From: Stefan Eichenberger <stefan.eichenberger@xxxxxxxxxxx>
Ensure the PHY reset and perst is asserted during power-off to
guarantee it is in a reset state upon repeated power-on calls. This
resolves an issue where the PHY may not properly initialize during
subsequent power-on cycles. Power-on will deassert the reset at the
appropriate time after tuning the PHY parameters.
During suspend/resume cycles, we observed that the PHY PLL failed to
lock during resume when the CPU temperature increased from 65C to 75C.
The observed errors were:
phy phy-32f00000.pcie-phy.3: phy poweron failed --> -110
imx6q-pcie 33800000.pcie: waiting for PHY ready timeout!
imx6q-pcie 33800000.pcie: PM: dpm_run_callback(): genpd_resume_noirq+0x0/0x80 returns -110
imx6q-pcie 33800000.pcie: PM: failed to resume noirq: error -110
This resulted in a complete CPU freeze, which is resolved by ensuring
the PHY is in reset during power-on, thus preventing PHY PLL failures.
Cc: stable@xxxxxxxxxxxxxxx
Fixes: 1aa97b002258 ("phy: freescale: pcie: Initialize the imx8 pcie standalone phy driver")
Signed-off-by: Stefan Eichenberger <stefan.eichenberger@xxxxxxxxxxx>
---
drivers/phy/freescale/phy-fsl-imx8m-pcie.c | 12 ++++++++++++
1 file changed, 12 insertions(+)
diff --git a/drivers/phy/freescale/phy-fsl-imx8m-pcie.c b/drivers/phy/freescale/phy-fsl-imx8m-pcie.c
index 00f957a42d9dc..36bef416618de 100644
--- a/drivers/phy/freescale/phy-fsl-imx8m-pcie.c
+++ b/drivers/phy/freescale/phy-fsl-imx8m-pcie.c
@@ -158,6 +158,17 @@ static int imx8_pcie_phy_power_on(struct phy *phy)
return ret;
}
+static int imx8_pcie_phy_power_off(struct phy *phy)
+{
+ struct imx8_pcie_phy *imx8_phy = phy_get_drvdata(phy);
+
+ reset_control_assert(imx8_phy->reset);
+ if (imx8_phy->perst)
+ reset_control_assert(imx8_phy->perst);
+
+ return 0;
+}
+
static int imx8_pcie_phy_init(struct phy *phy)
{
struct imx8_pcie_phy *imx8_phy = phy_get_drvdata(phy);
@@ -178,6 +189,7 @@ static const struct phy_ops imx8_pcie_phy_ops = {
.init = imx8_pcie_phy_init,
.exit = imx8_pcie_phy_exit,
.power_on = imx8_pcie_phy_power_on,
+ .power_off = imx8_pcie_phy_power_off,
.owner = THIS_MODULE,
};
--
2.45.2
