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    x86: ifdtool: Add support for early microcode access · 31eca697
    Simon Glass authored
    
    
    Some Intel CPUs use an 'FSP' binary blob which provides an inflexible
    means of starting up the CPU. One result is that microcode updates can only
    be done before RAM is available and therefore parsing of the device tree
    is impracticle.
    
    Worse, the addess of the microcode update must be stored in ROM since a
    pointer to its start address and size is passed to the 'FSP' blob. It is
    not possible to perform any calculations to obtain the address and size.
    
    To work around this, ifdtool is enhanced to work out the address and size of
    the first microcode update it finds in the supplied device tree. It then
    writes these into the correct place in the ROM. U-Boot can then start up
    the FSP correctly.
    
    Signed-off-by: default avatarSimon Glass <sjg@chromium.org>
    Reviewed-by: default avatarBin Meng <bmeng.cn@gmail.com>
    31eca697