xref: /openbmc/qemu/hw/ide/ahci.c (revision 09a274d8)
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 "qemu/osdep.h"
25 #include "hw/hw.h"
26 #include "hw/pci/msi.h"
27 #include "hw/pci/pci.h"
28 
29 #include "qemu/error-report.h"
30 #include "qemu/log.h"
31 #include "sysemu/block-backend.h"
32 #include "sysemu/dma.h"
33 #include "hw/ide/internal.h"
34 #include "hw/ide/pci.h"
35 #include "ahci_internal.h"
36 
37 #include "trace.h"
38 
39 static void check_cmd(AHCIState *s, int port);
40 static int handle_cmd(AHCIState *s, int port, uint8_t slot);
41 static void ahci_reset_port(AHCIState *s, int port);
42 static bool ahci_write_fis_d2h(AHCIDevice *ad);
43 static void ahci_init_d2h(AHCIDevice *ad);
44 static int ahci_dma_prepare_buf(IDEDMA *dma, int32_t limit);
45 static bool ahci_map_clb_address(AHCIDevice *ad);
46 static bool ahci_map_fis_address(AHCIDevice *ad);
47 static void ahci_unmap_clb_address(AHCIDevice *ad);
48 static void ahci_unmap_fis_address(AHCIDevice *ad);
49 
50 static const char *AHCIHostReg_lookup[AHCI_HOST_REG__COUNT] = {
51     [AHCI_HOST_REG_CAP]        = "CAP",
52     [AHCI_HOST_REG_CTL]        = "GHC",
53     [AHCI_HOST_REG_IRQ_STAT]   = "IS",
54     [AHCI_HOST_REG_PORTS_IMPL] = "PI",
55     [AHCI_HOST_REG_VERSION]    = "VS",
56     [AHCI_HOST_REG_CCC_CTL]    = "CCC_CTL",
57     [AHCI_HOST_REG_CCC_PORTS]  = "CCC_PORTS",
58     [AHCI_HOST_REG_EM_LOC]     = "EM_LOC",
59     [AHCI_HOST_REG_EM_CTL]     = "EM_CTL",
60     [AHCI_HOST_REG_CAP2]       = "CAP2",
61     [AHCI_HOST_REG_BOHC]       = "BOHC",
62 };
63 
64 static const char *AHCIPortReg_lookup[AHCI_PORT_REG__COUNT] = {
65     [AHCI_PORT_REG_LST_ADDR]    = "PxCLB",
66     [AHCI_PORT_REG_LST_ADDR_HI] = "PxCLBU",
67     [AHCI_PORT_REG_FIS_ADDR]    = "PxFB",
68     [AHCI_PORT_REG_FIS_ADDR_HI] = "PxFBU",
69     [AHCI_PORT_REG_IRQ_STAT]    = "PxIS",
70     [AHCI_PORT_REG_IRQ_MASK]    = "PXIE",
71     [AHCI_PORT_REG_CMD]         = "PxCMD",
72     [7]                         = "Reserved",
73     [AHCI_PORT_REG_TFDATA]      = "PxTFD",
74     [AHCI_PORT_REG_SIG]         = "PxSIG",
75     [AHCI_PORT_REG_SCR_STAT]    = "PxSSTS",
76     [AHCI_PORT_REG_SCR_CTL]     = "PxSCTL",
77     [AHCI_PORT_REG_SCR_ERR]     = "PxSERR",
78     [AHCI_PORT_REG_SCR_ACT]     = "PxSACT",
79     [AHCI_PORT_REG_CMD_ISSUE]   = "PxCI",
80     [AHCI_PORT_REG_SCR_NOTIF]   = "PxSNTF",
81     [AHCI_PORT_REG_FIS_CTL]     = "PxFBS",
82     [AHCI_PORT_REG_DEV_SLEEP]   = "PxDEVSLP",
83     [18 ... 27]                 = "Reserved",
84     [AHCI_PORT_REG_VENDOR_1 ...
85      AHCI_PORT_REG_VENDOR_4]    = "PxVS",
86 };
87 
88 static const char *AHCIPortIRQ_lookup[AHCI_PORT_IRQ__COUNT] = {
89     [AHCI_PORT_IRQ_BIT_DHRS] = "DHRS",
90     [AHCI_PORT_IRQ_BIT_PSS]  = "PSS",
91     [AHCI_PORT_IRQ_BIT_DSS]  = "DSS",
92     [AHCI_PORT_IRQ_BIT_SDBS] = "SDBS",
93     [AHCI_PORT_IRQ_BIT_UFS]  = "UFS",
94     [AHCI_PORT_IRQ_BIT_DPS]  = "DPS",
95     [AHCI_PORT_IRQ_BIT_PCS]  = "PCS",
96     [AHCI_PORT_IRQ_BIT_DMPS] = "DMPS",
97     [8 ... 21]               = "RESERVED",
98     [AHCI_PORT_IRQ_BIT_PRCS] = "PRCS",
99     [AHCI_PORT_IRQ_BIT_IPMS] = "IPMS",
100     [AHCI_PORT_IRQ_BIT_OFS]  = "OFS",
101     [25]                     = "RESERVED",
102     [AHCI_PORT_IRQ_BIT_INFS] = "INFS",
103     [AHCI_PORT_IRQ_BIT_IFS]  = "IFS",
104     [AHCI_PORT_IRQ_BIT_HBDS] = "HBDS",
105     [AHCI_PORT_IRQ_BIT_HBFS] = "HBFS",
106     [AHCI_PORT_IRQ_BIT_TFES] = "TFES",
107     [AHCI_PORT_IRQ_BIT_CPDS] = "CPDS"
108 };
109 
110 static uint32_t ahci_port_read(AHCIState *s, int port, int offset)
111 {
112     uint32_t val;
113     AHCIPortRegs *pr = &s->dev[port].port_regs;
114     enum AHCIPortReg regnum = offset / sizeof(uint32_t);
115     assert(regnum < (AHCI_PORT_ADDR_OFFSET_LEN / sizeof(uint32_t)));
116 
117     switch (regnum) {
118     case AHCI_PORT_REG_LST_ADDR:
119         val = pr->lst_addr;
120         break;
121     case AHCI_PORT_REG_LST_ADDR_HI:
122         val = pr->lst_addr_hi;
123         break;
124     case AHCI_PORT_REG_FIS_ADDR:
125         val = pr->fis_addr;
126         break;
127     case AHCI_PORT_REG_FIS_ADDR_HI:
128         val = pr->fis_addr_hi;
129         break;
130     case AHCI_PORT_REG_IRQ_STAT:
131         val = pr->irq_stat;
132         break;
133     case AHCI_PORT_REG_IRQ_MASK:
134         val = pr->irq_mask;
135         break;
136     case AHCI_PORT_REG_CMD:
137         val = pr->cmd;
138         break;
139     case AHCI_PORT_REG_TFDATA:
140         val = pr->tfdata;
141         break;
142     case AHCI_PORT_REG_SIG:
143         val = pr->sig;
144         break;
145     case AHCI_PORT_REG_SCR_STAT:
146         if (s->dev[port].port.ifs[0].blk) {
147             val = SATA_SCR_SSTATUS_DET_DEV_PRESENT_PHY_UP |
148                   SATA_SCR_SSTATUS_SPD_GEN1 | SATA_SCR_SSTATUS_IPM_ACTIVE;
149         } else {
150             val = SATA_SCR_SSTATUS_DET_NODEV;
151         }
152         break;
153     case AHCI_PORT_REG_SCR_CTL:
154         val = pr->scr_ctl;
155         break;
156     case AHCI_PORT_REG_SCR_ERR:
157         val = pr->scr_err;
158         break;
159     case AHCI_PORT_REG_SCR_ACT:
160         val = pr->scr_act;
161         break;
162     case AHCI_PORT_REG_CMD_ISSUE:
163         val = pr->cmd_issue;
164         break;
165     default:
166         trace_ahci_port_read_default(s, port, AHCIPortReg_lookup[regnum],
167                                      offset);
168         val = 0;
169     }
170 
171     trace_ahci_port_read(s, port, AHCIPortReg_lookup[regnum], offset, val);
172     return val;
173 }
174 
175 static void ahci_irq_raise(AHCIState *s)
176 {
177     DeviceState *dev_state = s->container;
178     PCIDevice *pci_dev = (PCIDevice *) object_dynamic_cast(OBJECT(dev_state),
179                                                            TYPE_PCI_DEVICE);
180 
181     trace_ahci_irq_raise(s);
182 
183     if (pci_dev && msi_enabled(pci_dev)) {
184         msi_notify(pci_dev, 0);
185     } else {
186         qemu_irq_raise(s->irq);
187     }
188 }
189 
190 static void ahci_irq_lower(AHCIState *s)
191 {
192     DeviceState *dev_state = s->container;
193     PCIDevice *pci_dev = (PCIDevice *) object_dynamic_cast(OBJECT(dev_state),
194                                                            TYPE_PCI_DEVICE);
195 
196     trace_ahci_irq_lower(s);
197 
198     if (!pci_dev || !msi_enabled(pci_dev)) {
199         qemu_irq_lower(s->irq);
200     }
201 }
202 
203 static void ahci_check_irq(AHCIState *s)
204 {
205     int i;
206     uint32_t old_irq = s->control_regs.irqstatus;
207 
208     s->control_regs.irqstatus = 0;
209     for (i = 0; i < s->ports; i++) {
210         AHCIPortRegs *pr = &s->dev[i].port_regs;
211         if (pr->irq_stat & pr->irq_mask) {
212             s->control_regs.irqstatus |= (1 << i);
213         }
214     }
215     trace_ahci_check_irq(s, old_irq, s->control_regs.irqstatus);
216     if (s->control_regs.irqstatus &&
217         (s->control_regs.ghc & HOST_CTL_IRQ_EN)) {
218             ahci_irq_raise(s);
219     } else {
220         ahci_irq_lower(s);
221     }
222 }
223 
224 static void ahci_trigger_irq(AHCIState *s, AHCIDevice *d,
225                              enum AHCIPortIRQ irqbit)
226 {
227     g_assert((unsigned)irqbit < 32);
228     uint32_t irq = 1U << irqbit;
229     uint32_t irqstat = d->port_regs.irq_stat | irq;
230 
231     trace_ahci_trigger_irq(s, d->port_no,
232                            AHCIPortIRQ_lookup[irqbit], irq,
233                            d->port_regs.irq_stat, irqstat,
234                            irqstat & d->port_regs.irq_mask);
235 
236     d->port_regs.irq_stat = irqstat;
237     ahci_check_irq(s);
238 }
239 
240 static void map_page(AddressSpace *as, uint8_t **ptr, uint64_t addr,
241                      uint32_t wanted)
242 {
243     hwaddr len = wanted;
244 
245     if (*ptr) {
246         dma_memory_unmap(as, *ptr, len, DMA_DIRECTION_FROM_DEVICE, len);
247     }
248 
249     *ptr = dma_memory_map(as, addr, &len, DMA_DIRECTION_FROM_DEVICE);
250     if (len < wanted) {
251         dma_memory_unmap(as, *ptr, len, DMA_DIRECTION_FROM_DEVICE, len);
252         *ptr = NULL;
253     }
254 }
255 
256 /**
257  * Check the cmd register to see if we should start or stop
258  * the DMA or FIS RX engines.
