xref: /qemu/hw/scsi/esp.c (revision df91fd4ecdc777fbf6282f99656f74a9edab69db)
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         s->do_cmd = 0;
384         do_cmd(s);
385     }
386 }
387 
388 static void handle_satn(ESPState *s)
389 {
390     int32_t cmdlen;
391 
392     if (s->dma && !s->dma_enabled) {
393         s->dma_cb = handle_satn;
394         return;
395     }
396     esp_set_pdma_cb(s, SATN_PDMA_CB);
397     if (esp_select(s) < 0) {
398         return;
399     }
400     cmdlen = get_cmd(s, ESP_CMDFIFO_SZ);
401     if (cmdlen > 0) {
402         s->cmdfifo_cdb_offset = 1;
403         s->do_cmd = 0;
404         do_cmd(s);
405     } else if (cmdlen == 0) {
406         if (s->dma) {
407             esp_raise_drq(s);
408         }
409         s->do_cmd = 1;
410         /* Target present, but no cmd yet - switch to command phase */
411         s->rregs[ESP_RSEQ] = SEQ_CD;
412         esp_set_phase(s, STAT_CD);
413     }
414 }
415 
416 static void handle_s_without_atn(ESPState *s)
417 {
418     int32_t cmdlen;
419 
420     if (s->dma && !s->dma_enabled) {
421         s->dma_cb = handle_s_without_atn;
422         return;
423     }
424     esp_set_pdma_cb(s, DO_DMA_PDMA_CB);
425     if (esp_select(s) < 0) {
426         return;
427     }
428     cmdlen = get_cmd(s, ESP_CMDFIFO_SZ);
429     if (cmdlen > 0) {
430         s->cmdfifo_cdb_offset = 0;
431         s->do_cmd = 0;
432         do_cmd(s);
433     } else if (cmdlen == 0) {
434         if (s->dma) {
435             esp_raise_drq(s);
436         }
437         s->do_cmd = 1;
438         /* Target present, but no cmd yet - switch to command phase */
439         s->rregs[ESP_RSEQ] = SEQ_CD;
440         esp_set_phase(s, STAT_CD);
441     }
442 }
443 
444 static void satn_stop_pdma_cb(ESPState *s)
445 {
446     uint8_t buf[ESP_FIFO_SZ];
447     int n;
448 
449     /* Copy FIFO into cmdfifo */
450     n = esp_fifo_pop_buf(&s->fifo, buf, fifo8_num_used(&s->fifo));
451     n = MIN(fifo8_num_free(&s->cmdfifo), n);
452     fifo8_push_all(&s->cmdfifo, buf, n);
453 
454     if (!esp_get_tc(s) && !fifo8_is_empty(&s->cmdfifo)) {
455         trace_esp_handle_satn_stop(fifo8_num_used(&s->cmdfifo));
456         s->do_cmd = 1;
457         s->cmdfifo_cdb_offset = 1;
458         esp_set_phase(s, STAT_CD);
459         s->rregs[ESP_RSTAT] |= STAT_TC;
460         s->rregs[ESP_RINTR] |= INTR_BS | INTR_FC;
461         s->rregs[ESP_RSEQ] = SEQ_CD;
462         esp_raise_irq(s);
463     }
464 }
465 
466 static void handle_satn_stop(ESPState *s)
467 {
468     int32_t cmdlen;
469 
470     if (s->dma && !s->dma_enabled) {
471         s->dma_cb = handle_satn_stop;
472         return;
473     }
474     esp_set_pdma_cb(s, SATN_STOP_PDMA_CB);
475     if (esp_select(s) < 0) {
476         return;
477     }
478     cmdlen = get_cmd(s, 1);
479     if (cmdlen > 0) {
480         trace_esp_handle_satn_stop(fifo8_num_used(&s->cmdfifo));
481         s->do_cmd = 1;
482         s->cmdfifo_cdb_offset = 1;
483         esp_set_phase(s, STAT_MO);
484         s->rregs[ESP_RINTR] |= INTR_BS | INTR_FC;
485         s->rregs[ESP_RSEQ] = SEQ_MO;
486         esp_raise_irq(s);
487     } else if (cmdlen == 0) {
488         if (s->dma) {
489             esp_raise_drq(s);
490         }
491         s->do_cmd = 1;
492         /* Target present, switch to message out phase */
493         s->rregs[ESP_RSEQ] = SEQ_MO;
494         esp_set_phase(s, STAT_MO);
495     }
496 }
497 
498 static void write_response_pdma_cb(ESPState *s)
499 {
500     esp_set_phase(s, STAT_ST);
501     s->rregs[ESP_RINTR] |= INTR_BS | INTR_FC;
502     s->rregs[ESP_RSEQ] = SEQ_CD;
503     esp_raise_irq(s);
504 }
505 
506 static void write_response(ESPState *s)
507 {
508     uint8_t buf[2];
509 
510     trace_esp_write_response(s->status);
511 
512     buf[0] = s->status;
513     buf[1] = 0;
514 
515     if (s->dma) {
516         if (s->dma_memory_write) {
517             s->dma_memory_write(s->dma_opaque, buf, 2);
518             esp_set_phase(s, STAT_ST);
519             s->rregs[ESP_RINTR] |= INTR_BS | INTR_FC;
520             s->rregs[ESP_RSEQ] = SEQ_CD;
521         } else {
522             esp_set_pdma_cb(s, WRITE_RESPONSE_PDMA_CB);
523             esp_raise_drq(s);
524             return;
525         }
526     } else {
527         fifo8_reset(&s->fifo);
528         fifo8_push_all(&s->fifo, buf, 2);
529         s->rregs[ESP_RFLAGS] = 2;
530     }
531     esp_raise_irq(s);
532 }
533 
534 static void esp_dma_ti_check(ESPState *s)
535 {
536     if (esp_get_tc(s) == 0 && fifo8_num_used(&s->fifo) < 2) {
537         s->rregs[ESP_RINTR] |= INTR_BS;
538         esp_raise_irq(s);
539         esp_lower_drq(s);
540     }
541 }
542 
543 static void do_dma_pdma_cb(ESPState *s)
544 {
545     uint8_t buf[ESP_CMDFIFO_SZ];
546     int len;
547     uint32_t n;
548 
549     switch (esp_get_phase(s)) {
550     case STAT_MO:
551     case STAT_CD:
552         /* Copy FIFO into cmdfifo */
