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Message-ID: <898fd5e0-2073-3689-89b6-2c5071773786@kontron.de>
Date:   Wed, 15 Sep 2021 14:09:06 +0200
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Subject: Re: [PATCH] arm64: dts: imx8mm-kontron-n801x-som: do not allow to
 switch off buck2
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To:     Michael Walle <michael@walle.cc>,
        Heiko Thiery <heiko.thiery@gmail.com>
Cc:     devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        linux-kernel@vger.kernel.org,
        Krzysztof Kozlowski <krzk@kernel.org>,
        Joakim Zhang <qiangqing.zhang@nxp.com>,
        Shengjiu Wang <shengjiu.wang@nxp.com>,
        Rob Herring <robh+dt@kernel.org>,
        Shawn Guo <shawnguo@kernel.org>,
        Sascha Hauer <s.hauer@pengutronix.de>,
        Pengutronix Kernel Team <kernel@pengutronix.de>,
        Fabio Estevam <festevam@gmail.com>,
        NXP Linux Team <linux-imx@nxp.com>
References: <20210915120325.20248-1-heiko.thiery@gmail.com>
 <7e7ee4244ababc0a46e0875222c7e37d@walle.cc>
From:   Frieder Schrempf <frieder.schrempf@kontron.de>
In-Reply-To: <7e7ee4244ababc0a46e0875222c7e37d@walle.cc>
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On 15.09.21 14:05, Michael Walle wrote:
> Am 2021-09-15 14:03, schrieb Heiko Thiery:
>> The buck2 output of the PMIC is the VDD core voltage of the cpu.
>> Switching off this will poweroff the CPU. Add the 'regulator-always-on'
>> property to avoid this.
> 
> Mh, have this ever worked? Is there a commit which introduced a regression?

Yes, this did work before, even without 'regulator-always-on'. I
currently don't understand why this is needed. The regulator is
referenced in the CPU nodes as 'cpu-supply'. This should be enough to
not disable it as long as the CPU is up.