xref: /qemu/hw/scsi/esp.c (revision c47b5835f5b8f971b10ecf5965117ffa3500d0ce)
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     }
99 }
100 
101 static uint32_t esp_get_tc(ESPState *s)
102 {
103     uint32_t dmalen;
104 
105     dmalen = s->rregs[ESP_TCLO];
106     dmalen |= s->rregs[ESP_TCMID] << 8;
107     dmalen |= s->rregs[ESP_TCHI] << 16;
108 
109     return dmalen;
110 }
111 
112 static void esp_set_tc(ESPState *s, uint32_t dmalen)
113 {
114     s->rregs[ESP_TCLO] = dmalen;
115     s->rregs[ESP_TCMID] = dmalen >> 8;
116     s->rregs[ESP_TCHI] = dmalen >> 16;
117 }
118 
119 static void set_pdma(ESPState *s, enum pdma_origin_id origin,
120                      uint32_t index, uint32_t len)
121 {
122     s->pdma_origin = origin;
123     s->pdma_start = index;
124     s->pdma_cur = index;
125     s->pdma_len = len;
126 }
127 
128 static uint8_t *get_pdma_buf(ESPState *s)
129 {
130     switch (s->pdma_origin) {
131     case PDMA:
132         return s->pdma_buf;
133     case TI:
134         return s->ti_buf;
135     case CMD:
136         return s->cmdbuf;
137     case ASYNC:
138         return s->async_buf;
139     }
140     return NULL;
141 }
142 
143 static int get_cmd_cb(ESPState *s)
144 {
145     int target;
146 
147     target = s->wregs[ESP_WBUSID] & BUSID_DID;
148 
149     s->ti_size = 0;
150     s->ti_rptr = 0;
151     s->ti_wptr = 0;
152 
153     if (s->current_req) {
154         /* Started a new command before the old one finished.  Cancel it.  */
155         scsi_req_cancel(s->current_req);
156         s->async_len = 0;
157     }
158 
159     s->current_dev = scsi_device_find(&s->bus, 0, target, 0);
160     if (!s->current_dev) {
161         /* No such drive */
162         s->rregs[ESP_RSTAT] = 0;
163         s->rregs[ESP_RINTR] = INTR_DC;
164         s->rregs[ESP_RSEQ] = SEQ_0;
165         esp_raise_irq(s);
166         return -1;
167     }
168     return 0;
169 }
170 
171 static uint32_t get_cmd(ESPState *s, uint8_t *buf, uint8_t buflen)
172 {
173     uint32_t dmalen;
174     int target;
175 
176     target = s->wregs[ESP_WBUSID] & BUSID_DID;
177     if (s->dma) {
178         dmalen = esp_get_tc(s);
179         if (dmalen > buflen) {
180             return 0;
181         }
182         if (s->dma_memory_read) {
183             s->dma_memory_read(s->dma_opaque, buf, dmalen);
184         } else {
185             memcpy(s->pdma_buf, buf, dmalen);
186             set_pdma(s, PDMA, 0, dmalen);
187             esp_raise_drq(s);
188             return 0;
189         }
190     } else {
191         dmalen = s->ti_size;
192         if (dmalen > TI_BUFSZ) {
193             return 0;
194         }
195         memcpy(buf, s->ti_buf, dmalen);
196         buf[0] = buf[2] >> 5;
197     }
198     trace_esp_get_cmd(dmalen, target);
199 
200     if (get_cmd_cb(s) < 0) {
201         return 0;
202     }
203     return dmalen;
204 }
205 
206 static void do_busid_cmd(ESPState *s, uint8_t *buf, uint8_t busid)
207 {
208     int32_t datalen;
209     int lun;
210     SCSIDevice *current_lun;
211 
212     trace_esp_do_busid_cmd(busid);
213     lun = busid & 7;
214     current_lun = scsi_device_find(&s->bus, 0, s->current_dev->id, lun);
215     s->current_req = scsi_req_new(current_lun, 0, lun, buf, s);
216     datalen = scsi_req_enqueue(s->current_req);
217     s->ti_size = datalen;
218     if (datalen != 0) {
219         s->rregs[ESP_RSTAT] = STAT_TC;
220         s->dma_left = 0;
221         s->dma_counter = 0;
222         if (datalen > 0) {
223             s->rregs[ESP_RSTAT] |= STAT_DI;
224         } else {
225             s->rregs[ESP_RSTAT] |= STAT_DO;
226         }
