From mboxrd@z Thu Jan 1 00:00:00 1970 From: Manasi Navare Subject: Re: RMW considered harmful (was: Re: [PATCH 2/2] drm/i915/icl: Enable TRANSCODER PORT SYNC for tiled displays across separate ports) Date: Thu, 28 Mar 2019 08:40:08 -0700 Message-ID: <20190328154008.GA22377@intel.com> References: <20190322015939.23189-2-manasi.d.navare@intel.com> <87va0bb6ce.fsf@intel.com> <20190322131603.GR3888@intel.com> <20190322175801.GB27582@intel.com> <20190322180949.GI3888@intel.com> <20190322184421.GA28038@intel.com> <20190322184656.GK3888@intel.com> <874l7ubtfi.fsf@intel.com> <20190322194008.GB28038@intel.com> <87lg0z2w73.fsf@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Return-path: Received: from mga07.intel.com (mga07.intel.com [134.134.136.100]) by gabe.freedesktop.org (Postfix) with ESMTPS id 9C4D46E45F for ; Thu, 28 Mar 2019 15:38:01 +0000 (UTC) Content-Disposition: inline In-Reply-To: <87lg0z2w73.fsf@intel.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" To: Jani Nikula Cc: Daniel Vetter , intel-gfx@lists.freedesktop.org List-Id: intel-gfx@lists.freedesktop.org T24gVGh1LCBNYXIgMjgsIDIwMTkgYXQgMTE6MTg6NTZBTSArMDIwMCwgSmFuaSBOaWt1bGEgd3Jv dGU6Cj4gT24gRnJpLCAyMiBNYXIgMjAxOSwgTWFuYXNpIE5hdmFyZSA8bWFuYXNpLmQubmF2YXJl QGludGVsLmNvbT4gd3JvdGU6Cj4gPiBPbiBGcmksIE1hciAyMiwgMjAxOSBhdCAwOToyODowMVBN ICswMjAwLCBKYW5pIE5pa3VsYSB3cm90ZToKPiA+PiBPbiBGcmksIDIyIE1hciAyMDE5LCBWaWxs ZSBTeXJqw6Rsw6QgPHZpbGxlLnN5cmphbGFAbGludXguaW50ZWwuY29tPiB3cm90ZToKPiA+PiA+ IE9uIEZyaSwgTWFyIDIyLCAyMDE5IGF0IDExOjQ0OjIxQU0gLTA3MDAsIE1hbmFzaSBOYXZhcmUg d3JvdGU6Cj4gPj4gPj4gT24gRnJpLCBNYXIgMjIsIDIwMTkgYXQgMDg6MDk6NTBQTSArMDIwMCwg VmlsbGUgU3lyasOkbMOkIHdyb3RlOgo+ID4+ID4+ID4gSW4gdGhhdCBjYXNlIHRoZXJlIGlzIG5v IHBvaW50IGluIGRvaW5nIGEgcm13Lgo+ID4+ID4+IAo+ID4+ID4+IEJ1dCBpc250IGl0IGFsd2F5 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