From: Chanwoo Choi <cw00.choi@samsung.com>
To: Dmitry Osipenko <digetx@gmail.com>,
Thierry Reding <thierry.reding@gmail.com>,
MyungJoo Ham <myungjoo.ham@samsung.com>,
Kyungmin Park <kyungmin.park@samsung.com>,
Jonathan Hunter <jonathanh@nvidia.com>,
Tomeu Vizoso <tomeu.vizoso@collabora.com>,
Peter Geis <pgwipeout@gmail.com>
Cc: linux-pm@vger.kernel.org, linux-tegra@vger.kernel.org,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH v7 18/19] PM / devfreq: tegra30: Tune up MCCPU boost-down coefficient
Date: Fri, 1 Nov 2019 16:45:40 +0900 [thread overview]
Message-ID: <99a90972-2170-ebcb-7bff-cd9ba8b0b0d1@samsung.com> (raw)
In-Reply-To: <20191029220019.26773-19-digetx@gmail.com>
On 19. 10. 30. 오전 7:00, Dmitry Osipenko wrote:
> MCCPU boosts up very aggressively by 800% and boosts down very mildly by
> 10%. This doesn't work well when system is idling because the very slow
> de-boosting results in lots of consecutive-down interrupts, in result
> memory stays clocked high and CPU doesn't enter deepest idling state
> instead of keeping memory at lowest freq and having CPU cluster turned
> off. A more faster de-boosting fixes the case of idling system and doesn't
> affect the case of an active system.
>
> Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
> ---
> drivers/devfreq/tegra30-devfreq.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/devfreq/tegra30-devfreq.c b/drivers/devfreq/tegra30-devfreq.c
> index d0dd42856e5b..9a21a29198ee 100644
> --- a/drivers/devfreq/tegra30-devfreq.c
> +++ b/drivers/devfreq/tegra30-devfreq.c
> @@ -123,7 +123,7 @@ static const struct tegra_devfreq_device_config actmon_device_configs[] = {
> .offset = 0x200,
> .irq_mask = 1 << 25,
> .boost_up_coeff = 800,
> - .boost_down_coeff = 90,
> + .boost_down_coeff = 40,
> .boost_up_threshold = 27,
> .boost_down_threshold = 10,
> .avg_dependency_threshold = 50000,
>
Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
IMO, I think that it is not good to change the threshold value
on device driver directly when some requirement happen.
Instead, better to get the threshold value from device-tree file.
--
Best Regards,
Chanwoo Choi
Samsung Electronics
next prev parent reply other threads:[~2019-11-01 7:40 UTC|newest]
Thread overview: 34+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-10-29 22:00 [PATCH v7 00/19] More improvements for Tegra30 devfreq driver Dmitry Osipenko
2019-10-29 22:00 ` [PATCH v7 01/19] PM / devfreq: tegra30: Change irq type to unsigned int Dmitry Osipenko
2019-10-29 22:00 ` [PATCH v7 02/19] PM / devfreq: tegra30: Keep interrupt disabled while governor is stopped Dmitry Osipenko
2019-10-29 22:00 ` [PATCH v7 03/19] PM / devfreq: tegra30: Handle possible round-rate error Dmitry Osipenko
2019-10-29 22:00 ` [PATCH v7 04/19] PM / devfreq: tegra30: Drop write-barrier Dmitry Osipenko
2019-10-29 22:00 ` [PATCH v7 05/19] PM / devfreq: tegra30: Fix integer overflow on CPU's freq max out Dmitry Osipenko
2019-10-29 22:00 ` [PATCH v7 06/19] PM / devfreq: tegra30: Use kHz units uniformly in the code Dmitry Osipenko
2019-10-31 4:44 ` Chanwoo Choi
2019-10-31 23:08 ` Dmitry Osipenko
2019-10-29 22:00 ` [PATCH v7 07/19] PM / devfreq: tegra30: Use CPUFreq notifier Dmitry Osipenko
2019-10-29 22:00 ` [PATCH v7 08/19] PM / devfreq: tegra30: Move clk-notifier's registration to governor's start Dmitry Osipenko
2019-10-29 22:00 ` [PATCH v7 09/19] PM / devfreq: tegra30: Reset boosting on startup Dmitry Osipenko
2019-10-29 22:00 ` [PATCH v7 10/19] PM / devfreq: tegra30: Don't enable consecutive-down interrupt " Dmitry Osipenko
2019-10-29 22:00 ` [PATCH v7 11/19] PM / devfreq: tegra30: Constify structs Dmitry Osipenko
2019-10-29 22:00 ` [PATCH v7 12/19] PM / devfreq: tegra30: Include appropriate header Dmitry Osipenko
2019-10-29 22:00 ` [PATCH v7 13/19] PM / devfreq: tegra30: Increase sampling period to 16ms Dmitry Osipenko
2019-11-01 21:53 ` Michał Mirosław
2019-10-29 22:00 ` [PATCH v7 14/19] PM / devfreq: tegra30: Don't enable already enabled consecutive interrupts Dmitry Osipenko
2019-11-01 7:00 ` Chanwoo Choi
2019-10-29 22:00 ` [PATCH v7 15/19] PM / devfreq: tegra30: Disable consecutive interrupts when appropriate Dmitry Osipenko
2019-11-01 7:01 ` Chanwoo Choi
2019-10-29 22:00 ` [PATCH v7 16/19] PM / devfreq: Add new interrupt_driven flag for governors Dmitry Osipenko
2019-11-01 7:32 ` Chanwoo Choi
2019-11-01 13:56 ` Dmitry Osipenko
2019-10-29 22:00 ` [PATCH v7 17/19] PM / devfreq: tegra30: Support variable polling interval Dmitry Osipenko
2019-11-01 7:41 ` Chanwoo Choi
2019-11-01 13:55 ` Dmitry Osipenko
2019-11-01 21:58 ` Michał Mirosław
2019-11-01 22:23 ` Dmitry Osipenko
2019-11-03 15:25 ` Dmitry Osipenko
2019-10-29 22:00 ` [PATCH v7 18/19] PM / devfreq: tegra30: Tune up MCCPU boost-down coefficient Dmitry Osipenko
2019-11-01 7:45 ` Chanwoo Choi [this message]
2019-11-01 14:14 ` Dmitry Osipenko
2019-10-29 22:00 ` [PATCH v7 19/19] PM / devfreq: tegra20/30: Add Dmitry as a maintainer Dmitry Osipenko
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=99a90972-2170-ebcb-7bff-cd9ba8b0b0d1@samsung.com \
--to=cw00.choi@samsung.com \
--cc=digetx@gmail.com \
--cc=jonathanh@nvidia.com \
--cc=kyungmin.park@samsung.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-pm@vger.kernel.org \
--cc=linux-tegra@vger.kernel.org \
--cc=myungjoo.ham@samsung.com \
--cc=pgwipeout@gmail.com \
--cc=thierry.reding@gmail.com \
--cc=tomeu.vizoso@collabora.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).