Messages in this thread |  | | | From | Bodo Eggert <> | | Subject | Re: how to tell linux (on x86) to ignore 1M or memory | | Date | Fri, 20 Apr 2007 23:39:54 +0200 |
| |
Rene Herman <rene.herman@gmail.com> wrote: > On 04/19/2007 04:18 PM, Bart Trojanowski wrote:
>> I need to preserve some state from the bios before entering protected >> mode. For now I want to copy it into some ram accessible by real-mode, >> say the last megabyte visible in real-mode. >> >> What's the easiest way to have linux ignore the megabyte starting at 15M? > > Note that real-mode can only access the first megabyte (*) and not the first > 16. 16MB is the 16-bit protected mode (286) limit. > > (*) well, the first 1M + 64K - 16 bytes using segment FFFF assuming A20 is > enabled and x > 1 in x86...
Interrupt 15h, function 87h allows copying from/to extended memory. You might like to look into Ralph Brown's interrupt list for more details.
You could also cpio-gzip the data and append it to the initramfs. -- Fun things to slip into your budget Does that line item say 'Personal Massage System' Oops, it's supposed to be 'Message'. Go ahead and sign the authorization, Boss; I'll correct it later. (Iike Hell I will) - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
|  |