xref: /openbmc/qemu/hw/scsi/esp.c (revision 95fc5ed4)
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;
125 
126     if (maxlen == 0) {
127         return 0;
128     }
129 
130     buf = fifo8_pop_buf(fifo, maxlen, &n);
131     if (dest) {
132         memcpy(dest, buf, n);
133     }
134 
135     return n;
136 }
137 
138 static uint32_t esp_get_tc(ESPState *s)
139 {
140     uint32_t dmalen;
141 
142     dmalen = s->rregs[ESP_TCLO];
143     dmalen |= s->rregs[ESP_TCMID] << 8;
144     dmalen |= s->rregs[ESP_TCHI] << 16;
145 
146     return dmalen;
147 }
148 
149 static void esp_set_tc(ESPState *s, uint32_t dmalen)
150 {
151     s->rregs[ESP_TCLO] = dmalen;
152     s->rregs[ESP_TCMID] = dmalen >> 8;
153     s->rregs[ESP_TCHI] = dmalen >> 16;
154 }
155 
156 static uint32_t esp_get_stc(ESPState *s)
157 {
158     uint32_t dmalen;
159 
160     dmalen = s->wregs[ESP_TCLO];
161     dmalen |= s->wregs[ESP_TCMID] << 8;
162     dmalen |= s->wregs[ESP_TCHI] << 16;
163 
164     return dmalen;
165 }
166 
167 static uint8_t esp_pdma_read(ESPState *s)
168 {
169     uint8_t val;
170 
171     if (s->do_cmd) {
172         val = esp_fifo_pop(&s->cmdfifo);
173     } else {
174         val = esp_fifo_pop(&s->fifo);
175     }
176 
177     return val;
178 }
179 
180 static void esp_pdma_write(ESPState *s, uint8_t val)
181 {
182     uint32_t dmalen = esp_get_tc(s);
183 
184     if (dmalen == 0) {
185         return;
186     }
187 
188     if (s->do_cmd) {
189         esp_fifo_push(&s->cmdfifo, val);
190     } else {
191         esp_fifo_push(&s->fifo, val);
192     }
193 
194     dmalen--;
195     esp_set_tc(s, dmalen);
196 }
197 
198 static void esp_set_pdma_cb(ESPState *s, enum pdma_cb cb)
199 {
200     s->pdma_cb = cb;
201 }
202 
203 static int esp_select(ESPState *s)
204 {
205     int target;
206 
207     target = s->wregs[ESP_WBUSID] & BUSID_DID;
208 
209     s->ti_size = 0;
210     fifo8_reset(&s->fifo);
211 
212     s->current_dev = scsi_device_find(&s->bus, 0, target, 0);
213     if (!s->current_dev) {
214         /* No such drive */
215         s->rregs[ESP_RSTAT] = 0;
216         s->rregs[ESP_RINTR] = INTR_DC;
217         s->rregs[ESP_RSEQ] = SEQ_0;
218         esp_raise_irq(s);
219         return -1;
220     }
221 
222     /*
223      * Note that we deliberately don't raise the IRQ here: this will be done
224      * either in do_command_phase() for DATA OUT transfers or by the deferred
225      * IRQ mechanism in esp_transfer_data() for DATA IN transfers
226      */
227     s->rregs[ESP_RINTR] |= INTR_FC;
228     s->rregs[ESP_RSEQ] = SEQ_CD;
229     return 0;
230 }
231 
232 static uint32_t get_cmd(ESPState *s, uint32_t maxlen)
233 {
234     uint8_t buf[ESP_CMDFIFO_SZ];
235     uint32_t dmalen, n;
236     int target;
237 
238     if (s->current_req) {
239         /* Started a new command before the old one finished.  Cancel it.  */
240         scsi_req_cancel(s->current_req);
241     }
242 
243     target = s->wregs[ESP_WBUSID] & BUSID_DID;
244     if (s->dma) {
245         dmalen = MIN(esp_get_tc(s), maxlen);
246         if (dmalen == 0) {
247             return 0;
248         }
249         if (s->dma_memory_read) {
250             s->dma_memory_read(s->dma_opaque, buf, dmalen);
251             dmalen = MIN(fifo8_num_free(&s->cmdfifo), dmalen);
252             fifo8_push_all(&s->cmdfifo, buf, dmalen);
253         } else {
254             if (esp_select(s) < 0) {
255                 fifo8_reset(&s->cmdfifo);
256                 return -1;
257             }
258             esp_raise_drq(s);
259             fifo8_reset(&s->cmdfifo);
260             return 0;
261         }
262     } else {
263         dmalen = MIN(fifo8_num_used(&s->fifo), maxlen);
264         if (dmalen == 0) {
265             return 0;
266         }
267         n = esp_fifo_pop_buf(&s->fifo, buf, dmalen);
268         n = MIN(fifo8_num_free(&s->cmdfifo), n);
269         fifo8_push_all(&s->cmdfifo, buf, n);
270     }
271     trace_esp_get_cmd(dmalen, target);
272 
273     if (esp_select(s) < 0) {
274         fifo8_reset(&s->cmdfifo);
275         return -1;
276     }
277     return dmalen;
278 }
279 
280 static void do_command_phase(ESPState *s)
281 {
282     uint32_t cmdlen;
283     int32_t datalen;
284     SCSIDevice *current_lun;
285     uint8_t buf[ESP_CMDFIFO_SZ];
286 
287     trace_esp_do_command_phase(s->lun);
288     cmdlen = fifo8_num_used(&s->cmdfifo);
289     if (!cmdlen || !s->current_dev) {
290         return;
291     }
292     esp_fifo_pop_buf(&s->cmdfifo, buf, cmdlen);
293 
294     current_lun = scsi_device_find(&s->bus, 0, s->current_dev->id, s->lun);
295     s->current_req = scsi_req_new(current_lun, 0, s->lun, buf, cmdlen, s);
296     datalen = scsi_req_enqueue(s->current_req);
297     s->ti_size = datalen;
298     fifo8_reset(&s->cmdfifo);
299     if (datalen != 0) {
300         s->rregs[ESP_RSTAT] = STAT_TC;
301         s->rregs[ESP_RSEQ] = SEQ_CD;
302         s->ti_cmd = 0;
303         esp_set_tc(s, 0);
304         if (datalen > 0) {
305             /*
306              * Switch to DATA IN phase but wait until initial data xfer is
307              * complete before raising the command completion interrupt
308              */
309             s->data_in_ready = false;
310             s->rregs[ESP_RSTAT] |= STAT_DI;
311         } else {
312             s->rregs[ESP_RSTAT] |= STAT_DO;
313             s->rregs[ESP_RINTR] |= INTR_BS | INTR_FC;
314             esp_raise_irq(s);
315             esp_lower_drq(s);
316         }
317         scsi_req_continue(s->current_req);
318         return;
319     }
320 }
321 
322 static void do_message_phase(ESPState *s)
323 {
324     if (s->cmdfifo_cdb_offset) {
325         uint8_t message = esp_fifo_pop(&s->cmdfifo);
326 
