Re: [LinuxBIOS] dual core disable?

[Lu, Yinghai]

Northbridge.c cpu_bus_scan need to be modified too, you need to assume
the CONFIG_LOGICAL_CPU==1 there..

YH

-----Original Message-----
From: [e-mail]
[mailto:[e-mail]] On Behalf Of Lu, Yinghai
Sent: Monday, November 07, 2005 3:55 PM
To: Greg Johnson
Cc: [e-mail]
Subject: Re: [LinuxBIOS] dual core disable?

OK,

We may need to set the nbcfg 54 bit even disable the dual core.

Please several lines
1. src/cpu/dualcore/dualcore.c 
//If(read_option(CMOS_VSTART_dual_core.....
2. in you cache_as_ram_auto.c
//#if CONFIG_LOGICAL_CPUS == 1
    Set_apicid_cpuid_lo();
//#endif

YH

-----Original Message-----
From: Greg Johnson [mailto:[e-mail]] 
Sent: Monday, November 07, 2005 3:37 PM
To: Lu, Yinghai
Cc: Ronald G Minnich; Greg Johnson; [e-mail]
Subject: Re: [LinuxBIOS] dual core disable?

On Mon, Nov 07, 2005 at 03:00:09PM -0800, Lu, Yinghai wrote:
> ?
>
> In Normal BIOS, is there option to disable dual core?

No.  I'm pretty sure that I'm really getting two cores on one socket.
Memory bandwidth is affected when running on both cores.  In any case,
Linux K8 NUMA is confused:

p5:~# numactl --show
policy: default
preferred node: current
cpubind: 0
membind: 0 1

Greg

[LinuxBIOS] dual core disable?

[Greg Johnson]

YH,

I'm not sure I'm quite following.  I tried making the changes you
suggested, but it still looks the same.  Linux still identifies it as a
single socket with two cores.  I've rechecked the performance and it
still looks like a single socket with two cores (measuring memory
latencies and bandwidth).  Any other ideas?

Thanks,

Greg

On Mon, Nov 07, 2005 at 04:33:08PM -0800, Lu, Yinghai wrote:
> Northbridge.c cpu_bus_scan need to be modified too, you need to assume
> the CONFIG_LOGICAL_CPU==1 there..
>
> YH
>
> -----Original Message-----
> From: [e-mail]
> [mailto:[e-mail]] On Behalf Of Lu, Yinghai
> Sent: Monday, November 07, 2005 3:55 PM
> To: Greg Johnson
> Cc: [e-mail]
> Subject: Re: [LinuxBIOS] dual core disable?
>
> OK,
>
> We may need to set the nbcfg 54 bit even disable the dual core.
>
> Please several lines
> src/cpu/dualcore/dualcore.c
>
> //If(read_option(CMOS_VSTART_dual_core.....
> 2. in you cache_as_ram_auto.c
> //#if CONFIG_LOGICAL_CPUS == 1
>    Set_apicid_cpuid_lo();
> //#endif
>
> YH