From mboxrd@z Thu Jan 1 00:00:00 1970 From: Keller, Jacob E Date: Tue, 8 Nov 2016 21:56:54 +0000 Subject: [Intel-wired-lan] [PATCH net-next 0/3] PHC frequency fine tuning In-Reply-To: References: Message-ID: <1478642213.7545.36.camel@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: intel-wired-lan@osuosl.org List-ID: On Tue, 2016-11-08 at 22:49 +0100, Richard Cochran wrote: > This series expands the PTP Hardware Clock subsystem by adding a > method that passes the frequency tuning word to the the drivers > without dropping the low order bits.??Keeping those bits is useful > for > drivers whose frequency resolution is higher than 1 ppb. > Makes sense. > The appended script (below) runs a simple demonstration of the > improvement.??This test needs two Intel i210 PCIe cards installed in > the same PC, with their SDP0 pins connected by copper > wire.??Measuring > the estimated offset (from the ptp4l servo) and the true offset (from > the PPS) over one hour yields the following statistics. > > > > > ???????|???Est. Before |????Est. After |???True Before |????True > > After | > > --------+---------------+---------------+---------------+-------- > > -------| > > min????| -5.200000e+01 | -1.600000e+01 | -3.100000e+01 | > > -1.000000e+00 | > > max????| +5.700000e+01 | +2.500000e+01 | +8.500000e+01 | > > +4.000000e+01 | > > pk-pk: | +1.090000e+02 | +4.100000e+01 | +1.160000e+02 | > > +4.100000e+01 | > > mean???| +6.472222e-02 | +1.277778e-02 | +2.422083e+01 | > > +1.826083e+01 | > > stddev | +1.158006e+01 | +4.581982e+00 | +1.207708e+01 | > > +4.981435e+00 | > > Here the numbers in units of nanoseconds, and the ~20 nanosecond PPS > offset is due to input/output delays on the i210's external interface > logic. > > With the series applied, both the peak to peak error and the standard > deviation improve by a factor of more than two.??These two graphs > show > the improvement nicely. > > ? http://linuxptp.sourceforge.net/fine-tuning/fine-est.png > > ? http://linuxptp.sourceforge.net/fine-tuning/fine-tru.png > Wow, nice! I'll take a look at the actual patches in a few minutes, but this is a really nice improvement! Thanks, Jake > > Thanks, > Richard > > Richard Cochran (3): > ? ptp: Introduce a high resolution frequency adjustment method. > ? ptp: igb: Use the high resolution frequency method. > ? ptp: dp83640: Use the high resolution frequency method. > > ?drivers/net/ethernet/intel/igb/igb_ptp.c | 16 ++++++++-------- > ?drivers/net/phy/dp83640.c????????????????