Files
linux/drivers/net/ethernet/amd/xgbe/xgbe-ptp.c
Raju Rangoju 5b5ba63a54 amd-xgbe: Add PPS periodic output support
Add support for hardware PPS (Pulse Per Second) output to the
AMD XGBE driver. The implementation enables flexible periodic
output mode, exposing it via the PTP per_out interface.

The driver supports configuring PPS output using the standard
PTP subsystem, allowing precise periodic signal generation for
time synchronization applications.

The feature has been verified using the testptp tool and
oscilloscope.

Signed-off-by: Raju Rangoju <Raju.Rangoju@amd.com>
Link: https://patch.msgid.link/20250909113143.1364477-1-Raju.Rangoju@amd.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-09-14 14:29:26 -07:00

170 lines
4.3 KiB
C

// SPDX-License-Identifier: (GPL-2.0-or-later OR BSD-3-Clause)
/*
* Copyright (c) 2014-2025, Advanced Micro Devices, Inc.
* Copyright (c) 2014, Synopsys, Inc.
* All rights reserved
*/
#include <linux/clk.h>
#include <linux/clocksource.h>
#include <linux/ptp_clock_kernel.h>
#include <linux/net_tstamp.h>
#include "xgbe.h"
#include "xgbe-common.h"
static int xgbe_adjfine(struct ptp_clock_info *info, long scaled_ppm)
{
struct xgbe_prv_data *pdata = container_of(info,
struct xgbe_prv_data,
ptp_clock_info);
unsigned long flags;
u64 addend;
addend = adjust_by_scaled_ppm(pdata->tstamp_addend, scaled_ppm);
spin_lock_irqsave(&pdata->tstamp_lock, flags);
xgbe_update_tstamp_addend(pdata, addend);
spin_unlock_irqrestore(&pdata->tstamp_lock, flags);
return 0;
}
static int xgbe_adjtime(struct ptp_clock_info *info, s64 delta)
{
struct xgbe_prv_data *pdata = container_of(info,
struct xgbe_prv_data,
ptp_clock_info);
unsigned int neg_adjust = 0;
unsigned int sec, nsec;
u32 quotient, reminder;
unsigned long flags;
if (delta < 0) {
neg_adjust = 1;
delta = -delta;
}
quotient = div_u64_rem(delta, 1000000000ULL, &reminder);
sec = quotient;
nsec = reminder;
/* Negative adjustment for Hw timer register. */
if (neg_adjust) {
sec = -sec;
if (XGMAC_IOREAD_BITS(pdata, MAC_TSCR, TSCTRLSSR))
nsec = (1000000000UL - nsec);
else
nsec = (0x80000000UL - nsec);
}
nsec = (neg_adjust << 31) | nsec;
spin_lock_irqsave(&pdata->tstamp_lock, flags);
xgbe_update_tstamp_time(pdata, sec, nsec);
spin_unlock_irqrestore(&pdata->tstamp_lock, flags);
return 0;
}
static int xgbe_gettimex(struct ptp_clock_info *info, struct timespec64 *ts,
struct ptp_system_timestamp *sts)
{
struct xgbe_prv_data *pdata = container_of(info,
struct xgbe_prv_data,
ptp_clock_info);
unsigned long flags;
u64 nsec;
spin_lock_irqsave(&pdata->tstamp_lock, flags);
ptp_read_system_prets(sts);
nsec = xgbe_get_tstamp_time(pdata);
ptp_read_system_postts(sts);
spin_unlock_irqrestore(&pdata->tstamp_lock, flags);
*ts = ns_to_timespec64(nsec);
return 0;
}
static int xgbe_settime(struct ptp_clock_info *info,
const struct timespec64 *ts)
{
struct xgbe_prv_data *pdata = container_of(info,
struct xgbe_prv_data,
ptp_clock_info);
unsigned long flags;
spin_lock_irqsave(&pdata->tstamp_lock, flags);
xgbe_set_tstamp_time(pdata, ts->tv_sec, ts->tv_nsec);
spin_unlock_irqrestore(&pdata->tstamp_lock, flags);
return 0;
}
static int xgbe_enable(struct ptp_clock_info *info,
struct ptp_clock_request *request, int on)
{
struct xgbe_prv_data *pdata = container_of(info, struct xgbe_prv_data,
ptp_clock_info);
struct xgbe_pps_config *pps_cfg;
unsigned long flags;
int ret;
dev_dbg(pdata->dev, "rq->type %d on %d\n", request->type, on);
if (request->type != PTP_CLK_REQ_PEROUT)
return -EOPNOTSUPP;
pps_cfg = &pdata->pps[request->perout.index];
pps_cfg->start.tv_sec = request->perout.start.sec;
pps_cfg->start.tv_nsec = request->perout.start.nsec;
pps_cfg->period.tv_sec = request->perout.period.sec;
pps_cfg->period.tv_nsec = request->perout.period.nsec;
spin_lock_irqsave(&pdata->tstamp_lock, flags);
ret = xgbe_pps_config(pdata, pps_cfg, request->perout.index, on);
spin_unlock_irqrestore(&pdata->tstamp_lock, flags);
return ret;
}
void xgbe_ptp_register(struct xgbe_prv_data *pdata)
{
struct ptp_clock_info *info = &pdata->ptp_clock_info;
struct ptp_clock *clock;
snprintf(info->name, sizeof(info->name), "%s",
netdev_name(pdata->netdev));
info->owner = THIS_MODULE;
info->max_adj = pdata->ptpclk_rate;
info->adjfine = xgbe_adjfine;
info->adjtime = xgbe_adjtime;
info->gettimex64 = xgbe_gettimex;
info->settime64 = xgbe_settime;
info->n_per_out = pdata->hw_feat.pps_out_num;
info->n_ext_ts = pdata->hw_feat.aux_snap_num;
info->enable = xgbe_enable;
clock = ptp_clock_register(info, pdata->dev);
if (IS_ERR(clock)) {
dev_err(pdata->dev, "ptp_clock_register failed\n");
return;
}
pdata->ptp_clock = clock;
/* Disable all timestamping to start */
XGMAC_IOWRITE(pdata, MAC_TSCR, 0);
pdata->tstamp_config.tx_type = HWTSTAMP_TX_OFF;
pdata->tstamp_config.rx_filter = HWTSTAMP_FILTER_NONE;
}
void xgbe_ptp_unregister(struct xgbe_prv_data *pdata)
{
if (pdata->ptp_clock)
ptp_clock_unregister(pdata->ptp_clock);
}