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Date:   Wed, 16 Feb 2022 00:49:50 +0300
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Subject: Re: [PATCH v2] PM: domains: Prevent power off for parent unless child
 is in deepest state
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To:     Ulf Hansson <ulf.hansson@linaro.org>,
        "Rafael J . Wysocki" <rafael@kernel.org>, linux-pm@vger.kernel.org
Cc:     Kevin Hilman <khilman@kernel.org>,
        Alexandre Torgue <alexandre.torgue@foss.st.com>,
        Geert Uytterhoeven <geert+renesas@glider.be>,
        Rajendra Nayak <rnayak@codeaurora.org>,
        Dong Aisheng <aisheng.dong@nxp.com>,
        linux-kernel@vger.kernel.org
References: <20220204101657.233723-1-ulf.hansson@linaro.org>
From:   Dmitry Osipenko <digetx@gmail.com>
In-Reply-To: <20220204101657.233723-1-ulf.hansson@linaro.org>
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04.02.2022 13:16, Ulf Hansson пишет:
> A PM domain managed by genpd may support multiple idlestates. During
> genpd_power_off() a genpd governor may be asked to select one of the
> idlestates based upon the dev PM QoS constraints, for example.
> 
> However, there is a problem with the behaviour around this in genpd. More
> precisely, a parent-domain is allowed to be powered off, no matter of what
> idlestate that has been selected for the child-domain.
> 
> So far, we have not received any reports about errors from the current
> behaviour. However, there is an STMicro platform that is being worked on,
> which can't cope with this.

Could you please provide some technical info about why STMicro platform
can't cope with that?