[PATCH v17 2/7] dt-bindings: arm: fsl: add imx-se-fw binding doc

Pankaj Gupta
2025-04-25T15:18:17Z

The NXP security hardware IP(s) like: i.MX EdgeLock Enclave, V2X etc.,
creates an embedded secure enclave within the SoC boundary to enable
features like:
- HSM
- SHE
- V2X

Secure-Enclave(s) communication interface are typically via message
unit, i.e., based on mailbox linux kernel driver. This driver enables
communication ensuring well defined message sequence protocol between
Application Core and enclave's firmware.

Driver configures multiple misc-device on the MU, for multiple
user-space applications, to be able to communicate over single MU.

It exists on some i.MX processors. e.g. i.MX8ULP, i.MX93 etc.

Signed-off-by: Pankaj Gupta <pankaj.gupta@nxp.com>
Reviewed-by: Rob Herring (Arm) <robh@kernel.org>
---
Changes from v13 to v14:
- No changed.

Changes from v12 to v13:
- compatible string is modified from "fsl,imx8ulp-se" to "fsl,imx8ulp-se-ele-hsm".
- compatible string is modified from "fsl,imx93-se" to "fsl,imx93-se-ele-hsm".
- compatible string is modified from "fsl,imx95-se" to "fsl,imx95-se-ele-hsm".
- Mis-understood the +1 from Conor. Hence dropped the Reviewed-by tag.
- Collected Rob's R-b tag on v7 (https://lore.kernel.org/all/172589152997.4184616.5889493628960272898.robh@kernel.org/)
---
.../devicetree/bindings/firmware/fsl,imx-se.yaml | 91 ++++++++++++++++++++++
1 file changed, 91 insertions(+)

diff --git a/Documentation/devicetree/bindings/firmware/fsl,imx-se.yaml b/Documentation/devicetree/bindings/firmware/fsl,imx-se.yaml
new file mode 100644
index 000000000000..fa81adbf9b80
--- /dev/null
+++ b/Documentation/devicetree/bindings/firmware/fsl,imx-se.yaml
@@ -0,0 +1,91 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/firmware/fsl,imx-se.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: NXP i.MX HW Secure Enclave(s) EdgeLock Enclave
+
+maintainers:
+ - Pankaj Gupta <pankaj.gupta@nxp.com>
+
+description: |
+ NXP's SoC may contain one or multiple embedded secure-enclave HW
+ IP(s) like i.MX EdgeLock Enclave, V2X etc. These NXP's HW IP(s)
+ enables features like
+ - Hardware Security Module (HSM),
+ - Security Hardware Extension (SHE), and
+ - Vehicular to Anything (V2X)
+
+ Communication interface to the secure-enclaves(se) is based on the
+ messaging unit(s).
+
+properties:
+ compatible:
+ enum:
+ - fsl,imx8ulp-se-ele-hsm
+ - fsl,imx93-se-ele-hsm
+ - fsl,imx95-se-ele-hsm
+
+ mboxes:
+ items:
+ - description: mailbox phandle to send message to se firmware
+ - description: mailbox phandle to receive message from se firmware
+
+ mbox-names:
+ items:
+ - const: tx
+ - const: rx
+
+ memory-region:
+ maxItems: 1
+
+ sram:
+ maxItems: 1
+
+required:
+ - compatible
+ - mboxes
+ - mbox-names
+
+allOf:
+ # memory-region
+ - if:
+ properties:
+ compatible:
+ contains:
+ enum:
+ - fsl,imx8ulp-se-ele-hsm
+ - fsl,imx93-se-ele-hsm
+ then:
+ required:
+ - memory-region
+ else:
+ properties:
+ memory-region: false
+
+ # sram
+ - if:
+ properties:
+ compatible:
+ contains:
+ enum:
+ - fsl,imx8ulp-se-ele-hsm
+ then:
+ required:
+ - sram
+
+ else:
+ properties:
+ sram: false
+
+additionalProperties: false
+
+examples:
+ - |
+ secure-enclave {
+ compatible = "fsl,imx95-se-ele-hsm";
+ mboxes = <&ele_mu0 0 0>, <&ele_mu0 1 0>;
+ mbox-names = "tx", "rx";
+ };
+...

--
2.43.0