linux-kernel - Re: [PATCH v3 1/6] dt-bindings: crypto: Document support for SPAcc

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <3570be5b-cb20-4259-9a9b-959098b902d0@kernel.org>
Date: Tue, 3 Jun 2025 14:04:38 +0200
From: Krzysztof Kozlowski <krzk@...nel.org>
To: Pavitrakumar Managutte <pavitrakumarm@...avyalabs.com>
Cc: linux-crypto@...r.kernel.org, linux-kernel@...r.kernel.org,
 devicetree@...r.kernel.org, herbert@...dor.apana.org.au, robh@...nel.org,
 krzk+dt@...nel.org, conor+dt@...nel.org, Ruud.Derwig@...opsys.com,
 manjunath.hadli@...avyalabs.com, adityak@...avyalabs.com,
 Bhoomika Kadabi <bhoomikak@...avyalabs.com>
Subject: Re: [PATCH v3 1/6] dt-bindings: crypto: Document support for SPAcc

On 03/06/2025 13:45, Pavitrakumar Managutte wrote:
> Hi Krzysztof,
>   Thanks for the inputs, my comments are embedded below.
> 
> Warm regards,
> PK
> 
> On Mon, Jun 2, 2025 at 11:28 AM Krzysztof Kozlowski <krzk@...nel.org> wrote:
>>
>> On 02/06/2025 07:32, Pavitrakumar Managutte wrote:
>>> Add DT bindings related to the SPAcc driver for Documentation.
>>> DWC Synopsys Security Protocol Accelerator(SPAcc) Hardware Crypto
>>> Engine is a crypto IP designed by Synopsys.
>>>
>>> Co-developed-by: Bhoomika Kadabi <bhoomikak@...avyalabs.com>
>>> Signed-off-by: Bhoomika Kadabi <bhoomikak@...avyalabs.com>
>>> Signed-off-by: Pavitrakumar Managutte <pavitrakumarm@...avyalabs.com>
>>> Acked-by: Ruud Derwig <Ruud.Derwig@...opsys.com>
>>
>> Where was this Ack given? It's not on the lists, it's not public, so it
>> cannot be after your SoB.
> 
> PK: Yes, its not on the mailing list. I will remove that.

If it was given in private, then happened for sure before you sent the
patch, so it should be above your SoB.

...

>>> +
>>> +  snps,vspacc-id:
>>> +    $ref: /schemas/types.yaml#/definitions/uint32
>>> +    description: |
>>> +      Virtual SPAcc instance identifier.
>>> +      The SPAcc hardware supports multiple virtual instances (determined by
>>> +      ELP_SPACC_CONFIG_VSPACC_CNT parameter), and this ID is used to identify
>>> +      which virtual instance this node represents.
>>
>> No, IDs are not accepted.
> 
> PK: This represents the specific virtual SPAcc that is being used in
> the current configuration. It is used to index into the register banks
> and the context memories of the virtual SPAcc that is being used. The
> SPAcc IP can be configured as dedicated virtual SPAccs in
> heterogeneous environments.

OK. Why registers are not narrowed to only this instance? It feels like
you provide here full register space for multiple devices and then
select the bank with above ID.


> This was also discssed with Rob Herring and updated from
> "vpsacc-index" to "vspacc-id" based on Rob's inputs
> https://lore.kernel.org/linux-crypto/CALxtO0mkmyaDYta0tfx9Q1qi_GY0OwUoFDDVmcL15UH_fEZ25w@mail.gmail.com/

Yeah, it is still ID and thus look at his comment about proper
justification.

> 
>>
>>> +    minimum: 0
>>> +    maximum: 7
>>> +
>>> +  snps,spacc-internal-counter:
>>> +    $ref: /schemas/types.yaml#/definitions/uint32
>>> +    description: |
>>> +      Hardware counter that generates an interrupt based on a count value.
>>> +      This counter starts ticking when there is a completed job sitting on
>>> +      the status fifo to be serviced. This makes sure that no jobs are
>>> +      starved of processing.
>>
>> Not a DT property.
> 
> PK: This is a hardware counter which starts ticking when a processed
> job is sitting on the STAT FIFO. This makes sure a JOB does not stay
> in STATUS FIFO unprocessed.
> 
> This was called watchdog timer - wdtimer, which we renamed to
> "spacc-internal-counter" based on your inputs.
> https://lore.kernel.org/linux-crypto/CALxtO0k4RkopERap_ykrMTZ4Qtdzm8hEPJGLCQ2pknQGjfQ4Eg@mail.gmail.com/

I suggested to use watchdog schema if this device has a watchdog feature.

Why would you configure here different values for the same hardware in
different boards?



Best regards,
Krzysztof