[LEDE-DEV] [PATCH v2 0/6] intel-microcode: load as early as possible

[Tomasz Maciej Nowak]

This small series addresses current problem with late loading of Intel
microcode in OpenWrt. Following the commit messages [1] and later
discussion, late loading off the microcode can be ineffective for some
processors [2] and for others disabled [3]. Also it is discouraged for
any processor starting from Haswell and Silvermont.
Therefore this series converts the Intel microcode bundle to an initial
ram disk which is loaded with grub, so kernel has access to it as early
as possible.

1. https://lwn.net/Articles/530346
2. http://linux-kernel.vger.kernel.narkive.com/9XAb9Kw2/patch-v4-00-11-x86-microcode-early-load-microcode#post18
3. https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=723f2828a98c8ca19842042f418fb30dd8cfc0f7

Changes:
  - three new commits allowing buildsystem to properly handle packages
    installing files to /boot directory, mainly for x86 target:
    1) include/rootfs.mk: move boot directory for later use
    2) x86: mount writable bootfs
    3) x86: add packages files to image bootfs
  - uncomplicate test for AMD processors in:
    x86: add intel microcode entries to grub config
  - remove package specific hook in x86 image Makefile, remove
    postinst/prerm scripts and install microcode directly to /boot:
    intel-microcode: create early load microcode image
  - no changes:
    intel-microcode: remove dependency on iucode-tool

All changes sugested by Matthias Schiffer and Philip Prindeville.

Tomasz Maciej Nowak (6):
  include/rootfs.mk: move boot directory for later use
  x86: mount writable bootfs
  x86: add packages files to image bootfs
  intel-microcode: remove dependency on iucode-tool
  x86: add intel microcode entries to grub config
  intel-microcode: create early load microcode image

 include/rootfs.mk                                |  1 +
 package/firmware/intel-microcode/Makefile        | 16 +++++++++-------
 .../x86/base-files/lib/preinit/02_load_x86_ucode |  6 ++++--
 .../x86/base-files/lib/preinit/79_move_config    | 12 ++++--------
 target/linux/x86/image/Makefile                  |  6 ++++--
 target/linux/x86/image/grub-iso.cfg              |  3 +++
 target/linux/x86/image/grub.cfg                  |  3 +++
 7 files changed, 28 insertions(+), 19 deletions(-)

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2.17.0