327         trace_esp_do_identify(message);
328         s->lun = message & 7;
329         s->cmdfifo_cdb_offset--;
330     }
331 
332     /* Ignore extended messages for now */
333     if (s->cmdfifo_cdb_offset) {
334         int len = MIN(s->cmdfifo_cdb_offset, fifo8_num_used(&s->cmdfifo));
335         esp_fifo_pop_buf(&s->cmdfifo, NULL, len);
336         s->cmdfifo_cdb_offset = 0;
337     }
338 }
339 
340 static void do_cmd(ESPState *s)
341 {
342     do_message_phase(s);
343     assert(s->cmdfifo_cdb_offset == 0);
344     do_command_phase(s);
345 }
346 
347 static void satn_pdma_cb(ESPState *s)
348 {
349     if (!esp_get_tc(s) && !fifo8_is_empty(&s->cmdfifo)) {
350         s->cmdfifo_cdb_offset = 1;
351         s->do_cmd = 0;
352         do_cmd(s);
353     }
354 }
355 
356 static void handle_satn(ESPState *s)
357 {
358     int32_t cmdlen;
359 
360     if (s->dma && !s->dma_enabled) {
361         s->dma_cb = handle_satn;
362         return;
363     }
364     esp_set_pdma_cb(s, SATN_PDMA_CB);
365     cmdlen = get_cmd(s, ESP_CMDFIFO_SZ);
366     if (cmdlen > 0) {
367         s->cmdfifo_cdb_offset = 1;
368         s->do_cmd = 0;
369         do_cmd(s);
370     } else if (cmdlen == 0) {
371         s->do_cmd = 1;
372         /* Target present, but no cmd yet - switch to command phase */
373         s->rregs[ESP_RSEQ] = SEQ_CD;
374         s->rregs[ESP_RSTAT] = STAT_CD;
375     }
376 }
377 
378 static void s_without_satn_pdma_cb(ESPState *s)
379 {
380     if (!esp_get_tc(s) && !fifo8_is_empty(&s->cmdfifo)) {
381         s->cmdfifo_cdb_offset = 0;
382         s->do_cmd = 0;
383         do_cmd(s);
384     }
385 }
386 
387 static void handle_s_without_atn(ESPState *s)
388 {
389     int32_t cmdlen;
390 
391     if (s->dma && !s->dma_enabled) {
392         s->dma_cb = handle_s_without_atn;
393         return;
394     }
395     esp_set_pdma_cb(s, S_WITHOUT_SATN_PDMA_CB);
396     cmdlen = get_cmd(s, ESP_CMDFIFO_SZ);
397     if (cmdlen > 0) {
398         s->cmdfifo_cdb_offset = 0;
399         s->do_cmd = 0;
400         do_cmd(s);
401     } else if (cmdlen == 0) {
402         s->do_cmd = 1;
403         /* Target present, but no cmd yet - switch to command phase */
404         s->rregs[ESP_RSEQ] = SEQ_CD;
405         s->rregs[ESP_RSTAT] = STAT_CD;
406     }
407 }
408 
409 static void satn_stop_pdma_cb(ESPState *s)
410 {
411     if (!esp_get_tc(s) && !fifo8_is_empty(&s->cmdfifo)) {
412         trace_esp_handle_satn_stop(fifo8_num_used(&s->cmdfifo));
413         s->do_cmd = 1;
414         s->cmdfifo_cdb_offset = 1;
415         s->rregs[ESP_RSTAT] = STAT_TC | STAT_CD;
416         s->rregs[ESP_RINTR] |= INTR_BS | INTR_FC;
417         s->rregs[ESP_RSEQ] = SEQ_CD;
418         esp_raise_irq(s);
419     }
420 }
421 
422 static void handle_satn_stop(ESPState *s)
423 {
424     int32_t cmdlen;
425 
426     if (s->dma && !s->dma_enabled) {
427         s->dma_cb = handle_satn_stop;
428         return;
429     }
430     esp_set_pdma_cb(s, SATN_STOP_PDMA_CB);
431     cmdlen = get_cmd(s, 1);
432     if (cmdlen > 0) {
433         trace_esp_handle_satn_stop(fifo8_num_used(&s->cmdfifo));
434         s->do_cmd = 1;
435         s->cmdfifo_cdb_offset = 1;
436         s->rregs[ESP_RSTAT] = STAT_MO;
437         s->rregs[ESP_RINTR] |= INTR_BS | INTR_FC;
438         s->rregs[ESP_RSEQ] = SEQ_MO;
439         esp_raise_irq(s);
440     } else if (cmdlen == 0) {
441         s->do_cmd = 1;
442         /* Target present, switch to message out phase */
443         s->rregs[ESP_RSEQ] = SEQ_MO;
444         s->rregs[ESP_RSTAT] = STAT_MO;
445     }
446 }
447 
448 static void write_response_pdma_cb(ESPState *s)
449 {
450     s->rregs[ESP_RSTAT] = STAT_TC | STAT_ST;
451     s->rregs[ESP_RINTR] |= INTR_BS | INTR_FC;
452     s->rregs[ESP_RSEQ] = SEQ_CD;
453     esp_raise_irq(s);
454 }
455 
456 static void write_response(ESPState *s)
457 {
458     uint8_t buf[2];
459 
460     trace_esp_write_response(s->status);
461 
462     buf[0] = s->status;
463     buf[1] = 0;
464 
465     if (s->dma) {
466         if (s->dma_memory_write) {
467             s->dma_memory_write(s->dma_opaque, buf, 2);
468             s->rregs[ESP_RSTAT] = STAT_TC | STAT_ST;
469             s->rregs[ESP_RINTR] |= INTR_BS | INTR_FC;
470             s->rregs[ESP_RSEQ] = SEQ_CD;
471         } else {
472             esp_set_pdma_cb(s, WRITE_RESPONSE_PDMA_CB);
473             esp_raise_drq(s);
474             return;
475         }
476     } else {
477         fifo8_reset(&s->fifo);
478         fifo8_push_all(&s->fifo, buf, 2);
479         s->rregs[ESP_RFLAGS] = 2;
480     }
481     esp_raise_irq(s);
482 }
483 
484 static void esp_dma_done(ESPState *s)
485 {
486     s->rregs[ESP_RSTAT] |= STAT_TC;
487     s->rregs[ESP_RINTR] |= INTR_BS;
488     s->rregs[ESP_RFLAGS] = 0;
489     esp_set_tc(s, 0);
490     esp_raise_irq(s);
491 }
492 
493 static void do_dma_pdma_cb(ESPState *s)
494 {
495     int to_device = ((s->rregs[ESP_RSTAT] & 7) == STAT_DO);
496     int len;
497     uint32_t n;
498 
499     if (s->do_cmd) {
500         /* Ensure we have received complete command after SATN and stop */
501         if (esp_get_tc(s) || fifo8_is_empty(&s->cmdfifo)) {
502             return;
503         }
504 
505         s->ti_size = 0;
506         if ((s->rregs[ESP_RSTAT] & 7) == STAT_CD) {
507             /* No command received */
508             if (s->cmdfifo_cdb_offset == fifo8_num_used(&s->cmdfifo)) {
509                 return;
510             }
511 
512             /* Command has been received */
513             s->do_cmd = 0;
514             do_cmd(s);
515         } else {
516             /*
517              * Extra message out bytes received: update cmdfifo_cdb_offset
518              * and then switch to command phase
519              */
