diff options
| author | Gerhard Engleder <gerhard@engleder-embedded.com> | 2022-05-06 22:01:37 +0200 |
|---|---|---|
| committer | Paolo Abeni <pabeni@redhat.com> | 2022-05-10 09:48:08 +0200 |
| commit | 42704b26b0f1d891f6cf4ebc877dbac0d17c690d (patch) | |
| tree | 283ba260e6ab1b1add2628846ae4cabd657e12ed /drivers/ptp/ptp_private.h | |
| parent | b3552d6a3b8bd4260a971f1f70140ed3513cc4f7 (diff) | |
ptp: Add cycles support for virtual clocks
ptp vclocks require a free running time for their timecounter.
Currently only a physical clock forced to free running is supported.
If vclocks are used, then the physical clock cannot be synchronized
anymore. The synchronized time is not available in hardware in this
case. As a result, timed transmission with TAPRIO hardware support
is not possible anymore.
If hardware would support a free running time additionally to the
physical clock, then the physical clock does not need to be forced to
free running. Thus, the physical clocks can still be synchronized
while vclocks are in use.
The physical clock could be used to synchronize the time domain of the
TSN network and trigger TAPRIO. In parallel vclocks can be used to
synchronize other time domains.
Introduce support for a free running cycle counter called cycles to
physical clocks. Rework ptp vclocks to use this free running cycle
counter. Default implementation is based on time of physical clock.
Thus, behavior of ptp vclocks based on physical clocks without free
running cycle counter is identical to previous behavior.
Signed-off-by: Gerhard Engleder <gerhard@engleder-embedded.com>
Acked-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Diffstat (limited to 'drivers/ptp/ptp_private.h')
| -rw-r--r-- | drivers/ptp/ptp_private.h | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/drivers/ptp/ptp_private.h b/drivers/ptp/ptp_private.h index dba6be477067..ab47c10b3874 100644 --- a/drivers/ptp/ptp_private.h +++ b/drivers/ptp/ptp_private.h @@ -52,6 +52,7 @@ struct ptp_clock { int *vclock_index; struct mutex n_vclocks_mux; /* protect concurrent n_vclocks access */ bool is_virtual_clock; + bool has_cycles; }; #define info_to_vclock(d) container_of((d), struct ptp_vclock, info) @@ -96,6 +97,15 @@ static inline bool ptp_vclock_in_use(struct ptp_clock *ptp) return in_use; } +/* Check if ptp clock shall be free running */ +static inline bool ptp_clock_freerun(struct ptp_clock *ptp) +{ + if (ptp->has_cycles) + return false; + + return ptp_vclock_in_use(ptp); +} + extern struct class *ptp_class; /* |