Peter Stuge wrote:
> Hi!
>
> We're developing a set-top-box using the National Semiconductors SC1200
> Internet Appliance System-On-Chip, which has some similarities with the
> SiS 630, but with even more stuff packed into it.
>
> For more information on the chip, visit http://www.national.com/ and do a
> search for the SC1200 but in short it's a GX1 CPU core and memory controller,
> a SuperIO-subsystem, PCI bridge, video processor, USB host, graphics
> controller and probably something else I've left out integrated into one BGA
> chip.
>
> We're currently looking into creating a minimal BIOS on our own, just enough
> to boot Linux in some way. But then I found the LinuxBIOS project and it
> seems like it would fit us very well. However, there is a slight problem
> with just putting together the needed code for the SC1200 "mainboard";
> proprietary object code is required to enable some of the functions of the
> chip. :\
What functions do you refer to? Why don't you ask NSC for the
Expressloader Source, it contains all the BIOS source in assembler.
We've been using it the past few months and are working on a version of
LinuxBIOS for the GX1 and SCx2xx.
> This object code is available from NSC and I have it, so I've
> gotten as far as building a BIOS of my own that will actually load Linux.
> But when Linux wants to mount root, the ramdisk isn't around in memory.
> I'm using Etherboot/32 to (down)load Linux but more flexibility would be
> very nice. Etherboot doesn't relocate the kernel, it places it at the right
> location in memory immediately, but the ramdisk is relocated. However, if I
> try to mount root over NFS instead of from memory I get oops:es, so I'm
> thinking that everything isn't quite right.
>
> The code from NSC only has graphics services, so I've implemented some of
> the services I found were used by Linux at boot, int 15/87,88,ee01,int 11,
> int 12 and a few more. I recently discovered that I've missed out on a few
> services that are used and I'm about to add them to my BIOS and try it out,
> but then I discovered LinuxBIOS and wanted to drop the people here a note.
>
> My immediate concern is to get Linux booting on the system, but, if
> practical, it would also be very nice to add SC1200 support to the LinuxBIOS
> project. I honestly think that would be of interest to NSC as well.
I offered NSC to get LinuxBIOS running on all of the NSC development
platforms months ago and they weren't interested.
Bari
