Re: [PATCH v2 1/2] PM / Domains: Add GENPD_FLAG_NO_SUSPEND/RESUME flags

From: Ulf Hansson <ulf.hansson@linaro.org>
To: Sibi Sankar <sibis@codeaurora.org>
Cc: Stephen Boyd <swboyd@chromium.org>,
	"Rafael J. Wysocki" <rafael@kernel.org>,
	Bjorn Andersson <bjorn.andersson@linaro.org>,
	Kevin Hilman <khilman@kernel.org>,
	"Rafael J. Wysocki" <rjw@rjwysocki.net>,
	Andy Gross <agross@kernel.org>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	linux-arm-msm <linux-arm-msm@vger.kernel.org>,
	Linux PM <linux-pm@vger.kernel.org>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Pavel Machek <pavel@ucw.cz>, Len Brown <len.brown@intel.com>,
	"Nayak, Rajendra" <rnayak@codeaurora.org>,
	Doug Anderson <dianders@chromium.org>,
	Matthias Kaehlcke <mka@chromium.org>
Subject: Re: [PATCH v2 1/2] PM / Domains: Add GENPD_FLAG_NO_SUSPEND/RESUME flags
Date: Tue, 22 Sep 2020 09:31:21 +0200	[thread overview]
Message-ID: <CAPDyKFrOPPkkbuPUDS_+mnVS=rsoCBm0VCD1Qqz_3rChPcp+4Q@mail.gmail.com> (raw)
In-Reply-To: <14eb0558c8ff820280bb7354cfe33326@codeaurora.org>

On Tue, 22 Sep 2020 at 06:51, Sibi Sankar <sibis@codeaurora.org> wrote:
>
> On 2020-09-22 01:26, Stephen Boyd wrote:
> > Quoting Rafael J. Wysocki (2020-09-21 09:18:17)
> >> On Fri, Aug 21, 2020 at 10:49 PM Sibi Sankar <sibis@codeaurora.org>
> >> wrote:
> >> >
> >> > Add GENPD_FLAG_NO_SUSPEND/RESUME flags to instruct genpd to keep the
> >> > status of the PM domain unaltered during suspend/resume respectively.
> >> > The flags are aimed at power domains coupled to co-processors which
> >> > enter low-power modes independent to that of the application processor.
> >> >
> >> > Specifically the flags are to be used by the power domains exposed
> >> > by the AOSS QMP driver linked to modem, adsp, cdsp remoteprocs. These
> >> > power domains are used to notify the Always on Subsystem (AOSS) that
> >> > a particular co-processor is up. AOSS uses this information to wait
> >> > for the co-processors to suspend before starting its sleep sequence.
> >> > The application processor powers off these power domains only if the
> >> > co-processor has crashed or powered off and remains unaltered during
> >> > system suspend/resume.
> >> >
> >> > Signed-off-by: Sibi Sankar <sibis@codeaurora.org>
> >>
> >> Applied with the Ulf's R-by along with the [2/2] as 5.10 material,
> >> thanks!
> >>
> >
> > There was a bunch of discussion on this patch series and I thought the
> > consensus was to not apply these patches and instead implement a custom
> > qcom specific API that does this instead.
>
> https://lore.kernel.org/lkml/20200913034603.GV3715@yoga/
>
> The power domains which were targeted
> to use the flags will be replaced by
> custom qcom specific API. So let's not
> pick up the patch series.

I am fine with either option. However, please keep me posted, as I am
a bit curious how this will look like in the qcom specific drivers.

Kind regards
Uffe