregs[ESP_WBUSID] & BUSID_DID;
271     if (s->dma) {
272         dmalen = MIN(esp_get_tc(s), maxlen);
273         if (dmalen == 0) {
274             return 0;
275         }
276         if (s->dma_memory_read) {
277             s->dma_memory_read(s->dma_opaque, buf, dmalen);
278             dmalen = MIN(fifo8_num_free(&s->cmdfifo), dmalen);
279             fifo8_push_all(&s->cmdfifo, buf, dmalen);
280             esp_set_tc(s, esp_get_tc(s) - dmalen);
281         } else {
282             return 0;
283         }
284     } else {
285         dmalen = MIN(fifo8_num_used(&s->fifo), maxlen);
286         if (dmalen == 0) {
287             return 0;
288         }
289         n = esp_fifo_pop_buf(&s->fifo, buf, dmalen);
290         n = MIN(fifo8_num_free(&s->cmdfifo), n);
291         fifo8_push_all(&s->cmdfifo, buf, n);
292     }
293     trace_esp_get_cmd(dmalen, target);
294 
295     return dmalen;
296 }
297 
298 static void do_command_phase(ESPState *s)
299 {
300     uint32_t cmdlen;
301     int32_t datalen;
302     SCSIDevice *current_lun;
303     uint8_t buf[ESP_CMDFIFO_SZ];
304 
305     trace_esp_do_command_phase(s->lun);
306     cmdlen = fifo8_num_used(&s->cmdfifo);
307     if (!cmdlen || !s->current_dev) {
308         return;
309     }
310     esp_fifo_pop_buf(&s->cmdfifo, buf, cmdlen);
311 
312     current_lun = scsi_device_find(&s->bus, 0, s->current_dev->id, s->lun);
313     if (!current_lun) {
314         /* No such drive */
315         s->rregs[ESP_RSTAT] = 0;
316         s->rregs[ESP_RINTR] = INTR_DC;
317         s->rregs[ESP_RSEQ] = SEQ_0;
318         esp_raise_irq(s);
319         return;
320     }
321 
322     s->current_req = scsi_req_new(current_lun, 0, s->lun, buf, cmdlen, s);
323     datalen = scsi_req_enqueue(s->current_req);
324     s->ti_size = datalen;
325     fifo8_reset(&s->cmdfifo);
326     if (datalen != 0) {
327         s->ti_cmd = 0;
328         if (datalen > 0) {
329             /*
330              * Switch to DATA IN phase but wait until initial data xfer is
331              * complete before raising the command completion interrupt
332              */
333             s->data_in_ready = false;
334             esp_set_phase(s, STAT_DI);
335         } else {
336             esp_set_phase(s, STAT_DO);
337             s->rregs[ESP_RINTR] |= INTR_BS | INTR_FC;
338             esp_raise_irq(s);
339             esp_lower_drq(s);
340         }
341         scsi_req_continue(s->current_req);
342         return;
343     }
344 }
345 
346 static void do_message_phase(ESPState *s)
347 {
348     if (s->cmdfifo_cdb_offset) {
349         uint8_t message = esp_fifo_pop(&s->cmdfifo);
350 
351         trace_esp_do_identify(message);
352         s->lun = message & 7;
353         s->cmdfifo_cdb_offset--;
354     }
355 
356     /* Ignore extended messages for now */
357     if (s->cmdfifo_cdb_offset) {
358         int len = MIN(s->cmdfifo_cdb_offset, fifo8_num_used(&s->cmdfifo));
359         esp_fifo_pop_buf(&s->cmdfifo, NULL, len);
360         s->cmdfifo_cdb_offset = 0;
361     }
362 }
363 
364 static void do_cmd(ESPState *s)
365 {
366     do_message_phase(s);
367     assert(s->cmdfifo_cdb_offset == 0);
368     do_command_phase(s);
369 }
370 
371 static void satn_pdma_cb(ESPState *s)
372 {
373     uint8_t buf[ESP_FIFO_SZ];
374     int n;
375 
376     /* Copy FIFO into cmdfifo */
377     n = esp_fifo_pop_buf(&s->fifo, buf, fifo8_num_used(&s->fifo));
378     n = MIN(fifo8_num_free(&s->cmdfifo), n);
379     fifo8_push_all(&s->cmdfifo, buf, n);
380 
381     if (!esp_get_tc(s) && !fifo8_is_empty(&s->cmdfifo)) {
382         s->cmdfifo_cdb_offset = 1;
383         do_cmd(s);
384     }
385 }
386 
387 static void handle_satn(ESPState *s)
388 {
389     int32_t cmdlen;
390 
391     if (s->dma && !s->dma_enabled) {
392         s->dma_cb = handle_satn;
393         return;
394     }
395     esp_set_pdma_cb(s, SATN_PDMA_CB);
396     if (esp_select(s) < 0) {
397         return;
398     }
399     cmdlen = get_cmd(s, ESP_CMDFIFO_SZ);
400     if (cmdlen > 0) {
401         s->cmdfifo_cdb_offset = 1;
402         do_cmd(s);
403     } else if (cmdlen == 0) {
404         if (s->dma) {
405             esp_raise_drq(s);
406         }
407         /* Target present, but no cmd yet - switch to command phase */
408         s->rregs[ESP_RSEQ] = SEQ_CD;
409         esp_set_phase(s, STAT_CD);
410     }
411 }
412 
413 static void handle_s_without_atn(ESPState *s)
414 {
415     int32_t cmdlen;
416 
417     if (s->dma && !s->dma_enabled) {
418         s->dma_cb = handle_s_without_atn;
419         return;
420     }
421     esp_set_pdma_cb(s, DO_DMA_PDMA_CB);
422     if (esp_select(s) < 0) {
423         return;
424     }
425     cmdlen = get_cmd(s, ESP_CMDFIFO_SZ);
426     if (cmdlen > 0) {
427         s->cmdfifo_cdb_offset = 0;
428         do_cmd(s);
429     } else if (cmdlen == 0) {
430         if (s->dma) {
431             esp_raise_drq(s);
432         }
433         /* Target present, but no cmd yet - switch to command phase */
434         s->rregs[ESP_RSEQ] = SEQ_CD;
435         esp_set_phase(s, STAT_CD);
436     }
437 }
438 
439 static void satn_stop_pdma_cb(ESPState *s)
440 {
441     uint8_t buf[ESP_FIFO_SZ];
442     int n;
443 
444     /* Copy FIFO into cmdfifo */
445     n = esp_fifo_pop_buf(&s->fifo, buf, fifo8_num_used(&s->fifo));
446     n = MIN(fifo8_num_free(&s->cmdfifo), n);
447     fifo8_push_all(&s->cmdfifo, buf, n);
448 
449     if (!esp_get_tc(s) && !fifo8_is_empty(&s->cmdfifo)) {
450         trace_esp_handle_satn_stop(fifo8_num_used(&s->cmdfifo));
