xref: /qemu/hw/scsi/esp.c (revision 66fd5657338b7a1ca9c362a593e2daca5a9f4300)
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 handle_s_without_atn(ESPState *s)
412 {
413     int32_t cmdlen;
414 
415     if (s->dma && !s->dma_enabled) {
416         s->dma_cb = handle_s_without_atn;
417         return;
418     }
419     esp_set_pdma_cb(s, DO_DMA_PDMA_CB);
420     if (esp_select(s) < 0) {
421         return;
422     }
423     cmdlen = get_cmd(s, ESP_CMDFIFO_SZ);
424     if (cmdlen > 0) {
425         s->cmdfifo_cdb_offset = 0;
426         s->do_cmd = 0;
427         do_cmd(s);
428     } else if (cmdlen == 0) {
429         if (s->dma) {
430             esp_raise_drq(s);
431         }
432         s->do_cmd = 1;
433         /* Target present, but no cmd yet - switch to command phase */
434         s->rregs[ESP_RSEQ] = SEQ_CD;
435         esp_set_phase(s, STAT_CD);
436     }
437 }
438 
439 static void satn_stop_pdma_cb(ESPState *s)
440 {
441     uint8_t buf[ESP_FIFO_SZ];
442     int n;
443 
444     /* Copy FIFO into cmdfifo */
445     n = esp_fifo_pop_buf(&s->fifo, buf, fifo8_num_used(&s->fifo));
446     n = MIN(fifo8_num_free(&s->cmdfifo), n);
447     fifo8_push_all(&s->cmdfifo, buf, n);
448 
449     if (!esp_get_tc(s) && !fifo8_is_empty(&s->cmdfifo)) {
450         trace_esp_handle_satn_stop(fifo8_num_used(&s->cmdfifo));
451         s->do_cmd = 1;
452         s->cmdfifo_cdb_offset = 1;
453         esp_set_phase(s, STAT_CD);
454         s->rregs[ESP_RSTAT] |= STAT_TC;
455         s->rregs[ESP_RINTR] |= INTR_BS | INTR_FC;
456         s->rregs[ESP_RSEQ] = SEQ_CD;
457         esp_raise_irq(s);
458     }
459 }
460 
461 static void handle_satn_stop(ESPState *s)
462 {
463     int32_t cmdlen;
464 
465     if (s->dma && !s->dma_enabled) {
466         s->dma_cb = handle_satn_stop;
467         return;
468     }
469     esp_set_pdma_cb(s, SATN_STOP_PDMA_CB);
470     if (esp_select(s) < 0) {
471         return;
472     }
473     cmdlen = get_cmd(s, 1);
474     if (cmdlen > 0) {
475         trace_esp_handle_satn_stop(fifo8_num_used(&s->cmdfifo));
476         s->do_cmd = 1;
477         s->cmdfifo_cdb_offset = 1;
478         esp_set_phase(s, STAT_MO);
479         s->rregs[ESP_RINTR] |= INTR_BS | INTR_FC;
480         s->rregs[ESP_RSEQ] = SEQ_MO;
481         esp_raise_irq(s);
482     } else if (cmdlen == 0) {
483         if (s->dma) {
484             esp_raise_drq(s);
485         }
486         s->do_cmd = 1;
487         /* Target present, switch to message out phase */
488         s->rregs[ESP_RSEQ] = SEQ_MO;
489         esp_set_phase(s, STAT_MO);
490     }
491 }
492 
493 static void write_response_pdma_cb(ESPState *s)
494 {
495     esp_set_phase(s, STAT_ST);
496     s->rregs[ESP_RINTR] |= INTR_BS | INTR_FC;
497     s->rregs[ESP_RSEQ] = SEQ_CD;
498     esp_raise_irq(s);
499 }
500 
501 static void write_response(ESPState *s)
502 {
503     uint8_t buf[2];
504 
505     trace_esp_write_response(s->status);
506 
507     buf[0] = s->status;
508     buf[1] = 0;
509 
510     if (s->dma) {
511         if (s->dma_memory_write) {
512             s->dma_memory_write(s->dma_opaque, buf, 2);
513             esp_set_phase(s, STAT_ST);
514             s->rregs[ESP_RINTR] |= INTR_BS | INTR_FC;
515             s->rregs[ESP_RSEQ] = SEQ_CD;
516         } else {
517             esp_set_pdma_cb(s, WRITE_RESPONSE_PDMA_CB);
518             esp_raise_drq(s);
519             return;
520         }
521     } else {
522         fifo8_reset(&s->fifo);
523         fifo8_push_all(&s->fifo, buf, 2);
524         s->rregs[ESP_RFLAGS] = 2;
525     }
526     esp_raise_irq(s);
527 }
528 
529 static void esp_dma_ti_check(ESPState *s)
530 {
531     if (esp_get_tc(s) == 0 && fifo8_num_used(&s->fifo) < 2) {
532         s->rregs[ESP_RINTR] |= INTR_BS;
533         esp_raise_irq(s);
534         esp_lower_drq(s);
535     }
536 }
537 
538 static void do_dma_pdma_cb(ESPState *s)
539 {
540     int to_device = ((s->rregs[ESP_RSTAT] & 7) == STAT_DO);
541     uint8_t buf[ESP_CMDFIFO_SZ];
542     int len;
543     uint32_t n;
544 
545     if (s->do_cmd) {
546         /* Copy FIFO into cmdfifo */
547         n = esp_fifo_pop_buf(&s->fifo, buf, fifo8_num_used(&s->fifo));
548         n = MIN(fifo8_num_free(&s->cmdfifo), n);
549         fifo8_push_all(&s->cmdfifo, buf, n);
550 
551         /* Ensure we have received complete command after SATN and stop */
552         if (esp_get_tc(s) || fifo8_is_empty(&s->cmdfifo)) {
553             return;
554         }
555 
556         s->ti_size = 0;
557         if ((s->rregs[ESP_RSTAT] & 7) == STAT_CD) {
558             /* No command received */
559             if (s->cmdfifo_cdb_offset == fifo8_num_used(&s->cmdfifo)) {
