xref: /qemu/hw/scsi/esp.c (revision cb9881999dead51723bc5eb6d6fc2837f9345920)
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_done(ESPState *s)
547 {
548     s->rregs[ESP_RINTR] |= INTR_BS;
549     esp_raise_irq(s);
550 }
551 
552 static void do_dma_pdma_cb(ESPState *s)
553 {
554     int to_device = ((s->rregs[ESP_RSTAT] & 7) == STAT_DO);
555     uint8_t buf[ESP_CMDFIFO_SZ];
556     int len;
557     uint32_t n;
558 
559     if (s->do_cmd) {
560         /* Copy FIFO into cmdfifo */
561         n = esp_fifo_pop_buf(&s->fifo, buf, fifo8_num_used(&s->fifo));
562         n = MIN(fifo8_num_free(&s->cmdfifo), n);
563         fifo8_push_all(&s->cmdfifo, buf, n);
564 
565         /* Ensure we have received complete command after SATN and stop */
566         if (esp_get_tc(s) || fifo8_is_empty(&s->cmdfifo)) {
567             return;
568         }
569 
570         s->ti_size = 0;
571         if ((s->rregs[ESP_RSTAT] & 7) == STAT_CD) {
572             /* No command received */
573             if (s->cmdfifo_cdb_offset == fifo8_num_used(&s->cmdfifo)) {
574                 return;
575             }
576 
577             /* Command has been received */
578             s->do_cmd = 0;
579             do_cmd(s);
580         } else {
581             /*
582              * Extra message out bytes received: update cmdfifo_cdb_offset
583              * and then switch to command phase
584              */
585             s->cmdfifo_cdb_offset = fifo8_num_used(&s->cmdfifo);
586             esp_set_phase(s, STAT_CD);
587             s->rregs[ESP_RSEQ] = SEQ_CD;
588             s->rregs[ESP_RINTR] |= INTR_BS;
589             esp_raise_irq(s);
590         }
591         return;
592     }
593 
594     if (!s->current_req) {
595         return;
596     }
597 
598     if (to_device) {
599         /* Copy FIFO data to device */
600         len = MIN(s->async_len, ESP_FIFO_SZ);
601         len = MIN(len, fifo8_num_used(&s->fifo));
602         n = esp_fifo_pop_buf(&s->fifo, s->async_buf, len);
603         s->async_buf += n;
604         s->async_len -= n;
605         s->ti_size += n;
606 
607         if (s->async_len == 0 && fifo8_num_used(&s->fifo) < 2) {
608             /* Defer until the scsi layer has completed */
609             scsi_req_continue(s->current_req);
610             return;
611         }
612 
613         if (esp_get_tc(s) == 0 && fifo8_num_used(&s->fifo) < 2) {
614             esp_lower_drq(s);
615             esp_dma_done(s);
616         }
617 
618         return;
619     } else {
620         if (s->async_len == 0 && fifo8_num_used(&s->fifo) < 2) {
621             /* Defer until the scsi layer has completed */
622             scsi_req_continue(s->current_req);
623             s->data_in_ready = false;
624             return;
625         }
626 
627         if (esp_get_tc(s) == 0 && fifo8_num_used(&s->fifo) < 2) {
628             esp_lower_drq(s);
629             esp_dma_done(s);
630         }
631 
632         /* Copy device data to FIFO */
633         len = MIN(s->async_len, esp_get_tc(s));
634         len = MIN(len, fifo8_num_free(&s->fifo));
635         fifo8_push_all(&s->fifo, s->async_buf, len);
636         s->async_buf += len;
637         s->async_len -= len;
638         s->ti_size -= len;
639         esp_set_tc(s, esp_get_tc(s) - len);
640     }
641 }
642 
643 static void esp_do_dma(ESPState *s)
644 {
645     uint32_t len, cmdlen;
646     int to_device = ((s->rregs[ESP_RSTAT] & 7) == STAT_DO);
647     uint8_t buf[ESP_CMDFIFO_SZ];
648 
649     len = esp_get_tc(s);
650     if (s->do_cmd) {
651         /*
652          * handle_ti_cmd() case: esp_do_dma() is called only from
653          * handle_ti_cmd() with do_cmd != NULL (see the assert())
654          */
655         cmdlen = fifo8_num_used(&s->cmdfifo);
656         trace_esp_do_dma(cmdlen, len);
657         if (s->dma_memory_read) {
658             len = MIN(len, fifo8_num_free(&s->cmdfifo));
659             s->dma_memory_read(s->dma_opaque, buf, len);
660             fifo8_push_all(&s->cmdfifo, buf, len);
661             esp_set_tc(s, esp_get_tc(s) - len);
662         } else {
663             esp_set_pdma_cb(s, DO_DMA_PDMA_CB);
664             esp_raise_drq(s);
665             return;
666         }
667         trace_esp_handle_ti_cmd(cmdlen);
668         s->ti_size = 0;
669         if ((s->rregs[ESP_RSTAT] & 7) == STAT_CD) {
670             /* No command received */
671             if (s->cmdfifo_cdb_offset == fifo8_num_used(&s->cmdfifo)) {
672                 return;
673             }
674 
675             /* Command has been received */
676             s->do_cmd = 0;
677             do_cmd(s);
678         } else {
679             /*
680              * Extra message out bytes received: update cmdfifo_cdb_offset
681              * and then switch to command phase
682              */
683             s->cmdfifo_cdb_offset = fifo8_num_used(&s->cmdfifo);
684             esp_set_phase(s, STAT_CD);
685             s->rregs[ESP_RSEQ] = SEQ_CD;
686             s->rregs[ESP_RINTR] |= INTR_BS;
687             esp_raise_irq(s);
688         }
689         return;
690     }
691     if (!s->current_req) {
692         return;
693     }
694     if (s->async_len == 0) {
695         /* Defer until data is available.  */
696         return;
697     }
698     if (len > s->async_len) {
699         len = s->async_len;
700     }
701     if (to_device) {
702         if (s->dma_memory_read) {
703             s->dma_memory_read(s->dma_opaque, s->async_buf, len);
704 
705             esp_set_tc(s, esp_get_tc(s) - len);
706             s->async_buf += len;
707             s->async_len -= len;
708             s->ti_size += len;
709 
710             if (s->async_len == 0 && fifo8_num_used(&s->fifo) < 2) {
711                 /* Defer until the scsi layer has completed */
712                 scsi_req_continue(s->current_req);
713                 return;
714             }
715 
716             if (esp_get_tc(s) == 0 && fifo8_num_used(&s->fifo) < 2) {
717                 esp_dma_done(s);
718                 esp_lower_drq(s);
719             }
720         } else {
721             esp_set_pdma_cb(s, DO_DMA_PDMA_CB);
722             esp_raise_drq(s);
723 
724             if (s->async_len == 0 && fifo8_num_used(&s->fifo) < 2) {
725                 /* Defer until the scsi layer has completed */
726                 scsi_req_continue(s->current_req);
727                 return;
728             }
729 
730             if (esp_get_tc(s) == 0 && fifo8_num_used(&s->fifo) < 2) {
731                 esp_dma_done(s);
732                 esp_lower_drq(s);
733             }
734         }
735     } else {
736         if (s->dma_memory_write) {
737             s->dma_memory_write(s->dma_opaque, s->async_buf, len);
738 
739             esp_set_tc(s, esp_get_tc(s) - len);
740             s->async_buf += len;
741             s->async_len -= len;
742             s->ti_size -= len;
743 
744             if (s->async_len == 0 && fifo8_num_used(&s->fifo) < 2) {
745                 /* Defer until the scsi layer has completed */
746                 scsi_req_continue(s->current_req);
747                 return;
748             }
749 
750             if (esp_get_tc(s) == 0 && fifo8_num_used(&s->fifo) < 2) {
751                 esp_dma_done(s);
752                 esp_lower_drq(s);
753             }
754         } else {
755             /* Copy device data to FIFO */
756             len = MIN(len, fifo8_num_free(&s->fifo));
757             fifo8_push_all(&s->fifo, s->async_buf, len);
758             s->async_buf += len;
759             s->async_len -= len;
760             s->ti_size -= len;
761             esp_set_tc(s, esp_get_tc(s) - len);
762             esp_set_pdma_cb(s, DO_DMA_PDMA_CB);
763             esp_raise_drq(s);
764 
765             if (s->async_len == 0 && fifo8_num_used(&s->fifo) < 2) {
766                 /* Defer until the scsi layer has completed */
767                 scsi_req_continue(s->current_req);
768                 return;
769             }
770 
771             if (esp_get_tc(s) == 0 && fifo8_num_used(&s->fifo) < 2) {
772                 esp_lower_drq(s);
773                 esp_dma_done(s);
774             }
775         }
776     }
777 }
778 
779 static void esp_do_nodma(ESPState *s)
780 {
781     int to_device = ((s->rregs[ESP_RSTAT] & 7) == STAT_DO);
782     uint8_t buf[ESP_FIFO_SZ];
783     uint32_t cmdlen;
784     int len, n;
785 
786     if (s->do_cmd) {
787         /* Copy FIFO into cmdfifo */
788         n = esp_fifo_pop_buf(&s->fifo, buf, fifo8_num_used(&s->fifo));
789         n = MIN(fifo8_num_free(&s->cmdfifo), n);
790         fifo8_push_all(&s->cmdfifo, buf, n);
791 
792         cmdlen = fifo8_num_used(&s->cmdfifo);
793         trace_esp_handle_ti_cmd(cmdlen);
794         s->ti_size = 0;
795         if ((s->rregs[ESP_RSTAT] & 7) == STAT_CD) {
796             /* No command received */
797             if (s->cmdfifo_cdb_offset == fifo8_num_used(&s->cmdfifo)) {
798                 return;
799             }
800 
801             /* Command has been received */
802             s->do_cmd = 0;
803             do_cmd(s);
804         } else {
805             /*
