xref: /qemu/hw/scsi/esp.c (revision 3c7f3c8b5755d855be868ee05099fcee93d06bfe)
1 /*
2  * QEMU ESP/NCR53C9x emulation
3  *
4  * Copyright (c) 2005-2006 Fabrice Bellard
5  * Copyright (c) 2012 Herve Poussineau
6  *
7  * Permission is hereby granted, free of charge, to any person obtaining a copy
8  * of this software and associated documentation files (the "Software"), to deal
9  * in the Software without restriction, including without limitation the rights
10  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
11  * copies of the Software, and to permit persons to whom the Software is
12  * furnished to do so, subject to the following conditions:
13  *
14  * The above copyright notice and this permission notice shall be included in
15  * all copies or substantial portions of the Software.
16  *
17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
18  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
20  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
21  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
22  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
23  * THE SOFTWARE.
24  */
25 
26 #include "qemu/osdep.h"
27 #include "hw/sysbus.h"
28 #include "migration/vmstate.h"
29 #include "hw/irq.h"
30 #include "hw/scsi/esp.h"
31 #include "trace.h"
32 #include "qemu/log.h"
33 #include "qemu/module.h"
34 
35 /*
36  * On Sparc32, this is the ESP (NCR53C90) part of chip STP2000 (Master I/O),
37  * also produced as NCR89C100. See
38  * http://www.ibiblio.org/pub/historic-linux/early-ports/Sparc/NCR/NCR89C100.txt
39  * and
40  * http://www.ibiblio.org/pub/historic-linux/early-ports/Sparc/NCR/NCR53C9X.txt
41  *
42  * On Macintosh Quadra it is a NCR53C96.
43  */
44 
45 static void esp_raise_irq(ESPState *s)
46 {
47     if (!(s->rregs[ESP_RSTAT] & STAT_INT)) {
48         s->rregs[ESP_RSTAT] |= STAT_INT;
49         qemu_irq_raise(s->irq);
50         trace_esp_raise_irq();
51     }
52 }
53 
54 static void esp_lower_irq(ESPState *s)
55 {
56     if (s->rregs[ESP_RSTAT] & STAT_INT) {
57         s->rregs[ESP_RSTAT] &= ~STAT_INT;
58         qemu_irq_lower(s->irq);
59         trace_esp_lower_irq();
60     }
61 }
62 
63 static void esp_raise_drq(ESPState *s)
64 {
65     qemu_irq_raise(s->irq_data);
66     trace_esp_raise_drq();
67 }
68 
69 static void esp_lower_drq(ESPState *s)
70 {
71     qemu_irq_lower(s->irq_data);
72     trace_esp_lower_drq();
73 }
74 
75 void esp_dma_enable(ESPState *s, int irq, int level)
76 {
77     if (level) {
78         s->dma_enabled = 1;
79         trace_esp_dma_enable();
80         if (s->dma_cb) {
81             s->dma_cb(s);
82             s->dma_cb = NULL;
83         }
84     } else {
85         trace_esp_dma_disable();
86         s->dma_enabled = 0;
87     }
88 }
89 
90 void esp_request_cancelled(SCSIRequest *req)
91 {
92     ESPState *s = req->hba_private;
93 
94     if (req == s->current_req) {
95         scsi_req_unref(s->current_req);
96         s->current_req = NULL;
97         s->current_dev = NULL;
98         s->async_len = 0;
99     }
100 }
101 
102 static void esp_fifo_push(Fifo8 *fifo, uint8_t val)
103 {
104     if (fifo8_num_used(fifo) == fifo->capacity) {
105         trace_esp_error_fifo_overrun();
106         return;
107     }
108 
109     fifo8_push(fifo, val);
110 }
111 
112 static uint8_t esp_fifo_pop(Fifo8 *fifo)
113 {
114     if (fifo8_is_empty(fifo)) {
115         return 0;
116     }
117 
118     return fifo8_pop(fifo);
119 }
120 
121 static uint32_t esp_fifo_pop_buf(Fifo8 *fifo, uint8_t *dest, int maxlen)
122 {
123     const uint8_t *buf;
124     uint32_t n, n2;
125     int len;
126 
127     if (maxlen == 0) {
128         return 0;
129     }
130 
131     len = maxlen;
132     buf = fifo8_pop_buf(fifo, len, &n);
133     if (dest) {
134         memcpy(dest, buf, n);
135     }
136 
137     /* Add FIFO wraparound if needed */
138     len -= n;
139     len = MIN(len, fifo8_num_used(fifo));
140     if (len) {
141         buf = fifo8_pop_buf(fifo, len, &n2);
142         if (dest) {
143             memcpy(&dest[n], buf, n2);
144         }
145         n += n2;
146     }
147 
148     return n;
149 }
150 
151 static uint32_t esp_get_tc(ESPState *s)
152 {
153     uint32_t dmalen;
154 
155     dmalen = s->rregs[ESP_TCLO];
156     dmalen |= s->rregs[ESP_TCMID] << 8;
157     dmalen |= s->rregs[ESP_TCHI] << 16;
158 
159     return dmalen;
160 }
161 
162 static void esp_set_tc(ESPState *s, uint32_t dmalen)
163 {
164     uint32_t old_tc = esp_get_tc(s);
165 
166     s->rregs[ESP_TCLO] = dmalen;
167     s->rregs[ESP_TCMID] = dmalen >> 8;
168     s->rregs[ESP_TCHI] = dmalen >> 16;
169 
170     if (old_tc && dmalen == 0) {
171         s->rregs[ESP_RSTAT] |= STAT_TC;
172     }
173 }
174 
175 static uint32_t esp_get_stc(ESPState *s)
176 {
177     uint32_t dmalen;
178 
179     dmalen = s->wregs[ESP_TCLO];
180     dmalen |= s->wregs[ESP_TCMID] << 8;
181     dmalen |= s->wregs[ESP_TCHI] << 16;
182 
183     return dmalen;
184 }
185 
186 static const char *esp_phase_names[8] = {
187     "DATA OUT", "DATA IN", "COMMAND", "STATUS",
188     "(reserved)", "(reserved)", "MESSAGE OUT", "MESSAGE IN"
189 };
190 
191 static void esp_set_phase(ESPState *s, uint8_t phase)
192 {
193     s->rregs[ESP_RSTAT] &= ~7;
194     s->rregs[ESP_RSTAT] |= phase;
195 
196     trace_esp_set_phase(esp_phase_names[phase]);
197 }
198 
199 static uint8_t esp_pdma_read(ESPState *s)
200 {
201     uint8_t val;
202 
203     val = esp_fifo_pop(&s->fifo);
204     return val;
205 }
206 
207 static void esp_pdma_write(ESPState *s, uint8_t val)
208 {
209     uint32_t dmalen = esp_get_tc(s);
210 
211     if (dmalen == 0) {
212         return;
213     }
214 
215     esp_fifo_push(&s->fifo, val);
216 
217     dmalen--;
218     esp_set_tc(s, dmalen);
219 }
220 
221 static void esp_set_pdma_cb(ESPState *s, enum pdma_cb cb)
222 {
223     s->pdma_cb = cb;
224 }
225 
226 static int esp_select(ESPState *s)
227 {
228     int target;
229 
230     target = s->wregs[ESP_WBUSID] & BUSID_DID;
231 
232     s->ti_size = 0;
233 
234     if (s->current_req) {
235         /* Started a new command before the old one finished. Cancel it. */
236         scsi_req_cancel(s->current_req);
237     }
238 
239     s->current_dev = scsi_device_find(&s->bus, 0, target, 0);
240     if (!s->current_dev) {
241         /* No such drive */
242         s->rregs[ESP_RSTAT] = 0;
243         s->rregs[ESP_RINTR] = INTR_DC;
244         s->rregs[ESP_RSEQ] = SEQ_0;
245         esp_raise_irq(s);
246         return -1;
247     }
248 
249     /*
250      * Note that we deliberately don't raise the IRQ here: this will be done
251      * either in do_command_phase() for DATA OUT transfers or by the deferred
252      * IRQ mechanism in esp_transfer_data() for DATA IN transfers
253      */
254     s->rregs[ESP_RINTR] |= INTR_FC;
255     s->rregs[ESP_RSEQ] = SEQ_CD;
256     return 0;
257 }
258 
259 static uint32_t get_cmd(ESPState *s, uint32_t maxlen)
260 {
261     uint8_t buf[ESP_CMDFIFO_SZ];
262     uint32_t dmalen, n;
263     int target;
264 
265     target = s->wregs[ESP_WBUSID] & BUSID_DID;
266     if (s->dma) {
267         dmalen = MIN(esp_get_tc(s), maxlen);
268         if (dmalen == 0) {
269             return 0;
270         }
271         if (s->dma_memory_read) {
272             s->dma_memory_read(s->dma_opaque, buf, dmalen);
273             dmalen = MIN(fifo8_num_free(&s->cmdfifo), dmalen);
274             fifo8_push_all(&s->cmdfifo, buf, dmalen);
275             esp_set_tc(s, esp_get_tc(s) - dmalen);
276         } else {
277             return 0;
278         }
279     } else {
280         dmalen = MIN(fifo8_num_used(&s->fifo), maxlen);
281         if (dmalen == 0) {
282             return 0;
283         }
284         n = esp_fifo_pop_buf(&s->fifo, buf, dmalen);
285         n = MIN(fifo8_num_free(&s->cmdfifo), n);
286         fifo8_push_all(&s->cmdfifo, buf, n);
287     }
288     trace_esp_get_cmd(dmalen, target);
289 
290     return dmalen;
291 }
292 
293 static void do_command_phase(ESPState *s)
294 {
295     uint32_t cmdlen;
296     int32_t datalen;
297     SCSIDevice *current_lun;
298     uint8_t buf[ESP_CMDFIFO_SZ];
299 
300     trace_esp_do_command_phase(s->lun);
301     cmdlen = fifo8_num_used(&s->cmdfifo);
302     if (!cmdlen || !s->current_dev) {
303         return;
304     }
305     esp_fifo_pop_buf(&s->cmdfifo, buf, cmdlen);
306 
307     current_lun = scsi_device_find(&s->bus, 0, s->current_dev->id, s->lun);
308     if (!current_lun) {
309         /* No such drive */
310         s->rregs[ESP_RSTAT] = 0;
311         s->rregs[ESP_RINTR] = INTR_DC;
312         s->rregs[ESP_RSEQ] = SEQ_0;
313         esp_raise_irq(s);
314         return;
315     }
316 
317     s->current_req = scsi_req_new(current_lun, 0, s->lun, buf, cmdlen, s);
318     datalen = scsi_req_enqueue(s->current_req);
319     s->ti_size = datalen;
320     fifo8_reset(&s->cmdfifo);
321     if (datalen != 0) {
322         s->ti_cmd = 0;
323         if (datalen > 0) {
324             /*
325              * Switch to DATA IN phase but wait until initial data xfer is
326              * complete before raising the command completion interrupt
327              */
328             s->data_in_ready = false;
329             esp_set_phase(s, STAT_DI);
330         } else {
331             esp_set_phase(s, STAT_DO);
332             s->rregs[ESP_RINTR] |= INTR_BS | INTR_FC;
333             esp_raise_irq(s);
334             esp_lower_drq(s);
335         }
336         scsi_req_continue(s->current_req);
337         return;
338     }
339 }
340 
341 static void do_message_phase(ESPState *s)
342 {
343     if (s->cmdfifo_cdb_offset) {
344         uint8_t message = esp_fifo_pop(&s->cmdfifo);
345 
346         trace_esp_do_identify(message);
347         s->lun = message & 7;
348         s->cmdfifo_cdb_offset--;
349     }
350 
351     /* Ignore extended messages for now */
352     if (s->cmdfifo_cdb_offset) {
353         int len = MIN(s->cmdfifo_cdb_offset, fifo8_num_used(&s->cmdfifo));
354         esp_fifo_pop_buf(&s->cmdfifo, NULL, len);
355         s->cmdfifo_cdb_offset = 0;
356     }
357 }
358 
359 static void do_cmd(ESPState *s)
360 {
361     do_message_phase(s);
362     assert(s->cmdfifo_cdb_offset == 0);
363     do_command_phase(s);
364 }
365 
366 static void satn_pdma_cb(ESPState *s)
367 {
368     uint8_t buf[ESP_FIFO_SZ];
369     int n;
370 
371     /* Copy FIFO into cmdfifo */
372     n = esp_fifo_pop_buf(&s->fifo, buf, fifo8_num_used(&s->fifo));
373     n = MIN(fifo8_num_free(&s->cmdfifo), n);
374     fifo8_push_all(&s->cmdfifo, buf, n);
375 
376     if (!esp_get_tc(s) && !fifo8_is_empty(&s->cmdfifo)) {
377         s->cmdfifo_cdb_offset = 1;
378         s->do_cmd = 0;
379         do_cmd(s);
380     }
381 }
382 
383 static void handle_satn(ESPState *s)
384 {
385     int32_t cmdlen;
386 
387     if (s->dma && !s->dma_enabled) {
388         s->dma_cb = handle_satn;
389         return;
390     }
391     esp_set_pdma_cb(s, SATN_PDMA_CB);
392     if (esp_select(s) < 0) {
393         return;
394     }
395     cmdlen = get_cmd(s, ESP_CMDFIFO_SZ);
396     if (cmdlen > 0) {
397         s->cmdfifo_cdb_offset = 1;
398         s->do_cmd = 0;
399         do_cmd(s);
400     } else if (cmdlen == 0) {
401         if (s->dma) {
402             esp_raise_drq(s);
403         }
404         s->do_cmd = 1;
405         /* Target present, but no cmd yet - switch to command phase */
406         s->rregs[ESP_RSEQ] = SEQ_CD;
407         esp_set_phase(s, STAT_CD);
408     }
409 }
410 
411 static void s_without_satn_pdma_cb(ESPState *s)
412 {
413     uint8_t buf[ESP_FIFO_SZ];
414     int n;
415 
416     /* Copy FIFO into cmdfifo */
417     n = esp_fifo_pop_buf(&s->fifo, buf, fifo8_num_used(&s->fifo));
418     n = MIN(fifo8_num_free(&s->cmdfifo), n);
419     fifo8_push_all(&s->cmdfifo, buf, n);
420 
421     if (!esp_get_tc(s) && !fifo8_is_empty(&s->cmdfifo)) {
422         s->cmdfifo_cdb_offset = 0;
423         s->do_cmd = 0;
424         do_cmd(s);
425     }
426 }
427 
428 static void handle_s_without_atn(ESPState *s)
429 {
430     int32_t cmdlen;
431 
432     if (s->dma && !s->dma_enabled) {
433         s->dma_cb = handle_s_without_atn;
434         return;
435     }
436     esp_set_pdma_cb(s, S_WITHOUT_SATN_PDMA_CB);
437     if (esp_select(s) < 0) {
438         return;
439     }
440     cmdlen = get_cmd(s, ESP_CMDFIFO_SZ);
441     if (cmdlen > 0) {
442         s->cmdfifo_cdb_offset = 0;
443         s->do_cmd = 0;
444         do_cmd(s);
445     } else if (cmdlen == 0) {
446         if (s->dma) {
447             esp_raise_drq(s);
448         }
449         s->do_cmd = 1;
450         /* Target present, but no cmd yet - switch to command phase */
451         s->rregs[ESP_RSEQ] = SEQ_CD;
452         esp_set_phase(s, STAT_CD);
453     }
454 }
455 
456 static void satn_stop_pdma_cb(ESPState *s)
457 {
458     uint8_t buf[ESP_FIFO_SZ];
459     int n;
460 
461     /* Copy FIFO into cmdfifo */
462     n = esp_fifo_pop_buf(&s->fifo, buf, fifo8_num_used(&s->fifo));
463     n = MIN(fifo8_num_free(&s->cmdfifo), n);
464     fifo8_push_all(&s->cmdfifo, buf, n);
465 
466     if (!esp_get_tc(s) && !fifo8_is_empty(&s->cmdfifo)) {
467         trace_esp_handle_satn_stop(fifo8_num_used(&s->cmdfifo));
468         s->do_cmd = 1;
469         s->cmdfifo_cdb_offset = 1;
470         esp_set_phase(s, STAT_CD);
471         s->rregs[ESP_RSTAT] |= STAT_TC;
472         s->rregs[ESP_RINTR] |= INTR_BS | INTR_FC;
473         s->rregs[ESP_RSEQ] = SEQ_CD;
474         esp_raise_irq(s);
475     }
476 }
477 
478 static void handle_satn_stop(ESPState *s)
479 {
480     int32_t cmdlen;
481 
482     if (s->dma && !s->dma_enabled) {
483         s->dma_cb = handle_satn_stop;
484         return;
485     }
486     esp_set_pdma_cb(s, SATN_STOP_PDMA_CB);
487     if (esp_select(s) < 0) {
488         return;
489     }
490     cmdlen = get_cmd(s, 1);
491     if (cmdlen > 0) {
492         trace_esp_handle_satn_stop(fifo8_num_used(&s->cmdfifo));
493         s->do_cmd = 1;
494         s->cmdfifo_cdb_offset = 1;
495         esp_set_phase(s, STAT_MO);
496         s->rregs[ESP_RINTR] |= INTR_BS | INTR_FC;
497         s->rregs[ESP_RSEQ] = SEQ_MO;
498         esp_raise_irq(s);
499     } else if (cmdlen == 0) {
500         if (s->dma) {
501             esp_raise_drq(s);
502         }
503         s->do_cmd = 1;
504         /* Target present, switch to message out phase */
505         s->rregs[ESP_RSEQ] = SEQ_MO;
506         esp_set_phase(s, STAT_MO);
507     }
508 }
509 
510 static void write_response_pdma_cb(ESPState *s)
511 {
512     esp_set_phase(s, STAT_ST);
513     s->rregs[ESP_RINTR] |= INTR_BS | INTR_FC;
514     s->rregs[ESP_RSEQ] = SEQ_CD;
515     esp_raise_irq(s);
516 }
517 
518 static void write_response(ESPState *s)
519 {
520     uint8_t buf[2];
521 
522     trace_esp_write_response(s->status);
523 
524     buf[0] = s->status;
525     buf[1] = 0;
526 
527     if (s->dma) {
528         if (s->dma_memory_write) {
529             s->dma_memory_write(s->dma_opaque, buf, 2);
530             esp_set_phase(s, STAT_ST);
531             s->rregs[ESP_RINTR] |= INTR_BS | INTR_FC;
532             s->rregs[ESP_RSEQ] = SEQ_CD;
533         } else {
534             esp_set_pdma_cb(s, WRITE_RESPONSE_PDMA_CB);
535             esp_raise_drq(s);
536             return;
537         }
538     } else {
539         fifo8_reset(&s->fifo);
540         fifo8_push_all(&s->fifo, buf, 2);
541         s->rregs[ESP_RFLAGS] = 2;
542     }
543     esp_raise_irq(s);
544 }
545 
546 static void esp_dma_ti_check(ESPState *s)
547 {
548     if (esp_get_tc(s) == 0 && fifo8_num_used(&s->fifo) < 2) {
549         s->rregs[ESP_RINTR] |= INTR_BS;
550         esp_raise_irq(s);
551         esp_lower_drq(s);
552     }
553 }
554 
555 static void do_dma_pdma_cb(ESPState *s)
556 {
557     int to_device = ((s->rregs[ESP_RSTAT] & 7) == STAT_DO);
558     uint8_t buf[ESP_CMDFIFO_SZ];
559     int len;
560     uint32_t n;
561 
562     if (s->do_cmd) {
563         /* Copy FIFO into cmdfifo */
564         n = esp_fifo_pop_buf(&s->fifo, buf, fifo8_num_used(&s->fifo));
565         n = MIN(fifo8_num_free(&s->cmdfifo), n);
566         fifo8_push_all(&s->cmdfifo, buf, n);
567 
568         /* Ensure we have received complete command after SATN and stop */
569         if (esp_get_tc(s) || fifo8_is_empty(&s->cmdfifo)) {
570             return;
571         }
572 
573         s->ti_size = 0;
574         if ((s->rregs[ESP_RSTAT] & 7) == STAT_CD) {
575             /* No command received */
576             if (s->cmdfifo_cdb_offset == fifo8_num_used(&s->cmdfifo)) {
577                 return;
578             }
579 
580             /* Command has been received */
581             s->do_cmd = 0;
582             do_cmd(s);
583         } else {
584             /*
585              * Extra message out bytes received: update cmdfifo_cdb_offset
586              * and then switch to command phase
587              */
588             s->cmdfifo_cdb_offset = fifo8_num_used(&s->cmdfifo);
589             esp_set_phase(s, STAT_CD);
590             s->rregs[ESP_RSEQ] = SEQ_CD;
591             s->rregs[ESP_RINTR] |= INTR_BS;
592             esp_raise_irq(s);
593         }
594         return;
595     }
596 
597     if (!s->current_req) {
598         return;
599     }
600 
601     if (to_device) {
602         /* Copy FIFO data to device */
603         len = MIN(s->async_len, ESP_FIFO_SZ);
604         len = MIN(len, fifo8_num_used(&s->fifo));
605         n = esp_fifo_pop_buf(&s->fifo, s->async_buf, len);
606         s->async_buf += n;
607         s->async_len -= n;
608         s->ti_size += n;
609 
610         if (s->async_len == 0 && fifo8_num_used(&s->fifo) < 2) {
611             /* Defer until the scsi layer has completed */
612             scsi_req_continue(s->current_req);
613             return;
614         }
615 
616         esp_dma_ti_check(s);
617     } else {
618         if (s->async_len == 0 && fifo8_num_used(&s->fifo) < 2) {
619             /* Defer until the scsi layer has completed */
620             scsi_req_continue(s->current_req);
621             s->data_in_ready = false;
622             return;
623         }
624 
625         esp_dma_ti_check(s);
626 
627         /* Copy device data to FIFO */
628         len = MIN(s->async_len, esp_get_tc(s));
629         len = MIN(len, fifo8_num_free(&s->fifo));
630         fifo8_push_all(&s->fifo, s->async_buf, len);
631         s->async_buf += len;
632         s->async_len -= len;
633         s->ti_size -= len;
634         esp_set_tc(s, esp_get_tc(s) - len);
635     }
636 }
637 
638 static void esp_do_dma(ESPState *s)
639 {
640     uint32_t len, cmdlen;
641     int to_device = ((s->rregs[ESP_RSTAT] & 7) == STAT_DO);
642     uint8_t buf[ESP_CMDFIFO_SZ];
643     int n;
644 
645     len = esp_get_tc(s);
646     if (s->do_cmd) {
647         /*
648          * handle_ti_cmd() case: esp_do_dma() is called only from
649          * handle_ti_cmd() with do_cmd != NULL (see the assert())
650          */
651         cmdlen = fifo8_num_used(&s->cmdfifo);
652         trace_esp_do_dma(cmdlen, len);
653         if (s->dma_memory_read) {
654             len = MIN(len, fifo8_num_free(&s->cmdfifo));
655             s->dma_memory_read(s->dma_opaque, buf, len);
656             fifo8_push_all(&s->cmdfifo, buf, len);
657             esp_set_tc(s, esp_get_tc(s) - len);
658         } else {
659             n = esp_fifo_pop_buf(&s->fifo, buf, fifo8_num_used(&s->fifo));
660             n = MIN(fifo8_num_free(&s->cmdfifo), n);
661             fifo8_push_all(&s->cmdfifo, buf, n);
662             esp_set_tc(s, esp_get_tc(s) - n);
663 
664             esp_set_pdma_cb(s, DO_DMA_PDMA_CB);
665             esp_raise_drq(s);
666 
667             /* Ensure we have received complete command after SATN and stop */
668             if (esp_get_tc(s) || fifo8_is_empty(&s->cmdfifo)) {
669                 return;
670             }
671         }
672         trace_esp_handle_ti_cmd(cmdlen);
673         s->ti_size = 0;
674         if ((s->rregs[ESP_RSTAT] & 7) == STAT_CD) {
675             /* No command received */
676             if (s->cmdfifo_cdb_offset == fifo8_num_used(&s->cmdfifo)) {
677                 return;
678             }
679 
680             /* Command has been received */
681             s->do_cmd = 0;
682             do_cmd(s);
683         } else {
684             /*
685              * Extra message out bytes received: update cmdfifo_cdb_offset
686              * and then switch to command phase
687              */
688             s->cmdfifo_cdb_offset = fifo8_num_used(&s->cmdfifo);
689             esp_set_phase(s, STAT_CD);
690             s->rregs[ESP_RSEQ] = SEQ_CD;
691             s->rregs[ESP_RINTR] |= INTR_BS;
692             esp_raise_irq(s);
693         }
694         return;
695     }
696     if (!s->current_req) {
697         return;
698     }
699     if (s->async_len == 0) {
700         /* Defer until data is available.  */
701         return;
702     }
703     if (len > s->async_len) {
704         len = s->async_len;
705     }
706     if (to_device) {
707         if (s->dma_memory_read) {
708             s->dma_memory_read(s->dma_opaque, s->async_buf, len);
709 
710             esp_set_tc(s, esp_get_tc(s) - len);
711             s->async_buf += len;
712             s->async_len -= len;
713             s->ti_size += len;
714 
715             if (s->async_len == 0 && fifo8_num_used(&s->fifo) < 2) {
716                 /* Defer until the scsi layer has completed */
717                 scsi_req_continue(s->current_req);
718                 return;
719             }
720 
721             esp_dma_ti_check(s);
722         } else {
723             /* Copy FIFO data to device */
724             len = MIN(s->async_len, ESP_FIFO_SZ);
725             len = MIN(len, fifo8_num_used(&s->fifo));
726             n = esp_fifo_pop_buf(&s->fifo, s->async_buf, len);
727             s->async_buf += n;
728             s->async_len -= n;
729             s->ti_size += n;
730 
731             esp_set_pdma_cb(s, DO_DMA_PDMA_CB);
732             esp_raise_drq(s);
733 
734             if (s->async_len == 0 && fifo8_num_used(&s->fifo) < 2) {
735                 /* Defer until the scsi layer has completed */
736                 scsi_req_continue(s->current_req);
737                 return;
738             }
739 
740             esp_dma_ti_check(s);
741         }
742     } else {
743         if (s->dma_memory_write) {
744             s->dma_memory_write(s->dma_opaque, s->async_buf, len);
745 
746             esp_set_tc(s, esp_get_tc(s) - len);
747             s->async_buf += len;
748             s->async_len -= len;
749             s->ti_size -= len;
750 
751             if (s->async_len == 0 && fifo8_num_used(&s->fifo) < 2) {
752                 /* Defer until the scsi layer has completed */
753                 scsi_req_continue(s->current_req);
754                 return;
755             }
756 
757             esp_dma_ti_check(s);
758         } else {
759             /* Copy device data to FIFO */
760             len = MIN(len, fifo8_num_free(&s->fifo));
761             fifo8_push_all(&s->fifo, s->async_buf, len);
762             s->async_buf += len;
763             s->async_len -= len;
764             s->ti_size -= len;
765             esp_set_tc(s, esp_get_tc(s) - len);
766             esp_set_pdma_cb(s, DO_DMA_PDMA_CB);
767             esp_raise_drq(s);
768 
769             if (s->async_len == 0 && fifo8_num_used(&s->fifo) < 2) {
770                 /* Defer until the scsi layer has completed */
771                 scsi_req_continue(s->current_req);
772                 return;
773             }
774 
775             esp_dma_ti_check(s);
776         }
777     }
778 }
779 
780 static void esp_do_nodma(ESPState *s)
781 {
782     int to_device = ((s->rregs[ESP_RSTAT] & 7) == STAT_DO);
783     uint8_t buf[ESP_FIFO_SZ];
784     uint32_t cmdlen;
785     int len, n;
786 
787     if (s->do_cmd) {
788         /* Copy FIFO into cmdfifo */
789         n = esp_fifo_pop_buf(&s->fifo, buf, fifo8_num_used(&s->fifo));
790         n = MIN(fifo8_num_free(&s->cmdfifo), n);
791         fifo8_push_all(&s->cmdfifo, buf, n);
792 
793         cmdlen = fifo8_num_used(&s->cmdfifo);
794         trace_esp_handle_ti_cmd(cmdlen);
795         s->ti_size = 0;
796         if ((s->rregs[ESP_RSTAT] & 7) == STAT_CD) {
797             /* No command received */
798             if (s->cmdfifo_cdb_offset == fifo8_num_used(&s->cmdfifo)) {
799                 return;
800             }
801 
802             /* Command has been received */
803             s->do_cmd = 0;
804             do_cmd(s);
805         } else {
806             /*
807              * Extra message out bytes received: update cmdfifo_cdb_offset
808              * and then switch to command phase
809              */
810             s->cmdfifo_cdb_offset = fifo8_num_used(&s->cmdfifo);
811             esp_set_phase(s, STAT_CD);
812             s->rregs[ESP_RSEQ] = SEQ_CD;
813             s->rregs[ESP_RINTR] |= INTR_BS;
814             esp_raise_irq(s);
815         }
816         return;
817     }
818 
819     if (!s->current_req) {
820         return;
821     }
822 
823     if (s->async_len == 0) {
824         /* Defer until data is available.  */
825         return;
826     }
827 
828     if (to_device) {
829         len = MIN(s->async_len, ESP_FIFO_SZ);
830         len = MIN(len, fifo8_num_used(&s->fifo));
831         esp_fifo_pop_buf(&s->fifo, s->async_buf, len);
832         s->async_buf += len;
833         s->async_len -= len;
834         s->ti_size += len;
835     } else {
836         if (fifo8_is_empty(&s->fifo)) {
837             fifo8_push(&s->fifo, s->async_buf[0]);
838             s->async_buf++;
839             s->async_len--;
840             s->ti_size--;
841         }
842     }
843 
844     if (s->async_len == 0) {
845         scsi_req_continue(s->current_req);
846         return;
847     }
848 
849     s->rregs[ESP_RINTR] |= INTR_BS;
850     esp_raise_irq(s);
851 }
852 
853 static void esp_pdma_cb(ESPState *s)
854 {
855     switch (s->pdma_cb) {
856     case SATN_PDMA_CB:
857         satn_pdma_cb(s);
858         break;
859     case S_WITHOUT_SATN_PDMA_CB:
860         s_without_satn_pdma_cb(s);
861         break;
862     case SATN_STOP_PDMA_CB:
863         satn_stop_pdma_cb(s);
864         break;
865     case WRITE_RESPONSE_PDMA_CB:
866         write_response_pdma_cb(s);
867         break;
868     case DO_DMA_PDMA_CB:
869         do_dma_pdma_cb(s);
870         break;
871     default:
872         g_assert_not_reached();
873     }
874 }
875 
876 void esp_command_complete(SCSIRequest *req, size_t resid)
877 {
878     ESPState *s = req->hba_private;
879     int to_device = ((s->rregs[ESP_RSTAT] & 7) == STAT_DO);
880 
881     trace_esp_command_complete();
882 
883     /*
884      * Non-DMA transfers from the target will leave the last byte in
885      * the FIFO so don't reset ti_size in this case
886      */
887     if (s->dma || to_device) {
888         if (s->ti_size != 0) {
889             trace_esp_command_complete_unexpected();
890         }
891     }
892 
893     s->async_len = 0;
894     if (req->status) {
895         trace_esp_command_complete_fail();
896     }
897     s->status = req->status;
898 
899     /*
900      * Switch to status phase. For non-DMA transfers from the target the last
901      * byte is still in the FIFO
902      */
903     esp_set_phase(s, STAT_ST);
904     if (s->ti_size == 0) {
905         /*
906          * Transfer complete: force TC to zero just in case a TI command was
907          * requested for more data than the command returns (Solaris 8 does
908          * this)
909          */
910         esp_set_tc(s, 0);
911         esp_dma_ti_check(s);
912     } else {
913         /*
914          * Transfer truncated: raise INTR_BS to indicate early change of
915          * phase
916          */
917         s->rregs[ESP_RINTR] |= INTR_BS;
918         esp_raise_irq(s);
919         s->ti_size = 0;
920     }
921 
922     if (s->current_req) {
923         scsi_req_unref(s->current_req);
924         s->current_req = NULL;
925         s->current_dev = NULL;
926     }
927 }
928 
929 void esp_transfer_data(SCSIRequest *req, uint32_t len)
930 {
931     ESPState *s = req->hba_private;
932     int to_device = ((s->rregs[ESP_RSTAT] & 7) == STAT_DO);
933     uint32_t dmalen = esp_get_tc(s);
934 
935     assert(!s->do_cmd);
936     trace_esp_transfer_data(dmalen, s->ti_size);
937     s->async_len = len;
938     s->async_buf = scsi_req_get_buf(req);
939 
940     if (!to_device && !s->data_in_ready) {
941         /*
942          * Initial incoming data xfer is complete so raise command
943          * completion interrupt
944          */
945         s->data_in_ready = true;
946         s->rregs[ESP_RINTR] |= INTR_BS;
947         esp_raise_irq(s);
948     }
949 
950     /*
951      * Always perform the initial transfer upon reception of the next TI
952      * command to ensure the DMA/non-DMA status of the command is correct.
953      * It is not possible to use s->dma directly in the section below as
954      * some OSs send non-DMA NOP commands after a DMA transfer. Hence if the
955      * async data transfer is delayed then s->dma is set incorrectly.
956      */
957 
958     if (s->ti_cmd == (CMD_TI | CMD_DMA)) {
959         /* When the SCSI layer returns more data, raise deferred INTR_BS */
960         esp_dma_ti_check(s);
961 
962         esp_do_dma(s);
963     } else if (s->ti_cmd == CMD_TI) {
964         esp_do_nodma(s);
965     }
966 }
967 
968 static void handle_ti(ESPState *s)
969 {
970     uint32_t dmalen;
971 
972     if (s->dma && !s->dma_enabled) {
973         s->dma_cb = handle_ti;
974         return;
975     }
976 
977     s->ti_cmd = s->rregs[ESP_CMD];
978     if (s->dma) {
979         dmalen = esp_get_tc(s);
980         trace_esp_handle_ti(dmalen);
981         esp_do_dma(s);
982     } else {
983         trace_esp_handle_ti(s->ti_size);
984         esp_do_nodma(s);
985     }
986 }
987 
988 void esp_hard_reset(ESPState *s)
989 {
990     memset(s->rregs, 0, ESP_REGS);
991     memset(s->wregs, 0, ESP_REGS);
992     s->tchi_written = 0;
993     s->ti_size = 0;
994     s->async_len = 0;
995     fifo8_reset(&s->fifo);
996     fifo8_reset(&s->cmdfifo);
997     s->dma = 0;
998     s->do_cmd = 0;
999     s->dma_cb = NULL;
1000 
1001     s->rregs[ESP_CFG1] = 7;
1002 }
1003 
1004 static void esp_soft_reset(ESPState *s)
1005 {
1006     qemu_irq_lower(s->irq);
1007     qemu_irq_lower(s->irq_data);
1008     esp_hard_reset(s);
1009 }
1010 
1011 static void esp_bus_reset(ESPState *s)
1012 {
1013     bus_cold_reset(BUS(&s->bus));
1014 }
1015 
1016 static void parent_esp_reset(ESPState *s, int irq, int level)
1017 {
1018     if (level) {
1019         esp_soft_reset(s);
1020     }
1021 }
1022 
1023 static void esp_run_cmd(ESPState *s)
1024 {
1025     uint8_t cmd = s->rregs[ESP_CMD];
1026 
1027     if (cmd & CMD_DMA) {
1028         s->dma = 1;
1029         /* Reload DMA counter.  */
1030         if (esp_get_stc(s) == 0) {
1031             esp_set_tc(s, 0x10000);
1032         } else {
1033             esp_set_tc(s, esp_get_stc(s));
1034         }
1035     } else {
1036         s->dma = 0;
1037     }
1038     switch (cmd & CMD_CMD) {
1039     case CMD_NOP:
1040         trace_esp_mem_writeb_cmd_nop(cmd);
1041         break;
1042     case CMD_FLUSH:
1043         trace_esp_mem_writeb_cmd_flush(cmd);
1044         fifo8_reset(&s->fifo);
1045         break;
1046     case CMD_RESET:
1047         trace_esp_mem_writeb_cmd_reset(cmd);
1048         esp_soft_reset(s);
1049         break;
1050     case CMD_BUSRESET:
1051         trace_esp_mem_writeb_cmd_bus_reset(cmd);
1052         esp_bus_reset(s);
1053         if (!(s->wregs[ESP_CFG1] & CFG1_RESREPT)) {
1054             s->rregs[ESP_RINTR] |= INTR_RST;
1055             esp_raise_irq(s);
1056         }
1057         break;
1058     case CMD_TI:
1059         trace_esp_mem_writeb_cmd_ti(cmd);
1060         handle_ti(s);
1061         break;
1062     case CMD_ICCS:
1063         trace_esp_mem_writeb_cmd_iccs(cmd);
1064         write_response(s);
1065         s->rregs[ESP_RINTR] |= INTR_FC;
1066         esp_set_phase(s, STAT_MI);
1067         break;
1068     case CMD_MSGACC:
1069         trace_esp_mem_writeb_cmd_msgacc(cmd);
1070         s->rregs[ESP_RINTR] |= INTR_DC;
1071         s->rregs[ESP_RSEQ] = 0;
1072         s->rregs[ESP_RFLAGS] = 0;
1073         esp_raise_irq(s);
1074         break;
1075     case CMD_PAD:
1076         trace_esp_mem_writeb_cmd_pad(cmd);
1077         s->rregs[ESP_RSTAT] = STAT_TC;
1078         s->rregs[ESP_RINTR] |= INTR_FC;
1079         s->rregs[ESP_RSEQ] = 0;
1080         break;
1081     case CMD_SATN:
1082         trace_esp_mem_writeb_cmd_satn(cmd);
1083         break;
1084     case CMD_RSTATN:
1085         trace_esp_mem_writeb_cmd_rstatn(cmd);
1086         break;
1087     case CMD_SEL:
1088         trace_esp_mem_writeb_cmd_sel(cmd);
1089         handle_s_without_atn(s);
1090         break;
1091     case CMD_SELATN:
1092         trace_esp_mem_writeb_cmd_selatn(cmd);
1093         handle_satn(s);
1094         break;
1095     case CMD_SELATNS:
1096         trace_esp_mem_writeb_cmd_selatns(cmd);
1097         handle_satn_stop(s);
1098         break;
1099     case CMD_ENSEL:
1100         trace_esp_mem_writeb_cmd_ensel(cmd);
1101         s->rregs[ESP_RINTR] = 0;
1102         break;
1103     case CMD_DISSEL:
1104         trace_esp_mem_writeb_cmd_dissel(cmd);
1105         s->rregs[ESP_RINTR] = 0;
1106         esp_raise_irq(s);
1107         break;
1108     default:
1109         trace_esp_error_unhandled_command(cmd);
1110         break;
1111     }
1112 }
1113 
1114 uint64_t esp_reg_read(ESPState *s, uint32_t saddr)
1115 {
1116     uint32_t val;
1117 
1118     switch (saddr) {
1119     case ESP_FIFO:
1120         if (s->dma_memory_read && s->dma_memory_write &&
1121                 (s->rregs[ESP_RSTAT] & STAT_PIO_MASK) == 0) {
1122             /* Data out.  */
1123             qemu_log_mask(LOG_UNIMP, "esp: PIO data read not implemented\n");
1124             s->rregs[ESP_FIFO] = 0;
1125         } else {
1126             if ((s->rregs[ESP_RSTAT] & 0x7) == STAT_DI) {
1127                 if (s->ti_size) {
1128                     esp_do_nodma(s);
1129                 } else {
1130                     /*
1131                      * The last byte of a non-DMA transfer has been read out
1132                      * of the FIFO so switch to status phase
1133                      */
1134                     esp_set_phase(s, STAT_ST);
1135                 }
1136             }
1137             s->rregs[ESP_FIFO] = esp_fifo_pop(&s->fifo);
1138         }
1139         val = s->rregs[ESP_FIFO];
1140         break;
1141     case ESP_RINTR:
1142         /*
1143          * Clear sequence step, interrupt register and all status bits
1144          * except TC
1145          */
1146         val = s->rregs[ESP_RINTR];
1147         s->rregs[ESP_RINTR] = 0;
1148         s->rregs[ESP_RSTAT] &= ~STAT_TC;
1149         /*
1150          * According to the datasheet ESP_RSEQ should be cleared, but as the
1151          * emulation currently defers information transfers to the next TI
1152          * command leave it for now so that pedantic guests such as the old
1153          * Linux 2.6 driver see the correct flags before the next SCSI phase
1154          * transition.
1155          *
1156          * s->rregs[ESP_RSEQ] = SEQ_0;
1157          */
1158         esp_lower_irq(s);
1159         break;
1160     case ESP_TCHI:
1161         /* Return the unique id if the value has never been written */
1162         if (!s->tchi_written) {
1163             val = s->chip_id;
1164         } else {
1165             val = s->rregs[saddr];
1166         }
1167         break;
1168      case ESP_RFLAGS:
1169         /* Bottom 5 bits indicate number of bytes in FIFO */
1170         val = fifo8_num_used(&s->fifo);
1171         break;
1172     default:
1173         val = s->rregs[saddr];
1174         break;
1175     }
1176 
1177     trace_esp_mem_readb(saddr, val);
1178     return val;
1179 }
1180 
1181 void esp_reg_write(ESPState *s, uint32_t saddr, uint64_t val)
1182 {
1183     trace_esp_mem_writeb(saddr, s->wregs[saddr], val);
1184     switch (saddr) {
1185     case ESP_TCHI:
1186         s->tchi_written = true;
1187         /* fall through */
1188     case ESP_TCLO:
1189     case ESP_TCMID:
1190         s->rregs[ESP_RSTAT] &= ~STAT_TC;
1191         break;
1192     case ESP_FIFO:
1193         if (s->do_cmd) {
1194             if (!fifo8_is_full(&s->fifo)) {
1195                 esp_fifo_push(&s->fifo, val);
1196                 esp_fifo_push(&s->cmdfifo, fifo8_pop(&s->fifo));
1197             }
1198 
1199             /*
1200              * If any unexpected message out/command phase data is
1201              * transferred using non-DMA, raise the interrupt
1202              */
1203             if (s->rregs[ESP_CMD] == CMD_TI) {
1204                 s->rregs[ESP_RINTR] |= INTR_BS;
1205                 esp_raise_irq(s);
1206             }
1207         } else {
1208             esp_fifo_push(&s->fifo, val);
1209         }
1210         break;
1211     case ESP_CMD:
1212         s->rregs[saddr] = val;
1213         esp_run_cmd(s);
1214         break;
1215     case ESP_WBUSID ... ESP_WSYNO:
1216         break;
1217     case ESP_CFG1:
1218     case ESP_CFG2: case ESP_CFG3:
1219     case ESP_RES3: case ESP_RES4:
1220         s->rregs[saddr] = val;
1221         break;
1222     case ESP_WCCF ... ESP_WTEST:
1223         break;
1224     default:
1225         trace_esp_error_invalid_write(val, saddr);
1226         return;
1227     }
1228     s->wregs[saddr] = val;
1229 }
1230 
1231 static bool esp_mem_accepts(void *opaque, hwaddr addr,
1232                             unsigned size, bool is_write,
1233                             MemTxAttrs attrs)
1234 {
1235     return (size == 1) || (is_write && size == 4);
1236 }
1237 
1238 static bool esp_is_before_version_5(void *opaque, int version_id)
1239 {
1240     ESPState *s = ESP(opaque);
1241 
1242     version_id = MIN(version_id, s->mig_version_id);
1243     return version_id < 5;
1244 }
1245 
1246 static bool esp_is_version_5(void *opaque, int version_id)
1247 {
1248     ESPState *s = ESP(opaque);
1249 
1250     version_id = MIN(version_id, s->mig_version_id);
1251     return version_id >= 5;
1252 }
1253 
1254 static bool esp_is_version_6(void *opaque, int version_id)
1255 {
1256     ESPState *s = ESP(opaque);
1257 
1258     version_id = MIN(version_id, s->mig_version_id);
1259     return version_id >= 6;
1260 }
1261 
1262 int esp_pre_save(void *opaque)
1263 {
1264     ESPState *s = ESP(object_resolve_path_component(
1265                       OBJECT(opaque), "esp"));
1266 
1267     s->mig_version_id = vmstate_esp.version_id;
1268     return 0;
1269 }
1270 
1271 static int esp_post_load(void *opaque, int version_id)
1272 {
1273     ESPState *s = ESP(opaque);
1274     int len, i;
1275 
1276     version_id = MIN(version_id, s->mig_version_id);
1277 
1278     if (version_id < 5) {
1279         esp_set_tc(s, s->mig_dma_left);
1280 
1281         /* Migrate ti_buf to fifo */
1282         len = s->mig_ti_wptr - s->mig_ti_rptr;
1283         for (i = 0; i < len; i++) {
1284             fifo8_push(&s->fifo, s->mig_ti_buf[i]);
1285         }
1286 
1287         /* Migrate cmdbuf to cmdfifo */
1288         for (i = 0; i < s->mig_cmdlen; i++) {
1289             fifo8_push(&s->cmdfifo, s->mig_cmdbuf[i]);
1290         }
1291     }
1292 
1293     s->mig_version_id = vmstate_esp.version_id;
1294     return 0;
1295 }
1296 
1297 /*
1298  * PDMA (or pseudo-DMA) is only used on the Macintosh and requires the
1299  * guest CPU to perform the transfers between the SCSI bus and memory
1300  * itself. This is indicated by the dma_memory_read and dma_memory_write
1301  * functions being NULL (in contrast to the ESP PCI device) whilst
1302  * dma_enabled is still set.
1303  */
1304 
1305 static bool esp_pdma_needed(void *opaque)
1306 {
1307     ESPState *s = ESP(opaque);
1308 
1309     return s->dma_memory_read == NULL && s->dma_memory_write == NULL &&
1310            s->dma_enabled;
1311 }
1312 
1313 static const VMStateDescription vmstate_esp_pdma = {
1314     .name = "esp/pdma",
1315     .version_id = 0,
1316     .minimum_version_id = 0,
1317     .needed = esp_pdma_needed,
1318     .fields = (const VMStateField[]) {
1319         VMSTATE_UINT8(pdma_cb, ESPState),
1320         VMSTATE_END_OF_LIST()
1321     }
1322 };
1323 
1324 const VMStateDescription vmstate_esp = {
1325     .name = "esp",
1326     .version_id = 6,
1327     .minimum_version_id = 3,
1328     .post_load = esp_post_load,
1329     .fields = (const VMStateField[]) {
1330         VMSTATE_BUFFER(rregs, ESPState),
1331         VMSTATE_BUFFER(wregs, ESPState),
1332         VMSTATE_INT32(ti_size, ESPState),
1333         VMSTATE_UINT32_TEST(mig_ti_rptr, ESPState, esp_is_before_version_5),
1334         VMSTATE_UINT32_TEST(mig_ti_wptr, ESPState, esp_is_before_version_5),
1335         VMSTATE_BUFFER_TEST(mig_ti_buf, ESPState, esp_is_before_version_5),
1336         VMSTATE_UINT32(status, ESPState),
1337         VMSTATE_UINT32_TEST(mig_deferred_status, ESPState,
1338                             esp_is_before_version_5),
1339         VMSTATE_BOOL_TEST(mig_deferred_complete, ESPState,
1340                           esp_is_before_version_5),
1341         VMSTATE_UINT32(dma, ESPState),
1342         VMSTATE_STATIC_BUFFER(mig_cmdbuf, ESPState, 0,
1343                               esp_is_before_version_5, 0, 16),
1344         VMSTATE_STATIC_BUFFER(mig_cmdbuf, ESPState, 4,
1345                               esp_is_before_version_5, 16,
1346                               sizeof(typeof_field(ESPState, mig_cmdbuf))),
1347         VMSTATE_UINT32_TEST(mig_cmdlen, ESPState, esp_is_before_version_5),
1348         VMSTATE_UINT32(do_cmd, ESPState),
1349         VMSTATE_UINT32_TEST(mig_dma_left, ESPState, esp_is_before_version_5),
1350         VMSTATE_BOOL_TEST(data_in_ready, ESPState, esp_is_version_5),
1351         VMSTATE_UINT8_TEST(cmdfifo_cdb_offset, ESPState, esp_is_version_5),
1352         VMSTATE_FIFO8_TEST(fifo, ESPState, esp_is_version_5),
1353         VMSTATE_FIFO8_TEST(cmdfifo, ESPState, esp_is_version_5),
1354         VMSTATE_UINT8_TEST(ti_cmd, ESPState, esp_is_version_5),
1355         VMSTATE_UINT8_TEST(lun, ESPState, esp_is_version_6),
1356         VMSTATE_END_OF_LIST()
1357     },
1358     .subsections = (const VMStateDescription * const []) {
1359         &vmstate_esp_pdma,
1360         NULL
1361     }
1362 };
1363 
1364 static void sysbus_esp_mem_write(void *opaque, hwaddr addr,
1365                                  uint64_t val, unsigned int size)
1366 {
1367     SysBusESPState *sysbus = opaque;
1368     ESPState *s = ESP(&sysbus->esp);
1369     uint32_t saddr;
1370 
1371     saddr = addr >> sysbus->it_shift;
1372     esp_reg_write(s, saddr, val);
1373 }
1374 
1375 static uint64_t sysbus_esp_mem_read(void *opaque, hwaddr addr,
1376                                     unsigned int size)
1377 {
1378     SysBusESPState *sysbus = opaque;
1379     ESPState *s = ESP(&sysbus->esp);
1380     uint32_t saddr;
1381 
1382     saddr = addr >> sysbus->it_shift;
1383     return esp_reg_read(s, saddr);
1384 }
1385 
1386 static const MemoryRegionOps sysbus_esp_mem_ops = {
1387     .read = sysbus_esp_mem_read,
1388     .write = sysbus_esp_mem_write,
1389     .endianness = DEVICE_NATIVE_ENDIAN,
1390     .valid.accepts = esp_mem_accepts,
1391 };
1392 
1393 static void sysbus_esp_pdma_write(void *opaque, hwaddr addr,
1394                                   uint64_t val, unsigned int size)
1395 {
1396     SysBusESPState *sysbus = opaque;
1397     ESPState *s = ESP(&sysbus->esp);
1398 
1399     trace_esp_pdma_write(size);
1400 
1401     switch (size) {
1402     case 1:
1403         esp_pdma_write(s, val);
1404         break;
1405     case 2:
1406         esp_pdma_write(s, val >> 8);
1407         esp_pdma_write(s, val);
1408         break;
1409     }
1410     esp_pdma_cb(s);
1411 }
1412 
1413 static uint64_t sysbus_esp_pdma_read(void *opaque, hwaddr addr,
1414                                      unsigned int size)
1415 {
1416     SysBusESPState *sysbus = opaque;
1417     ESPState *s = ESP(&sysbus->esp);
1418     uint64_t val = 0;
1419 
1420     trace_esp_pdma_read(size);
1421 
1422     switch (size) {
1423     case 1:
1424         val = esp_pdma_read(s);
1425         break;
1426     case 2:
1427         val = esp_pdma_read(s);
1428         val = (val << 8) | esp_pdma_read(s);
1429         break;
1430     }
1431     esp_pdma_cb(s);
1432     return val;
1433 }
1434 
1435 static void *esp_load_request(QEMUFile *f, SCSIRequest *req)
1436 {
1437     ESPState *s = container_of(req->bus, ESPState, bus);
1438 
1439     scsi_req_ref(req);
1440     s->current_req = req;
1441     return s;
1442 }
1443 
1444 static const MemoryRegionOps sysbus_esp_pdma_ops = {
1445     .read = sysbus_esp_pdma_read,
1446     .write = sysbus_esp_pdma_write,
1447     .endianness = DEVICE_NATIVE_ENDIAN,
1448     .valid.min_access_size = 1,
1449     .valid.max_access_size = 4,
1450     .impl.min_access_size = 1,
1451     .impl.max_access_size = 2,
1452 };
1453 
1454 static const struct SCSIBusInfo esp_scsi_info = {
1455     .tcq = false,
1456     .max_target = ESP_MAX_DEVS,
1457     .max_lun = 7,
1458 
1459     .load_request = esp_load_request,
1460     .transfer_data = esp_transfer_data,
1461     .complete = esp_command_complete,
1462     .cancel = esp_request_cancelled
1463 };
1464 
1465 static void sysbus_esp_gpio_demux(void *opaque, int irq, int level)
1466 {
1467     SysBusESPState *sysbus = SYSBUS_ESP(opaque);
1468     ESPState *s = ESP(&sysbus->esp);
1469 
1470     switch (irq) {
1471     case 0:
1472         parent_esp_reset(s, irq, level);
1473         break;
1474     case 1:
1475         esp_dma_enable(s, irq, level);
1476         break;
1477     }
1478 }
1479 
1480 static void sysbus_esp_realize(DeviceState *dev, Error **errp)
1481 {
1482     SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
1483     SysBusESPState *sysbus = SYSBUS_ESP(dev);
1484     ESPState *s = ESP(&sysbus->esp);
1485 
1486     if (!qdev_realize(DEVICE(s), NULL, errp)) {
1487         return;
1488     }
1489 
1490     sysbus_init_irq(sbd, &s->irq);
1491     sysbus_init_irq(sbd, &s->irq_data);
1492     assert(sysbus->it_shift != -1);
1493 
1494     s->chip_id = TCHI_FAS100A;
1495     memory_region_init_io(&sysbus->iomem, OBJECT(sysbus), &sysbus_esp_mem_ops,
1496                           sysbus, "esp-regs", ESP_REGS << sysbus->it_shift);
1497     sysbus_init_mmio(sbd, &sysbus->iomem);
1498     memory_region_init_io(&sysbus->pdma, OBJECT(sysbus), &sysbus_esp_pdma_ops,
1499                           sysbus, "esp-pdma", 4);
1500     sysbus_init_mmio(sbd, &sysbus->pdma);
1501 
1502     qdev_init_gpio_in(dev, sysbus_esp_gpio_demux, 2);
1503 
1504     scsi_bus_init(&s->bus, sizeof(s->bus), dev, &esp_scsi_info);
1505 }
1506 
1507 static void sysbus_esp_hard_reset(DeviceState *dev)
1508 {
1509     SysBusESPState *sysbus = SYSBUS_ESP(dev);
1510     ESPState *s = ESP(&sysbus->esp);
1511 
1512     esp_hard_reset(s);
1513 }
1514 
1515 static void sysbus_esp_init(Object *obj)
1516 {
1517     SysBusESPState *sysbus = SYSBUS_ESP(obj);
1518 
1519     object_initialize_child(obj, "esp", &sysbus->esp, TYPE_ESP);
1520 }
1521 
1522 static const VMStateDescription vmstate_sysbus_esp_scsi = {
1523     .name = "sysbusespscsi",
1524     .version_id = 2,
1525     .minimum_version_id = 1,
1526     .pre_save = esp_pre_save,
1527     .fields = (const VMStateField[]) {
1528         VMSTATE_UINT8_V(esp.mig_version_id, SysBusESPState, 2),
1529         VMSTATE_STRUCT(esp, SysBusESPState, 0, vmstate_esp, ESPState),
1530         VMSTATE_END_OF_LIST()
1531     }
1532 };
1533 
1534 static void sysbus_esp_class_init(ObjectClass *klass, void *data)
1535 {
1536     DeviceClass *dc = DEVICE_CLASS(klass);
1537 
1538     dc->realize = sysbus_esp_realize;
1539     dc->reset = sysbus_esp_hard_reset;
1540     dc->vmsd = &vmstate_sysbus_esp_scsi;
1541     set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
1542 }
1543 
1544 static const TypeInfo sysbus_esp_info = {
1545     .name          = TYPE_SYSBUS_ESP,
1546     .parent        = TYPE_SYS_BUS_DEVICE,
1547     .instance_init = sysbus_esp_init,
1548     .instance_size = sizeof(SysBusESPState),
1549     .class_init    = sysbus_esp_class_init,
1550 };
1551 
1552 static void esp_finalize(Object *obj)
1553 {
1554     ESPState *s = ESP(obj);
1555 
1556     fifo8_destroy(&s->fifo);
1557     fifo8_destroy(&s->cmdfifo);
1558 }
1559 
1560 static void esp_init(Object *obj)
1561 {
1562     ESPState *s = ESP(obj);
1563 
1564     fifo8_create(&s->fifo, ESP_FIFO_SZ);
1565     fifo8_create(&s->cmdfifo, ESP_CMDFIFO_SZ);
1566 }
1567 
1568 static void esp_class_init(ObjectClass *klass, void *data)
1569 {
1570     DeviceClass *dc = DEVICE_CLASS(klass);
1571 
1572     /* internal device for sysbusesp/pciespscsi, not user-creatable */
1573     dc->user_creatable = false;
1574     set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
1575 }
1576 
1577 static const TypeInfo esp_info = {
1578     .name = TYPE_ESP,
1579     .parent = TYPE_DEVICE,
1580     .instance_init = esp_init,
1581     .instance_finalize = esp_finalize,
1582     .instance_size = sizeof(ESPState),
1583     .class_init = esp_class_init,
1584 };
1585 
1586 static void esp_register_types(void)
1587 {
1588     type_register_static(&sysbus_esp_info);
1589     type_register_static(&esp_info);
1590 }
1591 
1592 type_init(esp_register_types)
1593