3 * Copyright (C) 1998-2003 Brian Palmer <brianp@sginet.com>
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
27 UCHAR PacketSize
; // 00h - Size of packet (10h or 18h)
28 UCHAR Reserved
; // 01h - Reserved (0)
29 USHORT LBABlockCount
; // 02h - Number of blocks to transfer (max 007Fh for Phoenix EDD)
30 USHORT TransferBufferOffset
; // 04h - Transfer buffer offset (seg:off)
31 USHORT TransferBufferSegment
; // Transfer buffer segment (seg:off)
32 ULONGLONG LBAStartBlock
; // 08h - Starting absolute block number
33 //ULONGLONG TransferBuffer64; // 10h - (EDD-3.0, optional) 64-bit flat address of transfer buffer
34 // used if DWORD at 04h is FFFFh:FFFFh
35 // Commented since some earlier BIOSes refuse to work with
36 // such extended structure
37 } PACKED I386_DISK_ADDRESS_PACKET
, *PI386_DISK_ADDRESS_PACKET
;
39 /////////////////////////////////////////////////////////////////////////////////////////////
41 /////////////////////////////////////////////////////////////////////////////////////////////
43 static BOOLEAN
PcDiskResetController(ULONG DriveNumber
)
48 DbgPrint((DPRINT_DISK
, "PcDiskResetController(0x%x) DISK OPERATION FAILED -- RESETTING CONTROLLER\n", DriveNumber
));
50 // BIOS Int 13h, function 0 - Reset disk system
52 // DL = drive (if bit 7 is set both hard disks and floppy disks reset)
55 // CF clear if successful
58 RegsIn
.b
.dl
= DriveNumber
;
60 // Reset the disk controller
61 Int386(0x13, &RegsIn
, &RegsOut
);
63 return INT386_SUCCESS(RegsOut
);
66 static BOOLEAN
PcDiskReadLogicalSectorsLBA(ULONG DriveNumber
, ULONGLONG SectorNumber
, ULONG SectorCount
, PVOID Buffer
)
71 PI386_DISK_ADDRESS_PACKET Packet
= (PI386_DISK_ADDRESS_PACKET
)(BIOSCALLBUFFER
);
73 DbgPrint((DPRINT_DISK
, "PcDiskReadLogicalSectorsLBA() DriveNumber: 0x%x SectorNumber: %I64d SectorCount: %d Buffer: 0x%x\n", DriveNumber
, SectorNumber
, SectorCount
, Buffer
));
75 // BIOS int 0x13, function 42h - IBM/MS INT 13 Extensions - EXTENDED READ
76 RegsIn
.b
.ah
= 0x42; // Subfunction 42h
77 RegsIn
.b
.dl
= DriveNumber
; // Drive number in DL (0 - floppy, 0x80 - harddisk)
78 RegsIn
.x
.ds
= BIOSCALLBUFSEGMENT
; // DS:SI -> disk address packet
79 RegsIn
.w
.si
= BIOSCALLBUFOFFSET
;
81 // Setup disk address packet
82 RtlZeroMemory(Packet
, sizeof(I386_DISK_ADDRESS_PACKET
));
83 Packet
->PacketSize
= sizeof(I386_DISK_ADDRESS_PACKET
);
85 Packet
->LBABlockCount
= SectorCount
;
86 Packet
->TransferBufferOffset
= ((ULONG
)Buffer
) & 0x0F;
87 Packet
->TransferBufferSegment
= ((ULONG
)Buffer
) >> 4;
88 Packet
->LBAStartBlock
= SectorNumber
;
90 // BIOS int 0x13, function 42h - IBM/MS INT 13 Extensions - EXTENDED READ
92 // CF clear if successful
96 // disk address packet's block count field set to the
97 // number of blocks successfully transferred
100 for (RetryCount
=0; RetryCount
<3; RetryCount
++)
102 Int386(0x13, &RegsIn
, &RegsOut
);
104 // If it worked return TRUE
105 if (INT386_SUCCESS(RegsOut
))
109 // If it was a corrected ECC error then the data is still good
110 else if (RegsOut
.b
.ah
== 0x11)
114 // If it failed the do the next retry
117 PcDiskResetController(DriveNumber
);
123 // If we get here then the read failed
124 DiskError("Disk Read Failed in LBA mode", RegsOut
.b
.ah
);
129 static BOOLEAN
PcDiskReadLogicalSectorsCHS(ULONG DriveNumber
, ULONGLONG SectorNumber
, ULONG SectorCount
, PVOID Buffer
)
131 ULONG PhysicalSector
;
134 GEOMETRY DriveGeometry
;
135 ULONG NumberOfSectorsToRead
;
140 DbgPrint((DPRINT_DISK
, "PcDiskReadLogicalSectorsCHS()\n"));
143 // Get the drive geometry
145 if (!MachDiskGetDriveGeometry(DriveNumber
, &DriveGeometry
) ||
146 DriveGeometry
.Sectors
== 0 ||
147 DriveGeometry
.Heads
== 0)
156 // Calculate the physical disk offsets