227         scsi_req_continue(s->current_req);
228     }
229     s->rregs[ESP_RINTR] = INTR_BS | INTR_FC;
230     s->rregs[ESP_RSEQ] = SEQ_CD;
231     esp_raise_irq(s);
232 }
233 
234 static void do_cmd(ESPState *s, uint8_t *buf)
235 {
236     uint8_t busid = buf[0];
237 
238     do_busid_cmd(s, &buf[1], busid);
239 }
240 
241 static void satn_pdma_cb(ESPState *s)
242 {
243     if (get_cmd_cb(s) < 0) {
244         return;
245     }
246     if (s->pdma_cur != s->pdma_start) {
247         do_cmd(s, get_pdma_buf(s) + s->pdma_start);
248     }
249 }
250 
251 static void handle_satn(ESPState *s)
252 {
253     uint8_t buf[32];
254     int len;
255 
256     if (s->dma && !s->dma_enabled) {
257         s->dma_cb = handle_satn;
258         return;
259     }
260     s->pdma_cb = satn_pdma_cb;
261     len = get_cmd(s, buf, sizeof(buf));
262     if (len) {
263         do_cmd(s, buf);
264     }
265 }
266 
267 static void s_without_satn_pdma_cb(ESPState *s)
268 {
269     if (get_cmd_cb(s) < 0) {
270         return;
271     }
272     if (s->pdma_cur != s->pdma_start) {
273         do_busid_cmd(s, get_pdma_buf(s) + s->pdma_start, 0);
274     }
275 }
276 
277 static void handle_s_without_atn(ESPState *s)
278 {
279     uint8_t buf[32];
280     int len;
281 
282     if (s->dma && !s->dma_enabled) {
283         s->dma_cb = handle_s_without_atn;
284         return;
285     }
286     s->pdma_cb = s_without_satn_pdma_cb;
287     len = get_cmd(s, buf, sizeof(buf));
288     if (len) {
289         do_busid_cmd(s, buf, 0);
290     }
291 }
292 
293 static void satn_stop_pdma_cb(ESPState *s)
294 {
295     if (get_cmd_cb(s) < 0) {
296         return;
297     }
298     s->cmdlen = s->pdma_cur - s->pdma_start;
299     if (s->cmdlen) {
300         trace_esp_handle_satn_stop(s->cmdlen);
301         s->do_cmd = 1;
302         s->rregs[ESP_RSTAT] = STAT_TC | STAT_CD;
303         s->rregs[ESP_RINTR] = INTR_BS | INTR_FC;
304         s->rregs[ESP_RSEQ] = SEQ_CD;
305         esp_raise_irq(s);
306     }
307 }
308 
309 static void handle_satn_stop(ESPState *s)
310 {
311     if (s->dma && !s->dma_enabled) {
312         s->dma_cb = handle_satn_stop;
313         return;
314     }
315     s->pdma_cb = satn_stop_pdma_cb;
316     s->cmdlen = get_cmd(s, s->cmdbuf, sizeof(s->cmdbuf));
317     if (s->cmdlen) {
318         trace_esp_handle_satn_stop(s->cmdlen);
319         s->do_cmd = 1;
320         s->rregs[ESP_RSTAT] = STAT_TC | STAT_CD;
321         s->rregs[ESP_RINTR] = INTR_BS | INTR_FC;
322         s->rregs[ESP_RSEQ] = SEQ_CD;
323         esp_raise_irq(s);
324     }
325 }
326 
327 static void write_response_pdma_cb(ESPState *s)
328 {
329     s->rregs[ESP_RSTAT] = STAT_TC | STAT_ST;
330     s->rregs[ESP_RINTR] = INTR_BS | INTR_FC;
331     s->rregs[ESP_RSEQ] = SEQ_CD;
332     esp_raise_irq(s);
333 }
334 
335 static void write_response(ESPState *s)
336 {
337     trace_esp_write_response(s->status);
338     s->ti_buf[0] = s->status;
339     s->ti_buf[1] = 0;
340     if (s->dma) {
341         if (s->dma_memory_write) {
342             s->dma_memory_write(s->dma_opaque, s->ti_buf, 2);
343             s->rregs[ESP_RSTAT] = STAT_TC | STAT_ST;
344             s->rregs[ESP_RINTR] = INTR_BS | INTR_FC;
345             s->rregs[ESP_RSEQ] = SEQ_CD;
346         } else {
347             set_pdma(s, TI, 0, 2);
348             s->pdma_cb = write_response_pdma_cb;
349             esp_raise_drq(s);
350             return;
351         }
352     } else {
353         s->ti_size = 2;
354         s->ti_rptr = 0;
355         s->ti_wptr = 2;
356         s->rregs[ESP_RFLAGS] = 2;
357     }
358     esp_raise_irq(s);
359 }
360 
