on i386 and amd64 machines. The overall process is that /boot/pmbr lives
in the PMBR (similar to /boot/mbr for MBR disks) and is responsible for
locating and loading /boot/gptboot. /boot/gptboot is similar to /boot/boot
except that it groks GPT rather than MBR + bsdlabel. Unlike /boot/boot,
/boot/gptboot lives in its own dedicated GPT partition with a new
"FreeBSD boot" type. This partition does not have a fixed size in that
/boot/pmbr will load the entire partition into the lower 640k. However,
it is limited in that it can only be 545k. That's still a lot better than
the current 7.5k limit for boot2 on MBR. gptboot mostly acts just like
boot2 in that it reads /boot.config and loads up /boot/loader. Some more
details:
- Include uuid_equal() and uuid_is_nil() in libstand.
- Add a new 'boot' command to gpt(8) which makes a GPT disk bootable using
/boot/pmbr and /boot/gptboot. Note that the disk must have some free
space for the boot partition.
- This required exposing the backend of the 'add' function as a
gpt_add_part() function to the rest of gpt(8). 'boot' uses this to
create a boot partition if needed.
- Don't cripple cgbase() in the UFS boot code for /boot/gptboot so that
it can handle a filesystem > 1.5 TB.
- /boot/gptboot has a simple loader (gptldr) that doesn't do any I/O
unlike boot1 since /boot/pmbr loads all of gptboot up front. The
C portion of gptboot (gptboot.c) has been repocopied from boot2.c.
The primary changes are to parse the GPT to find a root filesystem
and to use 64-bit disk addresses. Currently gptboot assumes that the
first UFS partition on the disk is the / filesystem, but this algorithm
will likely be improved in the future.
- Teach the biosdisk driver in /boot/loader to understand GPT tables.
GPT partitions are identified as 'disk0pX:' (e.g. disk0p2:) which is
similar to the /dev names the kernel uses (e.g. /dev/ad0p2).
- Add a new "freebsd-boot" alias to g_part() for the new boot UUID.
MFC after: 1 month
Discussed with: marcel (some things might still change, but am committing
what I have so far)
on duplicated code and support 64-bit LBAs for GPT.
- The code to manage an EDD or C/H/S I/O request are now in their own
routines. The EDD routine now handles a full 64-bit LBA instead of
truncating LBAs to the lower 32-bits. (MBRs and BSD labels only
have 32-bit LBAs anyway, so the only LBAs ever passed down were 32-bit).
- All of the bounce buffer and retry logic duplicated in bd_read() and
bd_write() are merged into a single bd_io() routine that takes an
extra direction argument. bd_read() and bd_write() are now simple
wrappers around bd_io().
- If a disk supports EDD then always use it rather than only using it if
the cylinder is > 1023. Other parts of the boot code already do
something similar to this. Also, GPT just uses LBAs, so for a GPT disk
it's probably best to ignore C/H/S completely. Always using EDD when
it is supported by a disk is an easy way to accomplish this.
MFC after: 1 week
macros to treat the 'slice' field as a real part of the bootdev instead
of as hack that spans two other fields (adaptor (sic) and controller)
that are not used in any modern FreeBSD boot code.
MFC after: 1 week
It is disabled by default. You need to put
LOADER_FIREWIRE_SUPPORT=yes in /etc/make.conf
and rebuild loader to enable it.
(cd /sys/boot/i386 && make clean && make && make install)
You can find a short introduction of dcons at
http://wiki.freebsd.org/DebugWithDcons
bioscom is called to set up serial port parameters because COMSPEED
was treated as an address instead of an immediate value, causing
serial port parameters to never be set.
PR: i386/110828
Reviewed by: jhb
MFC after: 2 weeks
I created and tested this with a custom FreeSBIE cd-image.
PR: i386/96452
Submitted by: Yuichiro Goto <y7goto at gmail dot com>
MFC after: 3 days
Approved by: imp (mentor)
rather than treating them as a fatal exception and halting. At least one
storage BIOS (some newer mpt(4) parts) have a breakpoint instruction in
their disk read routine.
MFC after: 3 days
to get the physical address doesn't work for all values of KVA_PAGES,
while masking 8 MSBs works for all values of KVA_PAGES that are
multiple of 4 for non-PAE and 8 for PAE. (This leaves us limited
with 12MB for non-PAE kernels and 14MB for PAE kernels.)
To get things right, we'd need to subtract the KERNBASE from the
virtual address (but KERNBASE is not easy to figure out from here),
or have physical addresses set properly in the ELF headers.
Discussed with: jhb
device (kind) specific unit field to the common field. This change
allows a future version of libefi to work without requiring anything
more than what is defined in struct devdesc and as such makes it
possible to compile said version of libefi for different platforms
without requiring that those platforms have identical derivatives
of struct devdesc.
are no longer limited to a virtual address space of 16 megabytes,
only mask high two bits of a virtual address. This allows to load
larger kernels (up to 1 gigabyte). Not masking addresses at all
was a bad idea on machines with less than >3G of memory -- kernels
are linked at 0xc0xxxxxx, and that would attempt to load a kernel
at above 3G. By masking only two highest bits we stay within the
safe limits while still allowing to boot larger kernels.
(This is a safer reimplmentation of sys/boot/i386/boot2/boot.2.c
rev. 1.71.)
Prodded by: jhb
Tested by: nyan (pc98)
commits. For some reason I thought the scale factor was a shift count
rather than the multiplicand (that is, I thought leal (%eax,%edx,4) was
going to generate %eax + %edx << 4 rather than %eax + %edx * 4). What
I need is to multiply by 16 to convert a real-mode (seg, offset) tuple
into a flat address. However, the max multiplicand for scaled/index
addressing on i386 is 8, so go back to using a shl and an add.
- Convert two more inter-register mov instructions where we don't need to
preserve the source register to xchg instructions to keep our space
savings.
Tested by: Ian FREISLICH if at hetzner.co.za
MFC after: 1 week
another 16 bytes off of BTX (and thus boot2):
- Compare against the value of %eax that is saved on the stack instead of
loading it into %eax (which requires saving the current %eax on the
stack).
- Use %ch to examine the keyboard flag state in the BIOS to see if
Ctrl-Alt-Del is pressed instead of %al so we don't have to save %eax on
the stack anymore.
MFC after: 1 week
BTX (and thus boot2):
- Don't bother saving %eax, %ebx, or %ecx as it is not necessary.
- Use a more compact sequence to load the base value out of a GDT entry
by loading the contiguous low 24 bits into the upper 24 bits of %eax,
loading the high 8 bits into %al, and using a ror to rotate the bits
(2 mov's and a ror) rather than loading the pieces in smaller chunks
(3 mov's and a shl).
- Use movzwl + leal instead of movl + movw + shll + addl.
- Use 'xchgl %eax,%foo' rather than 'movl %eax,%foo' for cases where
it's ok to trash %eax. xchgl %eax, foo is a 1-byte opcode whereas the
mov is a 2-byte opcode.
- Use movzwl rather than xorl + movw.
MFC after: 1 week
rather than just emulating mov cr0, eax. This fixes some Compaq/HP BIOS
with DMA (as the BIOS tried to read cr3 so it could translate addresses
if paging was enabled).
MFC after: 1 week
- Make the PROBE_KEYBOARD option better resemble the -P option in
boot2, i.e., if keyboard isn't present then boot with both
RB_SERIAL and RB_MULTIPLE set.
Reviewed by: jhb
fixes filesystem corruption when nextboot.conf is located after
cylinder 1023. The bug appears to have been introduced at the time
bd_read was copied to create bd_write.
PR: bin/98005
Reported by: yar
MFC after: 1 week
selection and not always beeping on startup. The two bytes for the extra
'jmp' instruction were obtained by removing recognition of BSD/OS
partitions.
Requested by: many
Tested by: subset of many
Head nod: imp, keramida
MFC after: 2 weeks
Otherwise, we could match on a filename that had the wrong last character
(such as /boot/loaded instead of /boot/loader).
PR: kern/95625
Submitted by: Oliver Fromme <olli@secnetix.de>
MFC after: 1 month
controller to get ready (65K x ISA access time, visually around 1 second).
If we have wait more than that amount it's likely that the hardware is a
legacy-free one and simply doesn't have keyboard controller and doesn't
require enabling A20 at all.
This makes cdboot working for MacBook Pro with Boot Camp.
MFC after: 1 day
Use 'BOOT_SENSITIVE_INFO=YES' variable to turn them on.
- Use 'uint*_t' instead of 'u_int*_t', correct compilation warnings, and
update copyright while I am here.
3MB of physical memory for heap instead of range between 1MB and 4MB.
This makes this feature working with PAE and amd64 kernels, which are
loaded at 2MB. Teach i386_copyin() to avoid using range allocated by
heap in such case, so that it won't trash heap in the low memory
conditions.
This should make loading bzip2-compressed kernels/modules/mfs images
generally useable, so that re@ team is welcome to evaluate merits
of using this feature in the installation CDs.
Valuable suggestions by: jhb
provide enough room for decompression (up to 2.5MB is necessary). This
should be safe to do since we load i386 kernels after 8MB mark now, so
that 16MB is the minimum amount of RAM necessary to even boot FreeBSD.
This makes bzip2-support practically useable.
memory directly available to loader(8) and friends was limited to 640K on i386.
Those times have passed long time ago and now loader(8) can directly access
up to 4GB of RAM at least theoretically. At the same time, there are several
places where it's assumed that malloc() will only allocate memory within
first megabyte.
Remove that assumption by allocating appropriate bounce buffers for BIOS
calls on stack where necessary.
This allows using memory above first megabyte for heap if necessary.
the serial console speed (i386 and amd64 only). If the previous
stage boot loader requested a serial console (RB_SERIAL or RB_MULTIPLE)
then the default speed is determined from the current serial port
speed. Otherwise it is set to 9600 or the value of BOOT_COMCONSOLE_SPEED
at compile time.
This makes it possible to set the serial port speed once in
/boot.config and the setting will propagate to boot2, loader and
the kernel serial console.
/boot.config or on the "boot:" prompt line via a "-S<speed>" flag,
e.g. "-h -S19200". This adds about 50 bytes to the size of boot2
and required a few other small changes to limit the size impact.
This changes only affects boot2; there are further loader changes
to follow.
variables to loader:
hint.smbios.0.enabled "YES" when SMBIOS is detected
hint.smbios.0.bios.vendor BIOS vendor
hint.smbios.0.bios.version BIOS version
hint.smbios.0.bios.reldate BIOS release date
hint.smbios.0.system.maker System manufacturer
hint.smbios.0.system.product System product name
hint.smbios.0.system.version System version number
hint.smbios.0.planar.maker Base board manufacturer
hint.smbios.0.planar.product Base board product name
hint.smbios.0.planar.version Base board version number
hint.smbios.0.chassis.maker Enclosure manufacturer
hint.smbios.0.chassis.version Enclosure version
These strings can be used to detect hardware quirks and to set appropriate
flags. For example, Compaq R3000 series and some HP laptops require
hint.atkbd.0.flags="0x9"
to boot. See amd64/67745 for more detail.
Note: Please do not abuse this feature to resolve general problem when it
can be fixed programmatically. This must be used as a last resort.
PR: kern/81449
Approved by: anholt (mentor)
- Teach the i386 and pc98 loaders to honor multiple console requests from
their respective boot2 binaries so that the same console(s) are used in
both boot2 and the loader.
- Since the kernel doesn't support multiple consoles, whichever console is
listed first is treated as the "primary" console and is passed to the
kernel in the boot_howto flags.
PR: kern/66425
Submitted by: Gavin Atkinson gavin at ury dot york dot ac dot uk
MFC after: 1 week
I think all we really need is -fno-sse2.
I really don't like cluttering up the compiler invocation,
but this bigger hammer will fix reported problems for now.
to stll be able to mount NFS root as prescribed by DCHP configuration. Since
pxeboot is using TFTP to get to the files, pxeboot can not rely on NFS to
provide it a root directory hande as a side effect. pxeboot has to make RPC
mount call itself.
and assume that the BIOS has set it up for us. This allows folks with a
serial-aware BIOS to set the BIOS to speeds above 9600 and allow boot0 to
just use the existing settings.
- Purge some gratuitous cpp comments as per style(9).
Submitted by: Danny Braniss danny at cs dot huji dot ac dot il (1)
MFC after: 1 month
assembler to cpp(1) comment conversions. This allows btx to compile again
when BTX_SERIAL is defined.
Reported by: Danny Braniss danny at cs dot huji dot ac dot il
MFC after: 1 month
to 4.0 and RELENG_3), the BTX mini-kernel used paging rather than flat
mode and clients were limited to a virtual address space of 16 megabytes.
Because of this limitation, boot2 silently masked all physical addresses
in any binaries it loaded so that they were always loaded into the first
16 Meg. Since BTX no longer has this limitation (and hasn't for a long
time), remove the masking from boot2. This allows boot2 to load kernels
larger than about 12 to 14 meg (12 for non-PAE, 14 for PAE).
Submitted by: Sergey Lyubka devnull at uptsoft dot com
MFC after: 1 month
format modules, which are currently only used on the amd64 platform.
This initial implementation just parses enough of the module to
allow it to extract dependencies and load all the bits into the
right place in memory, so the kernel must still do the full relocation
and linking. The details of the loaded sections are passed to the
kernel by supplying a copy of the ELF section header table as module
metadata with the MODINFOMD_SHDR tag.
This way of operation is more robust than the "AI" used
before.
Add flags to mbr accessible from make.conf as BOOT_MBR_FLAGS.
Only one flag is defined now, "allow using packet mode", which
is 0x80 in accord with the rest of i386 boot code. The "packet"
flag is on by default.
PR: i386/70241
Submitted by: Valentin Nechayev <netch <@> netch.kiev.ua> (inital version)
Discussed with: jhb (by Valentin Nechayev)
Tested on: bochs (with EDD turned on or off by patching the BIOS), PCs
the flag, fall back to the old INT13/AH=02 function if that fails.
This way of operation is less likely to fail with modern BIOSes and
large disks of strange geometries.
PR: i386/70241
Submitted by: Valentin Nechayev <netch <@> netch.kiev.ua> (inital version)
Discussed with: jhb (by Valentin Nechayev)
Tested on: bochs (with EDD turned on or off by patching the BIOS), PCs
have clear idea on boot2 BSS size and leaves portion of it not zeroed out.
btxcsu.s is in much better position for this job.
Obtained from: DragonflyBSD (with minor adjustments)
