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From:   Martin Kepplinger <martin.kepplinger@puri.sm>
To:     robh@kernel.org, shawnguo@kernel.org, festevam@gmail.com
Cc:     kernel@pengutronix.de, linux-imx@nxp.com, krzk@kernel.org,
        kernel@puri.sm, devicetree@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org,
        Martin Kepplinger <martin.kepplinger@puri.sm>
Subject: [PATCH 4/4] arm64: dts: imx8mq-librem5-r3: workaround i2c1 issue with 1GHz cpu voltage
Date:   Fri, 18 Dec 2020 11:31:31 +0100
Message-Id: <20201218103131.22013-5-martin.kepplinger@puri.sm>
In-Reply-To: <20201218103131.22013-1-martin.kepplinger@puri.sm>
References: <20201218103131.22013-1-martin.kepplinger@puri.sm>
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This is a workaround for a hardware bug in the r3 revision that basically would
stop the system due to traffic on the i2c1 bus. A cpu voltage change would
trigger such traffic and that's what is avoided in order to work around it.

Signed-off-by: Martin Kepplinger <martin.kepplinger@puri.sm>
---
 arch/arm64/boot/dts/freescale/imx8mq-librem5-r3.dts | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/arch/arm64/boot/dts/freescale/imx8mq-librem5-r3.dts b/arch/arm64/boot/dts/freescale/imx8mq-librem5-r3.dts
index 6704ea2c72a3..0d38327043f8 100644
--- a/arch/arm64/boot/dts/freescale/imx8mq-librem5-r3.dts
+++ b/arch/arm64/boot/dts/freescale/imx8mq-librem5-r3.dts
@@ -10,6 +10,12 @@
 	compatible = "purism,librem5r3", "purism,librem5", "fsl,imx8mq";
 };
 
+&a53_opp_table {
+	opp-1000000000 {
+		opp-microvolt = <1000000>;
+	};
+};
+
 &accel_gyro {
 	mount-matrix =  "1",  "0",  "0",
 			"0",  "1",  "0",
-- 
2.20.1