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SubjectRe: [PATCH] spi: spi-geni-qcom: Don't wait to start 1st transfer if transmitting
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On 9/12/2020 11:47 PM, Douglas Anderson wrote:
> If we're sending bytes over SPI, we know the FIFO is empty at the
> start of the transfer. There's no reason to wait for the interrupt
> telling us to start--we can just start right away. Then if we
> transmit everything in one swell foop we don't even need to bother
> listening for TX interrupts.
>
> In a test of "flashrom -p ec -r /tmp/foo.bin" interrupts were reduced
> from ~30560 to ~29730, about a 3% savings.
>
> This patch looks bigger than it is because I moved a few functions
> rather than adding a forward declaration. The only actual change to
> geni_spi_handle_tx() was to make it return a bool indicating if there
> is more to tx.
Reviewed-by: Akash Asthana <akashast@codeaurora.org>
> Signed-off-by: Douglas Anderson<dianders@chromium.org>

--
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,\na Linux Foundation Collaborative Project

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