Re: [Qemu-devel] Re: [PATCH 4/4] ppc4xx: load Bamboo kernel, initrd, and fdt at fixed addresses

[Edgar E. Iglesias]

On Fri, Aug 06, 2010 at 10:55:36AM -0700, Hollis Blanchard wrote:
> On Thu, Aug 5, 2010 at 7:39 PM, Liu Yu-B13201 <address@hidden> wrote:
> >
> >
> >> -----Original Message-----
> >> From: address@hidden
> >> [mailto:address@hidden On Behalf Of Hollis Blanchard
> >> Sent: Thursday, August 05, 2010 8:22 AM
> >> To: address@hidden
> >> Cc: address@hidden
> >> Subject: [PATCH 4/4] ppc4xx: load Bamboo kernel, initrd, and
> >> fdt at fixed addresses
> >>
> >> We can't use the return value of load_uimage() for the kernel
> >> because it
> >> can't account for BSS size, and the PowerPC kernel does not relocate
> >> blobs before zeroing BSS.
> >>
> >> Instead, we now load at the fixed addresses chosen by u-boot
> >> (the normal
> >> firmware for the board).
> >>
> >
> > What will us do if the uImage become bigger and fixed size is not
> > enough?
> 
> That was my question to Edgar, which was not answered. In u-boot, one
> would change some environment variables. With this code in qemu, the
> only recourse would be to edit ppc440_bamboo.c and rebuild.

My objection to the first patch was mainly about putting ppc related
magics into the generic load_uimage call. If you want to do clever
things in the ppc bootloading code, that may be fine, but in IMO you
should try to mimic the uboot behaviour as much as possible when loading
uimages.

Cheers