blob: 7a8ce920c49e709b067321ae91306153f4f24390 [file] [log] [blame]
/* PTP 1588 clock using the Renesas Ethernet AVB
*
* Copyright (C) 2013-2015 Renesas Electronics Corporation
* Copyright (C) 2015 Renesas Solutions Corp.
* Copyright (C) 2015 Cogent Embedded, Inc. <source@cogentembedded.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*/
#include "ravb.h"
static int ravb_ptp_tcr_request(struct ravb_private *priv, u32 request)
{
struct net_device *ndev = priv->ndev;
int error;
error = ravb_wait(ndev, GCCR, GCCR_TCR, GCCR_TCR_NOREQ);
if (error)
return error;
ravb_write(ndev, ravb_read(ndev, GCCR) | request, GCCR);
return ravb_wait(ndev, GCCR, GCCR_TCR, GCCR_TCR_NOREQ);
}
/* Caller must hold the lock */
static int ravb_ptp_time_read(struct ravb_private *priv, struct timespec64 *ts)
{
struct net_device *ndev = priv->ndev;
int error;
error = ravb_ptp_tcr_request(priv, GCCR_TCR_CAPTURE);
if (error)
return error;
ts->tv_nsec = ravb_read(ndev, GCT0);
ts->tv_sec = ravb_read(ndev, GCT1) |
((s64)ravb_read(ndev, GCT2) << 32);
return 0;
}
/* Caller must hold the lock */
static int ravb_ptp_time_write(struct ravb_private *priv,
const struct timespec64 *ts)
{
struct net_device *ndev = priv->ndev;
int error;
u32 gccr;
error = ravb_ptp_tcr_request(priv, GCCR_TCR_RESET);
if (error)
return error;
gccr = ravb_read(ndev, GCCR);
if (gccr & GCCR_LTO)
return -EBUSY;
ravb_write(ndev, ts->tv_nsec, GTO0);
ravb_write(ndev, ts->tv_sec, GTO1);
ravb_write(ndev, (ts->tv_sec >> 32) & 0xffff, GTO2);
ravb_write(ndev, gccr | GCCR_LTO, GCCR);
return 0;
}
/* Caller must hold the lock */
static int ravb_ptp_update_compare(struct ravb_private *priv, u32 ns)
{
struct net_device *ndev = priv->ndev;
/* When the comparison value (GPTC.PTCV) is in range of
* [x-1 to x+1] (x is the configured increment value in
* GTI.TIV), it may happen that a comparison match is
* not detected when the timer wraps around.
*/
u32 gti_ns_plus_1 = (priv->ptp.current_addend >> 20) + 1;
u32 gccr;
if (ns < gti_ns_plus_1)
ns = gti_ns_plus_1;
else if (ns > 0 - gti_ns_plus_1)
ns = 0 - gti_ns_plus_1;
gccr = ravb_read(ndev, GCCR);
if (gccr & GCCR_LPTC)
return -EBUSY;
ravb_write(ndev, ns, GPTC);
ravb_write(ndev, gccr | GCCR_LPTC, GCCR);
return 0;
}
/* PTP clock operations */
static int ravb_ptp_adjfreq(struct ptp_clock_info *ptp, s32 ppb)
{
struct ravb_private *priv = container_of(ptp, struct ravb_private,
ptp.info);
struct net_device *ndev = priv->ndev;
unsigned long flags;
u32 diff, addend;
bool neg_adj = false;
u32 gccr;
if (ppb < 0) {
neg_adj = true;
ppb = -ppb;
}
addend = priv->ptp.default_addend;
diff = div_u64((u64)addend * ppb, NSEC_PER_SEC);
addend = neg_adj ? addend - diff : addend + diff;
spin_lock_irqsave(&priv->lock, flags);
priv->ptp.current_addend = addend;
gccr = ravb_read(ndev, GCCR);
if (gccr & GCCR_LTI) {
spin_unlock_irqrestore(&priv->lock, flags);
return -EBUSY;
}
ravb_write(ndev, addend & GTI_TIV, GTI);
ravb_write(ndev, gccr | GCCR_LTI, GCCR);
spin_unlock_irqrestore(&priv->lock, flags);
return 0;
}
static int ravb_ptp_adjtime(struct ptp_clock_info *ptp, s64 delta)
{
struct ravb_private *priv = container_of(ptp, struct ravb_private,
ptp.info);
struct timespec64 ts;
unsigned long flags;
int error;
spin_lock_irqsave(&priv->lock, flags);
error = ravb_ptp_time_read(priv, &ts);
if (!error) {
u64 now = ktime_to_ns(timespec64_to_ktime(ts));
ts = ns_to_timespec64(now + delta);
error = ravb_ptp_time_write(priv, &ts);
}
spin_unlock_irqrestore(&priv->lock, flags);
return error;
}
static int ravb_ptp_gettime64(struct ptp_clock_info *ptp, struct timespec64 *ts)
{
struct ravb_private *priv = container_of(ptp, struct ravb_private,
ptp.info);
unsigned long flags;
int error;
spin_lock_irqsave(&priv->lock, flags);
error = ravb_ptp_time_read(priv, ts);
spin_unlock_irqrestore(&priv->lock, flags);
return error;
}
static int ravb_ptp_settime64(struct ptp_clock_info *ptp,
const struct timespec64 *ts)
{
struct ravb_private *priv = container_of(ptp, struct ravb_private,
ptp.info);
unsigned long flags;
int error;
spin_lock_irqsave(&priv->lock, flags);
