[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-Id: <20250818-imx9-dts-v2-8-8ba787fb5280@nxp.com>
Date: Mon, 18 Aug 2025 09:25:38 +0800
From: Peng Fan <peng.fan@....com>
To: Rob Herring <robh@...nel.org>, Krzysztof Kozlowski <krzk+dt@...nel.org>,
Conor Dooley <conor+dt@...nel.org>, Shawn Guo <shawnguo@...nel.org>,
Sascha Hauer <s.hauer@...gutronix.de>,
Pengutronix Kernel Team <kernel@...gutronix.de>,
Fabio Estevam <festevam@...il.com>, Frank Li <Frank.Li@....com>
Cc: devicetree@...r.kernel.org, imx@...ts.linux.dev,
linux-arm-kernel@...ts.infradead.org, linux-kernel@...r.kernel.org,
Peng Fan <peng.fan@....com>, Richard Zhu <hongxing.zhu@....com>
Subject: [PATCH v2 08/11] arm64: dts: imx95-19x19-evk: Add Tsettle delay in
m2 regulator
From: Richard Zhu <hongxing.zhu@....com>
M.2 device only can be enabled after all Power Rails reach their minimum
operating voltage (PCI Express M.2 Specification r5.1 3.1.4 Power-up
Timing). Set a delay equal to the max value of Tsettle in m2 regulator.
Signed-off-by: Richard Zhu <hongxing.zhu@....com>
Reviewed-by: Frank Li <Frank.Li@....com>
Signed-off-by: Peng Fan <peng.fan@....com>
---
arch/arm64/boot/dts/freescale/imx95-19x19-evk.dts | 7 +++++++
1 file changed, 7 insertions(+)
diff --git a/arch/arm64/boot/dts/freescale/imx95-19x19-evk.dts b/arch/arm64/boot/dts/freescale/imx95-19x19-evk.dts
index 39815b21d235d2f8cfa49720d3be49d056ea039a..6d2f09404bdb8bee62532f1e02f59bd5a899833e 100644
--- a/arch/arm64/boot/dts/freescale/imx95-19x19-evk.dts
+++ b/arch/arm64/boot/dts/freescale/imx95-19x19-evk.dts
@@ -136,6 +136,13 @@ reg_m2_pwr: regulator-m2-pwr {
regulator-max-microvolt = <3300000>;
gpio = <&i2c7_pcal6524 20 GPIO_ACTIVE_HIGH>;
enable-active-high;
+ /*
+ * M.2 device only can be enabled(W_DISABLE1#) after all Power
+ * Rails reach their minimum operating voltage (PCI Express M.2
+ * Specification r5.1 3.1.4 Power-up Timing).
+ * Set a delay equal to the max value of Tsettle here.
+ */
+ startup-delay-us = <5000>;
};
reg_pcie0: regulator-pcie {
--
2.37.1
Powered by blists - more mailing lists