to 0x600 via a 'rep movsw'. Once that was done, %cx was zero, so we could
simply use 'movb' to update the lower byte of %cx in preparation for
zeroing out the fake partition entry used to boot to other drives via F5.
Well, in the new boot0, we don't actually relocate ourselves, instead it
is easier to create the fake partition entry first and then just use it to
get the BIOS to load all of boot0 into memory at 0x600. However, since we
aren't doing the relocate code anymore, we don't know that %cx == 0 when
we hit the 'movb' to setup %cx for clearning the fake partition entry.
Thus, if %ch != 0 when the BIOS started boot0, then it would end up zeroing
a lot more memory than just 8 words. The solution is to do a word move of
$8 into %cx.
Debugging help from: David Wolfskill <dhw@whistle.com>
<stand.h>. Also, since bcache_strategy() used to not have a prototype,
arcdisk happily called bcache_strategy() with 6 parameters instead of 7,
leaving out the disk unit number, which is the 2nd parameter. Add in the
unit number to the bcache_strategy() call to fix this.
sector 0 of a disk and boot0.5 is the `boot selector' which starts
from address 0x400. The IPL loads boot0.5 and boot0.5 loads bootblock
of a slice.
The boot manager stuff was developed by me (kato) with Borland C++,
and then, translated into bcc in the ports collection by Nokubi-san.
After that, boot0 has been translated into gas with the .code16
directive by Takahashi-san (nyan) and boot0.5 has been rewritten in
gas by me.
Linux kernel image, and is designed to be dropped into a Linux system
and booted via LILO. Once booted, the user is greeted by the FreeBSD
loader. This still isn't quite complete, as the the root= specification
from LILO isn't currently passed to the loader yet.
- Autodetection and support of the BIOS EDD extensions to work around the
1024 cylinder limit on all but really ancient BIOS's.
- To work around some BIOS's which break when EDD is used with older drives,
we only attempt to use EDD if the cylinder is > 1023.
- Since this new code required more space than we had left, expand boot0 to
2 sectors (1024 bytes) in length.
- Add support for boot0 being multiple sectors using predefined constants.
If boot0 needs to be extended in the future, all that is required is
bumping the NUM_SECTORS constant.
- Now that we have more room to work with, add a few more fs type
descriptions while making others more verbose.
only doing so if loader.rc does not exist. This fixes the problem where
installworld doesn't update /boot/loader.4th, resulting in device.hints not
being loaded after updating past the config(8) changes, which resulted in
mcclock0 not being probed, and a nice kernel panic during boot.
use the BIOS Equipment List to determine how many hard drives are
installed and if the drive number we received in %dl is valid.
- Don't bother to disable interrupts when setting up the stack. The 8086
and beyond implicitly disable interrupts after an instruction that sets
%ss (for example, a pop or a mov) so that you can safely set %ss and %sp
in two consecutive instructions. An exception to this is the lss
instruction, which can set both registers simultaneously and thus doesn't
need this hack.
- Add support for EDD BIOS extensions to support booting off of hard drives
of nearly arbitrary length.
- Add in support for the EDD (Enhanced Disk Drive) BIOS extensions to
use LBA mode for accessing drives past cylinder 1024. This should allow
us to load a kernel from anywhere on a newer drive up to 2 TB. Part
of this came from the PR below.
PR: i386/13847
Submitted by: Tor Egge <Tor.Egge@fast.no>
theory, this should allow the K7V Athlon motherboard to boot ok with boot
virus protection enabled. However, I have no hardware to test this. It
shouldn't break anything though. :)
Prodded by: Kelly Yancey <kbyanc@posi.net>
no clue.
Set sourceid to 0 when booting, which is the correct setting for stdin.
Set sourceid to an arbitrary fd when include'ing, preserving and restoring
the previous sourceid. This is possibly broken(), as 0 is a valid fd. Maybe
we should +1 to this value.
This fixes the version problem widely reported.
is failing for everybody that I have spoken with that has tried it.
FreeBSD/i386 bootstrap loader, Revision 0.8
(root@outback.netplex.com.au, Tue Jun 13 23:26:49 PDT 2000)
Loader version 0.3+ required
Aborted!
start not found
Note that the 0.3+ message is from inside the arch-alpha block, not the
i386 block of code. And even then, 0.8 is higher than 0.3.
This prevents the rest of the loader.conf stuff working. :-/
Use Warner Losh's "hint" driver to decode ascii strings to fill the
resource table at boot time.
config(8) no longer generates an ioconf.c table - ie: the configuration
no longer has to be compiled into the kernel. You can reconfigure your
isa devices with the likes of this at loader(8) time:
set hint.ed.0.port=0x320
userconfig will be rewritten to use this style interface one day and will
move to /boot/userconfig.4th or something like that.
It is still possible to statically compile in a set of hints into a kernel
if you do not wish to use loader(8). See the "hints" directive in GENERIC
as an example.
All device wiring has been moved out of config(8). There is a set of
helper scripts (see i386/conf/gethints.pl, and the same for alpha and pc98)
that extract the 'at isa? port foo irq bar' from the old files and produces
a hints file. If you install this file as /boot/device.hints (and update
/boot/defaults/loader.conf - You can do a build/install in sys/boot) then
loader will load it automatically for you. You can also compile in the
hints directly with: hints "device.hints" as well.
There are a few things that I'm not too happy with yet. Under this scheme,
things like LINT would no longer be useful as "documentation" of settings.
I have renamed this file to 'NOTES' and stored the example hints strings
in it. However... this is not something that config(8) understands, so
there is a script that extracts the build-specific data from the
documentation file (NOTES) to produce a LINT that can be config'ed and
built. A stack of man4 pages will need updating. :-/
Also, since there is no longer a difference between 'device' and
'pseudo-device' I collapsed the two together, and the resulting 'device'
takes a 'number of units' for devices that still have it statically
allocated. eg: 'device fe 4' will compile the fe driver with NFE set
to 4. You can then set hints for 4 units (0 - 3). Also note that
'device fe0' will be interpreted as "zero units of 'fe'" which would be
bad, so there is a config warning for this. This is only needed for
old drivers that still have static limits on numbers of units.
All the statically limited drivers that I could find were marked.
Please exercise EXTREME CAUTION when transitioning!
Moral support by: phk, msmith, dfr, asmodai, imp, and others