259  *
260  * @ad: Device to dis/engage.
261  *
262  * @return 0 on success, -1 on error.
263  */
264 static int ahci_cond_start_engines(AHCIDevice *ad)
265 {
266     AHCIPortRegs *pr = &ad->port_regs;
267     bool cmd_start = pr->cmd & PORT_CMD_START;
268     bool cmd_on    = pr->cmd & PORT_CMD_LIST_ON;
269     bool fis_start = pr->cmd & PORT_CMD_FIS_RX;
270     bool fis_on    = pr->cmd & PORT_CMD_FIS_ON;
271 
272     if (cmd_start && !cmd_on) {
273         if (!ahci_map_clb_address(ad)) {
274             pr->cmd &= ~PORT_CMD_START;
275             error_report("AHCI: Failed to start DMA engine: "
276                          "bad command list buffer address");
277             return -1;
278         }
279     } else if (!cmd_start && cmd_on) {
280         ahci_unmap_clb_address(ad);
281     }
282 
283     if (fis_start && !fis_on) {
284         if (!ahci_map_fis_address(ad)) {
285             pr->cmd &= ~PORT_CMD_FIS_RX;
286             error_report("AHCI: Failed to start FIS receive engine: "
287                          "bad FIS receive buffer address");
288             return -1;
289         }
290     } else if (!fis_start && fis_on) {
291         ahci_unmap_fis_address(ad);
292     }
293 
294     return 0;
295 }
296 
297 static void ahci_port_write(AHCIState *s, int port, int offset, uint32_t val)
298 {
299     AHCIPortRegs *pr = &s->dev[port].port_regs;
300     enum AHCIPortReg regnum = offset / sizeof(uint32_t);
301     assert(regnum < (AHCI_PORT_ADDR_OFFSET_LEN / sizeof(uint32_t)));
302     trace_ahci_port_write(s, port, AHCIPortReg_lookup[regnum], offset, val);
303 
304     switch (regnum) {
305     case AHCI_PORT_REG_LST_ADDR:
306         pr->lst_addr = val;
307         break;
308     case AHCI_PORT_REG_LST_ADDR_HI:
309         pr->lst_addr_hi = val;
310         break;
311     case AHCI_PORT_REG_FIS_ADDR:
312         pr->fis_addr = val;
313         break;
314     case AHCI_PORT_REG_FIS_ADDR_HI:
315         pr->fis_addr_hi = val;
316         break;
317     case AHCI_PORT_REG_IRQ_STAT:
318         pr->irq_stat &= ~val;
319         ahci_check_irq(s);
320         break;
321     case AHCI_PORT_REG_IRQ_MASK:
322         pr->irq_mask = val & 0xfdc000ff;
323         ahci_check_irq(s);
324         break;
325     case AHCI_PORT_REG_CMD:
326         /* Block any Read-only fields from being set;
327          * including LIST_ON and FIS_ON.
328          * The spec requires to set ICC bits to zero after the ICC change
329          * is done. We don't support ICC state changes, therefore always
330          * force the ICC bits to zero.
331          */
332         pr->cmd = (pr->cmd & PORT_CMD_RO_MASK) |
333             (val & ~(PORT_CMD_RO_MASK | PORT_CMD_ICC_MASK));
334 
335         /* Check FIS RX and CLB engines */
336         ahci_cond_start_engines(&s->dev[port]);
337 
338         /* XXX usually the FIS would be pending on the bus here and
339            issuing deferred until the OS enables FIS receival.
340            Instead, we only submit it once - which works in most
341            cases, but is a hack. */
342         if ((pr->cmd & PORT_CMD_FIS_ON) &&
343             !s->dev[port].init_d2h_sent) {
344             ahci_init_d2h(&s->dev[port]);
345         }
346 
347         check_cmd(s, port);
348         break;
349     case AHCI_PORT_REG_TFDATA:
350     case AHCI_PORT_REG_SIG:
351     case AHCI_PORT_REG_SCR_STAT:
352         /* Read Only */
353         break;
354     case AHCI_PORT_REG_SCR_CTL:
355         if (((pr->scr_ctl & AHCI_SCR_SCTL_DET) == 1) &&
356             ((val & AHCI_SCR_SCTL_DET) == 0)) {
357             ahci_reset_port(s, port);
358         }
359         pr->scr_ctl = val;
360         break;
361     case AHCI_PORT_REG_SCR_ERR:
362         pr->scr_err &= ~val;
363         break;
364     case AHCI_PORT_REG_SCR_ACT:
365         /* RW1 */
366         pr->scr_act |= val;
367         break;
368     case AHCI_PORT_REG_CMD_ISSUE:
369         pr->cmd_issue |= val;
370         check_cmd(s, port);
371         break;
372     default:
373         trace_ahci_port_write_unimpl(s, port, AHCIPortReg_lookup[regnum],
374                                      offset, val);
375         qemu_log_mask(LOG_UNIMP, "Attempted write to unimplemented register: "
376                       "AHCI port %d register %s, offset 0x%x: 0x%"PRIx32,
377                       port, AHCIPortReg_lookup[regnum], offset, val);
378         break;
379     }
380 }
381 
382 static uint64_t ahci_mem_read_32(void *opaque, hwaddr addr)
383 {
384     AHCIState *s = opaque;
385     uint32_t val = 0;
386 
387     if (addr < AHCI_GENERIC_HOST_CONTROL_REGS_MAX_ADDR) {
388         enum AHCIHostReg regnum = addr / 4;
389         assert(regnum < AHCI_HOST_REG__COUNT);
390 
391         switch (regnum) {
392         case AHCI_HOST_REG_CAP:
393             val = s->control_regs.cap;
394             break;
395         case AHCI_HOST_REG_CTL:
396             val = s->control_regs.ghc;
397             break;
398         case AHCI_HOST_REG_IRQ_STAT:
399             val = s->control_regs.irqstatus;
400             break;
401         case AHCI_HOST_REG_PORTS_IMPL:
402             val = s->control_regs.impl;
403             break;
404         case AHCI_HOST_REG_VERSION:
405             val = s->control_regs.version;
406             break;
407         default:
408             trace_ahci_mem_read_32_host_default(s, AHCIHostReg_lookup[regnum],
409                                                 addr);
410         }
411         trace_ahci_mem_read_32_host(s, AHCIHostReg_lookup[regnum], addr, val);
412     } else if ((addr >= AHCI_PORT_REGS_START_ADDR) &&
413                (addr < (AHCI_PORT_REGS_START_ADDR +
414                 (s->ports * AHCI_PORT_ADDR_OFFSET_LEN)))) {
415         val = ahci_port_read(s, (addr - AHCI_PORT_REGS_START_ADDR) >> 7,
416                              addr & AHCI_PORT_ADDR_OFFSET_MASK);
417     } else {
418         trace_ahci_mem_read_32_default(s, addr, val);
419     }
420 
421     trace_ahci_mem_read_32(s, addr, val);
422     return val;
423 }
424 
425 
426 /**
427  * AHCI 1.3 section 3 ("HBA Memory Registers")
428  * Support unaligned 8/16/32 bit reads, and 64 bit aligned reads.
429  * Caller is responsible for masking unwanted higher order bytes.
