xref: /qemu/hw/ide/ahci.c (revision 3d5b3ec6)
1 /*
2  * QEMU AHCI Emulation
3  *
4  * Copyright (c) 2010 qiaochong@loongson.cn
5  * Copyright (c) 2010 Roland Elek <elek.roland@gmail.com>
6  * Copyright (c) 2010 Sebastian Herbszt <herbszt@gmx.de>
7  * Copyright (c) 2010 Alexander Graf <agraf@suse.de>
8  *
9  * This library is free software; you can redistribute it and/or
10  * modify it under the terms of the GNU Lesser General Public
11  * License as published by the Free Software Foundation; either
12  * version 2 of the License, or (at your option) any later version.
13  *
14  * This library is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
17  * Lesser General Public License for more details.
18  *
19  * You should have received a copy of the GNU Lesser General Public
20  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
21  *
22  */
23 
24 #include <hw/hw.h>
25 #include <hw/pci/msi.h>
26 #include <hw/i386/pc.h>
27 #include <hw/pci/pci.h>
28 #include <hw/sysbus.h>
29 
30 #include "monitor/monitor.h"
31 #include "sysemu/dma.h"
32 #include "internal.h"
33 #include <hw/ide/pci.h>
34 #include <hw/ide/ahci.h>
35 
36 /* #define DEBUG_AHCI */
37 
38 #ifdef DEBUG_AHCI
39 #define DPRINTF(port, fmt, ...) \
40 do { fprintf(stderr, "ahci: %s: [%d] ", __FUNCTION__, port); \
41      fprintf(stderr, fmt, ## __VA_ARGS__); } while (0)
42 #else
43 #define DPRINTF(port, fmt, ...) do {} while(0)
44 #endif
45 
46 static void check_cmd(AHCIState *s, int port);
47 static int handle_cmd(AHCIState *s,int port,int slot);
48 static void ahci_reset_port(AHCIState *s, int port);
49 static void ahci_write_fis_d2h(AHCIDevice *ad, uint8_t *cmd_fis);
50 static void ahci_init_d2h(AHCIDevice *ad);
51 
52 static uint32_t  ahci_port_read(AHCIState *s, int port, int offset)
53 {
54     uint32_t val;
55     AHCIPortRegs *pr;
56     pr = &s->dev[port].port_regs;
57 
58     switch (offset) {
59     case PORT_LST_ADDR:
60         val = pr->lst_addr;
61         break;
62     case PORT_LST_ADDR_HI:
63         val = pr->lst_addr_hi;
64         break;
65     case PORT_FIS_ADDR:
66         val = pr->fis_addr;
67         break;
68     case PORT_FIS_ADDR_HI:
69         val = pr->fis_addr_hi;
70         break;
71     case PORT_IRQ_STAT:
72         val = pr->irq_stat;
73         break;
74     case PORT_IRQ_MASK:
75         val = pr->irq_mask;
76         break;
77     case PORT_CMD:
78         val = pr->cmd;
79         break;
80     case PORT_TFDATA:
81         val = ((uint16_t)s->dev[port].port.ifs[0].error << 8) |
82               s->dev[port].port.ifs[0].status;
83         break;
84     case PORT_SIG:
85         val = pr->sig;
86         break;
87     case PORT_SCR_STAT:
88         if (s->dev[port].port.ifs[0].bs) {
89             val = SATA_SCR_SSTATUS_DET_DEV_PRESENT_PHY_UP |
90                   SATA_SCR_SSTATUS_SPD_GEN1 | SATA_SCR_SSTATUS_IPM_ACTIVE;
91         } else {
92             val = SATA_SCR_SSTATUS_DET_NODEV;
93         }
94         break;
95     case PORT_SCR_CTL:
96         val = pr->scr_ctl;
97         break;
98     case PORT_SCR_ERR:
99         val = pr->scr_err;
100         break;
101     case PORT_SCR_ACT:
102         pr->scr_act &= ~s->dev[port].finished;
103         s->dev[port].finished = 0;
104         val = pr->scr_act;
105         break;
106     case PORT_CMD_ISSUE:
107         val = pr->cmd_issue;
108         break;
109     case PORT_RESERVED:
110     default:
111         val = 0;
112     }
113     DPRINTF(port, "offset: 0x%x val: 0x%x\n", offset, val);
114     return val;
115 
116 }
117 
118 static void ahci_irq_raise(AHCIState *s, AHCIDevice *dev)
119 {
120     struct AHCIPCIState *d = container_of(s, AHCIPCIState, ahci);
121 
122     DPRINTF(0, "raise irq\n");
123 
124     if (msi_enabled(&d->card)) {
125         msi_notify(&d->card, 0);
126     } else {
127         qemu_irq_raise(s->irq);
128     }
129 }
130 
131 static void ahci_irq_lower(AHCIState *s, AHCIDevice *dev)
132 {
133     struct AHCIPCIState *d = container_of(s, AHCIPCIState, ahci);
134 
135     DPRINTF(0, "lower irq\n");
136 
137     if (!msi_enabled(&d->card)) {
138         qemu_irq_lower(s->irq);
139     }
140 }
141 
142 static void ahci_check_irq(AHCIState *s)
143 {
144     int i;
145 
146     DPRINTF(-1, "check irq %#x\n", s->control_regs.irqstatus);
147 
148     s->control_regs.irqstatus = 0;
149     for (i = 0; i < s->ports; i++) {
150         AHCIPortRegs *pr = &s->dev[i].port_regs;
151         if (pr->irq_stat & pr->irq_mask) {
152             s->control_regs.irqstatus |= (1 << i);
153         }
154     }
155 
156     if (s->control_regs.irqstatus &&
157         (s->control_regs.ghc & HOST_CTL_IRQ_EN)) {
158             ahci_irq_raise(s, NULL);
159     } else {
160         ahci_irq_lower(s, NULL);
161     }
162 }
163 
164 static void ahci_trigger_irq(AHCIState *s, AHCIDevice *d,
165                              int irq_type)
166 {
167     DPRINTF(d->port_no, "trigger irq %#x -> %x\n",
168             irq_type, d->port_regs.irq_mask & irq_type);
169 
170     d->port_regs.irq_stat |= irq_type;
171     ahci_check_irq(s);
172 }
173 
174 static void map_page(uint8_t **ptr, uint64_t addr, uint32_t wanted)
175 {
176     hwaddr len = wanted;
177 
178     if (*ptr) {
179         cpu_physical_memory_unmap(*ptr, len, 1, len);
180     }
181 
182     *ptr = cpu_physical_memory_map(addr, &len, 1);
183     if (len < wanted) {
184         cpu_physical_memory_unmap(*ptr, len, 1, len);
185         *ptr = NULL;
186     }
187 }
188 
189 static void  ahci_port_write(AHCIState *s, int port, int offset, uint32_t val)
190 {
191     AHCIPortRegs *pr = &s->dev[port].port_regs;
192 
