On Mon, Aug 28, 2023 at 5:20 PM Simon Glass sjg@chromium.org wrote:
Hi,
On Sat, 26 Aug 2023 at 03:07, Sughosh Ganu sughosh.ganu@linaro.org wrote:
Provide a way for removing certain devicetree nodes and/or properties from the devicetree. This is needed to purge certain nodes and properties which may be relevant only in U-Boot. Such nodes and properties are then removed from the devicetree before it is passed to the kernel. This ensures that the devicetree passed to the OS does not contain any non-compliant nodes and properties.
The removal of the nodes and properties is being done through an EVT_FT_FIXUP handler. I am not sure if the removal code needs to be behind any Kconfig symbol.
I have only build tested this on sandbox, and tested on qemu arm64 virt platform. This being a RFC, I have not put this through a CI run.
Sughosh Ganu (5): dt: Provide a way to remove non-compliant nodes and properties fwu: Add the fwu-mdata node for removal from devicetree capsule: Add the capsule-key property for removal from devicetree bootefi: Call the EVT_FT_FIXUP event handler doc: Add a document for non-compliant DT node/property removal
cmd/bootefi.c | 18 +++++ .../devicetree/dt_non_compliant_purge.rst | 64 ++++++++++++++++ drivers/fwu-mdata/fwu-mdata-uclass.c | 5 ++ include/dt-structs.h | 11 +++ lib/Makefile | 1 + lib/dt_purge.c | 73 +++++++++++++++++++ lib/efi_loader/efi_capsule.c | 7 ++ 7 files changed, 179 insertions(+) create mode 100644 doc/develop/devicetree/dt_non_compliant_purge.rst create mode 100644 lib/dt_purge.c
What is the point of removing them? Instead, we should make sure that we upstream the bindings and encourage SoC vendors to sync them. If we remove them, no one will bother and U-Boot just becomes a dumping ground.
Well things like the binman entries in DT are U-Boot specific and not useful for HW related descriptions or for Linux or another OS being able to deal with HW so arguably we're already a dumping ground to some degree for not defining hardware.
Instead of this, how about working on bringing the DT validation into U-Boot so we can see what state things are in?
Please send the bindings for Linaro's recent series (which I suspect are motivating this series) so we can start the process.
Regards, Simon