806              * Extra message out bytes received: update cmdfifo_cdb_offset
807              * and then switch to command phase
808              */
809             s->cmdfifo_cdb_offset = fifo8_num_used(&s->cmdfifo);
810             esp_set_phase(s, STAT_CD);
811             s->rregs[ESP_RSEQ] = SEQ_CD;
812             s->rregs[ESP_RINTR] |= INTR_BS;
813             esp_raise_irq(s);
814         }
815         return;
816     }
817 
818     if (!s->current_req) {
819         return;
820     }
821 
822     if (s->async_len == 0) {
823         /* Defer until data is available.  */
824         return;
825     }
826 
827     if (to_device) {
828         len = MIN(s->async_len, ESP_FIFO_SZ);
829         len = MIN(len, fifo8_num_used(&s->fifo));
830         esp_fifo_pop_buf(&s->fifo, s->async_buf, len);
831         s->async_buf += len;
832         s->async_len -= len;
833         s->ti_size += len;
834     } else {
835         if (fifo8_is_empty(&s->fifo)) {
836             fifo8_push(&s->fifo, s->async_buf[0]);
837             s->async_buf++;
838             s->async_len--;
839             s->ti_size--;
840         }
841     }
842 
843     if (s->async_len == 0) {
844         scsi_req_continue(s->current_req);
845         return;
846     }
847 
848     s->rregs[ESP_RINTR] |= INTR_BS;
849     esp_raise_irq(s);
850 }
851 
852 static void esp_pdma_cb(ESPState *s)
853 {
854     switch (s->pdma_cb) {
855     case SATN_PDMA_CB:
856         satn_pdma_cb(s);
857         break;
858     case S_WITHOUT_SATN_PDMA_CB:
859         s_without_satn_pdma_cb(s);
860         break;
861     case SATN_STOP_PDMA_CB:
862         satn_stop_pdma_cb(s);
863         break;
864     case WRITE_RESPONSE_PDMA_CB:
865         write_response_pdma_cb(s);
866         break;
867     case DO_DMA_PDMA_CB:
868         do_dma_pdma_cb(s);
869         break;
870     default:
871         g_assert_not_reached();
872     }
873 }
874 
875 void esp_command_complete(SCSIRequest *req, size_t resid)
876 {
877     ESPState *s = req->hba_private;
878     int to_device = ((s->rregs[ESP_RSTAT] & 7) == STAT_DO);
879 
880     trace_esp_command_complete();
881 
882     /*
883      * Non-DMA transfers from the target will leave the last byte in
884      * the FIFO so don't reset ti_size in this case
885      */
886     if (s->dma || to_device) {
887         if (s->ti_size != 0) {
888             trace_esp_command_complete_unexpected();
889         }
890     }
891 
892     s->async_len = 0;
893     if (req->status) {
894         trace_esp_command_complete_fail();
895     }
896     s->status = req->status;
897 
898     /*
899      * Switch to status phase. For non-DMA transfers from the target the last
900      * byte is still in the FIFO
901      */
902     esp_set_phase(s, STAT_ST);
903     if (s->ti_size == 0) {
904         /*
905          * Transfer complete: force TC to zero just in case a TI command was
906          * requested for more data than the command returns (Solaris 8 does
907          * this)
908          */
909         esp_set_tc(s, 0);
910         esp_dma_done(s);
911     } else {
912         /*
913          * Transfer truncated: raise INTR_BS to indicate early change of
914          * phase
915          */
916         s->rregs[ESP_RINTR] |= INTR_BS;
917         esp_raise_irq(s);
918         s->ti_size = 0;
919     }
920 
921     if (s->current_req) {
922         scsi_req_unref(s->current_req);
923         s->current_req = NULL;
924         s->current_dev = NULL;
925     }
926 }
927 
928 void esp_transfer_data(SCSIRequest *req, uint32_t len)
929 {
930     ESPState *s = req->hba_private;
931     int to_device = ((s->rregs[ESP_RSTAT] & 7) == STAT_DO);
932     uint32_t dmalen = esp_get_tc(s);
933 
934     assert(!s->do_cmd);
935     trace_esp_transfer_data(dmalen, s->ti_size);
936     s->async_len = len;
937     s->async_buf = scsi_req_get_buf(req);
938 
939     if (!to_device && !s->data_in_ready) {
940         /*
941          * Initial incoming data xfer is complete so raise command
942          * completion interrupt
943          */
944         s->data_in_ready = true;
945         s->rregs[ESP_RINTR] |= INTR_BS;
946         esp_raise_irq(s);
947     }
948 
949     /*
950      * Always perform the initial transfer upon reception of the next TI
951      * command to ensure the DMA/non-DMA status of the command is correct.
952      * It is not possible to use s->dma directly in the section below as
953      * some OSs send non-DMA NOP commands after a DMA transfer. Hence if the
954      * async data transfer is delayed then s->dma is set incorrectly.
955      */
956 
957     if (s->ti_cmd == (CMD_TI | CMD_DMA)) {
958         /* When the SCSI layer returns more data, raise deferred INTR_BS */
959         esp_dma_done(s);
960 
961         esp_do_dma(s);
962     } else if (s->ti_cmd == CMD_TI) {
963         esp_do_nodma(s);
964     }
965 }
966 
967 static void handle_ti(ESPState *s)
968 {
969     uint32_t dmalen;
970 
971     if (s->dma && !s->dma_enabled) {
972         s->dma_cb = handle_ti;
973         return;
974     }
975 
976     s->ti_cmd = s->rregs[ESP_CMD];
977     if (s->dma) {
978         dmalen = esp_get_tc(s);
979         trace_esp_handle_ti(dmalen);
980         esp_do_dma(s);
981     } else {
982         trace_esp_handle_ti(s->ti_size);
983         esp_do_nodma(s);
984     }
985 }
986 
987 void esp_hard_reset(ESPState *s)
988 {
989     memset(s->rregs, 0, ESP_REGS);
990     memset(s->wregs, 0, ESP_REGS);
991     s->tchi_written = 0;
992     s->ti_size = 0;
993     s->async_len = 0;
994     fifo8_reset(&s->fifo);
995     fifo8_reset(&s->cmdfifo);
996     s->dma = 0;
997     s->do_cmd = 0;
998     s->dma_cb = NULL;
999 
1000     s->rregs[ESP_CFG1] = 7;
1001 }
1002 
1003 static void esp_soft_reset(ESPState *s)
1004 {
1005     qemu_irq_lower(s->irq);
1006     qemu_irq_lower(s->irq_data);
1007     esp_hard_reset(s);
1008 }
1009 
1010 static void esp_bus_reset(ESPState *s)
1011 {
1012     bus_cold_reset(BUS(&s->bus));
1013 }
1014 
1015 static void parent_esp_reset(ESPState *s, int irq, int level)
1016 {
1017     if (level) {
1018         esp_soft_reset(s);
1019     }
1020 }
1021 
1022 static void esp_run_cmd(ESPState *s)
1023 {
1024     uint8_t cmd = s->rregs[ESP_CMD];
1025 
1026     if (cmd & CMD_DMA) {
1027         s->dma = 1;
1028         /* Reload DMA counter.  */
1029         if (esp_get_stc(s) == 0) {
1030             esp_set_tc(s, 0x10000);
1031         } else {
1032             esp_set_tc(s, esp_get_stc(s));
1033         }
1034     } else {
1035         s->dma = 0;
1036     }
1037     switch (cmd & CMD_CMD) {
1038     case CMD_NOP:
1039         trace_esp_mem_writeb_cmd_nop(cmd);
1040         break;
1041     case CMD_FLUSH:
1042         trace_esp_mem_writeb_cmd_flush(cmd);
1043         fifo8_reset(&s->fifo);
1044         break;
1045     case CMD_RESET:
1046         trace_esp_mem_writeb_cmd_reset(cmd);
1047         esp_soft_reset(s);
1048         break;
1049     case CMD_BUSRESET:
1050         trace_esp_mem_writeb_cmd_bus_reset(cmd);
1051         esp_bus_reset(s);
1052         if (!(s->wregs[ESP_CFG1] & CFG1_RESREPT)) {
1053             s->rregs[ESP_RINTR] |= INTR_RST;
1054             esp_raise_irq(s);
1055         }
1056         break;
1057     case CMD_TI:
1058         trace_esp_mem_writeb_cmd_ti(cmd);
1059         handle_ti(s);
1060         break;
1061     case CMD_ICCS:
1062         trace_esp_mem_writeb_cmd_iccs(cmd);
1063         write_response(s);
1064         s->rregs[ESP_RINTR] |= INTR_FC;
1065         esp_set_phase(s, STAT_MI);
1066         break;
1067     case CMD_MSGACC:
1068         trace_esp_mem_writeb_cmd_msgacc(cmd);
1069         s->rregs[ESP_RINTR] |= INTR_DC;
1070         s->rregs[ESP_RSEQ] = 0;
1071         s->rregs[ESP_RFLAGS] = 0;
1072         esp_raise_irq(s);
1073         break;
1074     case CMD_PAD:
1075         trace_esp_mem_writeb_cmd_pad(cmd);
1076         s->rregs[ESP_RSTAT] = STAT_TC;
1077         s->rregs[ESP_RINTR] |= INTR_FC;
1078         s->rregs[ESP_RSEQ] = 0;
1079         break;
1080     case CMD_SATN:
1081         trace_esp_mem_writeb_cmd_satn(cmd);
1082         break;
1083     case CMD_RSTATN:
1084         trace_esp_mem_writeb_cmd_rstatn(cmd);
1085         break;
1086     case CMD_SEL:
1087         trace_esp_mem_writeb_cmd_sel(cmd);
1088         handle_s_without_atn(s);
1089         break;
1090     case CMD_SELATN:
1091         trace_esp_mem_writeb_cmd_selatn(cmd);
1092         handle_satn(s);
1093         break;
1094     case CMD_SELATNS:
1095         trace_esp_mem_writeb_cmd_selatns(cmd);
1096         handle_satn_stop(s);
1097         break;
