Re: [PATCH 1/3] spi: spi-geni-qcom: Use the FIFO even more

[Akash Asthana]

On 9/13/2020 2:37 AM, Douglas Anderson wrote:
> In commit 902481a78ee4 ("spi: spi-geni-qcom: Actually use our FIFO") I
> explained that the maximum size we could program the FIFO was
> "mas->tx_fifo_depth - 3" but that I chose "mas->tx_fifo_depth()"
> because I was worried about decreased bandwidth.
>
> Since that time:
> * All the interconnect patches have landed, making things run at the
>    proper speed.
> * I've done more measurements.
>
> This lets me confirm that there's really no downside of using the FIFO
> more.  Specifically I did "flashrom -p ec -r /tmp/foo.bin" on a
> Chromebook and averaged over several runs.
>
> Before: It took 6.66 seconds and 59669 interrupts fired.
> After:  It took 6.66 seconds and 47992 interrupts fired.

Reviewed-by: Akash Asthana <akashast@xxxxxxxxxxxxxx>

> Signed-off-by: Douglas Anderson <dianders@xxxxxxxxxxxx>
> ---
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