520             s->cmdfifo_cdb_offset = fifo8_num_used(&s->cmdfifo);
521             s->rregs[ESP_RSTAT] = STAT_TC | STAT_CD;
522             s->rregs[ESP_RSEQ] = SEQ_CD;
523             s->rregs[ESP_RINTR] |= INTR_BS;
524             esp_raise_irq(s);
525         }
526         return;
527     }
528 
529     if (!s->current_req) {
530         return;
531     }
532 
533     if (to_device) {
534         /* Copy FIFO data to device */
535         len = MIN(s->async_len, ESP_FIFO_SZ);
536         len = MIN(len, fifo8_num_used(&s->fifo));
537         n = esp_fifo_pop_buf(&s->fifo, s->async_buf, len);
538         s->async_buf += n;
539         s->async_len -= n;
540         s->ti_size += n;
541 
542         if (n < len) {
543             /* Unaligned accesses can cause FIFO wraparound */
544             len = len - n;
545             n = esp_fifo_pop_buf(&s->fifo, s->async_buf, len);
546             s->async_buf += n;
547             s->async_len -= n;
548             s->ti_size += n;
549         }
550 
551         if (s->async_len == 0) {
552             scsi_req_continue(s->current_req);
553             return;
554         }
555 
556         if (esp_get_tc(s) == 0) {
557             esp_lower_drq(s);
558             esp_dma_done(s);
559         }
560 
561         return;
562     } else {
563         if (s->async_len == 0) {
564             /* Defer until the scsi layer has completed */
565             scsi_req_continue(s->current_req);
566             s->data_in_ready = false;
567             return;
568         }
569 
570         if (esp_get_tc(s) != 0) {
571             /* Copy device data to FIFO */
572             len = MIN(s->async_len, esp_get_tc(s));
573             len = MIN(len, fifo8_num_free(&s->fifo));
574             fifo8_push_all(&s->fifo, s->async_buf, len);
575             s->async_buf += len;
576             s->async_len -= len;
577             s->ti_size -= len;
578             esp_set_tc(s, esp_get_tc(s) - len);
579 
580             if (esp_get_tc(s) == 0) {
581                 /* Indicate transfer to FIFO is complete */
582                  s->rregs[ESP_RSTAT] |= STAT_TC;
583             }
584             return;
585         }
586 
587         /* Partially filled a scsi buffer. Complete immediately.  */
588         esp_lower_drq(s);
589         esp_dma_done(s);
590     }
591 }
592 
593 static void esp_do_dma(ESPState *s)
594 {
595     uint32_t len, cmdlen;
596     int to_device = ((s->rregs[ESP_RSTAT] & 7) == STAT_DO);
597     uint8_t buf[ESP_CMDFIFO_SZ];
598 
599     len = esp_get_tc(s);
600     if (s->do_cmd) {
601         /*
602          * handle_ti_cmd() case: esp_do_dma() is called only from
603          * handle_ti_cmd() with do_cmd != NULL (see the assert())
604          */
605         cmdlen = fifo8_num_used(&s->cmdfifo);
606         trace_esp_do_dma(cmdlen, len);
607         if (s->dma_memory_read) {
608             len = MIN(len, fifo8_num_free(&s->cmdfifo));
609             s->dma_memory_read(s->dma_opaque, buf, len);
610             fifo8_push_all(&s->cmdfifo, buf, len);
611         } else {
612             esp_set_pdma_cb(s, DO_DMA_PDMA_CB);
613             esp_raise_drq(s);
614             return;
615         }
616         trace_esp_handle_ti_cmd(cmdlen);
617         s->ti_size = 0;
618         if ((s->rregs[ESP_RSTAT] & 7) == STAT_CD) {
619             /* No command received */
620             if (s->cmdfifo_cdb_offset == fifo8_num_used(&s->cmdfifo)) {
621                 return;
622             }
623 
624             /* Command has been received */
625             s->do_cmd = 0;
626             do_cmd(s);
627         } else {
628             /*
629              * Extra message out bytes received: update cmdfifo_cdb_offset
630              * and then switch to command phase
631              */
632             s->cmdfifo_cdb_offset = fifo8_num_used(&s->cmdfifo);
633             s->rregs[ESP_RSTAT] = STAT_TC | STAT_CD;
634             s->rregs[ESP_RSEQ] = SEQ_CD;
635             s->rregs[ESP_RINTR] |= INTR_BS;
636             esp_raise_irq(s);
637         }
638         return;
639     }
640     if (!s->current_req) {
641         return;
642     }
643     if (s->async_len == 0) {
644         /* Defer until data is available.  */
645         return;
646     }
647     if (len > s->async_len) {
648         len = s->async_len;
649     }
650     if (to_device) {
651         if (s->dma_memory_read) {
652             s->dma_memory_read(s->dma_opaque, s->async_buf, len);
653         } else {
654             esp_set_pdma_cb(s, DO_DMA_PDMA_CB);
655             esp_raise_drq(s);
656             return;
657         }
658     } else {
659         if (s->dma_memory_write) {
660             s->dma_memory_write(s->dma_opaque, s->async_buf, len);
661         } else {
662             /* Adjust TC for any leftover data in the FIFO */
663             if (!fifo8_is_empty(&s->fifo)) {
664                 esp_set_tc(s, esp_get_tc(s) - fifo8_num_used(&s->fifo));
665             }
666 
667             /* Copy device data to FIFO */
668             len = MIN(len, fifo8_num_free(&s->fifo));
669             fifo8_push_all(&s->fifo, s->async_buf, len);
670             s->async_buf += len;
671             s->async_len -= len;
672             s->ti_size -= len;
673 
674             /*
675              * MacOS toolbox uses a TI length of 16 bytes for all commands, so
676              * commands shorter than this must be padded accordingly
677              */
678             if (len < esp_get_tc(s) && esp_get_tc(s) <= ESP_FIFO_SZ) {
679                 while (fifo8_num_used(&s->fifo) < ESP_FIFO_SZ) {
680                     esp_fifo_push(&s->fifo, 0);
681                     len++;
682                 }
683             }
684 
685             esp_set_tc(s, esp_get_tc(s) - len);