1098     case CMD_ENSEL:
1099         trace_esp_mem_writeb_cmd_ensel(cmd);
1100         s->rregs[ESP_RINTR] = 0;
1101         break;
1102     case CMD_DISSEL:
1103         trace_esp_mem_writeb_cmd_dissel(cmd);
1104         s->rregs[ESP_RINTR] = 0;
1105         esp_raise_irq(s);
1106         break;
1107     default:
1108         trace_esp_error_unhandled_command(cmd);
1109         break;
1110     }
1111 }
1112 
1113 uint64_t esp_reg_read(ESPState *s, uint32_t saddr)
1114 {
1115     uint32_t val;
1116 
1117     switch (saddr) {
1118     case ESP_FIFO:
1119         if (s->dma_memory_read && s->dma_memory_write &&
1120                 (s->rregs[ESP_RSTAT] & STAT_PIO_MASK) == 0) {
1121             /* Data out.  */
1122             qemu_log_mask(LOG_UNIMP, "esp: PIO data read not implemented\n");
1123             s->rregs[ESP_FIFO] = 0;
1124         } else {
1125             if ((s->rregs[ESP_RSTAT] & 0x7) == STAT_DI) {
1126                 if (s->ti_size) {
1127                     esp_do_nodma(s);
1128                 } else {
1129                     /*
1130                      * The last byte of a non-DMA transfer has been read out
1131                      * of the FIFO so switch to status phase
1132                      */
1133                     esp_set_phase(s, STAT_ST);
1134                 }
1135             }
1136             s->rregs[ESP_FIFO] = esp_fifo_pop(&s->fifo);
1137         }
1138         val = s->rregs[ESP_FIFO];
1139         break;
1140     case ESP_RINTR:
1141         /*
1142          * Clear sequence step, interrupt register and all status bits
1143          * except TC
1144          */
1145         val = s->rregs[ESP_RINTR];
1146         s->rregs[ESP_RINTR] = 0;
1147         s->rregs[ESP_RSTAT] &= ~STAT_TC;
1148         /*
1149          * According to the datasheet ESP_RSEQ should be cleared, but as the
1150          * emulation currently defers information transfers to the next TI
1151          * command leave it for now so that pedantic guests such as the old
1152          * Linux 2.6 driver see the correct flags before the next SCSI phase
1153          * transition.
1154          *
1155          * s->rregs[ESP_RSEQ] = SEQ_0;
1156          */
1157         esp_lower_irq(s);
1158         break;
1159     case ESP_TCHI:
1160         /* Return the unique id if the value has never been written */
1161         if (!s->tchi_written) {
1162             val = s->chip_id;
1163         } else {
1164             val = s->rregs[saddr];
1165         }
1166         break;
1167      case ESP_RFLAGS:
1168         /* Bottom 5 bits indicate number of bytes in FIFO */
1169         val = fifo8_num_used(&s->fifo);
1170         break;
1171     default:
1172         val = s->rregs[saddr];
1173         break;
1174     }
1175 
1176     trace_esp_mem_readb(saddr, val);
1177     return val;
1178 }
1179 
1180 void esp_reg_write(ESPState *s, uint32_t saddr, uint64_t val)
1181 {
1182     trace_esp_mem_writeb(saddr, s->wregs[saddr], val);
1183     switch (saddr) {
1184     case ESP_TCHI:
1185         s->tchi_written = true;
1186         /* fall through */
1187     case ESP_TCLO:
1188     case ESP_TCMID:
1189         s->rregs[ESP_RSTAT] &= ~STAT_TC;
1190         break;
1191     case ESP_FIFO:
1192         if (s->do_cmd) {
1193             if (!fifo8_is_full(&s->fifo)) {
1194                 esp_fifo_push(&s->fifo, val);
1195                 esp_fifo_push(&s->cmdfifo, fifo8_pop(&s->fifo));
1196             }
1197 
1198             /*
1199              * If any unexpected message out/command phase data is
1200              * transferred using non-DMA, raise the interrupt
1201              */
1202             if (s->rregs[ESP_CMD] == CMD_TI) {
1203                 s->rregs[ESP_RINTR] |= INTR_BS;
1204                 esp_raise_irq(s);
1205             }
1206         } else {
1207             esp_fifo_push(&s->fifo, val);
1208         }
1209         break;
1210     case ESP_CMD:
1211         s->rregs[saddr] = val;
1212         esp_run_cmd(s);
1213         break;