193     DPRINTF(port, "offset: 0x%x val: 0x%x\n", offset, val);
194     switch (offset) {
195         case PORT_LST_ADDR:
196             pr->lst_addr = val;
197             map_page(&s->dev[port].lst,
198                      ((uint64_t)pr->lst_addr_hi << 32) | pr->lst_addr, 1024);
199             s->dev[port].cur_cmd = NULL;
200             break;
201         case PORT_LST_ADDR_HI:
202             pr->lst_addr_hi = val;
203             map_page(&s->dev[port].lst,
204                      ((uint64_t)pr->lst_addr_hi << 32) | pr->lst_addr, 1024);
205             s->dev[port].cur_cmd = NULL;
206             break;
207         case PORT_FIS_ADDR:
208             pr->fis_addr = val;
209             map_page(&s->dev[port].res_fis,
210                      ((uint64_t)pr->fis_addr_hi << 32) | pr->fis_addr, 256);
211             break;
212         case PORT_FIS_ADDR_HI:
213             pr->fis_addr_hi = val;
214             map_page(&s->dev[port].res_fis,
215                      ((uint64_t)pr->fis_addr_hi << 32) | pr->fis_addr, 256);
216             break;
217         case PORT_IRQ_STAT:
218             pr->irq_stat &= ~val;
219             ahci_check_irq(s);
220             break;
221         case PORT_IRQ_MASK:
222             pr->irq_mask = val & 0xfdc000ff;
223             ahci_check_irq(s);
224             break;
225         case PORT_CMD:
226             pr->cmd = val & ~(PORT_CMD_LIST_ON | PORT_CMD_FIS_ON);
227 
228             if (pr->cmd & PORT_CMD_START) {
229                 pr->cmd |= PORT_CMD_LIST_ON;
230             }
231 
232             if (pr->cmd & PORT_CMD_FIS_RX) {
233                 pr->cmd |= PORT_CMD_FIS_ON;
234             }
235 
236             /* XXX usually the FIS would be pending on the bus here and
237                    issuing deferred until the OS enables FIS receival.
238                    Instead, we only submit it once - which works in most
239                    cases, but is a hack. */
240             if ((pr->cmd & PORT_CMD_FIS_ON) &&
241                 !s->dev[port].init_d2h_sent) {
242                 ahci_init_d2h(&s->dev[port]);
243                 s->dev[port].init_d2h_sent = true;
244             }
245 
246             check_cmd(s, port);
247             break;
248         case PORT_TFDATA:
249             s->dev[port].port.ifs[0].error = (val >> 8) & 0xff;
250             s->dev[port].port.ifs[0].status = val & 0xff;
251             break;
252         case PORT_SIG:
253             pr->sig = val;
254             break;
255         case PORT_SCR_STAT:
256             pr->scr_stat = val;
257             break;
258         case PORT_SCR_CTL:
259             if (((pr->scr_ctl & AHCI_SCR_SCTL_DET) == 1) &&
260                 ((val & AHCI_SCR_SCTL_DET) == 0)) {
261                 ahci_reset_port(s, port);
262             }
263             pr->scr_ctl = val;
264             break;
265         case PORT_SCR_ERR:
266             pr->scr_err &= ~val;
267             break;
268         case PORT_SCR_ACT:
269             /* RW1 */
270             pr->scr_act |= val;
271             break;
272         case PORT_CMD_ISSUE:
273             pr->cmd_issue |= val;
274             check_cmd(s, port);
275             break;
276         default:
277             break;
278     }
279 }
280 
281 static uint64_t ahci_mem_read(void *opaque, hwaddr addr,
282                               unsigned size)
283 {
284     AHCIState *s = opaque;
285     uint32_t val = 0;
286 
287     if (addr < AHCI_GENERIC_HOST_CONTROL_REGS_MAX_ADDR) {
288         switch (addr) {
289         case HOST_CAP:
290             val = s->control_regs.cap;
291             break;
292         case HOST_CTL:
293             val = s->control_regs.ghc;
294             break;
295         case HOST_IRQ_STAT:
296             val = s->control_regs.irqstatus;
297             break;
298         case HOST_PORTS_IMPL:
299             val = s->control_regs.impl;
300             break;
301         case HOST_VERSION:
302             val = s->control_regs.version;
303             break;
304         }
305 
306         DPRINTF(-1, "(addr 0x%08X), val 0x%08X\n", (unsigned) addr, val);
307     } else if ((addr >= AHCI_PORT_REGS_START_ADDR) &&
308                (addr < (AHCI_PORT_REGS_START_ADDR +
309                 (s->ports * AHCI_PORT_ADDR_OFFSET_LEN)))) {
310         val = ahci_port_read(s, (addr - AHCI_PORT_REGS_START_ADDR) >> 7,
311                              addr & AHCI_PORT_ADDR_OFFSET_MASK);
312     }
313 
314     return val;
315 }
316 
317 
318 
319 static void ahci_mem_write(void *opaque, hwaddr addr,
320                            uint64_t val, unsigned size)
321 {
322     AHCIState *s = opaque;
323 
324     /* Only aligned reads are allowed on AHCI */
325     if (addr & 3) {
326         fprintf(stderr, "ahci: Mis-aligned write to addr 0x"
327                 TARGET_FMT_plx "\n", addr);
328         return;
329     }
330 
331     if (addr < AHCI_GENERIC_HOST_CONTROL_REGS_MAX_ADDR) {
332         DPRINTF(-1, "(addr 0x%08X), val 0x%08"PRIX64"\n", (unsigned) addr, val);
333 
334         switch (addr) {
335             case HOST_CAP: /* R/WO, RO */
336                 /* FIXME handle R/WO */
337                 break;
338             case HOST_CTL: /* R/W */
339                 if (val & HOST_CTL_RESET) {
340                     DPRINTF(-1, "HBA Reset\n");
341                     ahci_reset(s);
342                 } else {
343                     s->control_regs.ghc = (val & 0x3) | HOST_CTL_AHCI_EN;
344                     ahci_check_irq(s);
345                 }
346                 break;
347             case HOST_IRQ_STAT: /* R/WC, RO */
348                 s->control_regs.irqstatus &= ~val;
