[PATCH v3 1/1] wcn36xx: Add RX frame SNR as a source of system entropy

[Kalle Valo]

Bryan O'Donoghue <bryan.odonoghue at linaro.org> wrote:

> The signal-to-noise-ratio SNR is returned by the wcn36xx firmware for each
> received frame. SNR represents all of the unwanted interference signal
> after filtering out the fundamental frequency and harmonics of the
> frequency.
> 
> Noise can come from various electromagnetic sources, from temperature
> affecting the performance hardware components or quantization effects
> converting from analog to digital domains.
> 
> The SNR value returned by the WiFi firmware then is a good source of
> entropy.
> 
> Other WiFi drivers offer up the noise component of the FFT as an entropy
> source for the random pool e.g.
> 
> commit 2aa56cca3571 ("ath9k: Mix the received FFT bins to the random pool")
> 
> I attended Jason's talk on sources of randomness at Plumbers and it
> occurred to me that SNR is a reasonable candidate to add.
> 
> Cc: Jason A. Donenfeld <Jason at zx2c4.com>
> Signed-off-by: Bryan O'Donoghue <bryan.odonoghue at linaro.org>
> Signed-off-by: Kalle Valo <quic_kvalo at quicinc.com>

Patch applied to ath-next branch of ath.git, thanks.

e1a6b5d3a971 wifi: wcn36xx: Add RX frame SNR as a source of system entropy

-- 
https://patchwork.kernel.org/project/linux-wireless/patch/20220915004117.1562703-2-bryan.odonoghue@linaro.org/

https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches