Re: [RESEND PATCH 01/10] dt-bindings: crypto: k3: Add sa2ul bindings documentation

From: Rob Herring
Date: Mon Jul 22 2019 - 14:29:49 EST


On Fri, Jun 28, 2019 at 09:57:36AM +0530, Keerthy wrote:
> The series adds Crypto hardware accelerator support for SA2UL.
> SA2UL stands for security accelerator ultra lite.
>
> The Security Accelerator (SA2_UL) subsystem provides hardware
> cryptographic acceleration for the following use cases:
> â Encryption and authentication for secure boot
> â Encryption and authentication of content in applications
> requiring DRM (digital rights management) and
> content/asset protection
> The device includes one instantiation of SA2_UL named SA2_UL0
>
> SA2UL needs on tx channel and a pair of rx dma channels.
>
> Signed-off-by: Keerthy <j-keerthy@xxxxxx>
> ---
> .../devicetree/bindings/crypto/sa2ul.txt | 47 +++++++++++++++++++
> 1 file changed, 47 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/crypto/sa2ul.txt
>
> diff --git a/Documentation/devicetree/bindings/crypto/sa2ul.txt b/Documentation/devicetree/bindings/crypto/sa2ul.txt
> new file mode 100644
> index 000000000000..81cc039673b4
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/crypto/sa2ul.txt
> @@ -0,0 +1,47 @@
> +K3 SoC SA2UL crypto module
> +
> +Required properties:
> +
> +- compatible : Should be:
> + - "ti,sa2ul-crypto"

Needs to be SoC specific.

> +- reg : Offset and length of the register set for the module
> +
> +- dmas: DMA specifiers for tx and rx dma. sa2ul needs one tx channel
> + and 2 rx channels. First rx channel for < 256 bytes and
> + the other one for >=256 bytes. See the DMA client binding,
> + Documentation/devicetree/bindings/dma/dma.txt
> +- dma-names: DMA request names has to have one tx and 2 rx names
> + corresponding to dmas abive.
> +- ti,psil-config* - UDMA PSIL native Peripheral using packet mode.
> + SA2UL must have EPIB(Extended protocal information block)
> + and PSDATA(protocol specific data) properties.

If ti,needs-epib is required, then why do you need to specify it in DT?
In any case, this all seems like channel config info that should be part
of the #dma-cells.

Also, don't use vendor prefixes on node names.

> +
> +Example AM654 SA2UL:
> +crypto: crypto@4E00000 {
> + compatible = "ti,sa2ul-crypto";
> + reg = <0x0 0x4E00000 0x0 0x1200>;
> + ti,psil-base = <0x4000>;
> +
> + dmas = <&main_udmap &crypto 0 UDMA_DIR_TX>,
> + <&main_udmap &crypto 0 UDMA_DIR_RX>,
> + <&main_udmap &crypto 1 UDMA_DIR_RX>;
> + dma-names = "tx", "rx1", "rx2";
> +
> + ti,psil-config0 {
> + linux,udma-mode = <UDMA_PKT_MODE>;
> + ti,needs-epib;
> + ti,psd-size = <64>;
> + };
> +
> + ti,psil-config1 {
> + linux,udma-mode = <UDMA_PKT_MODE>;
> + ti,needs-epib;
> + ti,psd-size = <64>;
> + };
> +
> + ti,psil-config2 {
> + linux,udma-mode = <UDMA_PKT_MODE>;
> + ti,needs-epib;
> + ti,psd-size = <64>;
> + };
> +};
> --
> 2.17.1
>