[PATCH 0/2] phy: qcom: qmp-pcie: Add PCIe PHY no_csr reset support

From: Wenbin Yao
Date: Tue Jan 21 2025 - 04:43:09 EST


The series aims to skip phy register programming and drive PCIe PHY with
register setting programmed in bootloader by simply toggling no_csr reset,
which once togglled, PHY hardware will be reset while PHY registers are
retained.

First, determine whether PHY setting can be skipped by checking
QPHY_START_CTRL register and the existence of nocsr reset. If it is
programmed and no_csr reset is supported, do no_csr reset and skip BCR
reset which will reset entire PHY.

This series also remove has_nocsr_reset flag in qmp_phy_cfg structure and
decide whether the PHY supports nocsr reset by checking the existence of
nocsr reset in device tree.

The series are tested on X1E80100-QCP and HDK8550.

Wenbin Yao (2):
phy: qcom: pcie: Determine has_nocsr_reset dynamically
phy: qcom: qmp-pcie: Add PHY register retention support

drivers/phy/qualcomm/phy-qcom-qmp-pcie.c | 109 ++++++++++++++---------
1 file changed, 65 insertions(+), 44 deletions(-)


base-commit: bcf2acd8f64b0a5783deeeb5fd70c6163ec5acd7
--
2.34.1