451         s->cmdfifo_cdb_offset = 1;
452         esp_set_phase(s, STAT_CD);
453         s->rregs[ESP_RSTAT] |= STAT_TC;
454         s->rregs[ESP_RINTR] |= INTR_BS | INTR_FC;
455         s->rregs[ESP_RSEQ] = SEQ_CD;
456         esp_raise_irq(s);
457     }
458 }
459 
460 static void handle_satn_stop(ESPState *s)
461 {
462     int32_t cmdlen;
463 
464     if (s->dma && !s->dma_enabled) {
465         s->dma_cb = handle_satn_stop;
466         return;
467     }
468     esp_set_pdma_cb(s, SATN_STOP_PDMA_CB);
469     if (esp_select(s) < 0) {
470         return;
471     }
472     cmdlen = get_cmd(s, 1);
473     if (cmdlen > 0) {
474         trace_esp_handle_satn_stop(fifo8_num_used(&s->cmdfifo));
475         s->cmdfifo_cdb_offset = 1;
476         esp_set_phase(s, STAT_MO);
477         s->rregs[ESP_RINTR] |= INTR_BS | INTR_FC;
478         s->rregs[ESP_RSEQ] = SEQ_MO;
479         esp_raise_irq(s);
480     } else if (cmdlen == 0) {
481         if (s->dma) {
482             esp_raise_drq(s);
483         }
484         /* Target present, switch to message out phase */
485         s->rregs[ESP_RSEQ] = SEQ_MO;
486         esp_set_phase(s, STAT_MO);
487     }
488 }
489 
490 static void write_response_pdma_cb(ESPState *s)
491 {
492     esp_set_phase(s, STAT_ST);
493     s->rregs[ESP_RINTR] |= INTR_BS | INTR_FC;
494     s->rregs[ESP_RSEQ] = SEQ_CD;
495     esp_raise_irq(s);
496 }
497 
498 static void write_response(ESPState *s)
499 {
500     uint8_t buf[2];
501 
502     trace_esp_write_response(s->status);
503 
504     buf[0] = s->status;
505     buf[1] = 0;
506 
507     if (s->dma) {
508         if (s->dma_memory_write) {
509             s->dma_memory_write(s->dma_opaque, buf, 2);
510             esp_set_phase(s, STAT_ST);
511             s->rregs[ESP_RINTR] |= INTR_BS | INTR_FC;
512             s->rregs[ESP_RSEQ] = SEQ_CD;
513         } else {
514             esp_set_pdma_cb(s, WRITE_RESPONSE_PDMA_CB);
515             esp_raise_drq(s);
516             return;
517         }
518     } else {
519         fifo8_reset(&s->fifo);
520         fifo8_push_all(&s->fifo, buf, 2);
521         s->rregs[ESP_RFLAGS] = 2;
522     }
523     esp_raise_irq(s);
524 }
525 
526 static void esp_dma_ti_check(ESPState *s)
527 {
528     if (esp_get_tc(s) == 0 && fifo8_num_used(&s->fifo) < 2) {
529         s->rregs[ESP_RINTR] |= INTR_BS;
530         esp_raise_irq(s);
531         esp_lower_drq(s);
532     }
533 }
534 
535 static void do_dma_pdma_cb(ESPState *s)
536 {
537     uint8_t buf[ESP_CMDFIFO_SZ];
538     int len;
539     uint32_t n;
540 
541     switch (esp_get_phase(s)) {
542     case STAT_MO:
543     case STAT_CD:
544         /* Copy FIFO into cmdfifo */
545         n = esp_fifo_pop_buf(&s->fifo, buf, fifo8_num_used(&s->fifo));
546         n = MIN(fifo8_num_free(&s->cmdfifo), n);
547         fifo8_push_all(&s->cmdfifo, buf, n);
548 
549         /* Ensure we have received complete command after SATN and stop */
550         if (esp_get_tc(s) || fifo8_is_empty(&s->cmdfifo)) {
551             return;
552         }
553 
554         s->ti_size = 0;
555         if (esp_get_phase(s) == STAT_CD) {
556             /* No command received */
557             if (s->cmdfifo_cdb_offset == fifo8_num_used(&s->cmdfifo)) {
558                 return;
559             }
560 
561             /* Command has been received */
562             do_cmd(s);
563         } else {
564             /*
565              * Extra message out bytes received: update cmdfifo_cdb_offset
566              * and then switch to command phase
567              */
568             s->cmdfifo_cdb_offset = fifo8_num_used(&s->cmdfifo);
569             esp_set_phase(s, STAT_CD);
570             s->rregs[ESP_RSEQ] = SEQ_CD;
571             s->rregs[ESP_RINTR] |= INTR_BS;
572             esp_raise_irq(s);
573         }
574         break;
575 
576     case STAT_DO:
577         if (!s->current_req) {
578             return;
579         }
580         /* Copy FIFO data to device */
581         len = MIN(s->async_len, ESP_FIFO_SZ);
582         len = MIN(len, fifo8_num_used(&s->fifo));
583         n = esp_fifo_pop_buf(&s->fifo, s->async_buf, len);
584         s->async_buf += n;
585         s->async_len -= n;
586         s->ti_size += n;
587 
588         if (s->async_len == 0 && fifo8_num_used(&s->fifo) < 2) {
589             /* Defer until the scsi layer has completed */
590             scsi_req_continue(s->current_req);
591             return;
592         }
593 
594         esp_dma_ti_check(s);
595         break;
596 
597     case STAT_DI:
598         if (!s->current_req) {
599             return;
600         }
601         /* Copy device data to FIFO */
602         len = MIN(s->async_len, esp_get_tc(s));
603         len = MIN(len, fifo8_num_free(&s->fifo));
604         fifo8_push_all(&s->fifo, s->async_buf, len);
605         s->async_buf += len;
606         s->async_len -= len;
607         s->ti_size -= len;
608         esp_set_tc(s, esp_get_tc(s) - len);
609 
610         if (s->async_len == 0 && fifo8_num_used(&s->fifo) < 2) {
611             /* Defer until the scsi layer has completed */
612             scsi_req_continue(s->current_req);
613             s->data_in_ready = false;
614             return;
615         }
616 
617         esp_dma_ti_check(s);
618         break;
619     }
620 }
621 
622 static void esp_do_dma(ESPState *s)
623 {
624     uint32_t len, cmdlen;
625     uint8_t buf[ESP_CMDFIFO_SZ];
626     int n;
627 
628     len = esp_get_tc(s);
629 
