Re: [RFC PATCH 2/4] fpga: Add new properties to support user-key encrypted bitstream loading

From: Rob Herring
Date: Wed May 12 2021 - 22:31:10 EST


On Tue, May 04, 2021 at 03:52:25PM +0530, Nava kishore Manne wrote:
> This patch Adds ‘encrypted-key-name’ and
> ‘encrypted-user-key-fpga-config’ properties
> to support user-key encrypted bitstream loading
> use case.
>
> Signed-off-by: Nava kishore Manne <nava.manne@xxxxxxxxxx>
> ---
> Documentation/devicetree/bindings/fpga/fpga-region.txt | 5 +++++
> 1 file changed, 5 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/fpga/fpga-region.txt b/Documentation/devicetree/bindings/fpga/fpga-region.txt
> index d787d57491a1..957dc6cbcd9e 100644
> --- a/Documentation/devicetree/bindings/fpga/fpga-region.txt
> +++ b/Documentation/devicetree/bindings/fpga/fpga-region.txt
> @@ -177,6 +177,9 @@ Optional properties:
> it indicates that the FPGA has already been programmed with this image.
> If this property is in an overlay targeting a FPGA region, it is a
> request to program the FPGA with that image.
> +- encrypted-key-name : should contain the name of an encrypted key file located
> + on the firmware search path. It will be used to decrypt the FPGA image
> + file.
> - fpga-bridges : should contain a list of phandles to FPGA Bridges that must be
> controlled during FPGA programming along with the parent FPGA bridge.
> This property is optional if the FPGA Manager handles the bridges.
> @@ -187,6 +190,8 @@ Optional properties:
> - external-fpga-config : boolean, set if the FPGA has already been configured
> prior to OS boot up.
> - encrypted-fpga-config : boolean, set if the bitstream is encrypted
> +- encrypted-user-key-fpga-config : boolean, set if the bitstream is encrypted
> + with user key.

What's the relationship with encrypted-fpga-config? Both present or
mutually exclusive? Couldn't this be implied by encrypted-key-name being
present?

> - region-unfreeze-timeout-us : The maximum time in microseconds to wait for
> bridges to successfully become enabled after the region has been
> programmed.
> --
> 2.17.1
>