Re: [PATCH v5 01/11] dt-bindings: arm: fsl: add imx-se-fw binding doc

From: Krzysztof Kozlowski
Date: Thu Aug 24 2023 - 14:46:43 EST


On 23/08/2023 14:43, Rob Herring wrote:
>> + |
>> + +------------------------------------------------------ |
>> + | | | |
>> + userspace /dev/ele_muXch0 | | |
>> + /dev/ele_muXch1 | |
>> + /dev/ele_muXchY |
>> + |
>> +
>> + When a user sends a command to the firmware, it registers its device_ctx
>> + as waiter of a response from firmware.
>> +
>> + A user can be registered as receiver of command from the ELE.
>> + Create char devices in /dev as channels of the form /dev/ele_muXchY with X
>> + the id of the driver and Y for each users. It allows to send and receive
>> + messages to the NXP EdgeLock Enclave IP firmware on NXP SoC, where current
>> + possible value, i.e., supported SoC(s) are imx8ulp, imx93.
>
> Looks like a bunch of Linux details which don't belong in the binding.
>
> Why do you need your own custom interface to userspace? No one else has
> a similar feature in their platforms? Something like virtio or rpmsg
> doesn't work?

+Cc Greg,

I doubt they care. This is some stub-driver to pass messages from
user-space to the firmware. The interface is undocumented, without
examples and no user-space user.

Best regards,
Krzysztof