Re: [PATCH 0/4] crypto: nintendo-aes - add a new AES driver

From: Eric Biggers
Date: Tue Sep 21 2021 - 17:59:44 EST


On Tue, Sep 21, 2021 at 11:39:26PM +0200, Emmanuel Gil Peyrot wrote:
> This engine implements AES in CBC mode, using 128-bit keys only. It is
> present on both the Wii and the Wii U, and is apparently identical in
> both consoles.
>
> The hardware is capable of firing an interrupt when the operation is
> done, but this driver currently uses a busy loop, I’m not too sure
> whether it would be preferable to switch, nor how to achieve that.
>
> It also supports a mode where no operation is done, and thus could be
> used as a DMA copy engine, but I don’t know how to expose that to the
> kernel or whether it would even be useful.
>
> In my testing, on a Wii U, this driver reaches 80.7 MiB/s, while the
> aes-generic driver only reaches 30.9 MiB/s, so it is a quite welcome
> speedup.
>
> This driver was written based on reversed documentation, see:
> https://wiibrew.org/wiki/Hardware/AES
>
> Emmanuel Gil Peyrot (4):
> crypto: nintendo-aes - add a new AES driver
> dt-bindings: nintendo-aes: Document the Wii and Wii U AES support
> powerpc: wii.dts: Expose the AES engine on this platform
> powerpc: wii_defconfig: Enable AES by default

Does this pass the self-tests, including the fuzz tests which are enabled by
CONFIG_CRYPTO_MANAGER_EXTRA_TESTS=y?

- Eric