Re: [PATCH 0/6] Additional regulator support for the Qualcomm SGMII SerDes PHY
From: Mohd Ayaan Anwar <mohd.anwar@oss.qualcomm.com>
Date: 2026-06-26 06:13:57
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On Mon, Jun 22, 2026 at 04:08:55PM +0200, Loic Poulain wrote:
Hi, On Mon, Nov 24, 2025 at 10:26 AM Mohd Ayaan Anwar [off-list ref] wrote:quoted
This patch series addresses a SerDes power-up failure observed on the QCS8300 Ride board using the phy-qcom-sgmii-eth driver. The issue occurs because the SerDes PHY requires both L5A and L4A regulators to be enabled during initialization. If either one of them is disabled, the status register does not reset, and the Ethernet interface fails to come up due to a timeout: [ 77.105651] qcom-dwmac-sgmii-phy 8909000.phy: QSERDES_COM_C_READY_STATUS timed-out [ 77.113447] qcom-ethqos 23040000.ethernet eth0: __stmmac_open: Serdes powerup failed Presumably, the issue is not seen on all users of this PHY because both regulators are often shared with other peripherals. However, the power rail schematics for boards using this SerDes PHY show that it is supplied by both L5A (1.2V) and L4A (0.9V) regulators. This series has been tested on the QCS8300 Ride board, and the reported issue was resolved. All Monaco and Lemans derivative boards require this new configuration as they use the same SerDes PHY. Signed-off-by: Mohd Ayaan Anwar <mohd.anwar@oss.qualcomm.com>This appears to be a real issue, but I haven’t seen a new version of the series or any response to the feedback so far. Could you please follow up on this?
I will shortly send out a v2. I got access to more details about the hardware, and it has two dedicated regulators which need to be enabled. The same requirements are there on all Lemans/Monaco-based boards. Ayaan -- linux-phy mailing list linux-phy@lists.infradead.org https://lists.infradead.org/mailman/listinfo/linux-phy