553         n = esp_fifo_pop_buf(&s->fifo, buf, fifo8_num_used(&s->fifo));
554         n = MIN(fifo8_num_free(&s->cmdfifo), n);
555         fifo8_push_all(&s->cmdfifo, buf, n);
556 
557         /* Ensure we have received complete command after SATN and stop */
558         if (esp_get_tc(s) || fifo8_is_empty(&s->cmdfifo)) {
559             return;
560         }
561 
562         s->ti_size = 0;
563         if (esp_get_phase(s) == STAT_CD) {
564             /* No command received */
565             if (s->cmdfifo_cdb_offset == fifo8_num_used(&s->cmdfifo)) {
566                 return;
567             }
568 
569             /* Command has been received */
570             s->do_cmd = 0;
571             do_cmd(s);
572         } else {
573             /*
574              * Extra message out bytes received: update cmdfifo_cdb_offset
575              * and then switch to command phase
576              */
577             s->cmdfifo_cdb_offset = fifo8_num_used(&s->cmdfifo);
578             esp_set_phase(s, STAT_CD);
579             s->rregs[ESP_RSEQ] = SEQ_CD;
580             s->rregs[ESP_RINTR] |= INTR_BS;
581             esp_raise_irq(s);
582         }
583         break;
584 
585     case STAT_DO:
586         if (!s->current_req) {
587             return;
588         }
589         /* Copy FIFO data to device */
590         len = MIN(s->async_len, ESP_FIFO_SZ);
591         len = MIN(len, fifo8_num_used(&s->fifo));
592         n = esp_fifo_pop_buf(&s->fifo, s->async_buf, len);
593         s->async_buf += n;
594         s->async_len -= n;
595         s->ti_size += n;
596 
597         if (s->async_len == 0 && fifo8_num_used(&s->fifo) < 2) {
598             /* Defer until the scsi layer has completed */
599             scsi_req_continue(s->current_req);
600             return;
601         }
602 
603         esp_dma_ti_check(s);
604         break;
605 
606     case STAT_DI:
607         if (!s->current_req) {
608             return;
609         }
610         /* Copy device data to FIFO */
611         len = MIN(s->async_len, esp_get_tc(s));
612         len = MIN(len, fifo8_num_free(&s->fifo));
613         fifo8_push_all(&s->fifo, s->async_buf, len);
614         s->async_buf += len;
615         s->async_len -= len;
616         s->ti_size -= len;
617         esp_set_tc(s, esp_get_tc(s) - len);
618 
619         if (s->async_len == 0 && fifo8_num_used(&s->fifo) < 2) {
620             /* Defer until the scsi layer has completed */
621             scsi_req_continue(s->current_req);
622             s->data_in_ready = false;
623             return;
624         }
625 
626         esp_dma_ti_check(s);
627         break;
628     }
629 }
630 
631 static void esp_do_dma(ESPState *s)
632 {
633     uint32_t len, cmdlen;
634     uint8_t buf[ESP_CMDFIFO_SZ];
635     int n;
636 
637     len = esp_get_tc(s);
638 
639     switch (esp_get_phase(s)) {
640     case STAT_MO:
641     case STAT_CD:
642         cmdlen = fifo8_num_used(&s->cmdfifo);
643         trace_esp_do_dma(cmdlen, len);
644         if (s->dma_memory_read) {
645             len = MIN(len, fifo8_num_free(&s->cmdfifo));
646             s->dma_memory_read(s->dma_opaque, buf, len);
647             fifo8_push_all(&s->cmdfifo, buf, len);
648             esp_set_tc(s, esp_get_tc(s) - len);
649         } else {
650             n = esp_fifo_pop_buf(&s->fifo, buf, fifo8_num_used(&s->fifo));
651             n = MIN(fifo8_num_free(&s->cmdfifo), n);
652             fifo8_push_all(&s->cmdfifo, buf, n);
653             esp_set_tc(s, esp_get_tc(s) - n);
654 
655             esp_set_pdma_cb(s, DO_DMA_PDMA_CB);
656             esp_raise_drq(s);
657 
658             /* Ensure we have received complete command after SATN and stop */
659             if (esp_get_tc(s) || fifo8_is_empty(&s->cmdfifo)) {
660                 return;
661             }
662         }
663         trace_esp_handle_ti_cmd(cmdlen);
664         s->ti_size = 0;
665         if (esp_get_phase(s) == STAT_CD) {
666             /* No command received */
667             if (s->cmdfifo_cdb_offset == fifo8_num_used(&s->cmdfifo)) {
668                 return;
669             }
670 
671             /* Command has been received */
672             s->do_cmd = 0;
673             do_cmd(s);
674         } else {
675             /*
676              * Extra message out bytes received: update cmdfifo_cdb_offset
677              * and then switch to command phase
678              */
679             s->cmdfifo_cdb_offset = fifo8_num_used(&s->cmdfifo);
680             esp_set_phase(s, STAT_CD);
681             s->rregs[ESP_RSEQ] = SEQ_CD;
682             s->rregs[ESP_RINTR] |= INTR_BS;
683             esp_raise_irq(s);
684         }
685         break;
686 
687     case STAT_DO:
688         if (!s->current_req) {
689             return;
690         }
691         if (s->async_len == 0 && esp_get_tc(s) && s->ti_size) {
692             /* Defer until data is available.  */
693             return;
694         }
695         if (len > s->async_len) {
