[src/trunk]: src/sys/arch/x68k/stand Add a document about this directory.

[isaki <isaki%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/baffed29646b
branches:  trunk
changeset: 968480:baffed29646b
user:      isaki <isaki%NetBSD.org@localhost>
date:      Sat Jan 18 04:42:29 2020 +0000

description:
Add a document about this directory.
Reviewed by tsutsui@ on port-x68k.

diffstat:

 sys/arch/x68k/stand/README |  57 ++++++++++++++++++++++++++++++++++++++++++++++
 1 files changed, 57 insertions(+), 0 deletions(-)

diffs (61 lines):

diff -r cf7d999d0f62 -r baffed29646b sys/arch/x68k/stand/README
--- /dev/null   Thu Jan 01 00:00:00 1970 +0000
+++ b/sys/arch/x68k/stand/README        Sat Jan 18 04:42:29 2020 +0000
@@ -0,0 +1,57 @@
+$NetBSD: README,v 1.1 2020/01/18 04:42:29 isaki Exp $
+
+Primary bootloaders:
+       boot_ufs/
+               contains xxboot_ufs.
+               It is placed in ffs's boot area and loads secondary bootloader
+               from its filesystem (ffsv1/v2).
+               This historical primary bootloader uses custom ffs op functions
+               and can recognize Human68k partition table.
+               (See #ifdef SCSI_ADHOC_BOOTPART part for details)
+
+       boot_ustar/
+               is placed in floppy's sector#0 and loads secondary bootloader
+               from subsequent USTARFS.
+
+       xxboot/
+               contains following variants.
+               * cdboot_cd9660
+                       is placed in CD and loads secondary bootloader
+                       from cd9660 filesystem.
+               * xxboot_ffsv1
+               * xxboot_ffsv2
+               * xxboot_lfsv1
+               * xxboot_lfsv2
+                       is placed in each specified filesystem's boot area,
+                       and loads secondary bootloader from its filesystem.
+
+               These primary bootloaders use MI ffs/lfs op functions in
+               src/sys/lib/libsa. Currently these don't recognize Human68k
+               partition table.
+
+Secondary bootloaders:
+       boot/
+               boot is placed to / (root directory) and loads the kernel.
+
+       netboot/
+               netboot is the same as /boot except default boot device is
+               nfs using network interface and DHCP.
+               Currently only NE2000 based Neptune-X and Nereid are
+               supported.
+
+Other bootloaders:
+       mboot/
+               mboot is 0-th bootloader.
+               It is placed to sector#0 (as 1024byte/sector) of hard disk
+               as an alternative to genuine boot selector.  And loads
+               active partition's +0 sector (sector size depends media)
+               which should have primary bootloader.
+
+       loadbsd/
+               loadbsd.x is a Human68k executable and loads the kernel from
+               Human68k filesystem.
+
+Utility tools:
+       newdisk/
+               newdisk is a utility to create the "disk mark" for X680x0
+               SCSI IPL using mboot bootloader to make a disk bootable.