On Wed, 31 Aug 2005, Martin Wilck wrote: > We are wondering why these masks are there in the subarch code at all. After > all, whether or not 8-bit APIC IDs are supported depends mainly on the CPU > type used. Why wouldn't it possible to have a "default" architecture with APIC > IDs > 15, if the CPUs allow it?
It actually depends on the APIC type, rather than the CPU. E.g. with Pentium systems the width of the ID is either 4 bits or 8 bits, depending on whether the integrated or an external 82489DX APIC is used. This should be able to be determined by the APIC version; for v <= 0xf the ID is 8-bit and for v >= 0x10 it used to be 4-bit. Now you only need to determine what is the value of v above 0x10 that makes the ID 8-bit again. Maciej - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
