xref: /qemu/hw/scsi/esp.c (revision 844b3a84eaa3ae92e5c178cd985506f94756ad86)
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     int to_device = (esp_get_phase(s) == STAT_DO);
790     uint8_t buf[ESP_FIFO_SZ];
791     uint32_t cmdlen;
792     int len, n;
793 
794     if (s->do_cmd) {
795         /* Copy FIFO into cmdfifo */
796         n = esp_fifo_pop_buf(&s->fifo, buf, fifo8_num_used(&s->fifo));
797         n = MIN(fifo8_num_free(&s->cmdfifo), n);
798         fifo8_push_all(&s->cmdfifo, buf, n);
799 
800         cmdlen = fifo8_num_used(&s->cmdfifo);
801         trace_esp_handle_ti_cmd(cmdlen);
802         s->ti_size = 0;
803         if (esp_get_phase(s) == STAT_CD) {
804             /* No command received */
805             if (s->cmdfifo_cdb_offset == fifo8_num_used(&s->cmdfifo)) {
806                 return;
807             }
808 
809             /* Command has been received */
810             s->do_cmd = 0;
811             do_cmd(s);
812         } else {
813             /*
814              * Extra message out bytes received: update cmdfifo_cdb_offset
815              * and then switch to command phase
816              */
817             s->cmdfifo_cdb_offset = fifo8_num_used(&s->cmdfifo);
818             esp_set_phase(s, STAT_CD);
819             s->rregs[ESP_RSEQ] = SEQ_CD;
820             s->rregs[ESP_RINTR] |= INTR_BS;
821             esp_raise_irq(s);
822         }
823         return;
824     }
825 
826     if (!s->current_req) {
827         return;
828     }
829 
830     if (s->async_len == 0) {
831         /* Defer until data is available.  */
832         return;
833     }
834 
835     if (to_device) {
836         len = MIN(s->async_len, ESP_FIFO_SZ);
837         len = MIN(len, fifo8_num_used(&s->fifo));
838         esp_fifo_pop_buf(&s->fifo, s->async_buf, len);
839         s->async_buf += len;
840         s->async_len -= len;
841         s->ti_size += len;
842     } else {
843         if (fifo8_is_empty(&s->fifo)) {
844             fifo8_push(&s->fifo, s->async_buf[0]);
845             s->async_buf++;
846             s->async_len--;
847             s->ti_size--;
848         }
849     }
850 
851     if (s->async_len == 0) {
852         scsi_req_continue(s->current_req);
853         return;
854     }
855 
856     s->rregs[ESP_RINTR] |= INTR_BS;
857     esp_raise_irq(s);
858 }
859 
860 static void esp_pdma_cb(ESPState *s)
861 {
862     switch (s->pdma_cb) {
863     case SATN_PDMA_CB:
864         satn_pdma_cb(s);
865         break;
866     case SATN_STOP_PDMA_CB:
867         satn_stop_pdma_cb(s);
868         break;
869     case WRITE_RESPONSE_PDMA_CB:
870         write_response_pdma_cb(s);
871         break;
872     case DO_DMA_PDMA_CB:
873         do_dma_pdma_cb(s);
874         break;
875     default:
876         g_assert_not_reached();
877     }
878 }
879 
880 void esp_command_complete(SCSIRequest *req, size_t resid)
881 {
882     ESPState *s = req->hba_private;
883     int to_device = (esp_get_phase(s) == STAT_DO);
884 
885     trace_esp_command_complete();
886 
887     /*
888      * Non-DMA transfers from the target will leave the last byte in
889      * the FIFO so don't reset ti_size in this case
890      */
891     if (s->dma || to_device) {
892         if (s->ti_size != 0) {
