[coyotos-dev] SMP Terminology (was: Re[2]: Coyotos SMP?)

[Valerio Bellizzomi]

On 25/10/2007, at 7.52, Jonathan S. Shapiro wrote:

>On Thu, 2007-10-25 at 02:03 +0200, Valerio Bellizzomi wrote:
>> Hi,
>> 
>> What is the exact meaning of BSP and AP ?
>
>
>BSP  == Board Support Package.  On embedded systems, you typically have
>many boards which may have different low level hardware. In particular,
>the memory controller may differ from one board to the next.
>
>For these environments, you don't tend to build a kernel to fit an
>architecture. You build it to fit a particular board.
>
>
>BSP == Bootstrap Processor. This is the processor that is elected
>shortly after power-on to run the BIOS.  This processor becomes CPU0 in
>Coyotos (and most other OS's). It is therefore the one that initializes
>the operating system.
>
>AP = application processor.  This is Intel-speak. Any processor that did
>not win the BSP election is an AP. These are the second and subsequent
>processors.
>
>
>I will generally use the term "cpu0" when I mean the bootstrap
>processor. When I use the term BSP, I'll be referring to the board
>support package.
>
>
>Have a look at section 7.5.1 of the IA-32 Software Developer's Manual,
>Vol 3.

Thank you, I have looked  at it.
That section, does not specify how the boot-strap processor is elected. I
guess that if CPU0 fails it is elected in sequential order.
If CPU0 fails, it cannot be an AP either, and so forth.
Hmm.

>
>
>shap