361 static void esp_dma_done(ESPState *s)
362 {
363     s->rregs[ESP_RSTAT] |= STAT_TC;
364     s->rregs[ESP_RINTR] = INTR_BS;
365     s->rregs[ESP_RSEQ] = 0;
366     s->rregs[ESP_RFLAGS] = 0;
367     esp_set_tc(s, 0);
368     esp_raise_irq(s);
369 }
370 
371 static void do_dma_pdma_cb(ESPState *s)
372 {
373     int to_device = ((s->rregs[ESP_RSTAT] & 7) == STAT_DO);
374     int len = s->pdma_cur - s->pdma_start;
375     if (s->do_cmd) {
376         s->ti_size = 0;
377         s->cmdlen = 0;
378         s->do_cmd = 0;
379         do_cmd(s, s->cmdbuf);
380         return;
381     }
382     s->dma_left -= len;
383     s->async_buf += len;
384     s->async_len -= len;
385     if (to_device) {
386         s->ti_size += len;
387     } else {
388         s->ti_size -= len;
389     }
390     if (s->async_len == 0) {
391         scsi_req_continue(s->current_req);
392         /*
393          * If there is still data to be read from the device then
394          * complete the DMA operation immediately.  Otherwise defer
395          * until the scsi layer has completed.
396          */
397         if (to_device || s->dma_left != 0 || s->ti_size == 0) {
398             return;
399         }
400     }
401 
402     /* Partially filled a scsi buffer. Complete immediately.  */
403     esp_dma_done(s);
404 }
405 
406 static void esp_do_dma(ESPState *s)
407 {
408     uint32_t len;
409     int to_device = ((s->rregs[ESP_RSTAT] & 7) == STAT_DO);
410 
411     len = s->dma_left;
412     if (s->do_cmd) {
413         /*
414          * handle_ti_cmd() case: esp_do_dma() is called only from
415          * handle_ti_cmd() with do_cmd != NULL (see the assert())
416          */
417         trace_esp_do_dma(s->cmdlen, len);
418         assert(s->cmdlen <= sizeof(s->cmdbuf) &&
419                len <= sizeof(s->cmdbuf) - s->cmdlen);
420         if (s->dma_memory_read) {
421             s->dma_memory_read(s->dma_opaque, &s->cmdbuf[s->cmdlen], len);
422         } else {
423             set_pdma(s, CMD, s->cmdlen, len);
424             s->pdma_cb = do_dma_pdma_cb;
425             esp_raise_drq(s);
426             return;
427         }
428         trace_esp_handle_ti_cmd(s->cmdlen);
429         s->ti_size = 0;
430         s->cmdlen = 0;
431         s->do_cmd = 0;
432         do_cmd(s, s->cmdbuf);
433         return;
434     }
435     if (s->async_len == 0) {
436         /* Defer until data is available.  */
437         return;
438     }
439     if (len > s->async_len) {
440         len = s->async_len;
441     }
442     if (to_device) {
443         if (s->dma_memory_read) {
444             s->dma_memory_read(s->dma_opaque, s->async_buf, len);
445         } else {
446             set_pdma(s, ASYNC, 0, len);
447             s->pdma_cb = do_dma_pdma_cb;
448             esp_raise_drq(s);
449             return;
450         }
451     } else {
452         if (s->dma_memory_write) {
453             s->dma_memory_write(s->dma_opaque, s->async_buf, len);
454         } else {
455             set_pdma(s, ASYNC, 0, len);
456             s->pdma_cb = do_dma_pdma_cb;
457             esp_raise_drq(s);
458             return;
459         }
460     }
461     s->dma_left -= len;
462     s->async_buf += len;
463     s->async_len -= len;
464     if (to_device) {
465         s->ti_size += len;
466     } else {
467         s->ti_size -= len;
468     }
469     if (s->async_len == 0) {
470         scsi_req_continue(s->current_req);
471         /*
472          * If there is still data to be read from the device then
473          * complete the DMA operation immediately.  Otherwise defer
474          * until the scsi layer has completed.