893             trace_esp_command_complete_unexpected();
894         }
895     }
896 
897     s->async_len = 0;
898     if (req->status) {
899         trace_esp_command_complete_fail();
900     }
901     s->status = req->status;
902 
903     /*
904      * Switch to status phase. For non-DMA transfers from the target the last
905      * byte is still in the FIFO
906      */
907     esp_set_phase(s, STAT_ST);
908     if (s->ti_size == 0) {
909         /*
910          * Transfer complete: force TC to zero just in case a TI command was
911          * requested for more data than the command returns (Solaris 8 does
912          * this)
913          */
914         esp_set_tc(s, 0);
915         esp_dma_ti_check(s);
916     } else {
917         /*
918          * Transfer truncated: raise INTR_BS to indicate early change of
919          * phase
920          */
921         s->rregs[ESP_RINTR] |= INTR_BS;
922         esp_raise_irq(s);
923         s->ti_size = 0;
924     }
925 
926     if (s->current_req) {
927         scsi_req_unref(s->current_req);
928         s->current_req = NULL;
929         s->current_dev = NULL;
930     }
931 }
932 
933 void esp_transfer_data(SCSIRequest *req, uint32_t len)
934 {
935     ESPState *s = req->hba_private;
936     int to_device = (esp_get_phase(s) == STAT_DO);
937     uint32_t dmalen = esp_get_tc(s);
938 
939     assert(!s->do_cmd);
940     trace_esp_transfer_data(dmalen, s->ti_size);
941     s->async_len = len;
942     s->async_buf = scsi_req_get_buf(req);
943 
944     if (!to_device && !s->data_in_ready) {
945         /*
946          * Initial incoming data xfer is complete so raise command
947          * completion interrupt
948          */
949         s->data_in_ready = true;
950         s->rregs[ESP_RINTR] |= INTR_BS;
951         esp_raise_irq(s);
952     }
953 
954     /*
955      * Always perform the initial transfer upon reception of the next TI
956      * command to ensure the DMA/non-DMA status of the command is correct.
957      * It is not possible to use s->dma directly in the section below as
958      * some OSs send non-DMA NOP commands after a DMA transfer. Hence if the
959      * async data transfer is delayed then s->dma is set incorrectly.
960      */
961 
962     if (s->ti_cmd == (CMD_TI | CMD_DMA)) {
963         /* When the SCSI layer returns more data, raise deferred INTR_BS */
964         esp_dma_ti_check(s);
965 
966         esp_do_dma(s);
967     } else if (s->ti_cmd == CMD_TI) {
968         esp_do_nodma(s);
969     }
970 }
971 
972 static void handle_ti(ESPState *s)
973 {
974     uint32_t dmalen;
975 
976     if (s->dma && !s->dma_enabled) {
977         s->dma_cb = handle_ti;
978         return;
979     }
980 
981     s->ti_cmd = s->rregs[ESP_CMD];
982     if (s->dma) {
983         dmalen = esp_get_tc(s);
984         trace_esp_handle_ti(dmalen);
985         esp_do_dma(s);
986     } else {
987         trace_esp_handle_ti(s->ti_size);
988         esp_do_nodma(s);
989     }
990 }
991 
992 void esp_hard_reset(ESPState *s)
993 {
994     memset(s->rregs, 0, ESP_REGS);
995     memset(s->wregs, 0, ESP_REGS);
996     s->tchi_written = 0;
997     s->ti_size = 0;
998     s->async_len = 0;
999     fifo8_reset(&s->fifo);
