From mboxrd@z Thu Jan 1 00:00:00 1970 From: Daniel Vetter Date: Mon, 28 Sep 2015 12:36:27 +0000 Subject: Re: No more new fbdev drivers, please Message-Id: <20150928123627.GD3383@phenom.ffwll.local> List-Id: References: <5603EC15.9090605@ti.com> <20150924144621.40e26f0a@free-electrons.com> <20150924152312.GV3383@phenom.ffwll.local> <1443425953.19666.6.camel@redhat.com> In-Reply-To: <1443425953.19666.6.camel@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Gerd Hoffmann Cc: Thomas Petazzoni , linux-fbdev , Teddy Wang , Greg Kroah-Hartman , Daniel Vetter , "linux-kernel@vger.kernel.org" , DRI Development , Tomi Valkeinen , Geert Uytterhoeven , Laurent Pinchart , Arnaud Patard , Dave Airlie , Sudip Mukherjee On Mon, Sep 28, 2015 at 09:39:13AM +0200, Gerd Hoffmann wrote: > Hi, > > > As Daniel mentioned, the connector+encoder+crtc combination is one of > > those simplifications that would make sense if more such drivers are > > added. > > Another one is memory management. It's pretty complex because it can > handle _way_ more than what simple drivers need, and the result is > _alot_ of ttm boilerplate in the drivers. ttm is pretty impressive overkill for most simplistic drm drivers. If you just need contiguous framebuffers for display then the cma helpers should take care of pretty much all the boilerplate for you. They have ready-made simple gem and dumb framebuffer mmap support, which is all a basic kms driver needs. -Daniel -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch From mboxrd@z Thu Jan 1 00:00:00 1970 From: Daniel Vetter Subject: Re: No more new fbdev drivers, please Date: Mon, 28 Sep 2015 14:36:27 +0200 Message-ID: <20150928123627.GD3383@phenom.ffwll.local> References: <5603EC15.9090605@ti.com> <20150924144621.40e26f0a@free-electrons.com> <20150924152312.GV3383@phenom.ffwll.local> <1443425953.19666.6.camel@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Return-path: Received: from mail-wi0-f171.google.com (mail-wi0-f171.google.com [209.85.212.171]) by gabe.freedesktop.org (Postfix) with ESMTPS id BB3EC6E9BF for ; Mon, 28 Sep 2015 05:33:34 -0700 (PDT) Received: by wicfx3 with SMTP id fx3so102327175wic.1 for ; Mon, 28 Sep 2015 05:33:33 -0700 (PDT) Content-Disposition: inline In-Reply-To: <1443425953.19666.6.camel@redhat.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" To: Gerd Hoffmann Cc: Thomas Petazzoni , linux-fbdev , Teddy Wang , Greg Kroah-Hartman , Daniel Vetter , "linux-kernel@vger.kernel.org" , DRI Development , Tomi Valkeinen , Geert Uytterhoeven , Laurent Pinchart , Arnaud Patard , Dave Airlie , Sudip Mukherjee List-Id: dri-devel@lists.freedesktop.org T24gTW9uLCBTZXAgMjgsIDIwMTUgYXQgMDk6Mzk6MTNBTSArMDIwMCwgR2VyZCBIb2ZmbWFubiB3 cm90ZToKPiAgIEhpLAo+IAo+ID4gQXMgRGFuaWVsIG1lbnRpb25lZCwgdGhlIGNvbm5lY3Rvcitl bmNvZGVyK2NydGMgY29tYmluYXRpb24gaXMgb25lIG9mCj4gPiB0aG9zZSBzaW1wbGlmaWNhdGlv bnMgdGhhdCB3b3VsZCBtYWtlIHNlbnNlIGlmIG1vcmUgc3VjaCBkcml2ZXJzIGFyZQo+ID4gYWRk ZWQuCj4gCj4gQW5vdGhlciBvbmUgaXMgbWVtb3J5IG1hbmFnZW1lbnQuICBJdCdzIHByZXR0eSBj