linux-stable/include/soc/mscc/ocelot_ptp.h
Vladimir Oltean 52849bcf00 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: 4e3b0468e6 ("net: mscc: PTP Hardware Clock (PHC) support")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-10-12 17:35:17 -07:00

60 lines
1.8 KiB
C

/* SPDX-License-Identifier: (GPL-2.0 OR MIT) */
/*
* Microsemi Ocelot Switch driver
*
* License: Dual MIT/GPL
* Copyright (c) 2017 Microsemi Corporation
* Copyright 2020 NXP
*/
#ifndef _MSCC_OCELOT_PTP_H_
#define _MSCC_OCELOT_PTP_H_
#include <linux/ptp_clock_kernel.h>
#include <soc/mscc/ocelot.h>
#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
#define PTP_PIN_TOD_SEC_LSB_RSZ PTP_PIN_CFG_RSZ
#define PTP_PIN_TOD_NSEC_RSZ PTP_PIN_CFG_RSZ
#define PTP_PIN_WF_HIGH_PERIOD_RSZ PTP_PIN_CFG_RSZ
#define PTP_PIN_WF_LOW_PERIOD_RSZ PTP_PIN_CFG_RSZ
#define PTP_PIN_CFG_DOM BIT(0)
#define PTP_PIN_CFG_SYNC BIT(2)
#define PTP_PIN_CFG_ACTION(x) ((x) << 3)
#define PTP_PIN_CFG_ACTION_MASK PTP_PIN_CFG_ACTION(0x7)
enum {
PTP_PIN_ACTION_IDLE = 0,
PTP_PIN_ACTION_LOAD,
PTP_PIN_ACTION_SAVE,
PTP_PIN_ACTION_CLOCK,
PTP_PIN_ACTION_DELTA,
PTP_PIN_ACTION_NOSYNC,
PTP_PIN_ACTION_SYNC,
};
#define PTP_CFG_MISC_PTP_EN BIT(2)
#define PTP_CFG_CLK_ADJ_CFG_ENA BIT(0)
#define PTP_CFG_CLK_ADJ_CFG_DIR BIT(1)
#define PTP_CFG_CLK_ADJ_FREQ_NS BIT(30)
int ocelot_ptp_gettime64(struct ptp_clock_info *ptp, struct timespec64 *ts);
int ocelot_ptp_settime64(struct ptp_clock_info *ptp,
const struct timespec64 *ts);
int ocelot_ptp_adjtime(struct ptp_clock_info *ptp, s64 delta);
int ocelot_ptp_adjfine(struct ptp_clock_info *ptp, long scaled_ppm);
int ocelot_ptp_verify(struct ptp_clock_info *ptp, unsigned int pin,
enum ptp_pin_function func, unsigned int chan);
int ocelot_ptp_enable(struct ptp_clock_info *ptp,
struct ptp_clock_request *rq, int on);
int ocelot_init_timestamp(struct ocelot *ocelot,
const struct ptp_clock_info *info);
int ocelot_deinit_timestamp(struct ocelot *ocelot);
#endif