696             len = s->async_len;
697         }
698         if (s->dma_memory_read) {
699             s->dma_memory_read(s->dma_opaque, s->async_buf, len);
700 
701             esp_set_tc(s, esp_get_tc(s) - len);
702             s->async_buf += len;
703             s->async_len -= len;
704             s->ti_size += len;
705 
706             if (s->async_len == 0 && fifo8_num_used(&s->fifo) < 2) {
707                 /* Defer until the scsi layer has completed */
708                 scsi_req_continue(s->current_req);
709                 return;
710             }
711 
712             esp_dma_ti_check(s);
713         } else {
714             /* Copy FIFO data to device */
715             len = MIN(s->async_len, ESP_FIFO_SZ);
716             len = MIN(len, fifo8_num_used(&s->fifo));
717             n = esp_fifo_pop_buf(&s->fifo, s->async_buf, len);
718             s->async_buf += n;
719             s->async_len -= n;
720             s->ti_size += n;
721 
722             esp_set_pdma_cb(s, DO_DMA_PDMA_CB);
723             esp_raise_drq(s);
724 
725             if (s->async_len == 0 && fifo8_num_used(&s->fifo) < 2) {
726                 /* Defer until the scsi layer has completed */
727                 scsi_req_continue(s->current_req);
728                 return;
729             }
730 
731             esp_dma_ti_check(s);
732         }
733         break;
734 
735     case STAT_DI:
736         if (!s->current_req) {
737             return;
738         }
739         if (s->async_len == 0 && esp_get_tc(s) && s->ti_size) {
740             /* Defer until data is available.  */
741             return;
742         }
743         if (len > s->async_len) {
744             len = s->async_len;
745         }
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 && fifo8_num_used(&s->fifo) < 2) {
755                 /* Defer until the scsi layer has completed */
756                 scsi_req_continue(s->current_req);
757                 return;
758             }
759 
760             esp_dma_ti_check(s);
761         } else {
762             /* Copy device data to FIFO */
763             len = MIN(len, fifo8_num_free(&s->fifo));
764             fifo8_push_all(&s->fifo, s->async_buf, len);
765             s->async_buf += len;
766             s->async_len -= len;
767             s->ti_size -= len;
768             esp_set_tc(s, esp_get_tc(s) - len);
769             esp_set_pdma_cb(s, DO_DMA_PDMA_CB);
770             esp_raise_drq(s);
771 
772             if (s->async_len == 0 && fifo8_num_used(&s->fifo) < 2) {
773                 /* Defer until the scsi layer has completed */
774                 scsi_req_continue(s->current_req);
775                 return;
776             }
777 
778             esp_dma_ti_check(s);
779         }
780         break;
781     }
782 }
783 
784 static void esp_do_nodma(ESPState *s)
785 {
786     uint8_t buf[ESP_FIFO_SZ];
787     uint32_t cmdlen;
788     int len, n;
789 
790     switch (esp_get_phase(s)) {
791     case STAT_MO:
792     case STAT_CD:
793         /* Copy FIFO into cmdfifo */
794         n = esp_fifo_pop_buf(&s->fifo, buf, fifo8_num_used(&s->fifo));
795         n = MIN(fifo8_num_free(&s->cmdfifo), n);
796         fifo8_push_all(&s->cmdfifo, buf, n);
797 
798         cmdlen = fifo8_num_used(&s->cmdfifo);
799         trace_esp_handle_ti_cmd(cmdlen);
800         s->ti_size = 0;
801         if (esp_get_phase(s) == STAT_CD) {
802             /* No command received */
803             if (s->cmdfifo_cdb_offset == fifo8_num_used(&s->cmdfifo)) {
804                 return;
805             }
806 
807             /* Command has been received */
808             s->do_cmd = 0;
809             do_cmd(s);
810         } else {
811             /*
812              * Extra message out bytes received: update cmdfifo_cdb_offset
813              * and then switch to command phase
814              */
815             s->cmdfifo_cdb_offset = fifo8_num_used(&s->cmdfifo);
816             esp_set_phase(s, STAT_CD);
817             s->rregs[ESP_RSEQ] = SEQ_CD;
818             s->rregs[ESP_RINTR] |= INTR_BS;
819             esp_raise_irq(s);
820         }
821         break;
822 
823     case STAT_DO:
824         if (!s->current_req) {
825             return;
826         }
827         if (s->async_len == 0) {
828             /* Defer until data is available.  */
829             return;
830         }
831         len = MIN(s->async_len, ESP_FIFO_SZ);
832         len = MIN(len, fifo8_num_used(&s->fifo));
833         esp_fifo_pop_buf(&s->fifo, s->async_buf, len);
834         s->async_buf += len;
835         s->async_len -= len;
836         s->ti_size += len;
837 
838         if (s->async_len == 0) {
839             scsi_req_continue(s->current_req);
840             return;
841         }
842 
843         s->rregs[ESP_RINTR] |= INTR_BS;
844         esp_raise_irq(s);
845         break;
846 
847     case STAT_DI:
848         if (!s->current_req) {
849             return;
