From: Rafael Beims rafael.beims@toradex.com
After U-Boot initializes PCIe with "pcie enum", Linux fails to detect an NVMe disk on some boot cycles with:
phy phy-32f00000.pcie-phy.0: phy poweron failed --> -110
Discussion with NXP identified that the iMX8MP PCIe PHY PLL may fail to lock when re-initialized without a reset cycle [1].
The issue reproduces on 7% of tested hardware platforms, with a 30-40% failure rate per affected device across boot cycles.
Insert a reset cycle in the power-on routine to ensure the PHY is initialized from a known state.
[1] https://community.nxp.com/t5/i-MX-Processors/iMX8MP-PCIe-initialization-in-U...
Signed-off-by: Rafael Beims rafael.beims@toradex.com Cc: stable@vger.kernel.org --- drivers/phy/freescale/phy-fsl-imx8m-pcie.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/phy/freescale/phy-fsl-imx8m-pcie.c b/drivers/phy/freescale/phy-fsl-imx8m-pcie.c index 68fcc8114d75..7f5600103a00 100644 --- a/drivers/phy/freescale/phy-fsl-imx8m-pcie.c +++ b/drivers/phy/freescale/phy-fsl-imx8m-pcie.c @@ -89,7 +89,8 @@ static int imx8_pcie_phy_power_on(struct phy *phy) writel(imx8_phy->tx_deemph_gen2, imx8_phy->base + PCIE_PHY_TRSV_REG6); break; - case IMX8MP: /* Do nothing. */ + case IMX8MP: + reset_control_assert(imx8_phy->reset); break; }