From mboxrd@z Thu Jan 1 00:00:00 1970 From: Benjamin Herrenschmidt Date: Fri, 09 Dec 2016 11:40:26 +0000 Subject: Re: [RFC PATCH 0/3] staging: remove fbdev drivers Message-Id: <1481283626.27965.9.camel@kernel.crashing.org> List-Id: References: <1479888193-23908-1-git-send-email-tomi.valkeinen@ti.com> <1481158879.26959.41.camel@kernel.crashing.org> <20161208101005.6ufl3d4qvwprosju@phenom.ffwll.local> <1481232519.26959.49.camel@kernel.crashing.org> In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Dave Airlie Cc: Thomas Petazzoni , Linux Fbdev development list , Teddy Wang , Greg Kroah-Hartman , LKML , dri-devel , Tomi Valkeinen , Sudip Mukherjee , Arnaud Patard On Fri, 2016-12-09 at 10:08 +1000, Dave Airlie wrote: > What are people using fbcon for that needs acceleration, this is where I get > a bit lost. > > It's a console, if you aren't sshing into the machine. > > It's main purpose should just be for gathering oopses and you've a lot better > chance of getting an oops if you don't have some sketchy gpu accel in the way. There are other uses for systems running Linux than being a server or desktop :-) > The acceleration that most of the 2D things provide isn't ever that > great, and shadowing is a lot more effective if done properly. Not with a 400Mhz ARM9 processor on a fairly high res display. In these case basic old things like color expansion for font rendering, bit blits and solid fills for scrolls work beautifully. Anyway I just realized that the ARM side of the AST GPU doesn't have the accel bits at all anyway, only the host side, so I'm back to just a dumb FB. I still want to avoid the copies though. > It's a feature > that kernel ppl obsess over but I don't get a lot of real world feedback, > (booting 9000 scsi nodes with debug on takes a long time was possibly > something I heard once, and I think we resolved). Ben. From mboxrd@z Thu Jan 1 00:00:00 1970 From: Benjamin Herrenschmidt Subject: Re: [RFC PATCH 0/3] staging: remove fbdev drivers Date: Fri, 09 Dec 2016 22:40:26 +1100 Message-ID: <1481283626.27965.9.camel@kernel.crashing.org> References: <1479888193-23908-1-git-send-email-tomi.valkeinen@ti.com> <1481158879.26959.41.camel@kernel.crashing.org> <20161208101005.6ufl3d4qvwprosju@phenom.ffwll.local> <1481232519.26959.49.camel@kernel.crashing.org> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Return-path: Received: from gate.crashing.org (gate.crashing.org [63.228.1.57]) by gabe.freedesktop.org (Postfix) with ESMTPS id 1F22F6E891 for ; Fri, 9 Dec 2016 11:40:48 +0000 (UTC) In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" To: Dave Airlie Cc: Thomas Petazzoni , Linux Fbdev development list , Teddy Wang , Greg Kroah-Hartman , LKML , dri-devel , Tomi Valkeinen , Sudip Mukherjee , Arnaud Patard List-Id: dri-devel@lists.freedesktop.org T24gRnJpLCAyMDE2LTEyLTA5IGF0IDEwOjA4ICsxMDAwLCBEYXZlIEFpcmxpZSB3cm90ZToKPiBX aGF0IGFyZSBwZW9wbGUgdXNpbmcgZmJjb24gZm9yIHRoYXQgbmVlZHMgYWNjZWxlcmF0aW9uLCB0 aGlzIGlzIHdoZXJlIEkgZ2V0Cj4gYSBiaXQgbG9zdC4KPiAKPiBJdCdzIGEgY29uc29sZSwgaWYg eW91IGFyZW4ndCBzc2hpbmcgaW50byB0aGUgbWFjaGluZS4KPiAKPiBJdCdzIG1haW4gcHVycG9z ZSBzaG91bGQganVzdCBiZSBmb3IgZ2F0aGVyaW5nIG9vcHNlcyBhbmQgeW91J3ZlIGEgbG90IGJl dHRlcgo+IGNoYW5jZSBvZiBnZXR0aW5nIGFuIG9vcHMgaWYgeW91IGRvbid0IGhhdmUgc29tZSBz a2V0Y2h5IGdwdSBhY2NlbCBpbiB0aGUgd2F5LgoKVGhlcmUgYXJlIG90aGVyIHVzZXMgZm9yIHN5 c3RlbXMgcnVubmluZyBMaW51eCB0aGFuIGJlaW5nIGEgc2VydmVyIG9yIGRlc2t0b3AgOi0pCgo+ IFRoZSBhY2NlbGVyYXRpb24gdGhhdCBtb3N0IG9mIHRoZSAyRCB0aGluZ3MgcHJvdmlkZSBpc24n dCBldmVyIHRoYXQKPiBncmVhdCwgYW5kIHNoYWRvd2luZyBpcyBhIGxvdCBtb3JlIGVmZmVjdGl2 ZSBpZiBkb25lIHByb3Blcmx5LgoKTm90IHdpdGggYSA0MDBNaHogQVJNOSBwcm9jZXNzb3Igb24g YSBmYWlybHkgaGlnaCByZXMgZGlzcGxheS4gSW4gdGhlc2UKY2FzZSBiYXNpYyBvbGQgdGhpbmdz IGxpa2UgY29sb3IgZXhwYW5zaW9uIGZvciBmb250IHJlbmRlcmluZywgYml0CmJsaXRzIGFuZCBz b2xpZCBmaWxscyBmb3Igc2Nyb2xscyB3b3JrIGJlYXV0aWZ1bGx5LiBBbnl3YXkgSSBqdXN0CnJl YWxpemVkIHRoYXQgdGhlIEFSTSBzaWRlIG9mIHRoZSBBU1QgR1BVIGRvZXNuJ3QgaGF2ZSB0aGUg YWNjZWwgYml0cwphdCBhbGwgYW55d2F5LCBvbmx5IHRoZSBob3N0IHNpZGUsIHNvIEknbSBiYWNr IHRvIGp1c3QgYSBkdW1iIEZCLiBJCnN0aWxsIHdhbnQgdG8gYXZvaWQgdGhlIGNvcGllcyB0aG91 Z2guCgo+ICBJdCdzIGEgZmVhdHVyZQo+IHRoYXQga2VybmVsIHBwbCBvYnNlc3Mgb3ZlciBidXQg SSBkb24ndCBnZXQgYSBsb3Qgb2YgcmVhbCB3b3JsZCBmZWVkYmFjaywKPiAoYm9vdGluZyA5MDAw IHNjc2kgbm9kZXMgd2l0aCBkZWJ1ZyBvbiB0YWtlcyBhIGxvbmcgdGltZSB3YXMgcG9zc2libHkK PiBzb21ldGhpbmcgSSBoZWFyZCBvbmNlLCBhbmQgSSB0aGluayB3ZSByZXNvbHZlZCkuCgpCZW4u Cl9fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fCmRyaS1kZXZl bCBtYWlsaW5nIGxpc3QKZHJpLWRldmVsQGxpc3RzLmZyZWVkZXNrdG9wLm9yZwpodHRwczovL2xp c3RzLmZyZWVkZXNrdG9wLm9yZy9tYWlsbWFuL2xpc3RpbmZvL2RyaS1kZXZlbAo= From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933018AbcLILlG (ORCPT ); Fri, 9 Dec 2016 06:41:06 -0500 Received: from gate.crashing.org ([63.228.1.57]:41922 "EHLO gate.crashing.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932320AbcLILlE (ORCPT ); Fri, 9 Dec 2016 06:41:04 -0500 Message-ID: <1481283626.27965.9.camel@kernel.crashing.org> Subject: Re: [RFC PATCH 0/3] staging: remove fbdev drivers From: Benjamin Herrenschmidt To: Dave Airlie Cc: Daniel Vetter , Thomas Petazzoni , Linux Fbdev development list , Teddy Wang , Greg Kroah-Hartman , LKML , dri-devel , Tomi Valkeinen , Sudip Mukherjee , Arnaud Patard Date: Fri, 09 Dec 2016 22:40:26 +1100 In-Reply-To: References: <1479888193-23908-1-git-send-email-tomi.valkeinen@ti.com> <1481158879.26959.41.camel@kernel.crashing.org> <20161208101005.6ufl3d4qvwprosju@phenom.ffwll.local> <1481232519.26959.49.camel@kernel.crashing.org> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.22.2 (3.22.2-1.fc25) Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 2016-12-09 at 10:08 +1000, Dave Airlie wrote: > What are people using fbcon for that needs acceleration, this is where I get > a bit lost. > > It's a console, if you aren't sshing into the machine. > > It's main purpose should just be for gathering oopses and you've a lot better > chance of getting an oops if you don't have some sketchy gpu accel in the way. There are other uses for systems running Linux than being a server or desktop :-) > The acceleration that most of the 2D things provide isn't ever that > great, and shadowing is a lot more effective if done properly. Not with a 400Mhz ARM9 processor on a fairly high res display. In these case basic old things like color expansion for font rendering, bit blits and solid fills for scrolls work beautifully. Anyway I just realized that the ARM side of the AST GPU doesn't have the accel bits at all anyway, only the host side, so I'm back to just a dumb FB. I still want to avoid the copies though. > It's a feature > that kernel ppl obsess over but I don't get a lot of real world feedback, > (booting 9000 scsi nodes with debug on takes a long time was possibly > something I heard once, and I think we resolved). Ben.