850         }
851         if (s->async_len == 0) {
852             /* Defer until data is available.  */
853             return;
854         }
855         if (fifo8_is_empty(&s->fifo)) {
856             fifo8_push(&s->fifo, s->async_buf[0]);
857             s->async_buf++;
858             s->async_len--;
859             s->ti_size--;
860         }
861 
862         if (s->async_len == 0) {
863             scsi_req_continue(s->current_req);
864             return;
865         }
866 
867         s->rregs[ESP_RINTR] |= INTR_BS;
868         esp_raise_irq(s);
869         break;
870     }
871 }
872 
873 static void esp_pdma_cb(ESPState *s)
874 {
875     switch (s->pdma_cb) {
876     case SATN_PDMA_CB:
877         satn_pdma_cb(s);
878         break;
879     case SATN_STOP_PDMA_CB:
880         satn_stop_pdma_cb(s);
881         break;
882     case WRITE_RESPONSE_PDMA_CB:
883         write_response_pdma_cb(s);
884         break;
885     case DO_DMA_PDMA_CB:
886         do_dma_pdma_cb(s);
887         break;
888     default:
889         g_assert_not_reached();
890     }
891 }
892 
893 void esp_command_complete(SCSIRequest *req, size_t resid)
894 {
895     ESPState *s = req->hba_private;
896     int to_device = (esp_get_phase(s) == STAT_DO);
897 
898     trace_esp_command_complete();
899 
900     /*
901      * Non-DMA transfers from the target will leave the last byte in
902      * the FIFO so don't reset ti_size in this case
903      */
904     if (s->dma || to_device) {
905         if (s->ti_size != 0) {
906             trace_esp_command_complete_unexpected();
907         }
908     }
909 
910     s->async_len = 0;
911     if (req->status) {
912         trace_esp_command_complete_fail();
913     }
914     s->status = req->status;
915 
916     /*
917      * Switch to status phase. For non-DMA transfers from the target the last
918      * byte is still in the FIFO
919      */
920     esp_set_phase(s, STAT_ST);
921     if (s->ti_size == 0) {
922         /*
923          * Transfer complete: force TC to zero just in case a TI command was
924          * requested for more data than the command returns (Solaris 8 does
925          * this)
926          */
927         esp_set_tc(s, 0);
928         esp_dma_ti_check(s);
929     } else {
930         /*
931          * Transfer truncated: raise INTR_BS to indicate early change of
932          * phase
933          */
934         s->rregs[ESP_RINTR] |= INTR_BS;
935         esp_raise_irq(s);
936         s->ti_size = 0;
937     }
938 
939     if (s->current_req) {
940         scsi_req_unref(s->current_req);
941         s->current_req = NULL;
942         s->current_dev = NULL;
943     }
944 }
945 
946 void esp_transfer_data(SCSIRequest *req, uint32_t len)
947 {
948     ESPState *s = req->hba_private;
949     int to_device = (esp_get_phase(s) == STAT_DO);
950     uint32_t dmalen = esp_get_tc(s);
951 
952     assert(!s->do_cmd);
953     trace_esp_transfer_data(dmalen, s->ti_size);
954     s->async_len = len;
955     s->async_buf = scsi_req_get_buf(req);
956 
957     if (!to_device && !s->data_in_ready) {
958         /*
959          * Initial incoming data xfer is complete so raise command
960          * completion interrupt
961          */
962         s->data_in_ready = true;
963         s->rregs[ESP_RINTR] |= INTR_BS;
964         esp_raise_irq(s);
965     }
966 
967     /*
968      * Always perform the initial transfer upon reception of the next TI
969      * command to ensure the DMA/non-DMA status of the command is correct.
970      * It is not possible to use s->dma directly in the section below as
971      * some OSs send non-DMA NOP commands after a DMA transfer. Hence if the
972      * async data transfer is delayed then s->dma is set incorrectly.
973      */
974 
975     if (s->ti_cmd == (CMD_TI | CMD_DMA)) {
976         /* When the SCSI layer returns more data, raise deferred INTR_BS */
977         esp_dma_ti_check(s);
978 
979         esp_do_dma(s);
980     } else if (s->ti_cmd == CMD_TI) {
981         esp_do_nodma(s);
982     }
983 }
984 
985 static void handle_ti(ESPState *s)
986 {
987     uint32_t dmalen;
988 
989     if (s->dma && !s->dma_enabled) {
990         s->dma_cb = handle_ti;
991         return;
992     }
993 
994     s->ti_cmd = s->rregs[ESP_CMD];
995     if (s->dma) {
996         dmalen = esp_get_tc(s);
997         trace_esp_handle_ti(dmalen);
998         esp_do_dma(s);
999     } else {
1000         trace_esp_handle_ti(s->ti_size);
1001         esp_do_nodma(s);
1002     }
1003 }
1004 
1005 void esp_hard_reset(ESPState *s)
1006 {
1007     memset(s->rregs, 0, ESP_REGS);
1008     memset(s->wregs, 0, ESP_REGS);
1009     s->tchi_written = 0;
1010     s->ti_size = 0;
1011     s->async_len = 0;
1012     fifo8_reset(&s->fifo);
1013     fifo8_reset(&s->cmdfifo);
1014     s->dma = 0;
1015     s->do_cmd = 0;
1016     s->dma_cb = NULL;
1017 
1018     s->rregs[ESP_CFG1] = 7;
1019 }
1020 
1021 static void esp_soft_reset(ESPState *s)
1022 {
1023     qemu_irq_lower(s->irq);
1024     qemu_irq_lower(s->irq_data);
1025     esp_hard_reset(s);
1026 }
1027 
1028 static void esp_bus_reset(ESPState *s)
1029 {
1030     bus_cold_reset(BUS(&s->bus));
1031 }
1032 
1033 static void parent_esp_reset(ESPState *s, int irq, int level)
1034 {
1035     if (level) {
1036         esp_soft_reset(s);
1037     }
1038 }
1039 
1040 static void esp_run_cmd(ESPState *s)
1041 {
1042     uint8_t cmd = s->rregs[ESP_CMD];
1043 
1044     if (cmd & CMD_DMA) {
1045         s->dma = 1;
1046         /* Reload DMA counter.  */
1047         if (esp_get_stc(s) == 0) {
1048             esp_set_tc(s, 0x10000);
1049         } else {
1050             esp_set_tc(s, esp_get_stc(s));
1051         }
1052     } else {
1053         s->dma = 0;
1054     }
1055     switch (cmd & CMD_CMD) {
1056     case CMD_NOP:
1057         trace_esp_mem_writeb_cmd_nop(cmd);
1058         break;
1059     case CMD_FLUSH:
1060         trace_esp_mem_writeb_cmd_flush(cmd);
1061         fifo8_reset(&s->fifo);
1062         break;
1063     case CMD_RESET:
1064         trace_esp_mem_writeb_cmd_reset(cmd);
1065         esp_soft_reset(s);
1066         break;
1067     case CMD_BUSRESET:
1068         trace_esp_mem_writeb_cmd_bus_reset(cmd);
1069         esp_bus_reset(s);
1070         if (!(s->wregs[ESP_CFG1] & CFG1_RESREPT)) {
1071             s->rregs[ESP_RINTR] |= INTR_RST;
1072             esp_raise_irq(s);
1073         }
1074         break;
1075     case CMD_TI:
1076         trace_esp_mem_writeb_cmd_ti(cmd);
1077         handle_ti(s);
1078         break;
1079     case CMD_ICCS:
1080         trace_esp_mem_writeb_cmd_iccs(cmd);
1081         write_response(s);
1082         s->rregs[ESP_RINTR] |= INTR_FC;
1083         esp_set_phase(s, STAT_MI);
1084         break;
1085     case CMD_MSGACC:
1086         trace_esp_mem_writeb_cmd_msgacc(cmd);
1087         s->rregs[ESP_RINTR] |= INTR_DC;
1088         s->rregs[ESP_RSEQ] = 0;
1089         s->rregs[ESP_RFLAGS] = 0;
1090         esp_raise_irq(s);
1091         break;
1092     case CMD_PAD:
1093         trace_esp_mem_writeb_cmd_pad(cmd);
1094         s->rregs[ESP_RSTAT] = STAT_TC;
1095         s->rregs[ESP_RINTR] |= INTR_FC;
1096         s->rregs[ESP_RSEQ] = 0;
1097         break;
1098     case CMD_SATN:
1099         trace_esp_mem_writeb_cmd_satn(cmd);
1100         break;
1101     case CMD_RSTATN:
1102         trace_esp_mem_writeb_cmd_rstatn(cmd);
1103         break;
1104     case CMD_SEL:
1105         trace_esp_mem_writeb_cmd_sel(cmd);
1106         handle_s_without_atn(s);
1107         break;
1108     case CMD_SELATN:
1109         trace_esp_mem_writeb_cmd_selatn(cmd);
1110         handle_satn(s);
1111         break;
1112     case CMD_SELATNS:
1113         trace_esp_mem_writeb_cmd_selatns(cmd);
1114         handle_satn_stop(s);
1115         break;
1116     case CMD_ENSEL:
1117         trace_esp_mem_writeb_cmd_ensel(cmd);
1118         s->rregs[ESP_RINTR] = 0;
1119         break;
1120     case CMD_DISSEL:
1121         trace_esp_mem_writeb_cmd_dissel(cmd);
1122         s->rregs[ESP_RINTR] = 0;
1123         esp_raise_irq(s);
1124         break;
1125     default:
1126         trace_esp_error_unhandled_command(cmd);
1127         break;
1128     }
1129 }
1130 
1131 uint64_t esp_reg_read(ESPState *s, uint32_t saddr)
1132 {
1133     uint32_t val;
1134 
1135     switch (saddr) {
1136     case ESP_FIFO:
1137         if (s->dma_memory_read && s->dma_memory_write &&
1138                 (s->rregs[ESP_RSTAT] & STAT_PIO_MASK) == 0) {
1139             /* Data out.  */
1140             qemu_log_mask(LOG_UNIMP, "esp: PIO data read not implemented\n");
1141             s->rregs[ESP_FIFO] = 0;
1142         } else {
1143             if (esp_get_phase(s) == STAT_DI) {
1144                 if (s->ti_size) {
1145                     esp_do_nodma(s);
1146                 } else {
1147                     /*
1148                      * The last byte of a non-DMA transfer has been read out
1149                      * of the FIFO so switch to status phase
1150                      */
1151                     esp_set_phase(s, STAT_ST);
1152                 }
1153             }
1154             s->rregs[ESP_FIFO] = esp_fifo_pop(&s->fifo);
1155         }
1156         val = s->rregs[ESP_FIFO];
1157         break;
1158     case ESP_RINTR:
1159         /*
1160          * Clear sequence step, interrupt register and all status bits
1161          * except TC
1162          */
1163         val = s->rregs[ESP_RINTR];
1164         s->rregs[ESP_RINTR] = 0;
1165         s->rregs[ESP_RSTAT] &= ~STAT_TC;
1166         /*
1167          * According to the datasheet ESP_RSEQ should be cleared, but as the
1168          * emulation currently defers information transfers to the next TI
1169          * command leave it for now so that pedantic guests such as the old
1170          * Linux 2.6 driver see the correct flags before the next SCSI phase
1171          * transition.
