xref: /qemu/hw/scsi/esp.c (revision 9d1aa52b761bc9e38d19009ada723bd4f734cd90)
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     if (s->do_cmd) {
550         /* Copy FIFO into cmdfifo */
551         n = esp_fifo_pop_buf(&s->fifo, buf, fifo8_num_used(&s->fifo));
552         n = MIN(fifo8_num_free(&s->cmdfifo), n);
553         fifo8_push_all(&s->cmdfifo, buf, n);
554 
555         /* Ensure we have received complete command after SATN and stop */
556         if (esp_get_tc(s) || fifo8_is_empty(&s->cmdfifo)) {
557             return;
558         }
559 
560         s->ti_size = 0;
561         if (esp_get_phase(s) == STAT_CD) {
562             /* No command received */
563             if (s->cmdfifo_cdb_offset == fifo8_num_used(&s->cmdfifo)) {
564                 return;
565             }
566 
567             /* Command has been received */
568             s->do_cmd = 0;
569             do_cmd(s);
570         } else {
571             /*
572              * Extra message out bytes received: update cmdfifo_cdb_offset
573              * and then switch to command phase
574              */
575             s->cmdfifo_cdb_offset = fifo8_num_used(&s->cmdfifo);
576             esp_set_phase(s, STAT_CD);
577             s->rregs[ESP_RSEQ] = SEQ_CD;
578             s->rregs[ESP_RINTR] |= INTR_BS;
579             esp_raise_irq(s);
580         }
581         return;
582     }
583 
584     switch (esp_get_phase(s)) {
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     if (s->do_cmd) {
639         /*
640          * handle_ti_cmd() case: esp_do_dma() is called only from
641          * handle_ti_cmd() with do_cmd != NULL (see the assert())
642          */
643         cmdlen = fifo8_num_used(&s->cmdfifo);
644         trace_esp_do_dma(cmdlen, len);
645         if (s->dma_memory_read) {
646             len = MIN(len, fifo8_num_free(&s->cmdfifo));
647             s->dma_memory_read(s->dma_opaque, buf, len);
648             fifo8_push_all(&s->cmdfifo, buf, len);
649             esp_set_tc(s, esp_get_tc(s) - len);
650         } else {
651             n = esp_fifo_pop_buf(&s->fifo, buf, fifo8_num_used(&s->fifo));
652             n = MIN(fifo8_num_free(&s->cmdfifo), n);
653             fifo8_push_all(&s->cmdfifo, buf, n);
654             esp_set_tc(s, esp_get_tc(s) - n);
655 
656             esp_set_pdma_cb(s, DO_DMA_PDMA_CB);
657             esp_raise_drq(s);
658 
659             /* Ensure we have received complete command after SATN and stop */
660             if (esp_get_tc(s) || fifo8_is_empty(&s->cmdfifo)) {
661                 return;
662             }
663         }
664         trace_esp_handle_ti_cmd(cmdlen);
665         s->ti_size = 0;
666         if (esp_get_phase(s) == STAT_CD) {
667             /* No command received */
668             if (s->cmdfifo_cdb_offset == fifo8_num_used(&s->cmdfifo)) {
669                 return;
670             }
671 
672             /* Command has been received */
673             s->do_cmd = 0;
674             do_cmd(s);
675         } else {
676             /*
677              * Extra message out bytes received: update cmdfifo_cdb_offset
678              * and then switch to command phase
679              */
680             s->cmdfifo_cdb_offset = fifo8_num_used(&s->cmdfifo);
681             esp_set_phase(s, STAT_CD);
682             s->rregs[ESP_RSEQ] = SEQ_CD;
683             s->rregs[ESP_RINTR] |= INTR_BS;
684             esp_raise_irq(s);
685         }
686         return;
687     }
688 
689     switch (esp_get_phase(s)) {
690     case STAT_DO:
691         if (!s->current_req) {
692             return;
693         }
694         if (s->async_len == 0 && esp_get_tc(s) && s->ti_size) {
695             /* Defer until data is available.  */
696             return;
697         }
698         if (len > s->async_len) {
699             len = s->async_len;
700         }
701         if (s->dma_memory_read) {
702             s->dma_memory_read(s->dma_opaque, s->async_buf, len);
703 
704             esp_set_tc(s, esp_get_tc(s) - len);
705             s->async_buf += len;
706             s->async_len -= len;
707             s->ti_size += len;
708 
709             if (s->async_len == 0 && fifo8_num_used(&s->fifo) < 2) {
710                 /* Defer until the scsi layer has completed */