1214     case ESP_WBUSID ... ESP_WSYNO:
1215         break;
1216     case ESP_CFG1:
1217     case ESP_CFG2: case ESP_CFG3:
1218     case ESP_RES3: case ESP_RES4:
1219         s->rregs[saddr] = val;
1220         break;
1221     case ESP_WCCF ... ESP_WTEST:
1222         break;
1223     default:
1224         trace_esp_error_invalid_write(val, saddr);
1225         return;
1226     }
1227     s->wregs[saddr] = val;
1228 }
1229 
1230 static bool esp_mem_accepts(void *opaque, hwaddr addr,
1231                             unsigned size, bool is_write,
1232                             MemTxAttrs attrs)
1233 {
1234     return (size == 1) || (is_write && size == 4);
1235 }
1236 
1237 static bool esp_is_before_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_5(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 >= 5;
1251 }
1252 
1253 static bool esp_is_version_6(void *opaque, int version_id)
1254 {
1255     ESPState *s = ESP(opaque);
1256 
1257     version_id = MIN(version_id, s->mig_version_id);
1258     return version_id >= 6;
1259 }
1260 
1261 int esp_pre_save(void *opaque)
1262 {
1263     ESPState *s = ESP(object_resolve_path_component(
1264                       OBJECT(opaque), "esp"));
1265 
1266     s->mig_version_id = vmstate_esp.version_id;
1267     return 0;
1268 }
1269 
1270 static int esp_post_load(void *opaque, int version_id)
1271 {
1272     ESPState *s = ESP(opaque);
1273     int len, i;
1274 
1275     version_id = MIN(version_id, s->mig_version_id);
1276 
1277     if (version_id < 5) {
1278         esp_set_tc(s, s->mig_dma_left);
1279 
1280         /* Migrate ti_buf to fifo */
1281         len = s->mig_ti_wptr - s->mig_ti_rptr;
1282         for (i = 0; i < len; i++) {
1283             fifo8_push(&s->fifo, s->mig_ti_buf[i]);
1284         }
1285 
1286         /* Migrate cmdbuf to cmdfifo */
1287         for (i = 0; i < s->mig_cmdlen; i++) {
1288             fifo8_push(&s->cmdfifo, s->mig_cmdbuf[i]);
1289         }
1290     }
1291 
1292     s->mig_version_id = vmstate_esp.version_id;
1293     return 0;
1294 }
1295 
1296 /*
1297  * PDMA (or pseudo-DMA) is only used on the Macintosh and requires the
1298  * guest CPU to perform the transfers between the SCSI bus and memory
1299  * itself. This is indicated by the dma_memory_read and dma_memory_write
1300  * functions being NULL (in contrast to the ESP PCI device) whilst
1301  * dma_enabled is still set.
1302  */
1303 
1304 static bool esp_pdma_needed(void *opaque)
1305 {
1306     ESPState *s = ESP(opaque);
1307 
1308     return s->dma_memory_read == NULL && s->dma_memory_write == NULL &&
1309            s->dma_enabled;
1310 }
1311 
1312 static const VMStateDescription vmstate_esp_pdma = {
1313     .name = "esp/pdma",
1314     .version_id = 0,
1315     .minimum_version_id = 0,
1316     .needed = esp_pdma_needed,
1317     .fields = (const VMStateField[]) {
1318         VMSTATE_UINT8(pdma_cb, ESPState),
1319         VMSTATE_END_OF_LIST()
1320     }
1321 };
1322 
1323 const VMStateDescription vmstate_esp = {
1324     .name = "esp",
1325     .version_id = 6,
1326     .minimum_version_id = 3,
1327     .post_load = esp_post_load,
1328     .fields = (const VMStateField[]) {
1329         VMSTATE_BUFFER(rregs, ESPState),
1330         VMSTATE_BUFFER(wregs, ESPState),
1331         VMSTATE_INT32(ti_size, ESPState),
1332         VMSTATE_UINT32_TEST(mig_ti_rptr, ESPState, esp_is_before_version_5),
1333         VMSTATE_UINT32_TEST(mig_ti_wptr, ESPState, esp_is_before_version_5),
1334         VMSTATE_BUFFER_TEST(mig_ti_buf, ESPState, esp_is_before_version_5),
1335         VMSTATE_UINT32(status, ESPState),
1336         VMSTATE_UINT32_TEST(mig_deferred_status, ESPState,
1337                             esp_is_before_version_5),
1338         VMSTATE_BOOL_TEST(mig_deferred_complete, ESPState,
1339                           esp_is_before_version_5),
1340         VMSTATE_UINT32(dma, ESPState),
1341         VMSTATE_STATIC_BUFFER(mig_cmdbuf, ESPState, 0,
1342                               esp_is_before_version_5, 0, 16),
