+ Added information about the refresh command
	+ Deleted references about "stat cont" command ("stat" command works as it now)
	+ Modified the stat examples of "Running the Core" section

	- Add new command "refresh" to change update period of gui and stat
	- Delete "stat cont" command
	- Update "stat" command to work as older "stat cont" one
	- Update the wrc_main.c file to check if the log messages must be generated one time

Note: If you set period to 0, the log messages are only generated one time.

	- Added the NIC_PFILTER configuration option in Kconfig to decide which filter rules will be used.
	- Updated the dev/ep_pfilter.c file by using the CONFIG_NIC_PFILTER macro. This is done because packet filter does
	not work correctly if we write all rules in the CONFIG_ETHERBONE section.
	- We do not use the DROP instruction because all other packets go to NIC core.

Notes:

	- The filter rules to the wr-nic do not have the DROP instruction because all traffic
	does not go to the LM32/Etherbone is re-direct to the NIC by default.

	- The NIC_PFILTER configuration option depends on ETHERBONE one.

	- Magic number of Etherbone packets is not checked due to the number of rules. (The packet filter is not able to classify correctly)

- Added CONFIG_WRNIC in Kconfig to decide which filter rules will be use.
- Updated ep_pfilter using CONFIG_WRNIC.
- We do not use drop because all other packet goes to NIC core.

Note: filter rules to wr-nic do not have DROP instruction because all traffic
does not go to LM32/Etherbone is re-direct to NIC by default.

It becomes a problem when WRPC works in 16-bit PCS mode. In such case bitslide
value is 5bit and masking it with 0xF could cause wrong bts once in a while.

Too large value of ld.threshold causes aligning 1-PPS to a wrong, not completely
locked 10MHz clock. That produces 1-PPS output at a random place each time the
GrandMaster is re-locked.

It was too many instructions and for small frames pfilter was not able to
execute them before the end of frame.

[t24-fix]: rewritten RX timestamp linearization (phase + counter merging) algorithm to be easier to understand.

For more info, check the note in the Documents section of the wrpc-sw project on ohwr.org.

Etherbone won't fit with a full ppsi in the default RAM size for SPEC
cards. So this commit uses a ppsi hack to avoid internal ptpdump,
activating it when CONFIG_RAMSIZE is not 128kB and CONFIG_ETHERBONE is
set.

We should rather compare RAMSIZE with "< 131072", but neither gnu make
nor this version of Kconfig support numeric comparison.

This hack will soon disappera, as ppsi is gaining Kconfig support, so
wrpc-sw will be able to pass proper configuration. Also, 128kB will soon
be the default for SPEC images.
Signed-off-by: Alessandro Rubini <rubini@gnudd.com>

Previous one was not working when:
* tR and tF were both inside (0; 4000) and tR < tF
* tR and tF were both inside (4000; 8000) and tF < tR

in those cases it was calculating ttrans around falling edge instead of rising
edge. This commit fixes it.

After subtraction of transition value from linearized phase, the phase value was renormalized to 0...clock_period-1, but
not the other counters. This resulted in very rare 8ns jumps.

The phase was used backwards. Somehow this cancelled out the systematic
error introduced by the actual bug (wrong phase offset). When both bugs
are fixed the code seems to work every time.

t24p calibration finds the rising&falling edges in
dev/rxts_calibrator.c:rxts_calibration_update.  It then computes the
"transition" as (falling+rising)/2.  That is, ttrans points 25% past the
dangerous transition.  Now that value arrives in one of the three copies of
ptpd_netif_linearize_rx_timestamp (depending on build).  In this method
ttrans has +-1/4 period added to it to compute trip_lo and trip_hi.  The
intent as described by the comment (and common sense) is to avoid the rising
edge when the phase is within +-1/4 period.  Unfortunately, this code
assumes that ttrans IS the rising edge, when in fact it is the rising
edge+25%. Thus, the code ACTUALLY tests phase within 0-50%.

Signed-off-by: Alessandro Rubini <rubini@gnudd.com>

This fixes the previous commit, which prevented to build wrpc-sw with
CONFIG_PTP_NOPOSIX (silly me).
Signed-off-by: Alessandro Rubini <rubini@gnudd.com>

Signed-off-by: Alessandro Rubini <rubini@gnudd.com>

Tom's fix for helper PLL, in Slave mode it should use RX clock instead of REF clock.

Tom's fix for WR Switch makes ptracker much faster so that SPLL can handle all 18 ports.