RE: mtrr

[YhLu]

x86_setup_mtrrs should be split to

x86_setup_fixed_mtrrs
x86_setup_var_mtrrs
x86_setup_enable_mtrrs

and for Opteron it can reuse 
x86_setup_var_mtrrs
x86_setup_enable_mtrrs

and 
x86_setup_var_mtrrs can take the cupid or sth as parameter to find out 40bit
or 32 bit.

YH

-----Original Message-----
From: [e-mail] [mailto:[e-mail]] 
Sent: Thursday, November 11, 2004 6:20 PM
To: YhLu
Cc: 'Ronald G. Minnich'; '[e-mail]'
Subject: Re: mtrr

YhLu  writes:
> In the cpu/x86/mtrr/mtrr.c
>
> #warning "FIXME I do not properly handle address more than 36 physical
> address bits"
> #ifdef k8
> # define ADDRESS_BITS 40
> #else
> # define ADDRESS_BITS 36
> #endif
> #define ADDRESS_BITS_HIGH (ADDRESS_BITS - 32)
> #define ADDRESS_MASK_HIGH ((1u << ADDRESS_BITS_HIGH) - 1)
>
> It seems someone already remove k8 from Option.lb
>
> Then ....
>
> Regards

Interesting.  The mtrr's actually work and the kernel is confused.

However what we need to do is call the appropriate cpuid function
to compute it or pass in the number of address bits.  It should not be
a compile time option, at least not in the generic code.  What
happens when we get can plug in cpus with different address bit
limits.

Eric