xref: /qemu/hw/scsi/esp.c (revision c04ed569b014126927760e4607385719bd66bff9)
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 uint32_t esp_get_stc(ESPState *s)
120 {
121     uint32_t dmalen;
122 
123     dmalen = s->wregs[ESP_TCLO];
124     dmalen |= s->wregs[ESP_TCMID] << 8;
125     dmalen |= s->wregs[ESP_TCHI] << 16;
126 
127     return dmalen;
128 }
129 
130 static void set_pdma(ESPState *s, enum pdma_origin_id origin,
131                      uint32_t index, uint32_t len)
132 {
133     s->pdma_origin = origin;
134     s->pdma_start = index;
135     s->pdma_cur = index;
136     s->pdma_len = len;
137 }
138 
139 static uint8_t *get_pdma_buf(ESPState *s)
140 {
141     switch (s->pdma_origin) {
142     case PDMA:
143         return s->pdma_buf;
144     case TI:
145         return s->ti_buf;
146     case CMD:
147         return s->cmdbuf;
148     case ASYNC:
149         return s->async_buf;
150     }
151     return NULL;
152 }
153 
154 static int get_cmd_cb(ESPState *s)
155 {
156     int target;
157 
158     target = s->wregs[ESP_WBUSID] & BUSID_DID;
159 
160     s->ti_size = 0;
161     s->ti_rptr = 0;
162     s->ti_wptr = 0;
163 
164     if (s->current_req) {
165         /* Started a new command before the old one finished.  Cancel it.  */
166         scsi_req_cancel(s->current_req);
167         s->async_len = 0;
168     }
169 
170     s->current_dev = scsi_device_find(&s->bus, 0, target, 0);
171     if (!s->current_dev) {
172         /* No such drive */
173         s->rregs[ESP_RSTAT] = 0;
174         s->rregs[ESP_RINTR] = INTR_DC;
175         s->rregs[ESP_RSEQ] = SEQ_0;
176         esp_raise_irq(s);
177         return -1;
178     }
179     return 0;
180 }
181 
182 static uint32_t get_cmd(ESPState *s, uint8_t *buf, uint8_t buflen)
183 {
184     uint32_t dmalen;
185     int target;
186 
187     target = s->wregs[ESP_WBUSID] & BUSID_DID;
188     if (s->dma) {
189         dmalen = esp_get_tc(s);
190         if (dmalen > buflen) {
191             return 0;
192         }
193         if (s->dma_memory_read) {
194             s->dma_memory_read(s->dma_opaque, buf, dmalen);
195         } else {
196             memcpy(s->pdma_buf, buf, dmalen);
197             set_pdma(s, PDMA, 0, dmalen);
198             esp_raise_drq(s);
199             return 0;
200         }
201     } else {
202         dmalen = s->ti_size;
203         if (dmalen > TI_BUFSZ) {
204             return 0;
205         }
206         memcpy(buf, s->ti_buf, dmalen);
207         buf[0] = buf[2] >> 5;
208     }
209     trace_esp_get_cmd(dmalen, target);
210 
211     if (get_cmd_cb(s) < 0) {
212         return 0;
213     }
214     return dmalen;
215 }
216 
217 static void do_busid_cmd(ESPState *s, uint8_t *buf, uint8_t busid)
218 {
219     int32_t datalen;
220     int lun;
221     SCSIDevice *current_lun;
222 
223     trace_esp_do_busid_cmd(busid);
224     lun = busid & 7;
225     current_lun = scsi_device_find(&s->bus, 0, s->current_dev->id, lun);
226     s->current_req = scsi_req_new(current_lun, 0, lun, buf, s);
227     datalen = scsi_req_enqueue(s->current_req);
228     s->ti_size = datalen;
229     if (datalen != 0) {
230         s->rregs[ESP_RSTAT] = STAT_TC;
231         s->dma_left = 0;
232         s->dma_counter = 0;
233         if (datalen > 0) {
234             s->rregs[ESP_RSTAT] |= STAT_DI;
235         } else {
236             s->rregs[ESP_RSTAT] |= STAT_DO;
237         }
238         scsi_req_continue(s->current_req);
239     }
240     s->rregs[ESP_RINTR] = INTR_BS | INTR_FC;
241     s->rregs[ESP_RSEQ] = SEQ_CD;
