[U-Boot] [RFC] arm926ejs: fix jump to RAM nand_boot

V, Aneesh
2010-11-03T12:20:30Z

Dear Albert, Wolfgang,

> -----Original Message-----
> From: Albert ARIBAUD [mailto:albert.aribaud at free.fr]
> Sent: Wednesday, November 03, 2010 5:38 PM
> To: V, Aneesh
> Cc: Wolfgang Denk; u-boot at lists.denx.de; hs at denx.de
> Subject: Re: [RFC] arm926ejs: fix jump to RAM nand_boot
>
> Le 03/11/2010 13:03, V, Aneesh a ?crit :
>
> > Just curious. Why don't we allocate memory for such needs below
> the
> > u-boot (lower address) like we do for malloc area and stack. This
> way
> > the location where u-boot is relocated will only depend on the
> SDRAM
> > size and size of u-boot itself, right?
>
> My guess is that the same memory will be allocated by the OS after
> u-boot, and allocating at the same location in both occasions allows
> for
> things like flicker-free boot splashes and such.
>
> And if you allocate this below u-boot, you end up with a split
> memory
> map with some allocated space in the middle of useable OS or user
> space.
>
> So we allocate that at top of RAM, and later on, Linux can use all
> the
> memory below as a single contiguous area.

I get it now.

But in any case, there are many boards that do not use these features
like ours. Skipping relocation, if the support is provided may be
useful for such boards.

Anyway, as I said earlier, we will come back with data on how much
time can be saved by skipping relocation.

Best regards,
Aneesh