430  */
431 static uint64_t ahci_mem_read(void *opaque, hwaddr addr, unsigned size)
432 {
433     hwaddr aligned = addr & ~0x3;
434     int ofst = addr - aligned;
435     uint64_t lo = ahci_mem_read_32(opaque, aligned);
436     uint64_t hi;
437     uint64_t val;
438 
439     /* if < 8 byte read does not cross 4 byte boundary */
440     if (ofst + size <= 4) {
441         val = lo >> (ofst * 8);
442     } else {
443         g_assert(size > 1);
444 
445         /* If the 64bit read is unaligned, we will produce undefined
446          * results. AHCI does not support unaligned 64bit reads. */
447         hi = ahci_mem_read_32(opaque, aligned + 4);
448         val = (hi << 32 | lo) >> (ofst * 8);
449     }
450 
451     trace_ahci_mem_read(opaque, size, addr, val);
452     return val;
453 }
454 
455 
456 static void ahci_mem_write(void *opaque, hwaddr addr,
457                            uint64_t val, unsigned size)
458 {
459     AHCIState *s = opaque;
460 
461     trace_ahci_mem_write(s, size, addr, val);
462 
463     /* Only aligned reads are allowed on AHCI */
464     if (addr & 3) {
465         fprintf(stderr, "ahci: Mis-aligned write to addr 0x"
466                 TARGET_FMT_plx "\n", addr);
467         return;
468     }
469 
470     if (addr < AHCI_GENERIC_HOST_CONTROL_REGS_MAX_ADDR) {
471         enum AHCIHostReg regnum = addr / 4;
472         assert(regnum < AHCI_HOST_REG__COUNT);
473 
474         switch (regnum) {
475         case AHCI_HOST_REG_CAP: /* R/WO, RO */
476             /* FIXME handle R/WO */
477             break;
478         case AHCI_HOST_REG_CTL: /* R/W */
479             if (val & HOST_CTL_RESET) {
480                 ahci_reset(s);
481             } else {
482                 s->control_regs.ghc = (val & 0x3) | HOST_CTL_AHCI_EN;
483                 ahci_check_irq(s);
484             }
485             break;
486         case AHCI_HOST_REG_IRQ_STAT: /* R/WC, RO */
487             s->control_regs.irqstatus &= ~val;
488             ahci_check_irq(s);
489             break;
490         case AHCI_HOST_REG_PORTS_IMPL: /* R/WO, RO */
491             /* FIXME handle R/WO */
492             break;
493         case AHCI_HOST_REG_VERSION: /* RO */
494             /* FIXME report write? */
495             break;
496         default:
497             qemu_log_mask(LOG_UNIMP,
498                           "Attempted write to unimplemented register: "
499                           "AHCI host register %s, "
500                           "offset 0x%"PRIx64": 0x%"PRIx64,
501                           AHCIHostReg_lookup[regnum], addr, val);
502             trace_ahci_mem_write_host_unimpl(s, size,
503                                              AHCIHostReg_lookup[regnum], addr);
504         }
505         trace_ahci_mem_write_host(s, size, AHCIHostReg_lookup[regnum],
506                                      addr, val);
507     } else if ((addr >= AHCI_PORT_REGS_START_ADDR) &&
508                (addr < (AHCI_PORT_REGS_START_ADDR +
509                         (s->ports * AHCI_PORT_ADDR_OFFSET_LEN)))) {
510         ahci_port_write(s, (addr - AHCI_PORT_REGS_START_ADDR) >> 7,
511                         addr & AHCI_PORT_ADDR_OFFSET_MASK, val);
512     } else {
513         qemu_log_mask(LOG_UNIMP, "Attempted write to unimplemented register: "
514                       "AHCI global register at offset 0x%"PRIx64": 0x%"PRIx64,
515                       addr, val);
516         trace_ahci_mem_write_unimpl(s, size, addr, val);
517     }
518 }
519 
520 static const MemoryRegionOps ahci_mem_ops = {
521     .read = ahci_mem_read,
522     .write = ahci_mem_write,
523     .endianness = DEVICE_LITTLE_ENDIAN,
524 };
525 
526 static uint64_t ahci_idp_read(void *opaque, hwaddr addr,
527                               unsigned size)
528 {
529     AHCIState *s = opaque;
530 
531     if (addr == s->idp_offset) {
532         /* index register */
533         return s->idp_index;
534     } else if (addr == s->idp_offset + 4) {
535         /* data register - do memory read at location selected by index */
536         return ahci_mem_read(opaque, s->idp_index, size);
537     } else {
538         return 0;
539     }
540 }
541 
542 static void ahci_idp_write(void *opaque, hwaddr addr,
543                            uint64_t val, unsigned size)
544 {
545     AHCIState *s = opaque;
546 
547     if (addr == s->idp_offset) {
548         /* index register - mask off reserved bits */
549         s->idp_index = (uint32_t)val & ((AHCI_MEM_BAR_SIZE - 1) & ~3);
550     } else if (addr == s->idp_offset + 4) {
551         /* data register - do memory write at location selected by index */
552         ahci_mem_write(opaque, s->idp_index, val, size);
553     }
554 }
555 
556 static const MemoryRegionOps ahci_idp_ops = {
557     .read = ahci_idp_read,
558     .write = ahci_idp_write,
559     .endianness = DEVICE_LITTLE_ENDIAN,
560 };
561 
562 
563 static void ahci_reg_init(AHCIState *s)
564 {
565     int i;
566 
567     s->control_regs.cap = (s->ports - 1) |
568                           (AHCI_NUM_COMMAND_SLOTS << 8) |
569                           (AHCI_SUPPORTED_SPEED_GEN1 << AHCI_SUPPORTED_SPEED) |
570                           HOST_CAP_NCQ | HOST_CAP_AHCI | HOST_CAP_64;
571 
572     s->control_regs.impl = (1 << s->ports) - 1;
573 
574     s->control_regs.version = AHCI_VERSION_1_0;
575 
576     for (i = 0; i < s->ports; i++) {
577         s->dev[i].port_state = STATE_RUN;
578     }
579 }
580 
581 static void check_cmd(AHCIState *s, int port)
582 {
583     AHCIPortRegs *pr = &s->dev[port].port_regs;
584     uint8_t slot;
585 
586     if ((pr->cmd & PORT_CMD_START) && pr->cmd_issue) {
587         for (slot = 0; (slot < 32) && pr->cmd_issue; slot++) {
588             if ((pr->cmd_issue & (1U << slot)) &&
589                 !handle_cmd(s, port, slot)) {
590                 pr->cmd_issue &= ~(1U << slot);
591             }
592         }
593     }
594 }
595 
596 static void ahci_check_cmd_bh(void *opaque)
597 {
598     AHCIDevice *ad = opaque;
599 
600     qemu_bh_delete(ad->check_bh);
601     ad->check_bh = NULL;
602 
603     check_cmd(ad->hba, ad->port_no);
604 }
605 
606 static void ahci_init_d2h(AHCIDevice *ad)
607 {
608     IDEState *ide_state = &ad->port.ifs[0];
609     AHCIPortRegs *pr = &ad->port_regs;
610 
611     if (ad->init_d2h_sent) {
612         return;
613     }
614 
615     if (ahci_write_fis_d2h(ad)) {
616         ad->init_d2h_sent = true;
617         /* We're emulating receiving the first Reg H2D Fis from the device;
618          * Update the SIG register, but otherwise proceed as normal. */
619         pr->sig = ((uint32_t)ide_state->hcyl << 24) |
620             (ide_state->lcyl << 16) |
621             (ide_state->sector << 8) |
622             (ide_state->nsector & 0xFF);
623     }
624 }
625 
626 static void ahci_set_signature(AHCIDevice *ad, uint32_t sig)
627 {
628     IDEState *s = &ad->port.ifs[0];
629     s->hcyl = sig >> 24 & 0xFF;
630     s->lcyl = sig >> 16 & 0xFF;
631     s->sector = sig >> 8 & 0xFF;
632     s->nsector = sig & 0xFF;
633 
634     trace_ahci_set_signature(ad->hba, ad->port_no, s->nsector, s->sector,
635                              s->lcyl, s->hcyl, sig);
636 }
637 
638 static void ahci_reset_port(AHCIState *s, int port)
639 {
640     AHCIDevice *d = &s->dev[port];
641     AHCIPortRegs *pr = &d->port_regs;
642     IDEState *ide_state = &d->port.ifs[0];
643     int i;
644 
645     trace_ahci_reset_port(s, port);
646 
647     ide_bus_reset(&d->port);
648     ide_state->ncq_queues = AHCI_MAX_CMDS;
649 
650     pr->scr_stat = 0;
651     pr->scr_err = 0;
652     pr->scr_act = 0;
653     pr->tfdata = 0x7F;
654     pr->sig = 0xFFFFFFFF;
655     d->busy_slot = -1;
656     d->init_d2h_sent = false;
657 
658     ide_state = &s->dev[port].port.ifs[0];
659     if (!ide_state->blk) {
660         return;
661     }
662 
663     /* reset ncq queue */
664     for (i = 0; i < AHCI_MAX_CMDS; i++) {
665         NCQTransferState *ncq_tfs = &s->dev[port].ncq_tfs[i];
666         ncq_tfs->halt = false;
667         if (!ncq_tfs->used) {
668             continue;
669         }
670 
671         if (ncq_tfs->aiocb) {
672             blk_aio_cancel(ncq_tfs->aiocb);
673             ncq_tfs->aiocb = NULL;
674         }
675 
676         /* Maybe we just finished the request thanks to blk_aio_cancel() */
677         if (!ncq_tfs->used) {
678             continue;
679         }
680 
681         qemu_sglist_destroy(&ncq_tfs->sglist);
682         ncq_tfs->used = 0;
683     }
684 
685     s->dev[port].port_state = STATE_RUN;
686     if (ide_state->drive_kind == IDE_CD) {
687         ahci_set_signature(d, SATA_SIGNATURE_CDROM);\
688         ide_state->status = SEEK_STAT | WRERR_STAT | READY_STAT;
689     } else {
690         ahci_set_signature(d, SATA_SIGNATURE_DISK);
691         ide_state->status = SEEK_STAT | WRERR_STAT;
692     }
693 
694     ide_state->error = 1;
695     ahci_init_d2h(d);
696 }
697 
698 /* Buffer pretty output based on a raw FIS structure. */
699 static char *ahci_pretty_buffer_fis(uint8_t *fis, int cmd_len)
700 {
701     int i;
702     GString *s = g_string_new("FIS:");
703 
704     for (i = 0; i < cmd_len; i++) {
705         if ((i & 0xf) == 0) {
706             g_string_append_printf(s, "\n0x%02x: ", i);
707         }
708         g_string_append_printf(s, "%02x ", fis[i]);
709     }
710     g_string_append_c(s, '\n');
711 
712     return g_string_free(s, FALSE);
713 }
714 
715 static bool ahci_map_fis_address(AHCIDevice *ad)
716 {
717     AHCIPortRegs *pr = &ad->port_regs;
718     map_page(ad->hba->as, &ad->res_fis,
719              ((uint64_t)pr->fis_addr_hi << 32) | pr->fis_addr, 256);
720     if (ad->res_fis != NULL) {
721         pr->cmd |= PORT_CMD_FIS_ON;
722         return true;
723     }
724 
725     pr->cmd &= ~PORT_CMD_FIS_ON;
726     return false;
727 }
728 
729 static void ahci_unmap_fis_address(AHCIDevice *ad)
730 {
731     if (ad->res_fis == NULL) {
732         trace_ahci_unmap_fis_address_null(ad->hba, ad->port_no);
733         return;
734     }
735     ad->port_regs.cmd &= ~PORT_CMD_FIS_ON;
736     dma_memory_unmap(ad->hba->as, ad->res_fis, 256,
737                      DMA_DIRECTION_FROM_DEVICE, 256);
738     ad->res_fis = NULL;
739 }
740 
741 static bool ahci_map_clb_address(AHCIDevice *ad)
742 {
743     AHCIPortRegs *pr = &ad->port_regs;
744     ad->cur_cmd = NULL;
745     map_page(ad->hba->as, &ad->lst,
746              ((uint64_t)pr->lst_addr_hi << 32) | pr->lst_addr, 1024);
747     if (ad->lst != NULL) {
748         pr->cmd |= PORT_CMD_LIST_ON;
749         return true;
750     }
751 
752     pr->cmd &= ~PORT_CMD_LIST_ON;
753     return false;
754 }
755 
756 static void ahci_unmap_clb_address(AHCIDevice *ad)
757 {
758     if (ad->lst == NULL) {
759         trace_ahci_unmap_clb_address_null(ad->hba, ad->port_no);
760         return;
761     }
762     ad->port_regs.cmd &= ~PORT_CMD_LIST_ON;
763     dma_memory_unmap(ad->hba->as, ad->lst, 1024,
764                      DMA_DIRECTION_FROM_DEVICE, 1024);
765     ad->lst = NULL;
766 }
767 
768 static void ahci_write_fis_sdb(AHCIState *s, NCQTransferState *ncq_tfs)
769 {
770     AHCIDevice *ad = ncq_tfs->drive;
771     AHCIPortRegs *pr = &ad->port_regs;
772     IDEState *ide_state;
773     SDBFIS *sdb_fis;
774 
775     if (!ad->res_fis ||
776         !(pr->cmd & PORT_CMD_FIS_RX)) {
777         return;
778     }
779 
780     sdb_fis = (SDBFIS *)&ad->res_fis[RES_FIS_SDBFIS];
781     ide_state = &ad->port.ifs[0];
782 
783     sdb_fis->type = SATA_FIS_TYPE_SDB;
784     /* Interrupt pending & Notification bit */
785     sdb_fis->flags = 0x40; /* Interrupt bit, always 1 for NCQ */
786     sdb_fis->status = ide_state->status & 0x77;
787     sdb_fis->error = ide_state->error;
788     /* update SAct field in SDB_FIS */
789     sdb_fis->payload = cpu_to_le32(ad->finished);
790 
791     /* Update shadow registers (except BSY 0x80 and DRQ 0x08) */
792     pr->tfdata = (ad->port.ifs[0].error << 8) |
793         (ad->port.ifs[0].status & 0x77) |
794         (pr->tfdata & 0x88);
795     pr->scr_act &= ~ad->finished;
796     ad->finished = 0;
797 
798     /* Trigger IRQ if interrupt bit is set (which currently, it always is) */
799     if (sdb_fis->flags & 0x40) {
800         ahci_trigger_irq(s, ad, AHCI_PORT_IRQ_BIT_SDBS);
801     }
802 }
803 
804 static void ahci_write_fis_pio(AHCIDevice *ad, uint16_t len, bool pio_fis_i)
805 {
806     AHCIPortRegs *pr = &ad->port_regs;
807     uint8_t *pio_fis;
808     IDEState *s = &ad->port.ifs[0];
809 
810     if (!ad->res_fis || !(pr->cmd & PORT_CMD_FIS_RX)) {
811         return;
812     }
813 
814     pio_fis = &ad->res_fis[RES_FIS_PSFIS];
815 
816     pio_fis[0] = SATA_FIS_TYPE_PIO_SETUP;
817     pio_fis[1] = (pio_fis_i ? (1 << 6) : 0);
818     pio_fis[2] = s->status;
819     pio_fis[3] = s->error;
820 
821     pio_fis[4] = s->sector;
822     pio_fis[5] = s->lcyl;
823     pio_fis[6] = s->hcyl;
824     pio_fis[7] = s->select;
825     pio_fis[8] = s->hob_sector;
826     pio_fis[9] = s->hob_lcyl;
827     pio_fis[10] = s->hob_hcyl;
828     pio_fis[11] = 0;
829     pio_fis[12] = s->nsector & 0xFF;
830     pio_fis[13] = (s->nsector >> 8) & 0xFF;
831     pio_fis[14] = 0;
832     pio_fis[15] = s->status;
833     pio_fis[16] = len & 255;
834     pio_fis[17] = len >> 8;
835     pio_fis[18] = 0;
836     pio_fis[19] = 0;
837 
838     /* Update shadow registers: */
839     pr->tfdata = (ad->port.ifs[0].error << 8) |
840         ad->port.ifs[0].status;
841 
842     if (pio_fis[2] & ERR_STAT) {
843         ahci_trigger_irq(ad->hba, ad, AHCI_PORT_IRQ_BIT_TFES);
844     }
845 }
846 
847 static bool ahci_write_fis_d2h(AHCIDevice *ad)
848 {
849     AHCIPortRegs *pr = &ad->port_regs;
850     uint8_t *d2h_fis;
851     int i;
852     IDEState *s = &ad->port.ifs[0];
853 
854     if (!ad->res_fis || !(pr->cmd & PORT_CMD_FIS_RX)) {
855         return false;
856     }
857 
858     d2h_fis = &ad->res_fis[RES_FIS_RFIS];
859 
860     d2h_fis[0] = SATA_FIS_TYPE_REGISTER_D2H;
861     d2h_fis[1] = (1 << 6); /* interrupt bit */
862     d2h_fis[2] = s->status;
863     d2h_fis[3] = s->error;
864 
865     d2h_fis[4] = s->sector;
866     d2h_fis[5] = s->lcyl;
867     d2h_fis[6] = s->hcyl;
868     d2h_fis[7] = s->select;
869     d2h_fis[8] = s->hob_sector;
870     d2h_fis[9] = s->hob_lcyl;
871     d2h_fis[10] = s->hob_hcyl;
872     d2h_fis[11] = 0;
873     d2h_fis[12] = s->nsector & 0xFF;
874     d2h_fis[13] = (s->nsector >> 8) & 0xFF;
875     for (i = 14; i < 20; i++) {
876         d2h_fis[i] = 0;
877     }
878 
879     /* Update shadow registers: */
880     pr->tfdata = (ad->port.ifs[0].error << 8) |
881         ad->port.ifs[0].status;
882 
883     if (d2h_fis[2] & ERR_STAT) {
884         ahci_trigger_irq(ad->hba, ad, AHCI_PORT_IRQ_BIT_TFES);
885     }
886 
887     ahci_trigger_irq(ad->hba, ad, AHCI_PORT_IRQ_BIT_DHRS);
888     return true;
889 }
890 
891 static int prdt_tbl_entry_size(const AHCI_SG *tbl)
892 {
893     /* flags_size is zero-based */
894     return (le32_to_cpu(tbl->flags_size) & AHCI_PRDT_SIZE_MASK) + 1;
895 }
896 
897 /**
898  * Fetch entries in a guest-provided PRDT and convert it into a QEMU SGlist.
899  * @ad: The AHCIDevice for whom we are building the SGList.
900  * @sglist: The SGList target to add PRD entries to.
901  * @cmd: The AHCI Command Header that describes where the PRDT is.
902  * @limit: The remaining size of the S/ATA transaction, in bytes.
903  * @offset: The number of bytes already transferred, in bytes.
904  *
905  * The AHCI PRDT can describe up to 256GiB. S/ATA only support transactions of
906  * up to 32MiB as of ATA8-ACS3 rev 1b, assuming a 512 byte sector size. We stop
907  * building the sglist from the PRDT as soon as we hit @limit bytes,
908  * which is <= INT32_MAX/2GiB.