242     esp_raise_irq(s);
243 }
244 
245 static void do_cmd(ESPState *s, uint8_t *buf)
246 {
247     uint8_t busid = buf[0];
248 
249     do_busid_cmd(s, &buf[1], busid);
250 }
251 
252 static void satn_pdma_cb(ESPState *s)
253 {
254     if (get_cmd_cb(s) < 0) {
255         return;
256     }
257     if (s->pdma_cur != s->pdma_start) {
258         do_cmd(s, get_pdma_buf(s) + s->pdma_start);
259     }
260 }
261 
262 static void handle_satn(ESPState *s)
263 {
264     uint8_t buf[32];
265     int len;
266 
267     if (s->dma && !s->dma_enabled) {
268         s->dma_cb = handle_satn;
269         return;
270     }
271     s->pdma_cb = satn_pdma_cb;
272     len = get_cmd(s, buf, sizeof(buf));
273     if (len) {
274         do_cmd(s, buf);
275     }
276 }
277 
278 static void s_without_satn_pdma_cb(ESPState *s)
279 {
280     if (get_cmd_cb(s) < 0) {
281         return;
282     }
283     if (s->pdma_cur != s->pdma_start) {
284         do_busid_cmd(s, get_pdma_buf(s) + s->pdma_start, 0);
285     }
286 }
287 
288 static void handle_s_without_atn(ESPState *s)
289 {
290     uint8_t buf[32];
291     int len;
292 
293     if (s->dma && !s->dma_enabled) {
294         s->dma_cb = handle_s_without_atn;
295         return;
296     }
297     s->pdma_cb = s_without_satn_pdma_cb;
298     len = get_cmd(s, buf, sizeof(buf));
299     if (len) {
300         do_busid_cmd(s, buf, 0);
301     }
302 }
303 
304 static void satn_stop_pdma_cb(ESPState *s)
305 {
306     if (get_cmd_cb(s) < 0) {
307         return;
308     }
309     s->cmdlen = s->pdma_cur - s->pdma_start;
310     if (s->cmdlen) {
311         trace_esp_handle_satn_stop(s->cmdlen);
312         s->do_cmd = 1;
313         s->rregs[ESP_RSTAT] = STAT_TC | STAT_CD;
314         s->rregs[ESP_RINTR] = INTR_BS | INTR_FC;
315         s->rregs[ESP_RSEQ] = SEQ_CD;
316         esp_raise_irq(s);
317     }
318 }
319 
320 static void handle_satn_stop(ESPState *s)
321 {
322     if (s->dma && !s->dma_enabled) {
323         s->dma_cb = handle_satn_stop;
324         return;
325     }
326     s->pdma_cb = satn_stop_pdma_cb;
327     s->cmdlen = get_cmd(s, s->cmdbuf, sizeof(s->cmdbuf));
328     if (s->cmdlen) {
329         trace_esp_handle_satn_stop(s->cmdlen);
330         s->do_cmd = 1;
331         s->rregs[ESP_RSTAT] = STAT_TC | STAT_CD;
332         s->rregs[ESP_RINTR] = INTR_BS | INTR_FC;
333         s->rregs[ESP_RSEQ] = SEQ_CD;
334         esp_raise_irq(s);
335     }
336 }
337 
338 static void write_response_pdma_cb(ESPState *s)
339 {
340     s->rregs[ESP_RSTAT] = STAT_TC | STAT_ST;
341     s->rregs[ESP_RINTR] = INTR_BS | INTR_FC;
342     s->rregs[ESP_RSEQ] = SEQ_CD;
343     esp_raise_irq(s);
344 }
345 
346 static void write_response(ESPState *s)
347 {
348     trace_esp_write_response(s->status);
349     s->ti_buf[0] = s->status;
350     s->ti_buf[1] = 0;
351     if (s->dma) {
352         if (s->dma_memory_write) {
353             s->dma_memory_write(s->dma_opaque, s->ti_buf, 2);
354             s->rregs[ESP_RSTAT] = STAT_TC | STAT_ST;
355             s->rregs[ESP_RINTR] = INTR_BS | INTR_FC;
356             s->rregs[ESP_RSEQ] = SEQ_CD;
357         } else {
358             set_pdma(s, TI, 0, 2);
359             s->pdma_cb = write_response_pdma_cb;
360             esp_raise_drq(s);
361             return;
362         }
363     } else {
364         s->ti_size = 2;
365         s->ti_rptr = 0;
366         s->ti_wptr = 2;
367         s->rregs[ESP_RFLAGS] = 2;
368     }
369     esp_raise_irq(s);
370 }
371 
372 static void esp_dma_done(ESPState *s)
373 {
374     s->rregs[ESP_RSTAT] |= STAT_TC;
