xref: /qemu/hw/scsi/esp.c (revision 19e9afb1a3d905f9892bb696e156f4524f2cbbf6)
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             esp_set_pdma_cb(s, DO_DMA_PDMA_CB);
660             esp_raise_drq(s);
661             return;
662         }
663         trace_esp_handle_ti_cmd(cmdlen);
664         s->ti_size = 0;
665         if ((s->rregs[ESP_RSTAT] & 7) == STAT_CD) {
666             /* No command received */
667             if (s->cmdfifo_cdb_offset == fifo8_num_used(&s->cmdfifo)) {
668                 return;
669             }
670 
671             /* Command has been received */
672             s->do_cmd = 0;
673             do_cmd(s);
674         } else {
675             /*
676              * Extra message out bytes received: update cmdfifo_cdb_offset
677              * and then switch to command phase
678              */
679             s->cmdfifo_cdb_offset = fifo8_num_used(&s->cmdfifo);
680             esp_set_phase(s, STAT_CD);
681             s->rregs[ESP_RSEQ] = SEQ_CD;
682             s->rregs[ESP_RINTR] |= INTR_BS;
683             esp_raise_irq(s);
684         }
685         return;
686     }
687     if (!s->current_req) {
688         return;
689     }
690     if (s->async_len == 0) {
691         /* Defer until data is available.  */
692         return;
693     }
694     if (len > s->async_len) {
695         len = s->async_len;
696     }
697     if (to_device) {
698         if (s->dma_memory_read) {
699             s->dma_memory_read(s->dma_opaque, s->async_buf, len);
700 
701             esp_set_tc(s, esp_get_tc(s) - len);
702             s->async_buf += len;
703             s->async_len -= len;
704             s->ti_size += len;
705 
706             if (s->async_len == 0 && fifo8_num_used(&s->fifo) < 2) {
707                 /* Defer until the scsi layer has completed */
708                 scsi_req_continue(s->current_req);
709                 return;
710             }
711 
712             esp_dma_ti_check(s);
713         } else {
714             /* Copy FIFO data to device */
715             len = MIN(s->async_len, ESP_FIFO_SZ);
716             len = MIN(len, fifo8_num_used(&s->fifo));
717             n = esp_fifo_pop_buf(&s->fifo, s->async_buf, len);
718             s->async_buf += n;
719             s->async_len -= n;
720             s->ti_size += n;
721 
722             esp_set_pdma_cb(s, DO_DMA_PDMA_CB);
723             esp_raise_drq(s);
724 
725             if (s->async_len == 0 && fifo8_num_used(&s->fifo) < 2) {
726                 /* Defer until the scsi layer has completed */
727                 scsi_req_continue(s->current_req);
728                 return;
729             }
730 
731             esp_dma_ti_check(s);
732         }
733     } else {
734         if (s->dma_memory_write) {
735             s->dma_memory_write(s->dma_opaque, s->async_buf, len);
736 
737             esp_set_tc(s, esp_get_tc(s) - len);
738             s->async_buf += len;
739             s->async_len -= len;
740             s->ti_size -= len;
741 
742             if (s->async_len == 0 && fifo8_num_used(&s->fifo) < 2) {
743                 /* Defer until the scsi layer has completed */
744                 scsi_req_continue(s->current_req);
745                 return;
746             }
747 
748             esp_dma_ti_check(s);
749         } else {
750             /* Copy device data to FIFO */
751             len = MIN(len, fifo8_num_free(&s->fifo));
752             fifo8_push_all(&s->fifo, s->async_buf, len);
753             s->async_buf += len;
754             s->async_len -= len;
755             s->ti_size -= len;
756             esp_set_tc(s, esp_get_tc(s) - len);
757             esp_set_pdma_cb(s, DO_DMA_PDMA_CB);
758             esp_raise_drq(s);
759 
760             if (s->async_len == 0 && fifo8_num_used(&s->fifo) < 2) {
761                 /* Defer until the scsi layer has completed */
762                 scsi_req_continue(s->current_req);
763                 return;
764             }
765 
766             esp_dma_ti_check(s);
767         }
768     }
769 }
770 
771 static void esp_do_nodma(ESPState *s)
772 {
773     int to_device = ((s->rregs[ESP_RSTAT] & 7) == STAT_DO);
774     uint8_t buf[ESP_FIFO_SZ];
775     uint32_t cmdlen;
776     int len, n;
777 
778     if (s->do_cmd) {
779         /* Copy FIFO into cmdfifo */
780         n = esp_fifo_pop_buf(&s->fifo, buf, fifo8_num_used(&s->fifo));
781         n = MIN(fifo8_num_free(&s->cmdfifo), n);
782         fifo8_push_all(&s->cmdfifo, buf, n);
783 
784         cmdlen = fifo8_num_used(&s->cmdfifo);
785         trace_esp_handle_ti_cmd(cmdlen);
786         s->ti_size = 0;
787         if ((s->rregs[ESP_RSTAT] & 7) == STAT_CD) {
