Date: Mon, 5 Oct 1998 14:04:50 +0200 (SAT) From: Robert Nordier <rnordier@nordier.com> To: eivind@yes.no (Eivind Eklund) Cc: rnordier@FreeBSD.ORG, cvs-committers@FreeBSD.ORG, cvs-all@FreeBSD.ORG Subject: Re: cvs commit: src/sys/boot/i386/boot0 - Imported sources Message-ID: <199810051204.OAA10923@ceia.nordier.com> In-Reply-To: <19981005131152.55016@follo.net> from Eivind Eklund at "Oct 5, 98 01:11:52 pm"
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Eivind Eklund wrote:
> On Mon, Oct 05, 1998 at 03:08:37AM -0700, Robert Nordier wrote:
> > rnordier 1998/10/05 03:08:37 PDT
> >
> > src/sys/boot/i386/boot0 - Imported sources
> > Update of /home/ncvs/src/sys/boot/i386/boot0
> > In directory freefall.freebsd.org:/d/users/rnordier/boot0
> >
> > Log Message:
> > boot0 is a booteasy (boot manager) workalike with EDD support.
> ^^^
> The closest I get is 'Educational Doctorate' (similar to PhD), but I
> assume this is not the intended meaning :-)
> Do you care to illuminate?
:-)
Used for "Enhanced Disk Drive" support in the PC BIOS world. These are
sometimes also called the IBM/MS INT 13 Extensions.
They enable a PC BIOS to support IDE drives exceeding 528 MB (nominal:
actually 1024 * 16 * 63 * 512 bytes).
The conventional PC BIOS supports disk access only up to cylinder 1023.
EDD uses a packet structure which contains a 64-bit LBA address, rather
than cylinder, head, sector values.
The idea is to free FreeBSD from the current restriction that the
FreeBSD slice on i386 must begin far enough below cylinder 1023 that
the kernel can be loaded using conventional BIOS services.
http://www.phoenix.com/products/specs-edd11.pdf
--
Robert Nordier
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