[PATCH 1/2] ARM: Add Kconfig option to use mkimage -T kernel_noload

[Uwe Kleine-König]

On Wed, Feb 29, 2012 at 10:33:58AM -0800, Tim Bird wrote:
> On 02/29/2012 10:14 AM, Jean-Christophe PLAGNIOL-VILLARD wrote:
> > On 08:58 Wed 29 Feb     , Stephen Warren wrote:
> >> Jean-Christophe PLAGNIOL-VILLARD wrote at Wednesday, February 29, 2012 5:30 AM:
> >>> On 17:03 Tue 28 Feb     , Stephen Warren wrote:
> >>>> uImage files typically encode a single absolute load and entry address.
> >>>> This is inconvenient when attempting to share that uImage across multiple
> >>>> SoCs with different physical RAM addresses. Recent versions of mkimage
> >>>> implement a "kernel_noload" image type which encodes no absolute load
> >>>> address, and a relative entry address. This works well for uImage-wrapped
> >>>> ARM zImages, since they are relocatable.
> >>>>
> >>>> This is enabled by commit b9b50e89d317c58becd0e2d7fac2e21e3a81dd0a
> >>>> "image: Implement IH_TYPE_KERNEL_NOLOAD" in U-Boot.
> >>>>
> >>>> Signed-off-by: Stephen Warren <swarren at nvidia.com>
> >>>> ---
> >>>> I assume I should put this into the ARM patch tracker if it's OK?
> >>>
> >>> Again a new option for uImage no why not just boot the zImage
> >>>
> >>> in this case the uImage is useless
> >>
> >> U-Boot doesn't support zImage at present.
> >>
> >> A patch was posted to support it at least for ARM, but needed a little
> >> work before it could be committed.
> > Sorry I see no advantage to have the uImage build by the kernel anymore as
> > we have a relocatable zImage
> > 
> > I'll even drop its support
> 
> This seems at least premature, and possibly ill-advised in general.
> There are lots of U-Boot images out in the field, many of which that
> are rarely updated. A lot of workflow will be disrupted unnecessarily
> by a change like this.
> 
> Could you wait to drop uImage build support in the kernel until
> U-Boot supports zImage, and has worked it's way into the field
> for a few years?
I admit I didn't check for a few years, but regarding that the values
used to build the uImage from a zImage are (or at least were) quite bad,
I'd say deprecate the uImage target today.

Uwe

-- 
Pengutronix e.K.                           | Uwe Kleine-König            |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |