Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752108AbdFNSjG (ORCPT ); Wed, 14 Jun 2017 14:39:06 -0400 Received: from mail-wr0-f170.google.com ([209.85.128.170]:34910 "EHLO mail-wr0-f170.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751760AbdFNSjD (ORCPT ); Wed, 14 Jun 2017 14:39:03 -0400 From: Arun Parameswaran Subject: Re: [PATCH v1 1/2] dt-binding: ptp: add bindings document for dte based ptp clock To: Ray Jui , Richard Cochran Cc: Rob Herring , Mark Rutland , devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, bcm-kernel-feedback-list@broadcom.com References: <1497299161-6458-1-git-send-email-arun.parameswaran@broadcom.com> <1497299161-6458-2-git-send-email-arun.parameswaran@broadcom.com> <20170613050947.GA1684@localhost.localdomain> Message-ID: Date: Wed, 14 Jun 2017 11:39:17 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.1.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1258 Lines: 40 On 17-06-14 11:18 AM, Ray Jui wrote: > > > On 6/13/17 10:46 AM, Arun Parameswaran wrote: >> >> Hi Richard, >> >> On 17-06-12 10:09 PM, Richard Cochran wrote: >>> On Mon, Jun 12, 2017 at 01:26:00PM -0700, Arun Parameswaran wrote: >>>> +Example: >>>> + >>>> +ptp_dte: ptp_dte@180af650 { >>>> + compatible = "brcm,ptp-dte"; >>>> + reg = <0x180af650 0x10>; >>>> + status = "okay"; >>>> +}; >>> This patch set looks okay, as far as it goes, but how does one >>> actually use the clock? >>> >>> How does one connect this node to an Ethernet MAC, for example? >> In some of the SoC's, the DTE's NCO is synced in hardware with the Ethernet's >> 1588 Shim NCO (used for time-stamping the packets). We are working on getting >> all the future SoC's synced this way (for Ethernet). >> > > So apparently you do not need any phandle based DT binding defined for > the connection between the Ethernet device node and the PTP device node? > Correct. This driver doesn't need any phandle. The Ethernet driver, in SoC's where the hardware link is not available, might need the phandle to this driver. >> In other scenarios, we use an user-space app to perform the sync based on >> time-stamps from external hardware sources like the Wi-Fi. >>> Thanks, >>> Richard >>