1000     fifo8_reset(&s->cmdfifo);
1001     s->dma = 0;
1002     s->do_cmd = 0;
1003     s->dma_cb = NULL;
1004 
1005     s->rregs[ESP_CFG1] = 7;
1006 }
1007 
1008 static void esp_soft_reset(ESPState *s)
1009 {
1010     qemu_irq_lower(s->irq);
1011     qemu_irq_lower(s->irq_data);
1012     esp_hard_reset(s);
1013 }
1014 
1015 static void esp_bus_reset(ESPState *s)
1016 {
1017     bus_cold_reset(BUS(&s->bus));
1018 }
1019 
1020 static void parent_esp_reset(ESPState *s, int irq, int level)
1021 {
1022     if (level) {
1023         esp_soft_reset(s);
1024     }
1025 }
1026 
1027 static void esp_run_cmd(ESPState *s)
1028 {
1029     uint8_t cmd = s->rregs[ESP_CMD];
1030 
1031     if (cmd & CMD_DMA) {
1032         s->dma = 1;
1033         /* Reload DMA counter.  */
1034         if (esp_get_stc(s) == 0) {
1035             esp_set_tc(s, 0x10000);
1036         } else {
1037             esp_set_tc(s, esp_get_stc(s));
1038         }
1039     } else {
1040         s->dma = 0;
1041     }
1042     switch (cmd & CMD_CMD) {
1043     case CMD_NOP:
1044         trace_esp_mem_writeb_cmd_nop(cmd);
1045         break;
1046     case CMD_FLUSH:
1047         trace_esp_mem_writeb_cmd_flush(cmd);
1048         fifo8_reset(&s->fifo);
1049         break;
1050     case CMD_RESET:
1051         trace_esp_mem_writeb_cmd_reset(cmd);
1052         esp_soft_reset(s);
1053         break;
1054     case CMD_BUSRESET:
1055         trace_esp_mem_writeb_cmd_bus_reset(cmd);
1056         esp_bus_reset(s);
1057         if (!(s->wregs[ESP_CFG1] & CFG1_RESREPT)) {
1058             s->rregs[ESP_RINTR] |= INTR_RST;
1059             esp_raise_irq(s);
1060         }
1061         break;
1062     case CMD_TI:
1063         trace_esp_mem_writeb_cmd_ti(cmd);
1064         handle_ti(s);
1065         break;
1066     case CMD_ICCS:
1067         trace_esp_mem_writeb_cmd_iccs(cmd);
1068         write_response(s);
1069         s->rregs[ESP_RINTR] |= INTR_FC;
1070         esp_set_phase(s, STAT_MI);
1071         break;
1072     case CMD_MSGACC:
1073         trace_esp_mem_writeb_cmd_msgacc(cmd);
1074         s->rregs[ESP_RINTR] |= INTR_DC;
1075         s->rregs[ESP_RSEQ] = 0;
1076         s->rregs[ESP_RFLAGS] = 0;
1077         esp_raise_irq(s);
1078         break;
1079     case CMD_PAD:
1080         trace_esp_mem_writeb_cmd_pad(cmd);
1081         s->rregs[ESP_RSTAT] = STAT_TC;
1082         s->rregs[ESP_RINTR] |= INTR_FC;
1083         s->rregs[ESP_RSEQ] = 0;
1084         break;
1085     case CMD_SATN:
1086         trace_esp_mem_writeb_cmd_satn(cmd);
1087         break;
1088     case CMD_RSTATN:
1089         trace_esp_mem_writeb_cmd_rstatn(cmd);
1090         break;
1091     case CMD_SEL:
1092         trace_esp_mem_writeb_cmd_sel(cmd);
1093         handle_s_without_atn(s);
1094         break;
1095     case CMD_SELATN:
1096         trace_esp_mem_writeb_cmd_selatn(cmd);
1097         handle_satn(s);
1098         break;
1099     case CMD_SELATNS:
1100         trace_esp_mem_writeb_cmd_selatns(cmd);
1101         handle_satn_stop(s);
1102         break;
1103     case CMD_ENSEL:
1104         trace_esp_mem_writeb_cmd_ensel(cmd);
1105         s->rregs[ESP_RINTR] = 0;
1106         break;
1107     case CMD_DISSEL:
1108         trace_esp_mem_writeb_cmd_dissel(cmd);