560                 return;
561             }
562 
563             /* Command has been received */
564             s->do_cmd = 0;
565             do_cmd(s);
566         } else {
567             /*
568              * Extra message out bytes received: update cmdfifo_cdb_offset
569              * and then switch to command phase
570              */
571             s->cmdfifo_cdb_offset = fifo8_num_used(&s->cmdfifo);
572             esp_set_phase(s, STAT_CD);
573             s->rregs[ESP_RSEQ] = SEQ_CD;
574             s->rregs[ESP_RINTR] |= INTR_BS;
575             esp_raise_irq(s);
576         }
577         return;
578     }
579 
580     if (!s->current_req) {
581         return;
582     }
583 
584     if (to_device) {
585         /* Copy FIFO data to device */
586         len = MIN(s->async_len, ESP_FIFO_SZ);
587         len = MIN(len, fifo8_num_used(&s->fifo));
588         n = esp_fifo_pop_buf(&s->fifo, s->async_buf, len);
589         s->async_buf += n;
590         s->async_len -= n;
591         s->ti_size += n;
592 
593         if (s->async_len == 0 && fifo8_num_used(&s->fifo) < 2) {
594             /* Defer until the scsi layer has completed */
595             scsi_req_continue(s->current_req);
596             return;
597         }
598 
599         esp_dma_ti_check(s);
600     } else {
601         /* Copy device data to FIFO */
602         len = MIN(s->async_len, esp_get_tc(s));
603         len = MIN(len, fifo8_num_free(&s->fifo));
604         fifo8_push_all(&s->fifo, s->async_buf, len);
605         s->async_buf += len;
606         s->async_len -= len;
607         s->ti_size -= len;
608         esp_set_tc(s, esp_get_tc(s) - len);
609 
610         if (s->async_len == 0 && fifo8_num_used(&s->fifo) < 2) {
611             /* Defer until the scsi layer has completed */
612             scsi_req_continue(s->current_req);
613             s->data_in_ready = false;
614             return;
615         }
616 
617         esp_dma_ti_check(s);
618     }
619 }
620 
621 static void esp_do_dma(ESPState *s)
622 {
623     uint32_t len, cmdlen;
624     int to_device = ((s->rregs[ESP_RSTAT] & 7) == STAT_DO);
625     uint8_t buf[ESP_CMDFIFO_SZ];
626     int n;
627 
628     len = esp_get_tc(s);
629     if (s->do_cmd) {
630         /*
631          * handle_ti_cmd() case: esp_do_dma() is called only from
632          * handle_ti_cmd() with do_cmd != NULL (see the assert())
633          */
634         cmdlen = fifo8_num_used(&s->cmdfifo);
635         trace_esp_do_dma(cmdlen, len);
636         if (s->dma_memory_read) {
637             len = MIN(len, fifo8_num_free(&s->cmdfifo));
638             s->dma_memory_read(s->dma_opaque, buf, len);
639             fifo8_push_all(&s->cmdfifo, buf, len);
640             esp_set_tc(s, esp_get_tc(s) - len);
641         } else {
642             n = esp_fifo_pop_buf(&s->fifo, buf, fifo8_num_used(&s->fifo));
643             n = MIN(fifo8_num_free(&s->cmdfifo), n);
644             fifo8_push_all(&s->cmdfifo, buf, n);
645             esp_set_tc(s, esp_get_tc(s) - n);
646 
647             esp_set_pdma_cb(s, DO_DMA_PDMA_CB);
648             esp_raise_drq(s);
649 
650             /* Ensure we have received complete command after SATN and stop */
651             if (esp_get_tc(s) || fifo8_is_empty(&s->cmdfifo)) {
652                 return;
653             }
654         }
655         trace_esp_handle_ti_cmd(cmdlen);
656         s->ti_size = 0;
657         if ((s->rregs[ESP_RSTAT] & 7) == STAT_CD) {
658             /* No command received */
659             if (s->cmdfifo_cdb_offset == fifo8_num_used(&s->cmdfifo)) {
660                 return;
661             }
662 
663             /* Command has been received */
664             s->do_cmd = 0;
665             do_cmd(s);
666         } else {
667             /*
668              * Extra message out bytes received: update cmdfifo_cdb_offset
669              * and then switch to command phase
670              */
671             s->cmdfifo_cdb_offset = fifo8_num_used(&s->cmdfifo);
672             esp_set_phase(s, STAT_CD);
673             s->rregs[ESP_RSEQ] = SEQ_CD;
674             s->rregs[ESP_RINTR] |= INTR_BS;
675             esp_raise_irq(s);
676         }
677         return;
678     }
679     if (!s->current_req) {
680         return;
681     }
682     if (s->async_len == 0 && esp_get_tc(s) && s->ti_size) {
683         /* Defer until data is available.  */
684         return;
685     }
686     if (len > s->async_len) {
687         len = s->async_len;
688     }
689     if (to_device) {
690         if (s->dma_memory_read) {
691             s->dma_memory_read(s->dma_opaque, s->async_buf, len);
692 
693             esp_set_tc(s, esp_get_tc(s) - len);
694             s->async_buf += len;
695             s->async_len -= len;
696             s->ti_size += len;
697 
698             if (s->async_len == 0 && fifo8_num_used(&s->fifo) < 2) {
699                 /* Defer until the scsi layer has completed */
700                 scsi_req_continue(s->current_req);
701                 return;
702             }
703 
704             esp_dma_ti_check(s);
705         } else {
706             /* Copy FIFO data to device */
707             len = MIN(s->async_len, ESP_FIFO_SZ);
708             len = MIN(len, fifo8_num_used(&s->fifo));
709             n = esp_fifo_pop_buf(&s->fifo, s->async_buf, len);
710             s->async_buf += n;
711             s->async_len -= n;
712             s->ti_size += n;
713 
714             esp_set_pdma_cb(s, DO_DMA_PDMA_CB);
715             esp_raise_drq(s);
716 
717             if (s->async_len == 0 && fifo8_num_used(&s->fifo) < 2) {
718                 /* Defer until the scsi layer has completed */
719                 scsi_req_continue(s->current_req);
720                 return;
721             }
722 
723             esp_dma_ti_check(s);
724         }
725     } else {
726         if (s->dma_memory_write) {
727             s->dma_memory_write(s->dma_opaque, s->async_buf, len);
728 
729             esp_set_tc(s, esp_get_tc(s) - len);
730             s->async_buf += len;
731             s->async_len -= len;
732             s->ti_size -= len;
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         } else {
742             /* Copy device data to FIFO */
743             len = MIN(len, fifo8_num_free(&s->fifo));
744             fifo8_push_all(&s->fifo, s->async_buf, len);
745             s->async_buf += len;
746             s->async_len -= len;
747             s->ti_size -= len;
748             esp_set_tc(s, esp_get_tc(s) - len);
749             esp_set_pdma_cb(s, DO_DMA_PDMA_CB);
750             esp_raise_drq(s);
751 
752             if (s->async_len == 0 && fifo8_num_used(&s->fifo) < 2) {
753                 /* Defer until the scsi layer has completed */
754                 scsi_req_continue(s->current_req);
755                 return;
756             }
757 
758             esp_dma_ti_check(s);
759         }
760     }
761 }
762 
763 static void esp_do_nodma(ESPState *s)
764 {
765     int to_device = ((s->rregs[ESP_RSTAT] & 7) == STAT_DO);
766     uint8_t buf[ESP_FIFO_SZ];
767     uint32_t cmdlen;
768     int len, n;
769 
770     if (s->do_cmd) {
771         /* Copy FIFO into cmdfifo */
772         n = esp_fifo_pop_buf(&s->fifo, buf, fifo8_num_used(&s->fifo));
773         n = MIN(fifo8_num_free(&s->cmdfifo), n);
774         fifo8_push_all(&s->cmdfifo, buf, n);
775 
776         cmdlen = fifo8_num_used(&s->cmdfifo);
777         trace_esp_handle_ti_cmd(cmdlen);
778         s->ti_size = 0;
779         if ((s->rregs[ESP_RSTAT] & 7) == STAT_CD) {
780             /* No command received */
781             if (s->cmdfifo_cdb_offset == fifo8_num_used(&s->cmdfifo)) {
782                 return;
783             }
784 
785             /* Command has been received */
786             s->do_cmd = 0;
787             do_cmd(s);
788         } else {
789             /*
790              * Extra message out bytes received: update cmdfifo_cdb_offset
791              * and then switch to command phase
792              */
793             s->cmdfifo_cdb_offset = fifo8_num_used(&s->cmdfifo);
794             esp_set_phase(s, STAT_CD);
795             s->rregs[ESP_RSEQ] = SEQ_CD;
796             s->rregs[ESP_RINTR] |= INTR_BS;
797             esp_raise_irq(s);
798         }
799         return;
800     }
801 
802     if (!s->current_req) {
803         return;
804     }
805 
806     if (s->async_len == 0) {
807         /* Defer until data is available.  */
808         return;
809     }
810 
811     if (to_device) {
812         len = MIN(s->async_len, ESP_FIFO_SZ);
813         len = MIN(len, fifo8_num_used(&s->fifo));
814         esp_fifo_pop_buf(&s->fifo, s->async_buf, len);
815         s->async_buf += len;
816         s->async_len -= len;
817         s->ti_size += len;
818     } else {
819         if (fifo8_is_empty(&s->fifo)) {
820             fifo8_push(&s->fifo, s->async_buf[0]);
821             s->async_buf++;
822             s->async_len--;
823             s->ti_size--;
824         }
825     }
826 
827     if (s->async_len == 0) {
828         scsi_req_continue(s->current_req);
829         return;
830     }
831 
832     s->rregs[ESP_RINTR] |= INTR_BS;
833     esp_raise_irq(s);
834 }
835 
836 static void esp_pdma_cb(ESPState *s)
837 {
838     switch (s->pdma_cb) {
839     case SATN_PDMA_CB:
840         satn_pdma_cb(s);
841         break;
842     case SATN_STOP_PDMA_CB:
843         satn_stop_pdma_cb(s);
844         break;
845     case WRITE_RESPONSE_PDMA_CB:
846         write_response_pdma_cb(s);
847         break;
848     case DO_DMA_PDMA_CB:
849         do_dma_pdma_cb(s);
850         break;
851     default:
852         g_assert_not_reached();
853     }
854 }
855 
856 void esp_command_complete(SCSIRequest *req, size_t resid)
857 {
858     ESPState *s = req->hba_private;
859     int to_device = ((s->rregs[ESP_RSTAT] & 7) == STAT_DO);
860 
861     trace_esp_command_complete();
862 
863     /*
864      * Non-DMA transfers from the target will leave the last byte in
865      * the FIFO so don't reset ti_size in this case
866      */
867     if (s->dma || to_device) {
868         if (s->ti_size != 0) {
869             trace_esp_command_complete_unexpected();
870         }
871     }
872 
873     s->async_len = 0;
874     if (req->status) {
875         trace_esp_command_complete_fail();
876     }
877     s->status = req->status;
878 
879     /*
880      * Switch to status phase. For non-DMA transfers from the target the last
881      * byte is still in the FIFO
882      */
883     esp_set_phase(s, STAT_ST);
884     if (s->ti_size == 0) {
885         /*
886          * Transfer complete: force TC to zero just in case a TI command was
887          * requested for more data than the command returns (Solaris 8 does
888          * this)
889          */
890         esp_set_tc(s, 0);
891         esp_dma_ti_check(s);
892     } else {
893         /*
894          * Transfer truncated: raise INTR_BS to indicate early change of
895          * phase
896          */
897         s->rregs[ESP_RINTR] |= INTR_BS;
898         esp_raise_irq(s);
899         s->ti_size = 0;
900     }
901 
902     if (s->current_req) {
903         scsi_req_unref(s->current_req);
904         s->current_req = NULL;
905         s->current_dev = NULL;
906     }
907 }
908 
909 void esp_transfer_data(SCSIRequest *req, uint32_t len)
910 {
911     ESPState *s = req->hba_private;
912     int to_device = ((s->rregs[ESP_RSTAT] & 7) == STAT_DO);
913     uint32_t dmalen = esp_get_tc(s);
914 
915     assert(!s->do_cmd);
916     trace_esp_transfer_data(dmalen, s->ti_size);
917     s->async_len = len;
918     s->async_buf = scsi_req_get_buf(req);
919 
920     if (!to_device && !s->data_in_ready) {
921         /*
922          * Initial incoming data xfer is complete so raise command
923          * completion interrupt
924          */
925         s->data_in_ready = true;
926         s->rregs[ESP_RINTR] |= INTR_BS;
927         esp_raise_irq(s);
928     }
929 
930     /*
931      * Always perform the initial transfer upon reception of the next TI
932      * command to ensure the DMA/non-DMA status of the command is correct.
933      * It is not possible to use s->dma directly in the section below as
934      * some OSs send non-DMA NOP commands after a DMA transfer. Hence if the
935      * async data transfer is delayed then s->dma is set incorrectly.
936      */
937 
938     if (s->ti_cmd == (CMD_TI | CMD_DMA)) {
939         /* When the SCSI layer returns more data, raise deferred INTR_BS */
940         esp_dma_ti_check(s);
941 
942         esp_do_dma(s);
943     } else if (s->ti_cmd == CMD_TI) {
944         esp_do_nodma(s);
945     }
946 }
947 
948 static void handle_ti(ESPState *s)
949 {
950     uint32_t dmalen;
951 
952     if (s->dma && !s->dma_enabled) {
953         s->dma_cb = handle_ti;
954         return;
955     }
956 
957     s->ti_cmd = s->rregs[ESP_CMD];
958     if (s->dma) {
959         dmalen = esp_get_tc(s);
960         trace_esp_handle_ti(dmalen);
961         esp_do_dma(s);
962     } else {
963         trace_esp_handle_ti(s->ti_size);
964         esp_do_nodma(s);
965     }
966 }
967 
968 void esp_hard_reset(ESPState *s)
969 {
970     memset(s->rregs, 0, ESP_REGS);
971     memset(s->wregs, 0, ESP_REGS);
972     s->tchi_written = 0;
973     s->ti_size = 0;
974     s->async_len = 0;
975     fifo8_reset(&s->fifo);
976     fifo8_reset(&s->cmdfifo);
977     s->dma = 0;
978     s->do_cmd = 0;
979     s->dma_cb = NULL;
980 
981     s->rregs[ESP_CFG1] = 7;
982 }
983 
984 static void esp_soft_reset(ESPState *s)
985 {
986     qemu_irq_lower(s->irq);
987     qemu_irq_lower(s->irq_data);
988     esp_hard_reset(s);
989 }
990 
991 static void esp_bus_reset(ESPState *s)
992 {
993     bus_cold_reset(BUS(&s->bus));
994 }
995 
996 static void parent_esp_reset(ESPState *s, int irq, int level)
997 {
998     if (level) {
999         esp_soft_reset(s);
1000     }
1001 }
1002 
1003 static void esp_run_cmd(ESPState *s)
1004 {
1005     uint8_t cmd = s->rregs[ESP_CMD];
1006 
1007     if (cmd & CMD_DMA) {
1008         s->dma = 1;
1009         /* Reload DMA counter.  */
1010         if (esp_get_stc(s) == 0) {
1011             esp_set_tc(s, 0x10000);
1012         } else {
1013             esp_set_tc(s, esp_get_stc(s));
1014         }
1015     } else {
1016         s->dma = 0;
1017     }
1018     switch (cmd & CMD_CMD) {
1019     case CMD_NOP:
1020         trace_esp_mem_writeb_cmd_nop(cmd);
1021         break;
1022     case CMD_FLUSH:
1023         trace_esp_mem_writeb_cmd_flush(cmd);
1024         fifo8_reset(&s->fifo);
1025         break;
1026     case CMD_RESET:
1027         trace_esp_mem_writeb_cmd_reset(cmd);
1028         esp_soft_reset(s);
1029         break;
1030     case CMD_BUSRESET:
1031         trace_esp_mem_writeb_cmd_bus_reset(cmd);
1032         esp_bus_reset(s);
1033         if (!(s->wregs[ESP_CFG1] & CFG1_RESREPT)) {
1034             s->rregs[ESP_RINTR] |= INTR_RST;
1035             esp_raise_irq(s);
1036         }
1037         break;
1038     case CMD_TI:
1039         trace_esp_mem_writeb_cmd_ti(cmd);
1040         handle_ti(s);
1041         break;
1042     case CMD_ICCS:
1043         trace_esp_mem_writeb_cmd_iccs(cmd);
1044         write_response(s);
1045         s->rregs[ESP_RINTR] |= INTR_FC;
1046         esp_set_phase(s, STAT_MI);
1047         break;
1048     case CMD_MSGACC:
1049         trace_esp_mem_writeb_cmd_msgacc(cmd);
1050         s->rregs[ESP_RINTR] |= INTR_DC;
1051         s->rregs[ESP_RSEQ] = 0;
1052         s->rregs[ESP_RFLAGS] = 0;
1053         esp_raise_irq(s);
1054         break;
1055     case CMD_PAD:
1056         trace_esp_mem_writeb_cmd_pad(cmd);
1057         s->rregs[ESP_RSTAT] = STAT_TC;
1058         s->rregs[ESP_RINTR] |= INTR_FC;
1059         s->rregs[ESP_RSEQ] = 0;
1060         break;
1061     case CMD_SATN:
1062         trace_esp_mem_writeb_cmd_satn(cmd);
1063         break;
1064     case CMD_RSTATN:
1065         trace_esp_mem_writeb_cmd_rstatn(cmd);
1066         break;
1067     case CMD_SEL:
1068         trace_esp_mem_writeb_cmd_sel(cmd);
1069         handle_s_without_atn(s);
1070         break;
1071     case CMD_SELATN:
1072         trace_esp_mem_writeb_cmd_selatn(cmd);
1073         handle_satn(s);
1074         break;
1075     case CMD_SELATNS:
1076         trace_esp_mem_writeb_cmd_selatns(cmd);
1077         handle_satn_stop(s);
1078         break;
1079     case CMD_ENSEL:
1080         trace_esp_mem_writeb_cmd_ensel(cmd);
1081         s->rregs[ESP_RINTR] = 0;
1082         break;
1083     case CMD_DISSEL:
1084         trace_esp_mem_writeb_cmd_dissel(cmd);
1085         s->rregs[ESP_RINTR] = 0;
1086         esp_raise_irq(s);
1087         break;
1088     default:
1089         trace_esp_error_unhandled_command(cmd);
1090         break;
1091     }
1092 }
1093 
1094 uint64_t esp_reg_read(ESPState *s, uint32_t saddr)
1095 {
1096     uint32_t val;
1097 
1098     switch (saddr) {
1099     case ESP_FIFO:
1100         if (s->dma_memory_read && s->dma_memory_write &&
1101                 (s->rregs[ESP_RSTAT] & STAT_PIO_MASK) == 0) {
1102             /* Data out.  */
1103             qemu_log_mask(LOG_UNIMP, "esp: PIO data read not implemented\n");
1104             s->rregs[ESP_FIFO] = 0;
1105         } else {
1106             if ((s->rregs[ESP_RSTAT] & 0x7) == STAT_DI) {
1107                 if (s->ti_size) {
1108                     esp_do_nodma(s);
1109                 } else {
1110                     /*
1111                      * The last byte of a non-DMA transfer has been read out
1112                      * of the FIFO so switch to status phase
1113                      */
1114                     esp_set_phase(s, STAT_ST);
1115                 }
1116             }
1117             s->rregs[ESP_FIFO] = esp_fifo_pop(&s->fifo);
1118         }
1119         val = s->rregs[ESP_FIFO];
1120         break;
1121     case ESP_RINTR:
1122         /*
1123          * Clear sequence step, interrupt register and all status bits
1124          * except TC
1125          */
1126         val = s->rregs[ESP_RINTR];
1127         s->rregs[ESP_RINTR] = 0;
1128         s->rregs[ESP_RSTAT] &= ~STAT_TC;
1129         /*
1130          * According to the datasheet ESP_RSEQ should be cleared, but as the
1131          * emulation currently defers information transfers to the next TI
1132          * command leave it for now so that pedantic guests such as the old
1133          * Linux 2.6 driver see the correct flags before the next SCSI phase
1134          * transition.
