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Altera_Forum's avatar
Altera_Forum
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21 years ago

About Microtronix Linux's boot procedure..

hello everyone:

I have questions about the boot procedure of Microtronix's Nios II linux distribution.

1. Is there a bootloader?If yes,how does it work?Is there any document available about this topic?

2.I want to create a root filesystem using just busybox,i followed the busybox section in the

reference guide,now i am confused about the Busybox's "init" application.

please tell me how to create proper "/etc/inittab" and "/etc/init.d/rcs" file for booting the

Microtronix's linux refernce design built from quick start guide.

Can i just copy the content of the original filesystem's "/etc/inittab" and "/etc/rc" to the busybox's 2 init files mentioned above respectively?

thanks

http://forum.niosforum.com/work2/style_emoticons/<#EMO_DIR#>/tongue.gif

5 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    21 years ago

    Hi trout,

    1. Microtronix&#39;s distribution has no bootloader, but someone have ported uboot to Nios II and posted it on this forum. You can have a search.

    2. An example inittab can be found in busybox/examples. And rcS is just an init script, I think you can copy the old rc file and have a try.
  • Altera_Forum's avatar
    Altera_Forum
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    21 years ago

    1. I think that there is a boot loader to load the kernel from flash into ram. It allows to execute the kernel code from ram. Also, the root file system is mounted into the ram...

    But I didn&#39;t find any information about boot loader.

    Christian
  • Altera_Forum's avatar
    Altera_Forum
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    21 years ago

    Hi Christian,

    Yes you are right, there is some bootstrap code to copy the kernel into ram from flash. I don&#39;t know if that is the kind of bootloader trout is thinking about. All it did is copying text and data into ram (as far as I know, root file system is not copied) and jump to the entry point...
  • Altera_Forum's avatar
    Altera_Forum
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    21 years ago

    Hello,

    I would like to have a confirmation about the root filesystem. The root filesystem is accessed from the flash or copied into the RAM? Where can I find the answer in the kernel source code (directory/source file).

    Best regards

    Christian
  • Altera_Forum's avatar
    Altera_Forum
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    21 years ago

    The romfs is accessed from flash. You can check this file:

    drivers/mtd/maps/microtronix.c

    You can also make the /dev/hda1 (compact flash) as the root filesystem. Still no files are copied to ram.

    If you are using ramdisk as the root filesystem, they are in ram.