diff mbox series

[v3,1/7] dt-bindings: arm: fsl: add mu binding doc

Message ID 20230616181144.646500-2-pankaj.gupta@nxp.com (mailing list archive)
State New, archived
Headers show
Series firmware: imx: NXP Edgelock Enclave MUAP Driver | expand

Commit Message

Pankaj Gupta June 16, 2023, 6:11 p.m. UTC
The NXP i.MX Message Unit enables two processing elements
to communicate & co-ordinate with each other. This driver
is used to communicate between Application Core and
NXP HSM IPs like NXP EdgeLock Enclave etc.
It exists on some i.MX processors. e.g. i.MX8ULP, i.MX93 etc.

Signed-off-by: Pankaj Gupta <pankaj.gupta@nxp.com>
---
 .../bindings/arm/freescale/fsl,ele_mu.yaml    | 144 ++++++++++++++++++
 1 file changed, 144 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/arm/freescale/fsl,ele_mu.yaml

Comments

Krzysztof Kozlowski June 16, 2023, 1:21 p.m. UTC | #1
On 16/06/2023 20:11, Pankaj Gupta wrote:
> The NXP i.MX Message Unit enables two processing elements
> to communicate & co-ordinate with each other. This driver
> is used to communicate between Application Core and
> NXP HSM IPs like NXP EdgeLock Enclave etc.
> It exists on some i.MX processors. e.g. i.MX8ULP, i.MX93 etc.
> 
> Signed-off-by: Pankaj Gupta <pankaj.gupta@nxp.com>

I don't see reply to Daniel's concerns.

I don't see improvements here based on the previous review you received.
It seems you just ignored everything, right?

Limited review follows up because binding is not in the shape for
upstream. Do some internal reviews prior sending it.

> ---
>  .../bindings/arm/freescale/fsl,ele_mu.yaml    | 144 ++++++++++++++++++
>  1 file changed, 144 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/arm/freescale/fsl,ele_mu.yaml
> 
> diff --git a/Documentation/devicetree/bindings/arm/freescale/fsl,ele_mu.yaml b/Documentation/devicetree/bindings/arm/freescale/fsl,ele_mu.yaml
> new file mode 100644
> index 000000000000..29e309a88899
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/arm/freescale/fsl,ele_mu.yaml

No underscores, filename based on compatibles.

> @@ -0,0 +1,144 @@
> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/arm/freescale/fsl,ele_mu.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: NXP i.MX EdgeLock Enclave MUAP driver

Drop driver.

> +
> +maintainers:
> +  - Pankaj Gupta <pankaj.gupta@nxp.com>
> +
> +description: |
> +
> +  NXP i.MX EdgeLock Enclave Message Unit Driver.
> +  The Messaging Unit module enables two processing elements within the SoC to
> +  communicate and coordinate by passing messages (e.g., data, status and control)
> +  through its interfaces.
> +
> +  The NXP i.MX EdgeLock Enclave Message Unit (ELE-MUAP) is specifically targeted
> +  for use between application core and Edgelocke Enclave. It allows to send
> +  messages to the EL Enclave using a shared mailbox.
> +
> +  The messages must follow the 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 ELE, it registers its device_ctx as
> +  waiter of a response from ELE.
> +
> +  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 on NXP SoC, where current possible
> +  value, i.e., supported SoC(s) are imx8ulp, imx93.
> +
> +properties:
> +  compatible:
> +    enum:
> +      - fsl,imx-ele
> +      - fsl,imx93-ele
> +
> +  mboxes:
> +    description:
> +      A list of phandles of TX MU channels followed by a list of phandles of
> +      RX MU channels. The number of expected tx and rx channels is 1 TX, and
> +      1 RX channels. All MU channels must be within the same MU instance.
> +      Cross instances are not allowed. The MU instance to be used is S4MUAP
> +      for imx8ulp & imx93. 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,ele_mu_did:

No underscores. Drop all properties not related to hardware.


> +    description:
> +      Owner of message-unit, is identified via Domain ID or did.
> +    allOf:
> +      - $ref: /schemas/types.yaml#/definitions/uint32
> +      - enum: [0, 1, 2, 3, 4, 5, 6, 7]

That's not the syntax you can find. Open example-schema and rewrite your
bindings.


> +
> +examples:
> +  - |
> +    ele_mu: ele_mu {

Node names should be generic. See also explanation and list of examples
in DT specification:
https://devicetree-specification.readthedocs.io/en/latest/chapter2-devicetree-basics.html#generic-names-recommendation

> +      compatible = "fsl,imx93-ele";
> +      mbox-names = "tx", "rx";
> +      mboxes = <&s4muap 2 0
> +                &s4muap 3 0>;
> +      fsl,ele_mu_id = <1>;
> +      fsl,ele_max_users = <4>;
> +      fsl,cmd_tag = /bits/ 8 <0x17>;
> +      fsl,rsp_tag = /bits/ 8 <0xe1>;
> +    };

Best regards,
Krzysztof
Pankaj Gupta July 10, 2023, 5:52 p.m. UTC | #2
> -----Original Message-----
> From: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
> Sent: Friday, June 16, 2023 6:51 PM
> To: Pankaj Gupta <pankaj.gupta@nxp.com>; robh+dt@kernel.org;
> krzysztof.kozlowski+dt@linaro.org; conor+dt@kernel.org;
> shawnguo@kernel.org; s.hauer@pengutronix.de; kernel@pengutronix.de;
> festevam@gmail.com; dl-linux-imx <linux-imx@nxp.com>;
> devicetree@vger.kernel.org; linux-arm-kernel@lists.infradead.org; Gaurav
> Jain <gaurav.jain@nxp.com>; linux-kernel@vger.kernel.org; Daniel Baluta
> <daniel.baluta@nxp.com>
> Subject: [EXT] Re: [PATCH v3 1/7] dt-bindings: arm: fsl: add mu binding doc
> 
> Caution: This is an external email. Please take care when clicking links or
> opening attachments. When in doubt, report the message using the 'Report
> this email' button
> 
> 
> On 16/06/2023 20:11, Pankaj Gupta wrote:
> > The NXP i.MX Message Unit enables two processing elements to
> > communicate & co-ordinate with each other. This driver is used to
> > communicate between Application Core and NXP HSM IPs like NXP
> EdgeLock
> > Enclave etc.
> > It exists on some i.MX processors. e.g. i.MX8ULP, i.MX93 etc.
> >
> > Signed-off-by: Pankaj Gupta <pankaj.gupta@nxp.com>
> 
> I don't see reply to Daniel's concerns.
> 
> I don't see improvements here based on the previous review you received.
> It seems you just ignored everything, right?
Replied to Daniel's concern.

> 
> Limited review follows up because binding is not in the shape for upstream.
> Do some internal reviews prior sending it.
Done the internal review.

> 
> > ---
> >  .../bindings/arm/freescale/fsl,ele_mu.yaml    | 144 ++++++++++++++++++
> >  1 file changed, 144 insertions(+)
> >  create mode 100644
> > Documentation/devicetree/bindings/arm/freescale/fsl,ele_mu.yaml
> >
> > diff --git
> > a/Documentation/devicetree/bindings/arm/freescale/fsl,ele_mu.yaml
> > b/Documentation/devicetree/bindings/arm/freescale/fsl,ele_mu.yaml
> > new file mode 100644
> > index 000000000000..29e309a88899
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/arm/freescale/fsl,ele_mu.yaml
> 
> No underscores, filename based on compatibles.

Accepted. Will correct in V4.