1135          *
1136          * s->rregs[ESP_RSEQ] = SEQ_0;
1137          */
1138         esp_lower_irq(s);
1139         break;
1140     case ESP_TCHI:
1141         /* Return the unique id if the value has never been written */
1142         if (!s->tchi_written) {
1143             val = s->chip_id;
1144         } else {
1145             val = s->rregs[saddr];
1146         }
1147         break;
1148      case ESP_RFLAGS:
1149         /* Bottom 5 bits indicate number of bytes in FIFO */
1150         val = fifo8_num_used(&s->fifo);
1151         break;
1152     default:
1153         val = s->rregs[saddr];
1154         break;
1155     }
1156 
1157     trace_esp_mem_readb(saddr, val);
1158     return val;
1159 }
1160 
1161 void esp_reg_write(ESPState *s, uint32_t saddr, uint64_t val)
1162 {
1163     trace_esp_mem_writeb(saddr, s->wregs[saddr], val);
1164     switch (saddr) {
1165     case ESP_TCHI:
1166         s->tchi_written = true;
1167         /* fall through */
1168     case ESP_TCLO:
1169     case ESP_TCMID:
1170         s->rregs[ESP_RSTAT] &= ~STAT_TC;
1171         break;
1172     case ESP_FIFO:
1173         if (s->do_cmd) {
1174             if (!fifo8_is_full(&s->fifo)) {
1175                 esp_fifo_push(&s->fifo, val);
1176                 esp_fifo_push(&s->cmdfifo, fifo8_pop(&s->fifo));
1177             }
1178 
1179             /*
1180              * If any unexpected message out/command phase data is
1181              * transferred using non-DMA, raise the interrupt
1182              */
1183             if (s->rregs[ESP_CMD] == CMD_TI) {
1184                 s->rregs[ESP_RINTR] |= INTR_BS;
1185                 esp_raise_irq(s);
1186             }
1187         } else {
1188             esp_fifo_push(&s->fifo, val);
1189         }
1190         break;
1191     case ESP_CMD:
1192         s->rregs[saddr] = val;
1193         esp_run_cmd(s);
1194         break;
1195     case ESP_WBUSID ... ESP_WSYNO:
1196         break;
1197     case ESP_CFG1:
1198     case ESP_CFG2: case ESP_CFG3:
1199     case ESP_RES3: case ESP_RES4:
1200         s->rregs[saddr] = val;
1201         break;
1202     case ESP_WCCF ... ESP_WTEST:
1203         break;
1204     default:
1205         trace_esp_error_invalid_write(val, saddr);
1206         return;
1207     }
1208     s->wregs[saddr] = val;
1209 }
1210 
1211 static bool esp_mem_accepts(void *opaque, hwaddr addr,
1212                             unsigned size, bool is_write,
1213                             MemTxAttrs attrs)
1214 {
1215     return (size == 1) || (is_write && size == 4);
1216 }
1217 
1218 static bool esp_is_before_version_5(void *opaque, int version_id)
1219 {
1220     ESPState *s = ESP(opaque);
1221 
1222     version_id = MIN(version_id, s->mig_version_id);
1223     return version_id < 5;
1224 }
1225 
1226 static bool esp_is_version_5(void *opaque, int version_id)
1227 {
1228     ESPState *s = ESP(opaque);
1229 
1230     version_id = MIN(version_id, s->mig_version_id);
1231     return version_id >= 5;
1232 }
1233 
1234 static bool esp_is_version_6(void *opaque, int version_id)
1235 {
1236     ESPState *s = ESP(opaque);
1237 
1238     version_id = MIN(version_id, s->mig_version_id);
1239     return version_id >= 6;
1240 }
1241 
1242 int esp_pre_save(void *opaque)
1243 {
1244     ESPState *s = ESP(object_resolve_path_component(
1245                       OBJECT(opaque), "esp"));
1246 
1247     s->mig_version_id = vmstate_esp.version_id;
1248     return 0;
1249 }
1250 
1251 static int esp_post_load(void *opaque, int version_id)
1252 {
1253     ESPState *s = ESP(opaque);
1254     int len, i;
1255 
1256     version_id = MIN(version_id, s->mig_version_id);
1257 
1258     if (version_id < 5) {
1259         esp_set_tc(s, s->mig_dma_left);
1260 
1261         /* Migrate ti_buf to fifo */
1262         len = s->mig_ti_wptr - s->mig_ti_rptr;
1263         for (i = 0; i < len; i++) {
1264             fifo8_push(&s->fifo, s->mig_ti_buf[i]);
1265         }
1266 
1267         /* Migrate cmdbuf to cmdfifo */
1268         for (i = 0; i < s->mig_cmdlen; i++) {
1269             fifo8_push(&s->cmdfifo, s->mig_cmdbuf[i]);
1270         }
1271     }
1272 
1273     s->mig_version_id = vmstate_esp.version_id;
1274     return 0;
1275 }
1276 
1277 /*
1278  * PDMA (or pseudo-DMA) is only used on the Macintosh and requires the
1279  * guest CPU to perform the transfers between the SCSI bus and memory
1280  * itself. This is indicated by the dma_memory_read and dma_memory_write
1281  * functions being NULL (in contrast to the ESP PCI device) whilst
1282  * dma_enabled is still set.