686             esp_set_pdma_cb(s, DO_DMA_PDMA_CB);
687             esp_raise_drq(s);
688 
689             /* Indicate transfer to FIFO is complete */
690             s->rregs[ESP_RSTAT] |= STAT_TC;
691             return;
692         }
693     }
694     esp_set_tc(s, esp_get_tc(s) - len);
695     s->async_buf += len;
696     s->async_len -= len;
697     if (to_device) {
698         s->ti_size += len;
699     } else {
700         s->ti_size -= len;
701     }
702     if (s->async_len == 0) {
703         scsi_req_continue(s->current_req);
704         /*
705          * If there is still data to be read from the device then
706          * complete the DMA operation immediately.  Otherwise defer
707          * until the scsi layer has completed.
708          */
709         if (to_device || esp_get_tc(s) != 0 || s->ti_size == 0) {
710             return;
711         }
712     }
713 
714     /* Partially filled a scsi buffer. Complete immediately.  */
715     esp_dma_done(s);
716     esp_lower_drq(s);
717 }
718 
719 static void esp_do_nodma(ESPState *s)
720 {
721     int to_device = ((s->rregs[ESP_RSTAT] & 7) == STAT_DO);
722     uint32_t cmdlen;
723     int len;
724 
725     if (s->do_cmd) {
726         cmdlen = fifo8_num_used(&s->cmdfifo);
727         trace_esp_handle_ti_cmd(cmdlen);
728         s->ti_size = 0;
729         if ((s->rregs[ESP_RSTAT] & 7) == STAT_CD) {
730             /* No command received */
731             if (s->cmdfifo_cdb_offset == fifo8_num_used(&s->cmdfifo)) {
732                 return;
733             }
734 
735             /* Command has been received */
736             s->do_cmd = 0;
737             do_cmd(s);
738         } else {
739             /*
740              * Extra message out bytes received: update cmdfifo_cdb_offset
741              * and then switch to command phase
742              */
743             s->cmdfifo_cdb_offset = fifo8_num_used(&s->cmdfifo);
744             s->rregs[ESP_RSTAT] = STAT_TC | STAT_CD;
745             s->rregs[ESP_RSEQ] = SEQ_CD;
746             s->rregs[ESP_RINTR] |= INTR_BS;
747             esp_raise_irq(s);
748         }
749         return;
750     }
751 
752     if (!s->current_req) {
753         return;
754     }
755 
756     if (s->async_len == 0) {
757         /* Defer until data is available.  */
758         return;
759     }
760 
761     if (to_device) {
762         len = MIN(fifo8_num_used(&s->fifo), ESP_FIFO_SZ);
763         esp_fifo_pop_buf(&s->fifo, s->async_buf, len);
764         s->async_buf += len;
765         s->async_len -= len;
766         s->ti_size += len;
767     } else {
768         if (fifo8_is_empty(&s->fifo)) {
769             fifo8_push(&s->fifo, s->async_buf[0]);
770             s->async_buf++;
771             s->async_len--;
772             s->ti_size--;
773         }
774     }
775 
776     if (s->async_len == 0) {
777         scsi_req_continue(s->current_req);
778         return;
779     }
780 
781     s->rregs[ESP_RINTR] |= INTR_BS;
782     esp_raise_irq(s);
783 }
784 
785 static void esp_pdma_cb(ESPState *s)
786 {
787     switch (s->pdma_cb) {
788     case SATN_PDMA_CB:
789         satn_pdma_cb(s);
790         break;
791     case S_WITHOUT_SATN_PDMA_CB:
792         s_without_satn_pdma_cb(s);
793         break;
794     case SATN_STOP_PDMA_CB:
795         satn_stop_pdma_cb(s);
796         break;
797     case WRITE_RESPONSE_PDMA_CB:
798         write_response_pdma_cb(s);
799         break;
800     case DO_DMA_PDMA_CB:
801         do_dma_pdma_cb(s);
802         break;
803     default:
804         g_assert_not_reached();
805     }
806 }
807 
808 void esp_command_complete(SCSIRequest *req, size_t resid)
809 {
810     ESPState *s = req->hba_private;
811     int to_device = ((s->rregs[ESP_RSTAT] & 7) == STAT_DO);
812 
813     trace_esp_command_complete();
814 
815     /*
816      * Non-DMA transfers from the target will leave the last byte in
817      * the FIFO so don't reset ti_size in this case
818      */
819     if (s->dma || to_device) {
820         if (s->ti_size != 0) {
821             trace_esp_command_complete_unexpected();
822         }
823         s->ti_size = 0;
824     }
825 
826     s->async_len = 0;
827     if (req->status) {
828         trace_esp_command_complete_fail();
829     }
830     s->status = req->status;
831 
832     /*
833      * If the transfer is finished, switch to status phase. For non-DMA
834      * transfers from the target the last byte is still in the FIFO
835      */
836     if (s->ti_size == 0) {
837         s->rregs[ESP_RSTAT] = STAT_TC | STAT_ST;
838         esp_dma_done(s);
839         esp_lower_drq(s);
840     }
841 
842     if (s->current_req) {
843         scsi_req_unref(s->current_req);
844         s->current_req = NULL;
845         s->current_dev = NULL;
846     }
847 }
848 
849 void esp_transfer_data(SCSIRequest *req, uint32_t len)
850 {
851     ESPState *s = req->hba_private;
852     int to_device = ((s->rregs[ESP_RSTAT] & 7) == STAT_DO);
853     uint32_t dmalen = esp_get_tc(s);
854 
855     assert(!s->do_cmd);
856     trace_esp_transfer_data(dmalen, s->ti_size);
857     s->async_len = len;
858     s->async_buf = scsi_req_get_buf(req);
859 
860     if (!to_device && !s->data_in_ready) {
861         /*
862          * Initial incoming data xfer is complete so raise command
863          * completion interrupt
864          */
865         s->data_in_ready = true;
866         s->rregs[ESP_RSTAT] |= STAT_TC;
867         s->rregs[ESP_RINTR] |= INTR_BS;
868         esp_raise_irq(s);
869     }
870 
871     if (s->ti_cmd == 0) {
872         /*
873          * Always perform the initial transfer upon reception of the next TI
874          * command to ensure the DMA/non-DMA status of the command is correct.
875          * It is not possible to use s->dma directly in the section below as
876          * some OSs send non-DMA NOP commands after a DMA transfer. Hence if the
877          * async data transfer is delayed then s->dma is set incorrectly.
878          */
879         return;
880     }
881 
882     if (s->ti_cmd == (CMD_TI | CMD_DMA)) {
883         if (dmalen) {
884             esp_do_dma(s);
885         } else if (s->ti_size <= 0) {
886             /*
887              * If this was the last part of a DMA transfer then the
888              * completion interrupt is deferred to here.
889              */
890             esp_dma_done(s);
891             esp_lower_drq(s);
892         }
893     } else if (s->ti_cmd == CMD_TI) {
894         esp_do_nodma(s);
895     }
896 }
897 
898 static void handle_ti(ESPState *s)
899 {
900     uint32_t dmalen;
901 
902     if (s->dma && !s->dma_enabled) {
903         s->dma_cb = handle_ti;
904         return;
905     }
906 
907     s->ti_cmd = s->rregs[ESP_CMD];
908     if (s->dma) {
909         dmalen = esp_get_tc(s);
910         trace_esp_handle_ti(dmalen);
911         s->rregs[ESP_RSTAT] &= ~STAT_TC;
912         esp_do_dma(s);
913     } else {
914         trace_esp_handle_ti(s->ti_size);
915         esp_do_nodma(s);
916     }
917 }
918 
919 void esp_hard_reset(ESPState *s)
920 {
921     memset(s->rregs, 0, ESP_REGS);
922     memset(s->wregs, 0, ESP_REGS);
923     s->tchi_written = 0;
924     s->ti_size = 0;
925     s->async_len = 0;
926     fifo8_reset(&s->fifo);
927     fifo8_reset(&s->cmdfifo);
928     s->dma = 0;
929     s->do_cmd = 0;
930     s->dma_cb = NULL;
931 
932     s->rregs[ESP_CFG1] = 7;
933 }
934 
935 static void esp_soft_reset(ESPState *s)
936 {
937     qemu_irq_lower(s->irq);
938     qemu_irq_lower(s->irq_data);
939     esp_hard_reset(s);
940 }
941 
942 static void esp_bus_reset(ESPState *s)
943 {
944     bus_cold_reset(BUS(&s->bus));
945 }
946 
947 static void parent_esp_reset(ESPState *s, int irq, int level)
948 {
949     if (level) {
950         esp_soft_reset(s);
951     }
952 }
953 
954 uint64_t esp_reg_read(ESPState *s, uint32_t saddr)
955 {
956     uint32_t val;
957 
958     switch (saddr) {
959     case ESP_FIFO:
960         if (s->dma_memory_read && s->dma_memory_write &&
961                 (s->rregs[ESP_RSTAT] & STAT_PIO_MASK) == 0) {
962             /* Data out.  */
963             qemu_log_mask(LOG_UNIMP, "esp: PIO data read not implemented\n");
964             s->rregs[ESP_FIFO] = 0;
965         } else {
966             if ((s->rregs[ESP_RSTAT] & 0x7) == STAT_DI) {
967                 if (s->ti_size) {
968                     esp_do_nodma(s);
969                 } else {
970                     /*
971                      * The last byte of a non-DMA transfer has been read out
972                      * of the FIFO so switch to status phase
973                      */
974                     s->rregs[ESP_RSTAT] = STAT_TC | STAT_ST;
975                 }
976             }
977             s->rregs[ESP_FIFO] = esp_fifo_pop(&s->fifo);
978         }
979         val = s->rregs[ESP_FIFO];
980         break;
981     case ESP_RINTR:
982         /*
983          * Clear sequence step, interrupt register and all status bits
984          * except TC
985          */
986         val = s->rregs[ESP_RINTR];
987         s->rregs[ESP_RINTR] = 0;
988         s->rregs[ESP_RSTAT] &= ~STAT_TC;
989         /*
990          * According to the datasheet ESP_RSEQ should be cleared, but as the
991          * emulation currently defers information transfers to the next TI
992          * command leave it for now so that pedantic guests such as the old
993          * Linux 2.6 driver see the correct flags before the next SCSI phase
994          * transition.
