* MPS table vs ACPI
@ 2011-06-29 22:32 sreenivasa reddy berahalli
2011-06-30 0:40 ` Yinghai
0 siblings, 1 reply; 2+ messages in thread
From: sreenivasa reddy berahalli @ 2011-06-29 22:32 UTC (permalink / raw)
To: tglx, mingo, hpa, x86, yinghai, Feng Tang, ebiederm, linux-kernel
Hello All,
Recent interaction with BIOS teams within in my Organization left me
wondering if MP table spec from Intel is no more a mandatory one
http://www.intel.com/design/pentium/datashts/24201606.pdf
Section #8.4.5 http://www.intel.com/Assets/PDF/manual/253668.pdf
Talks as ACPI or MPS table.
That means BIOS can report through ACPI tables only.
I looked through x86 boot sequence and notice Linux scanning for MPS
table in below locations and Linux doesn't seem to go further without
MPS table or doesn't know how to live with ACPI only.
1) Scan the bottom 1K for a signature
2) Scan the top 1K of base RAM
3) Scan the 64K of bios
Your insights into this topic are appreciated.
Thanks,
Sreenivas
^ permalink raw reply [flat|nested] 2+ messages in thread
* Re: MPS table vs ACPI
2011-06-29 22:32 MPS table vs ACPI sreenivasa reddy berahalli
@ 2011-06-30 0:40 ` Yinghai
0 siblings, 0 replies; 2+ messages in thread
From: Yinghai @ 2011-06-30 0:40 UTC (permalink / raw)
To: sreenivasa reddy berahalli
Cc: tglx, mingo, hpa, x86, Feng Tang, ebiederm, linux-kernel
On Jun 29, 2011, at 3:32 PM, sreenivasa reddy berahalli <sreenivasa-reddy-berahalli@hp.com> wrote:
> Hello All,
>
> Recent interaction with BIOS teams within in my Organization left me
> wondering if MP table spec from Intel is no more a mandatory one
> http://www.intel.com/design/pentium/datashts/24201606.pdf
>
> Section #8.4.5 http://www.intel.com/Assets/PDF/manual/253668.pdf
> Talks as ACPI or MPS table.
> That means BIOS can report through ACPI tables only.
>
> I looked through x86 boot sequence and notice Linux scanning for MPS
> table in below locations and Linux doesn't seem to go further without
> MPS table or doesn't know how to live with ACPI only.
> 1) Scan the bottom 1K for a signature
> 2) Scan the top 1K of base RAM
> 3) Scan the 64K of bios
Have one system with x2apic pre-enabled in bios, and it does not have mps table from bios. At least 2.6.32 based distribution kernel works well.
Current kernel works well too if you have acpi enabled in kernel.
Mptable assume apicid is 8 bits
Thanks
Yinghai
^ permalink raw reply [flat|nested] 2+ messages in thread
end of thread, other threads:[~2011-06-30 0:43 UTC | newest]
Thread overview: 2+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2011-06-29 22:32 MPS table vs ACPI sreenivasa reddy berahalli
2011-06-30 0:40 ` Yinghai
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.