375     s->rregs[ESP_RINTR] = INTR_BS;
376     s->rregs[ESP_RSEQ] = 0;
377     s->rregs[ESP_RFLAGS] = 0;
378     esp_set_tc(s, 0);
379     esp_raise_irq(s);
380 }
381 
382 static void do_dma_pdma_cb(ESPState *s)
383 {
384     int to_device = ((s->rregs[ESP_RSTAT] & 7) == STAT_DO);
385     int len = s->pdma_cur - s->pdma_start;
386     if (s->do_cmd) {
387         s->ti_size = 0;
388         s->cmdlen = 0;
389         s->do_cmd = 0;
390         do_cmd(s, s->cmdbuf);
391         return;
392     }
393     s->dma_left -= len;
394     s->async_buf += len;
395     s->async_len -= len;
396     if (to_device) {
397         s->ti_size += len;
398     } else {
399         s->ti_size -= len;
400     }
401     if (s->async_len == 0) {
402         scsi_req_continue(s->current_req);
403         /*
404          * If there is still data to be read from the device then
405          * complete the DMA operation immediately.  Otherwise defer
406          * until the scsi layer has completed.
407          */
408         if (to_device || s->dma_left != 0 || s->ti_size == 0) {
409             return;
410         }
411     }
412 
413     /* Partially filled a scsi buffer. Complete immediately.  */
414     esp_dma_done(s);
415 }
416 
417 static void esp_do_dma(ESPState *s)
418 {
419     uint32_t len;
420     int to_device = ((s->rregs[ESP_RSTAT] & 7) == STAT_DO);
421 
422     len = s->dma_left;
423     if (s->do_cmd) {
424         /*
425          * handle_ti_cmd() case: esp_do_dma() is called only from
426          * handle_ti_cmd() with do_cmd != NULL (see the assert())
427          */
428         trace_esp_do_dma(s->cmdlen, len);
429         assert(s->cmdlen <= sizeof(s->cmdbuf) &&
430                len <= sizeof(s->cmdbuf) - s->cmdlen);
431         if (s->dma_memory_read) {
432             s->dma_memory_read(s->dma_opaque, &s->cmdbuf[s->cmdlen], len);
433         } else {
434             set_pdma(s, CMD, s->cmdlen, len);
435             s->pdma_cb = do_dma_pdma_cb;
436             esp_raise_drq(s);
437             return;
438         }
439         trace_esp_handle_ti_cmd(s->cmdlen);
440         s->ti_size = 0;
441         s->cmdlen = 0;
442         s->do_cmd = 0;
443         do_cmd(s, s->cmdbuf);
444         return;
445     }
446     if (s->async_len == 0) {
447         /* Defer until data is available.  */
448         return;
449     }
450     if (len > s->async_len) {
451         len = s->async_len;
452     }
453     if (to_device) {
454         if (s->dma_memory_read) {
455             s->dma_memory_read(s->dma_opaque, s->async_buf, len);
456         } else {
457             set_pdma(s, ASYNC, 0, len);
458             s->pdma_cb = do_dma_pdma_cb;
459             esp_raise_drq(s);
460             return;
461         }
462     } else {
463         if (s->dma_memory_write) {
464             s->dma_memory_write(s->dma_opaque, s->async_buf, len);
465         } else {
466             set_pdma(s, ASYNC, 0, len);
467             s->pdma_cb = do_dma_pdma_cb;
468             esp_raise_drq(s);
469             return;
470         }
471     }
472     s->dma_left -= len;
473     s->async_buf += len;
474     s->async_len -= len;
475     if (to_device) {
476         s->ti_size += len;
477     } else {
478         s->ti_size -= len;
479     }
480     if (s->async_len == 0) {
481         scsi_req_continue(s->current_req);
482         /*
483          * If there is still data to be read from the device then
484          * complete the DMA operation immediately.  Otherwise defer
485          * until the scsi layer has completed.
