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    SubjectRe: [PATCH 2/3] Kbuild: Implement CONFIG_UIMAGE_KERNEL_NOLOAD
    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 <swarren@wwwdotorg.org>
    >>>> ---
    >>>> 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.

    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.

    Patch 1 in this series is just consolidating duplicate definitions, and
    doesn't introduce any new features, so I think hope you think it's a
    good thing no matter what anyone thinks about U-Boot/uImage.

    I assume you're only arguing about patches 2 and 3?


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