1343         VMSTATE_STATIC_BUFFER(mig_cmdbuf, ESPState, 4,
1344                               esp_is_before_version_5, 16,
1345                               sizeof(typeof_field(ESPState, mig_cmdbuf))),
1346         VMSTATE_UINT32_TEST(mig_cmdlen, ESPState, esp_is_before_version_5),
1347         VMSTATE_UINT32(do_cmd, ESPState),
1348         VMSTATE_UINT32_TEST(mig_dma_left, ESPState, esp_is_before_version_5),
1349         VMSTATE_BOOL_TEST(data_in_ready, ESPState, esp_is_version_5),
1350         VMSTATE_UINT8_TEST(cmdfifo_cdb_offset, ESPState, esp_is_version_5),
1351         VMSTATE_FIFO8_TEST(fifo, ESPState, esp_is_version_5),
1352         VMSTATE_FIFO8_TEST(cmdfifo, ESPState, esp_is_version_5),
1353         VMSTATE_UINT8_TEST(ti_cmd, ESPState, esp_is_version_5),
1354         VMSTATE_UINT8_TEST(lun, ESPState, esp_is_version_6),
1355         VMSTATE_END_OF_LIST()
1356     },
1357     .subsections = (const VMStateDescription * const []) {
1358         &vmstate_esp_pdma,
1359         NULL
1360     }
1361 };
1362 
1363 static void sysbus_esp_mem_write(void *opaque, hwaddr addr,
1364                                  uint64_t val, unsigned int size)
1365 {
1366     SysBusESPState *sysbus = opaque;
1367     ESPState *s = ESP(&sysbus->esp);
1368     uint32_t saddr;
1369 
1370     saddr = addr >> sysbus->it_shift;
1371     esp_reg_write(s, saddr, val);
1372 }
1373 
1374 static uint64_t sysbus_esp_mem_read(void *opaque, hwaddr addr,
1375                                     unsigned int size)
1376 {
1377     SysBusESPState *sysbus = opaque;
1378     ESPState *s = ESP(&sysbus->esp);
1379     uint32_t saddr;
1380 
1381     saddr = addr >> sysbus->it_shift;
1382     return esp_reg_read(s, saddr);
1383 }
1384 
1385 static const MemoryRegionOps sysbus_esp_mem_ops = {
1386     .read = sysbus_esp_mem_read,
1387     .write = sysbus_esp_mem_write,
1388     .endianness = DEVICE_NATIVE_ENDIAN,
1389     .valid.accepts = esp_mem_accepts,
1390 };
1391 
1392 static void sysbus_esp_pdma_write(void *opaque, hwaddr addr,
1393                                   uint64_t val, unsigned int size)
1394 {
1395     SysBusESPState *sysbus = opaque;
1396     ESPState *s = ESP(&sysbus->esp);
1397 
1398     trace_esp_pdma_write(size);
1399 
1400     switch (size) {
1401     case 1:
1402         esp_pdma_write(s, val);
1403         break;
1404     case 2:
1405         esp_pdma_write(s, val >> 8);
1406         esp_pdma_write(s, val);
1407         break;
1408     }
1409     esp_pdma_cb(s);
1410 }
1411 
1412 static uint64_t sysbus_esp_pdma_read(void *opaque, hwaddr addr,
1413                                      unsigned int size)
1414 {
1415     SysBusESPState *sysbus = opaque;
1416     ESPState *s = ESP(&sysbus->esp);
1417     uint64_t val = 0;
1418 
1419     trace_esp_pdma_read(size);
1420 
1421     switch (size) {
1422     case 1:
1423         val = esp_pdma_read(s);
1424         break;
1425     case 2:
1426         val = esp_pdma_read(s);
1427         val = (val << 8) | esp_pdma_read(s);
1428         break;
1429     }
1430     esp_pdma_cb(s);
1431     return val;
1432 }
1433 
1434 static void *esp_load_request(QEMUFile *f, SCSIRequest *req)
1435 {
1436     ESPState *s = container_of(req->bus, ESPState, bus);
1437 
1438     scsi_req_ref(req);
1439     s->current_req = req;
1440     return s;
1441 }
1442 
1443 static const MemoryRegionOps sysbus_esp_pdma_ops = {
1444     .read = sysbus_esp_pdma_read,
1445     .write = sysbus_esp_pdma_write,
1446     .endianness = DEVICE_NATIVE_ENDIAN,
1447     .valid.min_access_size = 1,
1448     .valid.max_access_size = 4,
1449     .impl.min_access_size = 1,
1450     .impl.max_access_size = 2,
1451 };
1452 
1453 static const struct SCSIBusInfo esp_scsi_info = {
1454     .tcq = false,
1455     .max_target = ESP_MAX_DEVS,
1456     .max_lun = 7,
1457 
1458     .load_request = esp_load_request,
1459     .transfer_data = esp_transfer_data,
1460     .complete = esp_command_complete,
1461     .cancel = esp_request_cancelled
1462 };
1463 
1464 static void sysbus_esp_gpio_demux(void *opaque, int irq, int level)