711                 scsi_req_continue(s->current_req);
712                 return;
713             }
714 
715             esp_dma_ti_check(s);
716         } else {
717             /* Copy FIFO data to device */
718             len = MIN(s->async_len, ESP_FIFO_SZ);
719             len = MIN(len, fifo8_num_used(&s->fifo));
720             n = esp_fifo_pop_buf(&s->fifo, s->async_buf, len);
721             s->async_buf += n;
722             s->async_len -= n;
723             s->ti_size += n;
724 
725             esp_set_pdma_cb(s, DO_DMA_PDMA_CB);
726             esp_raise_drq(s);
727 
728             if (s->async_len == 0 && fifo8_num_used(&s->fifo) < 2) {
729                 /* Defer until the scsi layer has completed */
730                 scsi_req_continue(s->current_req);
731                 return;
732             }
733 
734             esp_dma_ti_check(s);
735         }
736         break;
737 
738     case STAT_DI:
739         if (!s->current_req) {
740             return;
741         }
742         if (s->async_len == 0 && esp_get_tc(s) && s->ti_size) {
743             /* Defer until data is available.  */
744             return;
745         }
746         if (len > s->async_len) {
747             len = s->async_len;
748         }
749         if (s->dma_memory_write) {
750             s->dma_memory_write(s->dma_opaque, s->async_buf, len);
751 
752             esp_set_tc(s, esp_get_tc(s) - len);
753             s->async_buf += len;
754             s->async_len -= len;
755             s->ti_size -= len;
756 
757             if (s->async_len == 0 && fifo8_num_used(&s->fifo) < 2) {
758                 /* Defer until the scsi layer has completed */
759                 scsi_req_continue(s->current_req);
760                 return;
761             }
762 
763             esp_dma_ti_check(s);
764         } else {
765             /* Copy device data to FIFO */
766             len = MIN(len, fifo8_num_free(&s->fifo));
767             fifo8_push_all(&s->fifo, s->async_buf, len);
768             s->async_buf += len;
769             s->async_len -= len;
770             s->ti_size -= len;
771             esp_set_tc(s, esp_get_tc(s) - len);
772             esp_set_pdma_cb(s, DO_DMA_PDMA_CB);
773             esp_raise_drq(s);
774 
775             if (s->async_len == 0 && fifo8_num_used(&s->fifo) < 2) {
776                 /* Defer until the scsi layer has completed */
777                 scsi_req_continue(s->current_req);
778                 return;
779             }
780 
781             esp_dma_ti_check(s);
782         }
783         break;
784     }
785 }
786 
787 static void esp_do_nodma(ESPState *s)
788 {
789     uint8_t buf[ESP_FIFO_SZ];
790     uint32_t cmdlen;
791     int len, n;
792 
793     if (s->do_cmd) {
794         /* Copy FIFO into cmdfifo */
795         n = esp_fifo_pop_buf(&s->fifo, buf, fifo8_num_used(&s->fifo));
796         n = MIN(fifo8_num_free(&s->cmdfifo), n);
797         fifo8_push_all(&s->cmdfifo, buf, n);
798 
799         cmdlen = fifo8_num_used(&s->cmdfifo);
800         trace_esp_handle_ti_cmd(cmdlen);
801         s->ti_size = 0;
802         if (esp_get_phase(s) == STAT_CD) {
803             /* No command received */
804             if (s->cmdfifo_cdb_offset == fifo8_num_used(&s->cmdfifo)) {
805                 return;
806             }
807 
808             /* Command has been received */
809             s->do_cmd = 0;
810             do_cmd(s);
811         } else {
812             /*
813              * Extra message out bytes received: update cmdfifo_cdb_offset
814              * and then switch to command phase
815              */
816             s->cmdfifo_cdb_offset = fifo8_num_used(&s->cmdfifo);
817             esp_set_phase(s, STAT_CD);
818             s->rregs[ESP_RSEQ] = SEQ_CD;
819             s->rregs[ESP_RINTR] |= INTR_BS;
820             esp_raise_irq(s);
821         }
822         return;
823     }
824 
825     switch (esp_get_phase(s)) {
826     case STAT_DO:
827         if (!s->current_req) {
828             return;
829         }
830         if (s->async_len == 0) {
831             /* Defer until data is available.  */
832             return;
833         }
834         len = MIN(s->async_len, ESP_FIFO_SZ);