error = ravb_ptp_time_write(priv, ts);
spin_unlock_irqrestore(&priv->lock, flags);
return error;
}
static int ravb_ptp_extts(struct ptp_clock_info *ptp,
struct ptp_extts_request *req, int on)
{
struct ravb_private *priv = container_of(ptp, struct ravb_private,
ptp.info);
struct net_device *ndev = priv->ndev;
unsigned long flags;
u32 gic;
if (req->index)
return -EINVAL;
if (priv->ptp.extts[req->index] == on)
return 0;
priv->ptp.extts[req->index] = on;
spin_lock_irqsave(&priv->lock, flags);
gic = ravb_read(ndev, GIC);
if (on)
gic |= GIC_PTCE;
else
gic &= ~GIC_PTCE;
ravb_write(ndev, gic, GIC);
mmiowb();
spin_unlock_irqrestore(&priv->lock, flags);
return 0;
}
static int ravb_ptp_perout(struct ptp_clock_info *ptp,
struct ptp_perout_request *req, int on)
{
struct ravb_private *priv = container_of(ptp, struct ravb_private,
ptp.info);
struct net_device *ndev = priv->ndev;
struct ravb_ptp_perout *perout;
unsigned long flags;
int error = 0;
u32 gic;
if (req->index)
return -EINVAL;
if (on) {
u64 start_ns;
u64 period_ns;
start_ns = req->start.sec * NSEC_PER_SEC + req->start.nsec;
period_ns = req->period.sec * NSEC_PER_SEC + req->period.nsec;
if (start_ns > U32_MAX) {
netdev_warn(ndev,
"ptp: start value (nsec) is over limit. Maximum size of start is only 32 bits\n");
return -ERANGE;
}
if (period_ns > U32_MAX) {
netdev_warn(ndev,
"ptp: period value (nsec) is over limit. Maximum size of period is only 32 bits\n");
return -ERANGE;
}
spin_lock_irqsave(&priv->lock, flags);
perout = &priv->ptp.perout[req->index];
perout->target = (u32)start_ns;
perout->period = (u32)period_ns;
error = ravb_ptp_update_compare(priv, (u32)start_ns);
if (!error) {
/* Unmask interrupt */
gic = ravb_read(ndev, GIC);
gic |= GIC_PTME;
ravb_write(ndev, gic, GIC);
}
} else {
spin_lock_irqsave(&priv->lock, flags);
perout = &priv->ptp.perout[req->index];
perout->period = 0;
/* Mask interrupt */
gic = ravb_read(ndev, GIC);
gic &= ~GIC_PTME;
ravb_write(ndev, gic, GIC);
}
mmiowb();
spin_unlock_irqrestore(&priv->lock, flags);
return error;
}
static int ravb_ptp_enable(struct ptp_clock_info *ptp,
struct ptp_clock_request *req, int on)
{
switch (req->type) {
case PTP_CLK_REQ_EXTTS:
return ravb_ptp_extts(ptp, &req->extts, on);
case PTP_CLK_REQ_PEROUT:
return ravb_ptp_perout(ptp, &req->perout, on);
default:
return -EOPNOTSUPP;
}
}
static const struct ptp_clock_info ravb_ptp_info = {
.owner = THIS_MODULE,
.name = "ravb clock",
.max_adj = 50000000,
.n_ext_ts = N_EXT_TS,
.n_per_out = N_PER_OUT,
.adjfreq = ravb_ptp_adjfreq,
.adjtime = ravb_ptp_adjtime,
.gettime64 = ravb_ptp_gettime64,
.settime64 = ravb_ptp_settime64,
.enable = ravb_ptp_enable,
};
/* Caller must hold the lock */
irqreturn_t ravb_ptp_interrupt(struct net_device *ndev)
{
struct ravb_private *priv = netdev_priv(ndev);
u32 gis = ravb_read(ndev, GIS);
gis &= ravb_read(ndev, GIC);
if (gis & GIS_PTCF) {
struct ptp_clock_event event;
event.type = PTP_CLOCK_EXTTS;
event.index = 0;
event.timestamp = ravb_read(ndev, GCPT);
ptp_clock_event(priv->ptp.clock, &event);
}
if (gis & GIS_PTMF) {
struct ravb_ptp_perout *perout = priv->ptp.perout;
if (perout->period) {
perout->target += perout->period;
ravb_ptp_update_compare(priv, perout->target);
}
}
if (gis) {
ravb_write(ndev, ~gis, GIS);
return IRQ_HANDLED;
}
return IRQ_NONE;
}
void ravb_ptp_init(struct net_device *ndev, struct platform_device *pdev)
{
struct ravb_private *priv = netdev_priv(ndev);
unsigned long flags;
u32 gccr;
priv->ptp.info = ravb_ptp_info;
priv->ptp.default_addend = ravb_read(ndev, GTI);
priv->ptp.current_addend = priv->ptp.default_addend;
spin_lock_irqsave(&priv->lock, flags);
ravb_wait(ndev, GCCR, GCCR_TCR, GCCR_TCR_NOREQ);
gccr = ravb_read(ndev, GCCR) & ~GCCR_TCSS;
ravb_write(ndev, gccr | GCCR_TCSS_ADJGPTP, GCCR);
mmiowb();
spin_unlock_irqrestore(&priv->lock, flags);
priv->ptp.clock = ptp_clock_register(&priv->ptp.info, &pdev->dev);
}
void ravb_ptp_stop(struct net_device *ndev)
{
struct ravb_private *priv = netdev_priv(ndev);
ravb_write(ndev, 0, GIC);
ravb_write(ndev, 0, GIS);
ptp_clock_unregister(priv->ptp.clock);
}