Re: [PATCH] soc: qcom-geni-se: Don't use relaxed writes when writing commands

[Akash Asthana]

On 7/23/2020 3:31 AM, Douglas Anderson wrote:
> Writing the command is the final step in kicking off a transfer.
> Let's use writel() to ensure that any other memory accesses are done
> before the command kicks off.  It's expected that this is mostly
> relevant if we're in DMA mode but since it doesn't appear to regress
> performance in a measurable way [1] even in PIO mode and it's easier
> to reason about then let's just always use it.
>
> NOTE: this patch came about due to code inspection.  No actual
> problems were observed that this patch fixes.
>
> [1] Tested by timing "flashrom -p ec" on a Chromebook which stresses
> GENI SPI a lot.
>
> Suggested-by: Stephen Boyd <swboyd@xxxxxxxxxxxx>
> Signed-off-by: Douglas Anderson <dianders@xxxxxxxxxxxx>
> ---
Reviewed-by: Akash Asthana <akashast@xxxxxxxxxxxxxx>

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