]> git.ipfire.org Git - thirdparty/kernel/linux.git/commitdiff
arm64: dts: qcom: qcs615: Set LDO12A regulator to HPM to avoid boot hang
authorZiyue Zhang <ziyue.zhang@oss.qualcomm.com>
Thu, 17 Jul 2025 07:27:46 +0000 (15:27 +0800)
committerBjorn Andersson <andersson@kernel.org>
Mon, 11 Aug 2025 21:47:35 +0000 (16:47 -0500)
On certain platforms (e.g., QCS615), consumers of LDO12A—such as PCIe,
UFS, and eMMC—may draw more than 10mA of current during boot. This can
exceed the regulator's limit in Low Power Mode (LPM), triggering current
limit protection and causing the system to hang.

To address this, there are two possible approaches:
a) Set the regulator's initial mode to High Performance Mode (HPM) in
   the device tree.
b) Keep the default LPM setting and have each consumer driver explicitly
   set its current load.

Since some regulators are shared among multiple consumers, and setting
the current must be coordinated across all of them, we will initially
adopt option a by setting the regulator to HPM. We can later migrate to
option b when the timing is appropriate and all consumer drivers are
ready.

Signed-off-by: Ziyue Zhang <ziyue.zhang@oss.qualcomm.com>
Signed-off-by: Tingguo Cheng <quic_tingguoc@quicinc.com>
Link: https://lore.kernel.org/r/20250717072746.987298-1-quic_ziyuzhan@quicinc.com
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
arch/arm64/boot/dts/qcom/qcs615-ride.dts

index 36978fdfe3dd4be8b46df97ad596eb22730ea59b..59582d3dc4c49828ef4a0d22a1cbaba715c7ce8c 100644 (file)
                        regulator-name = "vreg_l12a";
                        regulator-min-microvolt = <1800000>;
                        regulator-max-microvolt = <1890000>;
-                       regulator-initial-mode = <RPMH_REGULATOR_MODE_LPM>;
-                       regulator-allow-set-load;
-                       regulator-allowed-modes = <RPMH_REGULATOR_MODE_LPM
-                                                  RPMH_REGULATOR_MODE_HPM>;
+                       regulator-initial-mode = <RPMH_REGULATOR_MODE_HPM>;
                };
 
                vreg_l13a: ldo13 {