Hi Raymond,
On Mon, 27 Nov 2023 at 12:53, Raymond Mao raymond.mao@linaro.org wrote:
From: Simon Glass sjg@chromium.org
Standard passage provides for a bloblist to be passed from one firmware phase to the next. That can be used to pass the devicetree along as well. If CONFIG_OF_BOARD is defined, a board custom routine will provide a bloblist or a specified memory address to retrieve the devicetree at runtime. A devicetree from a bloblist is prioritized than the one from specified memory region.
Tests for this will be added as part of the Universal Payload work.
Signed-off-by: Simon Glass sjg@chromium.org Co-developed-by: Raymond Mao raymond.mao@linaro.org Signed-off-by: Raymond Mao raymond.mao@linaro.org
Changes in v2
- New patch file created for v2. Amended from the original patch "[v2,30/32] fdt: Allow the devicetree to come from a bloblist". Remove CONFIG_OF_BLOBLIST and FDTSRC_BLOBLIST, a DTB from a previous loader is defined by CONFIG_OF_BOARD. The DTB can be located either in the bloblist or from a specified memory address.
doc/develop/devicetree/control.rst | 8 +++-- dts/Kconfig | 9 ++++-- include/fdtdec.h | 3 +- lib/fdtdec.c | 52 +++++++++++++++++++++++------- 4 files changed, 53 insertions(+), 19 deletions(-)
This is a bit mangled. I spoke to Ilias about this as osfc and thought we had it figured out, but it was a bit rushed so perhaps not.
OF_BOARD refers to a board-specific mechanism
We should have OF_BLOBLIST to reference to this, a standard mechanism and not board-specific.
Ideally all boards should use a bloblist to send their DT to U-Boot. E.g. Raspberry Pi.
So I believe my original patch was closer to what we want.
Regards, SImon