995          *
996          * s->rregs[ESP_RSEQ] = SEQ_0;
997          */
998         esp_lower_irq(s);
999         break;
1000     case ESP_TCHI:
1001         /* Return the unique id if the value has never been written */
1002         if (!s->tchi_written) {
1003             val = s->chip_id;
1004         } else {
1005             val = s->rregs[saddr];
1006         }
1007         break;
1008      case ESP_RFLAGS:
1009         /* Bottom 5 bits indicate number of bytes in FIFO */
1010         val = fifo8_num_used(&s->fifo);
1011         break;
1012     default:
1013         val = s->rregs[saddr];
1014         break;
1015     }
1016 
1017     trace_esp_mem_readb(saddr, val);
1018     return val;
1019 }
1020 
1021 void esp_reg_write(ESPState *s, uint32_t saddr, uint64_t val)
1022 {
1023     trace_esp_mem_writeb(saddr, s->wregs[saddr], val);
1024     switch (saddr) {
1025     case ESP_TCHI:
1026         s->tchi_written = true;
1027         /* fall through */
1028     case ESP_TCLO:
1029     case ESP_TCMID:
1030         s->rregs[ESP_RSTAT] &= ~STAT_TC;
1031         break;
1032     case ESP_FIFO:
1033         if (s->do_cmd) {
1034             esp_fifo_push(&s->cmdfifo, val);
1035 
1036             /*
1037              * If any unexpected message out/command phase data is
1038              * transferred using non-DMA, raise the interrupt
1039              */
1040             if (s->rregs[ESP_CMD] == CMD_TI) {
1041                 s->rregs[ESP_RINTR] |= INTR_BS;
1042                 esp_raise_irq(s);
1043             }
1044         } else {
1045             esp_fifo_push(&s->fifo, val);
1046         }
1047         break;
1048     case ESP_CMD:
1049         s->rregs[saddr] = val;
1050         if (val & CMD_DMA) {
1051             s->dma = 1;
1052             /* Reload DMA counter.  */
1053             if (esp_get_stc(s) == 0) {
1054                 esp_set_tc(s, 0x10000);
1055             } else {
1056                 esp_set_tc(s, esp_get_stc(s));
1057             }
1058         } else {
1059             s->dma = 0;
1060         }
1061         switch (val & CMD_CMD) {
1062         case CMD_NOP:
1063             trace_esp_mem_writeb_cmd_nop(val);
1064             break;
1065         case CMD_FLUSH:
1066             trace_esp_mem_writeb_cmd_flush(val);
1067             fifo8_reset(&s->fifo);
1068             break;
1069         case CMD_RESET:
1070             trace_esp_mem_writeb_cmd_reset(val);
1071             esp_soft_reset(s);
1072             break;
1073         case CMD_BUSRESET:
1074             trace_esp_mem_writeb_cmd_bus_reset(val);
1075             esp_bus_reset(s);
1076             if (!(s->wregs[ESP_CFG1] & CFG1_RESREPT)) {
1077                 s->rregs[ESP_RINTR] |= INTR_RST;
1078                 esp_raise_irq(s);
1079             }
1080             break;
1081         case CMD_TI:
1082             trace_esp_mem_writeb_cmd_ti(val);
1083             handle_ti(s);
1084             break;
1085         case CMD_ICCS:
1086             trace_esp_mem_writeb_cmd_iccs(val);
1087             write_response(s);
1088             s->rregs[ESP_RINTR] |= INTR_FC;
1089             s->rregs[ESP_RSTAT] |= STAT_MI;
1090             break;
1091         case CMD_MSGACC:
1092             trace_esp_mem_writeb_cmd_msgacc(val);
1093             s->rregs[ESP_RINTR] |= INTR_DC;
1094             s->rregs[ESP_RSEQ] = 0;
1095             s->rregs[ESP_RFLAGS] = 0;
1096             esp_raise_irq(s);
1097             break;
1098         case CMD_PAD:
1099             trace_esp_mem_writeb_cmd_pad(val);
1100             s->rregs[ESP_RSTAT] = STAT_TC;
1101             s->rregs[ESP_RINTR] |= INTR_FC;
1102             s->rregs[ESP_RSEQ] = 0;
1103             break;
1104         case CMD_SATN:
1105             trace_esp_mem_writeb_cmd_satn(val);
1106             break;
1107         case CMD_RSTATN:
1108             trace_esp_mem_writeb_cmd_rstatn(val);
1109             break;
1110         case CMD_SEL:
1111             trace_esp_mem_writeb_cmd_sel(val);
1112             handle_s_without_atn(s);
1113             break;
1114         case CMD_SELATN:
1115             trace_esp_mem_writeb_cmd_selatn(val);
1116             handle_satn(s);
1117             break;
1118         case CMD_SELATNS:
1119             trace_esp_mem_writeb_cmd_selatns(val);
1120             handle_satn_stop(s);
1121             break;
1122         case CMD_ENSEL:
1123             trace_esp_mem_writeb_cmd_ensel(val);
1124             s->rregs[ESP_RINTR] = 0;
1125             break;
1126         case CMD_DISSEL:
1127             trace_esp_mem_writeb_cmd_dissel(val);
1128             s->rregs[ESP_RINTR] = 0;
1129             esp_raise_irq(s);
1130             break;
1131         default:
1132             trace_esp_error_unhandled_command(val);
1133             break;
1134         }
1135         break;
1136     case ESP_WBUSID ... ESP_WSYNO:
1137         break;
1138     case ESP_CFG1:
1139     case ESP_CFG2: case ESP_CFG3:
1140     case ESP_RES3: case ESP_RES4:
1141         s->rregs[saddr] = val;
1142         break;
1143     case ESP_WCCF ... ESP_WTEST:
1144         break;
1145     default:
1146         trace_esp_error_invalid_write(val, saddr);
1147         return;
1148     }
1149     s->wregs[saddr] = val;
1150 }
1151 
1152 static bool esp_mem_accepts(void *opaque, hwaddr addr,
1153                             unsigned size, bool is_write,
1154                             MemTxAttrs attrs)
1155 {
1156     return (size == 1) || (is_write && size == 4);
1157 }
1158 
1159 static bool esp_is_before_version_5(void *opaque, int version_id)
1160 {
1161     ESPState *s = ESP(opaque);
1162 
1163     version_id = MIN(version_id, s->mig_version_id);
1164     return version_id < 5;
1165 }
1166 
1167 static bool esp_is_version_5(void *opaque, int version_id)
1168 {
1169     ESPState *s = ESP(opaque);
1170 
1171     version_id = MIN(version_id, s->mig_version_id);
1172     return version_id >= 5;
1173 }
1174 
1175 static bool esp_is_version_6(void *opaque, int version_id)
1176 {
1177     ESPState *s = ESP(opaque);
1178 
1179     version_id = MIN(version_id, s->mig_version_id);
1180     return version_id >= 6;
1181 }
1182 
1183 int esp_pre_save(void *opaque)
1184 {
1185     ESPState *s = ESP(object_resolve_path_component(
1186                       OBJECT(opaque), "esp"));
1187 
1188     s->mig_version_id = vmstate_esp.version_id;
1189     return 0;
1190 }
1191 
1192 static int esp_post_load(void *opaque, int version_id)
1193 {
1194     ESPState *s = ESP(opaque);
1195     int len, i;
1196 
1197     version_id = MIN(version_id, s->mig_version_id);
1198 
1199     if (version_id < 5) {
1200         esp_set_tc(s, s->mig_dma_left);
1201 
1202         /* Migrate ti_buf to fifo */
1203         len = s->mig_ti_wptr - s->mig_ti_rptr;
1204         for (i = 0; i < len; i++) {
1205             fifo8_push(&s->fifo, s->mig_ti_buf[i]);
1206         }
1207 
1208         /* Migrate cmdbuf to cmdfifo */
1209         for (i = 0; i < s->mig_cmdlen; i++) {
1210             fifo8_push(&s->cmdfifo, s->mig_cmdbuf[i]);
1211         }
1212     }
1213 
1214     s->mig_version_id = vmstate_esp.version_id;
1215     return 0;
1216 }
1217 
1218 /*
1219  * PDMA (or pseudo-DMA) is only used on the Macintosh and requires the
1220  * guest CPU to perform the transfers between the SCSI bus and memory
1221  * itself. This is indicated by the dma_memory_read and dma_memory_write
1222  * functions being NULL (in contrast to the ESP PCI device) whilst
1223  * dma_enabled is still set.
