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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 v2 4/4] arm64: dts: imx8mq-librem5-r3: workaround i2c1 issue with 1GHz cpu voltage
Date: Tue, 22 Dec 2020 16:13:47 +0100	[thread overview]
Message-ID: <20201222151347.7886-5-martin.kepplinger@puri.sm> (raw)
In-Reply-To: <20201222151347.7886-1-martin.kepplinger@puri.sm>

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


WARNING: multiple messages have this Message-ID (diff)
From: Martin Kepplinger <martin.kepplinger@puri.sm>
To: robh@kernel.org, shawnguo@kernel.org, festevam@gmail.com
Cc: devicetree@vger.kernel.org, kernel@puri.sm,
	Martin Kepplinger <martin.kepplinger@puri.sm>,
	linux-kernel@vger.kernel.org, krzk@kernel.org, linux-imx@nxp.com,
	kernel@pengutronix.de, linux-arm-kernel@lists.infradead.org
Subject: [PATCH v2 4/4] arm64: dts: imx8mq-librem5-r3: workaround i2c1 issue with 1GHz cpu voltage
Date: Tue, 22 Dec 2020 16:13:47 +0100	[thread overview]
Message-ID: <20201222151347.7886-5-martin.kepplinger@puri.sm> (raw)
In-Reply-To: <20201222151347.7886-1-martin.kepplinger@puri.sm>

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


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  parent reply	other threads:[~2020-12-22 15:15 UTC|newest]

Thread overview: 18+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-12-22 15:13 [PATCH v2 0/4] small Librem 5 phone dts updates Martin Kepplinger
2020-12-22 15:13 ` Martin Kepplinger
2020-12-22 15:13 ` [PATCH v2 1/4] arm64: dts: imx8mq-librem5: add vin-supply to VDD_1V8 Martin Kepplinger
2020-12-22 15:13   ` Martin Kepplinger
2020-12-22 15:13 ` [PATCH v2 2/4] arm64: dts: imx8mq-librem5: add pinctrl for the touchscreen description Martin Kepplinger
2020-12-22 15:13   ` Martin Kepplinger
2020-12-23  9:58   ` Krzysztof Kozlowski
2020-12-23  9:58     ` Krzysztof Kozlowski
2021-01-11  0:29   ` Shawn Guo
2021-01-11  0:29     ` Shawn Guo
2021-01-11  8:24     ` Martin Kepplinger
2021-01-11  8:24       ` Martin Kepplinger
2020-12-22 15:13 ` [PATCH v2 3/4] arm64: dts: imx8mq-librem5: Move usdhc clocks assignment to board DT Martin Kepplinger
2020-12-22 15:13   ` Martin Kepplinger
2020-12-23  9:58   ` Krzysztof Kozlowski
2020-12-23  9:58     ` Krzysztof Kozlowski
2020-12-22 15:13 ` Martin Kepplinger [this message]
2020-12-22 15:13   ` [PATCH v2 4/4] arm64: dts: imx8mq-librem5-r3: workaround i2c1 issue with 1GHz cpu voltage Martin Kepplinger

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