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Commit 407ada45 authored by Alessandro Rubini's avatar Alessandro Rubini
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doc: reviewed; minor updates 

Signed-off-by: Alessandro Rubini's avatarAlessandro Rubini <rubini@gnudd.com>
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doc/ppsi-manual.in
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......@@ -56,12 +56,12 @@
@node Top
@top Introduction
PPSi (PTP Ported to Silicon) is an application which, in
PPSi (@sc{ptp} Ported to Silicon) is an application which, in
its basic operation, implements @sc{ieee} 1588 specification in a way
that is portable to several architectures, including OS-less ones.
This manual is mainly aimed at developers: people who are working with
PTP and/or White Rabbit and need to use the protocol in their own
@sc{ptp} and/or White Rabbit and need to use the protocol in their own
hardware or software environments. Users who simply run PPSi on the host
may want to read @ref{Command Line} and little else.
......@@ -75,14 +75,14 @@ shortened to @i{WR} in this manual.
WR is a multi-lab research project that aims at synchronizing
thousands of I/O devices distributed in a network several kilometers
wide; its software protocol is an extension of PTP. A WR network is
wide; its software protocol is an extension of @sc{ptp}. A WR network is
made up of two devices: the @i{WR Switch} and the @i{WR Node}. White
Rabbit is developed at ohwr.org:
@t{http://www.ohwr.org/projects/white-rabbit}.
The WR switch is an 18-ports Gigabit Ethernet switch that runs
@sc{wr-ptp} as a Linux process, synchronizing each Ethernet link as
either a PTP master or a PTP slave (it is a @i{boundary clock}). The
either a @sc{ptp} master or a @sc{ptp} slave (it is a @i{boundary clock}). The
WR node is an I/O device that includes a soft core that runs @sc{wr-ptp}
in @i{freestanding} mode (i.e., without an operating system).
......@@ -193,9 +193,9 @@ The package currently supports the following architectures:
@end table
We plan, over time, to support microcontrollers (Danilo Sabato is
working on ARM7 and Cortex-M) and @i{bare-arm} (to be tested on the WR
switch).
We plan, over time, to support microcontrollers (a beta version for
ARM7 is working, and we are considering Cortex-M) and @i{bare-arm} (to
be tested on the WR switch).
@c ==========================================================================
@node Protocols
......@@ -212,7 +212,7 @@ Source files in that directory may override the implementation for the
standard protocol (which lives in @t{proto-standard}) to provide their
own functionalities. To simplify writing extensions, the @i{proto-standard}
functions already provide @i{hooks} so the extension itself can provide
callbacks while still using the basic PTP engine.
callbacks while still using the basic @sc{ptp} engine.
The set of callbacks is currently based on the needs of
WR, but we are willing to accept patches to provide more hooks as
needed.
......@@ -266,9 +266,9 @@ unfair to hide them.
@table @r
@item Support standard PTP and extensions.
@item Support standard @sc{ptp} and extensions.
Each protocol extension should fall back to standard PTP when
Each protocol extension should fall back to standard @sc{ptp} when
it detects that its peers are not able to speak the extended
protocol. We don't plan to support more than one extensions in
a single build: it would be just an academic exercise until
......@@ -344,10 +344,13 @@ As of 2013-05 the project suffers from these known bugs:
@itemize
@item All frames must be sent according to a pseudo-random distribution;
this is mostly in place but mut be audited project-wide.
@item We removed @i{peer-delay} support. Maybe this is a feature, we
are still shaping our mind about that, but for the time being we
don't plan to support peer-delay because it would be academic and
untested in our environments.
@item We removed @i{peer-delay} support. We plan to add it back, and
actually move White Rabbit to use @i{peer-delay} @sc{ptp} instead of
@i{end-to-end} @sc{ptp}.
@item The servo for standard-@sc{ptp} must be audited. Pietro Fezzardi
is working on @i{arch-sim} to simulate network transactions and
make serious work on the servo algorithm and parameters.
@item @sc{udp} over @sc{IPV6} is not yet supported.
@end itemize
@c ##########################################################################
......@@ -373,7 +376,7 @@ two example configuration files in its own @t{etc/} subdirectory.
Configuration is made of of global options and port-specific options.
To configure a port, use @t{port <name>} followed by its options.
The parser allocates a new PTP state machine for each new port, but
The parser allocates a new @sc{ptp} state machine for each new port, but
allows changing configuration of an existing port. For instance, to
enable frame diagnostics for a specific port, you can use:
......@@ -572,8 +575,8 @@ separately with ``@t{make -C tools}''.
@node ptpdump
@section ptpdump
This is a sniffer for PTP frames. It reports all Ethernet frames and
UDP datagrams that talk PTP, from a specific network interface. The
This is a sniffer for @sc{ptp} frames. It reports all Ethernet frames and
UDP datagrams that talk @sc{ptp}, from a specific network interface. The
output format is line-oriented to help running @i{grep} over log
files. The number of blank lines between frames depends on how much
time elapsed between them; this should help identifying sync/follow-up
......@@ -660,7 +663,7 @@ synchronization of two or more computers, but please note that the
user-space software-only approach shows some jitter; on my systems the
delay is usually a few microseconds, up to around a dozen (in general,
use of the parallel port has less delay and less jitter). In any case
this offers a second source to check what NTP or PTP daemons report.
this offers a second source to check what NTP or @sc{ptp} daemons report.
@c ==========================================================================
@node jmptime
......@@ -914,7 +917,7 @@ the suggested "CamelCase" form. Similarly, the typedefs are left, even
if they are really a pain to deal with. Most of this stuff is in
include/ppsi/ieee1588_types.h file.
The mostly used prefix is @t{pp_}, the short prefix for 'Portable PTP',
The mostly used prefix is @t{pp_}, the short prefix for 'Portable @sc{ptp}',
which is used for every function related to the algorithm itself (but
not in the architecture-specific code).
......@@ -969,16 +972,29 @@ a list of the other ones please see the help message.
@table @t
@item -f <file>
Read configuration file. The program can read several
configuration files. If no @t{-f} is passed, it tries to
read a configuration file from the standard places:
@t{/wr/etc/ppsi.conf} if White Rabbit, and @t{/etc/ppsi.conf}.
@item -C <config-item>
Pass a single configuration item, or several of them using
the semicolon as separator. See @ref{Configuration} for details.
@item -d
Diagnostics. This options receives the string of diagnostic
levels for fsm, time, frames, servo, bmc, extension (in that order).
See @ref{Diagnostic Macros} for detail.
See @ref{Diagnostic Macros} for details.
@item -b <ifname>
Specify which interface to use, for Ethernet mode (default:
architecture-dependent, but @t{eth0} for Linux builds).
architecture-dependent, but @t{eth0} for Linux builds). This
option can only be used in single-port operation.
@item -e
......
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