Received-SPF: pass (google.com: domain of linux-wireless-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
From:   "Stern, Avraham" <avraham.stern@intel.com>
To:     Richard Cochran <richardcochran@gmail.com>
CC:     "Greenman, Gregory" <gregory.greenman@intel.com>,
        "kuba@kernel.org" <kuba@kernel.org>,
        "linux-wireless@vger.kernel.org" <linux-wireless@vger.kernel.org>,
        "johannes@sipsolutions.net" <johannes@sipsolutions.net>,
        "netdev@vger.kernel.org" <netdev@vger.kernel.org>
Subject: RE: pull-request: wireless-next-2023-03-30
Thread-Topic: pull-request: wireless-next-2023-03-30
Thread-Index: AQHZbbjNzP9gzb4bwEuw1qGhSN1B8K8xGe8AgAJ/PgCABVt224ACIUqAgAA5hgCAAFSOMA==
Date:   Tue, 25 Apr 2023 07:03:50 +0000
Message-ID: <SN7PR11MB6996324EBF976C507D382C3AFF649@SN7PR11MB6996.namprd11.prod.outlook.com>
References: <20230330205612.921134-1-johannes@sipsolutions.net>
 <20230331000648.543f2a54@kernel.org> <ZCtXGpqnCUL58Xzu@localhost>
 <ZDd4Hg6bEv22Pxi9@hoboy.vegasvil.org>
 <ccc046c7e7db68915447c05726dd90654a7a8ffc.camel@intel.com>
 <ZEC08ivL3ngWFQBH@hoboy.vegasvil.org>
 <SN7PR11MB6996329FFC32ECCBE4509531FF669@SN7PR11MB6996.namprd11.prod.outlook.com>
 <ZEb81aNUlmpKsJ6C@hoboy.vegasvil.org> <ZEctFm4ZreZ5ToP9@hoboy.vegasvil.org>
In-Reply-To: <ZEctFm4ZreZ5ToP9@hoboy.vegasvil.org>
Accept-Language: en-US
Content-Language: en-US
x-ms-exchange-antispam-messagedata-chunkcount: 1
x-ms-exchange-antispam-messagedata-0: =?us-ascii?Q?ti/TCkXxqsMB+y3m/UpneGMjw/ZNsZXYE9QnOAmzaIRGqIYU+9HCInL9R8Uy?=
 =?us-ascii?Q?erGJ6/S9eGnQhVXd4xvsZyKjdfhvYIfz4MnfUq5caBbnewGm7jcgvQn1lbEZ?=
 =?us-ascii?Q?ItusBZzdlssKKtbyG5EVrkagxj99kEcGyjX78VFfo7O/SrcDuNCQ0MGypRof?=
 =?us-ascii?Q?5A2cg63tELKmKM5vVq91MYQpGV+imM6suTHtuAmJB/BE92CCf8KF9Ysq5Vgh?=
 =?us-ascii?Q?l9s67787PSO1DrfRhw61/59MuHf4E4GhIho9OvONLvcujybr89d2UM+db0sF?=
 =?us-ascii?Q?h8Ov+74aEZn/EUlJD7Ao5ybQAYY+R/xvw3czi26CwUnQtw0NWHt7cN3Cm9B+?=
 =?us-ascii?Q?P8cwDopE0ZRAip/PKiKHgmv5J9rGGI11bzx988Iy6EXhBaa7llCu0HzveW+8?=
 =?us-ascii?Q?0Fe2li4MU2MojD2dUlB7Wd46cudVItIslfKWDtyPHpvFTNBWoEAYVCCKY5Zk?=
 =?us-ascii?Q?/CkPt3pui463A4sg6Rzr4CJ9/QhwUmWb679fZ5C53Uv7mTjD7EeNnU/ppIXC?=
 =?us-ascii?Q?KNyT5LD88iNLkk7aqvaBnF6NRbFZXLbDZcAewPsMDFL0ne6FGzgWjysI8D22?=
 =?us-ascii?Q?gIkx49luojC5Jdi7zsd//geW+Ph6eoDTKJzKuG8sptQa/k5+G3KX7AZvyxcF?=
 =?us-ascii?Q?hGrKAA8o3S6OubsKW6dqvbhG0Ecg9hkOzNe/ARLdKH0MfrR87MdPGPU0l0hx?=
 =?us-ascii?Q?53T25L15Fk/24KKwtJHAizXzja9hauzLmabtX94fSCjPUm3X74hDNWybV1EF?=
 =?us-ascii?Q?0P3fsuv73YT5r2YbB/o3HtYmUQzPD0ugtxaONYNZRotQXJyLrWqbGpxNIayg?=
 =?us-ascii?Q?2FVOjBx7p+Xb+x2xP3n9atvaf1h1E0Uin35Vbav9QLDoEB7O0hySRXbdj5Q+?=
 =?us-ascii?Q?v7gP2ljj5s1i9Hly4rgTNVZxF3dTYwdkCfHE0mz5S18pGrfO595vyhWY8lUy?=
 =?us-ascii?Q?rd9Vze8MIAr2IQqx6AnTjRoAP2AP4ltb/DOleHMThdjJh8u4TFKynUFnKyMU?=
 =?us-ascii?Q?YlHIswDpdlwx9WUvlnxitfA/Qqi+9CpmA/R+D4xPw8/2pIr4QkC/5Gor5HRy?=
 =?us-ascii?Q?xL+TeNaDiVHz3Wnv/aUuR8qp/Gd51AAtReTwOuRbZC3IKR8myl/8BF7TeU7m?=
 =?us-ascii?Q?Sy2pCxT3D0KZhT7IIQbJUQQFExJIrnFzEkV19bfzYv9MaXhqTrRdB63VW7M8?=
 =?us-ascii?Q?gBA/ep7C31Jm9Uzc9rOcWp7OrzQ31MESqKzPnYdXJO7U+2oPuE2Po3dKwAnh?=
 =?us-ascii?Q?orSqmVpxBtXjr4ba/OsXPSNL2VR47Mei5gPeaH1vf7PVTZZvdm+mstwjo40q?=
 =?us-ascii?Q?hiWsltYxcVwHnsXVleOSTuMhYae7MaIObzcVeL5316qFYk3Nitn/Y/6/vE3s?=
 =?us-ascii?Q?Tk70C/XWJ81+yOFSRqF3gMlcjpHAhJ6yv/x/l2+Em8tbWQgTh1Rw/PfYFLFn?=
 =?us-ascii?Q?TuPT4RO1hugAlidEUS0zCMpriYvODb393o5+7Fq57oPbMAtJMYt90tYriD8P?=
 =?us-ascii?Q?Le/gUFx+5j35wvNiRXENnhqB78Knu5dQRdZeIuCJLOZ8b10akk91PtEoBqp5?=
 =?us-ascii?Q?bN4aKM1y+D+m/+AjspY9pdjGNCjJmjiJOJcLDkKh?=
Content-Type: text/plain; charset="us-ascii"
MIME-Version: 1.0
X-MS-Exchange-CrossTenant-AuthAs: Internal
X-MS-Exchange-CrossTenant-AuthSource: SN7PR11MB6996.namprd11.prod.outlook.com
X-MS-Exchange-CrossTenant-Network-Message-Id: 0d113366-c9a9-4909-6559-08db455b393c
X-MS-Exchange-CrossTenant-originalarrivaltime: 25 Apr 2023 07:03:50.7170
 (UTC)
X-MS-Exchange-CrossTenant-fromentityheader: Hosted
X-MS-Exchange-CrossTenant-id: 46c98d88-e344-4ed4-8496-4ed7712e255d
X-MS-Exchange-CrossTenant-mailboxtype: HOSTED
X-MS-Exchange-CrossTenant-userprincipalname: MEvFTCfghItlMEIPmJikHbKZ/d9RvXBK/1aIfMLB8o55ytij08OBNqD1I5IHuZa58W3lQeGsO9A7pvCNPyqgXw==
X-MS-Exchange-Transport-CrossTenantHeadersStamped: MN0PR11MB5961
X-OriginatorOrg: intel.com
Content-Transfer-Encoding: quoted-printable
X-Spam-Status: No, score=-4.6 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH,
        DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_MED,
        RCVD_IN_MSPIKE_H3,RCVD_IN_MSPIKE_WL,SPF_HELO_NONE,SPF_NONE,
        T_SCC_BODY_TEXT_LINE,URIBL_BLOCKED autolearn=ham autolearn_force=no
        version=3.4.6
X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on
        lindbergh.monkeyblade.net
Precedence: bulk
List-ID: <linux-wireless.vger.kernel.org>
X-Mailing-List: linux-wireless@vger.kernel.org


> On Mon, Apr 24, 2023 at 03:04:07PM -0700, Richard Cochran wrote:
> > On Sun, Apr 23, 2023 at 01:33:19PM +0000, Stern, Avraham wrote:

> > So obviously for ptp4l to support time sync over wifi, it will need =

> > to implement the FTM protocol (sending FTM frames via nl80211
> > socket) and use the kernel APIs added here

> "obviously" ?

> In the past, I made quite some thougts about how to best implement PTP ov=
er Wifi.  I may have even written something about it.

Sorry, of course nothing goes into ptp4l without your approval.
I was not aware about what you previously wrote on this subject.

> In any case, "implement the FTM protocol (sending FTM frames via
> nl80211 socket)" was definitely NOT one of the approaches.

My understanding was that 1588-2019 and 8021AS-2020 mandate the usage of TM=
/FTM for PTP over wifi. Since FTM offload (as it is today) is not reporting=
 the raw timestamps (only the calculated range) and also doesn't support ad=
ding the needed vendor IEs, it didn't seem to fit.
Can you please explain what I am missing?

> Wouldn't it have great to start a discussion before plowing ahead and hac=
king something into the kernel?

> Oh well.

Having the timestamps of the frames seemed like a basic capability that use=
rspace will need to implement ptp over wifi, regardless of the selected app=
roach.
Apparently you had other ways in mind, so I would love to have that discuss=
ion and hear about it.  =


Thanks,
Avi.
---------------------------------------------------------------------
A member of the Intel Corporation group of companies

This e-mail and any attachments may contain confidential material for
the sole use of the intended recipient(s). Any review or distribution
by others is strictly prohibited. If you are not the intended
recipient, please contact the sender and delete all copies.