[PATCH] Support multiple MEM tags with atags->fdt conversion
Nicolas Pitre
nicolas.pitre at linaro.org
Wed Jun 15 16:20:15 EDT 2011
On Wed, 15 Jun 2011, David Brown wrote:
> On Wed, Jun 15 2011, Nicolas Pitre wrote:
>
> > On Tue, 14 Jun 2011, David Brown wrote:
> >
> >> Some targets have multiple memory regions. Parse up to 8 of these
> >> when converting the atags to fdt.
> >>
> >> Signed-off-by: David Brown <davidb at codeaurora.org>
> >
> > I've added your patch to my zImage patch queue.
> >
> >> With this change, I am able to boot MSM8x60 combining ATAGS and my DT.
> >> It seems to work as long as my device tree has placeholders for all of
> >> the properties I need.
> >
> > I think those missing nodes should simply be created if missing. I
> > however don't see any function in the libfdt API to do that -- there is
> > fdt_add_subnode() but no fdt_add_node(). Any DT expert please?
>
> It does seem to only work if I already have nodes that are large enough
> to hold the properties coming from the ATAG. For example, I have to
> have an array of memory reg values large enough, as well as a command
> line large enough to hold the one passed from the bootloader.
>
> If the DTB's command line is smaller than the one from ATAG, it just
> silently leaves the DTB one in place.
That I can explain, and that looks easy to fix.
Nicolas
More information about the linux-arm-kernel
mailing list