Commit Graph

50 Commits

Author SHA1 Message Date
John Baldwin
dfd89d691e Whoops, missed these bits in the previous commit. 2001-11-03 22:21:21 +00:00
John Baldwin
580d63df68 Add support for sending messages to the serial console which is helpful
when debugging boot problems.  It is not on by default but is enabled via
the BTX_SERIAL variable.  The port and speed can be set via the same
variables used by boot2 and the loader.
2001-11-03 22:09:30 +00:00
John Baldwin
0535c2bbad Add support for outputting multiple lines when dumping memory during the
register dump.  Change the default to bump 2 lines of output (32 bytes)
instead of 1 line (16 byte).
2001-11-03 21:53:46 +00:00
John Baldwin
5eef06c222 Add support for trace traps by returning from them just as for breakpoint
traps rather than halting.  Ideally, we should avoid printing the
'BTX halted' message for debug register dumps.
2001-11-03 21:42:25 +00:00
John Baldwin
25895accd8 Output a newline at the end of a dump so that there are blank lines between
dumps when using breakpoints or tracing.
2001-11-03 21:40:47 +00:00
Robert Nordier
816aa3c0b5 Unset MAINTAINER. 2001-07-21 14:32:47 +00:00
Robert Nordier
9dfe98e24e Fix reboot buglet when BOOT_BTX_NOHANG is defined.
Submitted by: Umesh Krishnaswamy <umesh@juniper.net>
2001-05-27 20:15:10 +00:00
John Baldwin
b833d157c7 Always disable paging when exiting back to real mode after receiving a
fatal trap.  Also, reload the GDT register to point to BTX's GDT before
playing around with the segment registers to return to real mode.  This is
helpful if the kernel causes a fatal exception before it has setup its own
IDT and fault handlers.  For example, if one happens to break mtx_init().
Without these changes BTX would recursively page fault (if paging was not
disabled) or triple fault and reset the CPU (without the GDT reload)
instead of providing a potentially useful register dump.

Reviewed by:	rnordier
2001-03-21 20:08:07 +00:00
Robert Nordier
ce6a6a0f90 Set MAINTAINER. 2000-10-02 17:23:16 +00:00
John Baldwin
6bd9abd49a Add a new compile-time tweak to BTX. If you set the make(1) variable
BOOT_BTX_NOHANG, then BTX will be compiled with the appropriate flags so
that it reboots after a fault instead of hanging forever.

Requested by:	ps
Approved by:	rnordier
2000-08-24 20:57:44 +00:00
John Baldwin
bd61ce880f Emulate the WBINVD instruction when it is called by the BIOS. 2000-07-06 00:13:21 +00:00
John Baldwin
0b74850760 Change the fault message to say 'BTX halted' isntead of 'System halted' to
avoid confusion.

Submitted by:	George Scott <George.Scott@its.monash.edu.au>
2000-06-29 08:24:50 +00:00
John Baldwin
52f5035190 Rework the detecting of the rdmsr and wrmsr instructions in the v86
monitor so that the codepath is cleaner and easier to maintain in the
future.
2000-06-29 01:25:31 +00:00
John Baldwin
1ddb0ab555 Add support for emulating the RDMSR and WRMSR instructions into BTX. In
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>
2000-06-17 06:45:40 +00:00
John Baldwin
e1efa49a84 Convert the short stub of real-mode code into 16-bit assembly. 2000-05-24 02:20:34 +00:00
John Baldwin
638bac9fc0 Clean up all of the 16-bit assembly code in the x86 bootstrap to work
with the new binutils.  Now that we have a decent assembler, all the old
m4 macros are no longer needed.  Instead, straight assembly can be used
since as(1) now understands 16-bit addressing, branches, etc.  Also,
several bugs have been fixed in as(1), allowing boot0.s to be further
cleaned up.
2000-05-23 12:18:49 +00:00
John Baldwin
36273c5d79 Don't disable interrupts when calling a vm86 mode interrupt or routine
from user mode.  Don't disable interrupts when returning from vm86 mode
to user mode either.  Now, we only disable interrupts before calling a
hardware interrupt handler, which is the only time we _should_ be
disabling interrupts.

Because of this, err, feature, any routine that one called in vm86 mode
had to re-enable interrupts by setting the interrupt flag or interrupts
would remain disabled even after the routine returned.  For example, I
have a simple debugging routine that uses a vm86 mode function to dump
any arbitrary memory word that I use to read the BIOS timer or any other
memory location.  This function does 1 load instruction from memory and
then returns.  Since it didn't re-enable interrupts, the first time I
called it to read the BIOS timer, it disabled interrupts.   This also
affected the PXE bootstrap as it needs interrupts enabled while it is
processing.  This patch fixes both of those situations so that those
functions do not worry about having to enable interrupts.  Hardware
interrupt handlers worked fine with the old code because they always
enable interrupts as part of their routine.

If you have any problems with the loader after this commit, please
let me know.  I'd like to MFC it in a week or two since PXE support
needs it.

Noticed by:	ps, Michael Johnston <michael.johnston@intel.com>
2000-04-26 04:35:25 +00:00
John Baldwin
48a0c4ea04 Mega i386 loader commit.
- Don't hard code 0x10000 as the entry point for the loader.  Instead add
  src/sys/boot/i386/Makefile.inc which defines a make variable with the
  entry point for the loader.  Move the loader's entry point up to
  0x20000, which makes PXE happy.
- Don't try to use cpp to parse btxldr for the optional BTXLDR_VERBOSE,
  instead use m4 to achieve this.  Also, add a BTXLDR_VERBOSE knob in the
  btxldr Makefile to turn this option on.
- Redo parts of cdldr's Makefile so that it now builds and installs cdboot
  instead of having i386/loader/Makefile do that.  Also, add in some more
  variables to make the pxeldr Makefile almost identical and thus to ease
  maintainability.
- Teach cdldr about the a.out format.  Cdldr now parsers the a.out header
  of the loader binary and relocates it based on that.  The entry point of
  the loader no longer has to be hardcoded into cdldr.  Also, the boot
  info table from mkisofs is no longer required to get a useful cdboot.
- Update the lsdev function for BIOS disks to parse other file systems
  (such as DOS FAT) that we currently support.  This is still buggy as
  it assumes that a floppy with a DOS boot sector actually has a MBR and
  parses it as such.  I'll be fixing this in the future.
- The biggie:  Add in support for booting off of PXE-enabled network
  adapters.  Currently, we use the TFTP API provided by the PXE BIOS.
  Eventually we will switch to using the low-level NIC driver thus
  allowing both TFTP and NFS to be used, but for now it's just TFTP.

Submitted by:	ps, alfred
Testing by:	Benno Rice <benno@netizen.com.au>
2000-03-28 01:19:53 +00:00
John Baldwin
536fcb08bf This patch to BTX fixes several small things:
1) Fix a bug in the int15 function 87 emulation where we only copied half
   of what the BIOS asked for.  This caused the Mylex RAID adapter to go
   haywire and start trashing memory when you tried to boot from it.
2) Don't use interrupt 19 to reboot.  Instead, set the reboot flag to a warm
   boot and jump to the BIOS's reboot handler.  int 19 doesn't clear memory
   or restore the interrupt vector table, and thus really isn't safe.  For
   example, when booting off of PXE, the PXE BIOS eats up a chunk of memory
   for its internal data and structures.  Since we rebooted via int 19,
   using the 'reboot' command in the loader resulted in that memory not
   being reclaimed by the BIOS.  Thus, after a few PXE boots, the system
   was out of lower memory.
3) Catch any int 19 calls made by a BTX client or a user pressing
   Ctrl-Alt-Delete and shutdown BTX and reboot the machine cleanly.  This
   fixes Ctrl-Alt-Delete in the loader and in boot2 instead of presenting
   the user with a BTX fault.

Approved by:	jkh
Found by:	1) by msmith
2000-02-16 07:00:16 +00:00
John Baldwin
c8bb85f758 Add the new cdldr CD bootstrap loader. This patch includes the following:
- Fix btxldr to preserve a NULL bootinfo pointer when it copies the kernel
  arguments.
- Add the cdldr bootstrap program.  This program is tacked onto the
  beginning of the standard 3rd stage boot loader (/boot/loader) to form
  the CD boot loader (/boot/cdboot).  When a CD is booted, the cdboot file
  is copied into memory instead and executed.  The cdldr stub emulates the
  environment normally provided by boot2 and then starts the loader.  This
  booting method does not emulate a floppy drive, but boots directly off of
  the CD.  This should fix the problems some BIOS's have with emulating a
  2.88 MB floppy image.
- Add support to the loader to recognize that it has been booted by cdldr
  instead of boot2 and use a simpler method of extracting the BIOS boot
  device.
2000-01-27 21:21:01 +00:00
John Baldwin
c299f41fd9 Fix brokenness introduced with the PAGING conditional variable. The value
of %cr0 wasn't reloaded into %eax before being modified to turn protected
mode off if PAGING was not defined.  The result was that the processor did
not exit protected mode, so when it tried to jump to segment 0x0 in the
next instruction to clear the prefetch cache like one should when leaving
protected mode, it actually tried to jump to a null selector, causing a
GPF.
2000-01-27 21:06:13 +00:00
John Baldwin
260c5d350e If PAGING is defined then actually turn it on when entering protected
mode.
1999-10-27 02:22:52 +00:00
John Baldwin
228ace6ebf aThis patch updates the BTX to emulate the BIOS function "Copy Extended
Memory" called as function 0x87 of interrupt 0x15.  Since the Mylex RAID
adapter's BIOS used this function to access memory (actually PCI bus
space) beyond 16 MB, this patch also allows BTX to address all 4 Gig of
possible address space on i386+.  Since the loader does not have room for
4 MB of page tables, this was done by turning off paging.

Paging was turned off via a compile time setting which defaults to off.
To enable paging, simply define the make variable PAGING.

rnordier might want to clean this up later.

Submitted by:	W. Gerald Hicks <wghicks@bellsouth.net>,
		Bosko Milekic <bmilekic@ares.dsuper.net>
Reviewed by:	msmith
Required by:	Mylex RAID adapter's BIOS
1999-10-12 21:33:49 +00:00
Brian Somers
ad128796fd Blank out the twiddly thing when outputting the ``BTX loader'' message. 1999-10-12 06:57:26 +00:00
Peter Wemm
c3aac50f28 $Id$ -> $FreeBSD$ 1999-08-28 01:08:13 +00:00
Robert Nordier
e2c9098e4f Drop some non-existent commented-out targets. 1999-05-18 22:10:05 +00:00
Robert Nordier
401d37631a Emulate a V86 "movl %cr0,%eax" instruction.
Feedback and testing: Kurt Hopfensperger <kjhmdjd@ix.netcom.com>
1999-02-25 16:27:41 +00:00
Robert Nordier
d7478bf0df Push version numbers up to 1.00. This is just intended to reflect
that the BTX code can be regarded as stable: there are no associated
code changes.

Suggested by: obrien
1999-01-22 13:07:17 +00:00
Robert Nordier
3d04f230e5 Revise a few comments. 1998-11-02 17:53:08 +00:00
Robert Nordier
3b1bd5ae35 Ignore, rather than emulate, an i386 'hlt' instruction (though for
most practical purposes, this should be indistinguishable from a
more strictly correct approach).

Feedback and testing: msmith
1998-11-01 13:52:52 +00:00
Mike Smith
4c1a7a5a8f Make the BTX loader much more quiet about what it's doing. This removes
most of the "what the (*^&%(*^ was that?" stuff that normally flies by.
1998-10-30 00:11:35 +00:00
Mike Smith
f41c619d3d Pop the return address off the stack before making a V86_CALLF call;
this allows us to implement what look like C function calls from user
space "directly" to v86 mode code.  (Used for calling the PnP BIOS)
1998-10-22 20:22:07 +00:00
Robert Nordier
8f65b6a695 Don't use an absolute path to objcopy.
Noticed by: Scott Mace <smace@intt.org>
1998-10-13 18:29:18 +00:00
Robert Nordier
10806461a7 Override for ELF. Override .s.o suffix rule. 1998-10-11 11:27:48 +00:00
Robert Nordier
b7b32c2745 Fix for "get base memory" bug found and mostly fixed by Mike. 1998-10-06 07:15:35 +00:00
Mike Smith
024e2ede72 The BIOS memory size is only a word. Some BIOSsen have garbage in the other
16 bits we were reading here, causing loss of arguments.
1998-10-06 06:13:36 +00:00
Robert Nordier
731a4a01db Adjust setting of argument pointer for BTX 0.87. 1998-10-04 21:15:45 +00:00
Robert Nordier
18577050a0 Allocate space for storing of arguments at the end of conventional
memory.
1998-10-04 21:14:33 +00:00
Robert Nordier
3948b979ba For system calls, reboot without prompting; for exceptions, display
message and await reset.
1998-10-03 18:05:12 +00:00
Robert Nordier
9cd66506dd Map all BTX system pages readable at ring 3.
This resolves the firmware problem first raised in connection
with PR 8105, although unrelated.
1998-10-03 14:33:06 +00:00
Mike Smith
9d38269bae Fix an egregious precedence bug. 1998-10-02 20:52:26 +00:00
Mike Smith
39de38225b Mark exit() as __attribute__((__noreturn__)) 1998-10-02 16:22:54 +00:00
Peter Wemm
c7f3e669b7 Make these compile when there is an obj dir. 1998-09-25 17:14:16 +00:00
Mike Smith
948486abe3 Initial integration of the i386 bootloader and BTX.
- Discard large amounts of BIOS-related code in favour of the more compact
   BTX vm86 interface.
 - Build the loader module as ELF, although the resulting object is a.out,
   make gensetdefs 32/64-bit sensitive and use a single copy of it.
 - Throw away installboot, as it's no longer required.
 - Use direct bcopy operations in the i386_copy module, as BTX
   maps the first 16M of memory.  Check operations against the
   detected size of actual memory.
1998-09-17 23:52:16 +00:00
Robert Nordier
ec3009d3ec Add exec syscall. 1998-09-15 13:26:23 +00:00
Mike Smith
0d5d0b20dc Resynch with working sources before BTX integration.
- Use format-independant module allocator.
 - Conditionalise ISA PnP support.
 - Simplify PnP enumerator interface.
 - Improve module/object searching.
 - Add missing depend/install targets in BTX makefiles.
 - Pass the kernel environment and module data in extended bootinfo fields.
 - Add a pointer to the end of the kernel + modules in bootinfo.
 - Fix parsing of old-style kernel arguments.
1998-09-14 18:27:06 +00:00
Robert Nordier
4cbf0238eb Add BTX startup/interface code. 1998-09-14 10:37:00 +00:00
Robert Nordier
38c931abc7 Enable client entry point support. 1998-09-13 13:28:07 +00:00
Robert Nordier
b0923a2edc Add btxldr, a BTX loader for ELF clients. 1998-09-12 06:30:26 +00:00
Robert Nordier
aa7af79537 BTX (aka the boot extender) is an i386 kernel that hosts 32-bit
bootstrap programs, and provides page-level protection, hardware
interrupt reflection, a virtual-8086 mode interface to BIOS, etc.
1998-09-12 04:29:23 +00:00