158 PhysicalSector
= 1 + (SectorNumber
% DriveGeometry
.Sectors
);
159 PhysicalHead
= (SectorNumber
/ DriveGeometry
.Sectors
) % DriveGeometry
.Heads
;
160 PhysicalTrack
= (SectorNumber
/ DriveGeometry
.Sectors
) / DriveGeometry
.Heads
;
163 // Calculate how many sectors we need to read this round
165 if (PhysicalSector
> 1)
167 if (SectorCount
>= (DriveGeometry
.Sectors
- (PhysicalSector
- 1)))
168 NumberOfSectorsToRead
= (DriveGeometry
.Sectors
- (PhysicalSector
- 1));
170 NumberOfSectorsToRead
= SectorCount
;
174 if (SectorCount
>= DriveGeometry
.Sectors
)
175 NumberOfSectorsToRead
= DriveGeometry
.Sectors
;
177 NumberOfSectorsToRead
= SectorCount
;
181 // Make sure the read is within the geometry boundaries
183 if ((PhysicalHead
>= DriveGeometry
.Heads
) ||
184 (PhysicalTrack
>= DriveGeometry
.Cylinders
) ||
185 ((NumberOfSectorsToRead
+ PhysicalSector
) > (DriveGeometry
.Sectors
+ 1)) ||
186 (PhysicalSector
> DriveGeometry
.Sectors
))
188 DiskError("Disk read exceeds drive geometry limits.", 0);
192 // BIOS Int 13h, function 2 - Read Disk Sectors
194 // AL = number of sectors to read (must be nonzero)
195 // CH = low eight bits of cylinder number
196 // CL = sector number 1-63 (bits 0-5)
197 // high two bits of cylinder (bits 6-7, hard disk only)
199 // DL = drive number (bit 7 set for hard disk)
200 // ES:BX -> data buffer
203 // if AH = 11h (corrected ECC error), AL = burst length
204 // CF clear if successful
206 // AL = number of sectors transferred
207 // (only valid if CF set for some BIOSes)
209 RegsIn
.b
.al
= NumberOfSectorsToRead
;
210 RegsIn
.b
.ch
= (PhysicalTrack
& 0xFF);
211 RegsIn
.b
.cl
= (PhysicalSector
+ ((PhysicalTrack
& 0x300) >> 2));
212 RegsIn
.b
.dh
= PhysicalHead
;
213 RegsIn
.b
.dl
= DriveNumber
;
214 RegsIn
.w
.es
= ((ULONG
)Buffer
) >> 4;
215 RegsIn
.w
.bx
= ((ULONG
)Buffer
) & 0x0F;
221 for (RetryCount
=0; RetryCount
<3; RetryCount
++)
223 Int386(0x13, &RegsIn
, &RegsOut
);
225 // If it worked break out
226 if (INT386_SUCCESS(RegsOut
))
230 // If it was a corrected ECC error then the data is still good
231 else if (RegsOut
.b
.ah
== 0x11)
235 // If it failed the do the next retry
238 PcDiskResetController(DriveNumber
);
244 // If we retried 3 times then fail
247 DiskError("Disk Read Failed in CHS mode, after retrying 3 times", RegsOut
.b
.ah
);
251 // I have learned that not all bioses return
252 // the sector read count in the AL register (at least mine doesn't)
253 // even if the sectors were read correctly. So instead
254 // of checking the sector read count we will rely solely
255 // on the carry flag being set on error
257 Buffer
= (PVOID
)((ULONG_PTR
)Buffer
+ (NumberOfSectorsToRead
* DriveGeometry
.BytesPerSector
));
258 SectorCount
-= NumberOfSectorsToRead
;
259 SectorNumber
+= NumberOfSectorsToRead
;
265 static BOOLEAN
PcDiskInt13ExtensionsSupported(ULONG DriveNumber
)
267 static ULONG LastDriveNumber
= 0xffffffff;
268 static BOOLEAN LastSupported
;
272 DbgPrint((DPRINT_DISK
, "PcDiskInt13ExtensionsSupported()\n"));
274 if (DriveNumber
== LastDriveNumber
)
276 DbgPrint((DPRINT_DISK
, "Using cached value %s for drive 0x%x\n", LastSupported
? "TRUE" : "FALSE", DriveNumber
));
277 return LastSupported
;
280 // Some BIOSes report that extended disk access functions are not supported
281 // when booting from a CD (e.g. Phoenix BIOS v6.00PG and Insyde BIOS shipping
282 // with Intel Macs). Therefore we just return TRUE if we're booting from a CD -
283 // we can assume that all El Torito capable BIOSes support INT 13 extensions.
284 // We simply detect whether we're booting from CD by checking whether the drive
285 // number is >= 0x90. It's 0x90 on the Insyde BIOS, and 0x9F on most other BIOSes.
286 if (DriveNumber
>= 0x90)
288 LastSupported
= TRUE
;
292 LastDriveNumber
= DriveNumber
;
294 // IBM/MS INT 13 Extensions - INSTALLATION CHECK
297 // DL = drive (80h-FFh)
299 // CF set on error (extensions not supported)
300 // AH = 01h (invalid function)
301 // CF clear if successful
302 // BX = AA55h if installed
303 // AH = major version of extensions
305 // 20h = 2.0 / EDD-1.0
306 // 21h = 2.1 / EDD-1.1
309 // CX = API subset support bitmap
310 // DH = extension version (v2.0+ ??? -- not present in 1.x)
312 // Bitfields for IBM/MS INT 13 Extensions API support bitmap
313 // Bit 0, extended disk access functions (AH=42h-44h,47h,48h) supported
314 // Bit 1, removable drive controller functions (AH=45h,46h,48h,49h,INT 15/AH=52h) supported
315 // Bit 2, enhanced disk drive (EDD) functions (AH=48h,AH=4Eh) supported
316 // extended drive parameter table is valid
317 // Bits 3-15 reserved
319 RegsIn
.w
.bx
= 0x55AA;
320 RegsIn
.b
.dl
= DriveNumber
;
322 // Reset the disk controller
323 Int386(0x13, &RegsIn
, &RegsOut
);
325 if (!INT386_SUCCESS(RegsOut
))
327 // CF set on error (extensions not supported)
328 LastSupported
= FALSE
;
332 if (RegsOut
.w
.bx
!= 0xAA55)
334 // BX = AA55h if installed
335 LastSupported
= FALSE
;
339 if (!(RegsOut
.w
.cx
& 0x0001))
341 // CX = API subset support bitmap
342 // Bit 0, extended disk access functions (AH=42h-44h,47h,48h) supported
343 printf("Suspicious API subset support bitmap 0x%x on device 0x%lx\n", RegsOut
.w
.cx
, DriveNumber
);
344 LastSupported
= FALSE
;
348 LastSupported
= TRUE
;
352 BOOLEAN
PcDiskReadLogicalSectors(ULONG DriveNumber
, ULONGLONG SectorNumber
, ULONG SectorCount
, PVOID Buffer
)
355 DbgPrint((DPRINT_DISK
, "PcDiskReadLogicalSectors() DriveNumber: 0x%x SectorNumber: %I64d SectorCount: %d Buffer: 0x%x\n", DriveNumber
, SectorNumber
, SectorCount
, Buffer
));
358 // Check to see if it is a fixed disk drive
359 // If so then check to see if Int13 extensions work
360 // If they do then use them, otherwise default back to BIOS calls
362 if ((DriveNumber
>= 0x80) && PcDiskInt13ExtensionsSupported(DriveNumber
))
364 DbgPrint((DPRINT_DISK
, "Using Int 13 Extensions for read. PcDiskInt13ExtensionsSupported(%d) = %s\n", DriveNumber
, PcDiskInt13ExtensionsSupported(DriveNumber
) ? "TRUE" : "FALSE"));
367 // LBA is easy, nothing to calculate
370 return PcDiskReadLogicalSectorsLBA(DriveNumber
, SectorNumber
, SectorCount
, Buffer
);
374 // LBA is not supported default to the CHS calls
375 return PcDiskReadLogicalSectorsCHS(DriveNumber
, SectorNumber
, SectorCount
, Buffer
);
382 PcDiskGetDriveGeometry(ULONG DriveNumber
, PGEOMETRY Geometry
)
388 DbgPrint((DPRINT_DISK
, "DiskGetDriveGeometry()\n"));
390 /* BIOS Int 13h, function 08h - Get drive parameters
392 * DL = drive (bit 7 set for hard disk)
393 * ES:DI = 0000h:0000h to guard against BIOS bugs
397 * CF clear if successful
399 * AL = 00h on at least some BIOSes
400 * BL = drive type (AT/PS2 floppies only)
401 * CH = low eight bits of maximum cylinder number
402 * CL = maximum sector number (bits 5-0)
403 * high two bits of maximum cylinder number (bits 7-6)
404 * DH = maximum head number
405 * DL = number of drives
406 * ES:DI -> drive parameter table (floppies only)
409 RegsIn
.b
.dl
= DriveNumber
;
410 RegsIn
.w
.es
= 0x0000;
411 RegsIn
.w
.di
= 0x0000;
413 /* Get drive parameters */
414 Int386(0x13, &RegsIn
, &RegsOut
);
416 if (! INT386_SUCCESS(RegsOut
))
421 Cylinders
= (RegsOut
.b
.cl
& 0xC0) << 2;
422 Cylinders
+= RegsOut
.b
.ch
;
424 Geometry
->Cylinders
= Cylinders
;
425 Geometry
->Heads
= RegsOut
.b
.dh
+ 1;
426 Geometry
->Sectors
= RegsOut
.b
.cl
& 0x3F;
427 Geometry
->BytesPerSector
= 512; /* Just assume 512 bytes per sector */
433 PcDiskGetCacheableBlockCount(ULONG DriveNumber
)
437 /* If LBA is supported then the block size will be 64 sectors (32k)
438 * If not then the block size is the size of one track */
439 if (DiskInt13ExtensionsSupported(DriveNumber
))
443 /* Get the disk geometry
444 * If this fails then we will just return 1 sector to be safe */
445 else if (! PcDiskGetDriveGeometry(DriveNumber
, &Geometry
))
451 return Geometry
.Sectors
;