| 14 +++++++------- > ?drivers/ptp/ptp_clock.c??????????????????|??5 ++++- > ?include/linux/ptp_clock_kernel.h?????????|??8 ++++++++ > ?4 files changed, 27 insertions(+), 16 deletions(-) > From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Keller, Jacob E" Subject: Re: [PATCH net-next 0/3] PHC frequency fine tuning Date: Tue, 8 Nov 2016 21:56:54 +0000 Message-ID: <1478642213.7545.36.camel@intel.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Cc: "tglx@linutronix.de" , "Manfred.Rudigier@omicron.at" , "ulrik.debie-os@e2big.org" , "stefan.sorensen@spectralink.com" , "davem@davemloft.net" , "Kirsher, Jeffrey T" , "john.stultz@linaro.org" , "intel-wired-lan@lists.osuosl.org" To: "netdev@vger.kernel.org" , "richardcochran@gmail.com" Return-path: Received: from mga01.intel.com ([192.55.52.88]:3393 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751307AbcKHV44 (ORCPT ); Tue, 8 Nov 2016 16:56:56 -0500 In-Reply-To: Content-Language: en-US Content-ID: Sender: netdev-owner@vger.kernel.org List-ID: T24gVHVlLCAyMDE2LTExLTA4IGF0IDIyOjQ5ICswMTAwLCBSaWNoYXJkIENvY2hyYW4gd3JvdGU6 DQo+IFRoaXMgc2VyaWVzIGV4cGFuZHMgdGhlIFBUUCBIYXJkd2FyZSBDbG9jayBzdWJzeXN0ZW0g YnkgYWRkaW5nIGENCj4gbWV0aG9kIHRoYXQgcGFzc2VzIHRoZSBmcmVxdWVuY3kgdHVuaW5nIHdv cmQgdG8gdGhlIHRoZSBkcml2ZXJzDQo+IHdpdGhvdXQgZHJvcHBpbmcgdGhlIGxvdyBvcmRlciBi aXRzLsKgwqBLZWVwaW5nIHRob3NlIGJpdHMgaXMgdXNlZnVsDQo+IGZvcg0KPiBkcml2ZXJzIHdo b3NlIGZyZXF1ZW5jeSByZXNvbHV0aW9uIGlzIGhpZ2hlciB0aGFuIDEgcHBiLg0KPiANCg0KTWFr ZXMgc2Vuc2UuDQoNCj4gVGhlIGFwcGVuZGVkIHNjcmlwdCAoYmVsb3cpIHJ1bnMgYSBzaW1wbGUg ZGVtb25zdHJhdGlvbiBvZiB0aGUNCj4gaW1wcm92ZW1lbnQuwqDCoFRoaXMgdGVzdCBuZWVkcyB0 d28gSW50ZWwgaTIxMCBQQ0llIGNhcmRzIGluc3RhbGxlZCBpbg0KPiB0aGUgc2FtZSBQQywgd2l0 aCB0aGVpciBTRFAwIHBpbnMgY29ubmVjdGVkIGJ5IGNvcHBlcg0KPiB3aXJlLsKgwqBNZWFzdXJp bmcNCj4gdGhlIGVzdGltYXRlZCBvZmZzZXQgKGZyb20gdGhlIHB0cDRsIHNlcnZvKSBhbmQgdGhl IHRydWUgb2Zmc2V0IChmcm9tDQo+IHRoZSBQUFMpIG92ZXIgb25lIGhvdXIgeWllbGRzIHRoZSBm b2xsb3dpbmcgc3RhdGlzdGljcy4NCj4gDQo+ID4gDQo+ID4gwqDCoMKgwqDCoMKgwqB8wqDCoMKg RXN0LiBCZWZvcmUgfMKgwqDCoMKgRXN0LiBBZnRlciB8wqDCoMKgVHJ1ZSBCZWZvcmUgfMKgwqDC oMKgVHJ1ZQ0KPiA+IEFmdGVyIHwNCj4gPiAtLS0tLS0tLSstLS0tLS0tLS0tLS0tLS0rLS0tLS0t