1109         s->rregs[ESP_RINTR] = 0;
1110         esp_raise_irq(s);
1111         break;
1112     default:
1113         trace_esp_error_unhandled_command(cmd);
1114         break;
1115     }
1116 }
1117 
1118 uint64_t esp_reg_read(ESPState *s, uint32_t saddr)
1119 {
1120     uint32_t val;
1121 
1122     switch (saddr) {
1123     case ESP_FIFO:
1124         if (s->dma_memory_read && s->dma_memory_write &&
1125                 (s->rregs[ESP_RSTAT] & STAT_PIO_MASK) == 0) {
1126             /* Data out.  */
1127             qemu_log_mask(LOG_UNIMP, "esp: PIO data read not implemented\n");
1128             s->rregs[ESP_FIFO] = 0;
1129         } else {
1130             if (esp_get_phase(s) == STAT_DI) {
1131                 if (s->ti_size) {
1132                     esp_do_nodma(s);
1133                 } else {
1134                     /*
1135                      * The last byte of a non-DMA transfer has been read out
1136                      * of the FIFO so switch to status phase
1137                      */
1138                     esp_set_phase(s, STAT_ST);
1139                 }
1140             }
1141             s->rregs[ESP_FIFO] = esp_fifo_pop(&s->fifo);
1142         }
1143         val = s->rregs[ESP_FIFO];
1144         break;
1145     case ESP_RINTR:
1146         /*
1147          * Clear sequence step, interrupt register and all status bits
1148          * except TC
1149          */
1150         val = s->rregs[ESP_RINTR];
1151         s->rregs[ESP_RINTR] = 0;
1152         s->rregs[ESP_RSTAT] &= ~STAT_TC;
1153         /*
1154          * According to the datasheet ESP_RSEQ should be cleared, but as the
1155          * emulation currently defers information transfers to the next TI
1156          * command leave it for now so that pedantic guests such as the old
1157          * Linux 2.6 driver see the correct flags before the next SCSI phase
1158          * transition.
1159          *
1160          * s->rregs[ESP_RSEQ] = SEQ_0;
1161          */
1162         esp_lower_irq(s);
1163         break;
1164     case ESP_TCHI:
1165         /* Return the unique id if the value has never been written */
1166         if (!s->tchi_written) {
1167             val = s->chip_id;
1168         } else {
1169             val = s->rregs[saddr];
1170         }
1171         break;
1172      case ESP_RFLAGS:
1173         /* Bottom 5 bits indicate number of bytes in FIFO */
1174         val = fifo8_num_used(&s->fifo);
1175         break;
1176     default:
1177         val = s->rregs[saddr];
1178         break;
1179     }
1180 
1181     trace_esp_mem_readb(saddr, val);
1182     return val;
1183 }
1184 
1185 void esp_reg_write(ESPState *s, uint32_t saddr, uint64_t val)
1186 {
1187     trace_esp_mem_writeb(saddr, s->wregs[saddr], val);
1188     switch (saddr) {
1189     case ESP_TCHI:
1190         s->tchi_written = true;
1191         /* fall through */
1192     case ESP_TCLO:
1193     case ESP_TCMID:
1194         s->rregs[ESP_RSTAT] &= ~STAT_TC;
1195         break;
1196     case ESP_FIFO:
1197         if (s->do_cmd) {
1198             if (!fifo8_is_full(&s->fifo)) {
1199                 esp_fifo_push(&s->fifo, val);
1200                 esp_fifo_push(&s->cmdfifo, fifo8_pop(&s->fifo));
1201             }
1202 
