Linuxbios with Diskonchip?

[Devi Priya]

Hi,

I shall have my BIOS program, Linux kernel and filesystem in the same 
Diskonchip. I want to use linuxbios (for sc1200).  What is the physical 
memory mapping that should be done? SDRAM mapped to lower order address and 
Diskonchip to the higher order address. Is it correct?

_________________________________________________________________
Enjoy shopping online? Get this e credit card. 
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[gizara]

If I remember correctly, Disk-on-Chip comprises NAND flash technology which
inherently cannot execute in place, strictly sequential (data) accesses...
So you would still need some sort of rudimentary boot flash(NOR) or other
ROM to execute code to first load the BIOS, then the kernal, into shadow,
then main (DRAM) memory locations, respectively.

In a system I'm architecting we're still going to use a 256Kx8 flash for
LinuxBIOS, from there use JFFS2 and associated utilities to get the kernal
and various applications and data from a bare NAND on board.

This link and its links go into much more detail than I can in this email
about issues you may face:

http://www.linux-mtd.infradead.org/tech/nand.html

Good Luck!

----- Original Message -----
From: "Devi Priya" 
To: 
Sent: Wednesday, November 26, 2003 10:47 PM
Subject: Linuxbios with Diskonchip?
> Hi,
>
> I shall have my BIOS program, Linux kernel and filesystem in the same
> Diskonchip. I want to use linuxbios (for sc1200).  What is the physical
> memory mapping that should be done? SDRAM mapped to lower order address

and
> Diskonchip to the higher order address. Is it correct?
>
> Enjoy shopping online? Get this e credit card.
> http://server1.msn.co.in/features/amex/ It cuts cost & adds value!
>
> Linuxbios mailing list
> [e-mail]
> http://www.clustermatic.org/mailman/listinfo/linuxbios

[Niki Waibel]

the doc millennium "maps" the first 2 pages of the NAND flash into its high and low address space.
it _can_ be used to boot/init memory/copy nand pages to ram/jmp to ram.
but -- you have to do all that within 512 bytes of code.

mem layout of the doc millennium (2001) is:
address
0x0000 512bytes boot code (first 2 pages copied during power on via a reset mechanism)
       512bytes boot code (mirror)
       512bytes boot code (mirror)
       512bytes boot code (mirror)
0x0800 512bytes flash area window
       512bytes flash area window (mirror)
       512bytes flash area window (mirror)
       512bytes flash area window (mirror)
0x1000 512bytes control registers -- not all 512bytes used
       512bytes control registers -- not all 512bytes used (mirror)
       512bytes control registers -- not all 512bytes used (mirror)
       512bytes control registers -- not all 512bytes used (mirror)
0x1800 512bytes boot code (first 2 pages copied during power on via a reset mechanism)
       512bytes boot code (mirror)
       512bytes boot code (mirror)
       512bytes boot code (mirror)

i'd like to get this working on a via epia-m motherboard once.
replacing the existing bios.

niki

On 27-Nov-2003 gizara wrote:
> If I remember correctly, Disk-on-Chip comprises NAND flash technology which
> inherently cannot execute in place, strictly sequential (data) accesses...
> So you would still need some sort of rudimentary boot flash(NOR) or other
> ROM to execute code to first load the BIOS, then the kernal, into shadow,
> then main (DRAM) memory locations, respectively.
>
> In a system I'm architecting we're still going to use a 256Kx8 flash for
> LinuxBIOS, from there use JFFS2 and associated utilities to get the kernal
> and various applications and data from a bare NAND on board.
>
> This link and its links go into much more detail than I can in this email
> about issues you may face:
>
> http://www.linux-mtd.infradead.org/tech/nand.html
>
> Good Luck!
>
> ----- Original Message -----
> From: "Devi Priya" 
> To: 
> Sent: Wednesday, November 26, 2003 10:47 PM
> Subject: Linuxbios with Diskonchip?
> > Hi,
> >
> > I shall have my BIOS program, Linux kernel and filesystem in the same
> > Diskonchip. I want to use linuxbios (for sc1200).  What is the physical
> > memory mapping that should be done? SDRAM mapped to lower order address
>
> and
> > Diskonchip to the higher order address. Is it correct?
> >
> > Enjoy shopping online? Get this e credit card.
> > http://server1.msn.co.in/features/amex/ It cuts cost & adds value!
> >
> > Linuxbios mailing list
> > [e-mail]
> > http://www.clustermatic.org/mailman/listinfo/linuxbios
>
> Linuxbios mailing list
> [e-mail]
> http://www.clustermatic.org/mailman/listinfo/linuxbios

[ron minnich]

On Fri, 28 Nov 2003, Niki Waibel wrote:
> i'd like to get this working on a via epia-m motherboard once.
> replacing the existing bios.

good luck, it's a hard chipset to do startup in that little space.

ron

[ron minnich]

On Thu, 27 Nov 2003, gizara wrote:
> If I remember correctly, Disk-on-Chip comprises NAND flash technology which
> inherently cannot execute in place, strictly sequential (data) accesses...
> So you would still need some sort of rudimentary boot flash(NOR) or other
> ROM to execute code to first load the BIOS, then the kernal, into shadow,
> then main (DRAM) memory locations, respectively.

yes, and ollie lo did this three years ago on sis 630. see code, read 
HOWTO.

I am terse right now, can't type much due to stupid pinched nerve, so bear 
with me, but this was done and works fine. Ollie, can you fill in details?

ron