> 
> > @@ -0,0 +1,144 @@
> > +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause) %YAML 1.2
> > +---
> > +$id:
> >
> +https://eur01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fdevi
> >
> +cetree.org%2Fschemas%2Farm%2Ffreescale%2Ffsl%2Cele_mu.yaml%23&d
> ata=05
> >
> +%7C01%7Cpankaj.gupta%40nxp.com%7C72b9e18a32a342bcf68c08db6e6c
> 8d5a%7C6
> >
> +86ea1d3bc2b4c6fa92cd99c5c301635%7C0%7C0%7C638225184750511073
> %7CUnknow
> >
> +n%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1h
> aWwiL
> >
> +CJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=5quVB0LAMCdjYghThl6PSI3
> CJPfuGtVoW
> > +AtN1gr4xm0%3D&reserved=0
> > +$schema:
> >
> +https://eur01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fdevi
> > +cetree.org%2Fmeta-
> schemas%2Fcore.yaml%23&data=05%7C01%7Cpankaj.gupta%
> >
> +40nxp.com%7C72b9e18a32a342bcf68c08db6e6c8d5a%7C686ea1d3bc2b4c
> 6fa92cd9
> >
> +9c5c301635%7C0%7C0%7C638225184750511073%7CUnknown%7CTWFpb
> GZsb3d8eyJWI
> >
> +joiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7
> C3000%
> >
> +7C%7C%7C&sdata=GyUGJThMnxLNEQX1guW9Q%2BdoVjMrvn%2FSupgJ7tu
> fkXk%3D&res
> > +erved=0
> > +
> > +title: NXP i.MX EdgeLock Enclave MUAP driver
> 
> Drop driver.

Accepted. Will correct in V4.

> 
> > +
> > +maintainers:
> > +  - Pankaj Gupta <pankaj.gupta@nxp.com>
> > +
> > +description: |
> > +
> > +  NXP i.MX EdgeLock Enclave Message Unit Driver.
> > +  The Messaging Unit module enables two processing elements within
> > + the SoC to  communicate and coordinate by passing messages (e.g.,
> > + data, status and control)  through its interfaces.
> > +
> > +  The NXP i.MX EdgeLock Enclave Message Unit (ELE-MUAP) is
> > + specifically targeted  for use between application core and
> > + Edgelocke Enclave. It allows to send  messages to the EL Enclave using a
> shared mailbox.
> > +
> > +  The messages must follow the 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 ELE, it registers its device_ctx
> > + as  waiter of a response from ELE.
> > +
> > +  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 on NXP SoC,
> > + where current possible  value, i.e., supported SoC(s) are imx8ulp, imx93.
> > +
> > +properties:
> > +  compatible:
> > +    enum:
> > +      - fsl,imx-ele
> > +      - fsl,imx93-ele
> > +
> > +  mboxes:
> > +    description:
> > +      A list of phandles of TX MU channels followed by a list of phandles of
> > +      RX MU channels. The number of expected tx and rx channels is 1 TX,
> and
> > +      1 RX channels. All MU channels must be within the same MU instance.
> > +      Cross instances are not allowed. The MU instance to be used is
> S4MUAP
> > +      for imx8ulp & imx93. 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,ele_mu_did:
> 
> No underscores. Drop all properties not related to hardware.
Accepted. Will correct in V4.

> 
> 
> > +    description:
> > +      Owner of message-unit, is identified via Domain ID or did.
> > +    allOf:
> > +      - $ref: /schemas/types.yaml#/definitions/uint32
> > +      - enum: [0, 1, 2, 3, 4, 5, 6, 7]
> 
> That's not the syntax you can find. Open example-schema and rewrite your
> bindings.
Accepted. Will correct in V4.

Change it to:
+    $ref: /schemas/types.yaml#/definitions/uint32
+    description:
+      Owner of message-unit, is identified via Domain ID or did.

> 
> 
> > +
> > +examples:
> > +  - |
> > +    ele_mu: ele_mu {
> 
> Node names should be generic. See also explanation and list of examples in
> DT specification:
> https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fdevic
> etree-specification.readthedocs.io%2Fen%2Flatest%2Fchapter2-devicetree-
> basics.html%23generic-names-
> recommendation&data=05%7C01%7Cpankaj.gupta%40nxp.com%7C72b9e1
> 8a32a342bcf68c08db6e6c8d5a%7C686ea1d3bc2b4c6fa92cd99c5c301635%7
> C0%7C0%7C638225184750511073%7CUnknown%7CTWFpbGZsb3d8eyJWIjoi
> MC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C30
> 00%7C%7C%7C&sdata=wvrm2b84xq6KYEIEEGm9%2BCAHaDsXOfKlLvamsjh3
> jTg%3D&reserved=0
> 	
Accepted. Will correct in V4.
Will use the generic name "se-fw" for "secure-enclave firmware", instead of "ele-mu"

> > +      compatible = "fsl,imx93-ele";
> > +      mbox-names = "tx", "rx";
> > +      mboxes = <&s4muap 2 0
> > +                &s4muap 3 0>;
> > +      fsl,ele_mu_id = <1>;
Used generic name and changed from "ele_mu_id" to "mu-id"

> > +      fsl,ele_max_users = <4>;
> > +      fsl,cmd_tag = /bits/ 8 <0x17>;
> > +      fsl,rsp_tag = /bits/ 8 <0xe1>;
Removed the above 3 non-hw defined bindings.

> > +    };
> 
> Best regards,
> Krzysztof
Krzysztof Kozlowski July 12, 2023, 6:41 p.m. UTC | #3
On 16/06/2023 15:21, Krzysztof Kozlowski wrote:
>> +  mbox-names:
>> +    items:
>> +      - const: tx
>> +      - const: rx
>> +
>> +  fsl,ele_mu_did:
> 
> No underscores. Drop all properties not related to hardware.

How is this related to hardware?

Best regards,
Krzysztof
Krzysztof Kozlowski July 12, 2023, 6:42 p.m. UTC | #4
On 10/07/2023 19:52, Pankaj Gupta wrote:
> 
> 
>> -----Original Message-----
>> From: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
>> Sent: Friday, June 16, 2023 6:51 PM
>> To: Pankaj Gupta <pankaj.gupta@nxp.com>; robh+dt@kernel.org;
>> krzysztof.kozlowski+dt@linaro.org; conor+dt@kernel.org;
>> shawnguo@kernel.org; s.hauer@pengutronix.de; kernel@pengutronix.de;
>> festevam@gmail.com; dl-linux-imx <linux-imx@nxp.com>;
>> devicetree@vger.kernel.org; linux-arm-kernel@lists.infradead.org; Gaurav
>> Jain <gaurav.jain@nxp.com>; linux-kernel@vger.kernel.org; Daniel Baluta
>> <daniel.baluta@nxp.com>
>> Subject: [EXT] Re: [PATCH v3 1/7] dt-bindings: arm: fsl: add mu binding doc
>>
>> Caution: This is an external email. Please take care when clicking links or
>> opening attachments. When in doubt, report the message using the 'Report
>> this email' button
>>
>>
>> On 16/06/2023 20:11, Pankaj Gupta wrote:
>>> The NXP i.MX Message Unit enables two processing elements to
>>> communicate & co-ordinate with each other. This driver is used to
>>> communicate between Application Core and NXP HSM IPs like NXP
>> EdgeLock
>>> Enclave etc.
>>> It exists on some i.MX processors. e.g. i.MX8ULP, i.MX93 etc.
>>>
>>> Signed-off-by: Pankaj Gupta <pankaj.gupta@nxp.com>
>>
>> I don't see reply to Daniel's concerns.
>>
>> I don't see improvements here based on the previous review you received.
>> It seems you just ignored everything, right?
> Replied to Daniel's concern.
> 
>>
>> Limited review follows up because binding is not in the shape for upstream.
>> Do some internal reviews prior sending it.
> Done the internal review.

