[U-Boot] Adding new partition in uboot

[David Gibson]

On Sun, Mar 21, 2010 at 06:13:44PM -0400, Sagar Heroorkar wrote:
> Hi David,
> 
> I was exploring the ways to add partition into the blob dynamically.
> 
> I followd the following steps.
> 
> 1) say we have 5 partitions.  Flash size is 128mb
> 
> norflash at 0,0{
> 1----------
> 2------------------
> 3
> ----
>     5
>       partition at f80000 {
>                         label = "u_booot";
>                         reg = <0xf80000 0x60000>;
>                     };
> 
> 2) i am trying to add 6th partition dynamically in uboot.
> 
>    I used the the nodeoffset of norflash at 0,0 which is parent offset wher i
> want to create 6th partiton. I passed  this parent offset to
>         ret  =  fdt_add_subnode(blob,nodeoffset,
> "partition at 6800000");

You should check ret for errors (< 0) before continuing.

>         nodeoffset = ret;
>         ptr[0] = 0x6800000;
>         ptr[1] = 0x800000;

How is ptr declared?

>         offset = 0x6800000;
>         regs[0] += size_delta;

How is regs[0] initialized?

>         memcpy(regs, ptr, plen);

Where did plen come from?

>         ret = fdt_setprop(blob, nodeoffset, "reg", regs, plen);

You should check for errors here too.

> I am printing the the blob later. i see that node is created but the last
> partition ie u-boot @ f80000  is going away.
> 
> the blob size is 8000 byes which we built using the
> 
> dtc -S 8000 -R 7 -I dts -O dtb -o file.dtb file.dts
> 
> 
> Let me know if we need to increase size of the blob or something which i m
> missing.
> This is going to help  a lot if you can reply.

For this case where there's a flash partition that's sometimes there
and sometimes not, it might be simpler to put all the partitions,
including the not-always-present ones in the dts.  Then you can use
fdt_nop_subnode() to remove the extra one on systems where it's not
present.

-- 
David Gibson			| I'll have my music baroque, and my code
david AT gibson.dropbear.id.au	| minimalist, thank you.  NOT _the_ _other_
				| _way_ _around_!
http://www.ozlabs.org/~dgibson