835         len = MIN(len, fifo8_num_used(&s->fifo));
836         esp_fifo_pop_buf(&s->fifo, s->async_buf, len);
837         s->async_buf += len;
838         s->async_len -= len;
839         s->ti_size += len;
840 
841         if (s->async_len == 0) {
842             scsi_req_continue(s->current_req);
843             return;
844         }
845 
846         s->rregs[ESP_RINTR] |= INTR_BS;
847         esp_raise_irq(s);
848         break;
849 
850     case STAT_DI:
851         if (!s->current_req) {
852             return;
853         }
854         if (s->async_len == 0) {
855             /* Defer until data is available.  */
856             return;
857         }
858         if (fifo8_is_empty(&s->fifo)) {
859             fifo8_push(&s->fifo, s->async_buf[0]);
860             s->async_buf++;
861             s->async_len--;
862             s->ti_size--;
863         }
864 
865         if (s->async_len == 0) {
866             scsi_req_continue(s->current_req);
867             return;
868         }
869 
870         s->rregs[ESP_RINTR] |= INTR_BS;
871         esp_raise_irq(s);
872         break;
873     }
874 }
875 
876 static void esp_pdma_cb(ESPState *s)
877 {
878     switch (s->pdma_cb) {
879     case SATN_PDMA_CB:
880         satn_pdma_cb(s);
881         break;
882     case SATN_STOP_PDMA_CB:
883         satn_stop_pdma_cb(s);
884         break;
885     case WRITE_RESPONSE_PDMA_CB:
886         write_response_pdma_cb(s);
887         break;
888     case DO_DMA_PDMA_CB:
889         do_dma_pdma_cb(s);
890         break;
891     default:
892         g_assert_not_reached();
893     }
894 }
895 
896 void esp_command_complete(SCSIRequest *req, size_t resid)
897 {
898     ESPState *s = req->hba_private;
899     int to_device = (esp_get_phase(s) == STAT_DO);
900 
901     trace_esp_command_complete();
902 
903     /*
904      * Non-DMA transfers from the target will leave the last byte in
905      * the FIFO so don't reset ti_size in this case
906      */
907     if (s->dma || to_device) {
908         if (s->ti_size != 0) {
909             trace_esp_command_complete_unexpected();
910         }
911     }
912 
913     s->async_len = 0;
914     if (req->status) {
915         trace_esp_command_complete_fail();
916     }
917     s->status = req->status;
918 
919     /*
920      * Switch to status phase. For non-DMA transfers from the target the last
921      * byte is still in the FIFO
922      */
923     esp_set_phase(s, STAT_ST);
924     if (s->ti_size == 0) {
925         /*
926          * Transfer complete: force TC to zero just in case a TI command was
927          * requested for more data than the command returns (Solaris 8 does
928          * this)
929          */
930         esp_set_tc(s, 0);
931         esp_dma_ti_check(s);
932     } else {
933         /*
934          * Transfer truncated: raise INTR_BS to indicate early change of
935          * phase
936          */
937         s->rregs[ESP_RINTR] |= INTR_BS;
938         esp_raise_irq(s);
939         s->ti_size = 0;
940     }
941 
942     if (s->current_req) {
943         scsi_req_unref(s->current_req);
944         s->current_req = NULL;
945         s->current_dev = NULL;
946     }
947 }
948 
949 void esp_transfer_data(SCSIRequest *req, uint32_t len)
950 {
951     ESPState *s = req->hba_private;
952     int to_device = (esp_get_phase(s) == STAT_DO);
953     uint32_t dmalen = esp_get_tc(s);
954 
955     assert(!s->do_cmd);
956     trace_esp_transfer_data(dmalen, s->ti_size);
957     s->async_len = len;
958     s->async_buf = scsi_req_get_buf(req);
959 
960     if (!to_device && !s->data_in_ready) {
961         /*
962          * Initial incoming data xfer is complete so raise command
963          * completion interrupt
964          */
965         s->data_in_ready = true;
966         s->rregs[ESP_RINTR] |= INTR_BS;
967         esp_raise_irq(s);
968     }
969 
970     /*
971      * Always perform the initial transfer upon reception of the next TI
972      * command to ensure the DMA/non-DMA status of the command is correct.
973      * It is not possible to use s->dma directly in the section below as
974      * some OSs send non-DMA NOP commands after a DMA transfer. Hence if the
975      * async data transfer is delayed then s->dma is set incorrectly.
