From mboxrd@z Thu Jan 1 00:00:00 1970 From: Boris Brezillon Subject: Re: [PATCH] drm/fb-helper: Blacklist writeback when adding connectors to fbdev Date: Thu, 15 Nov 2018 17:42:39 +0100 Message-ID: <20181115174239.773b71e9@bbrezillon> References: <20181115163248.21168-1-paul.kocialkowski@bootlin.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Return-path: Received: from mail.bootlin.com (mail.bootlin.com [62.4.15.54]) by gabe.freedesktop.org (Postfix) with ESMTP id F024A6E113 for ; Thu, 15 Nov 2018 16:42:57 +0000 (UTC) In-Reply-To: <20181115163248.21168-1-paul.kocialkowski@bootlin.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" To: Paul Kocialkowski Cc: Maxime Ripard , linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, David Airlie , Thomas Petazzoni , Sean Paul List-Id: dri-devel@lists.freedesktop.org T24gVGh1LCAxNSBOb3YgMjAxOCAxNzozMjo0OCArMDEwMApQYXVsIEtvY2lhbGtvd3NraSA8cGF1 bC5rb2NpYWxrb3dza2lAYm9vdGxpbi5jb20+IHdyb3RlOgoKPiBXcml0ZWJhY2sgY29ubmVjdG9y cyBkbyBub3QgcHJvZHVjZSBhbnkgb24tc2NyZWVuIG91dHB1dCBhbmQgcmVxdWlyZQo+IHNwZWNp YWwgY2FyZSBmb3IgdXNlLiBTdWNoIGNvbm5lY3RvcnMgYXJlIGhpZGRlbiBmcm9tIGVudW1lcmF0 aW9uIGluCj4gRFJNIHJlc291cmNlcyBieSBkZWZhdWx0LCBidXQgdGhleSBhcmUgc3RpbGwgcGlj a2VkLXVwIGJ5IGZiZGV2Lgo+IFRoaXMgbWFrZXMgcmF0aGVyIGxpdHRsZSBzZW5zZSBzaW5jZSBm YmRldiBpcyBub3QgcmVhbGx5IGFkYXB0ZWQgZm9yCj4gZGVhbGluZyB3aXRoIHdyaXRlYmFjay4K PiAKPiBNb3Jlb3ZlciwgdGhpcyBpcyBhbHNvIGEgc291cmNlIG9mIGlzc3VlcyB3aGVuIHVzZXJz cGFjZSBkaXNhYmxlcyB0aGUKPiBDUlRDIChhbmQgYXNzb2NpYXRlZCBwbGFuZSkgd2l0aG91dCBk ZXRhY2hpbmcgdGhlIENSVEMgZnJvbSB0aGUKPiBjb25uZWN0b3IgKHdoaWNoIGlzIGhpZGRlbiBi eSBkZWZhdWx0KS4gSW4gdGhpcyBjYXNlLCB0aGUgY29ubmVjdG9yIGlzCj4gc3RpbGwgdXNpbmcg dGhlIENSVEMsIGxlYWRpbmcgdG8gYW0gImVuYWJsZWQvY29ubmVjdG9ycyBtaXNtYXRjaCIgYW5k CgoJCQkJICAgXmFuCgo+IGV2ZW50dWFsbHkgdGhlIGZhaWx1cmUgb2YgdGhlIGFzc29jaWF0ZWQg YXRvbWljIGNvbW1pdC4gVGhpcyBzaXR1YXRpb24KPiBoYXBwZW5zIHdpdGggVkM0IHRlc3Rpbmcg dW5kZXIgSUdUIEdQVSBUb29scy4KPiAKPiBGaWx0ZXIgb3V0IHdyaXRlYmFjayBjb25uZWN0b3Jz IGluIHRoZSBmYmRldiBoZWxwZXIgdG8gc29sdmUgdGhpcy4KPiAKPiBTaWduZWQtb2ZmLWJ5OiBQ YXVsIEtvY2lhbGtvd3NraSA8cGF1bC5rb2NpYWxrb3dza2lAYm9vdGxpbi5jb20+CgpSZXZpZXdl ZC1ieTogQm9yaXMgQnJlemlsbG9uIDxib3Jpcy5icmV6aWxsb25AYm9vdGxpbi5jb20+Cgo+IC0t LQo+ICBkcml2ZXJzL2dwdS9kcm0vZHJtX2ZiX2hlbHBlci5jIHwgMyArKysKPiAgMSBmaWxlIGNo YW5nZWQsIDMgaW5zZXJ0aW9ucygrKQo+IAo+IGRpZmYgLS1naXQgYS9kcml2ZXJzL2dwdS9kcm0v ZHJtX2ZiX2hlbHBlci5jIGIvZHJpdmVycy9ncHUvZHJtL2RybV9mYl9oZWxwZXIuYwo+IGluZGV4 IGE1MDJmM2U1MTlmZC4uZGQ4NTJhMjVkMzc1IDEwMDY0NAo+IC0tLSBhL2RyaXZlcnMvZ3B1L2Ry bS9kcm1fZmJfaGVscGVyLmMKPiArKysgYi9kcml2ZXJzL2dwdS9kcm0vZHJtX2ZiX2hlbHBlci5j Cj4gQEAgLTIxOSw2ICsyMTksOSBAQCBpbnQgZHJtX2ZiX2hlbHBlcl9zaW5nbGVfYWRkX2FsbF9j b25uZWN0b3JzKHN0cnVjdCBkcm1fZmJfaGVscGVyICpmYl9oZWxwZXIpCj4gIAltdXRleF9sb2Nr KCZmYl9oZWxwZXItPmxvY2spOwo+ICAJZHJtX2Nvbm5lY3Rvcl9saXN0X2l0ZXJfYmVnaW4oZGV2 LCAmY29ubl9pdGVyKTsKPiAgCWRybV9mb3JfZWFjaF9jb25uZWN0b3JfaXRlcihjb25uZWN0b3Is ICZjb25uX2l0ZXIpIHsKPiArCQlpZiAoY29ubmVjdG9yLT5jb25uZWN0b3JfdHlwZSA9PSBEUk1f TU9ERV9DT05ORUNUT1JfV1JJVEVCQUNLKQo+ICsJCQljb250aW51ZTsKPiArCj4gIAkJcmV0ID0g X19kcm1fZmJfaGVscGVyX2FkZF9vbmVfY29ubmVjdG9yKGZiX2hlbHBlciwgY29ubmVjdG9yKTsK PiAgCQlpZiAocmV0KQo+ICAJCQlnb3RvIGZhaWw7CgpfX19fX19fX19fX19fX19fX19fX19fX19f