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From: Akash Asthana <akashast@codeaurora.org>
To: Douglas Anderson <dianders@chromium.org>,
	Mark Brown <broonie@kernel.org>
Cc: swboyd@chromium.org, Andy Gross <agross@kernel.org>,
	Bjorn Andersson <bjorn.andersson@linaro.org>,
	linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org,
	linux-spi@vger.kernel.org
Subject: Re: [PATCH] spi: spi-geni-qcom: Don't wait to start 1st transfer if transmitting
Date: Mon, 14 Sep 2020 18:39:25 +0530	[thread overview]
Message-ID: <838a6074-73e6-a48b-2684-5ea2ebff443a@codeaurora.org> (raw)
In-Reply-To: <20200912111716.1.Ied5e843fad0d6b733a1fb8bcfb364dd2fa889eb3@changeid>


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


  parent reply	other threads:[~2020-09-14 13:21 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-09-12 18:17 [PATCH] spi: spi-geni-qcom: Don't wait to start 1st transfer if transmitting Douglas Anderson
2020-09-12 23:09 ` Bjorn Andersson
2020-09-14 13:09 ` Akash Asthana [this message]
2020-09-14 14:52 ` Mark Brown

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