I doubt. Your v4 bindings and DTS were not tested. v4 Driver has trivial
issues.

Best regards,
Krzysztof
diff mbox series

Patch

diff --git a/Documentation/devicetree/bindings/arm/freescale/fsl,ele_mu.yaml b/Documentation/devicetree/bindings/arm/freescale/fsl,ele_mu.yaml
new file mode 100644
index 000000000000..29e309a88899
--- /dev/null
+++ b/Documentation/devicetree/bindings/arm/freescale/fsl,ele_mu.yaml
@@ -0,0 +1,144 @@ 
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/arm/freescale/fsl,ele_mu.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: NXP i.MX EdgeLock Enclave MUAP driver
+
+maintainers:
+  - Pankaj Gupta <pankaj.gupta@nxp.com>
+
+description: |
+
+  NXP i.MX EdgeLock Enclave Message Unit Driver.
+  The Messaging Unit module enables two processing elements within the SoC to
+  communicate and coordinate by passing messages (e.g., data, status and control)
+  through its interfaces.
+
+  The NXP i.MX EdgeLock Enclave Message Unit (ELE-MUAP) is specifically targeted
+  for use between application core and Edgelocke Enclave. It allows to send
+  messages to the EL Enclave using a shared mailbox.
+
+  The messages must follow the 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 ELE, it registers its device_ctx as
+  waiter of a response from ELE.
+
+  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 on NXP SoC, where current possible
+  value, i.e., supported SoC(s) are imx8ulp, imx93.
+
+properties:
+  compatible:
+    enum:
+      - fsl,imx-ele
+      - fsl,imx93-ele
+
+  mboxes:
+    description:
+      A list of phandles of TX MU channels followed by a list of phandles of
+      RX MU channels. The number of expected tx and rx channels is 1 TX, and
+      1 RX channels. All MU channels must be within the same MU instance.
+      Cross instances are not allowed. The MU instance to be used is S4MUAP
+      for imx8ulp & imx93. 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,ele_mu_did:
+    description:
+      Owner of message-unit, is identified via Domain ID or did.
+    allOf:
+      - $ref: /schemas/types.yaml#/definitions/uint32
+      - enum: [0, 1, 2, 3, 4, 5, 6, 7]
+
+  fsl,ele_mu_id:
+    description:
+      Identifier to the message-unit among the multiple message-unit that exists on SoC.
+      It is used to create the channels, default to 2
+    allOf:
+      - $ref: /schemas/types.yaml#/definitions/uint32
+      - enum: [0, 1, 2, 3]
+
+  fsl,ele_max_users:
+    description:
+      Number of misclleneous devices to be created, default to 4
+    allOf:
+      - $ref: /schemas/types.yaml#/definitions/uint32
+      - enum: [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
+
+  fsl,cmd_tag:
+    description:
+      Tag in message header for commands on this MU, default to 0x17
+    allOf:
+      - $ref: /schemas/types.yaml#/definitions/uint8
+      - enum: [0x17, 0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e]
+
+  fsl,rsp_tag:
+    description:
+      Tag in message header for responses on this MU, default to 0xe1
+    allOf:
+      - $ref: /schemas/types.yaml#/definitions/uint8
+      - enum: [0xe1, 0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7, 0xe8]
+
+required:
+  - compatible
+  - mboxes
+  - mbox-names
+
+additionalProperties: false
+
+examples:
+  - |
+    ele_mu: ele_mu {
+      compatible = "fsl,imx93-ele";
+      mbox-names = "tx", "rx";
+      mboxes = <&s4muap 2 0
+                &s4muap 3 0>;
+      fsl,ele_mu_id = <1>;
+      fsl,ele_max_users = <4>;
+      fsl,cmd_tag = /bits/ 8 <0x17>;
+      fsl,rsp_tag = /bits/ 8 <0xe1>;
+    };