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 along
16 * with this program; if not, write to the Free Software Foundation, Inc.,
17 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
28 UCHAR PacketSize
; // 00h - Size of packet (10h or 18h)
29 UCHAR Reserved
; // 01h - Reserved (0)
30 USHORT LBABlockCount
; // 02h - Number of blocks to transfer (max 007Fh for Phoenix EDD)
31 USHORT TransferBufferOffset
; // 04h - Transfer buffer offset (seg:off)
32 USHORT TransferBufferSegment
; // Transfer buffer segment (seg:off)
33 ULONGLONG LBAStartBlock
; // 08h - Starting absolute block number
34 //ULONGLONG TransferBuffer64; // 10h - (EDD-3.0, optional) 64-bit flat address of transfer buffer
35 // used if DWORD at 04h is FFFFh:FFFFh
36 // Commented since some earlier BIOSes refuse to work with
37 // such extended structure
38 } I386_DISK_ADDRESS_PACKET
, *PI386_DISK_ADDRESS_PACKET
;
41 /////////////////////////////////////////////////////////////////////////////////////////////
43 /////////////////////////////////////////////////////////////////////////////////////////////
45 static BOOLEAN
PcDiskResetController(ULONG DriveNumber
)
50 DPRINTM(DPRINT_DISK
, "PcDiskResetController(0x%x) DISK OPERATION FAILED -- RESETTING CONTROLLER\n", DriveNumber
);
52 // BIOS Int 13h, function 0 - Reset disk system
54 // DL = drive (if bit 7 is set both hard disks and floppy disks reset)
57 // CF clear if successful
60 RegsIn
.b
.dl
= DriveNumber
;
62 // Reset the disk controller
63 Int386(0x13, &RegsIn
, &RegsOut
);
65 return INT386_SUCCESS(RegsOut
);
68 static BOOLEAN
PcDiskReadLogicalSectorsLBA(ULONG DriveNumber
, ULONGLONG SectorNumber
, ULONG SectorCount
, PVOID Buffer
)
73 PI386_DISK_ADDRESS_PACKET Packet
= (PI386_DISK_ADDRESS_PACKET
)(BIOSCALLBUFFER
);
75 DPRINTM(DPRINT_DISK
, "PcDiskReadLogicalSectorsLBA() DriveNumber: 0x%x SectorNumber: %I64d SectorCount: %d Buffer: 0x%x\n", DriveNumber
, SectorNumber
, SectorCount
, Buffer
);
77 // BIOS int 0x13, function 42h - IBM/MS INT 13 Extensions - EXTENDED READ
78 RegsIn
.b
.ah
= 0x42; // Subfunction 42h
79 RegsIn
.b
.dl
= DriveNumber
; // Drive number in DL (0 - floppy, 0x80 - harddisk)
80 RegsIn
.x
.ds
= BIOSCALLBUFSEGMENT
; // DS:SI -> disk address packet
81 RegsIn
.w
.si
= BIOSCALLBUFOFFSET
;
83 // Setup disk address packet
84 RtlZeroMemory(Packet
, sizeof(I386_DISK_ADDRESS_PACKET
));
85 Packet
->PacketSize
= sizeof(I386_DISK_ADDRESS_PACKET
);
87 Packet
->LBABlockCount
= SectorCount
;
88 Packet
->TransferBufferOffset
= ((ULONG_PTR
)Buffer
) & 0x0F;
89 Packet
->TransferBufferSegment
= ((ULONG_PTR
)Buffer
) >> 4;
90 Packet
->LBAStartBlock
= SectorNumber
;
92 // BIOS int 0x13, function 42h - IBM/MS INT 13 Extensions - EXTENDED READ
94 // CF clear if successful
98 // disk address packet's block count field set to the
99 // number of blocks successfully transferred
102 for (RetryCount
=0; RetryCount
<3; RetryCount
++)
104 Int386(0x13, &RegsIn
, &RegsOut
);
106 // If it worked return TRUE
107 if (INT386_SUCCESS(RegsOut
))
111 // If it was a corrected ECC error then the data is still good
112 else if (RegsOut
.b
.ah
== 0x11)
116 // If it failed the do the next retry
119 PcDiskResetController(DriveNumber
);
125 // If we get here then the read failed
126 DiskError("Disk Read Failed in LBA mode", RegsOut
.b
.ah
);
131 static BOOLEAN
PcDiskReadLogicalSectorsCHS(ULONG DriveNumber
, ULONGLONG SectorNumber
, ULONG SectorCount
, PVOID Buffer
)
133 ULONG PhysicalSector
;
136 GEOMETRY DriveGeometry
;
137 ULONG NumberOfSectorsToRead
;
142 DPRINTM(DPRINT_DISK
, "PcDiskReadLogicalSectorsCHS()\n");
145 // Get the drive geometry
147 if (!MachDiskGetDriveGeometry(DriveNumber
, &DriveGeometry
) ||
148 DriveGeometry
.Sectors
== 0 ||
149 DriveGeometry
.Heads
== 0)