976      */
977 
978     if (s->ti_cmd == (CMD_TI | CMD_DMA)) {
979         /* When the SCSI layer returns more data, raise deferred INTR_BS */
980         esp_dma_ti_check(s);
981 
982         esp_do_dma(s);
983     } else if (s->ti_cmd == CMD_TI) {
984         esp_do_nodma(s);
985     }
986 }
987 
988 static void handle_ti(ESPState *s)
989 {
990     uint32_t dmalen;
991 
992     if (s->dma && !s->dma_enabled) {
993         s->dma_cb = handle_ti;
994         return;
995     }
996 
997     s->ti_cmd = s->rregs[ESP_CMD];
998     if (s->dma) {
999         dmalen = esp_get_tc(s);
1000         trace_esp_handle_ti(dmalen);
1001         esp_do_dma(s);
1002     } else {
1003         trace_esp_handle_ti(s->ti_size);
1004         esp_do_nodma(s);
1005     }
1006 }
1007 
1008 void esp_hard_reset(ESPState *s)
1009 {
1010     memset(s->rregs, 0, ESP_REGS);
1011     memset(s->wregs, 0, ESP_REGS);
1012     s->tchi_written = 0;
1013     s->ti_size = 0;
1014     s->async_len = 0;
1015     fifo8_reset(&s->fifo);
1016     fifo8_reset(&s->cmdfifo);
1017     s->dma = 0;
1018     s->do_cmd = 0;
1019     s->dma_cb = NULL;
1020 
1021     s->rregs[ESP_CFG1] = 7;
1022 }
1023 
1024 static void esp_soft_reset(ESPState *s)
1025 {
1026     qemu_irq_lower(s->irq);
1027     qemu_irq_lower(s->irq_data);
1028     esp_hard_reset(s);
1029 }
1030 
1031 static void esp_bus_reset(ESPState *s)
1032 {
1033     bus_cold_reset(BUS(&s->bus));
1034 }
1035 
1036 static void parent_esp_reset(ESPState *s, int irq, int level)
1037 {
1038     if (level) {
1039         esp_soft_reset(s);
1040     }
1041 }
1042 
1043 static void esp_run_cmd(ESPState *s)
1044 {
1045     uint8_t cmd = s->rregs[ESP_CMD];
1046 
1047     if (cmd & CMD_DMA) {
1048         s->dma = 1;
1049         /* Reload DMA counter.  */
1050         if (esp_get_stc(s) == 0) {
1051             esp_set_tc(s, 0x10000);
1052         } else {
1053             esp_set_tc(s, esp_get_stc(s));
1054         }
1055     } else {
1056         s->dma = 0;
1057     }
1058     switch (cmd & CMD_CMD) {
1059     case CMD_NOP:
1060         trace_esp_mem_writeb_cmd_nop(cmd);
1061         break;
1062     case CMD_FLUSH:
1063         trace_esp_mem_writeb_cmd_flush(cmd);
1064         fifo8_reset(&s->fifo);
1065         break;
1066     case CMD_RESET:
1067         trace_esp_mem_writeb_cmd_reset(cmd);
1068         esp_soft_reset(s);
1069         break;
1070     case CMD_BUSRESET:
1071         trace_esp_mem_writeb_cmd_bus_reset(cmd);
1072         esp_bus_reset(s);
1073         if (!(s->wregs[ESP_CFG1] & CFG1_RESREPT)) {
1074             s->rregs[ESP_RINTR] |= INTR_RST;
1075             esp_raise_irq(s);
1076         }
1077         break;
1078     case CMD_TI:
1079         trace_esp_mem_writeb_cmd_ti(cmd);
1080         handle_ti(s);
1081         break;
1082     case CMD_ICCS:
1083         trace_esp_mem_writeb_cmd_iccs(cmd);
1084         write_response(s);
1085         s->rregs[ESP_RINTR] |= INTR_FC;
1086         esp_set_phase(s, STAT_MI);
1087         break;
1088     case CMD_MSGACC:
1089         trace_esp_mem_writeb_cmd_msgacc(cmd);
1090         s->rregs[ESP_RINTR] |= INTR_DC;
1091         s->rregs[ESP_RSEQ] = 0;
1092         s->rregs[ESP_RFLAGS] = 0;
1093         esp_raise_irq(s);
1094         break;
1095     case CMD_PAD:
1096         trace_esp_mem_writeb_cmd_pad(cmd);
1097         s->rregs[ESP_RSTAT] = STAT_TC;
1098         s->rregs[ESP_RINTR] |= INTR_FC;
1099         s->rregs[ESP_RSEQ] = 0;
1100         break;
1101     case CMD_SATN:
1102         trace_esp_mem_writeb_cmd_satn(cmd);
1103         break;
1104     case CMD_RSTATN:
1105         trace_esp_mem_writeb_cmd_rstatn(cmd);
1106         break;
1107     case CMD_SEL:
1108         trace_esp_mem_writeb_cmd_sel(cmd);
1109         handle_s_without_atn(s);
1110         break;
1111     case CMD_SELATN:
1112         trace_esp_mem_writeb_cmd_selatn(cmd);
1113         handle_satn(s);
1114         break;
1115     case CMD_SELATNS:
1116         trace_esp_mem_writeb_cmd_selatns(cmd);
1117         handle_satn_stop(s);
1118         break;
1119     case CMD_ENSEL:
