Subject: Re: [PATCH net v5 1/6] net: dsa: mt7530: set all CPU ports in MT7531_CPU_PMAP

From: "Russell King (Oracle)" <[email-masked]>
Date: Fri, 16 Jun 2023 11:07:24 +0100

On Fri, Jun 16, 2023 at 05:53:22AM +0300, [email-masked] wrote:
> From: Arınç ÜNAL <[email-masked]>
> 
> MT7531_CPU_PMAP represents the destination port mask for trapped-to-CPU
> frames (further restricted by PCR_MATRIX).
> 
> Currently the driver sets the first CPU port as the single port in this bit
> mask, which works fine regardless of whether the device tree defines port
> 5, 6 or 5+6 as CPU ports. This is because the logic coincides with DSA's
> logic of picking the first CPU port as the CPU port that all user ports are
> affine to, by default.
> 
> An upcoming change would like to influence DSA's selection of the default
> CPU port to no longer be the first one, and in that case, this logic needs
> adaptation.
> 
> Since there is no observed leakage or duplication of frames if all CPU
> ports are defined in this bit mask, simply include them all.

Nice and clear commit message, thanks.

> +	/* Add the CPU port to the CPU port bitmap for MT7531 and the switch on
> +	 * the MT7988 SoC. Trapped frames will be trapped to the CPU port that
> +	 * is affine to the inbound user port.

As a general rule, English doesn't like repetition in sentences, which
means that having "trapped" twice (or more times) makes the sentence
awkward.

"Trapped frames will be forwarded to the CPU port that is affine to the
inbound user port."

reads much better.

Apart from that...

Reviewed-by: Russell King (Oracle) <[email-masked]>

Thanks!

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