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

[Chris Gilbert <chris%netbsd.org@localhost>]

Module Name:    src
Committed By:   chris
Date:           Sun Feb  3 14:59:16 UTC 2008

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

Log Message:
Fix-up boot32 to work on A7000+

Logically the previous code should have worked but didn't.  It appeared to
fail when reading the relocation table from physical memory.

To work-around this issue we now compact the relocation table (it shrinks
from ~800 entries to ~15 on a 2.5MB kernel)  The compacted table is small
enough to copy into the page of memory we use to do the relocations.  The
relocation code can now find the table, and carry out the relocations.

To help with debugging the screen border will change colour:
Red:   Running without the MMU turned on (IE 1-1 physical mapping)
       Note that the border will stay red a while as we're copying the
       kernel over at this point.
Green: We've finished copying the kernel over (unless the code breaks
       this will be rarely seen)
Blue:  We're running on the bootstrap L1 table, and just about to call
       the kernel.

Other tweaks include:
* copy the kernel 32bits at a time, rather than 8 bits at a time.
* assert that the relocations are 32bit aligned (so the above works)
* flush the cache and write buffers before turning off the MMU.

Tested by myself on an A7000+.  Tested by skrll@ on Risc-PC and A7000.


To generate a diff of this commit:
cvs rdiff -r1.32 -r1.33 src/sys/arch/acorn32/stand/boot32/boot32.c
cvs rdiff -r1.2 -r1.3 src/sys/arch/acorn32/stand/boot32/start.S

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