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From:   Ard Biesheuvel <ardb@kernel.org>
Date:   Mon, 31 Jul 2023 19:48:29 +0200
Message-ID: <CAMj1kXGXNbkxdDRNojtZD3NhMGK97LOchqGoM-4-tVLgH5JEiA@mail.gmail.com>
Subject: Re: [PATCH 0/5] Add support for Texas Instruments MCRC64 engine
To:     Kamlesh Gurudasani <kamlesh@ti.com>
Cc:     Herbert Xu <herbert@gondor.apana.org.au>,
        "David S. Miller" <davem@davemloft.net>,
        Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Conor Dooley <conor+dt@kernel.org>, Nishanth Menon <nm@ti.com>,
        Vignesh Raghavendra <vigneshr@ti.com>,
        Tero Kristo <kristo@kernel.org>,
        Catalin Marinas <catalin.marinas@arm.com>,
        Will Deacon <will@kernel.org>, linux-crypto@vger.kernel.org,
        linux-kernel@vger.kernel.org, devicetree@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org
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On Sun, 30 Jul 2023 at 20:56, Kamlesh Gurudasani <kamlesh@ti.com> wrote:
>
> Add support for MCRC64 engine to calculate 64-bit CRC in Full-CPU mode
>
> MCRC64 engine calculates 64-bit cyclic redundancy checks (CRC)
> according to the ISO 3309 standard.
>
> Generator polynomial: x^64 + x^4 + x^3 + x + 1
> Polynomial value: 0x000000000000001b
>

How will this code be used? WIthout a user of the crc64-iso crypto API
algorithm, there is no point in having a driver that implements it.

Also, *if* such a user exists, we'd need to have a generic C
implementation as well - we don't add new algorithms unless they can
be enabled on all platforms and architectures.


> Tested with
>
> and tcrypt,
> sudo modprobe tcrypt mode=329 sec=1
>
> Signed-off-by: Kamlesh Gurudasani <kamlesh@ti.com>
> ---
> Kamlesh Gurudasani (5):
>       crypto: crc64 - add crc64-iso test vectors
>       dt-bindings: crypto: Add binding for TI MCRC64 driver
>       crypto: ti - add driver for MCRC64 engine
>       arm64: dts: ti: k3-am62: Add dt node, cbass_main ranges for MCRC64
>       arm64: defconfig: enable MCRC module
>
>  Documentation/devicetree/bindings/crypto/ti,mcrc64.yaml |  42 +++++++
>  MAINTAINERS                                             |   7 ++
>  arch/arm64/boot/dts/ti/k3-am62-main.dtsi                |   7 ++
>  arch/arm64/boot/dts/ti/k3-am62.dtsi                     |   1 +
>  arch/arm64/configs/defconfig                            |   2 +
>  crypto/tcrypt.c                                         |   5 +
>  crypto/testmgr.c                                        |   7 ++
>  crypto/testmgr.h                                        | 401 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
>  drivers/crypto/Kconfig                                  |   1 +
>  drivers/crypto/Makefile                                 |   1 +
>  drivers/crypto/ti/Kconfig                               |  10 ++
>  drivers/crypto/ti/Makefile                              |   2 +
>  drivers/crypto/ti/mcrc64.c                              | 360 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
>  13 files changed, 846 insertions(+)
> ---
> base-commit: d7b3af5a77e8d8da28f435f313e069aea5bcf172
> change-id: 20230719-mcrc-upstream-7ae9a75cab37
>
> Best regards,
> --
> Kamlesh Gurudasani <kamlesh@ti.com>
>