1224  */
1225 
1226 static bool esp_pdma_needed(void *opaque)
1227 {
1228     ESPState *s = ESP(opaque);
1229 
1230     return s->dma_memory_read == NULL && s->dma_memory_write == NULL &&
1231            s->dma_enabled;
1232 }
1233 
1234 static const VMStateDescription vmstate_esp_pdma = {
1235     .name = "esp/pdma",
1236     .version_id = 0,
1237     .minimum_version_id = 0,
1238     .needed = esp_pdma_needed,
1239     .fields = (VMStateField[]) {
1240         VMSTATE_UINT8(pdma_cb, ESPState),
1241         VMSTATE_END_OF_LIST()
1242     }
1243 };
1244 
1245 const VMStateDescription vmstate_esp = {
1246     .name = "esp",
1247     .version_id = 6,
1248     .minimum_version_id = 3,
1249     .post_load = esp_post_load,
1250     .fields = (VMStateField[]) {
1251         VMSTATE_BUFFER(rregs, ESPState),
1252         VMSTATE_BUFFER(wregs, ESPState),
1253         VMSTATE_INT32(ti_size, ESPState),
1254         VMSTATE_UINT32_TEST(mig_ti_rptr, ESPState, esp_is_before_version_5),
1255         VMSTATE_UINT32_TEST(mig_ti_wptr, ESPState, esp_is_before_version_5),
1256         VMSTATE_BUFFER_TEST(mig_ti_buf, ESPState, esp_is_before_version_5),
1257         VMSTATE_UINT32(status, ESPState),
1258         VMSTATE_UINT32_TEST(mig_deferred_status, ESPState,
1259                             esp_is_before_version_5),
1260         VMSTATE_BOOL_TEST(mig_deferred_complete, ESPState,
1261                           esp_is_before_version_5),
1262         VMSTATE_UINT32(dma, ESPState),
1263         VMSTATE_STATIC_BUFFER(mig_cmdbuf, ESPState, 0,
1264                               esp_is_before_version_5, 0, 16),
1265         VMSTATE_STATIC_BUFFER(mig_cmdbuf, ESPState, 4,
1266                               esp_is_before_version_5, 16,
1267                               sizeof(typeof_field(ESPState, mig_cmdbuf))),
1268         VMSTATE_UINT32_TEST(mig_cmdlen, ESPState, esp_is_before_version_5),
1269         VMSTATE_UINT32(do_cmd, ESPState),
1270         VMSTATE_UINT32_TEST(mig_dma_left, ESPState, esp_is_before_version_5),
1271         VMSTATE_BOOL_TEST(data_in_ready, ESPState, esp_is_version_5),
1272         VMSTATE_UINT8_TEST(cmdfifo_cdb_offset, ESPState, esp_is_version_5),
1273         VMSTATE_FIFO8_TEST(fifo, ESPState, esp_is_version_5),
1274         VMSTATE_FIFO8_TEST(cmdfifo, ESPState, esp_is_version_5),
1275         VMSTATE_UINT8_TEST(ti_cmd, ESPState, esp_is_version_5),
1276         VMSTATE_UINT8_TEST(lun, ESPState, esp_is_version_6),
1277         VMSTATE_END_OF_LIST()
1278     },
1279     .subsections = (const VMStateDescription * []) {
1280         &vmstate_esp_pdma,
1281         NULL
1282     }
1283 };
1284 
1285 static void sysbus_esp_mem_write(void *opaque, hwaddr addr,
1286                                  uint64_t val, unsigned int size)
1287 {
1288     SysBusESPState *sysbus = opaque;
1289     ESPState *s = ESP(&sysbus->esp);
1290     uint32_t saddr;
1291 
1292     saddr = addr >> sysbus->it_shift;
1293     esp_reg_write(s, saddr, val);
1294 }
1295 
1296 static uint64_t sysbus_esp_mem_read(void *opaque, hwaddr addr,
1297                                     unsigned int size)
1298 {
1299     SysBusESPState *sysbus = opaque;
1300     ESPState *s = ESP(&sysbus->esp);
1301     uint32_t saddr;
1302 
1303     saddr = addr >> sysbus->it_shift;
1304     return esp_reg_read(s, saddr);
1305 }
1306 
1307 static const MemoryRegionOps sysbus_esp_mem_ops = {
1308     .read = sysbus_esp_mem_read,
1309     .write = sysbus_esp_mem_write,
1310     .endianness = DEVICE_NATIVE_ENDIAN,
1311     .valid.accepts = esp_mem_accepts,
1312 };
1313 
1314 static void sysbus_esp_pdma_write(void *opaque, hwaddr addr,
1315                                   uint64_t val, unsigned int size)
1316 {
1317     SysBusESPState *sysbus = opaque;
1318     ESPState *s = ESP(&sysbus->esp);
1319 
1320     trace_esp_pdma_write(size);
1321 
1322     switch (size) {
1323     case 1:
1324         esp_pdma_write(s, val);
1325         break;
1326     case 2:
1327         esp_pdma_write(s, val >> 8);
1328         esp_pdma_write(s, val);
1329         break;
1330     }
1331     esp_pdma_cb(s);
1332 }
1333 
1334 static uint64_t sysbus_esp_pdma_read(void *opaque, hwaddr addr,
1335                                      unsigned int size)
1336 {
1337     SysBusESPState *sysbus = opaque;
1338     ESPState *s = ESP(&sysbus->esp);
1339     uint64_t val = 0;
1340 
1341     trace_esp_pdma_read(size);
1342 
1343     switch (size) {
1344     case 1:
1345         val = esp_pdma_read(s);
1346         break;
1347     case 2:
1348         val = esp_pdma_read(s);
1349         val = (val << 8) | esp_pdma_read(s);
1350         break;
1351     }
1352     if (fifo8_num_used(&s->fifo) < 2) {
1353         esp_pdma_cb(s);
1354     }
1355     return val;
1356 }
1357 
1358 static void *esp_load_request(QEMUFile *f, SCSIRequest *req)
1359 {
1360     ESPState *s = container_of(req->bus, ESPState, bus);
