Date: Thu, 06 Nov 1997 03:30:53 -0600 From: Tony Overfield <tony@dell.com> To: Nate Williams <nate@mt.sri.com>, Terry Lambert <tlambert@primenet.com> Cc: jamil@trojanhorse.ml.org, hackers@freebsd.org Subject: Re: >64MB Message-ID: <3.0.3.32.19971106033053.006ede20@bugs.us.dell.com> In-Reply-To: <199711052046.NAA20675@rocky.mt.sri.com> References: <199711051858.LAA14121@usr02.primenet.com> <3.0.3.32.19971105020626.006da974@bugs.us.dell.com> <199711051858.LAA14121@usr02.primenet.com>
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Tony Overfield writes:
>> > The bootloader already makes the "64 MB limited" BIOS call and sends
>> > this value to the kernel, but for some strange reason, the kernel
>> > tosses that value away in favor of the sometimes bogus CMOS value.
>> > Using this BIOS call's result instead of tossing it would resolve
>> > my complaint about the CMOS groping.
At 01:46 PM 11/5/97 -0700, Nate Williams wrote:
>Uhh, no. From i386/i386/machdep.c:
>
> /*
> * Warn if the official BIOS interface disagrees with the RTC
> * interface used above about the amount of base memory or the
> * amount of extended memory. Prefer the BIOS value for the base
> * memory.....
>
>So, we're definitely preferring the BIOS's value for the case of
>extended memory.
Sorry, but that's incorrect.
If you read the source code and look for bootinfo.bi_extmem, you'll see
that it is only used to produce a warning message.
In your citation, you inexplicably removed the tail end of the comment
which includes, among other things, this text:
* ... Prefer the RTC value for extended memory.
* Eventually the hackish interface shouldn't even be looked at.
*/
So the comment and the source code both agree that the BIOS value for
extended memory is overwritten by the value pulled from CMOS, the
BIOS value is not prefered, which matches my original complaint.
-
Tony
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