Re: Build failure for ews4800mips

[Izumi Tsutsui <tsutsui%ceres.dti.ne.jp@localhost>]

> current build is broken for ews4800mips, in a way that puzzles me a bit.

IIRC this is the third time of the question.
I should have put proper descrtiption about the ugly hack...

> options         MEMORY_DISK_ROOT_SIZE=6144      # size of memory disk, in blocks (12)
> 
> Not sure what the (12) comment should mean, but this is 512 byte blocks, so
> available size for the image should be 3145728 bytes.

Well christos@ added that comment, but it should be (3M)?

> gunzip -c /others/hosts/ews4800mips/usr/mdec/boot_kernel.gz > boot-RAMDISK.tmp
> /usr/tools/bin/mipseb--netbsd-mdsetimage -v boot-RAMDISK.tmp netbsd-RAMDISK.gz
> mapped boot-RAMDISK.tmp
> got symbols from boot-RAMDISK.tmp
> root @ 0x15344/2129920
> mipseb--netbsd-mdsetimage: fs image (2130688 bytes) too big for buffer (2129920 bytes)

Short answer:

Bump this one:
https://nxr.netbsd.org/xref/src/sys/arch/ews4800mips/stand/boot/Makefile?r=1.23#41
>      41 BINKERNEL_SIZE	= '2 * 1024 * 1024 + 32 * 1024'

Quick description:

- The firmware of EWS4800 can load ECOFF binaries via network
- One easy way to load an installation kernel via netboot
  for bootstrap was to embed a ramdisk kernel into a bootloader
  (as bebox and prep did)
- I (ab)used mdsetimage(8) to embed a compressed ramdisk kernel into
  an ECOFF bootloader
   https://nxr.netbsd.org/xref/src/sys/arch/ews4800mips/stand/common/binkernel.c
   https://nxr.netbsd.org/xref/src/distrib/ews4800mips/floppies/instkernel/Makefile?r=1.8#20
- The kernel embeded as data is loaded via "datafs" (named "mem:" device)
  after bootloader starts
   https://nxr.netbsd.org/xref/src/sys/arch/ews4800mips/stand/common/datafs.c
- Once ramdisk grows enough, gzip(1) cannot compress the ramdisk kernel
  enough and its size exceeds space in the bootloader, defined as
  the above Makefile line

Note the installation bootloader of NetBSD/ews4800mips 8.0 just worked:
 https://dmesgd.nycbug.org/index.cgi?do=view&id=3717

---
Izumi Tsutsui