486          */
487         if (to_device || s->dma_left != 0 || s->ti_size == 0) {
488             return;
489         }
490     }
491 
492     /* Partially filled a scsi buffer. Complete immediately.  */
493     esp_dma_done(s);
494 }
495 
496 static void esp_report_command_complete(ESPState *s, uint32_t status)
497 {
498     trace_esp_command_complete();
499     if (s->ti_size != 0) {
500         trace_esp_command_complete_unexpected();
501     }
502     s->ti_size = 0;
503     s->dma_left = 0;
504     s->async_len = 0;
505     if (status) {
506         trace_esp_command_complete_fail();
507     }
508     s->status = status;
509     s->rregs[ESP_RSTAT] = STAT_ST;
510     esp_dma_done(s);
511     if (s->current_req) {
512         scsi_req_unref(s->current_req);
513         s->current_req = NULL;
514         s->current_dev = NULL;
515     }
516 }
517 
518 void esp_command_complete(SCSIRequest *req, size_t resid)
519 {
520     ESPState *s = req->hba_private;
521 
522     if (s->rregs[ESP_RSTAT] & STAT_INT) {
523         /*
524          * Defer handling command complete until the previous
525          * interrupt has been handled.
526          */
527         trace_esp_command_complete_deferred();
528         s->deferred_status = req->status;
529         s->deferred_complete = true;
530         return;
531     }
532     esp_report_command_complete(s, req->status);
533 }
534 
535 void esp_transfer_data(SCSIRequest *req, uint32_t len)
536 {
537     ESPState *s = req->hba_private;
538 
539     assert(!s->do_cmd);
540     trace_esp_transfer_data(s->dma_left, s->ti_size);
541     s->async_len = len;
542     s->async_buf = scsi_req_get_buf(req);
543     if (s->dma_left) {
544         esp_do_dma(s);
545     } else if (s->dma_counter != 0 && s->ti_size <= 0) {
546         /*
547          * If this was the last part of a DMA transfer then the
548          * completion interrupt is deferred to here.
549          */
550         esp_dma_done(s);
551     }
552 }
553 
554 static void handle_ti(ESPState *s)
555 {
556     uint32_t dmalen, minlen;
557 
558     if (s->dma && !s->dma_enabled) {
559         s->dma_cb = handle_ti;
560         return;
561     }
562 
563     dmalen = esp_get_tc(s);
564     if (dmalen == 0) {
565         dmalen = 0x10000;
566     }
567     s->dma_counter = dmalen;
568 
569     if (s->do_cmd) {
570         minlen = (dmalen < ESP_CMDBUF_SZ) ? dmalen : ESP_CMDBUF_SZ;
571     } else if (s->ti_size < 0) {
572         minlen = (dmalen < -s->ti_size) ? dmalen : -s->ti_size;
573     } else {
574         minlen = (dmalen < s->ti_size) ? dmalen : s->ti_size;
575     }
576     trace_esp_handle_ti(minlen);
577     if (s->dma) {
578         s->dma_left = minlen;
579         s->rregs[ESP_RSTAT] &= ~STAT_TC;
580         esp_do_dma(s);
581     } else if (s->do_cmd) {
582         trace_esp_handle_ti_cmd(s->cmdlen);
583         s->ti_size = 0;
584         s->cmdlen = 0;
585         s->do_cmd = 0;
586         do_cmd(s, s->cmdbuf);
587     }
588 }
589 
590 void esp_hard_reset(ESPState *s)
591 {
592     memset(s->rregs, 0, ESP_REGS);
593     memset(s->wregs, 0, ESP_REGS);
594     s->tchi_written = 0;
595     s->ti_size = 0;
596     s->ti_rptr = 0;
597     s->ti_wptr = 0;
598     s->dma = 0;
599     s->do_cmd = 0;
600     s->dma_cb = NULL;
601 
602     s->rregs[ESP_CFG1] = 7;
603 }
604 
605 static void esp_soft_reset(ESPState *s)
606 {
607     qemu_irq_lower(s->irq);
608     qemu_irq_lower(s->irq_data);
609     esp_hard_reset(s);
610 }
611 
612 static void parent_esp_reset(ESPState *s, int irq, int level)
613 {
614     if (level) {
615         esp_soft_reset(s);
616     }
617 }
618 
619 uint64_t esp_reg_read(ESPState *s, uint32_t saddr)
620 {
621     uint32_t val;
622 
623     switch (saddr) {
624     case ESP_FIFO:
625         if ((s->rregs[ESP_RSTAT] & STAT_PIO_MASK) == 0) {
626             /* Data out.  */
627             qemu_log_mask(LOG_UNIMP, "esp: PIO data read not implemented\n");
628             s->rregs[ESP_FIFO] = 0;
629         } else if (s->ti_rptr < s->ti_wptr) {
630             s->ti_size--;
631             s->rregs[ESP_FIFO] = s->ti_buf[s->ti_rptr++];
632         }
633         if (s->ti_rptr == s->ti_wptr) {
634             s->ti_rptr = 0;
635             s->ti_wptr = 0;
636         }
637         val = s->rregs[ESP_FIFO];
638         break;
639     case ESP_RINTR:
640         /*
641          * Clear sequence step, interrupt register and all status bits
642          * except TC
643          */
644         val = s->rregs[ESP_RINTR];
645         s->rregs[ESP_RINTR] = 0;
646         s->rregs[ESP_RSTAT] &= ~STAT_TC;
647         s->rregs[ESP_RSEQ] = SEQ_CD;
648         esp_lower_irq(s);
649         if (s->deferred_complete) {
650             esp_report_command_complete(s, s->deferred_status);
651             s->deferred_complete = false;
652         }
653         break;
654     case ESP_TCHI:
655         /* Return the unique id if the value has never been written */
656         if (!s->tchi_written) {
657             val = s->chip_id;
658         } else {
659             val = s->rregs[saddr];
660         }
661         break;
662     default:
663         val = s->rregs[saddr];
664         break;
665     }
666 
667     trace_esp_mem_readb(saddr, val);
668     return val;
669 }
670 
671 void esp_reg_write(ESPState *s, uint32_t saddr, uint64_t val)
672 {
673     trace_esp_mem_writeb(saddr, s->wregs[saddr], val);
674     switch (saddr) {
675     case ESP_TCHI:
676         s->tchi_written = true;
677         /* fall through */
678     case ESP_TCLO:
679     case ESP_TCMID:
680         s->rregs[ESP_RSTAT] &= ~STAT_TC;
681         break;
682     case ESP_FIFO:
683         if (s->do_cmd) {
684             if (s->cmdlen < ESP_CMDBUF_SZ) {
685                 s->cmdbuf[s->cmdlen++] = val & 0xff;
686             } else {
687                 trace_esp_error_fifo_overrun();
688             }
689         } else if (s->ti_wptr == TI_BUFSZ - 1) {
690             trace_esp_error_fifo_overrun();
691         } else {
692             s->ti_size++;
693             s->ti_buf[s->ti_wptr++] = val & 0xff;
694         }
695         break;
696     case ESP_CMD:
697         s->rregs[saddr] = val;
698         if (val & CMD_DMA) {
699             s->dma = 1;
700             /* Reload DMA counter.  */
701             esp_set_tc(s, esp_get_stc(s));
702         } else {
703             s->dma = 0;
704         }
705         switch (val & CMD_CMD) {
706         case CMD_NOP:
707             trace_esp_mem_writeb_cmd_nop(val);
708             break;
709         case CMD_FLUSH:
710             trace_esp_mem_writeb_cmd_flush(val);
711             /*s->ti_size = 0;*/
712             s->rregs[ESP_RINTR] = INTR_FC;
713             s->rregs[ESP_RSEQ] = 0;
714             s->rregs[ESP_RFLAGS] = 0;
715             break;
716         case CMD_RESET:
717             trace_esp_mem_writeb_cmd_reset(val);
718             esp_soft_reset(s);
719             break;
720         case CMD_BUSRESET:
721             trace_esp_mem_writeb_cmd_bus_reset(val);
722             s->rregs[ESP_RINTR] = INTR_RST;
723             if (!(s->wregs[ESP_CFG1] & CFG1_RESREPT)) {
724                 esp_raise_irq(s);
725             }
726             break;
727         case CMD_TI:
728             trace_esp_mem_writeb_cmd_ti(val);
729             handle_ti(s);
730             break;
731         case CMD_ICCS:
732             trace_esp_mem_writeb_cmd_iccs(val);
733             write_response(s);
734             s->rregs[ESP_RINTR] = INTR_FC;
735             s->rregs[ESP_RSTAT] |= STAT_MI;