1120         trace_esp_mem_writeb_cmd_ensel(cmd);
1121         s->rregs[ESP_RINTR] = 0;
1122         break;
1123     case CMD_DISSEL:
1124         trace_esp_mem_writeb_cmd_dissel(cmd);
1125         s->rregs[ESP_RINTR] = 0;
1126         esp_raise_irq(s);
1127         break;
1128     default:
1129         trace_esp_error_unhandled_command(cmd);
1130         break;
1131     }
1132 }
1133 
1134 uint64_t esp_reg_read(ESPState *s, uint32_t saddr)
1135 {
1136     uint32_t val;
1137 
1138     switch (saddr) {
1139     case ESP_FIFO:
1140         if (s->dma_memory_read && s->dma_memory_write &&
1141                 (s->rregs[ESP_RSTAT] & STAT_PIO_MASK) == 0) {
1142             /* Data out.  */
1143             qemu_log_mask(LOG_UNIMP, "esp: PIO data read not implemented\n");
1144             s->rregs[ESP_FIFO] = 0;
1145         } else {
1146             if (esp_get_phase(s) == STAT_DI) {
1147                 if (s->ti_size) {
1148                     esp_do_nodma(s);
1149                 } else {
1150                     /*
1151                      * The last byte of a non-DMA transfer has been read out
1152                      * of the FIFO so switch to status phase
1153                      */
1154                     esp_set_phase(s, STAT_ST);
1155                 }
1156             }
1157             s->rregs[ESP_FIFO] = esp_fifo_pop(&s->fifo);
1158         }
1159         val = s->rregs[ESP_FIFO];
1160         break;
1161     case ESP_RINTR:
1162         /*
1163          * Clear sequence step, interrupt register and all status bits
1164          * except TC
1165          */
1166         val = s->rregs[ESP_RINTR];
1167         s->rregs[ESP_RINTR] = 0;
1168         s->rregs[ESP_RSTAT] &= ~STAT_TC;
1169         /*
1170          * According to the datasheet ESP_RSEQ should be cleared, but as the
1171          * emulation currently defers information transfers to the next TI
1172          * command leave it for now so that pedantic guests such as the old
1173          * Linux 2.6 driver see the correct flags before the next SCSI phase
1174          * transition.
1175          *
1176          * s->rregs[ESP_RSEQ] = SEQ_0;
1177          */
1178         esp_lower_irq(s);
1179         break;
1180     case ESP_TCHI:
1181         /* Return the unique id if the value has never been written */
1182         if (!s->tchi_written) {
1183             val = s->chip_id;
1184         } else {
1185             val = s->rregs[saddr];
1186         }
1187         break;
1188      case ESP_RFLAGS:
1189         /* Bottom 5 bits indicate number of bytes in FIFO */
1190         val = fifo8_num_used(&s->fifo);
1191         break;
1192     default:
1193         val = s->rregs[saddr];
1194         break;
1195     }
1196 
1197     trace_esp_mem_readb(saddr, val);
1198     return val;
1199 }
1200 
1201 void esp_reg_write(ESPState *s, uint32_t saddr, uint64_t val)
1202 {
1203     trace_esp_mem_writeb(saddr, s->wregs[saddr], val);
1204     switch (saddr) {
1205     case ESP_TCHI:
1206         s->tchi_written = true;
1207         /* fall through */
1208     case ESP_TCLO:
1209     case ESP_TCMID:
1210         s->rregs[ESP_RSTAT] &= ~STAT_TC;
1211         break;
1212     case ESP_FIFO:
1213         if (s->do_cmd) {
1214             if (!fifo8_is_full(&s->fifo)) {
1215                 esp_fifo_push(&s->fifo, val);
1216                 esp_fifo_push(&s->cmdfifo, fifo8_pop(&s->fifo));
1217             }
1218 
1219             /*
1220              * If any unexpected message out/command phase data is
1221              * transferred using non-DMA, raise the interrupt
1222              */
1223             if (s->rregs[ESP_CMD] == CMD_TI) {
1224                 s->rregs[ESP_RINTR] |= INTR_BS;
1225                 esp_raise_irq(s);
1226             }
1227         } else {
1228             esp_fifo_push(&s->fifo, val);
1229         }
1230         break;
1231     case ESP_CMD:
1232         s->rregs[saddr] = val;
1233         esp_run_cmd(s);
1234         break;
1235     case ESP_WBUSID ... ESP_WSYNO:
1236         break;
1237     case ESP_CFG1:
1238     case ESP_CFG2: case ESP_CFG3:
1239     case ESP_RES3: case ESP_RES4:
1240         s->rregs[saddr] = val;
1241         break;
1242     case ESP_WCCF ... ESP_WTEST:
1243         break;
1244     default:
1245         trace_esp_error_invalid_write(val, saddr);
1246         return;
1247     }
1248     s->wregs[saddr] = val;
1249 }
1250 
1251 static bool esp_mem_accepts(void *opaque, hwaddr addr,
1252                             unsigned size, bool is_write,
1253                             MemTxAttrs attrs)
1254 {
1255     return (size == 1) || (is_write && size == 4);
1256 }
1257 
1258 static bool esp_is_before_version_5(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 < 5;
1264 }
1265 
1266 static bool esp_is_version_5(void *opaque, int version_id)
1267 {
1268     ESPState *s = ESP(opaque);
1269 
1270     version_id = MIN(version_id, s->mig_version_id);
1271     return version_id >= 5;
1272 }
1273 
1274 static bool esp_is_version_6(void *opaque, int version_id)
1275 {
1276     ESPState *s = ESP(opaque);
1277 
1278     version_id = MIN(version_id, s->mig_version_id);
1279     return version_id >= 6;
1280 }
1281 
1282 int esp_pre_save(void *opaque)
1283 {
1284     ESPState *s = ESP(object_resolve_path_component(
1285                       OBJECT(opaque), "esp"));
1286 
1287     s->mig_version_id = vmstate_esp.version_id;
1288     return 0;
1289 }
1290 
1291 static int esp_post_load(void *opaque, int version_id)
1292 {
1293     ESPState *s = ESP(opaque);
1294     int len, i;
1295 
1296     version_id = MIN(version_id, s->mig_version_id);
1297 
1298     if (version_id < 5) {
1299         esp_set_tc(s, s->mig_dma_left);
1300 
1301         /* Migrate ti_buf to fifo */
1302         len = s->mig_ti_wptr - s->mig_ti_rptr;
1303         for (i = 0; i < len; i++) {
1304             fifo8_push(&s->fifo, s->mig_ti_buf[i]);
1305         }
1306 
1307         /* Migrate cmdbuf to cmdfifo */
1308         for (i = 0; i < s->mig_cmdlen; i++) {
1309             fifo8_push(&s->cmdfifo, s->mig_cmdbuf[i]);
1310         }
1311     }
1312 
1313     s->mig_version_id = vmstate_esp.version_id;
1314     return 0;
1315 }
1316 
1317 /*
1318  * PDMA (or pseudo-DMA) is only used on the Macintosh and requires the
1319  * guest CPU to perform the transfers between the SCSI bus and memory
1320  * itself. This is indicated by the dma_memory_read and dma_memory_write
1321  * functions being NULL (in contrast to the ESP PCI device) whilst
1322  * dma_enabled is still set.
1323  */
1324 
1325 static bool esp_pdma_needed(void *opaque)
1326 {
1327     ESPState *s = ESP(opaque);
1328 
1329     return s->dma_memory_read == NULL && s->dma_memory_write == NULL &&
1330            s->dma_enabled;
1331 }
1332 
1333 static const VMStateDescription vmstate_esp_pdma = {
1334     .name = "esp/pdma",
1335     .version_id = 0,
1336     .minimum_version_id = 0,
1337     .needed = esp_pdma_needed,
1338     .fields = (const VMStateField[]) {
1339         VMSTATE_UINT8(pdma_cb, ESPState),
1340         VMSTATE_END_OF_LIST()
1341     }
1342 };
1343 
1344 const VMStateDescription vmstate_esp = {
1345     .name = "esp",
1346     .version_id = 6,
1347     .minimum_version_id = 3,
1348     .post_load = esp_post_load,
1349     .fields = (const VMStateField[]) {
1350         VMSTATE_BUFFER(rregs, ESPState),
1351         VMSTATE_BUFFER(wregs, ESPState),
1352         VMSTATE_INT32(ti_size, ESPState),
1353         VMSTATE_UINT32_TEST(mig_ti_rptr, ESPState, esp_is_before_version_5),
1354         VMSTATE_UINT32_TEST(mig_ti_wptr, ESPState, esp_is_before_version_5),
1355         VMSTATE_BUFFER_TEST(mig_ti_buf, ESPState, esp_is_before_version_5),
1356         VMSTATE_UINT32(status, ESPState),
1357         VMSTATE_UINT32_TEST(mig_deferred_status, ESPState,
1358                             esp_is_before_version_5),
1359         VMSTATE_BOOL_TEST(mig_deferred_complete, ESPState,
1360                           esp_is_before_version_5),
1361         VMSTATE_UINT32(dma, ESPState),
1362         VMSTATE_STATIC_BUFFER(mig_cmdbuf, ESPState, 0,