158 // Calculate the physical disk offsets
160 PhysicalSector
= 1 + (SectorNumber
% DriveGeometry
.Sectors
);
161 PhysicalHead
= (SectorNumber
/ DriveGeometry
.Sectors
) % DriveGeometry
.Heads
;
162 PhysicalTrack
= (SectorNumber
/ DriveGeometry
.Sectors
) / DriveGeometry
.Heads
;
165 // Calculate how many sectors we need to read this round
167 if (PhysicalSector
> 1)
169 if (SectorCount
>= (DriveGeometry
.Sectors
- (PhysicalSector
- 1)))
170 NumberOfSectorsToRead
= (DriveGeometry
.Sectors
- (PhysicalSector
- 1));
172 NumberOfSectorsToRead
= SectorCount
;
176 if (SectorCount
>= DriveGeometry
.Sectors
)
177 NumberOfSectorsToRead
= DriveGeometry
.Sectors
;
179 NumberOfSectorsToRead
= SectorCount
;
183 // Make sure the read is within the geometry boundaries
185 if ((PhysicalHead
>= DriveGeometry
.Heads
) ||
186 (PhysicalTrack
>= DriveGeometry
.Cylinders
) ||
187 ((NumberOfSectorsToRead
+ PhysicalSector
) > (DriveGeometry
.Sectors
+ 1)) ||
188 (PhysicalSector
> DriveGeometry
.Sectors
))
190 DiskError("Disk read exceeds drive geometry limits.", 0);
194 // BIOS Int 13h, function 2 - Read Disk Sectors
196 // AL = number of sectors to read (must be nonzero)
197 // CH = low eight bits of cylinder number
198 // CL = sector number 1-63 (bits 0-5)
199 // high two bits of cylinder (bits 6-7, hard disk only)
201 // DL = drive number (bit 7 set for hard disk)
202 // ES:BX -> data buffer
205 // if AH = 11h (corrected ECC error), AL = burst length
206 // CF clear if successful
208 // AL = number of sectors transferred
209 // (only valid if CF set for some BIOSes)
211 RegsIn
.b
.al
= NumberOfSectorsToRead
;
212 RegsIn
.b
.ch
= (PhysicalTrack
& 0xFF);
213 RegsIn
.b
.cl
= (PhysicalSector
+ ((PhysicalTrack
& 0x300) >> 2));
214 RegsIn
.b
.dh
= PhysicalHead
;
215 RegsIn
.b
.dl
= DriveNumber
;
216 RegsIn
.w
.es
= ((ULONG_PTR
)Buffer
) >> 4;
217 RegsIn
.w
.bx
= ((ULONG_PTR
)Buffer
) & 0x0F;
223 for (RetryCount
=0; RetryCount
<3; RetryCount
++)
225 Int386(0x13, &RegsIn
, &RegsOut
);
227 // If it worked break out
228 if (INT386_SUCCESS(RegsOut
))
232 // If it was a corrected ECC error then the data is still good
233 else if (RegsOut
.b
.ah
== 0x11)
237 // If it failed the do the next retry
240 PcDiskResetController(DriveNumber
);
246 // If we retried 3 times then fail
249 DiskError("Disk Read Failed in CHS mode, after retrying 3 times", RegsOut
.b
.ah
);
253 // I have learned that not all bioses return
254 // the sector read count in the AL register (at least mine doesn't)
255 // even if the sectors were read correctly. So instead
256 // of checking the sector read count we will rely solely
257 // on the carry flag being set on error
259 Buffer
= (PVOID
)((ULONG_PTR
)Buffer
+ (NumberOfSectorsToRead
* DriveGeometry
.BytesPerSector
));
260 SectorCount
-= NumberOfSectorsToRead
;
261 SectorNumber
+= NumberOfSectorsToRead
;
267 static BOOLEAN
PcDiskInt13ExtensionsSupported(ULONG DriveNumber
)
269 static ULONG LastDriveNumber
= 0xffffffff;
270 static BOOLEAN LastSupported
;
274 DPRINTM(DPRINT_DISK
, "PcDiskInt13ExtensionsSupported()\n");
276 if (DriveNumber
== LastDriveNumber
)
278 DPRINTM(DPRINT_DISK
, "Using cached value %s for drive 0x%x\n", LastSupported
? "TRUE" : "FALSE", DriveNumber
);
279 return LastSupported
;
282 // Some BIOSes report that extended disk access functions are not supported
283 // when booting from a CD (e.g. Phoenix BIOS v6.00PG and Insyde BIOS shipping
284 // with Intel Macs). Therefore we just return TRUE if we're booting from a CD -
285 // we can assume that all El Torito capable BIOSes support INT 13 extensions.
286 // We simply detect whether we're booting from CD by checking whether the drive
287 // number is >= 0x90. It's 0x90 on the Insyde BIOS, and 0x9F on most other BIOSes.
288 if (DriveNumber
>= 0x90)
290 LastSupported
= TRUE
;
294 LastDriveNumber
= DriveNumber
;
296 // IBM/MS INT 13 Extensions - INSTALLATION CHECK
299 // DL = drive (80h-FFh)
301 // CF set on error (extensions not supported)
302 // AH = 01h (invalid function)
303 // CF clear if successful
304 // BX = AA55h if installed
305 // AH = major version of extensions
307 // 20h = 2.0 / EDD-1.0
308 // 21h = 2.1 / EDD-1.1
311 // CX = API subset support bitmap
312 // DH = extension version (v2.0+ ??? -- not present in 1.x)
314 // Bitfields for IBM/MS INT 13 Extensions API support bitmap
315 // Bit 0, extended disk access functions (AH=42h-44h,47h,48h) supported
316 // Bit 1, removable drive controller functions (AH=45h,46h,48h,49h,INT 15/AH=52h) supported
317 // Bit 2, enhanced disk drive (EDD) functions (AH=48h,AH=4Eh) supported
318 // extended drive parameter table is valid
319 // Bits 3-15 reserved
321 RegsIn
.w
.bx
= 0x55AA;
322 RegsIn
.b
.dl
= DriveNumber
;
324 // Reset the disk controller
325 Int386(0x13, &RegsIn
, &RegsOut
);
327 if (!INT386_SUCCESS(RegsOut
))
329 // CF set on error (extensions not supported)
330 LastSupported
= FALSE
;
334 if (RegsOut
.w
.bx
!= 0xAA55)
336 // BX = AA55h if installed
337 LastSupported
= FALSE
;
341 if (!(RegsOut
.w
.cx
& 0x0001))
343 // CX = API subset support bitmap
344 // Bit 0, extended disk access functions (AH=42h-44h,47h,48h) supported
345 printf("Suspicious API subset support bitmap 0x%x on device 0x%lx\n", RegsOut
.w
.cx
, DriveNumber
);
346 LastSupported
= FALSE
;
350 LastSupported
= TRUE
;
354 BOOLEAN
PcDiskReadLogicalSectors(ULONG DriveNumber
, ULONGLONG SectorNumber
, ULONG SectorCount
, PVOID Buffer
)
357 DPRINTM(DPRINT_DISK
, "PcDiskReadLogicalSectors() DriveNumber: 0x%x SectorNumber: %I64d SectorCount: %d Buffer: 0x%x\n", DriveNumber
, SectorNumber
, SectorCount
, Buffer
);
360 // Check to see if it is a fixed disk drive
361 // If so then check to see if Int13 extensions work
362 // If they do then use them, otherwise default back to BIOS calls
364 if ((DriveNumber
>= 0x80) && PcDiskInt13ExtensionsSupported(DriveNumber
))
366 DPRINTM(DPRINT_DISK
, "Using Int 13 Extensions for read. PcDiskInt13ExtensionsSupported(%d) = %s\n", DriveNumber
, PcDiskInt13ExtensionsSupported(DriveNumber
) ? "TRUE" : "FALSE");
369 // LBA is easy, nothing to calculate
372 return PcDiskReadLogicalSectorsLBA(DriveNumber
, SectorNumber
, SectorCount
, Buffer
);
376 // LBA is not supported default to the CHS calls
377 return PcDiskReadLogicalSectorsCHS(DriveNumber
, SectorNumber
, SectorCount
, Buffer
);
384 PcDiskGetDriveGeometry(ULONG DriveNumber
, PGEOMETRY Geometry
)
390 DPRINTM(DPRINT_DISK
, "DiskGetDriveGeometry()\n");
392 /* BIOS Int 13h, function 08h - Get drive parameters
394 * DL = drive (bit 7 set for hard disk)
395 * ES:DI = 0000h:0000h to guard against BIOS bugs
399 * CF clear if successful
401 * AL = 00h on at least some BIOSes
402 * BL = drive type (AT/PS2 floppies only)
403 * CH = low eight bits of maximum cylinder number
404 * CL = maximum sector number (bits 5-0)
405 * high two bits of maximum cylinder number (bits 7-6)
406 * DH = maximum head number
407 * DL = number of drives
408 * ES:DI -> drive parameter table (floppies only)
411 RegsIn
.b
.dl
= DriveNumber
;
412 RegsIn
.w
.es
= 0x0000;
413 RegsIn
.w
.di
= 0x0000;
415 /* Get drive parameters */
416 Int386(0x13, &RegsIn
, &RegsOut
);
418 if (! INT386_SUCCESS(RegsOut
))
423 Cylinders
= (RegsOut
.b
.cl
& 0xC0) << 2;
424 Cylinders
+= RegsOut
.b
.ch
;
426 Geometry
->Cylinders
= Cylinders
;
427 Geometry
->Heads
= RegsOut
.b
.dh
+ 1;
428 Geometry
->Sectors
= RegsOut
.b
.cl
& 0x3F;
429 Geometry
->BytesPerSector
= 512; /* Just assume 512 bytes per sector */
435 PcDiskGetCacheableBlockCount(ULONG DriveNumber
)
439 /* If LBA is supported then the block size will be 64 sectors (32k)
440 * If not then the block size is the size of one track */
441 if (DiskInt13ExtensionsSupported(DriveNumber
))
445 /* Get the disk geometry
446 * If this fails then we will just return 1 sector to be safe */
447 else if (! PcDiskGetDriveGeometry(DriveNumber
, &Geometry
))
453 return Geometry
.Sectors
;