349                 ahci_check_irq(s);
350                 break;
351             case HOST_PORTS_IMPL: /* R/WO, RO */
352                 /* FIXME handle R/WO */
353                 break;
354             case HOST_VERSION: /* RO */
355                 /* FIXME report write? */
356                 break;
357             default:
358                 DPRINTF(-1, "write to unknown register 0x%x\n", (unsigned)addr);
359         }
360     } else if ((addr >= AHCI_PORT_REGS_START_ADDR) &&
361                (addr < (AHCI_PORT_REGS_START_ADDR +
362                 (s->ports * AHCI_PORT_ADDR_OFFSET_LEN)))) {
363         ahci_port_write(s, (addr - AHCI_PORT_REGS_START_ADDR) >> 7,
364                         addr & AHCI_PORT_ADDR_OFFSET_MASK, val);
365     }
366 
367 }
368 
369 static const MemoryRegionOps ahci_mem_ops = {
370     .read = ahci_mem_read,
371     .write = ahci_mem_write,
372     .endianness = DEVICE_LITTLE_ENDIAN,
373 };
374 
375 static uint64_t ahci_idp_read(void *opaque, hwaddr addr,
376                               unsigned size)
377 {
378     AHCIState *s = opaque;
379 
380     if (addr == s->idp_offset) {
381         /* index register */
382         return s->idp_index;
383     } else if (addr == s->idp_offset + 4) {
384         /* data register - do memory read at location selected by index */
385         return ahci_mem_read(opaque, s->idp_index, size);
386     } else {
387         return 0;
388     }
389 }
390 
391 static void ahci_idp_write(void *opaque, hwaddr addr,
392                            uint64_t val, unsigned size)
393 {
394     AHCIState *s = opaque;
395 
396     if (addr == s->idp_offset) {
397         /* index register - mask off reserved bits */
398         s->idp_index = (uint32_t)val & ((AHCI_MEM_BAR_SIZE - 1) & ~3);
399     } else if (addr == s->idp_offset + 4) {
400         /* data register - do memory write at location selected by index */
401         ahci_mem_write(opaque, s->idp_index, val, size);
402     }
403 }
404 
405 static const MemoryRegionOps ahci_idp_ops = {
406     .read = ahci_idp_read,
407     .write = ahci_idp_write,
408     .endianness = DEVICE_LITTLE_ENDIAN,
409 };
410 
411 
412 static void ahci_reg_init(AHCIState *s)
413 {
414     int i;
415 
416     s->control_regs.cap = (s->ports - 1) |
417                           (AHCI_NUM_COMMAND_SLOTS << 8) |
418                           (AHCI_SUPPORTED_SPEED_GEN1 << AHCI_SUPPORTED_SPEED) |
419                           HOST_CAP_NCQ | HOST_CAP_AHCI;
420 
421     s->control_regs.impl = (1 << s->ports) - 1;
422 
423     s->control_regs.version = AHCI_VERSION_1_0;
424 
425     for (i = 0; i < s->ports; i++) {
426         s->dev[i].port_state = STATE_RUN;
427     }
428 }
429 
430 static void check_cmd(AHCIState *s, int port)
431 {
432     AHCIPortRegs *pr = &s->dev[port].port_regs;
433     int slot;
434 
435     if ((pr->cmd & PORT_CMD_START) && pr->cmd_issue) {
436         for (slot = 0; (slot < 32) && pr->cmd_issue; slot++) {
437             if ((pr->cmd_issue & (1 << slot)) &&
438                 !handle_cmd(s, port, slot)) {
439                 pr->cmd_issue &= ~(1 << slot);
440             }
441         }
442     }
443 }
444 
445 static void ahci_check_cmd_bh(void *opaque)
446 {
447     AHCIDevice *ad = opaque;
448 
449     qemu_bh_delete(ad->check_bh);
450     ad->check_bh = NULL;
451 
452     if ((ad->busy_slot != -1) &&
453         !(ad->port.ifs[0].status & (BUSY_STAT|DRQ_STAT))) {
454         /* no longer busy */
455         ad->port_regs.cmd_issue &= ~(1 << ad->busy_slot);
456         ad->busy_slot = -1;
457     }
458 
459     check_cmd(ad->hba, ad->port_no);
460 }
461 
462 static void ahci_init_d2h(AHCIDevice *ad)
463 {
464     uint8_t init_fis[20];
465     IDEState *ide_state = &ad->port.ifs[0];
466 
467     memset(init_fis, 0, sizeof(init_fis));
468 
469     init_fis[4] = 1;
470     init_fis[12] = 1;
471 
472     if (ide_state->drive_kind == IDE_CD) {
473         init_fis[5] = ide_state->lcyl;
474         init_fis[6] = ide_state->hcyl;
475     }
476 
477     ahci_write_fis_d2h(ad, init_fis);
478 }
479 
480 static void ahci_reset_port(AHCIState *s, int port)
481 {
482     AHCIDevice *d = &s->dev[port];
483     AHCIPortRegs *pr = &d->port_regs;
484     IDEState *ide_state = &d->port.ifs[0];
485     int i;
486 
487     DPRINTF(port, "reset port\n");
488 
489     ide_bus_reset(&d->port);
490     ide_state->ncq_queues = AHCI_MAX_CMDS;
491 
492     pr->scr_stat = 0;
493     pr->scr_err = 0;
494     pr->scr_act = 0;
495     d->busy_slot = -1;
496     d->init_d2h_sent = false;
497 
498     ide_state = &s->dev[port].port.ifs[0];
499     if (!ide_state->bs) {
500         return;
501     }
502 
503     /* reset ncq queue */
504     for (i = 0; i < AHCI_MAX_CMDS; i++) {
505         NCQTransferState *ncq_tfs = &s->dev[port].ncq_tfs[i];
506         if (!ncq_tfs->used) {
507             continue;
508         }
509 
510         if (ncq_tfs->aiocb) {
511             bdrv_aio_cancel(ncq_tfs->aiocb);
512             ncq_tfs->aiocb = NULL;
513         }
514 
515         /* Maybe we just finished the request thanks to bdrv_aio_cancel() */
516         if (!ncq_tfs->used) {
517             continue;
518         }
519 
520         qemu_sglist_destroy(&ncq_tfs->sglist);
521         ncq_tfs->used = 0;
522     }
523 
524     s->dev[port].port_state = STATE_RUN;
525     if (!ide_state->bs) {
526         s->dev[port].port_regs.sig = 0;
527         ide_state->status = SEEK_STAT | WRERR_STAT;
528     } else if (ide_state->drive_kind == IDE_CD) {
529         s->dev[port].port_regs.sig = SATA_SIGNATURE_CDROM;
530         ide_state->lcyl = 0x14;