1361 
1362     scsi_req_ref(req);
1363     s->current_req = req;
1364     return s;
1365 }
1366 
1367 static const MemoryRegionOps sysbus_esp_pdma_ops = {
1368     .read = sysbus_esp_pdma_read,
1369     .write = sysbus_esp_pdma_write,
1370     .endianness = DEVICE_NATIVE_ENDIAN,
1371     .valid.min_access_size = 1,
1372     .valid.max_access_size = 4,
1373     .impl.min_access_size = 1,
1374     .impl.max_access_size = 2,
1375 };
1376 
1377 static const struct SCSIBusInfo esp_scsi_info = {
1378     .tcq = false,
1379     .max_target = ESP_MAX_DEVS,
1380     .max_lun = 7,
1381 
1382     .load_request = esp_load_request,
1383     .transfer_data = esp_transfer_data,
1384     .complete = esp_command_complete,
1385     .cancel = esp_request_cancelled
1386 };
1387 
1388 static void sysbus_esp_gpio_demux(void *opaque, int irq, int level)
1389 {
1390     SysBusESPState *sysbus = SYSBUS_ESP(opaque);
1391     ESPState *s = ESP(&sysbus->esp);
1392 
1393     switch (irq) {
1394     case 0:
1395         parent_esp_reset(s, irq, level);
1396         break;
1397     case 1:
1398         esp_dma_enable(opaque, irq, level);
1399         break;
1400     }
1401 }
1402 
1403 static void sysbus_esp_realize(DeviceState *dev, Error **errp)
1404 {
1405     SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
1406     SysBusESPState *sysbus = SYSBUS_ESP(dev);
1407     ESPState *s = ESP(&sysbus->esp);
1408 
1409     if (!qdev_realize(DEVICE(s), NULL, errp)) {
1410         return;
1411     }
1412 
1413     sysbus_init_irq(sbd, &s->irq);
1414     sysbus_init_irq(sbd, &s->irq_data);
1415     assert(sysbus->it_shift != -1);
1416 
1417     s->chip_id = TCHI_FAS100A;
1418     memory_region_init_io(&sysbus->iomem, OBJECT(sysbus), &sysbus_esp_mem_ops,
1419                           sysbus, "esp-regs", ESP_REGS << sysbus->it_shift);
1420     sysbus_init_mmio(sbd, &sysbus->iomem);
1421     memory_region_init_io(&sysbus->pdma, OBJECT(sysbus), &sysbus_esp_pdma_ops,
1422                           sysbus, "esp-pdma", 4);
1423     sysbus_init_mmio(sbd, &sysbus->pdma);
1424 
1425     qdev_init_gpio_in(dev, sysbus_esp_gpio_demux, 2);
1426 
1427     scsi_bus_init(&s->bus, sizeof(s->bus), dev, &esp_scsi_info);
1428 }
1429 
1430 static void sysbus_esp_hard_reset(DeviceState *dev)
1431 {
1432     SysBusESPState *sysbus = SYSBUS_ESP(dev);
1433     ESPState *s = ESP(&sysbus->esp);
1434 
1435     esp_hard_reset(s);
1436 }
1437 
1438 static void sysbus_esp_init(Object *obj)
1439 {
1440     SysBusESPState *sysbus = SYSBUS_ESP(obj);
1441 
1442     object_initialize_child(obj, "esp", &sysbus->esp, TYPE_ESP);
1443 }
1444 
1445 static const VMStateDescription vmstate_sysbus_esp_scsi = {
1446     .name = "sysbusespscsi",
1447     .version_id = 2,
1448     .minimum_version_id = 1,
1449     .pre_save = esp_pre_save,
1450     .fields = (VMStateField[]) {
1451         VMSTATE_UINT8_V(esp.mig_version_id, SysBusESPState, 2),
1452         VMSTATE_STRUCT(esp, SysBusESPState, 0, vmstate_esp, ESPState),
1453         VMSTATE_END_OF_LIST()
1454     }
1455 };
1456 
1457 static void sysbus_esp_class_init(ObjectClass *klass, void *data)
1458 {
1459     DeviceClass *dc = DEVICE_CLASS(klass);
1460 
1461     dc->realize = sysbus_esp_realize;
1462     dc->reset = sysbus_esp_hard_reset;
1463     dc->vmsd = &vmstate_sysbus_esp_scsi;
1464     set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
1465 }
1466 
1467 static const TypeInfo sysbus_esp_info = {
1468     .name          = TYPE_SYSBUS_ESP,
1469     .parent        = TYPE_SYS_BUS_DEVICE,
1470     .instance_init = sysbus_esp_init,
1471     .instance_size = sizeof(SysBusESPState),
1472     .class_init    = sysbus_esp_class_init,
1473 };
1474 
1475 static void esp_finalize(Object *obj)
1476 {
1477     ESPState *s = ESP(obj);
1478 
1479     fifo8_destroy(&s->fifo);
1480     fifo8_destroy(&s->cmdfifo);
1481 }
1482 
1483 static void esp_init(Object *obj)
1484 {
1485     ESPState *s = ESP(obj);
1486 
1487     fifo8_create(&s->fifo, ESP_FIFO_SZ);
1488     fifo8_create(&s->cmdfifo, ESP_CMDFIFO_SZ);
1489 }
1490 
1491 static void esp_class_init(ObjectClass *klass, void *data)
1492 {
1493     DeviceClass *dc = DEVICE_CLASS(klass);
1494 
1495     /* internal device for sysbusesp/pciespscsi, not user-creatable */
1496     dc->user_creatable = false;
1497     set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
1498 }
1499 
1500 static const TypeInfo esp_info = {
1501     .name = TYPE_ESP,
1502     .parent = TYPE_DEVICE,
1503     .instance_init = esp_init,
1504     .instance_finalize = esp_finalize,
1505     .instance_size = sizeof(ESPState),
1506     .class_init = esp_class_init,
1507 };
1508 
1509 static void esp_register_types(void)
1510 {
1511     type_register_static(&sysbus_esp_info);
1512     type_register_static(&esp_info);
1513 }
1514 
1515 type_init(esp_register_types)
1516