1203             /*
1204              * If any unexpected message out/command phase data is
1205              * transferred using non-DMA, raise the interrupt
1206              */
1207             if (s->rregs[ESP_CMD] == CMD_TI) {
1208                 s->rregs[ESP_RINTR] |= INTR_BS;
1209                 esp_raise_irq(s);
1210             }
1211         } else {
1212             esp_fifo_push(&s->fifo, val);
1213         }
1214         break;
1215     case ESP_CMD:
1216         s->rregs[saddr] = val;
1217         esp_run_cmd(s);
1218         break;
1219     case ESP_WBUSID ... ESP_WSYNO:
1220         break;
1221     case ESP_CFG1:
1222     case ESP_CFG2: case ESP_CFG3:
1223     case ESP_RES3: case ESP_RES4:
1224         s->rregs[saddr] = val;
1225         break;
1226     case ESP_WCCF ... ESP_WTEST:
1227         break;
1228     default:
1229         trace_esp_error_invalid_write(val, saddr);
1230         return;
1231     }
1232     s->wregs[saddr] = val;
1233 }
1234 
1235 static bool esp_mem_accepts(void *opaque, hwaddr addr,
1236                             unsigned size, bool is_write,
1237                             MemTxAttrs attrs)
1238 {
1239     return (size == 1) || (is_write && size == 4);
1240 }
1241 
1242 static bool esp_is_before_version_5(void *opaque, int version_id)
1243 {
1244     ESPState *s = ESP(opaque);
1245 
1246     version_id = MIN(version_id, s->mig_version_id);
1247     return version_id < 5;
1248 }
1249 
1250 static bool esp_is_version_5(void *opaque, int version_id)
1251 {
1252     ESPState *s = ESP(opaque);
1253 
1254     version_id = MIN(version_id, s->mig_version_id);
1255     return version_id >= 5;
1256 }
1257 
1258 static bool esp_is_version_6(void *opaque, int version_id)
1259 {
1260     ESPState *s = ESP(opaque);
1261 
1262     version_id = MIN(version_id, s->mig_version_id);
1263     return version_id >= 6;
1264 }
1265 
1266 int esp_pre_save(void *opaque)
1267 {
1268     ESPState *s = ESP(object_resolve_path_component(
1269                       OBJECT(opaque), "esp"));
1270 
1271     s->mig_version_id = vmstate_esp.version_id;
1272     return 0;
1273 }
1274 
1275 static int esp_post_load(void *opaque, int version_id)
1276 {
1277     ESPState *s = ESP(opaque);
1278     int len, i;
1279 
1280     version_id = MIN(version_id, s->mig_version_id);
1281 
1282     if (version_id < 5) {
1283         esp_set_tc(s, s->mig_dma_left);
1284 
1285         /* Migrate ti_buf to fifo */
1286         len = s->mig_ti_wptr - s->mig_ti_rptr;
1287         for (i = 0; i < len; i++) {
1288             fifo8_push(&s->fifo, s->mig_ti_buf[i]);
1289         }
1290 
1291         /* Migrate cmdbuf to cmdfifo */
1292         for (i = 0; i < s->mig_cmdlen; i++) {
1293             fifo8_push(&s->cmdfifo, s->mig_cmdbuf[i]);
1294         }
1295     }
1296 
1297     s->mig_version_id = vmstate_esp.version_id;
1298     return 0;
1299 }
1300 
1301 /*
1302  * PDMA (or pseudo-DMA) is only used on the Macintosh and requires the
1303  * guest CPU to perform the transfers between the SCSI bus and memory
1304  * itself. This is indicated by the dma_memory_read and dma_memory_write
1305  * functions being NULL (in contrast to the ESP PCI device) whilst
1306  * dma_enabled is still set.