475          */
476         if (to_device || s->dma_left != 0 || s->ti_size == 0) {
477             return;
478         }
479     }
480 
481     /* Partially filled a scsi buffer. Complete immediately.  */
482     esp_dma_done(s);
483 }
484 
485 static void esp_report_command_complete(ESPState *s, uint32_t status)
486 {
487     trace_esp_command_complete();
488     if (s->ti_size != 0) {
489         trace_esp_command_complete_unexpected();
490     }
491     s->ti_size = 0;
492     s->dma_left = 0;
493     s->async_len = 0;
494     if (status) {
495         trace_esp_command_complete_fail();
496     }
497     s->status = status;
498     s->rregs[ESP_RSTAT] = STAT_ST;
499     esp_dma_done(s);
500     if (s->current_req) {
501         scsi_req_unref(s->current_req);
502         s->current_req = NULL;
503         s->current_dev = NULL;
504     }
505 }
506 
507 void esp_command_complete(SCSIRequest *req, size_t resid)
508 {
509     ESPState *s = req->hba_private;
510 
511     if (s->rregs[ESP_RSTAT] & STAT_INT) {
512         /*
513          * Defer handling command complete until the previous
514          * interrupt has been handled.
515          */
516         trace_esp_command_complete_deferred();
517         s->deferred_status = req->status;
518         s->deferred_complete = true;
519         return;
520     }
521     esp_report_command_complete(s, req->status);
522 }
523 
524 void esp_transfer_data(SCSIRequest *req, uint32_t len)
525 {
526     ESPState *s = req->hba_private;
527 
528     assert(!s->do_cmd);
529     trace_esp_transfer_data(s->dma_left, s->ti_size);
530     s->async_len = len;
531     s->async_buf = scsi_req_get_buf(req);
532     if (s->dma_left) {
533         esp_do_dma(s);
534     } else if (s->dma_counter != 0 && s->ti_size <= 0) {
535         /*
536          * If this was the last part of a DMA transfer then the
537          * completion interrupt is deferred to here.
538          */
539         esp_dma_done(s);
540     }
541 }
542 
543 static void handle_ti(ESPState *s)
544 {
545     uint32_t dmalen, minlen;
546 
547     if (s->dma && !s->dma_enabled) {
548         s->dma_cb = handle_ti;
549         return;
550     }
551 
552     dmalen = esp_get_tc(s);
553     if (dmalen == 0) {
554         dmalen = 0x10000;
555     }
556     s->dma_counter = dmalen;
557 
558     if (s->do_cmd) {
559         minlen = (dmalen < ESP_CMDBUF_SZ) ? dmalen : ESP_CMDBUF_SZ;
560     } else if (s->ti_size < 0) {
561         minlen = (dmalen < -s->ti_size) ? dmalen : -s->ti_size;
562     } else {
563         minlen = (dmalen < s->ti_size) ? dmalen : s->ti_size;
564     }
565     trace_esp_handle_ti(minlen);
566     if (s->dma) {
567         s->dma_left = minlen;
568         s->rregs[ESP_RSTAT] &= ~STAT_TC;
569         esp_do_dma(s);
570     } else if (s->do_cmd) {
571         trace_esp_handle_ti_cmd(s->cmdlen);
572         s->ti_size = 0;
573         s->cmdlen = 0;
574         s->do_cmd = 0;
575         do_cmd(s, s->cmdbuf);
576     }
577 }
578 
579 void esp_hard_reset(ESPState *s)
580 {
581     memset(s->rregs, 0, ESP_REGS);
582     memset(s->wregs, 0, ESP_REGS);
583     s->tchi_written = 0;
584     s->ti_size = 0;
585     s->ti_rptr = 0;
586     s->ti_wptr = 0;
587     s->dma = 0;
588     s->do_cmd = 0;
589     s->dma_cb = NULL;
590 
591     s->rregs[ESP_CFG1] = 7;
592 }
593 
594 static void esp_soft_reset(ESPState *s)
595 {
596     qemu_irq_lower(s->irq);
597     qemu_irq_lower(s->irq_data);
598     esp_hard_reset(s);
599 }
600 
601 static void parent_esp_reset(ESPState *s, int irq, int level)
602 {
603     if (level) {
604         esp_soft_reset(s);
605     }
606 }
607 
608 uint64_t esp_reg_read(ESPState *s, uint32_t saddr)
609 {
610     uint32_t val;
611 
612     switch (saddr) {
613     case ESP_FIFO:
614         if ((s->rregs[ESP_RSTAT] & STAT_PIO_MASK) == 0) {
615             /* Data out.  */
616             qemu_log_mask(LOG_UNIMP, "esp: PIO data read not implemented\n");
617             s->rregs[ESP_FIFO] = 0;
618         } else if (s->ti_rptr < s->ti_wptr) {
619             s->ti_size--;
620             s->rregs[ESP_FIFO] = s->ti_buf[s->ti_rptr++];
621         }
622         if (s->ti_rptr == s->ti_wptr) {
623             s->ti_rptr = 0;
624             s->ti_wptr = 0;
625         }
626         val = s->rregs[ESP_FIFO];
627         break;
628     case ESP_RINTR:
629         /*
630          * Clear sequence step, interrupt register and all status bits
631          * except TC
632          */
633         val = s->rregs[ESP_RINTR];
634         s->rregs[ESP_RINTR] = 0;
635         s->rregs[ESP_RSTAT] &= ~STAT_TC;
636         s->rregs[ESP_RSEQ] = SEQ_CD;
637         esp_lower_irq(s);
638         if (s->deferred_complete) {
639             esp_report_command_complete(s, s->deferred_status);
640             s->deferred_complete = false;
641         }
642         break;
643     case ESP_TCHI:
644         /* Return the unique id if the value has never been written */
645         if (!s->tchi_written) {
646             val = s->chip_id;
647         } else {
648             val = s->rregs[saddr];
649         }
650         break;
651     default:
652         val = s->rregs[saddr];
653         break;
654     }
655 
656     trace_esp_mem_readb(saddr, val);
657     return val;
658 }
659 
660 void esp_reg_write(ESPState *s, uint32_t saddr, uint64_t val)
661 {
662     trace_esp_mem_writeb(saddr, s->wregs[saddr], val);
663     switch (saddr) {
664     case ESP_TCHI:
665         s->tchi_written = true;
666         /* fall through */
667     case ESP_TCLO:
668     case ESP_TCMID:
669         s->rregs[ESP_RSTAT] &= ~STAT_TC;
670         break;
671     case ESP_FIFO:
672         if (s->do_cmd) {
673             if (s->cmdlen < ESP_CMDBUF_SZ) {
674                 s->cmdbuf[s->cmdlen++] = val & 0xff;
675             } else {
676                 trace_esp_error_fifo_overrun();
677             }
678         } else if (s->ti_wptr == TI_BUFSZ - 1) {
679             trace_esp_error_fifo_overrun();
680         } else {
681             s->ti_size++;
682             s->ti_buf[s->ti_wptr++] = val & 0xff;
683         }
684         break;
685     case ESP_CMD:
686         s->rregs[saddr] = val;
687         if (val & CMD_DMA) {
688             s->dma = 1;
689             /* Reload DMA counter.  */
690             s->rregs[ESP_TCLO] = s->wregs[ESP_TCLO];
691             s->rregs[ESP_TCMID] = s->wregs[ESP_TCMID];
692             s->rregs[ESP_TCHI] = s->wregs[ESP_TCHI];
693         } else {
694             s->dma = 0;
695         }
696         switch (val & CMD_CMD) {
697         case CMD_NOP:
698             trace_esp_mem_writeb_cmd_nop(val);
699             break;
700         case CMD_FLUSH:
701             trace_esp_mem_writeb_cmd_flush(val);
702             /*s->ti_size = 0;*/
703             s->rregs[ESP_RINTR] = INTR_FC;
704             s->rregs[ESP_RSEQ] = 0;
705             s->rregs[ESP_RFLAGS] = 0;
706             break;
707         case CMD_RESET:
708             trace_esp_mem_writeb_cmd_reset(val);
709             esp_soft_reset(s);
710             break;
711         case CMD_BUSRESET:
712             trace_esp_mem_writeb_cmd_bus_reset(val);
713             s->rregs[ESP_RINTR] = INTR_RST;
714             if (!(s->wregs[ESP_CFG1] & CFG1_RESREPT)) {
715                 esp_raise_irq(s);
716             }
717             break;
718         case CMD_TI:
719             trace_esp_mem_writeb_cmd_ti(val);
720             handle_ti(s);
721             break;
722         case CMD_ICCS:
723             trace_esp_mem_writeb_cmd_iccs(val);
724             write_response(s);