630     switch (esp_get_phase(s)) {
631     case STAT_MO:
632     case STAT_CD:
633         cmdlen = fifo8_num_used(&s->cmdfifo);
634         trace_esp_do_dma(cmdlen, len);
635         if (s->dma_memory_read) {
636             len = MIN(len, fifo8_num_free(&s->cmdfifo));
637             s->dma_memory_read(s->dma_opaque, buf, len);
638             fifo8_push_all(&s->cmdfifo, buf, len);
639             esp_set_tc(s, esp_get_tc(s) - len);
640         } else {
641             n = esp_fifo_pop_buf(&s->fifo, buf, fifo8_num_used(&s->fifo));
642             n = MIN(fifo8_num_free(&s->cmdfifo), n);
643             fifo8_push_all(&s->cmdfifo, buf, n);
644             esp_set_tc(s, esp_get_tc(s) - n);
645 
646             esp_set_pdma_cb(s, DO_DMA_PDMA_CB);
647             esp_raise_drq(s);
648 
649             /* Ensure we have received complete command after SATN and stop */
650             if (esp_get_tc(s) || fifo8_is_empty(&s->cmdfifo)) {
651                 return;
652             }
653         }
654         trace_esp_handle_ti_cmd(cmdlen);
655         s->ti_size = 0;
656         if (esp_get_phase(s) == STAT_CD) {
657             /* No command received */
658             if (s->cmdfifo_cdb_offset == fifo8_num_used(&s->cmdfifo)) {
659                 return;
660             }
661 
662             /* Command has been received */
663             do_cmd(s);
664         } else {
665             /*
666              * Extra message out bytes received: update cmdfifo_cdb_offset
667              * and then switch to command phase
668              */
669             s->cmdfifo_cdb_offset = fifo8_num_used(&s->cmdfifo);
670             esp_set_phase(s, STAT_CD);
671             s->rregs[ESP_RSEQ] = SEQ_CD;
672             s->rregs[ESP_RINTR] |= INTR_BS;
673             esp_raise_irq(s);
674         }
675         break;
676 
677     case STAT_DO:
678         if (!s->current_req) {
679             return;
680         }
681         if (s->async_len == 0 && esp_get_tc(s) && s->ti_size) {
682             /* Defer until data is available.  */
683             return;
684         }
685         if (len > s->async_len) {
686             len = s->async_len;
687         }
688         if (s->dma_memory_read) {
689             s->dma_memory_read(s->dma_opaque, s->async_buf, len);
690 
691             esp_set_tc(s, esp_get_tc(s) - len);
692             s->async_buf += len;
693             s->async_len -= len;
694             s->ti_size += len;
695 
696             if (s->async_len == 0 && fifo8_num_used(&s->fifo) < 2) {
697                 /* Defer until the scsi layer has completed */
698                 scsi_req_continue(s->current_req);
699                 return;
700             }
701 
702             esp_dma_ti_check(s);
703         } else {
704             /* Copy FIFO data to device */
705             len = MIN(s->async_len, ESP_FIFO_SZ);
706             len = MIN(len, fifo8_num_used(&s->fifo));
707             n = esp_fifo_pop_buf(&s->fifo, s->async_buf, len);
708             s->async_buf += n;
709             s->async_len -= n;
710             s->ti_size += n;
711 
712             esp_set_pdma_cb(s, DO_DMA_PDMA_CB);
713             esp_raise_drq(s);
714 
715             if (s->async_len == 0 && fifo8_num_used(&s->fifo) < 2) {
716                 /* Defer until the scsi layer has completed */
717                 scsi_req_continue(s->current_req);
718                 return;
719             }
720 
721             esp_dma_ti_check(s);
722         }
723         break;
724 
725     case STAT_DI:
726         if (!s->current_req) {
727             return;
728         }
729         if (s->async_len == 0 && esp_get_tc(s) && s->ti_size) {
730             /* Defer until data is available.  */
731             return;
732         }
733         if (len > s->async_len) {
734             len = s->async_len;
735         }
736         if (s->dma_memory_write) {
737             s->dma_memory_write(s->dma_opaque, s->async_buf, len);
738 
739             esp_set_tc(s, esp_get_tc(s) - len);
740             s->async_buf += len;
741             s->async_len -= len;
742             s->ti_size -= len;
743 
744             if (s->async_len == 0 && fifo8_num_used(&s->fifo) < 2) {
745                 /* Defer until the scsi layer has completed */
746                 scsi_req_continue(s->current_req);
747                 return;
748             }
749 
750             esp_dma_ti_check(s);
751         } else {
752             /* Copy device data to FIFO */
753             len = MIN(len, fifo8_num_free(&s->fifo));
754             fifo8_push_all(&s->fifo, s->async_buf, len);
755             s->async_buf += len;
756             s->async_len -= len;
757             s->ti_size -= len;
758             esp_set_tc(s, esp_get_tc(s) - len);
759             esp_set_pdma_cb(s, DO_DMA_PDMA_CB);
760             esp_raise_drq(s);
761 
762             if (s->async_len == 0 && fifo8_num_used(&s->fifo) < 2) {
763                 /* Defer until the scsi layer has completed */
764                 scsi_req_continue(s->current_req);
765                 return;
766             }
767 
768             esp_dma_ti_check(s);
769         }
770         break;
771     }
772 }
773 
774 static void esp_do_nodma(ESPState *s)
775 {
776     uint8_t buf[ESP_FIFO_SZ];
777     uint32_t cmdlen;
778     int len, n;
779 
780     switch (esp_get_phase(s)) {
781     case STAT_MO:
782     case STAT_CD:
783         /* Copy FIFO into cmdfifo */
784         n = esp_fifo_pop_buf(&s->fifo, buf, fifo8_num_used(&s->fifo));
785         n = MIN(fifo8_num_free(&s->cmdfifo), n);
786         fifo8_push_all(&s->cmdfifo, buf, n);
787 
788         cmdlen = fifo8_num_used(&s->cmdfifo);
789         trace_esp_handle_ti_cmd(cmdlen);
790         s->ti_size = 0;
791         if (esp_get_phase(s) == STAT_CD) {
792             /* No command received */
793             if (s->cmdfifo_cdb_offset == fifo8_num_used(&s->cmdfifo)) {
794                 return;
795             }
796 
797             /* Command has been received */
798             do_cmd(s);
799         } else {
800             /*
801              * Extra message out bytes received: update cmdfifo_cdb_offset
802              * and then switch to command phase
803              */
804             s->cmdfifo_cdb_offset = fifo8_num_used(&s->cmdfifo);
805             esp_set_phase(s, STAT_CD);
806             s->rregs[ESP_RSEQ] = SEQ_CD;
807             s->rregs[ESP_RINTR] |= INTR_BS;
808             esp_raise_irq(s);
809         }
810         break;
811 
812     case STAT_DO:
813         if (!s->current_req) {
814             return;
815         }
816         if (s->async_len == 0) {
817             /* Defer until data is available.  */
818             return;
819         }
820         len = MIN(s->async_len, ESP_FIFO_SZ);
821         len = MIN(len, fifo8_num_used(&s->fifo));
822         esp_fifo_pop_buf(&s->fifo, s->async_buf, len);
823         s->async_buf += len;
824         s->async_len -= len;
825         s->ti_size += len;
826 
827         if (s->async_len == 0) {
828             scsi_req_continue(s->current_req);
829             return;
830         }
831 
832         s->rregs[ESP_RINTR] |= INTR_BS;
833         esp_raise_irq(s);
834         break;
835 
836     case STAT_DI:
837         if (!s->current_req) {
838             return;
839         }
840         if (s->async_len == 0) {
841             /* Defer until data is available.  */
842             return;
843         }
844         if (fifo8_is_empty(&s->fifo)) {
845             fifo8_push(&s->fifo, s->async_buf[0]);
846             s->async_buf++;
847             s->async_len--;
848             s->ti_size--;
849         }
850 
851         if (s->async_len == 0) {
852             scsi_req_continue(s->current_req);
853             return;
854         }
855 
856         s->rregs[ESP_RINTR] |= INTR_BS;
857         esp_raise_irq(s);
858         break;
859     }
860 }
861 
862 static void esp_pdma_cb(ESPState *s)
863 {
864     switch (s->pdma_cb) {
865     case SATN_PDMA_CB:
866         satn_pdma_cb(s);
867         break;
868     case SATN_STOP_PDMA_CB:
869         satn_stop_pdma_cb(s);
870         break;
871     case WRITE_RESPONSE_PDMA_CB:
872         write_response_pdma_cb(s);
873         break;
874     case DO_DMA_PDMA_CB:
875         do_dma_pdma_cb(s);
876         break;
877     default:
878         g_assert_not_reached();
879     }
880 }
881 
882 void esp_command_complete(SCSIRequest *req, size_t resid)
883 {
884     ESPState *s = req->hba_private;
885     int to_device = (esp_get_phase(s) == STAT_DO);
886 
887     trace_esp_command_complete();
888 
889     /*
890      * Non-DMA transfers from the target will leave the last byte in
891      * the FIFO so don't reset ti_size in this case
892      */
893     if (s->dma || to_device) {
894         if (s->ti_size != 0) {
895             trace_esp_command_complete_unexpected();
896         }
897     }
898 
899     s->async_len = 0;
900     if (req->status) {
901         trace_esp_command_complete_fail();
902     }
903     s->status = req->status;
904 
905     /*
906      * Switch to status phase. For non-DMA transfers from the target the last
907      * byte is still in the FIFO
908      */
909     esp_set_phase(s, STAT_ST);
910     if (s->ti_size == 0) {
911         /*
912          * Transfer complete: force TC to zero just in case a TI command was
913          * requested for more data than the command returns (Solaris 8 does
914          * this)
915          */
916         esp_set_tc(s, 0);
917         esp_dma_ti_check(s);
918     } else {
919         /*
920          * Transfer truncated: raise INTR_BS to indicate early change of
921          * phase
922          */
923         s->rregs[ESP_RINTR] |= INTR_BS;
924         esp_raise_irq(s);
925         s->ti_size = 0;
926     }
927 
928     if (s->current_req) {
929         scsi_req_unref(s->current_req);
930         s->current_req = NULL;
931         s->current_dev = NULL;
932     }
933 }
934 
935 void esp_transfer_data(SCSIRequest *req, uint32_t len)
936 {
937     ESPState *s = req->hba_private;
938     int to_device = (esp_get_phase(s) == STAT_DO);
939     uint32_t dmalen = esp_get_tc(s);
940 
941     trace_esp_transfer_data(dmalen, s->ti_size);
942     s->async_len = len;
943     s->async_buf = scsi_req_get_buf(req);
944 
945     if (!to_device && !s->data_in_ready) {
946         /*
947          * Initial incoming data xfer is complete so raise command
948          * completion interrupt
949          */
950         s->data_in_ready = true;
951         s->rregs[ESP_RINTR] |= INTR_BS;
952         esp_raise_irq(s);
953     }
954 
955     /*
956      * Always perform the initial transfer upon reception of the next TI
957      * command to ensure the DMA/non-DMA status of the command is correct.
958      * It is not possible to use s->dma directly in the section below as
959      * some OSs send non-DMA NOP commands after a DMA transfer. Hence if the
960      * async data transfer is delayed then s->dma is set incorrectly.
961      */
962 
963     if (s->ti_cmd == (CMD_TI | CMD_DMA)) {
964         /* When the SCSI layer returns more data, raise deferred INTR_BS */
965         esp_dma_ti_check(s);
966 
967         esp_do_dma(s);
968     } else if (s->ti_cmd == CMD_TI) {
969         esp_do_nodma(s);
970     }
971 }
972 
973 static void handle_ti(ESPState *s)
974 {
975     uint32_t dmalen;
976 
977     if (s->dma && !s->dma_enabled) {
978         s->dma_cb = handle_ti;
979         return;
980     }
981 
982     s->ti_cmd = s->rregs[ESP_CMD];
983     if (s->dma) {
984         dmalen = esp_get_tc(s);
985         trace_esp_handle_ti(dmalen);
986         esp_do_dma(s);
987     } else {
988         trace_esp_handle_ti(s->ti_size);
989         esp_do_nodma(s);
990     }
991 }
992 
993 void esp_hard_reset(ESPState *s)
994 {
995     memset(s->rregs, 0, ESP_REGS);
996     memset(s->wregs, 0, ESP_REGS);
997     s->tchi_written = 0;
998     s->ti_size = 0;
999     s->async_len = 0;
1000     fifo8_reset(&s->fifo);
1001     fifo8_reset(&s->cmdfifo);
1002     s->dma = 0;
1003     s->dma_cb = NULL;
1004 
1005     s->rregs[ESP_CFG1] = 7;
1006 }
1007 
1008 static void esp_soft_reset(ESPState *s)
1009 {
1010     qemu_irq_lower(s->irq);
1011     qemu_irq_lower(s->irq_data);
1012     esp_hard_reset(s);
1013 }
1014 
1015 static void esp_bus_reset(ESPState *s)
1016 {
1017     bus_cold_reset(BUS(&s->bus));
1018 }
1019 
1020 static void parent_esp_reset(ESPState *s, int irq, int level)
1021 {
1022     if (level) {
1023         esp_soft_reset(s);
1024     }
1025 }
1026 
1027 static void esp_run_cmd(ESPState *s)
1028 {
1029     uint8_t cmd = s->rregs[ESP_CMD];
1030 
1031     if (cmd & CMD_DMA) {
1032         s->dma = 1;
1033         /* Reload DMA counter.  */
1034         if (esp_get_stc(s) == 0) {
1035             esp_set_tc(s, 0x10000);
1036         } else {
1037             esp_set_tc(s, esp_get_stc(s));
1038         }
1039     } else {
1040         s->dma = 0;
1041     }
1042     switch (cmd & CMD_CMD) {
1043     case CMD_NOP:
1044         trace_esp_mem_writeb_cmd_nop(cmd);
1045         break;
1046     case CMD_FLUSH:
1047         trace_esp_mem_writeb_cmd_flush(cmd);
1048         fifo8_reset(&s->fifo);
1049         break;
1050     case CMD_RESET:
1051         trace_esp_mem_writeb_cmd_reset(cmd);
1052         esp_soft_reset(s);
1053         break;
1054     case CMD_BUSRESET:
1055         trace_esp_mem_writeb_cmd_bus_reset(cmd);
1056         esp_bus_reset(s);
1057         if (!(s->wregs[ESP_CFG1] & CFG1_RESREPT)) {
1058             s->rregs[ESP_RINTR] |= INTR_RST;
1059             esp_raise_irq(s);
1060         }
1061         break;
1062     case CMD_TI:
1063         trace_esp_mem_writeb_cmd_ti(cmd);
1064         handle_ti(s);
1065         break;
1066     case CMD_ICCS:
1067         trace_esp_mem_writeb_cmd_iccs(cmd);
1068         write_response(s);
1069         s->rregs[ESP_RINTR] |= INTR_FC;
1070         esp_set_phase(s, STAT_MI);
1071         break;
1072     case CMD_MSGACC:
1073         trace_esp_mem_writeb_cmd_msgacc(cmd);
1074         s->rregs[ESP_RINTR] |= INTR_DC;
1075         s->rregs[ESP_RSEQ] = 0;
1076         s->rregs[ESP_RFLAGS] = 0;
1077         esp_raise_irq(s);
1078         break;
1079     case CMD_PAD:
1080         trace_esp_mem_writeb_cmd_pad(cmd);
1081         s->rregs[ESP_RSTAT] = STAT_TC;
1082         s->rregs[ESP_RINTR] |= INTR_FC;
1083         s->rregs[ESP_RSEQ] = 0;
1084         break;
1085     case CMD_SATN:
1086         trace_esp_mem_writeb_cmd_satn(cmd);
1087         break;
1088     case CMD_RSTATN:
1089         trace_esp_mem_writeb_cmd_rstatn(cmd);
1090         break;
1091     case CMD_SEL:
1092         trace_esp_mem_writeb_cmd_sel(cmd);
1093         handle_s_without_atn(s);
1094         break;
1095     case CMD_SELATN:
1096         trace_esp_mem_writeb_cmd_selatn(cmd);
1097         handle_satn(s);
1098         break;
1099     case CMD_SELATNS:
1100         trace_esp_mem_writeb_cmd_selatns(cmd);
1101         handle_satn_stop(s);
1102         break;
1103     case CMD_ENSEL:
1104         trace_esp_mem_writeb_cmd_ensel(cmd);
1105         s->rregs[ESP_RINTR] = 0;
1106         break;
1107     case CMD_DISSEL:
1108         trace_esp_mem_writeb_cmd_dissel(cmd);
1109         s->rregs[ESP_RINTR] = 0;
1110         esp_raise_irq(s);
1111         break;
1112     default:
1113         trace_esp_error_unhandled_command(cmd);
1114         break;
1115     }
1116 }
1117 
1118 uint64_t esp_reg_read(ESPState *s, uint32_t saddr)
1119 {
1120     uint32_t val;
1121 
1122     switch (saddr) {
1123     case ESP_FIFO:
1124         if (s->dma_memory_read && s->dma_memory_write &&
1125                 (s->rregs[ESP_RSTAT] & STAT_PIO_MASK) == 0) {
1126             /* Data out.  */
1127             qemu_log_mask(LOG_UNIMP, "esp: PIO data read not implemented\n");
1128             s->rregs[ESP_FIFO] = 0;
1129         } else {
1130             if (esp_get_phase(s) == STAT_DI) {
1131                 if (s->ti_size) {
1132                     esp_do_nodma(s);
1133                 } else {
1134                     /*
1135                      * The last byte of a non-DMA transfer has been read out
1136                      * of the FIFO so switch to status phase
1137                      */
1138                     esp_set_phase(s, STAT_ST);
1139                 }
1140             }
1141             s->rregs[ESP_FIFO] = esp_fifo_pop(&s->fifo);
1142         }
1143         val = s->rregs[ESP_FIFO];
1144         break;
1145     case ESP_RINTR:
1146         /*
1147          * Clear sequence step, interrupt register and all status bits
1148          * except TC
1149          */
1150         val = s->rregs[ESP_RINTR];
1151         s->rregs[ESP_RINTR] = 0;
1152         s->rregs[ESP_RSTAT] &= ~STAT_TC;
1153         /*
1154          * According to the datasheet ESP_RSEQ should be cleared, but as the
1155          * emulation currently defers information transfers to the next TI
1156          * command leave it for now so that pedantic guests such as the old
1157          * Linux 2.6 driver see the correct flags before the next SCSI phase
1158          * transition.
1159          *
1160          * s->rregs[ESP_RSEQ] = SEQ_0;
1161          */
1162         esp_lower_irq(s);
1163         break;
1164     case ESP_TCHI:
1165         /* Return the unique id if the value has never been written */
1166         if (!s->tchi_written) {
1167             val = s->chip_id;
1168         } else {
1169             val = s->rregs[saddr];
1170         }
1171         break;
1172      case ESP_RFLAGS:
1173         /* Bottom 5 bits indicate number of bytes in FIFO */
1174         val = fifo8_num_used(&s->fifo);
1175         break;
1176     default:
1177         val = s->rregs[saddr];
1178         break;
1179     }
1180 
1181     trace_esp_mem_readb(saddr, val);
1182     return val;
1183 }
1184 
1185 void esp_reg_write(ESPState *s, uint32_t saddr, uint64_t val)
1186 {
1187     trace_esp_mem_writeb(saddr, s->wregs[saddr], val);
1188     switch (saddr) {
1189     case ESP_TCHI:
1190         s->tchi_written = true;
1191         /* fall through */
1192     case ESP_TCLO:
1193     case ESP_TCMID:
1194         s->rregs[ESP_RSTAT] &= ~STAT_TC;
1195         break;
1196     case ESP_FIFO:
1197         if (esp_get_phase(s) == STAT_MO || esp_get_phase(s) == STAT_CD) {
1198             if (!fifo8_is_full(&s->fifo)) {
1199                 esp_fifo_push(&s->fifo, val);
1200                 esp_fifo_push(&s->cmdfifo, fifo8_pop(&s->fifo));
1201             }
1202 
1203             /*
1204              * If any unexpected message out/command phase data is
1205              * transferred using non-DMA, raise the interrupt
1206              */
1207             if (s->rregs[ESP_CMD] == CMD_TI) {
1208                 s->rregs[ESP_RINTR] |= INTR_BS;
1209                 esp_raise_irq(s);
1210             }
1211         } else {
1212             esp_fifo_push(&s->fifo, val);
1213         }
1214         break;
1215     case ESP_CMD:
1216         s->rregs[saddr] = val;
1217         esp_run_cmd(s);
1218         break;
1219     case ESP_WBUSID ... ESP_WSYNO:
1220         break;
1221     case ESP_CFG1:
1222     case ESP_CFG2: case ESP_CFG3:
1223     case ESP_RES3: case ESP_RES4:
1224         s->rregs[saddr] = val;
1225         break;
1226     case ESP_WCCF ... ESP_WTEST:
1227         break;
1228     default:
1229         trace_esp_error_invalid_write(val, saddr);
1230         return;
1231     }
1232     s->wregs[saddr] = val;
1233 }
1234 
1235 static bool esp_mem_accepts(void *opaque, hwaddr addr,
1236                             unsigned size, bool is_write,
1237                             MemTxAttrs attrs)
1238 {
1239     return (size == 1) || (is_write && size == 4);
1240 }
1241 
1242 static bool esp_is_before_version_5(void *opaque, int version_id)
1243 {
1244     ESPState *s = ESP(opaque);
1245 
1246     version_id = MIN(version_id, s->mig_version_id);
1247     return version_id < 5;
1248 }
1249 
1250 static bool esp_is_version_5(void *opaque, int version_id)
1251 {
1252     ESPState *s = ESP(opaque);
1253 
1254     version_id = MIN(version_id, s->mig_version_id);
1255     return version_id >= 5;
1256 }
1257 
1258 static bool esp_is_version_6(void *opaque, int version_id)
1259 {
1260     ESPState *s = ESP(opaque);
1261 
1262     version_id = MIN(version_id, s->mig_version_id);
1263     return version_id >= 6;
1264 }
1265 
1266 int esp_pre_save(void *opaque)
1267 {
1268     ESPState *s = ESP(object_resolve_path_component(
1269                       OBJECT(opaque), "esp"));
1270 
1271     s->mig_version_id = vmstate_esp.version_id;
1272     return 0;
1273 }
1274 
1275 static int esp_post_load(void *opaque, int version_id)
1276 {
1277     ESPState *s = ESP(opaque);
1278     int len, i;
1279 
1280     version_id = MIN(version_id, s->mig_version_id);
1281 
1282     if (version_id < 5) {
1283         esp_set_tc(s, s->mig_dma_left);
1284 
1285         /* Migrate ti_buf to fifo */
1286         len = s->mig_ti_wptr - s->mig_ti_rptr;
1287         for (i = 0; i < len; i++) {
1288             fifo8_push(&s->fifo, s->mig_ti_buf[i]);
1289         }
1290 
1291         /* Migrate cmdbuf to cmdfifo */
1292         for (i = 0; i < s->mig_cmdlen; i++) {
1293             fifo8_push(&s->cmdfifo, s->mig_cmdbuf[i]);
1294         }
1295     }
1296 
1297     s->mig_version_id = vmstate_esp.version_id;
1298     return 0;
1299 }
1300 
1301 /*
1302  * PDMA (or pseudo-DMA) is only used on the Macintosh and requires the
1303  * guest CPU to perform the transfers between the SCSI bus and memory
1304  * itself. This is indicated by the dma_memory_read and dma_memory_write
1305  * functions being NULL (in contrast to the ESP PCI device) whilst
1306  * dma_enabled is still set.
1307  */
1308 
1309 static bool esp_pdma_needed(void *opaque)
1310 {
1311     ESPState *s = ESP(opaque);
1312 
1313     return s->dma_memory_read == NULL && s->dma_memory_write == NULL &&
1314            s->dma_enabled;
1315 }
1316 
1317 static const VMStateDescription vmstate_esp_pdma = {
1318     .name = "esp/pdma",
1319     .version_id = 0,
1320     .minimum_version_id = 0,
1321     .needed = esp_pdma_needed,
1322     .fields = (const VMStateField[]) {
1323         VMSTATE_UINT8(pdma_cb, ESPState),
1324         VMSTATE_END_OF_LIST()
1325     }
1326 };
1327 
1328 const VMStateDescription vmstate_esp = {
1329     .name = "esp",
1330     .version_id = 6,
1331     .minimum_version_id = 3,
1332     .post_load = esp_post_load,
1333     .fields = (const VMStateField[]) {
1334         VMSTATE_BUFFER(rregs, ESPState),
1335         VMSTATE_BUFFER(wregs, ESPState),
1336         VMSTATE_INT32(ti_size, ESPState),
1337         VMSTATE_UINT32_TEST(mig_ti_rptr, ESPState, esp_is_before_version_5),
1338         VMSTATE_UINT32_TEST(mig_ti_wptr, ESPState, esp_is_before_version_5),
1339         VMSTATE_BUFFER_TEST(mig_ti_buf, ESPState, esp_is_before_version_5),
1340         VMSTATE_UINT32(status, ESPState),
1341         VMSTATE_UINT32_TEST(mig_deferred_status, ESPState,
1342                             esp_is_before_version_5),
1343         VMSTATE_BOOL_TEST(mig_deferred_complete, ESPState,
1344                           esp_is_before_version_5),
1345         VMSTATE_UINT32(dma, ESPState),
1346         VMSTATE_STATIC_BUFFER(mig_cmdbuf, ESPState, 0,
1347                               esp_is_before_version_5, 0, 16),
1348         VMSTATE_STATIC_BUFFER(mig_cmdbuf, ESPState, 4,
1349                               esp_is_before_version_5, 16,
1350                               sizeof(typeof_field(ESPState, mig_cmdbuf))),
1351         VMSTATE_UINT32_TEST(mig_cmdlen, ESPState, esp_is_before_version_5),
1352         VMSTATE_UINT32(do_cmd, ESPState),
1353         VMSTATE_UINT32_TEST(mig_dma_left, ESPState, esp_is_before_version_5),
1354         VMSTATE_BOOL_TEST(data_in_ready, ESPState, esp_is_version_5),
1355         VMSTATE_UINT8_TEST(cmdfifo_cdb_offset, ESPState, esp_is_version_5),
1356         VMSTATE_FIFO8_TEST(fifo, ESPState, esp_is_version_5),
1357         VMSTATE_FIFO8_TEST(cmdfifo, ESPState, esp_is_version_5),
1358         VMSTATE_UINT8_TEST(ti_cmd, ESPState, esp_is_version_5),
1359         VMSTATE_UINT8_TEST(lun, ESPState, esp_is_version_6),
1360         VMSTATE_END_OF_LIST()
1361     },
1362     .subsections = (const VMStateDescription * const []) {
1363         &vmstate_esp_pdma,
1364         NULL
1365     }
1366 };
1367 
1368 static void sysbus_esp_mem_write(void *opaque, hwaddr addr,
1369                                  uint64_t val, unsigned int size)
1370 {
1371     SysBusESPState *sysbus = opaque;
1372     ESPState *s = ESP(&sysbus->esp);
1373     uint32_t saddr;
1374 
1375     saddr = addr >> sysbus->it_shift;
1376     esp_reg_write(s, saddr, val);
1377 }
1378 
1379 static uint64_t sysbus_esp_mem_read(void *opaque, hwaddr addr,
1380                                     unsigned int size)
1381 {
1382     SysBusESPState *sysbus = opaque;
1383     ESPState *s = ESP(&sysbus->esp);
1384     uint32_t saddr;
1385 
1386     saddr = addr >> sysbus->it_shift;
1387     return esp_reg_read(s, saddr);
1388 }
1389 
1390 static const MemoryRegionOps sysbus_esp_mem_ops = {
1391     .read = sysbus_esp_mem_read,
1392     .write = sysbus_esp_mem_write,
1393     .endianness = DEVICE_NATIVE_ENDIAN,
1394     .valid.accepts = esp_mem_accepts,
1395 };
1396 
1397 static void sysbus_esp_pdma_write(void *opaque, hwaddr addr,
1398                                   uint64_t val, unsigned int size)
1399 {
1400     SysBusESPState *sysbus = opaque;
1401     ESPState *s = ESP(&sysbus->esp);
1402 
1403     trace_esp_pdma_write(size);
1404 
1405     switch (size) {
1406     case 1:
1407         esp_pdma_write(s, val);
1408         break;
1409     case 2:
1410         esp_pdma_write(s, val >> 8);
1411         esp_pdma_write(s, val);
1412         break;
1413     }
1414     esp_pdma_cb(s);
1415 }
1416 
1417 static uint64_t sysbus_esp_pdma_read(void *opaque, hwaddr addr,
1418                                      unsigned int size)
1419 {
1420     SysBusESPState *sysbus = opaque;
1421     ESPState *s = ESP(&sysbus->esp);
1422     uint64_t val = 0;
1423 
1424     trace_esp_pdma_read(size);
1425 
1426     switch (size) {
1427     case 1:
1428         val = esp_pdma_read(s);
1429         break;
1430     case 2:
1431         val = esp_pdma_read(s);
1432         val = (val << 8) | esp_pdma_read(s);
1433         break;
1434     }
1435     esp_pdma_cb(s);
1436     return val;
1437 }
1438 
1439 static void *esp_load_request(QEMUFile *f, SCSIRequest *req)
1440 {
1441     ESPState *s = container_of(req->bus, ESPState, bus);
