[LinuxBIOS] MB1030 / 3036 VGA comes up :D

Christian Sühs chris at suehsi.de
Tue May 2 19:43:29 CEST 2006

> I think we are ok.  There is no SMM in the whole system.  The GX1
> actually has real PCI config space registers.  And since he has an
> external VGA VSA isn't necessary to do any of the VGA stuff.  But
> Steve's previous mail on _completely_ disabling the internal VGA of
> the cs5530 also mentioned that for an external setup some SMM trap
> needs to be disabled.

Can you have a second look to the cpu_setup section under 

I have read this again and again, but for me it seems there are some 
false writings to the registers.

However, the datasheet says, that the SMM bit can only be set, if CCR3 
is 0 or the CPU is in SMI mode.

If I'm right, this bit is not correct set, doesn't matter default is 00 
and so there should be no SMM.

Later CCR3 is set to 0x14 in that case there is a try to set a reserved 
bit. I'm not sure what happens in those case.

Also there is a third write to CCR3 0xf8 for that write the SUSP_SSM_EN 
bit is set to 1 whatever this means ;)

Datasheet page 50 - 56

>>>So its crashing 'inside' of a printk.  0x3cf is a VGA index register.
>>Well, I think so. Many logs looks like the one above. The first
>>character is printed. Than nothing no more.
> Man, this just smells like some sort of interrupt problem.  Can we
> have printk do a cli() and  disable all interrupts when it runs?

I hope somebody has the answer.

> --
> Richard A. Smith

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