On Thu, 2015-02-26 at 10:36 -0800, Gary E. Miller wrote: > Yo Jacob E! > > On Thu, 26 Feb 2015 18:11:06 +0000 > "Keller, Jacob E" <jacob.e.kel...@intel.com> wrote: > > > The absolute minimum > > > > HWTSTAMP_TX_ON for Transmit timestamps > > > > and > > > > HWTSTAMP_FILTER_V2_L4_SYNC if you are a slave in L4 (ipv4 or ipv6) > > mode. You would never be able to support master. > > > > HWTSTAMP_FILTER_V2_L4_DELAY_REQ if you are a master, in L4, never able > > to be a slave. > > > > (swap those for L2 if you are in L2 mode) > > > > This wouldn't work with P2P delay model, because those are yet another > > type of packet you'd have to Rx timestamp. > > > > The "best" minimal answer is "HWTSTAMP_FILTER_V2_EVENT" > > > > Almost all hardware supports some form of V2_EVENT, and honestly I > > wouldn't suggest hardware that does not support V2_EVENT, as it > > requires ptp4l to reconfigure timestamp mode upon state change from > > master to slave if you can't support the generic V2_EVENT. > > Hmm, clearly a swamp. Somebody should be collecting a list of > known working cards... > > And I am confused again. See below for my I210. > > kong linuxptp # ethtool -T eth1 > Time stamping parameters for eth1: > Capabilities: > hardware-transmit (SOF_TIMESTAMPING_TX_HARDWARE) > software-transmit (SOF_TIMESTAMPING_TX_SOFTWARE) > hardware-receive (SOF_TIMESTAMPING_RX_HARDWARE) > software-receive (SOF_TIMESTAMPING_RX_SOFTWARE) > software-system-clock (SOF_TIMESTAMPING_SOFTWARE) > hardware-raw-clock (SOF_TIMESTAMPING_RAW_HARDWARE) > PTP Hardware Clock: 1 > Hardware Transmit Timestamp Modes: > off (HWTSTAMP_TX_OFF) > on (HWTSTAMP_TX_ON) > Hardware Receive Filter Modes: > none (HWTSTAMP_FILTER_NONE) > all (HWTSTAMP_FILTER_ALL) > > Does HWTSTAMP_FILTER_ALL implicitly include HWTSTAMP_V2_EVENT, > HWTSTAMP_FILTER_V2_L4_SYNC, HWTSTAMP_FILTER_V2_L4_DELAY_REQ? >
Yes.. ish. HWTSTAMP_FILTER_ALL means "all packets will be timestamped" FILTER_V2_EVENT means: "all V2 Event packets will be timestamped" This is the most generic filter outside of just providing timestamps for all packets. Filters are what modes of "filtering" the hardware supports to enable timestamps. When you enable a filter, it means the hardware will timestamp *at least* the requisite filter. ie: Hardware that enables FILTER_ALL is guaranteed to timestamp all packets. Hardware that enables FILTER_V2_EVENT timestamps all V2 event packets. Hardware is allowed to timestamp more if it needs to (ie: be more generic) but must timestamp at least what the filter represents. Old hardware only supported doing one type at a time. Ie: V2_L4_SYNC or "V2_L4_DELAY_REQ" full PTP protocol requires timestamps on the receipt of Sync messages, ans on the receipt of Delay Request messages, and (for P2P mode) on the receipt of Peer Delay request and peer delay response messages. It's complicated because of variety of available hardware and attempting to be able to support the various combinations. Most "good" hardware supports at least V2_EVENT (or ALL) Regards, Jake > RGDS > GARY > --------------------------------------------------------------------------- > Gary E. Miller Rellim 109 NW Wilmington Ave., Suite E, Bend, OR 97701 > g...@rellim.com Tel:+1(541)382-8588 ------------------------------------------------------------------------------ Dive into the World of Parallel Programming The Go Parallel Website, sponsored by Intel and developed in partnership with Slashdot Media, is your hub for all things parallel software development, from weekly thought leadership blogs to news, videos, case studies, tutorials and more. Take a look and join the conversation now. http://goparallel.sourceforge.net/ _______________________________________________ Linuxptp-devel mailing list Linuxptp-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/linuxptp-devel
