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Add LBA support

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This commit is contained in:
gord 1999-03-04 04:31:30 +00:00
parent 17b6dcd892
commit 5223272174
8 changed files with 147 additions and 32 deletions
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23
ChangeLog
View file

@ -1,3 +1,26 @@
1999-03-03 Gordon Matzigkeit <gord@trick.fig.org>
* shared_src/asm.S (biosdisk): Use LBA mode if high nibble of
GEOMETRY is nonzero.
(get_diskinfo): Set high nibble of GEOMETRY (0xf0000000) to 1 if
LBA mode is detected.
1999-03-02 Gordon Matzigkeit <gord@trick.fig.org>
* shared_src/disk_io.c (make_saved_active): Use BIOSDISK_READ and
BIOSDISK_WRITE.
* shared_src/cmdline.c (enter_cmdline): Use BIOSDISK_WRITE.
* shared_src/shared.h (BIOSDISK_SUBFUNC_READ,
BIOSDISK_SUBFUNC_WRITE): Delete constants.
* shared_src/asm.S (biosdisk): Change subfunc argument to be
read=0, write=1.
* configure.in: Drop redundant AC_PROG_INSTALL. From OKUJI
Yoshinori.
1999-03-01 Gordon Matzigkeit <gord@trick.fig.org>
* debian/rules (binary-arch): Properly install README.debian.

1
NEWS
View file

@ -3,6 +3,7 @@ NEWS - list of user-visible changes between releases of GRUB
New in 0.5.90 - 1999-03-01, Gordon Matzigkeit:
* Bug fixes.
* GRUB understands symlinks on ext2fs (but still not ffs).
* The GRUB stage2 uses LBA mode and AWARD extensions if they are supported.
* Many source code and build cleanups to comply with GNU standards.
New in 0.5 - 1998-08-20, Erich Boleyn:

1
configure.in
View file

@ -43,7 +43,6 @@ AC_SUBST(stage2debug)
# Programs
#
AC_PROG_INSTALL
AC_CHECK_TOOL(CC, gcc)
AC_CHECK_TOOL(LD, ld)
AC_CHECK_TOOL(OBJCOPY, objcopy)

6
debian/changelog vendored
View file

@ -1,3 +1,9 @@
grub (0.5.91) unstable; urgency=low
* Added support for LBA mode and BIOS extensions.
--
grub (0.5.90) unstable; urgency=low
* Beta-testing release.

129
shared_src/asm.S
View file

@ -330,15 +330,13 @@ realcseg:
/*
* biosdisk(subfunc, drive, geometry, sector, nsec, segment)
* biosdisk(write, drive, geometry, sector, nsec, segment)
* Read/write "nsec" sectors from disk to real segment "segment"
* offset zero
*
* If it will fit into the BIOS geometry, it tries the INT 0x13
* AH=<subfunction> interface, else if it is a hard disk, it will
* try the hard disk LBA calls (not yet implemented). If these
* won't work, or otherwise it is out of the translated area, then
* it returns BIOS_GEOMETRY_ERROR.
* Will try INT 0x13 LBA (AH=0x42/0x43) or standard (AH=0x2/0x3)
* depending on probed geometry. For addresses out of the translated
* area, it returns BIOS_GEOMETRY_ERROR.
*/
ENTRY(biosdisk)
@ -350,10 +348,56 @@ ENTRY(biosdisk)
push %edx
push %esi
/* Check whether we have LBA. */
movb 0x13(%ebp), %al
shrb $4, %al
jz disk_compute_args /* nope. */
/* set up disk address packet for extended calls (LBA mode) */
movl 0x14(%ebp), %eax /* absolute block number */
movl %eax, dap_block
xorl %eax, %eax
movl %eax, dap_block + 4
movb 0x18(%ebp), %al /* number of sectors */
movw %ax, dap_blocks
/* set up the buffer address */
xorl %eax, %eax
movw 0x1c(%ebp), %ax /* segment */
shll $4, %eax
movl %eax, dap_buffer
movl $disk_address_packet, %esi
xorb %bl, %bl
movb 0x8(%ebp), %bh /* read=0, write=1 */
addb $0x42, %bh /* convert to extended subfunction */
movb 0xc(%ebp), %dl /* drive */
call EXT_C(prot_to_real) /* enter real mode */
.code16
movw %bx, %ax
int $0x13 /* do the operation */
/* set success return value */
movb $0, %bl
/* did we actually succeed? */
data32
jnc disk_exit_16
data32
call EXT_C(real_to_prot) /* back to protected mode */
.code32
/* either failed, or a floppy, so try standard BIOS calls */
disk_compute_args:
/*
* "geometry" is a longword representing the BIOS geometry:
* 6 bit zero
* 10 bit cylinder (bytes 2 & 3)
* GEOMETRY is a longword representing the BIOS geometry:
* 4 bit BIOS extension (0 = none, 1 = LBA)
* 12 bit cylinder (bytes 2 & 3)
* 8 bit head (byte 1)
* 8 bit sector (byte 0)
*/
@ -379,15 +423,27 @@ ENTRY(biosdisk)
/* check cylinder offset, is there a geometry problem here? */
movl 0x10(%ebp), %ebx
shrl $16, %ebx
andb $0xf, %bh /* mask out bios extension code */
cmpl %ebx, %eax
/* if not, go on to standard read function */
jle disk_use_standard_bios
/* XXX else we better use LBA or generate a geometry error */
movl $BIOSDISK_ERROR_GEOMETRY, %eax
jmp disk_exit_32
disk_address_packet:
.align 4
.byte 0x20 /* length of packet */
.byte 0 /* reserved */
dap_blocks:
.word 0 /* number of blocks */
dap_buffer:
.long 0 /* buffer address */
dap_block:
.long 0 /* absolute block number */
.long 0
/*
* This portion implements the BIOS standardized
* INT 0x13/AH=<subfunc> interface.
@ -396,9 +452,10 @@ disk_use_standard_bios:
shll $8, %edx /* get head number to %dh */
xchgl %eax, %ecx /* cylinder to %cx, sector to %al */
/* cylinder; the highest 2 bits of cyl is in %cl */
/* FIXME: cylinder; bits 10,11 of cyl are in %dh */
/* cylinder; bits 8,9 of cyl are in %cl */
xchgb %ch, %cl
rorb $2, %cl
shlb $6, %cl
incb %al /* sector; sec starts from 1, not 0 */
orb %al, %cl
movb 0xc(%ebp), %dl /* drive */
@ -406,7 +463,8 @@ disk_use_standard_bios:
/* prot_to_real will set %es to 0, so must set it ourselves
after it is called */
movb 0x18(%ebp), %bl /* number of sectors */
movb 0x8(%ebp), %bh /* bios disk subfunction */
movb 0x8(%ebp), %bh /* read=0, write=1 */
addb $0x2, %bh /* convert to subfunction */
shll $16, %ebx /* shift num sect. and subfunction */
movw 0x1c(%ebp), %bx /* segment */
@ -528,6 +586,7 @@ probe_loop:
movb $1, %dh
movb $79, %ch
xorb %bh, %bh /* no BIOS extensions */
data32
jmp probe_success
@ -535,7 +594,27 @@ probe_values:
.byte 36, 18, 15, 9, 0
hard_drive:
movb $0x8, %ah /* ask for disk info */
/* Check for LBA. */
movb $0x41, %ah
movw $0x55aa, %bx
int $0x13 /* int 13 extensions install check */
data32
jc 1f /* invalid function */
cmpw $0xaa55, %bx
data32
jnz 1f /* failed magic */
andb $1, %cx
data32
jnz 1f /* LBA not supported */
/* Wahoo! Got LBA! */
movb $0x1, %bh
jmp 2f
1: xorb %bh, %bh /* Too bad, no LBA */
2: movb $0x8, %ah /* ask for disk info */
int $0x13
data32
@ -546,18 +625,24 @@ hard_drive:
probe_success:
/*
* form a longword representing all this gunk:
* 6 bit zero
* 10 bit cylinder
* form a dword representing all this gunk:
* 4 bit BIOS extension (0 = none, 1 = LBA)
* 12 bit cylinder
* 8 bit head
* 8 bit sector
*/
movb %cl, %al /* Upper two bits of cylinder count */
andl $192,%eax
addr32
leal 0(,%eax,4),%eax /* << 2 */
movb %bh, %ah /* restore BIOS extensions bits */
movb %dh, %al /* bits 10,11 of cylinder count */
andb $0xc0, %eax
shlw $2, %ax /* << 2 */
movb %cl, %al /* bits 8,9 of cylinder count */
andb $0xc0, %al
shlw $2, %ax /* << 2 */
movb %ch, %al /* Lower 8 bits */
sall $16,%eax /* << 16 */
shll $16, %eax /* << 16 */
andb $0x3f, %ah /* mask of cylinder gunk */
movb %dh, %ah /* max head */
andb $0x3f, %cl /* mask of cylinder gunk */
movb %cl, %al /* max sector (and # sectors) */