909  */
910 static int ahci_populate_sglist(AHCIDevice *ad, QEMUSGList *sglist,
911                                 AHCICmdHdr *cmd, int64_t limit, uint64_t offset)
912 {
913     uint16_t opts = le16_to_cpu(cmd->opts);
914     uint16_t prdtl = le16_to_cpu(cmd->prdtl);
915     uint64_t cfis_addr = le64_to_cpu(cmd->tbl_addr);
916     uint64_t prdt_addr = cfis_addr + 0x80;
917     dma_addr_t prdt_len = (prdtl * sizeof(AHCI_SG));
918     dma_addr_t real_prdt_len = prdt_len;
919     uint8_t *prdt;
920     int i;
921     int r = 0;
922     uint64_t sum = 0;
923     int off_idx = -1;
924     int64_t off_pos = -1;
925     int tbl_entry_size;
926     IDEBus *bus = &ad->port;
927     BusState *qbus = BUS(bus);
928 
929     trace_ahci_populate_sglist(ad->hba, ad->port_no);
930 
931     if (!prdtl) {
932         trace_ahci_populate_sglist_no_prdtl(ad->hba, ad->port_no, opts);
933         return -1;
934     }
935 
936     /* map PRDT */
937     if (!(prdt = dma_memory_map(ad->hba->as, prdt_addr, &prdt_len,
938                                 DMA_DIRECTION_TO_DEVICE))){
939         trace_ahci_populate_sglist_no_map(ad->hba, ad->port_no);
940         return -1;
941     }
942 
943     if (prdt_len < real_prdt_len) {
944         trace_ahci_populate_sglist_short_map(ad->hba, ad->port_no);
945         r = -1;
946         goto out;
947     }
948 
949     /* Get entries in the PRDT, init a qemu sglist accordingly */
950     if (prdtl > 0) {
951         AHCI_SG *tbl = (AHCI_SG *)prdt;
952         sum = 0;
953         for (i = 0; i < prdtl; i++) {
954             tbl_entry_size = prdt_tbl_entry_size(&tbl[i]);
955             if (offset < (sum + tbl_entry_size)) {
956                 off_idx = i;
957                 off_pos = offset - sum;
958                 break;
959             }
960             sum += tbl_entry_size;
961         }
962         if ((off_idx == -1) || (off_pos < 0) || (off_pos > tbl_entry_size)) {
963             trace_ahci_populate_sglist_bad_offset(ad->hba, ad->port_no,
964                                                   off_idx, off_pos);
965             r = -1;
966             goto out;
967         }
968 
969         qemu_sglist_init(sglist, qbus->parent, (prdtl - off_idx),
970                          ad->hba->as);
971         qemu_sglist_add(sglist, le64_to_cpu(tbl[off_idx].addr) + off_pos,
972                         MIN(prdt_tbl_entry_size(&tbl[off_idx]) - off_pos,
973                             limit));
974 
975         for (i = off_idx + 1; i < prdtl && sglist->size < limit; i++) {
976             qemu_sglist_add(sglist, le64_to_cpu(tbl[i].addr),
977                             MIN(prdt_tbl_entry_size(&tbl[i]),
978                                 limit - sglist->size));
979         }
980     }
981 
982 out:
983     dma_memory_unmap(ad->hba->as, prdt, prdt_len,
984                      DMA_DIRECTION_TO_DEVICE, prdt_len);
985     return r;
986 }
987 
988 static void ncq_err(NCQTransferState *ncq_tfs)
989 {
990     IDEState *ide_state = &ncq_tfs->drive->port.ifs[0];
991 
992     ide_state->error = ABRT_ERR;
993     ide_state->status = READY_STAT | ERR_STAT;
994     ncq_tfs->drive->port_regs.scr_err |= (1 << ncq_tfs->tag);
995     qemu_sglist_destroy(&ncq_tfs->sglist);
996     ncq_tfs->used = 0;
997 }
998 
999 static void ncq_finish(NCQTransferState *ncq_tfs)
1000 {
1001     /* If we didn't error out, set our finished bit. Errored commands
1002      * do not get a bit set for the SDB FIS ACT register, nor do they
1003      * clear the outstanding bit in scr_act (PxSACT). */
1004     if (!(ncq_tfs->drive->port_regs.scr_err & (1 << ncq_tfs->tag))) {
1005         ncq_tfs->drive->finished |= (1 << ncq_tfs->tag);
1006     }
1007 
1008     ahci_write_fis_sdb(ncq_tfs->drive->hba, ncq_tfs);
1009 
1010     trace_ncq_finish(ncq_tfs->drive->hba, ncq_tfs->drive->port_no,
1011                      ncq_tfs->tag);
1012 
1013     block_acct_done(blk_get_stats(ncq_tfs->drive->port.ifs[0].blk),
1014                     &ncq_tfs->acct);
1015     qemu_sglist_destroy(&ncq_tfs->sglist);
1016     ncq_tfs->used = 0;
1017 }
1018 
1019 static void ncq_cb(void *opaque, int ret)
1020 {
1021     NCQTransferState *ncq_tfs = (NCQTransferState *)opaque;
1022     IDEState *ide_state = &ncq_tfs->drive->port.ifs[0];
1023 
1024     ncq_tfs->aiocb = NULL;
1025     if (ret == -ECANCELED) {
1026         return;
1027     }
1028 
1029     if (ret < 0) {
1030         bool is_read = ncq_tfs->cmd == READ_FPDMA_QUEUED;
1031         BlockErrorAction action = blk_get_error_action(ide_state->blk,
1032                                                        is_read, -ret);
1033         if (action == BLOCK_ERROR_ACTION_STOP) {
1034             ncq_tfs->halt = true;
1035             ide_state->bus->error_status = IDE_RETRY_HBA;
1036         } else if (action == BLOCK_ERROR_ACTION_REPORT) {
1037             ncq_err(ncq_tfs);
1038         }
1039         blk_error_action(ide_state->blk, action, is_read, -ret);
1040     } else {
1041         ide_state->status = READY_STAT | SEEK_STAT;
1042     }
1043 
1044     if (!ncq_tfs->halt) {
1045         ncq_finish(ncq_tfs);
1046     }
1047 }
1048 
1049 static int is_ncq(uint8_t ata_cmd)
1050 {
1051     /* Based on SATA 3.2 section 13.6.3.2 */
1052     switch (ata_cmd) {
1053     case READ_FPDMA_QUEUED:
1054     case WRITE_FPDMA_QUEUED:
1055     case NCQ_NON_DATA:
1056     case RECEIVE_FPDMA_QUEUED:
1057     case SEND_FPDMA_QUEUED:
1058         return 1;
1059     default:
1060         return 0;
1061     }
1062 }
1063 
1064 static void execute_ncq_command(NCQTransferState *ncq_tfs)
1065 {
1066     AHCIDevice *ad = ncq_tfs->drive;
1067     IDEState *ide_state = &ad->port.ifs[0];
1068     int port = ad->port_no;
1069 
1070     g_assert(is_ncq(ncq_tfs->cmd));
1071     ncq_tfs->halt = false;
1072 
1073     switch (ncq_tfs->cmd) {
1074     case READ_FPDMA_QUEUED:
1075         trace_execute_ncq_command_read(ad->hba, port, ncq_tfs->tag,
1076                                        ncq_tfs->sector_count, ncq_tfs->lba);
1077         dma_acct_start(ide_state->blk, &ncq_tfs->acct,
1078                        &ncq_tfs->sglist, BLOCK_ACCT_READ);
1079         ncq_tfs->aiocb = dma_blk_read(ide_state->blk, &ncq_tfs->sglist,
1080                                       ncq_tfs->lba << BDRV_SECTOR_BITS,
1081                                       BDRV_SECTOR_SIZE,
1082                                       ncq_cb, ncq_tfs);
1083         break;
1084     case WRITE_FPDMA_QUEUED:
1085         trace_execute_ncq_command_read(ad->hba, port, ncq_tfs->tag,
1086                                        ncq_tfs->sector_count, ncq_tfs->lba);
1087         dma_acct_start(ide_state->blk, &ncq_tfs->acct,
1088                        &ncq_tfs->sglist, BLOCK_ACCT_WRITE);
1089         ncq_tfs->aiocb = dma_blk_write(ide_state->blk, &ncq_tfs->sglist,
1090                                        ncq_tfs->lba << BDRV_SECTOR_BITS,
1091                                        BDRV_SECTOR_SIZE,
1092                                        ncq_cb, ncq_tfs);
1093         break;
1094     default:
1095         trace_execute_ncq_command_unsup(ad->hba, port,
1096                                         ncq_tfs->tag, ncq_tfs->cmd);
1097         ncq_err(ncq_tfs);
1098     }
1099 }
1100 
1101 
1102 static void process_ncq_command(AHCIState *s, int port, uint8_t *cmd_fis,
1103                                 uint8_t slot)
1104 {
1105     AHCIDevice *ad = &s->dev[port];
1106     NCQFrame *ncq_fis = (NCQFrame*)cmd_fis;
1107     uint8_t tag = ncq_fis->tag >> 3;
1108     NCQTransferState *ncq_tfs = &ad->ncq_tfs[tag];
1109     size_t size;
1110 
1111     g_assert(is_ncq(ncq_fis->command));
1112     if (ncq_tfs->used) {
1113         /* error - already in use */
1114         fprintf(stderr, "%s: tag %d already used\n", __func__, tag);
1115         return;
1116     }
1117 
1118     ncq_tfs->used = 1;
1119     ncq_tfs->drive = ad;
1120     ncq_tfs->slot = slot;
1121     ncq_tfs->cmdh = &((AHCICmdHdr *)ad->lst)[slot];
1122     ncq_tfs->cmd = ncq_fis->command;
1123     ncq_tfs->lba = ((uint64_t)ncq_fis->lba5 << 40) |
1124                    ((uint64_t)ncq_fis->lba4 << 32) |
1125                    ((uint64_t)ncq_fis->lba3 << 24) |
1126                    ((uint64_t)ncq_fis->lba2 << 16) |
1127                    ((uint64_t)ncq_fis->lba1 << 8) |
1128                    (uint64_t)ncq_fis->lba0;
1129     ncq_tfs->tag = tag;
1130 
1131     /* Sanity-check the NCQ packet */
1132     if (tag != slot) {
1133         trace_process_ncq_command_mismatch(s, port, tag, slot);
1134     }
1135 
1136     if (ncq_fis->aux0 || ncq_fis->aux1 || ncq_fis->aux2 || ncq_fis->aux3) {
1137         trace_process_ncq_command_aux(s, port, tag);
1138     }
1139     if (ncq_fis->prio || ncq_fis->icc) {
1140         trace_process_ncq_command_prioicc(s, port, tag);
1141     }
1142     if (ncq_fis->fua & NCQ_FIS_FUA_MASK) {
1143         trace_process_ncq_command_fua(s, port, tag);
1144     }
1145     if (ncq_fis->tag & NCQ_FIS_RARC_MASK) {
1146         trace_process_ncq_command_rarc(s, port, tag);
1147     }
1148 
1149     ncq_tfs->sector_count = ((ncq_fis->sector_count_high << 8) |
1150                              ncq_fis->sector_count_low);
1151     if (!ncq_tfs->sector_count) {
1152         ncq_tfs->sector_count = 0x10000;
1153     }
1154     size = ncq_tfs->sector_count * 512;
1155     ahci_populate_sglist(ad, &ncq_tfs->sglist, ncq_tfs->cmdh, size, 0);
1156 
1157     if (ncq_tfs->sglist.size < size) {
1158         error_report("ahci: PRDT length for NCQ command (0x%zx) "
1159                      "is smaller than the requested size (0x%zx)",
1160                      ncq_tfs->sglist.size, size);
1161         ncq_err(ncq_tfs);
1162         ahci_trigger_irq(ad->hba, ad, AHCI_PORT_IRQ_BIT_OFS);
1163         return;
1164     } else if (ncq_tfs->sglist.size != size) {
1165         trace_process_ncq_command_large(s, port, tag,
1166                                         ncq_tfs->sglist.size, size);
1167     }
1168 
1169     trace_process_ncq_command(s, port, tag,
1170                               ncq_fis->command,
1171                               ncq_tfs->lba,
1172                               ncq_tfs->lba + ncq_tfs->sector_count - 1);
1173     execute_ncq_command(ncq_tfs);
1174 }
1175 
1176 static AHCICmdHdr *get_cmd_header(AHCIState *s, uint8_t port, uint8_t slot)
1177 {
1178     if (port >= s->ports || slot >= AHCI_MAX_CMDS) {
1179         return NULL;
1180     }
1181 
1182     return s->dev[port].lst ? &((AHCICmdHdr *)s->dev[port].lst)[slot] : NULL;
1183 }
1184 
1185 static void handle_reg_h2d_fis(AHCIState *s, int port,
1186                                uint8_t slot, uint8_t *cmd_fis)
1187 {
1188     IDEState *ide_state = &s->dev[port].port.ifs[0];
1189     AHCICmdHdr *cmd = get_cmd_header(s, port, slot);
1190     uint16_t opts = le16_to_cpu(cmd->opts);
1191 
1192     if (cmd_fis[1] & 0x0F) {
1193         trace_handle_reg_h2d_fis_pmp(s, port, cmd_fis[1],
1194                                      cmd_fis[2], cmd_fis[3]);
1195         return;
1196     }
1197 
1198     if (cmd_fis[1] & 0x70) {
1199         trace_handle_reg_h2d_fis_res(s, port, cmd_fis[1],
1200                                      cmd_fis[2], cmd_fis[3]);
1201         return;
1202     }
1203 
1204     if (!(cmd_fis[1] & SATA_FIS_REG_H2D_UPDATE_COMMAND_REGISTER)) {
1205         switch (s->dev[port].port_state) {
1206         case STATE_RUN:
1207             if (cmd_fis[15] & ATA_SRST) {
1208                 s->dev[port].port_state = STATE_RESET;
1209             }
1210             break;
1211         case STATE_RESET:
1212             if (!(cmd_fis[15] & ATA_SRST)) {
1213                 ahci_reset_port(s, port);
1214             }
1215             break;
1216         }
1217         return;
1218     }
1219 
1220     /* Check for NCQ command */
1221     if (is_ncq(cmd_fis[2])) {
1222         process_ncq_command(s, port, cmd_fis, slot);
1223         return;
1224     }
1225 
1226     /* Decompose the FIS:
1227      * AHCI does not interpret FIS packets, it only forwards them.