1172          *
1173          * s->rregs[ESP_RSEQ] = SEQ_0;
1174          */
1175         esp_lower_irq(s);
1176         break;
1177     case ESP_TCHI:
1178         /* Return the unique id if the value has never been written */
1179         if (!s->tchi_written) {
1180             val = s->chip_id;
1181         } else {
1182             val = s->rregs[saddr];
1183         }
1184         break;
1185      case ESP_RFLAGS:
1186         /* Bottom 5 bits indicate number of bytes in FIFO */
1187         val = fifo8_num_used(&s->fifo);
1188         break;
1189     default:
1190         val = s->rregs[saddr];
1191         break;
1192     }
1193 
1194     trace_esp_mem_readb(saddr, val);
1195     return val;
1196 }
1197 
1198 void esp_reg_write(ESPState *s, uint32_t saddr, uint64_t val)
1199 {
1200     trace_esp_mem_writeb(saddr, s->wregs[saddr], val);
1201     switch (saddr) {
1202     case ESP_TCHI:
1203         s->tchi_written = true;
1204         /* fall through */
1205     case ESP_TCLO:
1206     case ESP_TCMID:
1207         s->rregs[ESP_RSTAT] &= ~STAT_TC;
1208         break;
1209     case ESP_FIFO:
1210         if (esp_get_phase(s) == STAT_MO || esp_get_phase(s) == STAT_CD) {
1211             if (!fifo8_is_full(&s->fifo)) {
1212                 esp_fifo_push(&s->fifo, val);
1213                 esp_fifo_push(&s->cmdfifo, fifo8_pop(&s->fifo));
1214             }
1215 
1216             /*
1217              * If any unexpected message out/command phase data is
1218              * transferred using non-DMA, raise the interrupt
1219              */
1220             if (s->rregs[ESP_CMD] == CMD_TI) {
1221                 s->rregs[ESP_RINTR] |= INTR_BS;
1222                 esp_raise_irq(s);
1223             }
1224         } else {
1225             esp_fifo_push(&s->fifo, val);
1226         }
1227         break;
1228     case ESP_CMD:
1229         s->rregs[saddr] = val;
1230         esp_run_cmd(s);
1231         break;
1232     case ESP_WBUSID ... ESP_WSYNO:
1233         break;
1234     case ESP_CFG1:
1235     case ESP_CFG2: case ESP_CFG3:
1236     case ESP_RES3: case ESP_RES4:
1237         s->rregs[saddr] = val;
1238         break;
1239     case ESP_WCCF ... ESP_WTEST:
1240         break;
1241     default:
1242         trace_esp_error_invalid_write(val, saddr);
1243         return;
1244     }
1245     s->wregs[saddr] = val;
1246 }
1247 
1248 static bool esp_mem_accepts(void *opaque, hwaddr addr,
1249                             unsigned size, bool is_write,
1250                             MemTxAttrs attrs)
1251 {
1252     return (size == 1) || (is_write && size == 4);
1253 }
1254 
1255 static bool esp_is_before_version_5(void *opaque, int version_id)
1256 {
1257     ESPState *s = ESP(opaque);
1258 
1259     version_id = MIN(version_id, s->mig_version_id);
1260     return version_id < 5;
1261 }
1262 
1263 static bool esp_is_version_5(void *opaque, int version_id)
1264 {
1265     ESPState *s = ESP(opaque);
1266 
1267     version_id = MIN(version_id, s->mig_version_id);
1268     return version_id >= 5;
1269 }
1270 
1271 static bool esp_is_version_6(void *opaque, int version_id)
1272 {
1273     ESPState *s = ESP(opaque);
1274 
1275     version_id = MIN(version_id, s->mig_version_id);
1276     return version_id >= 6;
1277 }
1278 
1279 int esp_pre_save(void *opaque)
1280 {
1281     ESPState *s = ESP(object_resolve_path_component(
1282                       OBJECT(opaque), "esp"));
1283 
1284     s->mig_version_id = vmstate_esp.version_id;
1285     return 0;
1286 }
1287 
1288 static int esp_post_load(void *opaque, int version_id)
1289 {
1290     ESPState *s = ESP(opaque);
1291     int len, i;
1292 
1293     version_id = MIN(version_id, s->mig_version_id);
1294 
1295     if (version_id < 5) {
1296         esp_set_tc(s, s->mig_dma_left);
1297 
1298         /* Migrate ti_buf to fifo */
1299         len = s->mig_ti_wptr - s->mig_ti_rptr;
1300         for (i = 0; i < len; i++) {
1301             fifo8_push(&s->fifo, s->mig_ti_buf[i]);
1302         }
1303 
1304         /* Migrate cmdbuf to cmdfifo */
1305         for (i = 0; i < s->mig_cmdlen; i++) {
1306             fifo8_push(&s->cmdfifo, s->mig_cmdbuf[i]);
1307         }
1308     }
1309 
1310     s->mig_version_id = vmstate_esp.version_id;
1311     return 0;
1312 }
1313 
1314 /*
1315  * PDMA (or pseudo-DMA) is only used on the Macintosh and requires the
1316  * guest CPU to perform the transfers between the SCSI bus and memory
1317  * itself. This is indicated by the dma_memory_read and dma_memory_write
1318  * functions being NULL (in contrast to the ESP PCI device) whilst
1319  * dma_enabled is still set.
1320  */
1321 
1322 static bool esp_pdma_needed(void *opaque)
1323 {
1324     ESPState *s = ESP(opaque);
1325 
1326     return s->dma_memory_read == NULL && s->dma_memory_write == NULL &&
1327            s->dma_enabled;
1328 }
1329 
1330 static const VMStateDescription vmstate_esp_pdma = {
1331     .name = "esp/pdma",
1332     .version_id = 0,
1333     .minimum_version_id = 0,
1334     .needed = esp_pdma_needed,
1335     .fields = (const VMStateField[]) {
1336         VMSTATE_UINT8(pdma_cb, ESPState),
1337         VMSTATE_END_OF_LIST()
1338     }
1339 };
1340 
1341 const VMStateDescription vmstate_esp = {
1342     .name = "esp",
1343     .version_id = 6,
1344     .minimum_version_id = 3,
1345     .post_load = esp_post_load,
1346     .fields = (const VMStateField[]) {
1347         VMSTATE_BUFFER(rregs, ESPState),
1348         VMSTATE_BUFFER(wregs, ESPState),
1349         VMSTATE_INT32(ti_size, ESPState),
1350         VMSTATE_UINT32_TEST(mig_ti_rptr, ESPState, esp_is_before_version_5),
1351         VMSTATE_UINT32_TEST(mig_ti_wptr, ESPState, esp_is_before_version_5),
1352         VMSTATE_BUFFER_TEST(mig_ti_buf, ESPState, esp_is_before_version_5),
1353         VMSTATE_UINT32(status, ESPState),
1354         VMSTATE_UINT32_TEST(mig_deferred_status, ESPState,
1355                             esp_is_before_version_5),
1356         VMSTATE_BOOL_TEST(mig_deferred_complete, ESPState,
1357                           esp_is_before_version_5),
1358         VMSTATE_UINT32(dma, ESPState),
1359         VMSTATE_STATIC_BUFFER(mig_cmdbuf, ESPState, 0,
1360                               esp_is_before_version_5, 0, 16),
1361         VMSTATE_STATIC_BUFFER(mig_cmdbuf, ESPState, 4,
1362                               esp_is_before_version_5, 16,
1363                               sizeof(typeof_field(ESPState, mig_cmdbuf))),
1364         VMSTATE_UINT32_TEST(mig_cmdlen, ESPState, esp_is_before_version_5),
1365         VMSTATE_UINT32(do_cmd, ESPState),
1366         VMSTATE_UINT32_TEST(mig_dma_left, ESPState, esp_is_before_version_5),
1367         VMSTATE_BOOL_TEST(data_in_ready, ESPState, esp_is_version_5),
1368         VMSTATE_UINT8_TEST(cmdfifo_cdb_offset, ESPState, esp_is_version_5),
1369         VMSTATE_FIFO8_TEST(fifo, ESPState, esp_is_version_5),
1370         VMSTATE_FIFO8_TEST(cmdfifo, ESPState, esp_is_version_5),
1371         VMSTATE_UINT8_TEST(ti_cmd, ESPState, esp_is_version_5),
1372         VMSTATE_UINT8_TEST(lun, ESPState, esp_is_version_6),
1373         VMSTATE_END_OF_LIST()
1374     },
1375     .subsections = (const VMStateDescription * const []) {
1376         &vmstate_esp_pdma,
1377         NULL
1378     }
1379 };
1380 
1381 static void sysbus_esp_mem_write(void *opaque, hwaddr addr,
1382                                  uint64_t val, unsigned int size)
1383 {
1384     SysBusESPState *sysbus = opaque;
1385     ESPState *s = ESP(&sysbus->esp);
1386     uint32_t saddr;
1387 
1388     saddr = addr >> sysbus->it_shift;
1389     esp_reg_write(s, saddr, val);
1390 }
1391 
1392 static uint64_t sysbus_esp_mem_read(void *opaque, hwaddr addr,
1393                                     unsigned int size)
1394 {
1395     SysBusESPState *sysbus = opaque;
1396     ESPState *s = ESP(&sysbus->esp);
1397     uint32_t saddr;
1398 
1399     saddr = addr >> sysbus->it_shift;
1400     return esp_reg_read(s, saddr);
1401 }
1402 
1403 static const MemoryRegionOps sysbus_esp_mem_ops = {
1404     .read = sysbus_esp_mem_read,
1405     .write = sysbus_esp_mem_write,
1406     .endianness = DEVICE_NATIVE_ENDIAN,
1407     .valid.accepts = esp_mem_accepts,
1408 };
1409 
1410 static void sysbus_esp_pdma_write(void *opaque, hwaddr addr,
1411                                   uint64_t val, unsigned int size)
1412 {
1413     SysBusESPState *sysbus = opaque;
1414     ESPState *s = ESP(&sysbus->esp);
1415 
1416     trace_esp_pdma_write(size);
1417 
1418     switch (size) {
1419     case 1:
1420         esp_pdma_write(s, val);
1421         break;
1422     case 2:
1423         esp_pdma_write(s, val >> 8);
1424         esp_pdma_write(s, val);
1425         break;
1426     }
1427     esp_pdma_cb(s);
1428 }
1429 
1430 static uint64_t sysbus_esp_pdma_read(void *opaque, hwaddr addr,
1431                                      unsigned int size)
1432 {
1433     SysBusESPState *sysbus = opaque;
1434     ESPState *s = ESP(&sysbus->esp);
1435     uint64_t val = 0;
1436 
1437     trace_esp_pdma_read(size);
1438 
1439     switch (size) {
1440     case 1:
1441         val = esp_pdma_read(s);
1442         break;
1443     case 2:
1444         val = esp_pdma_read(s);
1445         val = (val << 8) | esp_pdma_read(s);
1446         break;
1447     }
1448     esp_pdma_cb(s);
1449     return val;
1450 }
1451 
1452 static void *esp_load_request(QEMUFile *f, SCSIRequest *req)
1453 {
1454     ESPState *s = container_of(req->bus, ESPState, bus);