b21wbGV4IGJlY2F1c2UgaXQgY2FuCj4gaGFuZGxlIF93YXlfIG1vcmUgdGhhbiB3aGF0IHNpbXBs ZSBkcml2ZXJzIG5lZWQsIGFuZCB0aGUgcmVzdWx0IGlzCj4gX2Fsb3RfIG9mIHR0bSBib2lsZXJw bGF0ZSBpbiB0aGUgZHJpdmVycy4KCnR0bSBpcyBwcmV0dHkgaW1wcmVzc2l2ZSBvdmVya2lsbCBm b3IgbW9zdCBzaW1wbGlzdGljIGRybSBkcml2ZXJzLiBJZiB5b3UKanVzdCBuZWVkIGNvbnRpZ3Vv dXMgZnJhbWVidWZmZXJzIGZvciBkaXNwbGF5IHRoZW4gdGhlIGNtYSBoZWxwZXJzIHNob3VsZAp0 YWtlIGNhcmUgb2YgcHJldHR5IG11Y2ggYWxsIHRoZSBib2lsZXJwbGF0ZSBmb3IgeW91LiBUaGV5 IGhhdmUgcmVhZHktbWFkZQpzaW1wbGUgZ2VtIGFuZCBkdW1iIGZyYW1lYnVmZmVyIG1tYXAgc3Vw cG9ydCwgd2hpY2ggaXMgYWxsIGEgYmFzaWMga21zCmRyaXZlciBuZWVkcy4KLURhbmllbAotLSAK RGFuaWVsIFZldHRlcgpTb2Z0d2FyZSBFbmdpbmVlciwgSW50ZWwgQ29ycG9yYXRpb24KaHR0cDov L2Jsb2cuZmZ3bGwuY2gKX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19f X19fX18KZHJpLWRldmVsIG1haWxpbmcgbGlzdApkcmktZGV2ZWxAbGlzdHMuZnJlZWRlc2t0b3Au b3JnCmh0dHA6Ly9saXN0cy5mcmVlZGVza3RvcC5vcmcvbWFpbG1hbi9saXN0aW5mby9kcmktZGV2 ZWwK From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757452AbbI1Mdi (ORCPT ); Mon, 28 Sep 2015 08:33:38 -0400 Received: from mail-wi0-f172.google.com ([209.85.212.172]:35317 "EHLO mail-wi0-f172.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757269AbbI1Mde (ORCPT ); Mon, 28 Sep 2015 08:33:34 -0400 Date: Mon, 28 Sep 2015 14:36:27 +0200 From: Daniel Vetter To: Gerd Hoffmann Cc: David Herrmann , Geert Uytterhoeven , Thomas Petazzoni , linux-fbdev , Teddy Wang , Daniel Vetter , "linux-kernel@vger.kernel.org" , DRI Development , Arnaud Patard , Tomi Valkeinen , Laurent Pinchart , Greg Kroah-Hartman , Dave Airlie , Sudip Mukherjee Subject: Re: No more new fbdev drivers, please Message-ID: <20150928123627.GD3383@phenom.ffwll.local> Mail-Followup-To: Gerd Hoffmann , David Herrmann , Geert Uytterhoeven , Thomas Petazzoni , linux-fbdev , Teddy Wang , "linux-kernel@vger.kernel.org" , DRI Development , Arnaud Patard , Tomi Valkeinen , Laurent Pinchart , Greg Kroah-Hartman , Dave Airlie , Sudip Mukherjee References: <5603EC15.9090605@ti.com> <20150924144621.40e26f0a@free-electrons.com> <20150924152312.GV3383@phenom.ffwll.local> <1443425953.19666.6.camel@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1443425953.19666.6.camel@redhat.com> X-Operating-System: Linux phenom 4.1.0-2-amd64 User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Sep 28, 2015 at 09:39:13AM +0200, Gerd Hoffmann wrote: > Hi, > > > As Daniel mentioned, the connector+encoder+crtc combination is one of > > those simplifications that would make sense if more such drivers are > > added. > > Another one is memory management. It's pretty complex because it can > handle _way_ more than what simple drivers need, and the result is > _alot_ of ttm boilerplate in the drivers. ttm is pretty impressive overkill for most simplistic drm drivers. If you just need contiguous framebuffers for display then the cma helpers should take care of pretty much all the boilerplate for you. They have ready-made simple gem and dumb framebuffer mmap support, which is all a basic kms driver needs. -Daniel -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch