Running with VGA

YhLu YhLu at
Fri Jan 14 17:23:01 CET 2005

I add the code to amd_earlymtrr.c but found two problem
1. in the cpu init, the second cpu cache can not be enabled. (still using
value set by amd_earlymtrr.c). ( before the amd_mtrr.c called by init).
2. some slow in auto.c stage. Maybe because of before enable cache for
LinuxBIOS rom flash, there is more instruction to enable fixed mtrrs.

So I prefer to two phase dev_init loop.

If you want me send the amd_earlymtrr.c with fixed mtrr enablement, please
let me know.


-----Original Message-----
From: Li-Ta Lo [mailto:ollie at] 
Sent: Friday, January 14, 2005 2:13 PM
To: YhLu
Cc: Sagiv Yefet; LinuxBIOS
Subject: RE: Running with VGA

On Fri, 2005-01-14 at 12:45, YhLu wrote:
> I check the amd_early_mtrr.c with old amd It seems the only
> difference is not enable SYSCFG_MSR_MtrrFixDramModEn before clear MTRR
> fixed.

Probably I didn't commit all the old code I used to have.
Anyway, the things we have to do in early_mtrr.c are:

	1. enable SYSCFG_MSR_MtrrFixDramModEn
	2. set fixed mtrrs for 0-0x9FFFF and 0xC0000-0xFFFFF
	3. set fixed mtrrs for 0xA0000-0xBFFF to UC
	4. disable SYSCFG_MSR_MtrrFixDramModEn
	5. enable SYSCFG_MSR_MtrrFixDramEn


> I enable that, but the result shows no change....
> YH

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