RE: [EXT] Re: [PATCH v3 1/7] dt-bindings: arm: fsl: add mu binding doc

[Pankaj Gupta]

> -----Original Message-----
> From: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx>
> Sent: Friday, June 16, 2023 6:51 PM
> To: Pankaj Gupta <pankaj.gupta@xxxxxxx>; robh+dt@xxxxxxxxxx;
> krzysztof.kozlowski+dt@xxxxxxxxxx; conor+dt@xxxxxxxxxx;
> shawnguo@xxxxxxxxxx; s.hauer@xxxxxxxxxxxxxx; kernel@xxxxxxxxxxxxxx;
> festevam@xxxxxxxxx; dl-linux-imx <linux-imx@xxxxxxx>;
> devicetree@xxxxxxxxxxxxxxx; linux-arm-kernel@xxxxxxxxxxxxxxxxxxx; Gaurav
> Jain <gaurav.jain@xxxxxxx>; linux-kernel@xxxxxxxxxxxxxxx; Daniel Baluta
> <daniel.baluta@xxxxxxx>
> Subject: [EXT] Re: [PATCH v3 1/7] dt-bindings: arm: fsl: add mu binding doc
> 
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> 
> 
> 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@xxxxxxx>
> 
> 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@xxxxxxx>
> > +
> > +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