531         ide_state->hcyl = 0xeb;
532         DPRINTF(port, "set lcyl = %d\n", ide_state->lcyl);
533         ide_state->status = SEEK_STAT | WRERR_STAT | READY_STAT;
534     } else {
535         s->dev[port].port_regs.sig = SATA_SIGNATURE_DISK;
536         ide_state->status = SEEK_STAT | WRERR_STAT;
537     }
538 
539     ide_state->error = 1;
540     ahci_init_d2h(d);
541 }
542 
543 static void debug_print_fis(uint8_t *fis, int cmd_len)
544 {
545 #ifdef DEBUG_AHCI
546     int i;
547 
548     fprintf(stderr, "fis:");
549     for (i = 0; i < cmd_len; i++) {
550         if ((i & 0xf) == 0) {
551             fprintf(stderr, "\n%02x:",i);
552         }
553         fprintf(stderr, "%02x ",fis[i]);
554     }
555     fprintf(stderr, "\n");
556 #endif
557 }
558 
559 static void ahci_write_fis_sdb(AHCIState *s, int port, uint32_t finished)
560 {
561     AHCIPortRegs *pr = &s->dev[port].port_regs;
562     IDEState *ide_state;
563     uint8_t *sdb_fis;
564 
565     if (!s->dev[port].res_fis ||
566         !(pr->cmd & PORT_CMD_FIS_RX)) {
567         return;
568     }
569 
570     sdb_fis = &s->dev[port].res_fis[RES_FIS_SDBFIS];
571     ide_state = &s->dev[port].port.ifs[0];
572 
573     /* clear memory */
574     *(uint32_t*)sdb_fis = 0;
575 
576     /* write values */
577     sdb_fis[0] = ide_state->error;
578     sdb_fis[2] = ide_state->status & 0x77;
579     s->dev[port].finished |= finished;
580     *(uint32_t*)(sdb_fis + 4) = cpu_to_le32(s->dev[port].finished);
581 
582     ahci_trigger_irq(s, &s->dev[port], PORT_IRQ_STAT_SDBS);
583 }
584 
585 static void ahci_write_fis_d2h(AHCIDevice *ad, uint8_t *cmd_fis)
586 {
587     AHCIPortRegs *pr = &ad->port_regs;
588     uint8_t *d2h_fis;
589     int i;
590     dma_addr_t cmd_len = 0x80;
591     int cmd_mapped = 0;
592 
593     if (!ad->res_fis || !(pr->cmd & PORT_CMD_FIS_RX)) {
594         return;
595     }
596 
597     if (!cmd_fis) {
598         /* map cmd_fis */
599         uint64_t tbl_addr = le64_to_cpu(ad->cur_cmd->tbl_addr);
600         cmd_fis = dma_memory_map(ad->hba->dma, tbl_addr, &cmd_len,
601                                  DMA_DIRECTION_TO_DEVICE);
602         cmd_mapped = 1;
603     }
604 
605     d2h_fis = &ad->res_fis[RES_FIS_RFIS];
606 
607     d2h_fis[0] = 0x34;
608     d2h_fis[1] = (ad->hba->control_regs.irqstatus ? (1 << 6) : 0);
609     d2h_fis[2] = ad->port.ifs[0].status;
610     d2h_fis[3] = ad->port.ifs[0].error;
611 
612     d2h_fis[4] = cmd_fis[4];
613     d2h_fis[5] = cmd_fis[5];
614     d2h_fis[6] = cmd_fis[6];
615     d2h_fis[7] = cmd_fis[7];
616     d2h_fis[8] = cmd_fis[8];
617     d2h_fis[9] = cmd_fis[9];
618     d2h_fis[10] = cmd_fis[10];
619     d2h_fis[11] = cmd_fis[11];
620     d2h_fis[12] = cmd_fis[12];
621     d2h_fis[13] = cmd_fis[13];
622     for (i = 14; i < 20; i++) {
623         d2h_fis[i] = 0;
624     }
625 
626     if (d2h_fis[2] & ERR_STAT) {
627         ahci_trigger_irq(ad->hba, ad, PORT_IRQ_STAT_TFES);
628     }
629 
630     ahci_trigger_irq(ad->hba, ad, PORT_IRQ_D2H_REG_FIS);
631 
632     if (cmd_mapped) {
633         dma_memory_unmap(ad->hba->dma, cmd_fis, cmd_len,
634                          DMA_DIRECTION_TO_DEVICE, cmd_len);
635     }
636 }
637 
638 static int ahci_populate_sglist(AHCIDevice *ad, QEMUSGList *sglist, int offset)
639 {
640     AHCICmdHdr *cmd = ad->cur_cmd;
641     uint32_t opts = le32_to_cpu(cmd->opts);
642     uint64_t prdt_addr = le64_to_cpu(cmd->tbl_addr) + 0x80;
643     int sglist_alloc_hint = opts >> AHCI_CMD_HDR_PRDT_LEN;
644     dma_addr_t prdt_len = (sglist_alloc_hint * sizeof(AHCI_SG));
645     dma_addr_t real_prdt_len = prdt_len;
646     uint8_t *prdt;
647     int i;
648     int r = 0;
649     int sum = 0;
650     int off_idx = -1;
651     int off_pos = -1;
652     int tbl_entry_size;
653 
654     if (!sglist_alloc_hint) {
655         DPRINTF(ad->port_no, "no sg list given by guest: 0x%08x\n", opts);
656         return -1;
657     }
658 
659     /* map PRDT */
660     if (!(prdt = dma_memory_map(ad->hba->dma, prdt_addr, &prdt_len,
661                                 DMA_DIRECTION_TO_DEVICE))){
662         DPRINTF(ad->port_no, "map failed\n");
663         return -1;
664     }
665 
666     if (prdt_len < real_prdt_len) {
667         DPRINTF(ad->port_no, "mapped less than expected\n");
668         r = -1;
669         goto out;
670     }
671 
672     /* Get entries in the PRDT, init a qemu sglist accordingly */
673     if (sglist_alloc_hint > 0) {
674         AHCI_SG *tbl = (AHCI_SG *)prdt;
675         sum = 0;
676         for (i = 0; i < sglist_alloc_hint; i++) {
677             /* flags_size is zero-based */
678             tbl_entry_size = (le32_to_cpu(tbl[i].flags_size) + 1);
679             if (offset <= (sum + tbl_entry_size)) {
680                 off_idx = i;
681                 off_pos = offset - sum;
682                 break;
683             }
684             sum += tbl_entry_size;
685         }
686         if ((off_idx == -1) || (off_pos < 0) || (off_pos > tbl_entry_size)) {
687             DPRINTF(ad->port_no, "%s: Incorrect offset! "
688                             "off_idx: %d, off_pos: %d\n",
689                             __func__, off_idx, off_pos);
690             r = -1;
691             goto out;
692         }
693 
694         qemu_sglist_init(sglist, (sglist_alloc_hint - off_idx), ad->hba->dma);
695         qemu_sglist_add(sglist, le64_to_cpu(tbl[off_idx].addr + off_pos),
696                         le32_to_cpu(tbl[off_idx].flags_size) + 1 - off_pos);
697 
698         for (i = off_idx + 1; i < sglist_alloc_hint; i++) {
699             /* flags_size is zero-based */
700             qemu_sglist_add(sglist, le64_to_cpu(tbl[i].addr),
