[okl4-developer] Boot L4Linux from vga

[zhiyi huang]

Hi Hal,
I have followed your following instructions, and I did boot L4Linux  
from console I/O. Thanks:)

However, I have got the following bug message while booting the kernel:
"Kernel BUG at include2/asm/dma-mapping.h: 98"

I did notice your reminder of "Be aware that none of the drivers  
requiring dma are enabled in the release."

Could it be possible that there is still some drivers requiring dma  
that are enabled? How can I find them and disable them?

I got the error message after root file system is mounted read-only,  
by the way.

Thanks for your help!
Zhiyi


> On Thu, 2007-10-04 at 09:48 +0200, Harry Vennik wrote:
> > Op 4-okt-2007, om 8:59 heeft Hal Ashburner het volgende geschreven:
> >
>
> > I think he tries the same thing as I'm planning to do: run an OKL4
> > based system on a PC, using console I/O instead of serial port.
> > (Btw. I tried this already some time ago, and then I was told by
> > someone on this mailing list that support for that was being worked
> > on... Didn't it make it into the 1.5.2 release?)
>
> Hi Harry,
> You can certainly use the vga console driver in OKLinux on hardware.
> use the machine=ia32_pc99_vga target
> test it worked by running it on the simulator by hand
> ./qemu -hda build/images/c.img -serial stdio
> Which will launch an SDL window emulating the VGA screen while keeping
> your serial output in your terminal window.
> In particular check that the keyboard works, and that it is enabled in
> the l4linux_config_ia32_vga configuration file.
>
> If you mount the c.img file with something like
> $ mkdir mnt_tmp
> $ sudo mount -o loop,offset=32256 c.img tmp
>
> You can then copy the contents of  mnt_tmp onto a partition of your  
> test
> box. You will probably need to set up grub on your test box.
> I found the easiest way for me was to install debian sarge on a test
> box.
> move /lib/tls to /lib/tls.bak
> Install a grub supported ethernet card in the box (eepro100 works well
> for me)
> Compile grub with support for the card then install it.
> Install a tftp server on your development machine.
>
> Then configuring grub so it can load an image via tftp from your
> development machine is reasonably straightforward and will save you a
> lot of time.
>
> If you don't want to do all that, just installing grub and adding the
> relevant lines to the menu.lst to boot image.elf will work albeit  
> making
> rebooting more manual.
>
> Be aware that none of the drivers requiring dma are enabled in the
> release.
>
> I'd definitely try to get a crash and burn test box that has a serial
> port.
>
>
> Another option for vga output is to enable it in the L4 configuration.
> This hasn't been tested for a while and may have suffered a bit of
> bit-rot. Let me know if its a problem and I'll see if I can find  
> time to
> have a look at it.
>