788             /* No command received */
789             if (s->cmdfifo_cdb_offset == fifo8_num_used(&s->cmdfifo)) {
790                 return;
791             }
792 
793             /* Command has been received */
794             s->do_cmd = 0;
795             do_cmd(s);
796         } else {
797             /*
798              * Extra message out bytes received: update cmdfifo_cdb_offset
799              * and then switch to command phase
800              */
801             s->cmdfifo_cdb_offset = fifo8_num_used(&s->cmdfifo);
802             esp_set_phase(s, STAT_CD);
803             s->rregs[ESP_RSEQ] = SEQ_CD;
804             s->rregs[ESP_RINTR] |= INTR_BS;
805             esp_raise_irq(s);
806         }
807         return;
808     }
809 
810     if (!s->current_req) {
811         return;
812     }
813 
814     if (s->async_len == 0) {
815         /* Defer until data is available.  */
816         return;
817     }
818 
819     if (to_device) {
820         len = MIN(s->async_len, ESP_FIFO_SZ);
821         len = MIN(len, fifo8_num_used(&s->fifo));
822         esp_fifo_pop_buf(&s->fifo, s->async_buf, len);
823         s->async_buf += len;
824         s->async_len -= len;
825         s->ti_size += len;
826     } else {
827         if (fifo8_is_empty(&s->fifo)) {
828             fifo8_push(&s->fifo, s->async_buf[0]);
829             s->async_buf++;
830             s->async_len--;
831             s->ti_size--;
832         }
833     }
834 
835     if (s->async_len == 0) {
836         scsi_req_continue(s->current_req);
837         return;
838     }
839 
840     s->rregs[ESP_RINTR] |= INTR_BS;
841     esp_raise_irq(s);
842 }
843 
844 static void esp_pdma_cb(ESPState *s)
845 {
846     switch (s->pdma_cb) {
847     case SATN_PDMA_CB:
848         satn_pdma_cb(s);
849         break;
850     case S_WITHOUT_SATN_PDMA_CB:
851         s_without_satn_pdma_cb(s);
852         break;
853     case SATN_STOP_PDMA_CB:
854         satn_stop_pdma_cb(s);
855         break;
856     case WRITE_RESPONSE_PDMA_CB:
857         write_response_pdma_cb(s);
858         break;
859     case DO_DMA_PDMA_CB:
860         do_dma_pdma_cb(s);
861         break;
862     default:
863         g_assert_not_reached();
864     }
865 }
866 
867 void esp_command_complete(SCSIRequest *req, size_t resid)
868 {
869     ESPState *s = req->hba_private;
870     int to_device = ((s->rregs[ESP_RSTAT] & 7) == STAT_DO);
871 
872     trace_esp_command_complete();
873 
874     /*
875      * Non-DMA transfers from the target will leave the last byte in
876      * the FIFO so don't reset ti_size in this case
877      */
878     if (s->dma || to_device) {
879         if (s->ti_size != 0) {
880             trace_esp_command_complete_unexpected();
881         }
882     }
883 
884     s->async_len = 0;
885     if (req->status) {
886         trace_esp_command_complete_fail();
887     }
888     s->status = req->status;
889 
890     /*
891      * Switch to status phase. For non-DMA transfers from the target the last
892      * byte is still in the FIFO
893      */
894     esp_set_phase(s, STAT_ST);
895     if (s->ti_size == 0) {
896         /*
897          * Transfer complete: force TC to zero just in case a TI command was
898          * requested for more data than the command returns (Solaris 8 does
899          * this)
900          */
901         esp_set_tc(s, 0);
902         esp_dma_ti_check(s);
903     } else {
904         /*
905          * Transfer truncated: raise INTR_BS to indicate early change of
906          * phase
907          */
908         s->rregs[ESP_RINTR] |= INTR_BS;
909         esp_raise_irq(s);
910         s->ti_size = 0;
911     }
912 
913     if (s->current_req) {
914         scsi_req_unref(s->current_req);
915         s->current_req = NULL;
916         s->current_dev = NULL;
917     }
918 }
919 
920 void esp_transfer_data(SCSIRequest *req, uint32_t len)
921 {
922     ESPState *s = req->hba_private;
923     int to_device = ((s->rregs[ESP_RSTAT] & 7) == STAT_DO);
924     uint32_t dmalen = esp_get_tc(s);
925 
926     assert(!s->do_cmd);
927     trace_esp_transfer_data(dmalen, s->ti_size);
928     s->async_len = len;
929     s->async_buf = scsi_req_get_buf(req);
930 
931     if (!to_device && !s->data_in_ready) {
932         /*
933          * Initial incoming data xfer is complete so raise command
934          * completion interrupt
935          */
936         s->data_in_ready = true;
937         s->rregs[ESP_RINTR] |= INTR_BS;
938         esp_raise_irq(s);
939     }
940 
941     /*
942      * Always perform the initial transfer upon reception of the next TI
943      * command to ensure the DMA/non-DMA status of the command is correct.