725             s->rregs[ESP_RINTR] = INTR_FC;
726             s->rregs[ESP_RSTAT] |= STAT_MI;
727             break;
728         case CMD_MSGACC:
729             trace_esp_mem_writeb_cmd_msgacc(val);
730             s->rregs[ESP_RINTR] = INTR_DC;
731             s->rregs[ESP_RSEQ] = 0;
732             s->rregs[ESP_RFLAGS] = 0;
733             esp_raise_irq(s);
734             break;
735         case CMD_PAD:
736             trace_esp_mem_writeb_cmd_pad(val);
737             s->rregs[ESP_RSTAT] = STAT_TC;
738             s->rregs[ESP_RINTR] = INTR_FC;
739             s->rregs[ESP_RSEQ] = 0;
740             break;
741         case CMD_SATN:
742             trace_esp_mem_writeb_cmd_satn(val);
743             break;
744         case CMD_RSTATN:
745             trace_esp_mem_writeb_cmd_rstatn(val);
746             break;
747         case CMD_SEL:
748             trace_esp_mem_writeb_cmd_sel(val);
749             handle_s_without_atn(s);
750             break;
751         case CMD_SELATN:
752             trace_esp_mem_writeb_cmd_selatn(val);
753             handle_satn(s);
754             break;
755         case CMD_SELATNS:
756             trace_esp_mem_writeb_cmd_selatns(val);
757             handle_satn_stop(s);
758             break;
759         case CMD_ENSEL:
760             trace_esp_mem_writeb_cmd_ensel(val);
761             s->rregs[ESP_RINTR] = 0;
762             break;
763         case CMD_DISSEL:
764             trace_esp_mem_writeb_cmd_dissel(val);
765             s->rregs[ESP_RINTR] = 0;
766             esp_raise_irq(s);
767             break;
768         default:
769             trace_esp_error_unhandled_command(val);
770             break;
771         }
772         break;
773     case ESP_WBUSID ... ESP_WSYNO:
774         break;
775     case ESP_CFG1:
776     case ESP_CFG2: case ESP_CFG3:
777     case ESP_RES3: case ESP_RES4:
778         s->rregs[saddr] = val;
779         break;
780     case ESP_WCCF ... ESP_WTEST:
781         break;
782     default:
783         trace_esp_error_invalid_write(val, saddr);
784         return;
785     }
786     s->wregs[saddr] = val;
787 }
788 
789 static bool esp_mem_accepts(void *opaque, hwaddr addr,
790                             unsigned size, bool is_write,
791                             MemTxAttrs attrs)
792 {
793     return (size == 1) || (is_write && size == 4);
794 }
795 
796 static bool esp_pdma_needed(void *opaque)
797 {
798     ESPState *s = opaque;
799     return s->dma_memory_read == NULL && s->dma_memory_write == NULL &&
800            s->dma_enabled;
801 }
802 
803 static const VMStateDescription vmstate_esp_pdma = {
804     .name = "esp/pdma",
805     .version_id = 1,
806     .minimum_version_id = 1,
807     .needed = esp_pdma_needed,
808     .fields = (VMStateField[]) {
809         VMSTATE_BUFFER(pdma_buf, ESPState),
810         VMSTATE_INT32(pdma_origin, ESPState),
811         VMSTATE_UINT32(pdma_len, ESPState),
812         VMSTATE_UINT32(pdma_start, ESPState),
813         VMSTATE_UINT32(pdma_cur, ESPState),
814         VMSTATE_END_OF_LIST()
815     }
816 };
817 
818 static int esp_pre_save(void *opaque)
819 {
820     ESPState *s = ESP(opaque);
821 
822     s->mig_version_id = vmstate_esp.version_id;
823     return 0;
824 }
825 
826 static int esp_post_load(void *opaque, int version_id)
827 {
828     ESPState *s = ESP(opaque);
829 
830     s->mig_version_id = vmstate_esp.version_id;
831     return 0;
832 }
833 
834 const VMStateDescription vmstate_esp = {
835     .name = "esp",
836     .version_id = 5,
837     .minimum_version_id = 3,
838     .pre_save = esp_pre_save,
839     .post_load = esp_post_load,
840     .fields = (VMStateField[]) {
841         VMSTATE_BUFFER(rregs, ESPState),
842         VMSTATE_BUFFER(wregs, ESPState),
843         VMSTATE_INT32(ti_size, ESPState),