701                             le32_to_cpu(tbl[i].flags_size) + 1);
702         }
703     }
704 
705 out:
706     dma_memory_unmap(ad->hba->dma, prdt, prdt_len,
707                      DMA_DIRECTION_TO_DEVICE, prdt_len);
708     return r;
709 }
710 
711 static void ncq_cb(void *opaque, int ret)
712 {
713     NCQTransferState *ncq_tfs = (NCQTransferState *)opaque;
714     IDEState *ide_state = &ncq_tfs->drive->port.ifs[0];
715 
716     /* Clear bit for this tag in SActive */
717     ncq_tfs->drive->port_regs.scr_act &= ~(1 << ncq_tfs->tag);
718 
719     if (ret < 0) {
720         /* error */
721         ide_state->error = ABRT_ERR;
722         ide_state->status = READY_STAT | ERR_STAT;
723         ncq_tfs->drive->port_regs.scr_err |= (1 << ncq_tfs->tag);
724     } else {
725         ide_state->status = READY_STAT | SEEK_STAT;
726     }
727 
728     ahci_write_fis_sdb(ncq_tfs->drive->hba, ncq_tfs->drive->port_no,
729                        (1 << ncq_tfs->tag));
730 
731     DPRINTF(ncq_tfs->drive->port_no, "NCQ transfer tag %d finished\n",
732             ncq_tfs->tag);
733 
734     bdrv_acct_done(ncq_tfs->drive->port.ifs[0].bs, &ncq_tfs->acct);
735     qemu_sglist_destroy(&ncq_tfs->sglist);
736     ncq_tfs->used = 0;
737 }
738 
739 static void process_ncq_command(AHCIState *s, int port, uint8_t *cmd_fis,
740                                 int slot)
741 {
742     NCQFrame *ncq_fis = (NCQFrame*)cmd_fis;
743     uint8_t tag = ncq_fis->tag >> 3;
744     NCQTransferState *ncq_tfs = &s->dev[port].ncq_tfs[tag];
745 
746     if (ncq_tfs->used) {
747         /* error - already in use */
748         fprintf(stderr, "%s: tag %d already used\n", __FUNCTION__, tag);
749         return;
750     }
751 
752     ncq_tfs->used = 1;
753     ncq_tfs->drive = &s->dev[port];
754     ncq_tfs->slot = slot;
755     ncq_tfs->lba = ((uint64_t)ncq_fis->lba5 << 40) |
756                    ((uint64_t)ncq_fis->lba4 << 32) |
757                    ((uint64_t)ncq_fis->lba3 << 24) |
758                    ((uint64_t)ncq_fis->lba2 << 16) |
759                    ((uint64_t)ncq_fis->lba1 << 8) |
760                    (uint64_t)ncq_fis->lba0;
761 
762     /* Note: We calculate the sector count, but don't currently rely on it.
763      * The total size of the DMA buffer tells us the transfer size instead. */
764     ncq_tfs->sector_count = ((uint16_t)ncq_fis->sector_count_high << 8) |
765                                 ncq_fis->sector_count_low;
766 
767     DPRINTF(port, "NCQ transfer LBA from %"PRId64" to %"PRId64", "
768             "drive max %"PRId64"\n",
769             ncq_tfs->lba, ncq_tfs->lba + ncq_tfs->sector_count - 2,
770             s->dev[port].port.ifs[0].nb_sectors - 1);
771 
772     ahci_populate_sglist(&s->dev[port], &ncq_tfs->sglist, 0);
773     ncq_tfs->tag = tag;
774 
775     switch(ncq_fis->command) {
776         case READ_FPDMA_QUEUED:
777             DPRINTF(port, "NCQ reading %d sectors from LBA %"PRId64", "
778                     "tag %d\n",
779                     ncq_tfs->sector_count-1, ncq_tfs->lba, ncq_tfs->tag);
780 
781             DPRINTF(port, "tag %d aio read %"PRId64"\n",
782                     ncq_tfs->tag, ncq_tfs->lba);
783 
784             dma_acct_start(ncq_tfs->drive->port.ifs[0].bs, &ncq_tfs->acct,
785                            &ncq_tfs->sglist, BDRV_ACCT_READ);
786             ncq_tfs->aiocb = dma_bdrv_read(ncq_tfs->drive->port.ifs[0].bs,
787                                            &ncq_tfs->sglist, ncq_tfs->lba,
788                                            ncq_cb, ncq_tfs);
789             break;
790         case WRITE_FPDMA_QUEUED:
791             DPRINTF(port, "NCQ writing %d sectors to LBA %"PRId64", tag %d\n",
792                     ncq_tfs->sector_count-1, ncq_tfs->lba, ncq_tfs->tag);
793 
794             DPRINTF(port, "tag %d aio write %"PRId64"\n",
795                     ncq_tfs->tag, ncq_tfs->lba);
796 
797             dma_acct_start(ncq_tfs->drive->port.ifs[0].bs, &ncq_tfs->acct,
798                            &ncq_tfs->sglist, BDRV_ACCT_WRITE);
799             ncq_tfs->aiocb = dma_bdrv_write(ncq_tfs->drive->port.ifs[0].bs,
800                                             &ncq_tfs->sglist, ncq_tfs->lba,
801                                             ncq_cb, ncq_tfs);
802             break;
803         default:
804             DPRINTF(port, "error: tried to process non-NCQ command as NCQ\n");
805             qemu_sglist_destroy(&ncq_tfs->sglist);
806             break;
807     }
808 }
809 
810 static int handle_cmd(AHCIState *s, int port, int slot)
811 {
812     IDEState *ide_state;
813     uint32_t opts;
814     uint64_t tbl_addr;
815     AHCICmdHdr *cmd;
816     uint8_t *cmd_fis;
817     dma_addr_t cmd_len;
818 
819     if (s->dev[port].port.ifs[0].status & (BUSY_STAT|DRQ_STAT)) {
820         /* Engine currently busy, try again later */
821         DPRINTF(port, "engine busy\n");
822         return -1;
823     }
824 
825     cmd = &((AHCICmdHdr *)s->dev[port].lst)[slot];
826 
827     if (!s->dev[port].lst) {
828         DPRINTF(port, "error: lst not given but cmd handled");
829         return -1;
830     }
831 
832     /* remember current slot handle for later */
833     s->dev[port].cur_cmd = cmd;
834 
835     opts = le32_to_cpu(cmd->opts);
836     tbl_addr = le64_to_cpu(cmd->tbl_addr);
837 
838     cmd_len = 0x80;
839     cmd_fis = dma_memory_map(s->dma, tbl_addr, &cmd_len,
840                              DMA_DIRECTION_FROM_DEVICE);
841 
842     if (!cmd_fis) {
843         DPRINTF(port, "error: guest passed us an invalid cmd fis\n");
844         return -1;
845     }
846 
