| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Date: Fri, 26 Sep 2014 14:31:46 +0000
From: "Frank.Li@...escale.com" <Frank.Li@...escale.com>
To: "luwei.zhou@...escale.com" <luwei.zhou@...escale.com>,
"davem@...emloft.net" <davem@...emloft.net>,
"richardcochran@...il.com" <richardcochran@...il.com>
CC: "netdev@...r.kernel.org" <netdev@...r.kernel.org>,
"shawn.guo@...aro.org" <shawn.guo@...aro.org>,
"bhutchings@...arflare.com" <bhutchings@...arflare.com>,
"Fabio.Estevam@...escale.com" <Fabio.Estevam@...escale.com>,
"fugang.duan@...escale.com" <fugang.duan@...escale.com>,
"stephen@...workplumber.org" <stephen@...workplumber.org>
Subject: RE: [PATCH v1 2/4] net: fec: ptp: Use hardware algorithm to adjust
PTP counter.
>
> Hi Frank,
>
> I ran checkpatch and it can pass. I will update it in the next version.
>
Don't top post message in community mail list.
Frank Li
> Luwei
> Best Regards
>
> -----Original Message-----
> From: Li Frank-B20596
> Sent: Thursday, September 25, 2014 9:30 PM
> To: Zhou Luwei-B45643; davem@...emloft.net; richardcochran@...il.com
> Cc: netdev@...r.kernel.org; shawn.guo@...aro.org; bhutchings@...arflare.com;
> Estevam Fabio-R49496; Duan Fugang-B38611; stephen@...workplumber.org
> Subject: RE: [PATCH v1 2/4] net: fec: ptp: Use hardware algorithm to adjust PTP
> counter.
>
>
>
> > -----Original Message-----
> > From: Luwei Zhou [mailto:b45643@...escale.com]
> > Sent: Thursday, September 25, 2014 3:10 AM
> > To: davem@...emloft.net; richardcochran@...il.com
> > Cc: netdev@...r.kernel.org; shawn.guo@...aro.org;
> > bhutchings@...arflare.com; Estevam Fabio-R49496; Duan Fugang-B38611;
> > Li Frank-B20596; stephen@...workplumber.org
> > Subject: [PATCH v1 2/4] net: fec: ptp: Use hardware algorithm to
> > adjust PTP counter.
> >
> > The FEC IP supports hardware adjustment for ptp timer. Refer to the
> > description of ENET_ATCOR and ENET_ATINC registers in the spec about the
> hardware adjustment.
> > This patch uses hardware support to adjust the ptp offset and
> > frequency on the slave side.
> >
> > Signed-off-by: Luwei Zhou <b45643@...escale.com>
> > Signed-off-by: Frank Li <Frank.Li@...escale.com>
> > Signed-off-by: Fugang Duan <b38611@...escale.com>
> > ---
> > drivers/net/ethernet/freescale/fec_ptp.c | 68
> > +++++++++++++++++++++++++++-----
> > 1 file changed, 58 insertions(+), 10 deletions(-)
> >
> > diff --git a/drivers/net/ethernet/freescale/fec_ptp.c
> > b/drivers/net/ethernet/freescale/fec_ptp.c
> > index 8016bdd..e2bf786 100644
> > --- a/drivers/net/ethernet/freescale/fec_ptp.c
> > +++ b/drivers/net/ethernet/freescale/fec_ptp.c
> > @@ -71,6 +71,7 @@
> >
> > #define FEC_CC_MULT (1 << 31)
> > #define FEC_COUNTER_PERIOD (1 << 31)
> > +#define FEC_T_PERIOD_ONE_SEC (1000000000UL)
> > /**
> > * fec_ptp_read - read raw cycle counter (to be used by time counter)
> > * @cc: the cyclecounter structure
> > @@ -145,33 +146,65 @@ void fec_ptp_start_cyclecounter(struct net_device *ndev)
> > */
> > static int fec_ptp_adjfreq(struct ptp_clock_info *ptp, s32 ppb) {
> > - u64 diff;
> > unsigned long flags;
> > int neg_adj = 0;
> > - u32 mult = FEC_CC_MULT;
> > + u32 i, tmp;
> > + u32 ptp_ts_clk, ptp_inc;
> > + u32 corr_inc, corr_period;
> > + u32 corr_ns;
> >
> > struct fec_enet_private *fep =
> > container_of(ptp, struct fec_enet_private, ptp_caps);
> >
> > + if (ppb == 0)
> > + return 0;
> > +
> > if (ppb < 0) {
> > ppb = -ppb;
> > neg_adj = 1;
> > }
> >
> > - diff = mult;
> > - diff *= ppb;
> > - diff = div_u64(diff, 1000000000ULL);
> > + ptp_ts_clk = clk_get_rate(fep->clk_ptp);
> > + ptp_inc = FEC_T_PERIOD_ONE_SEC / ptp_ts_clk;
> > +
> > + /*
> > + * In theory, corr_inc/corr_period = ppb/FEC_T_PERIOD_ONE_SEC;
> > + * Try to find the corr_inc between 1 to ptp_inc to meet adjustment
> > + * requirement.
> > + */
> > + for (i = 1; i <= ptp_inc; i++) {
> > + if (((i * FEC_T_PERIOD_ONE_SEC) / ppb) >= ptp_inc) {
> > + corr_inc = i;
> > + corr_period = ((i * FEC_T_PERIOD_ONE_SEC) /
> > + (ptp_inc * ppb));
> > + break;
> > + }
> > + }
> > + /*
> > + * Not found? Set it to high value - double speed
> > + * correct in every clock step.
> > + */
> > + if (i > ptp_inc) {
> > + corr_inc = ptp_inc;
> > + corr_period = 1;
> > + }
> > +
> > + if (neg_adj)
> > + corr_ns = ptp_inc - corr_inc;
> > + else
> > + corr_ns = ptp_inc + corr_inc;
> >
> > spin_lock_irqsave(&fep->tmreg_lock, flags);
> > +
> > + tmp = readl(fep->hwp + FEC_ATIME_INC) & FEC_T_INC_MASK;
> > + tmp |= corr_ns << FEC_T_INC_CORR_OFFSET;
> > + writel(tmp, fep->hwp + FEC_ATIME_INC);
> > + writel(corr_period, fep->hwp + FEC_ATIME_CORR);
> > /*
> > - * dummy read to set cycle_last in tc to now.
> > - * So use adjusted mult to calculate when next call
> > - * timercounter_read.
> > + * dummy read to update the timer.
> > */
> > timecounter_read(&fep->tc);
> >
> > - fep->cc.mult = neg_adj ? mult - diff : mult + diff;
> > -
> > spin_unlock_irqrestore(&fep->tmreg_lock, flags);
> >
> > return 0;
> > @@ -190,12 +223,20 @@ static int fec_ptp_adjtime(struct ptp_clock_info
> > *ptp, s64
> > delta)
> > container_of(ptp, struct fec_enet_private, ptp_caps);
> > unsigned long flags;
> > u64 now;
> > + u32 counter;
> >
> > spin_lock_irqsave(&fep->tmreg_lock, flags);
> >
> > now = timecounter_read(&fep->tc);
> > now += delta;
> >
> > + /*
> > + * Get the timer value based on adjusted timestamp.
> > + * Update the counter with the masked value.
> > + */
>
> Comments should like
>
> /* Get the xxx
> * dds
> */
>
> First empty line is not necessary.
> Please check the other place.
>
> Did you run checkpatch script?
>
> Best regards
> Frank Li
>
> > + counter = now & fep->cc.mask;
> > + writel(counter, fep->hwp + FEC_ATIME);
> > +
> > /* reset the timecounter */
> > timecounter_init(&fep->tc, &fep->cc, now);
> >
> > @@ -246,6 +287,7 @@ static int fec_ptp_settime(struct ptp_clock_info
> > *ptp,
> >
> > u64 ns;
> > unsigned long flags;
> > + u32 counter;
> >
> > mutex_lock(&fep->ptp_clk_mutex);
> > /* Check the ptp clock */
> > @@ -256,8 +298,14 @@ static int fec_ptp_settime(struct ptp_clock_info
> > *ptp,
> >
> > ns = ts->tv_sec * 1000000000ULL;
> > ns += ts->tv_nsec;
> > + /*
> > + * Get the timer value based on timestamp.
> > + * Update the counter with the masked value.
> > + */
> > + counter = ns & fep->cc.mask;
> >
> > spin_lock_irqsave(&fep->tmreg_lock, flags);
> > + writel(counter, fep->hwp + FEC_ATIME);
> > timecounter_init(&fep->tc, &fep->cc, ns);
> > spin_unlock_irqrestore(&fep->tmreg_lock, flags);
> > mutex_unlock(&fep->ptp_clk_mutex);
> > --
> > 1.9.1
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Powered by blists - more mailing lists