[U-Boot] [PATCH RESEND 2/2] cmd: fdt: add fdt overlay application subcommand

Simon Glass sjg at chromium.org
Sun May 1 20:55:07 CEST 2016


Hi Maxime,

On 4 April 2016 at 12:25, Maxime Ripard
<maxime.ripard at free-electrons.com> wrote:
> The device tree overlays are a good way to deal with user-modifyable
> boards or boards with some kind of an expansion mechanism where we can
> easily plug new board in (like the BBB or the raspberry pi).
>
> However, so far, the usual mechanism to deal with it was to have in Linux
> some driver detecting the expansion boards plugged in and then request
> these overlays using the firmware interface.
>
> That works in most cases, but in some cases, you might want to have the
> overlays applied before the userspace comes in. Either because the new
> board requires some kind of an early initialization, or because your root
> filesystem is accessed through that expansion board.
>
> The easiest solution in such a case is to simply have the component before
> Linux applying that overlay, removing all these drawbacks.
>
> Signed-off-by: Maxime Ripard <maxime.ripard at free-electrons.com>

Will there be a new version of this patch?

> ---
>  cmd/Makefile          |   2 +-
>  cmd/fdt.c             |  19 +++
>  cmd/fdt_overlay.c     | 464 ++++++++++++++++++++++++++++++++++++++++++++++++++
>  include/fdt_support.h |   2 +-
>  4 files changed, 485 insertions(+), 2 deletions(-)
>  create mode 100644 cmd/fdt_overlay.c

Regards,
Simon


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