1465 {
1466     SysBusESPState *sysbus = SYSBUS_ESP(opaque);
1467     ESPState *s = ESP(&sysbus->esp);
1468 
1469     switch (irq) {
1470     case 0:
1471         parent_esp_reset(s, irq, level);
1472         break;
1473     case 1:
1474         esp_dma_enable(s, irq, level);
1475         break;
1476     }
1477 }
1478 
1479 static void sysbus_esp_realize(DeviceState *dev, Error **errp)
1480 {
1481     SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
1482     SysBusESPState *sysbus = SYSBUS_ESP(dev);
1483     ESPState *s = ESP(&sysbus->esp);
1484 
1485     if (!qdev_realize(DEVICE(s), NULL, errp)) {
1486         return;
1487     }
1488 
1489     sysbus_init_irq(sbd, &s->irq);
1490     sysbus_init_irq(sbd, &s->irq_data);
1491     assert(sysbus->it_shift != -1);
1492 
1493     s->chip_id = TCHI_FAS100A;
1494     memory_region_init_io(&sysbus->iomem, OBJECT(sysbus), &sysbus_esp_mem_ops,
1495                           sysbus, "esp-regs", ESP_REGS << sysbus->it_shift);
1496     sysbus_init_mmio(sbd, &sysbus->iomem);
1497     memory_region_init_io(&sysbus->pdma, OBJECT(sysbus), &sysbus_esp_pdma_ops,
1498                           sysbus, "esp-pdma", 4);
1499     sysbus_init_mmio(sbd, &sysbus->pdma);
1500 
1501     qdev_init_gpio_in(dev, sysbus_esp_gpio_demux, 2);
1502 
1503     scsi_bus_init(&s->bus, sizeof(s->bus), dev, &esp_scsi_info);
1504 }
1505 
1506 static void sysbus_esp_hard_reset(DeviceState *dev)
1507 {
1508     SysBusESPState *sysbus = SYSBUS_ESP(dev);
1509     ESPState *s = ESP(&sysbus->esp);
1510 
1511     esp_hard_reset(s);
1512 }
1513 
1514 static void sysbus_esp_init(Object *obj)
1515 {
1516     SysBusESPState *sysbus = SYSBUS_ESP(obj);
1517 
1518     object_initialize_child(obj, "esp", &sysbus->esp, TYPE_ESP);
1519 }
1520 
1521 static const VMStateDescription vmstate_sysbus_esp_scsi = {
1522     .name = "sysbusespscsi",
1523     .version_id = 2,
1524     .minimum_version_id = 1,
1525     .pre_save = esp_pre_save,
1526     .fields = (const VMStateField[]) {
1527         VMSTATE_UINT8_V(esp.mig_version_id, SysBusESPState, 2),
1528         VMSTATE_STRUCT(esp, SysBusESPState, 0, vmstate_esp, ESPState),
1529         VMSTATE_END_OF_LIST()
1530     }
1531 };
1532 
1533 static void sysbus_esp_class_init(ObjectClass *klass, void *data)
1534 {
1535     DeviceClass *dc = DEVICE_CLASS(klass);
1536 
1537     dc->realize = sysbus_esp_realize;
1538     dc->reset = sysbus_esp_hard_reset;
1539     dc->vmsd = &vmstate_sysbus_esp_scsi;
1540     set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
1541 }
1542 
1543 static const TypeInfo sysbus_esp_info = {
1544     .name          = TYPE_SYSBUS_ESP,
1545     .parent        = TYPE_SYS_BUS_DEVICE,
1546     .instance_init = sysbus_esp_init,
1547     .instance_size = sizeof(SysBusESPState),
1548     .class_init    = sysbus_esp_class_init,
1549 };
1550 
1551 static void esp_finalize(Object *obj)
1552 {
1553     ESPState *s = ESP(obj);
1554 
1555     fifo8_destroy(&s->fifo);
1556     fifo8_destroy(&s->cmdfifo);
1557 }
1558 
1559 static void esp_init(Object *obj)
1560 {
1561     ESPState *s = ESP(obj);
1562 
1563     fifo8_create(&s->fifo, ESP_FIFO_SZ);
1564     fifo8_create(&s->cmdfifo, ESP_CMDFIFO_SZ);
1565 }
1566 
1567 static void esp_class_init(ObjectClass *klass, void *data)
1568 {
1569     DeviceClass *dc = DEVICE_CLASS(klass);
1570 
1571     /* internal device for sysbusesp/pciespscsi, not user-creatable */
1572     dc->user_creatable = false;
1573     set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
1574 }
1575 
1576 static const TypeInfo esp_info = {
1577     .name = TYPE_ESP,
1578     .parent = TYPE_DEVICE,
1579     .instance_init = esp_init,
1580     .instance_finalize = esp_finalize,
1581     .instance_size = sizeof(ESPState),
1582     .class_init = esp_class_init,
1583 };
1584 
1585 static void esp_register_types(void)
1586 {
1587     type_register_static(&sysbus_esp_info);
1588     type_register_static(&esp_info);
1589 }
1590 
1591 type_init(esp_register_types)
1592