844         VMSTATE_UINT32(ti_rptr, ESPState),
845         VMSTATE_UINT32(ti_wptr, ESPState),
846         VMSTATE_BUFFER(ti_buf, ESPState),
847         VMSTATE_UINT32(status, ESPState),
848         VMSTATE_UINT32(deferred_status, ESPState),
849         VMSTATE_BOOL(deferred_complete, ESPState),
850         VMSTATE_UINT32(dma, ESPState),
851         VMSTATE_PARTIAL_BUFFER(cmdbuf, ESPState, 16),
852         VMSTATE_BUFFER_START_MIDDLE_V(cmdbuf, ESPState, 16, 4),
853         VMSTATE_UINT32(cmdlen, ESPState),
854         VMSTATE_UINT32(do_cmd, ESPState),
855         VMSTATE_UINT32(dma_left, ESPState),
856         VMSTATE_END_OF_LIST()
857     },
858     .subsections = (const VMStateDescription * []) {
859         &vmstate_esp_pdma,
860         NULL
861     }
862 };
863 
864 static void sysbus_esp_mem_write(void *opaque, hwaddr addr,
865                                  uint64_t val, unsigned int size)
866 {
867     SysBusESPState *sysbus = opaque;
868     ESPState *s = ESP(&sysbus->esp);
869     uint32_t saddr;
870 
871     saddr = addr >> sysbus->it_shift;
872     esp_reg_write(s, saddr, val);
873 }
874 
875 static uint64_t sysbus_esp_mem_read(void *opaque, hwaddr addr,
876                                     unsigned int size)
877 {
878     SysBusESPState *sysbus = opaque;
879     ESPState *s = ESP(&sysbus->esp);
880     uint32_t saddr;
881 
882     saddr = addr >> sysbus->it_shift;
883     return esp_reg_read(s, saddr);
884 }
885 
886 static const MemoryRegionOps sysbus_esp_mem_ops = {
887     .read = sysbus_esp_mem_read,
888     .write = sysbus_esp_mem_write,
889     .endianness = DEVICE_NATIVE_ENDIAN,
890     .valid.accepts = esp_mem_accepts,
891 };
892 
893 static void sysbus_esp_pdma_write(void *opaque, hwaddr addr,
894                                   uint64_t val, unsigned int size)
895 {
896     SysBusESPState *sysbus = opaque;
897     ESPState *s = ESP(&sysbus->esp);
898     uint32_t dmalen;
899     uint8_t *buf = get_pdma_buf(s);
900 
901     trace_esp_pdma_write(size);
902 
903     dmalen = esp_get_tc(s);
904     if (dmalen == 0 || s->pdma_len == 0) {
905         return;
906     }
907     switch (size) {
908     case 1:
909         buf[s->pdma_cur++] = val;
910         s->pdma_len--;
911         dmalen--;
912         break;
913     case 2:
914         buf[s->pdma_cur++] = val >> 8;
915         buf[s->pdma_cur++] = val;
916         s->pdma_len -= 2;
917         dmalen -= 2;
918         break;
919     }
920     esp_set_tc(s, dmalen);
921     if (s->pdma_len == 0 && s->pdma_cb) {
922         esp_lower_drq(s);
923         s->pdma_cb(s);
924         s->pdma_cb = NULL;
925     }
926 }
927 
928 static uint64_t sysbus_esp_pdma_read(void *opaque, hwaddr addr,
929                                      unsigned int size)
930 {
931     SysBusESPState *sysbus = opaque;
932     ESPState *s = ESP(&sysbus->esp);
933     uint8_t *buf = get_pdma_buf(s);
934     uint64_t val = 0;
935 
936     trace_esp_pdma_read(size);
937 
938     if (s->pdma_len == 0) {
939         return 0;
940     }
941     switch (size) {
942     case 1:
943         val = buf[s->pdma_cur++];
944         s->pdma_len--;
945         break;
946     case 2:
947         val = buf[s->pdma_cur++];
948         val = (val << 8) | buf[s->pdma_cur++];
949         s->pdma_len -= 2;
950         break;
951     }
952 
953     if (s->pdma_len == 0 && s->pdma_cb) {
954         esp_lower_drq(s);
955         s->pdma_cb(s);
956         s->pdma_cb = NULL;
957     }
958     return val;
959 }
960 
961 static const MemoryRegionOps sysbus_esp_pdma_ops = {
962     .read = sysbus_esp_pdma_read,
963     .write = sysbus_esp_pdma_write,
964     .endianness = DEVICE_NATIVE_ENDIAN,
965     .valid.min_access_size = 1,
966     .valid.max_access_size = 2,
967 };
968 
969 static const struct SCSIBusInfo esp_scsi_info = {