X19fX19fX19fX19fX19fX19fX19fXwpkcmktZGV2ZWwgbWFpbGluZyBsaXN0CmRyaS1kZXZlbEBs aXN0cy5mcmVlZGVza3RvcC5vcmcKaHR0cHM6Ly9saXN0cy5mcmVlZGVza3RvcC5vcmcvbWFpbG1h bi9saXN0aW5mby9kcmktZGV2ZWwK From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E089EC43441 for ; Thu, 15 Nov 2018 16:43:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9F1C721582 for ; Thu, 15 Nov 2018 16:43:01 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9F1C721582 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=bootlin.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388505AbeKPCvc (ORCPT ); Thu, 15 Nov 2018 21:51:32 -0500 Received: from mail.bootlin.com ([62.4.15.54]:48971 "EHLO mail.bootlin.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387839AbeKPCvc (ORCPT ); Thu, 15 Nov 2018 21:51:32 -0500 Received: by mail.bootlin.com (Postfix, from userid 110) id 4803C207AD; Thu, 15 Nov 2018 17:42:57 +0100 (CET) Received: from bbrezillon (aaubervilliers-681-1-13-146.w90-88.abo.wanadoo.fr [90.88.134.146]) by mail.bootlin.com (Postfix) with ESMTPSA id 849262074D; Thu, 15 Nov 2018 17:42:39 +0100 (CET) Date: Thu, 15 Nov 2018 17:42:39 +0100 From: Boris Brezillon To: Paul Kocialkowski Cc: dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, Maarten Lankhorst , Maxime Ripard , Sean Paul , David Airlie , Thomas Petazzoni , Eric Anholt Subject: Re: [PATCH] drm/fb-helper: Blacklist writeback when adding connectors to fbdev Message-ID: <20181115174239.773b71e9@bbrezillon> In-Reply-To: <20181115163248.21168-1-paul.kocialkowski@bootlin.com> References: <20181115163248.21168-1-paul.kocialkowski@bootlin.com> X-Mailer: Claws Mail 3.16.0 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 15 Nov 2018 17:32:48 +0100 Paul Kocialkowski wrote: > Writeback connectors do not produce any on-screen output and require > special care for use. Such connectors are hidden from enumeration in > DRM resources by default, but they are still picked-up by fbdev. > This makes rather little sense since fbdev is not really adapted for > dealing with writeback. > > Moreover, this is also a source of issues when userspace disables the > CRTC (and associated plane) without detaching the CRTC from the > connector (which is hidden by default). In this case, the connector is > still using the CRTC, leading to am "enabled/connectors mismatch" and ^an > eventually the failure of the associated atomic commit. This situation > happens with VC4 testing under IGT GPU Tools. > > Filter out writeback connectors in the fbdev helper to solve this. > > Signed-off-by: Paul Kocialkowski Reviewed-by: Boris Brezillon > --- > drivers/gpu/drm/drm_fb_helper.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c > index a502f3e519fd..dd852a25d375 100644 > --- a/drivers/gpu/drm/drm_fb_helper.c > +++ b/drivers/gpu/drm/drm_fb_helper.c > @@ -219,6 +219,9 @@ int drm_fb_helper_single_add_all_connectors(struct drm_fb_helper *fb_helper) > mutex_lock(&fb_helper->lock); > drm_connector_list_iter_begin(dev, &conn_iter); > drm_for_each_connector_iter(connector, &conn_iter) { > + if (connector->connector_type == DRM_MODE_CONNECTOR_WRITEBACK) > + continue; > + > ret = __drm_fb_helper_add_one_connector(fb_helper, connector); > if (ret) > goto fail;