1307  */
1308 
1309 static bool esp_pdma_needed(void *opaque)
1310 {
1311     ESPState *s = ESP(opaque);
1312 
1313     return s->dma_memory_read == NULL && s->dma_memory_write == NULL &&
1314            s->dma_enabled;
1315 }
1316 
1317 static const VMStateDescription vmstate_esp_pdma = {
1318     .name = "esp/pdma",
1319     .version_id = 0,
1320     .minimum_version_id = 0,
1321     .needed = esp_pdma_needed,
1322     .fields = (const VMStateField[]) {
1323         VMSTATE_UINT8(pdma_cb, ESPState),
1324         VMSTATE_END_OF_LIST()
1325     }
1326 };
1327 
1328 const VMStateDescription vmstate_esp = {
1329     .name = "esp",
1330     .version_id = 6,
1331     .minimum_version_id = 3,
1332     .post_load = esp_post_load,
1333     .fields = (const VMStateField[]) {
1334         VMSTATE_BUFFER(rregs, ESPState),
1335         VMSTATE_BUFFER(wregs, ESPState),
1336         VMSTATE_INT32(ti_size, ESPState),
1337         VMSTATE_UINT32_TEST(mig_ti_rptr, ESPState, esp_is_before_version_5),
1338         VMSTATE_UINT32_TEST(mig_ti_wptr, ESPState, esp_is_before_version_5),
1339         VMSTATE_BUFFER_TEST(mig_ti_buf, ESPState, esp_is_before_version_5),
1340         VMSTATE_UINT32(status, ESPState),
1341         VMSTATE_UINT32_TEST(mig_deferred_status, ESPState,
1342                             esp_is_before_version_5),
1343         VMSTATE_BOOL_TEST(mig_deferred_complete, ESPState,
1344                           esp_is_before_version_5),
1345         VMSTATE_UINT32(dma, ESPState),
1346         VMSTATE_STATIC_BUFFER(mig_cmdbuf, ESPState, 0,
1347                               esp_is_before_version_5, 0, 16),
1348         VMSTATE_STATIC_BUFFER(mig_cmdbuf, ESPState, 4,
1349                               esp_is_before_version_5, 16,
1350                               sizeof(typeof_field(ESPState, mig_cmdbuf))),
1351         VMSTATE_UINT32_TEST(mig_cmdlen, ESPState, esp_is_before_version_5),
1352         VMSTATE_UINT32(do_cmd, ESPState),
1353         VMSTATE_UINT32_TEST(mig_dma_left, ESPState, esp_is_before_version_5),
1354         VMSTATE_BOOL_TEST(data_in_ready, ESPState, esp_is_version_5),
1355         VMSTATE_UINT8_TEST(cmdfifo_cdb_offset, ESPState, esp_is_version_5),
1356         VMSTATE_FIFO8_TEST(fifo, ESPState, esp_is_version_5),
1357         VMSTATE_FIFO8_TEST(cmdfifo, ESPState, esp_is_version_5),
1358         VMSTATE_UINT8_TEST(ti_cmd, ESPState, esp_is_version_5),
1359         VMSTATE_UINT8_TEST(lun, ESPState, esp_is_version_6),
1360         VMSTATE_END_OF_LIST()
1361     },
1362     .subsections = (const VMStateDescription * const []) {
1363         &vmstate_esp_pdma,
1364         NULL
1365     }
1366 };
1367 
1368 static void sysbus_esp_mem_write(void *opaque, hwaddr addr,
1369                                  uint64_t val, unsigned int size)
1370 {
1371     SysBusESPState *sysbus = opaque;
1372     ESPState *s = ESP(&sysbus->esp);
1373     uint32_t saddr;
1374 
1375     saddr = addr >> sysbus->it_shift;
1376     esp_reg_write(s, saddr, val);
1377 }
1378 
1379 static uint64_t sysbus_esp_mem_read(void *opaque, hwaddr addr,
1380                                     unsigned int size)
1381 {
1382     SysBusESPState *sysbus = opaque;
1383     ESPState *s = ESP(&sysbus->esp);
