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Commit0cc22f5a86("phy: qcom: qmp-pcie: Add PHY register retention support") added support for using the "no_csr" reset to skip configuration of the PHY if the init sequence was already applied by the boot firmware. The expectation is that the PHY is only turned on/off by using the "no_csr" reset, instead of powering it down and re-programming it after a full reset. The boot firmware on X1E does not fully conform to this expectation: If the PCIe3 link fails to come up (e.g. because no PCIe card is inserted), the firmware powers down the PHY using the QPHY_PCS_POWER_DOWN_CONTROL register. The QPHY_START_CTRL register is kept as-is, so the driver assumes the PHY is already initialized and skips the configuration/power up sequence. The PHY won't come up again without clearing the QPHY_PCS_POWER_DOWN_CONTROL, so eventually initialization fails: qcom-qmp-pcie-phy 1be0000.phy: phy initialization timed-out phy phy-1be0000.phy.0: phy poweron failed --> -110 qcom-pcie 1bd0000.pcie: cannot initialize host qcom-pcie 1bd0000.pcie: probe with driver qcom-pcie failed with error -110 This can be reliably reproduced on the X1E CRD, QCP and Devkit when no card is inserted for PCIe3. Fix this by checking the QPHY_PCS_POWER_DOWN_CONTROL register in addition to QPHY_START_CTRL. If the PHY is powered down with the register, it doesn't conform to the expectations for using the "no_csr" reset, so we fully re-initialize with the normal reset sequence. Also check the register more carefully to ensure all of the bits we expect are actually set. A simple !!(readl()) is not enough, because the PHY might be only partially set up with some of the expected bits set. Cc: stable@vger.kernel.org Fixes:0cc22f5a86("phy: qcom: qmp-pcie: Add PHY register retention support") Signed-off-by: Stephan Gerhold <stephan.gerhold@linaro.org> Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com> Link: https://lore.kernel.org/r/20250821-phy-qcom-qmp-pcie-nocsr-fix-v3-1-4898db0cc07c@linaro.org Signed-off-by: Vinod Koul <vkoul@kernel.org>