Re: For comment: draft BIOS use document for the kernel

Timur Tabi
2001-06-22T16:32:42Z

** Reply to message from Alan Cox <alan@lxorguk.ukuu.org.uk> on Fri, 22 Jun
2001 17:20:33 +0100 (BST)

> Firstly a call is made to BIOS INT 15 AX=0xE820 in order to read the
> E820 map. A maximum of 32 blocks are supported by current kernels. The
> 'SMAP' signature is required and tested. In addition the SMAP signature
> is restored each call, although not required by the specification in order
> to handle some know BIOS bugs.

FYI, in OS/2, the E820 call is made only on machines with a Pentium Pro or
higher, because apparently (and this is my guess) there are some motherboards
out there with older CPUs that don't return a reliable result to the E820 call.

--
Timur Tabi - ttabi@interactivesi.com
Interactive Silicon - http://www.interactivesi.com