736             break;
737         case CMD_MSGACC:
738             trace_esp_mem_writeb_cmd_msgacc(val);
739             s->rregs[ESP_RINTR] = INTR_DC;
740             s->rregs[ESP_RSEQ] = 0;
741             s->rregs[ESP_RFLAGS] = 0;
742             esp_raise_irq(s);
743             break;
744         case CMD_PAD:
745             trace_esp_mem_writeb_cmd_pad(val);
746             s->rregs[ESP_RSTAT] = STAT_TC;
747             s->rregs[ESP_RINTR] = INTR_FC;
748             s->rregs[ESP_RSEQ] = 0;
749             break;
750         case CMD_SATN:
751             trace_esp_mem_writeb_cmd_satn(val);
752             break;
753         case CMD_RSTATN:
754             trace_esp_mem_writeb_cmd_rstatn(val);
755             break;
756         case CMD_SEL:
757             trace_esp_mem_writeb_cmd_sel(val);
758             handle_s_without_atn(s);
759             break;
760         case CMD_SELATN:
761             trace_esp_mem_writeb_cmd_selatn(val);
762             handle_satn(s);
763             break;
764         case CMD_SELATNS:
765             trace_esp_mem_writeb_cmd_selatns(val);
766             handle_satn_stop(s);
767             break;
768         case CMD_ENSEL:
769             trace_esp_mem_writeb_cmd_ensel(val);
770             s->rregs[ESP_RINTR] = 0;
771             break;
772         case CMD_DISSEL:
773             trace_esp_mem_writeb_cmd_dissel(val);
774             s->rregs[ESP_RINTR] = 0;
775             esp_raise_irq(s);
776             break;
777         default:
778             trace_esp_error_unhandled_command(val);
779             break;
780         }
781         break;
782     case ESP_WBUSID ... ESP_WSYNO:
783         break;
784     case ESP_CFG1:
785     case ESP_CFG2: case ESP_CFG3:
786     case ESP_RES3: case ESP_RES4:
787         s->rregs[saddr] = val;
788         break;
789     case ESP_WCCF ... ESP_WTEST:
790         break;
791     default:
792         trace_esp_error_invalid_write(val, saddr);
793         return;
794     }
795     s->wregs[saddr] = val;
796 }
797 
798 static bool esp_mem_accepts(void *opaque, hwaddr addr,
799                             unsigned size, bool is_write,
800                             MemTxAttrs attrs)
801 {
802     return (size == 1) || (is_write && size == 4);
803 }
804 
805 static bool esp_pdma_needed(void *opaque)
806 {
807     ESPState *s = opaque;
808     return s->dma_memory_read == NULL && s->dma_memory_write == NULL &&
809            s->dma_enabled;
810 }
811 
812 static const VMStateDescription vmstate_esp_pdma = {
813     .name = "esp/pdma",
814     .version_id = 1,
815     .minimum_version_id = 1,
816     .needed = esp_pdma_needed,
817     .fields = (VMStateField[]) {
818         VMSTATE_BUFFER(pdma_buf, ESPState),
819         VMSTATE_INT32(pdma_origin, ESPState),
820         VMSTATE_UINT32(pdma_len, ESPState),
821         VMSTATE_UINT32(pdma_start, ESPState),
822         VMSTATE_UINT32(pdma_cur, ESPState),
823         VMSTATE_END_OF_LIST()
824     }
825 };
826 
827 static int esp_pre_save(void *opaque)
828 {
829     ESPState *s = ESP(opaque);
830 
831     s->mig_version_id = vmstate_esp.version_id;
832     return 0;
833 }
834 
835 static int esp_post_load(void *opaque, int version_id)
836 {
837     ESPState *s = ESP(opaque);
838 
839     s->mig_version_id = vmstate_esp.version_id;
840     return 0;
841 }
842 
843 const VMStateDescription vmstate_esp = {
844     .name = "esp",
845     .version_id = 5,
846     .minimum_version_id = 3,
847     .pre_save = esp_pre_save,
848     .post_load = esp_post_load,
849     .fields = (VMStateField[]) {
850         VMSTATE_BUFFER(rregs, ESPState),
851         VMSTATE_BUFFER(wregs, ESPState),
852         VMSTATE_INT32(ti_size, ESPState),
853         VMSTATE_UINT32(ti_rptr, ESPState),
854         VMSTATE_UINT32(ti_wptr, ESPState),
855         VMSTATE_BUFFER(ti_buf, ESPState),
856         VMSTATE_UINT32(status, ESPState),
857         VMSTATE_UINT32(deferred_status, ESPState),
858         VMSTATE_BOOL(deferred_complete, ESPState),
859         VMSTATE_UINT32(dma, ESPState),
860         VMSTATE_PARTIAL_BUFFER(cmdbuf, ESPState, 16),
861         VMSTATE_BUFFER_START_MIDDLE_V(cmdbuf, ESPState, 16, 4),
862         VMSTATE_UINT32(cmdlen, ESPState),
863         VMSTATE_UINT32(do_cmd, ESPState),
864         VMSTATE_UINT32(dma_left, ESPState),
865         VMSTATE_END_OF_LIST()
866     },
867     .subsections = (const VMStateDescription * []) {
868         &vmstate_esp_pdma,
869         NULL
870     }
871 };
872 
873 static void sysbus_esp_mem_write(void *opaque, hwaddr addr,
874                                  uint64_t val, unsigned int size)
875 {
876     SysBusESPState *sysbus = opaque;
877     ESPState *s = ESP(&sysbus->esp);
878     uint32_t saddr;
879 
880     saddr = addr >> sysbus->it_shift;
881     esp_reg_write(s, saddr, val);
882 }
883 
884 static uint64_t sysbus_esp_mem_read(void *opaque, hwaddr addr,
885                                     unsigned int size)
886 {
887     SysBusESPState *sysbus = opaque;
888     ESPState *s = ESP(&sysbus->esp);
889     uint32_t saddr;
890 
891     saddr = addr >> sysbus->it_shift;
892     return esp_reg_read(s, saddr);
893 }
894 
895 static const MemoryRegionOps sysbus_esp_mem_ops = {
896     .read = sysbus_esp_mem_read,
897     .write = sysbus_esp_mem_write,
898     .endianness = DEVICE_NATIVE_ENDIAN,
899     .valid.accepts = esp_mem_accepts,
900 };
901 
902 static void sysbus_esp_pdma_write(void *opaque, hwaddr addr,
903                                   uint64_t val, unsigned int size)
904 {
905     SysBusESPState *sysbus = opaque;
906     ESPState *s = ESP(&sysbus->esp);
907     uint32_t dmalen;
908     uint8_t *buf = get_pdma_buf(s);
909 
910     trace_esp_pdma_write(size);
911 
912     dmalen = esp_get_tc(s);
913     if (dmalen == 0 || s->pdma_len == 0) {
914         return;
915     }
916     switch (size) {
917     case 1:
918         buf[s->pdma_cur++] = val;
919         s->pdma_len--;
920         dmalen--;
921         break;
922     case 2:
923         buf[s->pdma_cur++] = val >> 8;
924         buf[s->pdma_cur++] = val;
925         s->pdma_len -= 2;
926         dmalen -= 2;
927         break;
928     }
929     esp_set_tc(s, dmalen);
930     if (s->pdma_len == 0 && s->pdma_cb) {
931         esp_lower_drq(s);
932         s->pdma_cb(s);
933         s->pdma_cb = NULL;
934     }
935 }
936 
937 static uint64_t sysbus_esp_pdma_read(void *opaque, hwaddr addr,
938                                      unsigned int size)
939 {
940     SysBusESPState *sysbus = opaque;
941     ESPState *s = ESP(&sysbus->esp);
942     uint8_t *buf = get_pdma_buf(s);
943     uint64_t val = 0;
944 
945     trace_esp_pdma_read(size);
946 
947     if (s->pdma_len == 0) {
948         return 0;
949     }
950     switch (size) {
951     case 1:
952         val = buf[s->pdma_cur++];
953         s->pdma_len--;
954         break;
955     case 2:
956         val = buf[s->pdma_cur++];
957         val = (val << 8) | buf[s->pdma_cur++];
958         s->pdma_len -= 2;
959         break;
960     }
961 
962     if (s->pdma_len == 0 && s->pdma_cb) {
963         esp_lower_drq(s);
964         s->pdma_cb(s);
965         s->pdma_cb = NULL;
966     }
967     return val;
968 }
969 
970 static const MemoryRegionOps sysbus_esp_pdma_ops = {
971     .read = sysbus_esp_pdma_read,
972     .write = sysbus_esp_pdma_write,
973     .endianness = DEVICE_NATIVE_ENDIAN,
974     .valid.min_access_size = 1,
975     .valid.max_access_size = 2,
976 };
977 
978 static const struct SCSIBusInfo esp_scsi_info = {
979     .tcq = false,
