From 72cfe5b07e856cf21a6c721a9a1357ef2a87eaff Mon Sep 17 00:00:00 2001 From: Yannick Vignon Date: Wed, 13 Jan 2021 14:15:57 +0100 Subject: [PATCH] net: stmmac: fix taprio configuration when base_time is in the past [ Upstream commit fe28c53ed71d463e187748b6b10e1130dd72ceeb ] The Synopsys TSN MAC supports Qbv base times in the past, but only up to a certain limit. As a result, a taprio qdisc configuration with a small base time (for example when treating the base time as a simple phase offset) is not applied by the hardware and silently ignored. This was observed on an NXP i.MX8MPlus device, but likely affects all TSN-variants of the MAC. Fix the issue by making sure the base time is in the future, pushing it by an integer amount of cycle times if needed. (a similar check is already done in several other taprio implementations, see for example drivers/net/ethernet/intel/igc/igc_tsn.c#L116 or drivers/net/dsa/sja1105/sja1105_ptp.h#L39). Fixes: b60189e0392f ("net: stmmac: Integrate EST with TAPRIO scheduler API") Signed-off-by: Yannick Vignon Link: https://lore.kernel.org/r/20210113131557.24651-2-yannick.vignon@oss.nxp.com Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman --- .../net/ethernet/stmicro/stmmac/stmmac_tc.c | 20 +++++++++++++++++-- 1 file changed, 18 insertions(+), 2 deletions(-) diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_tc.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_tc.c index cc27d660a818..06553d028d74 100644 --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_tc.c +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_tc.c @@ -605,7 +605,8 @@ static int tc_setup_taprio(struct stmmac_priv *priv, { u32 size, wid = priv->dma_cap.estwid, dep = priv->dma_cap.estdep; struct plat_stmmacenet_data *plat = priv->plat; - struct timespec64 time; + struct timespec64 time, current_time; + ktime_t current_time_ns; bool fpe = false; int i, ret = 0; u64 ctr; @@ -700,7 +701,22 @@ static int tc_setup_taprio(struct stmmac_priv *priv, } /* Adjust for real system time */ - time = ktime_to_timespec64(qopt->base_time); + priv->ptp_clock_ops.gettime64(&priv->ptp_clock_ops, ¤t_time); + current_time_ns = timespec64_to_ktime(current_time); + if (ktime_after(qopt->base_time, current_time_ns)) { + time = ktime_to_timespec64(qopt->base_time); + } else { + ktime_t base_time; + s64 n; + + n = div64_s64(ktime_sub_ns(current_time_ns, qopt->base_time), + qopt->cycle_time); + base_time = ktime_add_ns(qopt->base_time, + (n + 1) * qopt->cycle_time); + + time = ktime_to_timespec64(base_time); + } + priv->plat->est->btr[0] = (u32)time.tv_nsec; priv->plat->est->btr[1] = (u32)time.tv_sec;