4
shared_src/cmdline.c
View file

@ -450,11 +450,11 @@ returnit:
buf_track = -1;
if (!errnum
&& (biosdisk(BIOSDISK_SUBFUNC_WRITE,
&& (biosdisk(BIOSDISK_WRITE,
dest_drive, dest_geom,
dest_sector, 1, (BOOTSEC_LOCATION>>4))
|| (write_stage2_sect
&& biosdisk(BIOSDISK_SUBFUNC_WRITE,
&& biosdisk(BIOSDISK_WRITE,
current_drive, buf_geom,
stage2_sect, 1, SCRATCHSEG))))
errnum = ERR_WRITE;

7
shared_src/disk_io.c
View file

@ -86,6 +86,7 @@ rawread (int drive, int sector, int byte_offset, int byte_len, int addr)
if (buf_drive != drive)
{
buf_geom = get_diskinfo (drive);
printf ("buf_geom = 0x%x\n", buf_geom); /* FIXME */
buf_drive = drive;
buf_track = -1;
}
@ -118,7 +119,7 @@ rawread (int drive, int sector, int byte_offset, int byte_len, int addr)
bufaddr = BUFFERADDR + byte_offset;
}
if (bios_err = biosdisk (BIOSDISK_SUBFUNC_READ, drive, buf_geom,
if (bios_err = biosdisk (BIOSDISK_READ, drive, buf_geom,
read_start, read_len, BUFFERSEG))
{
buf_track = -1;
@ -132,7 +133,7 @@ rawread (int drive, int sector, int byte_offset, int byte_len, int addr)
* required sector(s) rather than failing completely.
*/
if (slen > num_sect
|| biosdisk (BIOSDISK_SUBFUNC_READ, drive, buf_geom,
|| biosdisk (BIOSDISK_READ, drive, buf_geom,
sector, slen, BUFFERSEG))
errnum = ERR_READ;
@ -270,7 +271,7 @@ make_saved_active (void)
buf_track = -1;
if (biosdisk (BIOSDISK_SUBFUNC_WRITE, saved_drive, buf_geom,
if (biosdisk (BIOSDISK_WRITE, saved_drive, buf_geom,
0, 1, SCRATCHSEG))
{
errnum = ERR_WRITE;

6
shared_src/shared.h
View file

@ -48,8 +48,8 @@
/*
* BIOS disk defines
*/
#define BIOSDISK_SUBFUNC_READ 0x2
#define BIOSDISK_SUBFUNC_WRITE 0x3
#define BIOSDISK_READ 0x0
#define BIOSDISK_WRITE 0x1
#define BIOSDISK_ERROR_GEOMETRY 0x100
/*
@ -287,7 +287,7 @@ __attribute__ ((noreturn));
/* low-level disk I/O */
int get_diskinfo (int drive);
int biosdisk (int subfunc, int drive, int geometry,
int biosdisk (int read, int drive, int geometry,
int sector, int nsec, int segment);
void stop_floppy (void);