LS0tLS0tLS0tKy0tLS0tLS0tLS0tLS0tLSstLS0tLS0tLQ0KPiA+IC0tLS0tLS18DQo+ID4gbWlu wqDCoMKgwqB8IC01LjIwMDAwMGUrMDEgfCAtMS42MDAwMDBlKzAxIHwgLTMuMTAwMDAwZSswMSB8 DQo+ID4gLTEuMDAwMDAwZSswMCB8DQo+ID4gbWF4wqDCoMKgwqB8ICs1LjcwMDAwMGUrMDEgfCAr Mi41MDAwMDBlKzAxIHwgKzguNTAwMDAwZSswMSB8DQo+ID4gKzQuMDAwMDAwZSswMSB8DQo+ID4g cGstcGs6IHwgKzEuMDkwMDAwZSswMiB8ICs0LjEwMDAwMGUrMDEgfCArMS4xNjAwMDBlKzAyIHwN Cj4gPiArNC4xMDAwMDBlKzAxIHwNCj4gPiBtZWFuwqDCoMKgfCArNi40NzIyMjJlLTAyIHwgKzEu Mjc3Nzc4ZS0wMiB8ICsyLjQyMjA4M2UrMDEgfA0KPiA+ICsxLjgyNjA4M2UrMDEgfA0KPiA+IHN0 ZGRldiB8ICsxLjE1ODAwNmUrMDEgfCArNC41ODE5ODJlKzAwIHwgKzEuMjA3NzA4ZSswMSB8DQo+ ID4gKzQuOTgxNDM1ZSswMCB8DQo+IA0KPiBIZXJlIHRoZSBudW1iZXJzIGluIHVuaXRzIG9mIG5h bm9zZWNvbmRzLCBhbmQgdGhlIH4yMCBuYW5vc2Vjb25kIFBQUw0KPiBvZmZzZXQgaXMgZHVlIHRv IGlucHV0L291dHB1dCBkZWxheXMgb24gdGhlIGkyMTAncyBleHRlcm5hbCBpbnRlcmZhY2UNCj4g bG9naWMuDQo+IA0KPiBXaXRoIHRoZSBzZXJpZXMgYXBwbGllZCwgYm90aCB0aGUgcGVhayB0byBw ZWFrIGVycm9yIGFuZCB0aGUgc3RhbmRhcmQNCj4gZGV2aWF0aW9uIGltcHJvdmUgYnkgYSBmYWN0 b3Igb2YgbW9yZSB0aGFuIHR3by7CoMKgVGhlc2UgdHdvIGdyYXBocw0KPiBzaG93DQo+IHRoZSBp bXByb3ZlbWVudCBuaWNlbHkuDQo+IA0KPiDCoCBodHRwOi8vbGludXhwdHAuc291cmNlZm9yZ2Uu bmV0L2ZpbmUtdHVuaW5nL2ZpbmUtZXN0LnBuZw0KPiANCj4gwqAgaHR0cDovL2xpbnV4cHRwLnNv dXJjZWZvcmdlLm5ldC9maW5lLXR1bmluZy9maW5lLXRydS5wbmcNCj4gDQoNCldvdywgbmljZSEg SSdsbCB0YWtlIGEgbG9vayBhdCB0aGUgYWN0dWFsIHBhdGNoZXMgaW4gYSBmZXcgbWludXRlcywg YnV0DQp0aGlzIGlzIGEgcmVhbGx5IG5pY2UgaW1wcm92ZW1lbnQhDQoNClRoYW5rcywNCkpha2UN Cg0KPiANCj4gVGhhbmtzLA0KPiBSaWNoYXJkDQo+IA0KPiBSaWNoYXJkIENvY2hyYW4gKDMpOg0K PiDCoCBwdHA6IEludHJvZHVjZSBhIGhpZ2ggcmVzb2x1dGlvbiBmcmVxdWVuY3kgYWRqdXN0bWVu dCBtZXRob2QuDQo+IMKgIHB0cDogaWdiOiBVc2UgdGhlIGhpZ2ggcmVzb2x1dGlvbiBmcmVxdWVu Y3kgbWV0aG9kLg0KPiDCoCBwdHA6IGRwODM2NDA6IFVzZSB0aGUgaGlnaCByZXNvbHV0aW9uIGZy ZXF1ZW5jeSBtZXRob2QuDQo+IA0KPiDCoGRyaXZlcnMvbmV0L2V0aGVybmV0L2ludGVsL2lnYi9p Z2JfcHRwLmMgfCAxNiArKysrKysrKy0tLS0tLS0tDQo+IMKgZHJpdmVycy9uZXQvcGh5L2RwODM2 NDAuY8KgwqDCoMKgwqDCoMKgwqDCoMKgwqDCoMKgwqDCoMKgfCAxNCArKysrKysrLS0tLS0tLQ0K PiDCoGRyaXZlcnMvcHRwL3B0cF9jbG9jay5jwqDCoMKgwqDCoMKgwqDCoMKgwqDCoMKgwqDCoMKg wqDCoMKgfMKgwqA1ICsrKystDQo+IMKgaW5jbHVkZS9saW51eC9wdHBfY2xvY2tfa2VybmVsLmjC oMKgwqDCoMKgwqDCoMKgwqB8wqDCoDggKysrKysrKysNCj4gwqA0IGZpbGVzIGNoYW5nZWQsIDI3 IGluc2VydGlvbnMoKyksIDE2IGRlbGV0aW9ucygtKQ0KPiANCg==