On Fri, 21 Aug 2015, Christopher S. Hall wrote:
> From: Christopher Hall <christopher.s.h...@intel.com>
> 
> Add getsynctime() PTP device callback to cross timestamp system device
>       clock using ART translation depends on platform being >= SPT
>       and having ART
> 
> getsynctime() reads ART (TSC-derived)/device cross timestamp and
>       converts to realtime/device time reporting cross timestamp to
>       PTP driver

See patch 1/4
 
> index 25a0ad5..228f3f3 100644
> --- a/drivers/net/ethernet/intel/e1000e/ptp.c
> +++ b/drivers/net/ethernet/intel/e1000e/ptp.c
> @@ -25,6 +25,8 @@
>   */
>  
>  #include "e1000.h"
> +#include <asm/tsc.h>
> +#include <linux/timekeeping.h>

The usual way to order includes is:

#include <linux/timekeeping.h>

#include <asm/tsc.h>

#include "e1000.h"

> +/**
> + * e1000e_phc_getsynctime - Reads the current time from the hardware clock 
> and
> + * correlated system time
> + * @ptp: ptp clock structure
> + * @devts: timespec structure to hold the current device time value
> + * @systs: timespec structure to hold the current system time value
> + *
> + * Read device and system (ART) clock simultaneously and return the correct
> + * clock values in ns after converting into a struct timespec.
> + **/
> +static int e1000e_phc_getsynctime(struct ptp_clock_info *ptp,
> +                               struct timespec64 *devts,
> +                               struct timespec64 *systs)
> +{
> +     struct e1000_adapter *adapter = container_of(ptp, struct e1000_adapter,
> +                                                  ptp_clock_info);
> +     unsigned long flags;
> +     u32 remainder;
> +     struct correlated_ts art_correlated_ts;
> +     u64 device_time;
> +     int ret;
> +
> +     art_correlated_ts.get_ts = e1000e_phc_get_ts;
> +     art_correlated_ts.private = adapter;
> +     ret = get_correlated_timestamp(&art_correlated_ts,
> +                                    &art_timestamper);

Pointless line break

> +     if (ret != 0)
> +             goto bail;

What's the purpose of this goto?

       if (ret)
                return ret;

is completely sufficient.

> +
> +     systs->tv_sec =
> +             div_u64_rem(art_correlated_ts.system_real.tv64,
> +                         NSEC_PER_SEC, &remainder);
> +     systs->tv_nsec = remainder;

ktime_to_timespec64() perhaps?

And please move that conversion to the ptp ioctl

> +     spin_lock_irqsave(&adapter->systim_lock, flags);
> +     device_time = timecounter_cyc2time(&adapter->tc,
> +                                        art_correlated_ts.device_ts);

....

> +     /* CPU must have ART and GBe must be from Sunrise Point or greater */
> +     if (hw->mac.type < e1000_pch_spt || !cpu_has_art)
> +             adapter->ptp_clock_info.getsynctime64 = NULL;

We do it the other way round. We leave the default NULL and update it
if we detect the feature.

Thanks,

        tglx
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Reply via email to