847     /* The device we are working for */
848     ide_state = &s->dev[port].port.ifs[0];
849 
850     if (!ide_state->bs) {
851         DPRINTF(port, "error: guest accessed unused port");
852         goto out;
853     }
854 
855     debug_print_fis(cmd_fis, 0x90);
856     //debug_print_fis(cmd_fis, (opts & AHCI_CMD_HDR_CMD_FIS_LEN) * 4);
857 
858     switch (cmd_fis[0]) {
859         case SATA_FIS_TYPE_REGISTER_H2D:
860             break;
861         default:
862             DPRINTF(port, "unknown command cmd_fis[0]=%02x cmd_fis[1]=%02x "
863                           "cmd_fis[2]=%02x\n", cmd_fis[0], cmd_fis[1],
864                           cmd_fis[2]);
865             goto out;
866             break;
867     }
868 
869     switch (cmd_fis[1]) {
870         case SATA_FIS_REG_H2D_UPDATE_COMMAND_REGISTER:
871             break;
872         case 0:
873             break;
874         default:
875             DPRINTF(port, "unknown command cmd_fis[0]=%02x cmd_fis[1]=%02x "
876                           "cmd_fis[2]=%02x\n", cmd_fis[0], cmd_fis[1],
877                           cmd_fis[2]);
878             goto out;
879             break;
880     }
881 
882     switch (s->dev[port].port_state) {
883         case STATE_RUN:
884             if (cmd_fis[15] & ATA_SRST) {
885                 s->dev[port].port_state = STATE_RESET;
886             }
887             break;
888         case STATE_RESET:
889             if (!(cmd_fis[15] & ATA_SRST)) {
890                 ahci_reset_port(s, port);
891             }
892             break;
893     }
894 
895     if (cmd_fis[1] == SATA_FIS_REG_H2D_UPDATE_COMMAND_REGISTER) {
896 
897         /* Check for NCQ command */
898         if ((cmd_fis[2] == READ_FPDMA_QUEUED) ||
899             (cmd_fis[2] == WRITE_FPDMA_QUEUED)) {
900             process_ncq_command(s, port, cmd_fis, slot);
901             goto out;
902         }
903 
904         /* Decompose the FIS  */
905         ide_state->nsector = (int64_t)((cmd_fis[13] << 8) | cmd_fis[12]);
906         ide_state->feature = cmd_fis[3];
907         if (!ide_state->nsector) {
908             ide_state->nsector = 256;
909         }
910 
911         if (ide_state->drive_kind != IDE_CD) {
912             /*
913              * We set the sector depending on the sector defined in the FIS.
914              * Unfortunately, the spec isn't exactly obvious on this one.
915              *
916              * Apparently LBA48 commands set fis bytes 10,9,8,6,5,4 to the
917              * 48 bit sector number. ATA_CMD_READ_DMA_EXT is an example for
918              * such a command.
919              *
920              * Non-LBA48 commands however use 7[lower 4 bits],6,5,4 to define a
921              * 28-bit sector number. ATA_CMD_READ_DMA is an example for such
922              * a command.
923              *
924              * Since the spec doesn't explicitly state what each field should
925              * do, I simply assume non-used fields as reserved and OR everything
926              * together, independent of the command.
927              */
928             ide_set_sector(ide_state, ((uint64_t)cmd_fis[10] << 40)
929                                     | ((uint64_t)cmd_fis[9] << 32)
930                                     /* This is used for LBA48 commands */
931                                     | ((uint64_t)cmd_fis[8] << 24)
932                                     /* This is used for non-LBA48 commands */
933                                     | ((uint64_t)(cmd_fis[7] & 0xf) << 24)
934                                     | ((uint64_t)cmd_fis[6] << 16)
935                                     | ((uint64_t)cmd_fis[5] << 8)
936                                     | cmd_fis[4]);
937         }
938 
939         /* Copy the ACMD field (ATAPI packet, if any) from the AHCI command
940          * table to ide_state->io_buffer
941          */
942         if (opts & AHCI_CMD_ATAPI) {
943             memcpy(ide_state->io_buffer, &cmd_fis[AHCI_COMMAND_TABLE_ACMD], 0x10);
944             ide_state->lcyl = 0x14;
945             ide_state->hcyl = 0xeb;
946             debug_print_fis(ide_state->io_buffer, 0x10);
947             ide_state->feature = IDE_FEATURE_DMA;
948             s->dev[port].done_atapi_packet = false;
949             /* XXX send PIO setup FIS */
950         }
951 
952         ide_state->error = 0;
953 
954         /* Reset transferred byte counter */
955         cmd->status = 0;
956 
957         /* We're ready to process the command in FIS byte 2. */
958         ide_exec_cmd(&s->dev[port].port, cmd_fis[2]);
959 
960         if (s->dev[port].port.ifs[0].status & READY_STAT) {
961             ahci_write_fis_d2h(&s->dev[port], cmd_fis);
962         }
963     }
964 
965 out:
966     dma_memory_unmap(s->dma, cmd_fis, cmd_len, DMA_DIRECTION_FROM_DEVICE,
967                      cmd_len);
968 
969     if (s->dev[port].port.ifs[0].status & (BUSY_STAT|DRQ_STAT)) {
970         /* async command, complete later */
971         s->dev[port].busy_slot = slot;
972         return -1;
973     }
974 
975     /* done handling the command */
976     return 0;
977 }
978 
979 /* DMA dev <-> ram */
980 static int ahci_start_transfer(IDEDMA *dma)
981 {
982     AHCIDevice *ad = DO_UPCAST(AHCIDevice, dma, dma);
983     IDEState *s = &ad->port.ifs[0];
984     uint32_t size = (uint32_t)(s->data_end - s->data_ptr);
985     /* write == ram -> device */
986     uint32_t opts = le32_to_cpu(ad->cur_cmd->opts);
987     int is_write = opts & AHCI_CMD_WRITE;
988     int is_atapi = opts & AHCI_CMD_ATAPI;
989     int has_sglist = 0;
990 
991     if (is_atapi && !ad->done_atapi_packet) {
