From: Matthias Kaehlcke <mka@chromium.org>
To: Rajendra Nayak <quic_rjendra@quicinc.com>
Cc: agross@kernel.org, andersson@kernel.org,
konrad.dybcio@somainline.org, robh+dt@kernel.org,
krzysztof.kozlowski+dt@linaro.org, linux-arm-msm@vger.kernel.org,
devicetree@vger.kernel.org, linux-kernel@vger.kernel.org,
sboyd@kernel.org, johan+linaro@kernel.org,
quic_kriskura@quicinc.com, dianders@chromium.org
Subject: Re: [Patch v2] arm64: dts: qcom: sc7280: Add required-opps for USB
Date: Fri, 16 Sep 2022 12:42:00 +0000 [thread overview]
Message-ID: <YyRvGDm2agpEI5zg@google.com> (raw)
In-Reply-To: <20220916103124.30581-1-quic_rjendra@quicinc.com>
On Fri, Sep 16, 2022 at 04:01:24PM +0530, Rajendra Nayak wrote:
> USB has a requirement to put a performance state vote on 'cx'
> while active. Use 'required-opps' to pass this information from
> device tree, and since all the GDSCs in GCC (including USB) are
> sub-domains of cx, we also add cx as a power-domain for GCC.
> Now when any of the consumers of the GDSCs (in this case USB)
> votes on a perforamance state, genpd framework can identify that
> the GDSC itself does not support a performance state and it
> then propogates the vote to the parent, which in this case is cx.
>
> This change would also mean that any GDSC in GCC thats left enabled
> during low power state (perhaps because its marked with a
> ALWAYS_ON flag) can prevent the system from entering low power
> since that would prevent cx from transitioning to low power.
> Ideally any consumers that would need to have their devices
> (partially) powered to support wakeups should look at making the
> resp. GDSCs transtion to a Retention (PWRSTS_RET) state instead
> of leaving them ALWAYS_ON.
>
> Signed-off-by: Rajendra Nayak <quic_rjendra@quicinc.com>
I suppose a similar patch is needed for sc7180?
prev parent reply other threads:[~2022-09-16 12:42 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-09-16 10:31 [Patch v2] arm64: dts: qcom: sc7280: Add required-opps for USB Rajendra Nayak
2022-09-16 12:42 ` Matthias Kaehlcke [this message]
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=YyRvGDm2agpEI5zg@google.com \
--to=mka@chromium.org \
--cc=agross@kernel.org \
--cc=andersson@kernel.org \
--cc=devicetree@vger.kernel.org \
--cc=dianders@chromium.org \
--cc=johan+linaro@kernel.org \
--cc=konrad.dybcio@somainline.org \
--cc=krzysztof.kozlowski+dt@linaro.org \
--cc=linux-arm-msm@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=quic_kriskura@quicinc.com \
--cc=quic_rjendra@quicinc.com \
--cc=robh+dt@kernel.org \
--cc=sboyd@kernel.org \
/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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.