1384     uint32_t saddr;
1385 
1386     saddr = addr >> sysbus->it_shift;
1387     return esp_reg_read(s, saddr);
1388 }
1389 
1390 static const MemoryRegionOps sysbus_esp_mem_ops = {
1391     .read = sysbus_esp_mem_read,
1392     .write = sysbus_esp_mem_write,
1393     .endianness = DEVICE_NATIVE_ENDIAN,
1394     .valid.accepts = esp_mem_accepts,
1395 };
1396 
1397 static void sysbus_esp_pdma_write(void *opaque, hwaddr addr,
1398                                   uint64_t val, unsigned int size)
1399 {
1400     SysBusESPState *sysbus = opaque;
1401     ESPState *s = ESP(&sysbus->esp);
1402 
1403     trace_esp_pdma_write(size);
1404 
1405     switch (size) {
1406     case 1:
1407         esp_pdma_write(s, val);
1408         break;
1409     case 2:
1410         esp_pdma_write(s, val >> 8);
1411         esp_pdma_write(s, val);
1412         break;
1413     }
1414     esp_pdma_cb(s);
1415 }
1416 
1417 static uint64_t sysbus_esp_pdma_read(void *opaque, hwaddr addr,
1418                                      unsigned int size)
1419 {
1420     SysBusESPState *sysbus = opaque;
1421     ESPState *s = ESP(&sysbus->esp);
1422     uint64_t val = 0;
1423 
1424     trace_esp_pdma_read(size);
1425 
1426     switch (size) {
1427     case 1:
1428         val = esp_pdma_read(s);
1429         break;
1430     case 2:
1431         val = esp_pdma_read(s);
1432         val = (val << 8) | esp_pdma_read(s);
1433         break;
1434     }
1435     esp_pdma_cb(s);
1436     return val;
1437 }
1438 
1439 static void *esp_load_request(QEMUFile *f, SCSIRequest *req)
1440 {
1441     ESPState *s = container_of(req->bus, ESPState, bus);
1442 
1443     scsi_req_ref(req);
1444     s->current_req = req;
1445     return s;
1446 }
1447 
1448 static const MemoryRegionOps sysbus_esp_pdma_ops = {
1449     .read = sysbus_esp_pdma_read,
1450     .write = sysbus_esp_pdma_write,
1451     .endianness = DEVICE_NATIVE_ENDIAN,
1452     .valid.min_access_size = 1,
1453     .valid.max_access_size = 4,
1454     .impl.min_access_size = 1,
1455     .impl.max_access_size = 2,
1456 };
1457 
1458 static const struct SCSIBusInfo esp_scsi_info = {
1459     .tcq = false,
1460     .max_target = ESP_MAX_DEVS,
1461     .max_lun = 7,
1462 
1463     .load_request = esp_load_request,
1464     .transfer_data = esp_transfer_data,
1465     .complete = esp_command_complete,
1466     .cancel = esp_request_cancelled
1467 };
1468 
1469 static void sysbus_esp_gpio_demux(void *opaque, int irq, int level)
1470 {
1471     SysBusESPState *sysbus = SYSBUS_ESP(opaque);
1472     ESPState *s = ESP(&sysbus->esp);
1473 
1474     switch (irq) {
1475     case 0:
1476         parent_esp_reset(s, irq, level);
1477         break;
1478     case 1:
1479         esp_dma_enable(s, irq, level);
1480         break;
1481     }
1482 }
1483 
1484 static void sysbus_esp_realize(DeviceState *dev, Error **errp)
1485 {
1486     SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
1487     SysBusESPState *sysbus = SYSBUS_ESP(dev);
1488     ESPState *s = ESP(&sysbus->esp);
1489 
1490     if (!qdev_realize(DEVICE(s), NULL, errp)) {
1491         return;
1492     }
1493 
1494     sysbus_init_irq(sbd, &s->irq);
1495     sysbus_init_irq(sbd, &s->irq_data);
1496     assert(sysbus->it_shift != -1);
1497 
1498     s->chip_id = TCHI_FAS100A;
1499     memory_region_init_io(&sysbus->iomem, OBJECT(sysbus), &sysbus_esp_mem_ops,
1500                           sysbus, "esp-regs", ESP_REGS << sysbus->it_shift);
1501     sysbus_init_mmio(sbd, &sysbus->iomem);
1502     memory_region_init_io(&sysbus->pdma, OBJECT(sysbus), &sysbus_esp_pdma_ops,
1503                           sysbus, "esp-pdma", 4);
1504     sysbus_init_mmio(sbd, &sysbus->pdma);
1505 
1506     qdev_init_gpio_in(dev, sysbus_esp_gpio_demux, 2);
1507 
1508     scsi_bus_init(&s->bus, sizeof(s->bus), dev, &esp_scsi_info);
1509 }
1510 
1511 static void sysbus_esp_hard_reset(DeviceState *dev)
1512 {
1513     SysBusESPState *sysbus = SYSBUS_ESP(dev);
1514     ESPState *s = ESP(&sysbus->esp);
1515 
1516     esp_hard_reset(s);
1517 }
1518 
1519 static void sysbus_esp_init(Object *obj)
1520 {
1521     SysBusESPState *sysbus = SYSBUS_ESP(obj);
1522 
1523     object_initialize_child(obj, "esp", &sysbus->esp, TYPE_ESP);
1524 }
1525 
1526 static const VMStateDescription vmstate_sysbus_esp_scsi = {
1527     .name = "sysbusespscsi",
1528     .version_id = 2,
1529     .minimum_version_id = 1,
1530     .pre_save = esp_pre_save,
1531     .fields = (const VMStateField[]) {
1532         VMSTATE_UINT8_V(esp.mig_version_id, SysBusESPState, 2),
1533         VMSTATE_STRUCT(esp, SysBusESPState, 0, vmstate_esp, ESPState),
1534         VMSTATE_END_OF_LIST()
1535     }
1536 };
1537 
1538 static void sysbus_esp_class_init(ObjectClass *klass, void *data)
1539 {
1540     DeviceClass *dc = DEVICE_CLASS(klass);
1541 
1542     dc->realize = sysbus_esp_realize;
1543     dc->reset = sysbus_esp_hard_reset;
1544     dc->vmsd = &vmstate_sysbus_esp_scsi;
1545     set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
1546 }
1547 
1548 static const TypeInfo sysbus_esp_info = {
1549     .name          = TYPE_SYSBUS_ESP,
1550     .parent        = TYPE_SYS_BUS_DEVICE,
1551     .instance_init = sysbus_esp_init,
1552     .instance_size = sizeof(SysBusESPState),
1553     .class_init    = sysbus_esp_class_init,
1554 };
1555 
1556 static void esp_finalize(Object *obj)
1557 {
1558     ESPState *s = ESP(obj);
1559 
1560     fifo8_destroy(&s->fifo);
1561     fifo8_destroy(&s->cmdfifo);
1562 }
1563 
1564 static void esp_init(Object *obj)
1565 {
1566     ESPState *s = ESP(obj);
1567 
1568     fifo8_create(&s->fifo, ESP_FIFO_SZ);
1569     fifo8_create(&s->cmdfifo, ESP_CMDFIFO_SZ);
1570 }
1571 
1572 static void esp_class_init(ObjectClass *klass, void *data)
1573 {
1574     DeviceClass *dc = DEVICE_CLASS(klass);
1575 
1576     /* internal device for sysbusesp/pciespscsi, not user-creatable */
1577     dc->user_creatable = false;
1578     set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
1579 }
1580 
1581 static const TypeInfo esp_info = {
1582     .name = TYPE_ESP,
1583     .parent = TYPE_DEVICE,
1584     .instance_init = esp_init,
1585     .instance_finalize = esp_finalize,
1586     .instance_size = sizeof(ESPState),
1587     .class_init = esp_class_init,
1588 };
1589 
1590 static void esp_register_types(void)
1591 {
1592     type_register_static(&sysbus_esp_info);
1593     type_register_static(&esp_info);
1594 }
1595 
1596 type_init(esp_register_types)
1597