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    SubjectRe: [PATCH 2/3] Kbuild: Implement CONFIG_UIMAGE_KERNEL_NOLOAD
    On Wed, 7 Mar 2012, Stephen Warren wrote:

    > On 03/07/2012 11:36 AM, Jean-Christophe PLAGNIOL-VILLARD wrote:
    > > On 11:40 Wed 07 Mar , Stephen Warren wrote:
    > >> On 03/07/2012 11:08 AM, Jean-Christophe PLAGNIOL-VILLARD wrote:
    > >>> On 17:30 Tue 06 Mar , Stephen Warren wrote:
    > >>>> This allows the user to use U-Boot's mkimage's -T kernel_noload option
    > >>>> if their arch Kconfig allows it, and they desire.
    > >>>>
    > >>>> Signed-off-by: Stephen Warren <>
    > >>>> ---
    > >>>> The next patch enables this new CONFIG_ALLOW_ option for ARM. I assume
    > >>>> that some other architectures will also be able to enable it, but I'm
    > >>>> not familiar enough with any to know which.
    > >>> I'm going to repeat. I don't think any impromevent here.
    > >>>
    > >>> with no specific kernel load address the uImage for is useless/
    > >>
    > >> No, the whole point of this type of kernel image is that it doesn't need
    > >> a specific load address; the kernel zImage can run from anywhere in RAM
    > >> (provided AUTO_ZRELADDR is enabled, subject to some slight
    > >> restrictions), and hence the uImage doesn't need to be loaded to or
    > >> moved to any particular location.
    > >>
    > >> The scripts that U-Boot runs determine where the image gets loaded into
    > >> memory.
    > >
    > > so instead of spending time on the uImage add simply the support the zImage to
    > > U-Boot as this AUTO_ZRELADDR have 0 advantage compare to the zImage
    > Thinking more about this, I guess the reliance on AUTO_ZRELADDR is wrong
    > here; Russell, Nico, is the ARM decompressor fully position-independent
    > irrespective of the AUTO_ZRELADDR setting.


    > That setting just determines where the decompressor writes its output,
    > not what address the decompressor can run at, right?


    > So, this KERNEL_NOLOAD feature could be
    > enabled in all cases on ARM, not only when AUTO_ZRELADDR is enabled.

    Except when CONFIG_ZBOOT_ROM is selected (if the uImage format
    allows it), or when the u-Boot environment doesn't know where to load
    the uImage.

    FWIW, I really hate this confusing usage of "noload" imposed on us by
    we know who. I thought better than contesting his definition though.

    But yes, AUTO_ZRELADDR has no effect on the location where the zImage
    should be _loaded_, except for the 128MB restriction.

    > As such to address Jean-Christophe's most recent comment above, this
    > patch isn't about adding support for AUTO_ZRELADDR, but for U-Boot's
    > kernel_noload feature, so comparisons should be drawn between
    > kernel_noload uImages and zImage, not between AUTO_ZRELADDR and zImage.
    > In other words:
    > We already have and need ZRELADDR no matter what, for reasons unrelated
    > to U-Boot/uImage.

    Well, I do have a patch series getting rid of ZRELADDR entirely, and
    AUTO_ZRELADDR would then become implicit, unless CONFIG_PHYS_OFFSET is


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