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Any sample asm code to load kernel from ISO 9660?

Posted: Thu Dec 26, 2013 11:34 am
by vinothkumar
Hi Everyone,
I have searched through the google and i'm not satisfied with that. I have only two reference for El torito bootloader that loads kernel
1.GRUB
2.ISOLINUX
but both two uses nasm and gcc to build a iso 9600 file system and loads kernel. Is there any simple asm bootloader to load kernel by searching through PVD using int 13h extended read?

Thanks,
Vinoth Kumar J

Re: Any sample asm code to load kernel from ISO 9660?

Posted: Thu Dec 26, 2013 6:12 pm
by Nable
Did you try searching before asking the question?
This may help: http://wiki.osdev.org/El-Torito#A_BareB ... tion_Table

Re: Any sample asm code to load kernel from ISO 9660?

Posted: Thu Dec 26, 2013 9:52 pm
by vinothkumar
Hi,
Thanks for the quick reply.
I know about that simple code. And my question is not that?. After that how to load kernel from that bootloader through int 13 extended read.

Thanks

Re: Any sample asm code to load kernel from ISO 9660?

Posted: Fri Dec 27, 2013 12:16 am
by nerdguy
I know about that simple code. And my question is not that?. After that how to load kernel from that bootloader through int 13 extended read.
INT 0x13, AH = 0x42 - Extended Read Sectors
Refer to this:
http://www.ctyme.com/intr/rb-0708.htm
The above link points to Ralf Brown's interrupt list, INT 0x13, AH = 0x42
You should first check whether the extensions are present or not,
Nice little doc:
http://pdos.csail.mit.edu/6.828/2012/re ... -cdrom.pdf
Also,
Since you said that you're not satisfied with ISOLINUX, However if you look at the ISOLINUX source carefully you should see this :
http://git.kernel.org/cgit/boot/syslinu ... olinux.asm (see after line 186)
but both two uses nasm and gcc to build a iso 9600
So what do you expect them to use?

Re: Any sample asm code to load kernel from ISO 9660?

Posted: Fri Dec 27, 2013 12:25 am
by vinothkumar
Hi,

Thanks for your fantastic reply.

I have reffered all those things. In ISOLINUX they have loaded the kernel and config file using pm_call load_config(which calls the fs.c and isolinux.c functions). They have build the filesystem driver through gcc.
So what do you expect them to use?
And i want a nasm code to build iso 9660 in own and loads simple kernel file into memory. Is there any sample means, it would be great helful for me.

Thanks,
Vinoth Kumar J