• Dave Martin's avatar
    ARM: zImage/virt: hyp mode entry support for the zImage loader · 424e5994
    Dave Martin authored
    The zImage loader needs to turn on the MMU in order to take
    advantage of caching while decompressing the zImage.  Running this
    in hyp mode would require the LPAE pagetable format to be
    supported; to avoid this complexity, this patch switches out of hyp
    mode, and returns back to hyp mode just before booting the kernel.
    
    This implementation assumes that the Hyp mode view of memory and the
    PL1 view of memory are coherent, providing that the MMU and caches
    are off in both, as required by the boot protocol.  The zImage
    decompression code must drain the write buffer on completion anyway, and
    entry into Hyp mode should flush any prefetch buffer, avoiding hazards
    associated with local write buffers and the pipeline.
    Signed-off-by: default avatarDave Martin <dave.martin@linaro.org>
    Signed-off-by: default avatarMarc Zyngier <marc.zyngier@arm.com>
    424e5994
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