Copy stable/9 to releng/9.3 as part of the 9.3-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

MFC: r239063, r239064, r239069, r240852, r240854

- boot2: bunch of variables are turned into uint8_t.
- boot2: Remove unnecessary initializations.
- loader: replace ugly inb/outb re-implementations with cpufunc.h.
- Reduce diffs against i386.

MFC r235264: MFi386: improve argument passing via btxldr

MFC 226746:
Consolidate duplicate definitions of V86_CY() and V86_ZR() which check for
the carry and zero flags being set, respectively, in <btxv86.h> and use
them throughout the x86 boot code.

Copy head to stable/9 as part of 9.0-RELEASE release cycle.

Approved by: re (implicit)

Add 2 new archsw interfaces:
1. arch_loadaddr - used by platform code to adjust the address at which
the object gets loaded. Implement PC98 using this new interface instead
of using conditional compilation. For ELF objects the ELF header is
passed as the data pointer. For raw files it's the filename. Note that
ELF objects are first considered as raw files.
2. arch_loadseg - used by platform code to keep track of actual segments,
so that (instruction) caches can be flushed or translations can be
created. Both the ELF header as well as the program header are passed
to allow platform code to treat the kernel proper differently from any
additional modules and to have all the relevant details of the loaded
segment (e.g. protection).

Add setting machine type support to the loader.

MFC after: 2 week

MFi386: revision 200219

Improve the algorithm the loader uses to choose a memory range for its
heap when using a range above 1MB.

MFC after: 1 week

MFi386: revision 200216

Various small whitespace and style fixes.

Reduce diffs against i386.

- Initialize the vm86 structure to a known-good state. Specifically, always
set the %eflags used during a BIOS call via BTX to 0x202. Previously
the flags field was uninitialized garbage, and thus it was "random" if
interrupts were enabled or not during BIOS calls.
- Use constants from <machine/psl.h> for fields in %eflags.

MFC after: 3 days

MFi386: revision 1.41

Slightly cleanup the 'bootdev' concept on x86 by changing the various
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.

Extend struct devdesc with a unit field, called d_unit. Promote the
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.

Commit the results of the typo hunt by Darren Pilgrim.
This change affects documentation and comments only,
no real code involved.

PR: misc/101245
Submitted by: Darren Pilgrim <darren pilgrim bitfreak org>
Tested by: md5(1)
MFC after: 1 week

MFi386: revisions 1.34 and 1.36.

MFi386: revision 1.33.
> Cause all flags passed by boot2 to set the respective loader(8)
> boot_* variable. The end effect is that all flags from boot2
> are now passed to the kernel.

- Add support to the loader for multiple consoles.
- 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

Remove ifdef PC98.

MFi386: Set bi_basemem and bi_extmem variables.
Respect RB_MULTIPLE flag.

MFi386: revision 1.29.

Use __FBSDID().
Also some minor style cleanups.

MFi386: sys/boot/i386/loader/main.c revision 1.25

MFi386: sys/boot/i386/loader/main.c revision 1.24.

Merged from the following changes.

sys/boot/i386/btx/btx/Makefile 1.9
sys/boot/i386/btx/btx/btx.s 1.23
sys/boot/i386/libi386/biosdisk.c 1.32 and 1.33
sys/boot/i386/libi386/biosmem.c 1.5
sys/boot/i386/libi386/comconsole.c 1.8
sys/boot/i386/libi386/gatea20.c 1.3
sys/boot/i386/libi386/time.c 1.4
sys/boot/i386/libi386/vidconsole.c 1.13
sys/boot/i386/loader/Makefile 1.48
sys/boot/i386/loader/main.c 1.22

Merged from sys/boot/i386/loader/main.c revision 1.21.

Merged from sys/boot/i386/loader/main.c revision 1.23.

Sync with the following changes.

sys/boot/i386/libi386/Makefile 1.16 and 1.17
sys/boot/i386/loader/Makefile 1.44
sys/boot/i386/loader/main.c 1.20

Merged from sys/boot/i386/loader/main.c rev 1.19.

Synced with following files:
src/sys/boot/i386/Makefile.inc 1.1
src/sys/boot/i386/btx/btx/btx.s 1.15
src/sys/boot/i386/btx/btxldr/Makefile 1.8
src/sys/boot/i386/btx/btxldr/btxldr.s 1.9
src/sys/boot/i386/libi386/biosdisk.c 1.29
src/sys/boot/i386/loader/Makefile 1.42
src/sys/boot/i386/loader/main.c 1.18
(entry point address of loader was not changed.)

Reviewed by: nyan

Merge from the following changes.

sys/boot/i386/libi386/biosmem.c Rev 1.4
sys/boot/i386/libi386/time.c Rev 1.3
sys/boot/i386/loader/main.c Rev 1.16

- Supported the bd_getbigeom function and use this function to get BIOS
geometry.
- Use i386/libi386/bootinfo.c instead of pc98/libpc98/bootinfo.c.

Submitted by: IMAI Takeshi <take-i@ceres.dti.ne.jp>

Fixed warnings.

$Id$ -> $FreeBSD$

Use files under sys/boot/i386 instead of copying under sys/boot/pc98.

Submitted by: Takahashi Yoshihiro <nyan@dd.catv.ne.jp>

When SCSI IDs are not contiguous, the loader could not find correct
unit number for da device. This commit fixes this problem.

Submitted by: IMAI Takeshi <take-i@ceres.dti.ne.jp>

PC98 version of new boot loader. Because boot2 has not yet ported,
files in boot2 directory are copies from legacy biosboot.

Submitted by: IMAI Takeshi <take-i@ceres.dti.ne.jp>