From 52849bcf0029ccc553be304e4f804938a39112e2 Mon Sep 17 00:00:00 2001 From: Vladimir Oltean Date: Tue, 12 Oct 2021 14:40:36 +0300 Subject: net: mscc: ocelot: avoid overflowing the PTP timestamp FIFO PTP packets with 2-step TX timestamp requests are matched to packets based on the egress port number and a 6-bit timestamp identifier. All PTP timestamps are held in a common FIFO that is 128 entry deep. This patch ensures that back-to-back timestamping requests cannot exceed the hardware FIFO capacity. If that happens, simply send the packets without requesting a TX timestamp to be taken (in the case of felix, since the DSA API has a void return code in ds->ops->port_txtstamp) or drop them (in the case of ocelot). I've moved the ts_id_lock from a per-port basis to a per-switch basis, because we need separate accounting for both numbers of PTP frames in flight. And since we need locking to inc/dec the per-switch counter, that also offers protection for the per-port counter and hence there is no reason to have a per-port counter anymore. Fixes: 4e3b0468e6d7 ("net: mscc: PTP Hardware Clock (PHC) support") Signed-off-by: Vladimir Oltean Signed-off-by: Jakub Kicinski --- include/soc/mscc/ocelot.h | 5 ++++- include/soc/mscc/ocelot_ptp.h | 1 + 2 files changed, 5 insertions(+), 1 deletion(-) (limited to 'include/soc/mscc') diff --git a/include/soc/mscc/ocelot.h b/include/soc/mscc/ocelot.h index 06706a9fd5b1..b0ece85d9a76 100644 --- a/include/soc/mscc/ocelot.h +++ b/include/soc/mscc/ocelot.h @@ -603,10 +603,10 @@ struct ocelot_port { /* The VLAN ID that will be transmitted as untagged, on egress */ struct ocelot_vlan native_vlan; + unsigned int ptp_skbs_in_flight; u8 ptp_cmd; struct sk_buff_head tx_skbs; u8 ts_id; - spinlock_t ts_id_lock; phy_interface_t phy_mode; @@ -680,6 +680,9 @@ struct ocelot { struct ptp_clock *ptp_clock; struct ptp_clock_info ptp_info; struct hwtstamp_config hwtstamp_config; + unsigned int ptp_skbs_in_flight; + /* Protects the 2-step TX timestamp ID logic */ + spinlock_t ts_id_lock; /* Protects the PTP interface state */ struct mutex ptp_lock; /* Protects the PTP clock */ diff --git a/include/soc/mscc/ocelot_ptp.h b/include/soc/mscc/ocelot_ptp.h index 6e54442b49ad..f085884b1fa2 100644 --- a/include/soc/mscc/ocelot_ptp.h +++ b/include/soc/mscc/ocelot_ptp.h @@ -14,6 +14,7 @@ #include #define OCELOT_MAX_PTP_ID 63 +#define OCELOT_PTP_FIFO_SIZE 128 #define PTP_PIN_CFG_RSZ 0x20 #define PTP_PIN_TOD_SEC_MSB_RSZ PTP_PIN_CFG_RSZ -- cgit v1.2.3