1363                               esp_is_before_version_5, 0, 16),
1364         VMSTATE_STATIC_BUFFER(mig_cmdbuf, ESPState, 4,
1365                               esp_is_before_version_5, 16,
1366                               sizeof(typeof_field(ESPState, mig_cmdbuf))),
1367         VMSTATE_UINT32_TEST(mig_cmdlen, ESPState, esp_is_before_version_5),
1368         VMSTATE_UINT32(do_cmd, ESPState),
1369         VMSTATE_UINT32_TEST(mig_dma_left, ESPState, esp_is_before_version_5),
1370         VMSTATE_BOOL_TEST(data_in_ready, ESPState, esp_is_version_5),
1371         VMSTATE_UINT8_TEST(cmdfifo_cdb_offset, ESPState, esp_is_version_5),
1372         VMSTATE_FIFO8_TEST(fifo, ESPState, esp_is_version_5),
1373         VMSTATE_FIFO8_TEST(cmdfifo, ESPState, esp_is_version_5),
1374         VMSTATE_UINT8_TEST(ti_cmd, ESPState, esp_is_version_5),
1375         VMSTATE_UINT8_TEST(lun, ESPState, esp_is_version_6),
1376         VMSTATE_END_OF_LIST()
1377     },
1378     .subsections = (const VMStateDescription * const []) {
1379         &vmstate_esp_pdma,
1380         NULL
1381     }
1382 };
1383 
1384 static void sysbus_esp_mem_write(void *opaque, hwaddr addr,
1385                                  uint64_t val, unsigned int size)
1386 {
1387     SysBusESPState *sysbus = opaque;
1388     ESPState *s = ESP(&sysbus->esp);
1389     uint32_t saddr;
1390 
1391     saddr = addr >> sysbus->it_shift;
1392     esp_reg_write(s, saddr, val);
1393 }
1394 
1395 static uint64_t sysbus_esp_mem_read(void *opaque, hwaddr addr,
1396                                     unsigned int size)
1397 {
1398     SysBusESPState *sysbus = opaque;
1399     ESPState *s = ESP(&sysbus->esp);
1400     uint32_t saddr;
1401 
1402     saddr = addr >> sysbus->it_shift;
1403     return esp_reg_read(s, saddr);
1404 }
1405 
1406 static const MemoryRegionOps sysbus_esp_mem_ops = {
1407     .read = sysbus_esp_mem_read,
1408     .write = sysbus_esp_mem_write,
1409     .endianness = DEVICE_NATIVE_ENDIAN,
1410     .valid.accepts = esp_mem_accepts,
1411 };
1412 
1413 static void sysbus_esp_pdma_write(void *opaque, hwaddr addr,
1414                                   uint64_t val, unsigned int size)
1415 {
1416     SysBusESPState *sysbus = opaque;
1417     ESPState *s = ESP(&sysbus->esp);
1418 
1419     trace_esp_pdma_write(size);
1420 
1421     switch (size) {
1422     case 1:
1423         esp_pdma_write(s, val);
1424         break;
1425     case 2:
1426         esp_pdma_write(s, val >> 8);
1427         esp_pdma_write(s, val);
1428         break;
1429     }
1430     esp_pdma_cb(s);
1431 }
1432 
1433 static uint64_t sysbus_esp_pdma_read(void *opaque, hwaddr addr,
1434                                      unsigned int size)
1435 {
1436     SysBusESPState *sysbus = opaque;
1437     ESPState *s = ESP(&sysbus->esp);
1438     uint64_t val = 0;
1439 
1440     trace_esp_pdma_read(size);
1441 
1442     switch (size) {
1443     case 1:
1444         val = esp_pdma_read(s);
1445         break;
1446     case 2:
1447         val = esp_pdma_read(s);
1448         val = (val << 8) | esp_pdma_read(s);
1449         break;
1450     }
1451     esp_pdma_cb(s);
1452     return val;
1453 }
1454 
1455 static void *esp_load_request(QEMUFile *f, SCSIRequest *req)
1456 {
1457     ESPState *s = container_of(req->bus, ESPState, bus);
1458 
1459     scsi_req_ref(req);
1460     s->current_req = req;
1461     return s;
1462 }
1463 
1464 static const MemoryRegionOps sysbus_esp_pdma_ops = {
1465     .read = sysbus_esp_pdma_read,
1466     .write = sysbus_esp_pdma_write,
1467     .endianness = DEVICE_NATIVE_ENDIAN,
1468     .valid.min_access_size = 1,
1469     .valid.max_access_size = 4,
1470     .impl.min_access_size = 1,
1471     .impl.max_access_size = 2,
1472 };
1473 
1474 static const struct SCSIBusInfo esp_scsi_info = {
1475     .tcq = false,
1476     .max_target = ESP_MAX_DEVS,
1477     .max_lun = 7,
1478 
1479     .load_request = esp_load_request,
1480     .transfer_data = esp_transfer_data,
1481     .complete = esp_command_complete,
1482     .cancel = esp_request_cancelled
1483 };
1484 
1485 static void sysbus_esp_gpio_demux(void *opaque, int irq, int level)
1486 {
1487     SysBusESPState *sysbus = SYSBUS_ESP(opaque);
1488     ESPState *s = ESP(&sysbus->esp);
1489 
1490     switch (irq) {
1491     case 0:
1492         parent_esp_reset(s, irq, level);
1493         break;
1494     case 1:
1495         esp_dma_enable(s, irq, level);
1496         break;
1497     }
1498 }
1499 
1500 static void sysbus_esp_realize(DeviceState *dev, Error **errp)
1501 {
1502     SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
1503     SysBusESPState *sysbus = SYSBUS_ESP(dev);
1504     ESPState *s = ESP(&sysbus->esp);
1505 
1506     if (!qdev_realize(DEVICE(s), NULL, errp)) {
1507         return;
1508     }
1509 
1510     sysbus_init_irq(sbd, &s->irq);
1511     sysbus_init_irq(sbd, &s->irq_data);
1512     assert(sysbus->it_shift != -1);
1513 
1514     s->chip_id = TCHI_FAS100A;
1515     memory_region_init_io(&sysbus->iomem, OBJECT(sysbus), &sysbus_esp_mem_ops,
1516                           sysbus, "esp-regs", ESP_REGS << sysbus->it_shift);
1517     sysbus_init_mmio(sbd, &sysbus->iomem);
1518     memory_region_init_io(&sysbus->pdma, OBJECT(sysbus), &sysbus_esp_pdma_ops,
1519                           sysbus, "esp-pdma", 4);
1520     sysbus_init_mmio(sbd, &sysbus->pdma);
1521 
1522     qdev_init_gpio_in(dev, sysbus_esp_gpio_demux, 2);
1523 
1524     scsi_bus_init(&s->bus, sizeof(s->bus), dev, &esp_scsi_info);
1525 }
1526 
1527 static void sysbus_esp_hard_reset(DeviceState *dev)
1528 {
1529     SysBusESPState *sysbus = SYSBUS_ESP(dev);
1530     ESPState *s = ESP(&sysbus->esp);
1531 
1532     esp_hard_reset(s);
1533 }
1534 
1535 static void sysbus_esp_init(Object *obj)
1536 {
1537     SysBusESPState *sysbus = SYSBUS_ESP(obj);
1538 
1539     object_initialize_child(obj, "esp", &sysbus->esp, TYPE_ESP);
1540 }
1541 
1542 static const VMStateDescription vmstate_sysbus_esp_scsi = {
1543     .name = "sysbusespscsi",
1544     .version_id = 2,
1545     .minimum_version_id = 1,
1546     .pre_save = esp_pre_save,
1547     .fields = (const VMStateField[]) {
1548         VMSTATE_UINT8_V(esp.mig_version_id, SysBusESPState, 2),
1549         VMSTATE_STRUCT(esp, SysBusESPState, 0, vmstate_esp, ESPState),
1550         VMSTATE_END_OF_LIST()
1551     }
1552 };
1553 
1554 static void sysbus_esp_class_init(ObjectClass *klass, void *data)
1555 {
1556     DeviceClass *dc = DEVICE_CLASS(klass);
1557 
1558     dc->realize = sysbus_esp_realize;
1559     dc->reset = sysbus_esp_hard_reset;
1560     dc->vmsd = &vmstate_sysbus_esp_scsi;
1561     set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
1562 }
1563 
1564 static const TypeInfo sysbus_esp_info = {
1565     .name          = TYPE_SYSBUS_ESP,
1566     .parent        = TYPE_SYS_BUS_DEVICE,
1567     .instance_init = sysbus_esp_init,
1568     .instance_size = sizeof(SysBusESPState),
1569     .class_init    = sysbus_esp_class_init,
1570 };
1571 
1572 static void esp_finalize(Object *obj)
1573 {
1574     ESPState *s = ESP(obj);
1575 
1576     fifo8_destroy(&s->fifo);
1577     fifo8_destroy(&s->cmdfifo);
1578 }
1579 
1580 static void esp_init(Object *obj)
1581 {
1582     ESPState *s = ESP(obj);
1583 
1584     fifo8_create(&s->fifo, ESP_FIFO_SZ);
1585     fifo8_create(&s->cmdfifo, ESP_CMDFIFO_SZ);
1586 }
1587 
1588 static void esp_class_init(ObjectClass *klass, void *data)
1589 {
1590     DeviceClass *dc = DEVICE_CLASS(klass);
1591 
1592     /* internal device for sysbusesp/pciespscsi, not user-creatable */
1593     dc->user_creatable = false;
1594     set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
1595 }
1596 
1597 static const TypeInfo esp_info = {
1598     .name = TYPE_ESP,
1599     .parent = TYPE_DEVICE,
1600     .instance_init = esp_init,
1601     .instance_finalize = esp_finalize,
1602     .instance_size = sizeof(ESPState),
1603     .class_init = esp_class_init,
1604 };
1605 
1606 static void esp_register_types(void)
1607 {
1608     type_register_static(&sysbus_esp_info);
1609     type_register_static(&esp_info);
1610 }
1611 
1612 type_init(esp_register_types)
1613