944      * It is not possible to use s->dma directly in the section below as
945      * some OSs send non-DMA NOP commands after a DMA transfer. Hence if the
946      * async data transfer is delayed then s->dma is set incorrectly.
947      */
948 
949     if (s->ti_cmd == (CMD_TI | CMD_DMA)) {
950         /* When the SCSI layer returns more data, raise deferred INTR_BS */
951         esp_dma_ti_check(s);
952 
953         esp_do_dma(s);
954     } else if (s->ti_cmd == CMD_TI) {
955         esp_do_nodma(s);
956     }
957 }
958 
959 static void handle_ti(ESPState *s)
960 {
961     uint32_t dmalen;
962 
963     if (s->dma && !s->dma_enabled) {
964         s->dma_cb = handle_ti;
965         return;
966     }
967 
968     s->ti_cmd = s->rregs[ESP_CMD];
969     if (s->dma) {
970         dmalen = esp_get_tc(s);
971         trace_esp_handle_ti(dmalen);
972         esp_do_dma(s);
973     } else {
974         trace_esp_handle_ti(s->ti_size);
975         esp_do_nodma(s);
976     }
977 }
978 
979 void esp_hard_reset(ESPState *s)
980 {
981     memset(s->rregs, 0, ESP_REGS);
982     memset(s->wregs, 0, ESP_REGS);
983     s->tchi_written = 0;
984     s->ti_size = 0;
985     s->async_len = 0;
986     fifo8_reset(&s->fifo);
987     fifo8_reset(&s->cmdfifo);
988     s->dma = 0;
989     s->do_cmd = 0;
990     s->dma_cb = NULL;
991 
992     s->rregs[ESP_CFG1] = 7;
993 }
994 
995 static void esp_soft_reset(ESPState *s)
996 {
997     qemu_irq_lower(s->irq);
998     qemu_irq_lower(s->irq_data);
999     esp_hard_reset(s);
1000 }
1001 
1002 static void esp_bus_reset(ESPState *s)
1003 {
1004     bus_cold_reset(BUS(&s->bus));
1005 }
1006 
1007 static void parent_esp_reset(ESPState *s, int irq, int level)
1008 {
1009     if (level) {
1010         esp_soft_reset(s);
1011     }
1012 }
1013 
1014 static void esp_run_cmd(ESPState *s)
1015 {
1016     uint8_t cmd = s->rregs[ESP_CMD];
1017 
1018     if (cmd & CMD_DMA) {
1019         s->dma = 1;
1020         /* Reload DMA counter.  */
1021         if (esp_get_stc(s) == 0) {
1022             esp_set_tc(s, 0x10000);
1023         } else {
1024             esp_set_tc(s, esp_get_stc(s));
1025         }
1026     } else {
1027         s->dma = 0;
1028     }
1029     switch (cmd & CMD_CMD) {
1030     case CMD_NOP:
1031         trace_esp_mem_writeb_cmd_nop(cmd);
1032         break;
1033     case CMD_FLUSH:
1034         trace_esp_mem_writeb_cmd_flush(cmd);
1035         fifo8_reset(&s->fifo);
1036         break;
1037     case CMD_RESET:
1038         trace_esp_mem_writeb_cmd_reset(cmd);
1039         esp_soft_reset(s);
1040         break;
1041     case CMD_BUSRESET:
1042         trace_esp_mem_writeb_cmd_bus_reset(cmd);
1043         esp_bus_reset(s);
1044         if (!(s->wregs[ESP_CFG1] & CFG1_RESREPT)) {
1045             s->rregs[ESP_RINTR] |= INTR_RST;
1046             esp_raise_irq(s);
1047         }
1048         break;
1049     case CMD_TI:
1050         trace_esp_mem_writeb_cmd_ti(cmd);
1051         handle_ti(s);
1052         break;
1053     case CMD_ICCS:
1054         trace_esp_mem_writeb_cmd_iccs(cmd);
1055         write_response(s);
1056         s->rregs[ESP_RINTR] |= INTR_FC;
1057         esp_set_phase(s, STAT_MI);
1058         break;
1059     case CMD_MSGACC:
1060         trace_esp_mem_writeb_cmd_msgacc(cmd);
1061         s->rregs[ESP_RINTR] |= INTR_DC;
1062         s->rregs[ESP_RSEQ] = 0;
1063         s->rregs[ESP_RFLAGS] = 0;
1064         esp_raise_irq(s);
1065         break;
1066     case CMD_PAD:
1067         trace_esp_mem_writeb_cmd_pad(cmd);
1068         s->rregs[ESP_RSTAT] = STAT_TC;
1069         s->rregs[ESP_RINTR] |= INTR_FC;
1070         s->rregs[ESP_RSEQ] = 0;
1071         break;
1072     case CMD_SATN:
1073         trace_esp_mem_writeb_cmd_satn(cmd);
1074         break;
1075     case CMD_RSTATN:
1076         trace_esp_mem_writeb_cmd_rstatn(cmd);
1077         break;
1078     case CMD_SEL:
1079         trace_esp_mem_writeb_cmd_sel(cmd);
1080         handle_s_without_atn(s);
1081         break;
1082     case CMD_SELATN:
1083         trace_esp_mem_writeb_cmd_selatn(cmd);
1084         handle_satn(s);
1085         break;
1086     case CMD_SELATNS:
1087         trace_esp_mem_writeb_cmd_selatns(cmd);
1088         handle_satn_stop(s);
1089         break;
1090     case CMD_ENSEL:
1091         trace_esp_mem_writeb_cmd_ensel(cmd);
1092         s->rregs[ESP_RINTR] = 0;
1093         break;
1094     case CMD_DISSEL:
1095         trace_esp_mem_writeb_cmd_dissel(cmd);
1096         s->rregs[ESP_RINTR] = 0;
1097         esp_raise_irq(s);
1098         break;
1099     default:
1100         trace_esp_error_unhandled_command(cmd);
1101         break;
1102     }
1103 }
1104 
1105 uint64_t esp_reg_read(ESPState *s, uint32_t saddr)
1106 {
1107     uint32_t val;
1108 
1109     switch (saddr) {
1110     case ESP_FIFO:
1111         if (s->dma_memory_read && s->dma_memory_write &&
1112                 (s->rregs[ESP_RSTAT] & STAT_PIO_MASK) == 0) {
1113             /* Data out.  */
1114             qemu_log_mask(LOG_UNIMP, "esp: PIO data read not implemented\n");
1115             s->rregs[ESP_FIFO] = 0;
1116         } else {
1117             if ((s->rregs[ESP_RSTAT] & 0x7) == STAT_DI) {
1118                 if (s->ti_size) {
1119                     esp_do_nodma(s);
1120                 } else {
1121                     /*
1122                      * The last byte of a non-DMA transfer has been read out
1123                      * of the FIFO so switch to status phase
1124                      */
1125                     esp_set_phase(s, STAT_ST);
1126                 }
1127             }
1128             s->rregs[ESP_FIFO] = esp_fifo_pop(&s->fifo);
1129         }
1130         val = s->rregs[ESP_FIFO];
1131         break;
1132     case ESP_RINTR:
1133         /*
1134          * Clear sequence step, interrupt register and all status bits
1135          * except TC
1136          */
1137         val = s->rregs[ESP_RINTR];
1138         s->rregs[ESP_RINTR] = 0;
1139         s->rregs[ESP_RSTAT] &= ~STAT_TC;
1140         /*
1141          * According to the datasheet ESP_RSEQ should be cleared, but as the
1142          * emulation currently defers information transfers to the next TI
1143          * command leave it for now so that pedantic guests such as the old
1144          * Linux 2.6 driver see the correct flags before the next SCSI phase
1145          * transition.