980     .max_target = ESP_MAX_DEVS,
981     .max_lun = 7,
982 
983     .transfer_data = esp_transfer_data,
984     .complete = esp_command_complete,
985     .cancel = esp_request_cancelled
986 };
987 
988 static void sysbus_esp_gpio_demux(void *opaque, int irq, int level)
989 {
990     SysBusESPState *sysbus = SYSBUS_ESP(opaque);
991     ESPState *s = ESP(&sysbus->esp);
992 
993     switch (irq) {
994     case 0:
995         parent_esp_reset(s, irq, level);
996         break;
997     case 1:
998         esp_dma_enable(opaque, irq, level);
999         break;
1000     }
1001 }
1002 
1003 static void sysbus_esp_realize(DeviceState *dev, Error **errp)
1004 {
1005     SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
1006     SysBusESPState *sysbus = SYSBUS_ESP(dev);
1007     ESPState *s = ESP(&sysbus->esp);
1008 
1009     if (!qdev_realize(DEVICE(s), NULL, errp)) {
1010         return;
1011     }
1012 
1013     sysbus_init_irq(sbd, &s->irq);
1014     sysbus_init_irq(sbd, &s->irq_data);
1015     assert(sysbus->it_shift != -1);
1016 
1017     s->chip_id = TCHI_FAS100A;
1018     memory_region_init_io(&sysbus->iomem, OBJECT(sysbus), &sysbus_esp_mem_ops,
1019                           sysbus, "esp-regs", ESP_REGS << sysbus->it_shift);
1020     sysbus_init_mmio(sbd, &sysbus->iomem);
1021     memory_region_init_io(&sysbus->pdma, OBJECT(sysbus), &sysbus_esp_pdma_ops,
1022                           sysbus, "esp-pdma", 2);
1023     sysbus_init_mmio(sbd, &sysbus->pdma);
1024 
1025     qdev_init_gpio_in(dev, sysbus_esp_gpio_demux, 2);
1026 
1027     scsi_bus_new(&s->bus, sizeof(s->bus), dev, &esp_scsi_info, NULL);
1028 }
1029 
1030 static void sysbus_esp_hard_reset(DeviceState *dev)
1031 {
1032     SysBusESPState *sysbus = SYSBUS_ESP(dev);
1033     ESPState *s = ESP(&sysbus->esp);
1034 
1035     esp_hard_reset(s);
1036 }
1037 
1038 static void sysbus_esp_init(Object *obj)
1039 {
1040     SysBusESPState *sysbus = SYSBUS_ESP(obj);
1041 
1042     object_initialize_child(obj, "esp", &sysbus->esp, TYPE_ESP);
1043 }
1044 
1045 static const VMStateDescription vmstate_sysbus_esp_scsi = {
1046     .name = "sysbusespscsi",
1047     .version_id = 2,
1048     .minimum_version_id = 1,
1049     .fields = (VMStateField[]) {
1050         VMSTATE_UINT8_V(esp.mig_version_id, SysBusESPState, 2),
1051         VMSTATE_STRUCT(esp, SysBusESPState, 0, vmstate_esp, ESPState),
1052         VMSTATE_END_OF_LIST()
1053     }
1054 };
1055 
1056 static void sysbus_esp_class_init(ObjectClass *klass, void *data)
1057 {
1058     DeviceClass *dc = DEVICE_CLASS(klass);
1059 
1060     dc->realize = sysbus_esp_realize;
1061     dc->reset = sysbus_esp_hard_reset;
1062     dc->vmsd = &vmstate_sysbus_esp_scsi;
1063     set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
1064 }
1065 
1066 static const TypeInfo sysbus_esp_info = {
1067     .name          = TYPE_SYSBUS_ESP,
1068     .parent        = TYPE_SYS_BUS_DEVICE,
1069     .instance_init = sysbus_esp_init,
1070     .instance_size = sizeof(SysBusESPState),
1071     .class_init    = sysbus_esp_class_init,
1072 };
1073 
1074 static void esp_class_init(ObjectClass *klass, void *data)
1075 {
1076     DeviceClass *dc = DEVICE_CLASS(klass);
1077 
1078     /* internal device for sysbusesp/pciespscsi, not user-creatable */
1079     dc->user_creatable = false;
1080     set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
1081 }
1082 
1083 static const TypeInfo esp_info = {
1084     .name = TYPE_ESP,
1085     .parent = TYPE_DEVICE,
1086     .instance_size = sizeof(ESPState),
1087     .class_init = esp_class_init,
1088 };
1089 
1090 static void esp_register_types(void)
1091 {
1092     type_register_static(&sysbus_esp_info);
1093     type_register_static(&esp_info);
1094 }
1095 
1096 type_init(esp_register_types)
1097