970     .tcq = false,
971     .max_target = ESP_MAX_DEVS,
972     .max_lun = 7,
973 
974     .transfer_data = esp_transfer_data,
975     .complete = esp_command_complete,
976     .cancel = esp_request_cancelled
977 };
978 
979 static void sysbus_esp_gpio_demux(void *opaque, int irq, int level)
980 {
981     SysBusESPState *sysbus = SYSBUS_ESP(opaque);
982     ESPState *s = ESP(&sysbus->esp);
983 
984     switch (irq) {
985     case 0:
986         parent_esp_reset(s, irq, level);
987         break;
988     case 1:
989         esp_dma_enable(opaque, irq, level);
990         break;
991     }
992 }
993 
994 static void sysbus_esp_realize(DeviceState *dev, Error **errp)
995 {
996     SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
997     SysBusESPState *sysbus = SYSBUS_ESP(dev);
998     ESPState *s = ESP(&sysbus->esp);
999 
1000     if (!qdev_realize(DEVICE(s), NULL, errp)) {
1001         return;
1002     }
1003 
1004     sysbus_init_irq(sbd, &s->irq);
1005     sysbus_init_irq(sbd, &s->irq_data);
1006     assert(sysbus->it_shift != -1);
1007 
1008     s->chip_id = TCHI_FAS100A;
1009     memory_region_init_io(&sysbus->iomem, OBJECT(sysbus), &sysbus_esp_mem_ops,
1010                           sysbus, "esp-regs", ESP_REGS << sysbus->it_shift);
1011     sysbus_init_mmio(sbd, &sysbus->iomem);
1012     memory_region_init_io(&sysbus->pdma, OBJECT(sysbus), &sysbus_esp_pdma_ops,
1013                           sysbus, "esp-pdma", 2);
1014     sysbus_init_mmio(sbd, &sysbus->pdma);
1015 
1016     qdev_init_gpio_in(dev, sysbus_esp_gpio_demux, 2);
1017 
1018     scsi_bus_new(&s->bus, sizeof(s->bus), dev, &esp_scsi_info, NULL);
1019 }
1020 
1021 static void sysbus_esp_hard_reset(DeviceState *dev)
1022 {
1023     SysBusESPState *sysbus = SYSBUS_ESP(dev);
1024     ESPState *s = ESP(&sysbus->esp);
1025 
1026     esp_hard_reset(s);
1027 }
1028 
1029 static void sysbus_esp_init(Object *obj)
1030 {
1031     SysBusESPState *sysbus = SYSBUS_ESP(obj);
1032 
1033     object_initialize_child(obj, "esp", &sysbus->esp, TYPE_ESP);
1034 }
1035 
1036 static const VMStateDescription vmstate_sysbus_esp_scsi = {
1037     .name = "sysbusespscsi",
1038     .version_id = 2,
1039     .minimum_version_id = 1,
1040     .fields = (VMStateField[]) {
1041         VMSTATE_UINT8_V(esp.mig_version_id, SysBusESPState, 2),
1042         VMSTATE_STRUCT(esp, SysBusESPState, 0, vmstate_esp, ESPState),
1043         VMSTATE_END_OF_LIST()
1044     }
1045 };
1046 
1047 static void sysbus_esp_class_init(ObjectClass *klass, void *data)
1048 {
1049     DeviceClass *dc = DEVICE_CLASS(klass);
1050 
1051     dc->realize = sysbus_esp_realize;
1052     dc->reset = sysbus_esp_hard_reset;
1053     dc->vmsd = &vmstate_sysbus_esp_scsi;
1054     set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
1055 }
1056 
1057 static const TypeInfo sysbus_esp_info = {
1058     .name          = TYPE_SYSBUS_ESP,
1059     .parent        = TYPE_SYS_BUS_DEVICE,
1060     .instance_init = sysbus_esp_init,
1061     .instance_size = sizeof(SysBusESPState),
1062     .class_init    = sysbus_esp_class_init,
1063 };
1064 
1065 static void esp_class_init(ObjectClass *klass, void *data)
1066 {
1067     DeviceClass *dc = DEVICE_CLASS(klass);
1068 
1069     /* internal device for sysbusesp/pciespscsi, not user-creatable */
1070     dc->user_creatable = false;
1071     set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
1072 }
1073 
1074 static const TypeInfo esp_info = {
1075     .name = TYPE_ESP,
1076     .parent = TYPE_DEVICE,
1077     .instance_size = sizeof(ESPState),
1078     .class_init = esp_class_init,
1079 };
1080 
1081 static void esp_register_types(void)
1082 {
1083     type_register_static(&sysbus_esp_info);
1084     type_register_static(&esp_info);
1085 }
1086 
1087 type_init(esp_register_types)
1088