[LinuxBIOS] MB1030 / 3036 I like 13 :D

Christian Sühs chris at suehsi.de
Thu Apr 27 10:57:34 CEST 2006

> But that may be a lot of extra overhead I know some of the romcc
> setups are alreday tight on rom space.
> To test you can just change line 36 in GX setup to be:
>         .long   BC_XMAP_2, 0xb0000000

That doesn't work, after that I changed also the line 57 in 
model_gx1_init.c to the same value with no success.

Than I thinked about the value.

BC_XMAP_2 = 00000000h is default.

This word described the read/write/cache/pci access for 8 adress ranges.
for each range we have to set 4 bits. If I want to enable read write for 
all 8 ranges I should set bit 1 & 2 to high.

--> first range  0011
--> second range 0011
and so on

= 00110011001100110011001100110011

this should be 0x33333333

I have insert this to the both files and it works ;)

(but at the moment I'm not sure)

ok, what happens.

The LB debug spokes out the vga.bios on 0xc0000, now (for now I have not 
verified, if this is the whole vga.bios)
and the emu is running much longer as before in printed debug lines.
Later the emu stops with no error and the system seems to hang, but we 
should now on the right way.

A few questions.

0xc0000 - 0xfffff is normaly Cached?
Means, should I set the cache bit?

How is the range 640k-1MB normally set in other systems.

If I right above, BC_XMAP_1 is set to 0x60 I think that is not very much 
for a system. think about my other problems later.

I would like to set the magic bit for vga to 00 (at the moment it is set 
for 4K I/O range and all vga instructions are enabled)



> Seems to me we've had this discussion before but I never remember the result. :(
> --
> Richard A. Smith

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