1146          *
1147          * s->rregs[ESP_RSEQ] = SEQ_0;
1148          */
1149         esp_lower_irq(s);
1150         break;
1151     case ESP_TCHI:
1152         /* Return the unique id if the value has never been written */
1153         if (!s->tchi_written) {
1154             val = s->chip_id;
1155         } else {
1156             val = s->rregs[saddr];
1157         }
1158         break;
1159      case ESP_RFLAGS:
1160         /* Bottom 5 bits indicate number of bytes in FIFO */
1161         val = fifo8_num_used(&s->fifo);
1162         break;
1163     default:
1164         val = s->rregs[saddr];
1165         break;
1166     }
1167 
1168     trace_esp_mem_readb(saddr, val);
1169     return val;
1170 }
1171 
1172 void esp_reg_write(ESPState *s, uint32_t saddr, uint64_t val)
1173 {
1174     trace_esp_mem_writeb(saddr, s->wregs[saddr], val);
1175     switch (saddr) {
1176     case ESP_TCHI:
1177         s->tchi_written = true;
1178         /* fall through */
1179     case ESP_TCLO:
1180     case ESP_TCMID:
1181         s->rregs[ESP_RSTAT] &= ~STAT_TC;
1182         break;
1183     case ESP_FIFO:
1184         if (s->do_cmd) {
1185             if (!fifo8_is_full(&s->fifo)) {
1186                 esp_fifo_push(&s->fifo, val);
1187                 esp_fifo_push(&s->cmdfifo, fifo8_pop(&s->fifo));
1188             }
1189 
1190             /*
1191              * If any unexpected message out/command phase data is
1192              * transferred using non-DMA, raise the interrupt
1193              */
1194             if (s->rregs[ESP_CMD] == CMD_TI) {
1195                 s->rregs[ESP_RINTR] |= INTR_BS;
1196                 esp_raise_irq(s);
1197             }
1198         } else {
1199             esp_fifo_push(&s->fifo, val);
1200         }
1201         break;
1202     case ESP_CMD:
1203         s->rregs[saddr] = val;
1204         esp_run_cmd(s);
1205         break;
1206     case ESP_WBUSID ... ESP_WSYNO:
1207         break;
1208     case ESP_CFG1:
1209     case ESP_CFG2: case ESP_CFG3:
1210     case ESP_RES3: case ESP_RES4:
1211         s->rregs[saddr] = val;
1212         break;
1213     case ESP_WCCF ... ESP_WTEST:
1214         break;
1215     default:
1216         trace_esp_error_invalid_write(val, saddr);
1217         return;
1218     }
1219     s->wregs[saddr] = val;
1220 }
1221 
1222 static bool esp_mem_accepts(void *opaque, hwaddr addr,
1223                             unsigned size, bool is_write,
1224                             MemTxAttrs attrs)
1225 {
1226     return (size == 1) || (is_write && size == 4);
1227 }
1228 
1229 static bool esp_is_before_version_5(void *opaque, int version_id)
1230 {
1231     ESPState *s = ESP(opaque);
1232 
1233     version_id = MIN(version_id, s->mig_version_id);
1234     return version_id < 5;
1235 }
1236 
1237 static bool esp_is_version_5(void *opaque, int version_id)
1238 {
1239     ESPState *s = ESP(opaque);
1240 
1241     version_id = MIN(version_id, s->mig_version_id);
1242     return version_id >= 5;
1243 }
1244 
1245 static bool esp_is_version_6(void *opaque, int version_id)
1246 {
1247     ESPState *s = ESP(opaque);
1248 
1249     version_id = MIN(version_id, s->mig_version_id);
1250     return version_id >= 6;
1251 }
1252 
1253 int esp_pre_save(void *opaque)
1254 {
1255     ESPState *s = ESP(object_resolve_path_component(
1256                       OBJECT(opaque), "esp"));
1257 
1258     s->mig_version_id = vmstate_esp.version_id;
1259     return 0;
1260 }
1261 
1262 static int esp_post_load(void *opaque, int version_id)
1263 {
1264     ESPState *s = ESP(opaque);
1265     int len, i;
1266 
1267     version_id = MIN(version_id, s->mig_version_id);
1268 
1269     if (version_id < 5) {
1270         esp_set_tc(s, s->mig_dma_left);
1271 
1272         /* Migrate ti_buf to fifo */
1273         len = s->mig_ti_wptr - s->mig_ti_rptr;
1274         for (i = 0; i < len; i++) {
1275             fifo8_push(&s->fifo, s->mig_ti_buf[i]);
1276         }
1277 
1278         /* Migrate cmdbuf to cmdfifo */
1279         for (i = 0; i < s->mig_cmdlen; i++) {
1280             fifo8_push(&s->cmdfifo, s->mig_cmdbuf[i]);
1281         }
1282     }
1283 
1284     s->mig_version_id = vmstate_esp.version_id;
1285     return 0;
1286 }
1287 
1288 /*
1289  * PDMA (or pseudo-DMA) is only used on the Macintosh and requires the
1290  * guest CPU to perform the transfers between the SCSI bus and memory
1291  * itself. This is indicated by the dma_memory_read and dma_memory_write
1292  * functions being NULL (in contrast to the ESP PCI device) whilst
1293  * dma_enabled is still set.