1283  */
1284 
1285 static bool esp_pdma_needed(void *opaque)
1286 {
1287     ESPState *s = ESP(opaque);
1288 
1289     return s->dma_memory_read == NULL && s->dma_memory_write == NULL &&
1290            s->dma_enabled;
1291 }
1292 
1293 static const VMStateDescription vmstate_esp_pdma = {
1294     .name = "esp/pdma",
1295     .version_id = 0,
1296     .minimum_version_id = 0,
1297     .needed = esp_pdma_needed,
1298     .fields = (const VMStateField[]) {
1299         VMSTATE_UINT8(pdma_cb, ESPState),
1300         VMSTATE_END_OF_LIST()
1301     }
1302 };
1303 
1304 const VMStateDescription vmstate_esp = {
1305     .name = "esp",
1306     .version_id = 6,
1307     .minimum_version_id = 3,
1308     .post_load = esp_post_load,
1309     .fields = (const VMStateField[]) {
1310         VMSTATE_BUFFER(rregs, ESPState),
1311         VMSTATE_BUFFER(wregs, ESPState),
1312         VMSTATE_INT32(ti_size, ESPState),
1313         VMSTATE_UINT32_TEST(mig_ti_rptr, ESPState, esp_is_before_version_5),
1314         VMSTATE_UINT32_TEST(mig_ti_wptr, ESPState, esp_is_before_version_5),
1315         VMSTATE_BUFFER_TEST(mig_ti_buf, ESPState, esp_is_before_version_5),
1316         VMSTATE_UINT32(status, ESPState),
1317         VMSTATE_UINT32_TEST(mig_deferred_status, ESPState,
1318                             esp_is_before_version_5),
1319         VMSTATE_BOOL_TEST(mig_deferred_complete, ESPState,
1320                           esp_is_before_version_5),
1321         VMSTATE_UINT32(dma, ESPState),
1322         VMSTATE_STATIC_BUFFER(mig_cmdbuf, ESPState, 0,
1323                               esp_is_before_version_5, 0, 16),
1324         VMSTATE_STATIC_BUFFER(mig_cmdbuf, ESPState, 4,
1325                               esp_is_before_version_5, 16,
1326                               sizeof(typeof_field(ESPState, mig_cmdbuf))),
1327         VMSTATE_UINT32_TEST(mig_cmdlen, ESPState, esp_is_before_version_5),
1328         VMSTATE_UINT32(do_cmd, ESPState),
1329         VMSTATE_UINT32_TEST(mig_dma_left, ESPState, esp_is_before_version_5),
1330         VMSTATE_BOOL_TEST(data_in_ready, ESPState, esp_is_version_5),
1331         VMSTATE_UINT8_TEST(cmdfifo_cdb_offset, ESPState, esp_is_version_5),
1332         VMSTATE_FIFO8_TEST(fifo, ESPState, esp_is_version_5),
1333         VMSTATE_FIFO8_TEST(cmdfifo, ESPState, esp_is_version_5),
1334         VMSTATE_UINT8_TEST(ti_cmd, ESPState, esp_is_version_5),
1335         VMSTATE_UINT8_TEST(lun, ESPState, esp_is_version_6),
1336         VMSTATE_END_OF_LIST()
1337     },
1338     .subsections = (const VMStateDescription * const []) {
1339         &vmstate_esp_pdma,
1340         NULL
1341     }
1342 };
1343 
1344 static void sysbus_esp_mem_write(void *opaque, hwaddr addr,
1345                                  uint64_t val, unsigned int size)
1346 {
1347     SysBusESPState *sysbus = opaque;
1348     ESPState *s = ESP(&sysbus->esp);
1349     uint32_t saddr;
1350 
1351     saddr = addr >> sysbus->it_shift;
1352     esp_reg_write(s, saddr, val);
1353 }
1354 
1355 static uint64_t sysbus_esp_mem_read(void *opaque, hwaddr addr,
1356                                     unsigned int size)
1357 {
1358     SysBusESPState *sysbus = opaque;
1359     ESPState *s = ESP(&sysbus->esp);
1360     uint32_t saddr;
1361 
1362     saddr = addr >> sysbus->it_shift;
1363     return esp_reg_read(s, saddr);
1364 }
1365 
1366 static const MemoryRegionOps sysbus_esp_mem_ops = {
1367     .read = sysbus_esp_mem_read,
1368     .write = sysbus_esp_mem_write,
1369     .endianness = DEVICE_NATIVE_ENDIAN,
1370     .valid.accepts = esp_mem_accepts,
1371 };
1372 
1373 static void sysbus_esp_pdma_write(void *opaque, hwaddr addr,
1374                                   uint64_t val, unsigned int size)
1375 {
1376     SysBusESPState *sysbus = opaque;
1377     ESPState *s = ESP(&sysbus->esp);
1378 
1379     trace_esp_pdma_write(size);
1380 
1381     switch (size) {
1382     case 1:
1383         esp_pdma_write(s, val);
1384         break;
1385     case 2:
1386         esp_pdma_write(s, val >> 8);
1387         esp_pdma_write(s, val);
1388         break;
1389     }
1390     esp_pdma_cb(s);
1391 }
1392 
1393 static uint64_t sysbus_esp_pdma_read(void *opaque, hwaddr addr,
1394                                      unsigned int size)
1395 {
1396     SysBusESPState *sysbus = opaque;
1397     ESPState *s = ESP(&sysbus->esp);
1398     uint64_t val = 0;
1399 
1400     trace_esp_pdma_read(size);
1401 
1402     switch (size) {
1403     case 1:
1404         val = esp_pdma_read(s);
1405         break;
1406     case 2:
1407         val = esp_pdma_read(s);
1408         val = (val << 8) | esp_pdma_read(s);
1409         break;
1410     }
1411     esp_pdma_cb(s);
1412     return val;
1413 }
1414 
1415 static void *esp_load_request(QEMUFile *f, SCSIRequest *req)
1416 {
1417     ESPState *s = container_of(req->bus, ESPState, bus);
1418 
1419     scsi_req_ref(req);
1420     s->current_req = req;
1421     return s;
1422 }
1423 
1424 static const MemoryRegionOps sysbus_esp_pdma_ops = {
1425     .read = sysbus_esp_pdma_read,
1426     .write = sysbus_esp_pdma_write,
1427     .endianness = DEVICE_NATIVE_ENDIAN,
1428     .valid.min_access_size = 1,
1429     .valid.max_access_size = 4,
1430     .impl.min_access_size = 1,
1431     .impl.max_access_size = 2,
1432 };
1433 
1434 static const struct SCSIBusInfo esp_scsi_info = {
1435     .tcq = false,
1436     .max_target = ESP_MAX_DEVS,
1437     .max_lun = 7,
1438 
1439     .load_request = esp_load_request,
1440     .transfer_data = esp_transfer_data,
1441     .complete = esp_command_complete,
1442     .cancel = esp_request_cancelled
1443 };
1444 
1445 static void sysbus_esp_gpio_demux(void *opaque, int irq, int level)
1446 {
1447     SysBusESPState *sysbus = SYSBUS_ESP(opaque);
1448     ESPState *s = ESP(&sysbus->esp);
1449 
1450     switch (irq) {
1451     case 0:
1452         parent_esp_reset(s, irq, level);
1453         break;
1454     case 1:
1455         esp_dma_enable(s, irq, level);
1456         break;
1457     }
1458 }
1459 
1460 static void sysbus_esp_realize(DeviceState *dev, Error **errp)
1461 {
1462     SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
1463     SysBusESPState *sysbus = SYSBUS_ESP(dev);
1464     ESPState *s = ESP(&sysbus->esp);
1465 
1466     if (!qdev_realize(DEVICE(s), NULL, errp)) {
1467         return;
1468     }
1469 
1470     sysbus_init_irq(sbd, &s->irq);
1471     sysbus_init_irq(sbd, &s->irq_data);
1472     assert(sysbus->it_shift != -1);
1473 
1474     s->chip_id = TCHI_FAS100A;
1475     memory_region_init_io(&sysbus->iomem, OBJECT(sysbus), &sysbus_esp_mem_ops,
1476                           sysbus, "esp-regs", ESP_REGS << sysbus->it_shift);
1477     sysbus_init_mmio(sbd, &sysbus->iomem);
1478     memory_region_init_io(&sysbus->pdma, OBJECT(sysbus), &sysbus_esp_pdma_ops,
1479                           sysbus, "esp-pdma", 4);
1480     sysbus_init_mmio(sbd, &sysbus->pdma);
1481 
1482     qdev_init_gpio_in(dev, sysbus_esp_gpio_demux, 2);
1483 
1484     scsi_bus_init(&s->bus, sizeof(s->bus), dev, &esp_scsi_info);
1485 }
1486 
1487 static void sysbus_esp_hard_reset(DeviceState *dev)
1488 {
1489     SysBusESPState *sysbus = SYSBUS_ESP(dev);
1490     ESPState *s = ESP(&sysbus->esp);
1491 
1492     esp_hard_reset(s);
1493 }
1494 
1495 static void sysbus_esp_init(Object *obj)
1496 {
1497     SysBusESPState *sysbus = SYSBUS_ESP(obj);
1498 
1499     object_initialize_child(obj, "esp", &sysbus->esp, TYPE_ESP);
1500 }
1501 
1502 static const VMStateDescription vmstate_sysbus_esp_scsi = {
1503     .name = "sysbusespscsi",
1504     .version_id = 2,
1505     .minimum_version_id = 1,
1506     .pre_save = esp_pre_save,
1507     .fields = (const VMStateField[]) {
1508         VMSTATE_UINT8_V(esp.mig_version_id, SysBusESPState, 2),
1509         VMSTATE_STRUCT(esp, SysBusESPState, 0, vmstate_esp, ESPState),
1510         VMSTATE_END_OF_LIST()
1511     }
1512 };
1513 
1514 static void sysbus_esp_class_init(ObjectClass *klass, void *data)
1515 {
1516     DeviceClass *dc = DEVICE_CLASS(klass);
1517 
1518     dc->realize = sysbus_esp_realize;
1519     dc->reset = sysbus_esp_hard_reset;
1520     dc->vmsd = &vmstate_sysbus_esp_scsi;
1521     set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
1522 }
1523 
1524 static const TypeInfo sysbus_esp_info = {
1525     .name          = TYPE_SYSBUS_ESP,
1526     .parent        = TYPE_SYS_BUS_DEVICE,
1527     .instance_init = sysbus_esp_init,
1528     .instance_size = sizeof(SysBusESPState),
1529     .class_init    = sysbus_esp_class_init,
1530 };
1531 
1532 static void esp_finalize(Object *obj)
1533 {
1534     ESPState *s = ESP(obj);
1535 
1536     fifo8_destroy(&s->fifo);
1537     fifo8_destroy(&s->cmdfifo);
1538 }
1539 
1540 static void esp_init(Object *obj)
1541 {
1542     ESPState *s = ESP(obj);
1543 
1544     fifo8_create(&s->fifo, ESP_FIFO_SZ);
1545     fifo8_create(&s->cmdfifo, ESP_CMDFIFO_SZ);
1546 }
1547 
1548 static void esp_class_init(ObjectClass *klass, void *data)
1549 {
1550     DeviceClass *dc = DEVICE_CLASS(klass);
1551 
1552     /* internal device for sysbusesp/pciespscsi, not user-creatable */
1553     dc->user_creatable = false;
1554     set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
1555 }
1556 
1557 static const TypeInfo esp_info = {
1558     .name = TYPE_ESP,
1559     .parent = TYPE_DEVICE,
1560     .instance_init = esp_init,
1561     .instance_finalize = esp_finalize,
1562     .instance_size = sizeof(ESPState),
1563     .class_init = esp_class_init,
1564 };
1565 
1566 static void esp_register_types(void)
1567 {
1568     type_register_static(&sysbus_esp_info);
1569     type_register_static(&esp_info);
1570 }
1571 
1572 type_init(esp_register_types)
1573