From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1762007AbcLPQTE (ORCPT ); Fri, 16 Dec 2016 11:19:04 -0500 Received: from mail-he1eur01on0062.outbound.protection.outlook.com ([104.47.0.62]:54048 "EHLO EUR01-HE1-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1755331AbcLPQTC (ORCPT ); Fri, 16 Dec 2016 11:19:02 -0500 From: Jerry Huang To: Felipe Balbi , "gregkh@linuxfoundation.org" CC: "linux-usb@vger.kernel.org" , "linux-kernel@vger.kernel.org" , Rajesh Bhagat Subject: RE: [PATCH] USB3/DWC3: Enable undefined length INCR burst type Thread-Topic: [PATCH] USB3/DWC3: Enable undefined length INCR burst type Thread-Index: AQHSVSKUGATAu7bkYUajSqFxHuv8nqEJ6HqggABnhwCAAAR90IAAJKoAgABJ+gA= Date: Fri, 16 Dec 2016 16:18:56 +0000 Message-ID: References: <1481619983-4782-1-git-send-email-jerry.huang@nxp.com> <87k2b0fd2z.fsf@linux.intel.com> <87bmwcf69h.fsf@linux.intel.com> In-Reply-To: <87bmwcf69h.fsf@linux.intel.com> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: authentication-results: spf=none (sender IP is ) smtp.mailfrom=jerry.huang@nxp.com; x-originating-ip: [175.20.94.193] x-microsoft-exchange-diagnostics: 1;HE1PR0401MB2329;7:HuDbM7zXv9vLAAEYGg9bWtcJDwLmnp6JZ49bdHrB8ZLper2CfOhNxpPZh+vkYTvjnbYVLsW6hgZTwil16HuBG0M3SkRQs1ojp5U7wD9T3lxtbNSrSS9V8xOnBbot1F/nldJkpAkZMcS08OGHJrYn50t18iHMH9vhUCbUXqEcxzxTlqcEKlsYbsmiy7ES2oTY+u2Zpv5rKi4vrXDBPBT22TuldeOWp4z7mkhjbTOQ1KwZNLCOu3S7Ge9k82W7L+P9ig4awPMxEGcV8f+UFvSt9TLtxpNpQY9AyVatWgXOMpmYkWsosw4RuKUjZlCFuFSoPbdE3XdVjOhdk5ZhVmUDsW+XYJIx6Vitl0/BoAUcd9pvZnDreSGY/vhiBQOTOkdH6Xge2N5R0Un1L8A837dRPIrpjVO47Lnw9fvjDSDR4ejbZqBgT6acbZVerkA1FodsfpZj9Gs72J9Tmb6mCKq1RQ== x-forefront-antispam-report: SFV:SKI;SCL:-1SFV:NSPM;SFS:(10009020)(6009001)(7916002)(39450400003)(39860400002)(39840400002)(39850400002)(39410400002)(377454003)(199003)(189002)(13464003)(5890100001)(122556002)(25786008)(81156014)(8936002)(81166006)(2501003)(6436002)(7696004)(68736007)(74316002)(97736004)(9686002)(5001770100001)(189998001)(229853002)(2900100001)(92566002)(77096006)(38730400001)(6506006)(76576001)(101416001)(93886004)(86362001)(105586002)(66066001)(2950100002)(8676002)(106116001)(106356001)(33656002)(4326007)(76176999)(54356999)(102836003)(2906002)(3660700001)(5660300001)(3846002)(6116002)(7736002)(50986999)(305945005)(3280700002);DIR:OUT;SFP:1101;SCL:1;SRVR:HE1PR0401MB2329;H:DB5PR0401MB1813.eurprd04.prod.outlook.com;FPR:;SPF:None;PTR:InfoNoRecords;A:1;MX:1;LANG:en; x-ms-office365-filtering-correlation-id: fba8b8e5-abc4-429b-0605-08d425cf3c63 x-microsoft-antispam: UriScan:;BCL:0;PCL:0;RULEID:(22001);SRVR:HE1PR0401MB2329; x-microsoft-antispam-prvs: x-exchange-antispam-report-test: UriScan:(9452136761055)(185117386973197); x-exchange-antispam-report-cfa-test: BCL:0;PCL:0;RULEID:(6040375)(601004)(2401047)(5005006)(8121501046)(3002001)(10201501046)(6055026)(6041248)(20161123555025)(20161123560025)(20161123562025)(20161123564025)(6047074)(6072148);SRVR:HE1PR0401MB2329;BCL:0;PCL:0;RULEID:;SRVR:HE1PR0401MB2329; x-forefront-prvs: 01583E185C spamdiagnosticoutput: 1:99 spamdiagnosticmetadata: NSPM Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 X-OriginatorOrg: nxp.com X-MS-Exchange-CrossTenant-originalarrivaltime: 16 Dec 2016 16:18:56.5341 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: 686ea1d3-bc2b-4c6f-a92c-d99c5c301635 X-MS-Exchange-Transport-CrossTenantHeadersStamped: HE1PR0401MB2329 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from quoted-printable to 8bit by mail.home.local id uBGGJ8UV019742 Hi, Balbi, > -----Original Message----- > From: Felipe Balbi [mailto:balbi@kernel.org] > Sent: Friday, December 16, 2016 7:44 PM > To: Jerry Huang ; gregkh@linuxfoundation.org > Cc: linux-usb@vger.kernel.org; linux-kernel@vger.kernel.org; Rajesh Bhagat > > Subject: RE: [PATCH] USB3/DWC3: Enable undefined length INCR burst type > > > Hi, > > Jerry Huang writes: > >> there's no need for that. This patch is in good format. I do have a > >> question, > >> however: how do you know this will work for all users? Burst size is > >> a function of how wide the interconnect where dwc3 is attached to, is. > > So I need to generate one new property in usb node to identify my > platform? > > Well, we probably need a property to be passed, yes. But let's go through it > all first :-) I think "snps,quirk-frame-length-adjustment" is one good reference, which can pass the required value to driver from DTS file. > >> You could very well be degrading performance for some users here. Can > >> you send me the result of the following commands *without* this patch > applied? > >> > >> # mkdir -p /d > >> # mount -t debugfs none /d > >> # cat /d/*dwc3*/regdump > >> > > Below is the regdump: > > root@ls1043ardb:/d/3000000.usb3# cat regdump > > GSBUSCFG0 = 0x00100080 > > so you already have INCR256 here. There's one note in the databook which > just caught my attention. It states the following: > > "Undefined burst length has priority over all other burst lenghts." > > This means that setting both INCR16 and undefined INCR is unnecessary. When bit0 = 1 (Undefined Length INCR Burst Type Enable), which means: 1: INCR (undefined length) burst mode - AHB configurations: HBURST uses SINGLE or INCR of any length less than or equal to the largest-enabled burst length of INCR4/8/16/32/64/128/256. - AXI configurations: ARLEN/AWLEN uses any length less than or equal to the largest-enabled burst length of INCR4/8/16/32/64/128/256. So, after enable undefined length INCR burst and enable INCR16, controller will use less than or equal to 16byte. > Only Undefined INCR will be taken into consideration. Can you check with > your HW engineers what's the largest burst the interconnect is supposed to > support? I will check it with IP designer. > > GSBUSCFG1 = 0x00000700 > > 8 AXI pipelined requests > > > GSNPSID = 0x5533280a > > 2.80a cool :-) > > I'll check these settings on my platform as well and see if there's any setting > which would improve transfer speed. This is a very good idea, btw, but we > need to be careful about how to play with it. > > -- > balbi