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<TITLE>RE: x86 memory detection</TITLE>
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<P><FONT SIZE=2>I think the call chain is like this<BR>
<BR>
main() (arch/x86/boot/main.c) calls detect_memory() (arch/x86/boot/memory.c) which calls detect_memory_xxxxx() functions, they invoke bios interrupts to determine the amount of RAM & fill the boot_params structure.<BR>
<BR>
<BR>
Sudheer<BR>
<BR>
<BR>
<BR>
-----Original Message-----<BR>
From: kernelnewbies-bounces@kernelnewbies.org on behalf of Arun S<BR>
Sent: Thu 2/3/2011 10:18 AM<BR>
To: kernelnewbies@kernelnewbies.org<BR>
Subject: x86 memory detection<BR>
<BR>
Hi,<BR>
How does the kernel detects the amount of available System RAM in the<BR>
system under x86 architecture?.<BR>
<BR>
Under 2.6.x kernels,<BR>
<BR>
<BR>
1. Does it use BIOS interrupt 15 for determining the RAM<BR>
<BR>
OR<BR>
<BR>
2. Does the boot loader fills the e820_map as explained<BR>
inDocumentation/x86/boot.txt & Documentation/x86/zero-page.txt and the<BR>
kernel uses in information<BR>
<BR>
OR<BR>
<BR>
3. Is there any other mechanism (if so, in which file under kernel tree I<BR>
can find this detection code)<BR>
<BR>
<BR>
<BR>
Thanks,<BR>
Arun<BR>
<BR>
</FONT>
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