1455 
1456     scsi_req_ref(req);
1457     s->current_req = req;
1458     return s;
1459 }
1460 
1461 static const MemoryRegionOps sysbus_esp_pdma_ops = {
1462     .read = sysbus_esp_pdma_read,
1463     .write = sysbus_esp_pdma_write,
1464     .endianness = DEVICE_NATIVE_ENDIAN,
1465     .valid.min_access_size = 1,
1466     .valid.max_access_size = 4,
1467     .impl.min_access_size = 1,
1468     .impl.max_access_size = 2,
1469 };
1470 
1471 static const struct SCSIBusInfo esp_scsi_info = {
1472     .tcq = false,
1473     .max_target = ESP_MAX_DEVS,
1474     .max_lun = 7,
1475 
1476     .load_request = esp_load_request,
1477     .transfer_data = esp_transfer_data,
1478     .complete = esp_command_complete,
1479     .cancel = esp_request_cancelled
1480 };
1481 
1482 static void sysbus_esp_gpio_demux(void *opaque, int irq, int level)
1483 {
1484     SysBusESPState *sysbus = SYSBUS_ESP(opaque);
1485     ESPState *s = ESP(&sysbus->esp);
1486 
1487     switch (irq) {
1488     case 0:
1489         parent_esp_reset(s, irq, level);
1490         break;
1491     case 1:
1492         esp_dma_enable(s, irq, level);
1493         break;
1494     }
1495 }
1496 
1497 static void sysbus_esp_realize(DeviceState *dev, Error **errp)
1498 {
1499     SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
1500     SysBusESPState *sysbus = SYSBUS_ESP(dev);
1501     ESPState *s = ESP(&sysbus->esp);
1502 
1503     if (!qdev_realize(DEVICE(s), NULL, errp)) {
1504         return;
1505     }
1506 
1507     sysbus_init_irq(sbd, &s->irq);
1508     sysbus_init_irq(sbd, &s->irq_data);
1509     assert(sysbus->it_shift != -1);
1510 
1511     s->chip_id = TCHI_FAS100A;
1512     memory_region_init_io(&sysbus->iomem, OBJECT(sysbus), &sysbus_esp_mem_ops,
1513                           sysbus, "esp-regs", ESP_REGS << sysbus->it_shift);
1514     sysbus_init_mmio(sbd, &sysbus->iomem);
1515     memory_region_init_io(&sysbus->pdma, OBJECT(sysbus), &sysbus_esp_pdma_ops,
1516                           sysbus, "esp-pdma", 4);
1517     sysbus_init_mmio(sbd, &sysbus->pdma);
1518 
1519     qdev_init_gpio_in(dev, sysbus_esp_gpio_demux, 2);
1520 
1521     scsi_bus_init(&s->bus, sizeof(s->bus), dev, &esp_scsi_info);
1522 }
1523 
1524 static void sysbus_esp_hard_reset(DeviceState *dev)
1525 {
1526     SysBusESPState *sysbus = SYSBUS_ESP(dev);
1527     ESPState *s = ESP(&sysbus->esp);
1528 
1529     esp_hard_reset(s);
1530 }
1531 
1532 static void sysbus_esp_init(Object *obj)
1533 {
1534     SysBusESPState *sysbus = SYSBUS_ESP(obj);
1535 
1536     object_initialize_child(obj, "esp", &sysbus->esp, TYPE_ESP);
1537 }
1538 
1539 static const VMStateDescription vmstate_sysbus_esp_scsi = {
1540     .name = "sysbusespscsi",
1541     .version_id = 2,
1542     .minimum_version_id = 1,
1543     .pre_save = esp_pre_save,
1544     .fields = (const VMStateField[]) {
1545         VMSTATE_UINT8_V(esp.mig_version_id, SysBusESPState, 2),
1546         VMSTATE_STRUCT(esp, SysBusESPState, 0, vmstate_esp, ESPState),
1547         VMSTATE_END_OF_LIST()
1548     }
1549 };
1550 
1551 static void sysbus_esp_class_init(ObjectClass *klass, void *data)
1552 {
1553     DeviceClass *dc = DEVICE_CLASS(klass);
1554 
1555     dc->realize = sysbus_esp_realize;
1556     dc->reset = sysbus_esp_hard_reset;
1557     dc->vmsd = &vmstate_sysbus_esp_scsi;
1558     set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
1559 }
1560 
1561 static const TypeInfo sysbus_esp_info = {
1562     .name          = TYPE_SYSBUS_ESP,
1563     .parent        = TYPE_SYS_BUS_DEVICE,
1564     .instance_init = sysbus_esp_init,
1565     .instance_size = sizeof(SysBusESPState),
1566     .class_init    = sysbus_esp_class_init,
1567 };
1568 
1569 static void esp_finalize(Object *obj)
1570 {
1571     ESPState *s = ESP(obj);
1572 
1573     fifo8_destroy(&s->fifo);
1574     fifo8_destroy(&s->cmdfifo);
1575 }
1576 
1577 static void esp_init(Object *obj)
1578 {
1579     ESPState *s = ESP(obj);
1580 
1581     fifo8_create(&s->fifo, ESP_FIFO_SZ);
1582     fifo8_create(&s->cmdfifo, ESP_CMDFIFO_SZ);
1583 }
1584 
1585 static void esp_class_init(ObjectClass *klass, void *data)
1586 {
1587     DeviceClass *dc = DEVICE_CLASS(klass);
1588 
1589     /* internal device for sysbusesp/pciespscsi, not user-creatable */
1590     dc->user_creatable = false;
1591     set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
1592 }
1593 
1594 static const TypeInfo esp_info = {
1595     .name = TYPE_ESP,
1596     .parent = TYPE_DEVICE,
1597     .instance_init = esp_init,
1598     .instance_finalize = esp_finalize,
1599     .instance_size = sizeof(ESPState),
1600     .class_init = esp_class_init,
1601 };
1602 
1603 static void esp_register_types(void)
1604 {
1605     type_register_static(&sysbus_esp_info);
1606     type_register_static(&esp_info);
1607 }
1608 
1609 type_init(esp_register_types)
1610