CVS commit: src/sys/arch/acorn32/stand/boot32

[Reinoud Zandijk <reinoud%netbsd.org@localhost>]

Module Name:    src
Committed By:   reinoud
Date:           Mon Dec 30 15:54:47 UTC 2002

Modified Files:
        src/sys/arch/acorn32/stand/boot32: boot32.c

Log Message:
In the case there is just one SIMM and one memory bank from the SIMM things
got wrong when no VRAM was there.

Placing the video DRAM in front of the kernel is OK when its 1Mb since the
kernel wants to be on a Mb boundary. Placing the video DRAM in the last
SIMM bank at the front is also OK unless there is just one SIMM and just one
bank; then it got in the way again!

Solution is to put the DRAM at the end of the SIMM instead of the beginning!
This however can result in the non 16 kb alignment of the top of physical
RAM where the temporary L1 page tables are situated. If its not 16 kb aligned
then move the L1 page table address down and down until it is 16 kb aligned.
This memory will be reused later on anyway.

What to do when we really support changing screensizes... see it as a max?
or use a different sceme alltogether? It might not even be a bootloader
problem then allthough its memory is not showing up in the DRAM/VRAM
block counts wich needs to be fixed one day.


To generate a diff of this commit:
cvs rdiff -r1.5 -r1.6 src/sys/arch/acorn32/stand/boot32/boot32.c

Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.