1442 
1443     scsi_req_ref(req);
1444     s->current_req = req;
1445     return s;
1446 }
1447 
1448 static const MemoryRegionOps sysbus_esp_pdma_ops = {
1449     .read = sysbus_esp_pdma_read,
1450     .write = sysbus_esp_pdma_write,
1451     .endianness = DEVICE_NATIVE_ENDIAN,
1452     .valid.min_access_size = 1,
1453     .valid.max_access_size = 4,
1454     .impl.min_access_size = 1,
1455     .impl.max_access_size = 2,
1456 };
1457 
1458 static const struct SCSIBusInfo esp_scsi_info = {
1459     .tcq = false,
1460     .max_target = ESP_MAX_DEVS,
1461     .max_lun = 7,
1462 
1463     .load_request = esp_load_request,
1464     .transfer_data = esp_transfer_data,
1465     .complete = esp_command_complete,
1466     .cancel = esp_request_cancelled
1467 };
1468 
1469 static void sysbus_esp_gpio_demux(void *opaque, int irq, int level)
1470 {
1471     SysBusESPState *sysbus = SYSBUS_ESP(opaque);
1472     ESPState *s = ESP(&sysbus->esp);
1473 
1474     switch (irq) {
1475     case 0:
1476         parent_esp_reset(s, irq, level);
1477         break;
1478     case 1:
1479         esp_dma_enable(s, irq, level);
1480         break;
1481     }
1482 }
1483 
1484 static void sysbus_esp_realize(DeviceState *dev, Error **errp)
1485 {
1486     SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
1487     SysBusESPState *sysbus = SYSBUS_ESP(dev);
1488     ESPState *s = ESP(&sysbus->esp);
1489 
1490     if (!qdev_realize(DEVICE(s), NULL, errp)) {
1491         return;
1492     }
1493 
1494     sysbus_init_irq(sbd, &s->irq);
1495     sysbus_init_irq(sbd, &s->irq_data);
1496     assert(sysbus->it_shift != -1);
1497 
1498     s->chip_id = TCHI_FAS100A;
1499     memory_region_init_io(&sysbus->iomem, OBJECT(sysbus), &sysbus_esp_mem_ops,
1500                           sysbus, "esp-regs", ESP_REGS << sysbus->it_shift);
1501     sysbus_init_mmio(sbd, &sysbus->iomem);
1502     memory_region_init_io(&sysbus->pdma, OBJECT(sysbus), &sysbus_esp_pdma_ops,
1503                           sysbus, "esp-pdma", 4);
1504     sysbus_init_mmio(sbd, &sysbus->pdma);
1505 
1506     qdev_init_gpio_in(dev, sysbus_esp_gpio_demux, 2);
1507 
1508     scsi_bus_init(&s->bus, sizeof(s->bus), dev, &esp_scsi_info);
1509 }
1510 
1511 static void sysbus_esp_hard_reset(DeviceState *dev)
1512 {
1513     SysBusESPState *sysbus = SYSBUS_ESP(dev);
1514     ESPState *s = ESP(&sysbus->esp);
1515 
1516     esp_hard_reset(s);
1517 }
1518 
1519 static void sysbus_esp_init(Object *obj)
1520 {
1521     SysBusESPState *sysbus = SYSBUS_ESP(obj);
1522 
1523     object_initialize_child(obj, "esp", &sysbus->esp, TYPE_ESP);
1524 }
1525 
1526 static const VMStateDescription vmstate_sysbus_esp_scsi = {
1527     .name = "sysbusespscsi",
1528     .version_id = 2,
1529     .minimum_version_id = 1,
1530     .pre_save = esp_pre_save,
1531     .fields = (const VMStateField[]) {
1532         VMSTATE_UINT8_V(esp.mig_version_id, SysBusESPState, 2),
1533         VMSTATE_STRUCT(esp, SysBusESPState, 0, vmstate_esp, ESPState),
1534         VMSTATE_END_OF_LIST()
1535     }
1536 };
1537 
1538 static void sysbus_esp_class_init(ObjectClass *klass, void *data)
1539 {
1540     DeviceClass *dc = DEVICE_CLASS(klass);
1541 
1542     dc->realize = sysbus_esp_realize;
1543     dc->reset = sysbus_esp_hard_reset;
1544     dc->vmsd = &vmstate_sysbus_esp_scsi;
1545     set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
1546 }
1547 
1548 static const TypeInfo sysbus_esp_info = {
1549     .name          = TYPE_SYSBUS_ESP,
1550     .parent        = TYPE_SYS_BUS_DEVICE,
1551     .instance_init = sysbus_esp_init,
1552     .instance_size = sizeof(SysBusESPState),
1553     .class_init    = sysbus_esp_class_init,
1554 };
1555 
1556 static void esp_finalize(Object *obj)
1557 {
1558     ESPState *s = ESP(obj);
1559 
1560     fifo8_destroy(&s->fifo);
1561     fifo8_destroy(&s->cmdfifo);
1562 }
1563 
1564 static void esp_init(Object *obj)
1565 {
1566     ESPState *s = ESP(obj);
1567 
1568     fifo8_create(&s->fifo, ESP_FIFO_SZ);
1569     fifo8_create(&s->cmdfifo, ESP_CMDFIFO_SZ);
1570 }
1571 
1572 static void esp_class_init(ObjectClass *klass, void *data)
1573 {
1574     DeviceClass *dc = DEVICE_CLASS(klass);
1575 
1576     /* internal device for sysbusesp/pciespscsi, not user-creatable */
1577     dc->user_creatable = false;
1578     set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
1579 }
1580 
1581 static const TypeInfo esp_info = {
1582     .name = TYPE_ESP,
1583     .parent = TYPE_DEVICE,
1584     .instance_init = esp_init,
1585     .instance_finalize = esp_finalize,
1586     .instance_size = sizeof(ESPState),
1587     .class_init = esp_class_init,
1588 };
1589 
1590 static void esp_register_types(void)
1591 {
1592     type_register_static(&sysbus_esp_info);
1593     type_register_static(&esp_info);
1594 }
1595 
1596 type_init(esp_register_types)
1597