The NXP's i.MX EdgeLock Enclave, a HW IP creating an embedded secure enclave within the SoC boundary to enable features like - HSM - SHE - V2X Communicates via message unit with linux kernel. This driver is 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 can communicate on single MU. It exists on some i.MX processors. e.g. i.MX8ULP, i.MX93 etc. Signed-off-by: Pankaj Gupta <pankaj.gupta@xxxxxxx> --- .../bindings/firmware/fsl,imx-se-fw.yaml | 121 ++++++++++++++++++ 1 file changed, 121 insertions(+) create mode 100644 Documentation/devicetree/bindings/firmware/fsl,imx-se-fw.yaml diff --git a/Documentation/devicetree/bindings/firmware/fsl,imx-se-fw.yaml b/Documentation/devicetree/bindings/firmware/fsl,imx-se-fw.yaml new file mode 100644 index 000000000000..f7230f93e56d --- /dev/null +++ b/Documentation/devicetree/bindings/firmware/fsl,imx-se-fw.yaml @@ -0,0 +1,121 @@ +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/firmware/fsl,imx-se-fw.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: NXP i.MX EdgeLock Enclave Firmware (ELEFW) + +maintainers: + - Pankaj Gupta <pankaj.gupta@xxxxxxx> + +description: + The NXP's i.MX EdgeLock Enclave, a HW IP creating an embedded + secure enclave within the SoC boundary to enable features like + - HSM + - SHE + - V2X + + It uses message unit to communicate and coordinate to pass messages + (e.g., data, status and control) through its interfaces. + + This driver configures multiple misc-devices on the MU, to exchange + messages from User-space application and NXP's Edgelocke Enclave firmware. + The driver ensures that the messages must follow the following protocol + defined. + + Non-Secure + Secure + | + | + +---------+ +-------------+ | + | ele_mu.c+<---->+imx-mailbox.c| | + | | | mailbox.c +<-->+------+ +------+ + +---+-----+ +-------------+ | MU X +<-->+ ELE | + | +------+ +------+ + +----------------+ | + | | | + v v | + logical logical | + receiver waiter | + + + | + | | | + | | | + | +----+------+ | + | | | | + | | | | + device_ctx device_ctx device_ctx | + | + User 0 User 1 User Y | + +------+ +------+ +------+ | + |misc.c| |misc.c| |misc.c| | + kernel space +------+ +------+ +------+ | + | + +------------------------------------------------------ | + | | | | + 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. + +properties: + compatible: + enum: + - fsl,imx8ulp-se-fw + - fsl,imx93-se-fw + + mboxes: + description: + All MU channels must be within the same MU instance. Cross instances are + not allowed. Users need to ensure that used MU instance does not conflict + with other execution environments. + items: + - description: TX0 MU channel + - description: RX0 MU channel + + mbox-names: + items: + - const: tx + - const: rx + + fsl,mu-did: + $ref: /schemas/types.yaml#/definitions/uint32 + description: + By design, Domain is a clean separated processing island with separate power, + clocking and peripheral; but with a tightly integrated bus fabric for efficient + communication. The Domain to which this message-unit is associated, is identified + via Domain ID or did. + + sram-pool: + items: + - description: SRAM memory instance. + + memory-region: + items: + - description: Reserved memory region that can be accessed by firmware. Used for + exchanging the buffers between driver and firmware. + +required: + - compatible + - mboxes + - mbox-names + - mu-id + +additionalProperties: false + +examples: + - | + ele_fw: se-fw { + compatible = "fsl,imx8ulp-se-fw"; + mbox-names = "tx", "rx"; + mboxes = <&s4muap 0 0>, <&s4muap 1 0>; + fsl,mu-id = <2>; + }; -- 2.34.1
