source: bootcd/isolinux/syslinux-6.03/gpxe/src/arch/i386/include/int13.h

Last change on this file was e16e8f2, checked in by Edwin Eefting <edwin@datux.nl>, 3 years ago

bootstuff
  • Property mode set to 100644
File size: 7.3 KB
Line 
1#ifndef INT13_H
2#define INT13_H
3
4/** @file
5 *
6 * INT 13 emulation
7 *
8 */
9
10FILE_LICENCE ( GPL2_OR_LATER );
11
12#include <stdint.h>
13#include <gpxe/list.h>
14#include <realmode.h>
15
16struct block_device;
17
18/**
19 * @defgroup int13ops INT 13 operation codes
20 * @{
21 */
22
23/** Reset disk system */
24#define INT13_RESET                     0x00
25/** Get status of last operation */
26#define INT13_GET_LAST_STATUS           0x01
27/** Read sectors */
28#define INT13_READ_SECTORS              0x02
29/** Write sectors */
30#define INT13_WRITE_SECTORS             0x03
31/** Get drive parameters */
32#define INT13_GET_PARAMETERS            0x08
33/** Get disk type */
34#define INT13_GET_DISK_TYPE             0x15
35/** Extensions installation check */
36#define INT13_EXTENSION_CHECK           0x41
37/** Extended read */
38#define INT13_EXTENDED_READ             0x42
39/** Extended write */
40#define INT13_EXTENDED_WRITE            0x43
41/** Get extended drive parameters */
42#define INT13_GET_EXTENDED_PARAMETERS   0x48
43/** Get CD-ROM status / terminate emulation */
44#define INT13_CDROM_STATUS_TERMINATE    0x4b
45
46/** @} */
47
48/**
49 * @defgroup int13status INT 13 status codes
50 * @{
51 */
52
53/** Operation completed successfully */
54#define INT13_STATUS_SUCCESS            0x00
55/** Invalid function or parameter */
56#define INT13_STATUS_INVALID            0x01
57/** Read error */
58#define INT13_STATUS_READ_ERROR         0x04
59/** Write error */
60#define INT13_STATUS_WRITE_ERROR        0xcc
61
62/** @} */
63
64/** Block size for non-extended INT 13 calls */
65#define INT13_BLKSIZE 512
66
67/** An INT 13 emulated drive */
68struct int13_drive {
69        /** List of all registered drives */
70        struct list_head list;
71
72        /** Underlying block device */
73        struct block_device *blockdev;
74
75        /** BIOS in-use drive number (0x80-0xff) */
76        unsigned int drive;
77        /** BIOS natural drive number (0x80-0xff)
78         *
79         * This is the drive number that would have been assigned by
80         * 'naturally' appending the drive to the end of the BIOS
81         * drive list.
82         *
83         * If the emulated drive replaces a preexisting drive, this is
84         * the drive number that the preexisting drive gets remapped
85         * to.
86         */
87        unsigned int natural_drive;
88
89        /** Number of cylinders
90         *
91         * The cylinder number field in an INT 13 call is ten bits
92         * wide, giving a maximum of 1024 cylinders.  Conventionally,
93         * when the 7.8GB limit of a CHS address is exceeded, it is
94         * the number of cylinders that is increased beyond the
95         * addressable limit.
96         */
97        unsigned int cylinders;
98        /** Number of heads
99         *
100         * The head number field in an INT 13 call is eight bits wide,
101         * giving a maximum of 256 heads.  However, apparently all
102         * versions of MS-DOS up to and including Win95 fail with 256
103         * heads, so the maximum encountered in practice is 255.
104         */
105        unsigned int heads;
106        /** Number of sectors per track
107         *
108         * The sector number field in an INT 13 call is six bits wide,
109         * giving a maximum of 63 sectors, since sector numbering
110         * (unlike head and cylinder numbering) starts at 1, not 0.
111         */
112        unsigned int sectors_per_track;
113
114        /** Status of last operation */
115        int last_status;
116};
117
118/** An INT 13 disk address packet */
119struct int13_disk_address {
120        /** Size of the packet, in bytes */
121        uint8_t bufsize;
122        /** Reserved, must be zero */
123        uint8_t reserved;
124        /** Block count */
125        uint16_t count;
126        /** Data buffer */
127        struct segoff buffer;
128        /** Starting block number */
129        uint64_t lba;
130        /** Data buffer (EDD-3.0 only) */
131        uint64_t buffer_phys;
132} __attribute__ (( packed ));
133
134/** INT 13 disk parameters */
135struct int13_disk_parameters {
136        /** Size of this structure */
137        uint16_t bufsize;
138        /** Flags */
139        uint16_t flags;
140        /** Number of cylinders */
141        uint32_t cylinders;
142        /** Number of heads */
143        uint32_t heads;
144        /** Number of sectors per track */
145        uint32_t sectors_per_track;
146        /** Total number of sectors on drive */
147        uint64_t sectors;
148        /** Bytes per sector */
149        uint16_t sector_size;
150       
151} __attribute__ (( packed ));
152
153/**
154 * @defgroup int13types INT 13 disk types
155 * @{
156 */
157
158/** No such drive */
159#define INT13_DISK_TYPE_NONE    0x00
160/** Floppy without change-line support */
161#define INT13_DISK_TYPE_FDD     0x01
162/** Floppy with change-line support */
163#define INT13_DISK_TYPE_FDD_CL  0x02
164/** Hard disk */
165#define INT13_DISK_TYPE_HDD     0x03
166
167/** @} */
168
169/**
170 * @defgroup int13flags INT 13 disk parameter flags
171 * @{
172 */
173
174/** DMA boundary errors handled transparently */
175#define INT13_FL_DMA_TRANSPARENT 0x01
176/** CHS information is valid */
177#define INT13_FL_CHS_VALID       0x02
178/** Removable drive */
179#define INT13_FL_REMOVABLE       0x04
180/** Write with verify supported */
181#define INT13_FL_VERIFIABLE      0x08
182/** Has change-line supported (valid only for removable drives) */
183#define INT13_FL_CHANGE_LINE     0x10
184/** Drive can be locked (valid only for removable drives) */
185#define INT13_FL_LOCKABLE        0x20
186/** CHS is max possible, not current media (valid only for removable drives) */
187#define INT13_FL_CHS_MAX         0x40
188
189/** @} */
190
191/**
192 * @defgroup int13exts INT 13 extension flags
193 * @{
194 */
195
196/** Extended disk access functions supported */
197#define INT13_EXTENSION_LINEAR          0x01
198/** Removable drive functions supported */
199#define INT13_EXTENSION_REMOVABLE       0x02
200/** EDD functions supported */
201#define INT13_EXTENSION_EDD             0x04
202
203/** @} */
204
205/**
206 * @defgroup int13vers INT 13 extension versions
207 * @{
208 */
209
210/** INT13 extensions version 1.x */
211#define INT13_EXTENSION_VER_1_X         0x01
212/** INT13 extensions version 2.0 (EDD-1.0) */
213#define INT13_EXTENSION_VER_2_0         0x20
214/** INT13 extensions version 2.1 (EDD-1.1) */
215#define INT13_EXTENSION_VER_2_1         0x21
216/** INT13 extensions version 3.0 (EDD-3.0) */
217#define INT13_EXTENSION_VER_3_0         0x30
218
219/** @} */
220
221/** Bootable CD-ROM specification packet */
222struct int13_cdrom_specification {
223        /** Size of packet in bytes */
224        uint8_t size;
225        /** Boot media type */
226        uint8_t media_type;
227        /** Drive number */
228        uint8_t drive;
229        /** CD-ROM controller number */
230        uint8_t controller;
231        /** LBA of disk image to emulate */
232        uint32_t lba;
233        /** Device specification */
234        uint16_t device;
235        /** Segment of 3K buffer for caching CD-ROM reads */
236        uint16_t cache_segment;
237        /** Load segment for initial boot image */
238        uint16_t load_segment;
239        /** Number of 512-byte sectors to load */
240        uint16_t load_sectors;
241        /** Low 8 bits of cylinder number */
242        uint8_t cyl;
243        /** Sector number, plus high 2 bits of cylinder number */
244        uint8_t cyl_sector;
245        /** Head number */
246        uint8_t head;
247} __attribute__ (( packed ));
248
249/** A C/H/S address within a partition table entry */
250struct partition_chs {
251        /** Head number */
252        uint8_t head;
253        /** Sector number, plus high 2 bits of cylinder number */
254        uint8_t cyl_sector;
255        /** Low 8 bits of cylinder number */
256        uint8_t cyl;
257} __attribute__ (( packed ));
258
259#define PART_HEAD(chs) ( (chs).head )
260#define PART_SECTOR(chs) ( (chs).cyl_sector & 0x3f )
261#define PART_CYLINDER(chs) ( (chs).cyl | ( ( (chs).cyl_sector & 0xc0 ) << 2 ) )
262
263/** A partition table entry within the MBR */
264struct partition_table_entry {
265        /** Bootable flag */
266        uint8_t bootable;
267        /** C/H/S start address */
268        struct partition_chs chs_start;
269        /** System indicator (partition type) */
270        uint8_t type;
271        /** C/H/S end address */
272        struct partition_chs chs_end;
273        /** Linear start address */
274        uint32_t start;
275        /** Linear length */
276        uint32_t length;
277} __attribute__ (( packed ));
278
279/** A Master Boot Record */
280struct master_boot_record {
281        uint8_t pad[446];
282        /** Partition table */
283        struct partition_table_entry partitions[4];
284        /** 0x55aa MBR signature */
285        uint16_t signature;
286} __attribute__ (( packed ));
287
288extern void register_int13_drive ( struct int13_drive *drive );
289extern void unregister_int13_drive ( struct int13_drive *drive );
290extern int int13_boot ( unsigned int drive );
291
292#endif /* INT13_H */
Note: See TracBrowser for help on using the repository browser.