[PATCH net] net: stmmac: propagate PTP init failures in __stmmac_open() and stmmac_resume()
flat view
COLD42d
From: Lorenzo Bianconi <hidden>
Date: 2026-09-04 09:04:49
Also in:
linux-arm-kernel
Subsystem:
networking drivers, stmmac ethernet driver, the rest · Maintainers:
Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Maxime Chevallier, Linus Torvalds
stmmac_setup_ptp() returns void and swallows both PTP setup errors:
the PTP reference clock enable and stmmac_init_timestamping()
failures are logged but never propagated. When they fail, the MAC
system time counter is left in its post-reset, non-running state,
while the driver keeps operating as if timestamping were up.
This matters for TAPRIO/EST qdisc offloading, which derives the EST
base time from the hardware timestamp counter: arming the gate list
against a non-advancing time base would leave the schedule permanently
stuck. Make stmmac_setup_ptp() return an error code.
Fixes: 92ba6888510c ("stmmac: add the support for PTP hw clock driver")
Fixes: 0ad2be79f254 ("net: stmmac: Balance PTP reference clock enable/disable")
Signed-off-by: Lorenzo Bianconi <redacted>
---
drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 66 ++++++++++++++++-------
1 file changed, 48 insertions(+), 18 deletions(-)
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index 24656b35350b..d33c82bd3ee4 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c@@ -885,6 +885,11 @@ static int stmmac_init_tstamp_counter(struct stmmac_priv *priv, return 0; } +static bool stmmac_check_timestamp_cap(struct stmmac_priv *priv) +{ + return priv->dma_cap.time_stamp || priv->dma_cap.atime_stamp; +} + /** * stmmac_init_timestamping - initialise timestamping * @priv: driver private structure
@@ -900,11 +905,6 @@ static int stmmac_init_timestamping(struct stmmac_priv *priv) if (priv->plat->ptp_clk_freq_config) priv->plat->ptp_clk_freq_config(priv); - if (!(priv->dma_cap.time_stamp || priv->dma_cap.atime_stamp)) { - netdev_info(priv->dev, "PTP not supported by HW\n"); - return -EOPNOTSUPP; - } - ret = stmmac_init_tstamp_counter(priv, STMMAC_HWTS_ACTIVE | PTP_TCR_TSCFUPDT); if (ret) {
@@ -937,22 +937,39 @@ static int stmmac_init_timestamping(struct stmmac_priv *priv) return 0; } -static void stmmac_setup_ptp(struct stmmac_priv *priv) +static int stmmac_setup_ptp(struct stmmac_priv *priv) { int ret; + if (!stmmac_check_timestamp_cap(priv)) { + netdev_info(priv->dev, "PTP not supported by HW\n"); + return 0; + } + ret = clk_prepare_enable(priv->plat->clk_ptp_ref); - if (ret < 0) + if (ret < 0) { netdev_warn(priv->dev, "failed to enable PTP reference clock: %pe\n", ERR_PTR(ret)); + return ret; + } + + ret = stmmac_init_timestamping(priv); + if (ret) { + clk_disable_unprepare(priv->plat->clk_ptp_ref); + return ret; + } - if (stmmac_init_timestamping(priv) == 0) - stmmac_ptp_register(priv); + stmmac_ptp_register(priv); + + return 0; } static void stmmac_release_ptp(struct stmmac_priv *priv) { + if (!stmmac_check_timestamp_cap(priv)) + return; + stmmac_ptp_unregister(priv); clk_disable_unprepare(priv->plat->clk_ptp_ref); }
@@ -4161,10 +4178,12 @@ static int __stmmac_open(struct net_device *dev, ret = stmmac_hw_setup(dev); if (ret < 0) { netdev_err(priv->dev, "%s: Hw setup failed\n", __func__); - goto init_error; + return ret; } - stmmac_setup_ptp(priv); + ret = stmmac_setup_ptp(priv); + if (ret) + goto ptp_error; stmmac_init_coalesce(priv);
@@ -4187,9 +4206,10 @@ static int __stmmac_open(struct net_device *dev, for (chan = 0; chan < priv->plat->tx_queues_to_use; chan++) hrtimer_cancel(&priv->dma_conf.tx_queue[chan].txtimer); - stmmac_release_ptp(priv); -init_error: +ptp_error: + stmmac_stop_all_dma(priv); + return ret; }
@@ -8326,13 +8346,14 @@ int stmmac_resume(struct device *dev) ret = stmmac_hw_setup(ndev); if (ret < 0) { netdev_err(priv->dev, "%s: Hw setup failed\n", __func__); - stmmac_legacy_serdes_power_down(priv); - mutex_unlock(&priv->lock); - rtnl_unlock(); - return ret; + goto error_unlock; } - stmmac_init_timestamping(priv); + if (stmmac_check_timestamp_cap(priv)) { + ret = stmmac_init_timestamping(priv); + if (ret) + goto error_stop_dma; + } stmmac_init_coalesce(priv); phylink_rx_clk_stop_block(priv->phylink);
@@ -8356,6 +8377,15 @@ int stmmac_resume(struct device *dev) netif_device_attach(ndev); return 0; + +error_stop_dma: + stmmac_stop_all_dma(priv); +error_unlock: + stmmac_legacy_serdes_power_down(priv); + mutex_unlock(&priv->lock); + rtnl_unlock(); + + return ret; } EXPORT_SYMBOL_GPL(stmmac_resume);
--- base-commit: 641d03105cc0d2437e32fdeec164f91a4ccef6c4 change-id: 20260904-stmmac-ptp-error-propagate-6c0147b4ce29 Best regards, -- Lorenzo Bianconi [off-list ref]