stmmac_update_subsecond_increment() ignores the error returned by stmmac_config_addend(), and stmmac_init_tstamp_counter() discards the addend and system time programming errors, always returning success. A failure to program the addend (PTP_TCR_TSADDREG) or to initialize the system time counter (PTP_TCR_TSINIT) is therefore silently swallowed, leaving the hardware timestamp counter in a non-running or partially configured state while the driver keeps operating as if timestamping were up. This matters for TAPRIO/EST offloading, which derives the gate base time from the hardware timestamp counter. The same hooks are also called from the PHC callbacks: settime64 and adjfine drop the error and report success to clock_settime() and clock_adjtime(), so a dead PTP reference clock goes unnoticed by ptp4l/phc2sys. Return error codes from stmmac_update_subsecond_increment(), stmmac_init_tstamp_counter(), stmmac_dl_ts_coarse_set() and the settime64/adjfine callbacks instead of silently returning success. On failure, roll back the partially applied configuration so the hardware and the driver bookkeeping stay consistent, and report the reason through the devlink extack. Also guard against a zero sub-second increment, which would otherwise divide by zero when computing the addend. Reset the persistent timestamping state (hwts_tx_en, hwts_rx_en, tstamp_config, systime_flags and tsfupdt_coarse) when (re)initializing timestamping, so a failed init does not leave TX/RX timestamping enabled on a counter that never started. Fixes: cc4c9001ce31 ("net: stmmac: Switch stmmac_hwtimestamp to generic HW Interface Helpers") Signed-off-by: Lorenzo Bianconi --- Changes in v3: - Do not run stmmac_config_addend() in stmmac_update_subsecond_increment() error path. - Return error from stmmac_adjust_freq() and stmmac_set_time(). - Reset hw ts configuration in stmmac_init_timestamping(). - Link to v2: https://lore.kernel.org/r/20260924-stmmac-ptp-added-systime-error-v2-1-beb2a6b5f866@oss.qualcomm.com Changes in v2: - Initialize sec_inc to 0 in stmmac_restore_subsecond_increment() routine. - Link to v1: https://lore.kernel.org/r/20260920-stmmac-ptp-added-systime-error-v1-1-8ac9e7a3fce2@oss.qualcomm.com --- drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 106 ++++++++++++++++------ drivers/net/ethernet/stmicro/stmmac/stmmac_ptp.c | 10 +- 2 files changed, 84 insertions(+), 32 deletions(-) diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c index ec62fa7418f4..9741f97fa37a 100644 --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c @@ -601,31 +601,64 @@ static void stmmac_get_rx_hwtstamp(struct stmmac_priv *priv, struct dma_desc *p, } } -static void stmmac_update_subsecond_increment(struct stmmac_priv *priv) +static void stmmac_restore_subsecond_increment(struct stmmac_priv *priv, + u32 default_addend) { bool xmac = dwmac_is_xmac(priv->plat->core_type); u32 sec_inc = 0; - u64 temp = 0; + stmmac_config_addend(priv, priv->ptpaddr, default_addend); stmmac_config_hw_tstamping(priv, priv->ptpaddr, priv->systime_flags); + stmmac_config_sub_second_increment(priv, priv->ptpaddr, + priv->plat->clk_ptp_rate, + xmac, &sec_inc); + priv->default_addend = default_addend; + priv->sub_second_inc = sec_inc; +} + +static int stmmac_update_subsecond_increment(struct stmmac_priv *priv, + u32 systime_flags) +{ + bool xmac = dwmac_is_xmac(priv->plat->core_type); + u32 sec_inc = 0, val; + u64 temp = 0; + int ret; + + stmmac_config_hw_tstamping(priv, priv->ptpaddr, systime_flags); /* program Sub Second Increment reg */ stmmac_config_sub_second_increment(priv, priv->ptpaddr, priv->plat->clk_ptp_rate, xmac, &sec_inc); - temp = div_u64(1000000000ULL, sec_inc); - - /* Store sub second increment for later use */ - priv->sub_second_inc = sec_inc; + if (!sec_inc) { + ret = -EINVAL; + goto error; + } /* calculate default added value: * formula is : * addend = (2^32)/freq_div_ratio; * where, freq_div_ratio = 1e9ns/sec_inc */ + temp = div_u64(1000000000ULL, sec_inc); temp = (u64)(temp << 32); - priv->default_addend = div_u64(temp, priv->plat->clk_ptp_rate); - stmmac_config_addend(priv, priv->ptpaddr, priv->default_addend); + val = div_u64(temp, priv->plat->clk_ptp_rate); + + ret = stmmac_config_addend(priv, priv->ptpaddr, val); + if (ret) + goto error; + + priv->sub_second_inc = sec_inc; + priv->default_addend = val; + + return 0; +error: + /* Restore previous configuration */ + stmmac_config_hw_tstamping(priv, priv->ptpaddr, priv->systime_flags); + stmmac_config_sub_second_increment(priv, priv->ptpaddr, + priv->plat->clk_ptp_rate, xmac, + NULL); + return ret; } /** @@ -854,35 +887,42 @@ static int stmmac_hwtstamp_get(struct net_device *dev, /** * stmmac_init_tstamp_counter - init hardware timestamping counter * @priv: driver private structure - * @systime_flags: timestamping flags * Description: * Initialize hardware counter for packet timestamping. * This is valid as long as the interface is open and not suspended. * Will be rerun after resuming from suspend, case in which the timestamping * flags updated by stmmac_hwtstamp_set() also need to be restored. */ -static int stmmac_init_tstamp_counter(struct stmmac_priv *priv, - u32 systime_flags) +static int stmmac_init_tstamp_counter(struct stmmac_priv *priv) { + u32 default_addend = priv->default_addend; struct timespec64 now; + int ret; if (!priv->plat->clk_ptp_rate) { netdev_err(priv->dev, "Invalid PTP clock rate"); return -EINVAL; } - stmmac_config_hw_tstamping(priv, priv->ptpaddr, systime_flags); - priv->systime_flags = systime_flags; - - stmmac_update_subsecond_increment(priv); + ret = stmmac_update_subsecond_increment(priv, priv->systime_flags); + if (ret) + return ret; /* initialize system time */ ktime_get_real_ts64(&now); /* lower 32 bits of tv_sec are safe until y2106 */ - stmmac_init_systime(priv, priv->ptpaddr, (u32)now.tv_sec, now.tv_nsec); + ret = stmmac_init_systime(priv, priv->ptpaddr, (u32)now.tv_sec, + now.tv_nsec); + if (ret) + goto error; return 0; +error: + /* Restore previous configuration */ + stmmac_restore_subsecond_increment(priv, default_addend); + + return ret; } /** @@ -905,8 +945,14 @@ static int stmmac_init_timestamping(struct stmmac_priv *priv) return -EOPNOTSUPP; } - ret = stmmac_init_tstamp_counter(priv, STMMAC_HWTS_ACTIVE | - PTP_TCR_TSCFUPDT); + /* Reset hw ts configuration */ + memset(&priv->tstamp_config, 0, sizeof(priv->tstamp_config)); + priv->systime_flags = STMMAC_HWTS_ACTIVE | PTP_TCR_TSCFUPDT; + priv->tsfupdt_coarse = false; + priv->hwts_tx_en = 0; + priv->hwts_rx_en = 0; + + ret = stmmac_init_tstamp_counter(priv); if (ret) { netdev_warn(priv->dev, "PTP init failed\n"); return ret; @@ -927,10 +973,6 @@ static int stmmac_init_timestamping(struct stmmac_priv *priv) netdev_info(priv->dev, "IEEE 1588-2008 Advanced Timestamp supported\n"); - memset(&priv->tstamp_config, 0, sizeof(priv->tstamp_config)); - priv->hwts_tx_en = 0; - priv->hwts_rx_en = 0; - if (priv->plat->flags & STMMAC_FLAG_HWTSTAMP_CORRECT_LATENCY) stmmac_hwtstamp_correct_latency(priv, priv); @@ -7711,18 +7753,26 @@ static int stmmac_dl_ts_coarse_set(struct devlink *dl, u32 id, { struct stmmac_devlink_priv *dl_priv = devlink_priv(dl); struct stmmac_priv *priv = dl_priv->stmmac_priv; + u32 systime_flags = priv->systime_flags; + int ret; - priv->tsfupdt_coarse = ctx->val.vbool; - - if (priv->tsfupdt_coarse) - priv->systime_flags &= ~PTP_TCR_TSCFUPDT; + if (ctx->val.vbool) + systime_flags &= ~PTP_TCR_TSCFUPDT; else - priv->systime_flags |= PTP_TCR_TSCFUPDT; + systime_flags |= PTP_TCR_TSCFUPDT; /* In Coarse mode, we can use a smaller subsecond increment, let's * reconfigure the systime, subsecond increment and addend. */ - stmmac_update_subsecond_increment(priv); + ret = stmmac_update_subsecond_increment(priv, systime_flags); + if (ret) { + NL_SET_ERR_MSG_MOD(extack, + "failed to reconfigure PTP adjustment"); + return ret; + } + + priv->tsfupdt_coarse = ctx->val.vbool; + priv->systime_flags = systime_flags; return 0; } diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_ptp.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_ptp.c index 3bfcc9760dce..493c5d81a36b 100644 --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_ptp.c +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_ptp.c @@ -28,14 +28,15 @@ static int stmmac_adjust_freq(struct ptp_clock_info *ptp, long scaled_ppm) container_of(ptp, struct stmmac_priv, ptp_clock_ops); unsigned long flags; u32 addend; + int ret; addend = adjust_by_scaled_ppm(priv->default_addend, scaled_ppm); write_lock_irqsave(&priv->ptp_lock, flags); - stmmac_config_addend(priv, priv->ptpaddr, addend); + ret = stmmac_config_addend(priv, priv->ptpaddr, addend); write_unlock_irqrestore(&priv->ptp_lock, flags); - return 0; + return ret; } /** @@ -153,12 +154,13 @@ static int stmmac_set_time(struct ptp_clock_info *ptp, struct stmmac_priv *priv = container_of(ptp, struct stmmac_priv, ptp_clock_ops); unsigned long flags; + int ret; write_lock_irqsave(&priv->ptp_lock, flags); - stmmac_init_systime(priv, priv->ptpaddr, ts->tv_sec, ts->tv_nsec); + ret = stmmac_init_systime(priv, priv->ptpaddr, ts->tv_sec, ts->tv_nsec); write_unlock_irqrestore(&priv->ptp_lock, flags); - return 0; + return ret; } static int stmmac_enable(struct ptp_clock_info *ptp, --- base-commit: 37e02c42a00be692c06343e11779aadc45f45971 change-id: 20260920-stmmac-ptp-added-systime-error-bc9566262f2f Best regards, -- Lorenzo Bianconi