992         /* already prepopulated iobuffer */
993         ad->done_atapi_packet = true;
994         goto out;
995     }
996 
997     if (!ahci_populate_sglist(ad, &s->sg, 0)) {
998         has_sglist = 1;
999     }
1000 
1001     DPRINTF(ad->port_no, "%sing %d bytes on %s w/%s sglist\n",
1002             is_write ? "writ" : "read", size, is_atapi ? "atapi" : "ata",
1003             has_sglist ? "" : "o");
1004 
1005     if (has_sglist && size) {
1006         if (is_write) {
1007             dma_buf_write(s->data_ptr, size, &s->sg);
1008         } else {
1009             dma_buf_read(s->data_ptr, size, &s->sg);
1010         }
1011     }
1012 
1013     /* update number of transferred bytes */
1014     ad->cur_cmd->status = cpu_to_le32(le32_to_cpu(ad->cur_cmd->status) + size);
1015 
1016 out:
1017     /* declare that we processed everything */
1018     s->data_ptr = s->data_end;
1019 
1020     if (has_sglist) {
1021         qemu_sglist_destroy(&s->sg);
1022     }
1023 
1024     s->end_transfer_func(s);
1025 
1026     if (!(s->status & DRQ_STAT)) {
1027         /* done with DMA */
1028         ahci_trigger_irq(ad->hba, ad, PORT_IRQ_STAT_DSS);
1029     }
1030 
1031     return 0;
1032 }
1033 
1034 static void ahci_start_dma(IDEDMA *dma, IDEState *s,
1035                            BlockDriverCompletionFunc *dma_cb)
1036 {
1037 #ifdef DEBUG_AHCI
1038     AHCIDevice *ad = DO_UPCAST(AHCIDevice, dma, dma);
1039 #endif
1040     DPRINTF(ad->port_no, "\n");
1041     s->io_buffer_offset = 0;
1042     dma_cb(s, 0);
1043 }
1044 
1045 static int ahci_dma_prepare_buf(IDEDMA *dma, int is_write)
1046 {
1047     AHCIDevice *ad = DO_UPCAST(AHCIDevice, dma, dma);
1048     IDEState *s = &ad->port.ifs[0];
1049 
1050     ahci_populate_sglist(ad, &s->sg, 0);
1051     s->io_buffer_size = s->sg.size;
1052 
1053     DPRINTF(ad->port_no, "len=%#x\n", s->io_buffer_size);
1054     return s->io_buffer_size != 0;
1055 }
1056 
1057 static int ahci_dma_rw_buf(IDEDMA *dma, int is_write)
1058 {
1059     AHCIDevice *ad = DO_UPCAST(AHCIDevice, dma, dma);
1060     IDEState *s = &ad->port.ifs[0];
1061     uint8_t *p = s->io_buffer + s->io_buffer_index;
1062     int l = s->io_buffer_size - s->io_buffer_index;
1063 
1064     if (ahci_populate_sglist(ad, &s->sg, s->io_buffer_offset)) {
1065         return 0;
1066     }
1067 
1068     if (is_write) {
1069         dma_buf_read(p, l, &s->sg);
1070     } else {
1071         dma_buf_write(p, l, &s->sg);
1072     }
1073 
1074     /* free sglist that was created in ahci_populate_sglist() */
1075     qemu_sglist_destroy(&s->sg);
1076 
1077     /* update number of transferred bytes */
1078     ad->cur_cmd->status = cpu_to_le32(le32_to_cpu(ad->cur_cmd->status) + l);
1079     s->io_buffer_index += l;
1080     s->io_buffer_offset += l;
1081 
1082     DPRINTF(ad->port_no, "len=%#x\n", l);
1083 
1084     return 1;
1085 }
1086 
1087 static int ahci_dma_set_unit(IDEDMA *dma, int unit)
1088 {
1089     /* only a single unit per link */
1090     return 0;
1091 }
1092 
1093 static int ahci_dma_add_status(IDEDMA *dma, int status)
1094 {
1095     AHCIDevice *ad = DO_UPCAST(AHCIDevice, dma, dma);
1096     DPRINTF(ad->port_no, "set status: %x\n", status);
1097 
1098     if (status & BM_STATUS_INT) {
1099         ahci_trigger_irq(ad->hba, ad, PORT_IRQ_STAT_DSS);
1100     }
1101 
1102     return 0;
1103 }
1104 
1105 static int ahci_dma_set_inactive(IDEDMA *dma)
1106 {
1107     AHCIDevice *ad = DO_UPCAST(AHCIDevice, dma, dma);
1108 
1109     DPRINTF(ad->port_no, "dma done\n");
1110 
1111     /* update d2h status */
1112     ahci_write_fis_d2h(ad, NULL);
1113 
1114     if (!ad->check_bh) {
1115         /* maybe we still have something to process, check later */
1116         ad->check_bh = qemu_bh_new(ahci_check_cmd_bh, ad);
1117         qemu_bh_schedule(ad->check_bh);
1118     }
1119 
1120     return 0;
1121 }
1122 
1123 static void ahci_irq_set(void *opaque, int n, int level)
1124 {
1125 }
1126 
1127 static void ahci_dma_restart_cb(void *opaque, int running, RunState state)
1128 {
1129 }
1130 
1131 static int ahci_dma_reset(IDEDMA *dma)
1132 {
1133     return 0;
1134 }
1135 
1136 static const IDEDMAOps ahci_dma_ops = {
1137     .start_dma = ahci_start_dma,
1138     .start_transfer = ahci_start_transfer,
1139     .prepare_buf = ahci_dma_prepare_buf,
1140     .rw_buf = ahci_dma_rw_buf,
1141     .set_unit = ahci_dma_set_unit,
1142     .add_status = ahci_dma_add_status,
1143     .set_inactive = ahci_dma_set_inactive,
1144     .restart_cb = ahci_dma_restart_cb,
1145     .reset = ahci_dma_reset,
1146 };
1147 
1148 void ahci_init(AHCIState *s, DeviceState *qdev, DMAContext *dma, int ports)
1149 {
1150     qemu_irq *irqs;
1151     int i;
1152 
1153     s->dma = dma;
1154     s->ports = ports;
1155     s->dev = g_malloc0(sizeof(AHCIDevice) * ports);
1156     ahci_reg_init(s);
1157     /* XXX BAR size should be 1k, but that breaks, so bump it to 4k for now */
1158     memory_region_init_io(&s->mem, &ahci_mem_ops, s, "ahci", AHCI_MEM_BAR_SIZE);
1159     memory_region_init_io(&s->idp, &ahci_idp_ops, s, "ahci-idp", 32);
1160 
1161     irqs = qemu_allocate_irqs(ahci_irq_set, s, s->ports);
1162 
1163     for (i = 0; i < s->ports; i++) {
1164         AHCIDevice *ad = &s->dev[i];
1165 
1166         ide_bus_new(&ad->port, qdev, i, 1);
1167         ide_init2(&ad->port, irqs[i]);
1168 
1169         ad->hba = s;
1170         ad->port_no = i;
1171         ad->port.dma = &ad->dma;
1172         ad->port.dma->ops = &ahci_dma_ops;
1173     }
1174 }
1175 
1176 void ahci_uninit(AHCIState *s)
1177 {
1178     memory_region_destroy(&s->mem);
1179     memory_region_destroy(&s->idp);
1180     g_free(s->dev);
1181 }
1182 
1183 void ahci_reset(AHCIState *s)
1184 {
1185     AHCIPortRegs *pr;
1186     int i;
1187 
1188     s->control_regs.irqstatus = 0;
1189     s->control_regs.ghc = 0;
1190 
1191     for (i = 0; i < s->ports; i++) {
1192         pr = &s->dev[i].port_regs;
1193         pr->irq_stat = 0;
1194         pr->irq_mask = 0;
1195         pr->scr_ctl = 0;
1196         pr->cmd = PORT_CMD_SPIN_UP | PORT_CMD_POWER_ON;
1197         ahci_reset_port(s, i);
1198     }
1199 }
1200 
1201 static const VMStateDescription vmstate_ahci_device = {
1202     .name = "ahci port",
1203     .version_id = 1,
1204     .fields = (VMStateField []) {
1205         VMSTATE_IDE_BUS(port, AHCIDevice),
1206         VMSTATE_UINT32(port_state, AHCIDevice),
1207         VMSTATE_UINT32(finished, AHCIDevice),
1208         VMSTATE_UINT32(port_regs.lst_addr, AHCIDevice),
1209         VMSTATE_UINT32(port_regs.lst_addr_hi, AHCIDevice),
1210         VMSTATE_UINT32(port_regs.fis_addr, AHCIDevice),
1211         VMSTATE_UINT32(port_regs.fis_addr_hi, AHCIDevice),
1212         VMSTATE_UINT32(port_regs.irq_stat, AHCIDevice),
1213         VMSTATE_UINT32(port_regs.irq_mask, AHCIDevice),
1214         VMSTATE_UINT32(port_regs.cmd, AHCIDevice),
1215         VMSTATE_UINT32(port_regs.tfdata, AHCIDevice),
1216         VMSTATE_UINT32(port_regs.sig, AHCIDevice),
1217         VMSTATE_UINT32(port_regs.scr_stat, AHCIDevice),
1218         VMSTATE_UINT32(port_regs.scr_ctl, AHCIDevice),
1219         VMSTATE_UINT32(port_regs.scr_err, AHCIDevice),
1220         VMSTATE_UINT32(port_regs.scr_act, AHCIDevice),
1221         VMSTATE_UINT32(port_regs.cmd_issue, AHCIDevice),
1222         VMSTATE_BOOL(done_atapi_packet, AHCIDevice),
1223         VMSTATE_INT32(busy_slot, AHCIDevice),
1224         VMSTATE_BOOL(init_d2h_sent, AHCIDevice),
1225         VMSTATE_END_OF_LIST()
1226     },
1227 };
1228 
1229 static int ahci_state_post_load(void *opaque, int version_id)
1230 {
1231     int i;
1232     struct AHCIDevice *ad;
1233     AHCIState *s = opaque;
1234 
1235     for (i = 0; i < s->ports; i++) {
1236         ad = &s->dev[i];
1237         AHCIPortRegs *pr = &ad->port_regs;
1238 
1239         map_page(&ad->lst,
1240                  ((uint64_t)pr->lst_addr_hi << 32) | pr->lst_addr, 1024);
1241         map_page(&ad->res_fis,
1242                  ((uint64_t)pr->fis_addr_hi << 32) | pr->fis_addr, 256);
1243         /*
1244          * All pending i/o should be flushed out on a migrate. However,
1245          * we might not have cleared the busy_slot since this is done
1246          * in a bh. Also, issue i/o against any slots that are pending.
1247          */
1248         if ((ad->busy_slot != -1) &&
1249             !(ad->port.ifs[0].status & (BUSY_STAT|DRQ_STAT))) {
1250             pr->cmd_issue &= ~(1 << ad->busy_slot);
1251             ad->busy_slot = -1;
1252         }
1253         check_cmd(s, i);
1254     }
1255 
1256     return 0;
1257 }
1258 
1259 const VMStateDescription vmstate_ahci = {
1260     .name = "ahci",
1261     .version_id = 1,
1262     .post_load = ahci_state_post_load,
1263     .fields = (VMStateField []) {
1264         VMSTATE_STRUCT_VARRAY_POINTER_INT32(dev, AHCIState, ports,
1265                                      vmstate_ahci_device, AHCIDevice),
1266         VMSTATE_UINT32(control_regs.cap, AHCIState),
1267         VMSTATE_UINT32(control_regs.ghc, AHCIState),
1268         VMSTATE_UINT32(control_regs.irqstatus, AHCIState),
1269         VMSTATE_UINT32(control_regs.impl, AHCIState),
1270         VMSTATE_UINT32(control_regs.version, AHCIState),
1271         VMSTATE_UINT32(idp_index, AHCIState),
1272         VMSTATE_INT32(ports, AHCIState),
1273         VMSTATE_END_OF_LIST()
1274     },
1275 };
1276 
1277 typedef struct SysbusAHCIState {
1278     SysBusDevice busdev;
1279     AHCIState ahci;
1280     uint32_t num_ports;
1281 } SysbusAHCIState;
1282 
1283 static const VMStateDescription vmstate_sysbus_ahci = {
1284     .name = "sysbus-ahci",
1285     .unmigratable = 1, /* Still buggy under I/O load */
1286     .fields = (VMStateField []) {
1287         VMSTATE_AHCI(ahci, AHCIPCIState),
1288         VMSTATE_END_OF_LIST()
1289     },
1290 };
1291 
1292 static void sysbus_ahci_reset(DeviceState *dev)
1293 {
1294     SysbusAHCIState *s = DO_UPCAST(SysbusAHCIState, busdev.qdev, dev);
1295 
1296     ahci_reset(&s->ahci);
1297 }
1298 
1299 static int sysbus_ahci_init(SysBusDevice *dev)
1300 {
1301     SysbusAHCIState *s = FROM_SYSBUS(SysbusAHCIState, dev);
1302     ahci_init(&s->ahci, &dev->qdev, NULL, s->num_ports);
1303 
1304     sysbus_init_mmio(dev, &s->ahci.mem);
1305     sysbus_init_irq(dev, &s->ahci.irq);
1306     return 0;
1307 }
1308 
1309 static Property sysbus_ahci_properties[] = {
1310     DEFINE_PROP_UINT32("num-ports", SysbusAHCIState, num_ports, 1),
1311     DEFINE_PROP_END_OF_LIST(),
1312 };
1313 
1314 static void sysbus_ahci_class_init(ObjectClass *klass, void *data)
1315 {
1316     SysBusDeviceClass *sbc = SYS_BUS_DEVICE_CLASS(klass);
1317     DeviceClass *dc = DEVICE_CLASS(klass);
1318 
1319     sbc->init = sysbus_ahci_init;
1320     dc->vmsd = &vmstate_sysbus_ahci;
1321     dc->props = sysbus_ahci_properties;
1322     dc->reset = sysbus_ahci_reset;
1323 }
1324 
1325 static const TypeInfo sysbus_ahci_info = {
1326     .name          = "sysbus-ahci",
1327     .parent        = TYPE_SYS_BUS_DEVICE,
1328     .instance_size = sizeof(SysbusAHCIState),
1329     .class_init    = sysbus_ahci_class_init,
1330 };
1331 
1332 static void sysbus_ahci_register_types(void)
1333 {
1334     type_register_static(&sysbus_ahci_info);
1335 }
1336 
1337 type_init(sysbus_ahci_register_types)
1338