This is a note to let you know that I've just added the patch titled net: fec: Reload PTP registers after link-state change to the 6.6-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: net-fec-reload-ptp-registers-after-link-state-change.patch and it can be found in the queue-6.6 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit df7f4005a02af3dfda9edb9f7af8b3afac8f0f11 Author: Csókás, Bence <csokas.bence@xxxxxxxxx> Date: Tue Sep 24 11:37:06 2024 +0200 net: fec: Reload PTP registers after link-state change [ Upstream commit d9335d0232d2da605585eea1518ac6733518f938 ] On link-state change, the controller gets reset, which clears all PTP registers, including PHC time, calibrated clock correction values etc. For correct IEEE 1588 operation we need to restore these after the reset. Fixes: 6605b730c061 ("FEC: Add time stamping code and a PTP hardware clock") Signed-off-by: Csókás, Bence <csokas.bence@xxxxxxxxx> Reviewed-by: Wei Fang <wei.fang@xxxxxxx> Link: https://patch.msgid.link/20240924093705.2897329-2-csokas.bence@xxxxxxxxx Signed-off-by: Paolo Abeni <pabeni@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/net/ethernet/freescale/fec.h b/drivers/net/ethernet/freescale/fec.h index cb58696ec03b2..733af928caffc 100644 --- a/drivers/net/ethernet/freescale/fec.h +++ b/drivers/net/ethernet/freescale/fec.h @@ -693,6 +693,9 @@ struct fec_enet_private { struct { int pps_enable; + u64 ns_sys, ns_phc; + u32 at_corr; + u8 at_inc_corr; } ptp_saved_state; u64 ethtool_stats[]; diff --git a/drivers/net/ethernet/freescale/fec_ptp.c b/drivers/net/ethernet/freescale/fec_ptp.c index 8027b532de078..5e8fac50f945d 100644 --- a/drivers/net/ethernet/freescale/fec_ptp.c +++ b/drivers/net/ethernet/freescale/fec_ptp.c @@ -773,24 +773,44 @@ void fec_ptp_init(struct platform_device *pdev, int irq_idx) void fec_ptp_save_state(struct fec_enet_private *fep) { unsigned long flags; + u32 atime_inc_corr; spin_lock_irqsave(&fep->tmreg_lock, flags); fep->ptp_saved_state.pps_enable = fep->pps_enable; + fep->ptp_saved_state.ns_phc = timecounter_read(&fep->tc); + fep->ptp_saved_state.ns_sys = ktime_get_ns(); + + fep->ptp_saved_state.at_corr = readl(fep->hwp + FEC_ATIME_CORR); + atime_inc_corr = readl(fep->hwp + FEC_ATIME_INC) & FEC_T_INC_CORR_MASK; + fep->ptp_saved_state.at_inc_corr = (u8)(atime_inc_corr >> FEC_T_INC_CORR_OFFSET); + spin_unlock_irqrestore(&fep->tmreg_lock, flags); } /* Restore PTP functionality after a reset */ void fec_ptp_restore_state(struct fec_enet_private *fep) { + u32 atime_inc = readl(fep->hwp + FEC_ATIME_INC) & FEC_T_INC_MASK; unsigned long flags; + u32 counter; + u64 ns; spin_lock_irqsave(&fep->tmreg_lock, flags); /* Reset turned it off, so adjust our status flag */ fep->pps_enable = 0; + writel(fep->ptp_saved_state.at_corr, fep->hwp + FEC_ATIME_CORR); + atime_inc |= ((u32)fep->ptp_saved_state.at_inc_corr) << FEC_T_INC_CORR_OFFSET; + writel(atime_inc, fep->hwp + FEC_ATIME_INC); + + ns = ktime_get_ns() - fep->ptp_saved_state.ns_sys + fep->ptp_saved_state.ns_phc; + counter = ns & fep->cc.mask; + writel(counter, fep->hwp + FEC_ATIME); + timecounter_init(&fep->tc, &fep->cc, ns); + spin_unlock_irqrestore(&fep->tmreg_lock, flags); /* Restart PPS if needed */