1228      * SATA 1.0 describes how to decode LBA28 and CHS FIS packets.
1229      * Later specifications, e.g, SATA 3.2, describe LBA48 FIS packets.
1230      *
1231      * ATA4 describes sector number for LBA28/CHS commands.
1232      * ATA6 describes sector number for LBA48 commands.
1233      * ATA8 deprecates CHS fully, describing only LBA28/48.
1234      *
1235      * We dutifully convert the FIS into IDE registers, and allow the
1236      * core layer to interpret them as needed. */
1237     ide_state->feature = cmd_fis[3];
1238     ide_state->sector = cmd_fis[4];      /* LBA 7:0 */
1239     ide_state->lcyl = cmd_fis[5];        /* LBA 15:8  */
1240     ide_state->hcyl = cmd_fis[6];        /* LBA 23:16 */
1241     ide_state->select = cmd_fis[7];      /* LBA 27:24 (LBA28) */
1242     ide_state->hob_sector = cmd_fis[8];  /* LBA 31:24 */
1243     ide_state->hob_lcyl = cmd_fis[9];    /* LBA 39:32 */
1244     ide_state->hob_hcyl = cmd_fis[10];   /* LBA 47:40 */
1245     ide_state->hob_feature = cmd_fis[11];
1246     ide_state->nsector = (int64_t)((cmd_fis[13] << 8) | cmd_fis[12]);
1247     /* 14, 16, 17, 18, 19: Reserved (SATA 1.0) */
1248     /* 15: Only valid when UPDATE_COMMAND not set. */
1249 
1250     /* Copy the ACMD field (ATAPI packet, if any) from the AHCI command
1251      * table to ide_state->io_buffer */
1252     if (opts & AHCI_CMD_ATAPI) {
1253         memcpy(ide_state->io_buffer, &cmd_fis[AHCI_COMMAND_TABLE_ACMD], 0x10);
1254         if (trace_event_get_state_backends(TRACE_HANDLE_REG_H2D_FIS_DUMP)) {
1255             char *pretty_fis = ahci_pretty_buffer_fis(ide_state->io_buffer, 0x10);
1256             trace_handle_reg_h2d_fis_dump(s, port, pretty_fis);
1257             g_free(pretty_fis);
1258         }
1259     }
1260 
1261     ide_state->error = 0;
1262     s->dev[port].done_first_drq = false;
1263     /* Reset transferred byte counter */
1264     cmd->status = 0;
1265 
1266     /* We're ready to process the command in FIS byte 2. */
1267     ide_exec_cmd(&s->dev[port].port, cmd_fis[2]);
1268 }
1269 
1270 static int handle_cmd(AHCIState *s, int port, uint8_t slot)
1271 {
1272     IDEState *ide_state;
1273     uint64_t tbl_addr;
1274     AHCICmdHdr *cmd;
1275     uint8_t *cmd_fis;
1276     dma_addr_t cmd_len;
1277 
1278     if (s->dev[port].port.ifs[0].status & (BUSY_STAT|DRQ_STAT)) {
1279         /* Engine currently busy, try again later */
1280         trace_handle_cmd_busy(s, port);
1281         return -1;
1282     }
1283 
1284     if (!s->dev[port].lst) {
1285         trace_handle_cmd_nolist(s, port);
1286         return -1;
1287     }
1288     cmd = get_cmd_header(s, port, slot);
1289     /* remember current slot handle for later */
1290     s->dev[port].cur_cmd = cmd;
1291 
1292     /* The device we are working for */
1293     ide_state = &s->dev[port].port.ifs[0];
1294     if (!ide_state->blk) {
1295         trace_handle_cmd_badport(s, port);
1296         return -1;
1297     }
1298 
1299     tbl_addr = le64_to_cpu(cmd->tbl_addr);
1300     cmd_len = 0x80;
1301     cmd_fis = dma_memory_map(s->as, tbl_addr, &cmd_len,
1302                              DMA_DIRECTION_FROM_DEVICE);
1303     if (!cmd_fis) {
1304         trace_handle_cmd_badfis(s, port);
1305         return -1;
1306     } else if (cmd_len != 0x80) {
1307         ahci_trigger_irq(s, &s->dev[port], AHCI_PORT_IRQ_BIT_HBFS);
1308         trace_handle_cmd_badmap(s, port, cmd_len);
1309         goto out;
1310     }
1311     if (trace_event_get_state_backends(TRACE_HANDLE_CMD_FIS_DUMP)) {
1312         char *pretty_fis = ahci_pretty_buffer_fis(cmd_fis, 0x80);
1313         trace_handle_cmd_fis_dump(s, port, pretty_fis);
1314         g_free(pretty_fis);
1315     }
1316     switch (cmd_fis[0]) {
1317         case SATA_FIS_TYPE_REGISTER_H2D:
1318             handle_reg_h2d_fis(s, port, slot, cmd_fis);
1319             break;
1320         default:
1321             trace_handle_cmd_unhandled_fis(s, port,
1322                                            cmd_fis[0], cmd_fis[1], cmd_fis[2]);
1323             break;
1324     }
1325 
1326 out:
1327     dma_memory_unmap(s->as, cmd_fis, cmd_len, DMA_DIRECTION_FROM_DEVICE,
1328                      cmd_len);
1329 
1330     if (s->dev[port].port.ifs[0].status & (BUSY_STAT|DRQ_STAT)) {
1331         /* async command, complete later */
1332         s->dev[port].busy_slot = slot;
1333         return -1;
1334     }
1335 
1336     /* done handling the command */
1337     return 0;
1338 }
1339 
1340 /* Transfer PIO data between RAM and device */
1341 static void ahci_pio_transfer(IDEDMA *dma)
1342 {
1343     AHCIDevice *ad = DO_UPCAST(AHCIDevice, dma, dma);
1344     IDEState *s = &ad->port.ifs[0];
1345     uint32_t size = (uint32_t)(s->data_end - s->data_ptr);
1346     /* write == ram -> device */
1347     uint16_t opts = le16_to_cpu(ad->cur_cmd->opts);
1348     int is_write = opts & AHCI_CMD_WRITE;
1349     int is_atapi = opts & AHCI_CMD_ATAPI;
1350     int has_sglist = 0;
1351     bool pio_fis_i;
1352 
1353     /* The PIO Setup FIS is received prior to transfer, but the interrupt
1354      * is only triggered after data is received.
1355      *
1356      * The device only sets the 'I' bit in the PIO Setup FIS for device->host
1357      * requests (see "DPIOI1" in the SATA spec), or for host->device DRQs after
1358      * the first (see "DPIOO1").  The latter is consistent with the spec's
1359      * description of the PACKET protocol, where the command part of ATAPI requests
1360      * ("DPKT0") has the 'I' bit clear, while the data part of PIO ATAPI requests
1361      * ("DPKT4a" and "DPKT7") has the 'I' bit set for both directions for all DRQs.
1362      */
1363     pio_fis_i = ad->done_first_drq || (!is_atapi && !is_write);
1364     ahci_write_fis_pio(ad, size, pio_fis_i);
1365 
1366     if (is_atapi && !ad->done_first_drq) {
1367         /* already prepopulated iobuffer */
1368         goto out;
1369     }
1370 
1371     if (ahci_dma_prepare_buf(dma, size)) {
1372         has_sglist = 1;
1373     }
1374 
1375     trace_ahci_pio_transfer(ad->hba, ad->port_no, is_write ? "writ" : "read",
1376                             size, is_atapi ? "atapi" : "ata",
1377                             has_sglist ? "" : "o");
1378 
1379     if (has_sglist && size) {
1380         if (is_write) {
1381             dma_buf_write(s->data_ptr, size, &s->sg);
1382         } else {
1383             dma_buf_read(s->data_ptr, size, &s->sg);
1384         }
1385     }
1386 
1387     /* Update number of transferred bytes, destroy sglist */
1388     dma_buf_commit(s, size);
1389 
1390 out:
1391     /* declare that we processed everything */
1392     s->data_ptr = s->data_end;
1393 
1394     ad->done_first_drq = true;
1395     if (pio_fis_i) {
1396         ahci_trigger_irq(ad->hba, ad, AHCI_PORT_IRQ_BIT_PSS);
1397     }
1398 }
1399 
1400 static void ahci_start_dma(IDEDMA *dma, IDEState *s,
1401                            BlockCompletionFunc *dma_cb)
1402 {
1403     AHCIDevice *ad = DO_UPCAST(AHCIDevice, dma, dma);
1404     trace_ahci_start_dma(ad->hba, ad->port_no);
1405     s->io_buffer_offset = 0;
1406     dma_cb(s, 0);
1407 }
1408 
1409 static void ahci_restart_dma(IDEDMA *dma)
1410 {
1411     /* Nothing to do, ahci_start_dma already resets s->io_buffer_offset.  */
1412 }
1413 
1414 /**
1415  * IDE/PIO restarts are handled by the core layer, but NCQ commands
1416  * need an extra kick from the AHCI HBA.
1417  */
1418 static void ahci_restart(IDEDMA *dma)
1419 {
1420     AHCIDevice *ad = DO_UPCAST(AHCIDevice, dma, dma);
1421     int i;
1422 
1423     for (i = 0; i < AHCI_MAX_CMDS; i++) {
1424         NCQTransferState *ncq_tfs = &ad->ncq_tfs[i];
1425         if (ncq_tfs->halt) {
1426             execute_ncq_command(ncq_tfs);
1427         }
1428     }
1429 }
1430 
1431 /**
1432  * Called in DMA and PIO R/W chains to read the PRDT.
1433  * Not shared with NCQ pathways.
1434  */
1435 static int32_t ahci_dma_prepare_buf(IDEDMA *dma, int32_t limit)
1436 {
1437     AHCIDevice *ad = DO_UPCAST(AHCIDevice, dma, dma);
1438     IDEState *s = &ad->port.ifs[0];
1439 
1440     if (ahci_populate_sglist(ad, &s->sg, ad->cur_cmd,
1441                              limit, s->io_buffer_offset) == -1) {
1442         trace_ahci_dma_prepare_buf_fail(ad->hba, ad->port_no);
1443         return -1;
1444     }
1445     s->io_buffer_size = s->sg.size;
1446 
1447     trace_ahci_dma_prepare_buf(ad->hba, ad->port_no, limit, s->io_buffer_size);
1448     return s->io_buffer_size;
1449 }
1450 
1451 /**
1452  * Updates the command header with a bytes-read value.
1453  * Called via dma_buf_commit, for both DMA and PIO paths.
1454  * sglist destruction is handled within dma_buf_commit.
1455  */
1456 static void ahci_commit_buf(IDEDMA *dma, uint32_t tx_bytes)
1457 {
1458     AHCIDevice *ad = DO_UPCAST(AHCIDevice, dma, dma);
1459 
1460     tx_bytes += le32_to_cpu(ad->cur_cmd->status);
1461     ad->cur_cmd->status = cpu_to_le32(tx_bytes);
1462 }
1463 
1464 static int ahci_dma_rw_buf(IDEDMA *dma, int is_write)
1465 {
1466     AHCIDevice *ad = DO_UPCAST(AHCIDevice, dma, dma);
1467     IDEState *s = &ad->port.ifs[0];
1468     uint8_t *p = s->io_buffer + s->io_buffer_index;
1469     int l = s->io_buffer_size - s->io_buffer_index;
1470 
1471     if (ahci_populate_sglist(ad, &s->sg, ad->cur_cmd, l, s->io_buffer_offset)) {
1472         return 0;
1473     }
1474 
1475     if (is_write) {
1476         dma_buf_read(p, l, &s->sg);
1477     } else {
1478         dma_buf_write(p, l, &s->sg);
1479     }
1480 
1481     /* free sglist, update byte count */
1482     dma_buf_commit(s, l);
1483     s->io_buffer_index += l;
1484 
1485     trace_ahci_dma_rw_buf(ad->hba, ad->port_no, l);
1486     return 1;
1487 }
1488 
1489 static void ahci_cmd_done(IDEDMA *dma)
1490 {
1491     AHCIDevice *ad = DO_UPCAST(AHCIDevice, dma, dma);
1492 
1493     trace_ahci_cmd_done(ad->hba, ad->port_no);
1494 
1495     /* no longer busy */
1496     if (ad->busy_slot != -1) {
1497         ad->port_regs.cmd_issue &= ~(1 << ad->busy_slot);
1498         ad->busy_slot = -1;
1499     }
1500 
1501     /* update d2h status */
1502     ahci_write_fis_d2h(ad);
1503 
1504     if (ad->port_regs.cmd_issue && !ad->check_bh) {
1505         ad->check_bh = qemu_bh_new(ahci_check_cmd_bh, ad);
1506         qemu_bh_schedule(ad->check_bh);
1507     }
1508 }
1509 
1510 static void ahci_irq_set(void *opaque, int n, int level)
1511 {
1512 }
1513 
1514 static const IDEDMAOps ahci_dma_ops = {
1515     .start_dma = ahci_start_dma,
1516     .restart = ahci_restart,
1517     .restart_dma = ahci_restart_dma,
1518     .pio_transfer = ahci_pio_transfer,
1519     .prepare_buf = ahci_dma_prepare_buf,
1520     .commit_buf = ahci_commit_buf,
1521     .rw_buf = ahci_dma_rw_buf,
1522     .cmd_done = ahci_cmd_done,
1523 };
1524 
1525 void ahci_init(AHCIState *s, DeviceState *qdev)
1526 {
1527     s->container = qdev;
1528     /* XXX BAR size should be 1k, but that breaks, so bump it to 4k for now */
1529     memory_region_init_io(&s->mem, OBJECT(qdev), &ahci_mem_ops, s,
1530                           "ahci", AHCI_MEM_BAR_SIZE);
1531     memory_region_init_io(&s->idp, OBJECT(qdev), &ahci_idp_ops, s,
1532                           "ahci-idp", 32);
1533 }
1534 
1535 void ahci_realize(AHCIState *s, DeviceState *qdev, AddressSpace *as, int ports)
1536 {
1537     qemu_irq *irqs;
1538     int i;
1539 
1540     s->as = as;
1541     s->ports = ports;
1542     s->dev = g_new0(AHCIDevice, ports);
1543     ahci_reg_init(s);
1544     irqs = qemu_allocate_irqs(ahci_irq_set, s, s->ports);
1545     for (i = 0; i < s->ports; i++) {
1546         AHCIDevice *ad = &s->dev[i];
1547 
1548         ide_bus_new(&ad->port, sizeof(ad->port), qdev, i, 1);
1549         ide_init2(&ad->port, irqs[i]);
1550 
1551         ad->hba = s;
1552         ad->port_no = i;
1553         ad->port.dma = &ad->dma;
1554         ad->port.dma->ops = &ahci_dma_ops;
1555         ide_register_restart_cb(&ad->port);
1556     }
1557     g_free(irqs);
1558 }
1559 
1560 void ahci_uninit(AHCIState *s)
1561 {
1562     int i, j;
1563 
1564     for (i = 0; i < s->ports; i++) {
1565         AHCIDevice *ad = &s->dev[i];
1566 
1567         for (j = 0; j < 2; j++) {
1568             IDEState *s = &ad->port.ifs[j];
1569 
1570             ide_exit(s);
1571         }
1572         object_unparent(OBJECT(&ad->port));
1573     }
1574 
1575     g_free(s->dev);
1576 }
1577 
1578 void ahci_reset(AHCIState *s)
1579 {
1580     AHCIPortRegs *pr;
1581     int i;
1582 
1583     trace_ahci_reset(s);
1584 
1585     s->control_regs.irqstatus = 0;
1586     /* AHCI Enable (AE)
1587      * The implementation of this bit is dependent upon the value of the
1588      * CAP.SAM bit. If CAP.SAM is '0', then GHC.AE shall be read-write and
1589      * shall have a reset value of '0'. If CAP.SAM is '1', then AE shall be
1590      * read-only and shall have a reset value of '1'.
1591      *
1592      * We set HOST_CAP_AHCI so we must enable AHCI at reset.
1593      */
1594     s->control_regs.ghc = HOST_CTL_AHCI_EN;
1595 
1596     for (i = 0; i < s->ports; i++) {
1597         pr = &s->dev[i].port_regs;
1598         pr->irq_stat = 0;
1599         pr->irq_mask = 0;
1600         pr->scr_ctl = 0;
1601         pr->cmd = PORT_CMD_SPIN_UP | PORT_CMD_POWER_ON;
1602         ahci_reset_port(s, i);
1603     }
1604 }
1605 
1606 static const VMStateDescription vmstate_ncq_tfs = {
1607     .name = "ncq state",
1608     .version_id = 1,
1609     .fields = (VMStateField[]) {
1610         VMSTATE_UINT32(sector_count, NCQTransferState),
1611         VMSTATE_UINT64(lba, NCQTransferState),
1612         VMSTATE_UINT8(tag, NCQTransferState),
1613         VMSTATE_UINT8(cmd, NCQTransferState),
1614         VMSTATE_UINT8(slot, NCQTransferState),
1615         VMSTATE_BOOL(used, NCQTransferState),
1616         VMSTATE_BOOL(halt, NCQTransferState),
1617         VMSTATE_END_OF_LIST()
1618     },
1619 };
1620 
1621 static const VMStateDescription vmstate_ahci_device = {
1622     .name = "ahci port",
1623     .version_id = 1,
1624     .fields = (VMStateField[]) {
1625         VMSTATE_IDE_BUS(port, AHCIDevice),
1626         VMSTATE_IDE_DRIVE(port.ifs[0], AHCIDevice),
1627         VMSTATE_UINT32(port_state, AHCIDevice),
1628         VMSTATE_UINT32(finished, AHCIDevice),
1629         VMSTATE_UINT32(port_regs.lst_addr, AHCIDevice),
1630         VMSTATE_UINT32(port_regs.lst_addr_hi, AHCIDevice),
1631         VMSTATE_UINT32(port_regs.fis_addr, AHCIDevice),
1632         VMSTATE_UINT32(port_regs.fis_addr_hi, AHCIDevice),
1633         VMSTATE_UINT32(port_regs.irq_stat, AHCIDevice),
1634         VMSTATE_UINT32(port_regs.irq_mask, AHCIDevice),
1635         VMSTATE_UINT32(port_regs.cmd, AHCIDevice),
1636         VMSTATE_UINT32(port_regs.tfdata, AHCIDevice),
1637         VMSTATE_UINT32(port_regs.sig, AHCIDevice),
1638         VMSTATE_UINT32(port_regs.scr_stat, AHCIDevice),
1639         VMSTATE_UINT32(port_regs.scr_ctl, AHCIDevice),
1640         VMSTATE_UINT32(port_regs.scr_err, AHCIDevice),
1641         VMSTATE_UINT32(port_regs.scr_act, AHCIDevice),
1642         VMSTATE_UINT32(port_regs.cmd_issue, AHCIDevice),
1643         VMSTATE_BOOL(done_first_drq, AHCIDevice),
1644         VMSTATE_INT32(busy_slot, AHCIDevice),
1645         VMSTATE_BOOL(init_d2h_sent, AHCIDevice),
1646         VMSTATE_STRUCT_ARRAY(ncq_tfs, AHCIDevice, AHCI_MAX_CMDS,
1647                              1, vmstate_ncq_tfs, NCQTransferState),
1648         VMSTATE_END_OF_LIST()
1649     },
1650 };
1651 
1652 static int ahci_state_post_load(void *opaque, int version_id)
1653 {
1654     int i, j;
1655     struct AHCIDevice *ad;
1656     NCQTransferState *ncq_tfs;
1657     AHCIPortRegs *pr;
1658     AHCIState *s = opaque;
1659 
1660     for (i = 0; i < s->ports; i++) {
1661         ad = &s->dev[i];
1662         pr = &ad->port_regs;
1663 
1664         if (!(pr->cmd & PORT_CMD_START) && (pr->cmd & PORT_CMD_LIST_ON)) {
1665             error_report("AHCI: DMA engine should be off, but status bit "
1666                          "indicates it is still running.");
1667             return -1;
1668         }
1669         if (!(pr->cmd & PORT_CMD_FIS_RX) && (pr->cmd & PORT_CMD_FIS_ON)) {
1670             error_report("AHCI: FIS RX engine should be off, but status bit "
1671                          "indicates it is still running.");
1672             return -1;
1673         }
1674 
1675         /* After a migrate, the DMA/FIS engines are "off" and
1676          * need to be conditionally restarted */
1677         pr->cmd &= ~(PORT_CMD_LIST_ON | PORT_CMD_FIS_ON);
1678         if (ahci_cond_start_engines(ad) != 0) {
1679             return -1;
1680         }
1681 
1682         for (j = 0; j < AHCI_MAX_CMDS; j++) {
1683             ncq_tfs = &ad->ncq_tfs[j];
1684             ncq_tfs->drive = ad;
1685 
1686             if (ncq_tfs->used != ncq_tfs->halt) {
1687                 return -1;
1688             }
1689             if (!ncq_tfs->halt) {
1690                 continue;
1691             }
1692             if (!is_ncq(ncq_tfs->cmd)) {
1693                 return -1;
1694             }
1695             if (ncq_tfs->slot != ncq_tfs->tag) {
1696                 return -1;
1697             }
1698             /* If ncq_tfs->halt is justly set, the engine should be engaged,
1699              * and the command list buffer should be mapped. */
1700             ncq_tfs->cmdh = get_cmd_header(s, i, ncq_tfs->slot);
1701             if (!ncq_tfs->cmdh) {
1702                 return -1;
1703             }
1704             ahci_populate_sglist(ncq_tfs->drive, &ncq_tfs->sglist,
1705                                  ncq_tfs->cmdh, ncq_tfs->sector_count * 512,
1706                                  0);
1707             if (ncq_tfs->sector_count != ncq_tfs->sglist.size >> 9) {
1708                 return -1;
1709             }
1710         }
1711 
1712 
1713         /*
1714          * If an error is present, ad->busy_slot will be valid and not -1.
1715          * In this case, an operation is waiting to resume and will re-check
1716          * for additional AHCI commands to execute upon completion.
1717          *
1718          * In the case where no error was present, busy_slot will be -1,
1719          * and we should check to see if there are additional commands waiting.
1720          */
1721         if (ad->busy_slot == -1) {
1722             check_cmd(s, i);
1723         } else {
1724             /* We are in the middle of a command, and may need to access
1725              * the command header in guest memory again. */
1726             if (ad->busy_slot < 0 || ad->busy_slot >= AHCI_MAX_CMDS) {
1727                 return -1;
1728             }
1729             ad->cur_cmd = get_cmd_header(s, i, ad->busy_slot);
1730         }
1731     }
1732 
1733     return 0;
1734 }
1735 
1736 const VMStateDescription vmstate_ahci = {
1737     .name = "ahci",
1738     .version_id = 1,
1739     .post_load = ahci_state_post_load,
1740     .fields = (VMStateField[]) {
1741         VMSTATE_STRUCT_VARRAY_POINTER_INT32(dev, AHCIState, ports,
1742                                      vmstate_ahci_device, AHCIDevice),
1743         VMSTATE_UINT32(control_regs.cap, AHCIState),
1744         VMSTATE_UINT32(control_regs.ghc, AHCIState),
1745         VMSTATE_UINT32(control_regs.irqstatus, AHCIState),
1746         VMSTATE_UINT32(control_regs.impl, AHCIState),
1747         VMSTATE_UINT32(control_regs.version, AHCIState),
1748         VMSTATE_UINT32(idp_index, AHCIState),
1749         VMSTATE_INT32_EQUAL(ports, AHCIState, NULL),
1750         VMSTATE_END_OF_LIST()
1751     },
1752 };
1753 
1754 static const VMStateDescription vmstate_sysbus_ahci = {
1755     .name = "sysbus-ahci",
1756     .fields = (VMStateField[]) {
1757         VMSTATE_AHCI(ahci, SysbusAHCIState),
1758         VMSTATE_END_OF_LIST()
1759     },
1760 };
1761 
1762 static void sysbus_ahci_reset(DeviceState *dev)
1763 {
1764     SysbusAHCIState *s = SYSBUS_AHCI(dev);
1765 
1766     ahci_reset(&s->ahci);
1767 }
1768 
1769 static void sysbus_ahci_init(Object *obj)
1770 {
1771     SysbusAHCIState *s = SYSBUS_AHCI(obj);
1772     SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
1773 
1774     ahci_init(&s->ahci, DEVICE(obj));
1775 
1776     sysbus_init_mmio(sbd, &s->ahci.mem);
1777     sysbus_init_irq(sbd, &s->ahci.irq);
1778 }
1779 
1780 static void sysbus_ahci_realize(DeviceState *dev, Error **errp)
1781 {
1782     SysbusAHCIState *s = SYSBUS_AHCI(dev);
1783 
1784     ahci_realize(&s->ahci, dev, &address_space_memory, s->num_ports);
1785 }
1786 
1787 static Property sysbus_ahci_properties[] = {
1788     DEFINE_PROP_UINT32("num-ports", SysbusAHCIState, num_ports, 1),
1789     DEFINE_PROP_END_OF_LIST(),
1790 };
1791 
1792 static void sysbus_ahci_class_init(ObjectClass *klass, void *data)
1793 {
1794     DeviceClass *dc = DEVICE_CLASS(klass);
1795 
1796     dc->realize = sysbus_ahci_realize;
1797     dc->vmsd = &vmstate_sysbus_ahci;
1798     dc->props = sysbus_ahci_properties;
1799     dc->reset = sysbus_ahci_reset;
1800     set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
1801 }
1802 
1803 static const TypeInfo sysbus_ahci_info = {
1804     .name          = TYPE_SYSBUS_AHCI,
1805     .parent        = TYPE_SYS_BUS_DEVICE,
1806     .instance_size = sizeof(SysbusAHCIState),
1807     .instance_init = sysbus_ahci_init,
1808     .class_init    = sysbus_ahci_class_init,
1809 };
1810 
1811 static void sysbus_ahci_register_types(void)
1812 {
1813     type_register_static(&sysbus_ahci_info);
1814 }
1815 
1816 type_init(sysbus_ahci_register_types)
1817 
1818 int32_t ahci_get_num_ports(PCIDevice *dev)
1819 {
1820     AHCIPCIState *d = ICH_AHCI(dev);
1821     AHCIState *ahci = &d->ahci;
1822 
1823     return ahci->ports;
1824 }
1825 
1826 void ahci_ide_create_devs(PCIDevice *dev, DriveInfo **hd)
1827 {
1828     AHCIPCIState *d = ICH_AHCI(dev);
1829     AHCIState *ahci = &d->ahci;
1830     int i;
1831 
1832     for (i = 0; i < ahci->ports; i++) {
1833         if (hd[i] == NULL) {
1834             continue;
1835         }
1836         ide_create_drive(&ahci->dev[i].port, 0, hd[i]);
1837     }
1838 
1839 }
1840