1294  */
1295 
1296 static bool esp_pdma_needed(void *opaque)
1297 {
1298     ESPState *s = ESP(opaque);
1299 
1300     return s->dma_memory_read == NULL && s->dma_memory_write == NULL &&
1301            s->dma_enabled;
1302 }
1303 
1304 static const VMStateDescription vmstate_esp_pdma = {
1305     .name = "esp/pdma",
1306     .version_id = 0,
1307     .minimum_version_id = 0,
1308     .needed = esp_pdma_needed,
1309     .fields = (const VMStateField[]) {
1310         VMSTATE_UINT8(pdma_cb, ESPState),
1311         VMSTATE_END_OF_LIST()
1312     }
1313 };
1314 
1315 const VMStateDescription vmstate_esp = {
1316     .name = "esp",
1317     .version_id = 6,
1318     .minimum_version_id = 3,
1319     .post_load = esp_post_load,
1320     .fields = (const VMStateField[]) {
1321         VMSTATE_BUFFER(rregs, ESPState),
1322         VMSTATE_BUFFER(wregs, ESPState),
1323         VMSTATE_INT32(ti_size, ESPState),
1324         VMSTATE_UINT32_TEST(mig_ti_rptr, ESPState, esp_is_before_version_5),
1325         VMSTATE_UINT32_TEST(mig_ti_wptr, ESPState, esp_is_before_version_5),
1326         VMSTATE_BUFFER_TEST(mig_ti_buf, ESPState, esp_is_before_version_5),
1327         VMSTATE_UINT32(status, ESPState),
1328         VMSTATE_UINT32_TEST(mig_deferred_status, ESPState,
1329                             esp_is_before_version_5),
1330         VMSTATE_BOOL_TEST(mig_deferred_complete, ESPState,
1331                           esp_is_before_version_5),
1332         VMSTATE_UINT32(dma, ESPState),
1333         VMSTATE_STATIC_BUFFER(mig_cmdbuf, ESPState, 0,
1334                               esp_is_before_version_5, 0, 16),
1335         VMSTATE_STATIC_BUFFER(mig_cmdbuf, ESPState, 4,
1336                               esp_is_before_version_5, 16,
1337                               sizeof(typeof_field(ESPState, mig_cmdbuf))),
1338         VMSTATE_UINT32_TEST(mig_cmdlen, ESPState, esp_is_before_version_5),
1339         VMSTATE_UINT32(do_cmd, ESPState),
1340         VMSTATE_UINT32_TEST(mig_dma_left, ESPState, esp_is_before_version_5),
1341         VMSTATE_BOOL_TEST(data_in_ready, ESPState, esp_is_version_5),
1342         VMSTATE_UINT8_TEST(cmdfifo_cdb_offset, ESPState, esp_is_version_5),
1343         VMSTATE_FIFO8_TEST(fifo, ESPState, esp_is_version_5),
1344         VMSTATE_FIFO8_TEST(cmdfifo, ESPState, esp_is_version_5),
1345         VMSTATE_UINT8_TEST(ti_cmd, ESPState, esp_is_version_5),
1346         VMSTATE_UINT8_TEST(lun, ESPState, esp_is_version_6),
1347         VMSTATE_END_OF_LIST()
1348     },
1349     .subsections = (const VMStateDescription * const []) {
1350         &vmstate_esp_pdma,
1351         NULL
1352     }
1353 };
1354 
1355 static void sysbus_esp_mem_write(void *opaque, hwaddr addr,
1356                                  uint64_t val, 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     esp_reg_write(s, saddr, val);
1364 }
1365 
1366 static uint64_t sysbus_esp_mem_read(void *opaque, hwaddr addr,
1367                                     unsigned int size)
1368 {
1369     SysBusESPState *sysbus = opaque;
1370     ESPState *s = ESP(&sysbus->esp);
1371     uint32_t saddr;
1372 
1373     saddr = addr >> sysbus->it_shift;
1374     return esp_reg_read(s, saddr);
1375 }
1376 
1377 static const MemoryRegionOps sysbus_esp_mem_ops = {
1378     .read = sysbus_esp_mem_read,
1379     .write = sysbus_esp_mem_write,
1380     .endianness = DEVICE_NATIVE_ENDIAN,
1381     .valid.accepts = esp_mem_accepts,
1382 };
1383 
1384 static void sysbus_esp_pdma_write(void *opaque, hwaddr addr,
1385                                   uint64_t val, unsigned int size)
1386 {
1387     SysBusESPState *sysbus = opaque;
1388     ESPState *s = ESP(&sysbus->esp);
1389 
1390     trace_esp_pdma_write(size);
1391 
1392     switch (size) {
1393     case 1:
1394         esp_pdma_write(s, val);
1395         break;
1396     case 2:
1397         esp_pdma_write(s, val >> 8);
1398         esp_pdma_write(s, val);
1399         break;
1400     }
1401     esp_pdma_cb(s);
1402 }
1403 
1404 static uint64_t sysbus_esp_pdma_read(void *opaque, hwaddr addr,
1405                                      unsigned int size)
1406 {
1407     SysBusESPState *sysbus = opaque;
1408     ESPState *s = ESP(&sysbus->esp);
1409     uint64_t val = 0;
1410 
1411     trace_esp_pdma_read(size);
1412 
1413     switch (size) {
1414     case 1:
1415         val = esp_pdma_read(s);
1416         break;
1417     case 2:
1418         val = esp_pdma_read(s);
1419         val = (val << 8) | esp_pdma_read(s);
1420         break;
1421     }
1422     esp_pdma_cb(s);
1423     return val;
1424 }
1425 
1426 static void *esp_load_request(QEMUFile *f, SCSIRequest *req)
1427 {
1428     ESPState *s = container_of(req->bus, ESPState, bus);
1429 
1430     scsi_req_ref(req);
1431     s->current_req = req;
1432     return s;
1433 }
1434 
1435 static const MemoryRegionOps sysbus_esp_pdma_ops = {
1436     .read = sysbus_esp_pdma_read,
1437     .write = sysbus_esp_pdma_write,
1438     .endianness = DEVICE_NATIVE_ENDIAN,
1439     .valid.min_access_size = 1,
1440     .valid.max_access_size = 4,
1441     .impl.min_access_size = 1,
1442     .impl.max_access_size = 2,
1443 };
1444 
1445 static const struct SCSIBusInfo esp_scsi_info = {
1446     .tcq = false,
1447     .max_target = ESP_MAX_DEVS,
1448     .max_lun = 7,
1449 
1450     .load_request = esp_load_request,
1451     .transfer_data = esp_transfer_data,
1452     .complete = esp_command_complete,
1453     .cancel = esp_request_cancelled
1454 };
1455 
1456 static void sysbus_esp_gpio_demux(void *opaque, int irq, int level)
1457 {
1458     SysBusESPState *sysbus = SYSBUS_ESP(opaque);
1459     ESPState *s = ESP(&sysbus->esp);
1460 
1461     switch (irq) {
1462     case 0:
1463         parent_esp_reset(s, irq, level);
1464         break;
1465     case 1:
1466         esp_dma_enable(s, irq, level);
1467         break;
1468     }
1469 }
1470 
1471 static void sysbus_esp_realize(DeviceState *dev, Error **errp)
1472 {
1473     SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
1474     SysBusESPState *sysbus = SYSBUS_ESP(dev);
1475     ESPState *s = ESP(&sysbus->esp);
1476 
1477     if (!qdev_realize(DEVICE(s), NULL, errp)) {
1478         return;
1479     }
1480 
1481     sysbus_init_irq(sbd, &s->irq);
1482     sysbus_init_irq(sbd, &s->irq_data);
1483     assert(sysbus->it_shift != -1);
1484 
1485     s->chip_id = TCHI_FAS100A;
1486     memory_region_init_io(&sysbus->iomem, OBJECT(sysbus), &sysbus_esp_mem_ops,
1487                           sysbus, "esp-regs", ESP_REGS << sysbus->it_shift);
1488     sysbus_init_mmio(sbd, &sysbus->iomem);
1489     memory_region_init_io(&sysbus->pdma, OBJECT(sysbus), &sysbus_esp_pdma_ops,
1490                           sysbus, "esp-pdma", 4);
1491     sysbus_init_mmio(sbd, &sysbus->pdma);
1492 
1493     qdev_init_gpio_in(dev, sysbus_esp_gpio_demux, 2);
1494 
1495     scsi_bus_init(&s->bus, sizeof(s->bus), dev, &esp_scsi_info);
1496 }
1497 
1498 static void sysbus_esp_hard_reset(DeviceState *dev)
1499 {
1500     SysBusESPState *sysbus = SYSBUS_ESP(dev);
1501     ESPState *s = ESP(&sysbus->esp);
1502 
1503     esp_hard_reset(s);
1504 }
1505 
1506 static void sysbus_esp_init(Object *obj)
1507 {
1508     SysBusESPState *sysbus = SYSBUS_ESP(obj);
1509 
1510     object_initialize_child(obj, "esp", &sysbus->esp, TYPE_ESP);
1511 }
1512 
1513 static const VMStateDescription vmstate_sysbus_esp_scsi = {
1514     .name = "sysbusespscsi",
1515     .version_id = 2,
1516     .minimum_version_id = 1,
1517     .pre_save = esp_pre_save,
1518     .fields = (const VMStateField[]) {
1519         VMSTATE_UINT8_V(esp.mig_version_id, SysBusESPState, 2),
1520         VMSTATE_STRUCT(esp, SysBusESPState, 0, vmstate_esp, ESPState),
1521         VMSTATE_END_OF_LIST()
1522     }
1523 };
1524 
1525 static void sysbus_esp_class_init(ObjectClass *klass, void *data)
1526 {
1527     DeviceClass *dc = DEVICE_CLASS(klass);
1528 
1529     dc->realize = sysbus_esp_realize;
1530     dc->reset = sysbus_esp_hard_reset;
1531     dc->vmsd = &vmstate_sysbus_esp_scsi;
1532     set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
1533 }
1534 
1535 static const TypeInfo sysbus_esp_info = {
1536     .name          = TYPE_SYSBUS_ESP,
1537     .parent        = TYPE_SYS_BUS_DEVICE,
1538     .instance_init = sysbus_esp_init,
1539     .instance_size = sizeof(SysBusESPState),
1540     .class_init    = sysbus_esp_class_init,
1541 };
1542 
1543 static void esp_finalize(Object *obj)
1544 {
1545     ESPState *s = ESP(obj);
1546 
1547     fifo8_destroy(&s->fifo);
1548     fifo8_destroy(&s->cmdfifo);
1549 }
1550 
1551 static void esp_init(Object *obj)
1552 {
1553     ESPState *s = ESP(obj);
1554 
1555     fifo8_create(&s->fifo, ESP_FIFO_SZ);
1556     fifo8_create(&s->cmdfifo, ESP_CMDFIFO_SZ);
1557 }
1558 
1559 static void esp_class_init(ObjectClass *klass, void *data)
1560 {
1561     DeviceClass *dc = DEVICE_CLASS(klass);
1562 
1563     /* internal device for sysbusesp/pciespscsi, not user-creatable */
1564     dc->user_creatable = false;
1565     set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
1566 }
1567 
1568 static const TypeInfo esp_info = {
1569     .name = TYPE_ESP,
1570     .parent = TYPE_DEVICE,
1571     .instance_init = esp_init,
1572     .instance_finalize = esp_finalize,
1573     .instance_size = sizeof(ESPState),
1574     .class_init = esp_class_init,
1575 };
1576 
1577 static void esp_register_types(void)
1578 {
1579     type_register_static(&sysbus_esp_info);
1580     type_register_static(&esp_info);
1581 }
1582 
1583 type_init(esp_register_types)
1584