Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755494AbdGKIuB (ORCPT ); Tue, 11 Jul 2017 04:50:01 -0400 Received: from gagarine.paulk.fr ([109.190.93.129]:62594 "EHLO gagarine.paulk.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755262AbdGKIt7 (ORCPT ); Tue, 11 Jul 2017 04:49:59 -0400 Message-ID: <1499762987.1340.10.camel@paulk.fr> Subject: Re: [PATCH] gpu: host1x: Free the IOMMU domain when there is no device to attach From: Paul Kocialkowski To: linux-arm-kernel@lists.infradead.org, linux-tegra@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Jonathan Hunter , Stephen Warren , Mikko Perttunen , Thierry Reding Date: Tue, 11 Jul 2017 11:49:47 +0300 In-Reply-To: <20170710193305.5987-1-contact@paulk.fr> References: <20170710193305.5987-1-contact@paulk.fr> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.24.3 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 Content-Length: 1685 Lines: 53 On Mon, 2017-07-10 at 21:33 +0200, Paul Kocialkowski wrote: > When there is no device to attach to the IOMMU domain, as may be the > case when the device-tree does not contain the proper iommu node, it > is > best to keep going without IOMMU support rather than failing. > This allows the driver to probe and function instead of taking down > all of the tegra drm driver, leading to missing display support. Fixes: 404bfb78daf3 ("gpu: host1x: Add IOMMU support") > Signed-off-by: Paul Kocialkowski > --- > drivers/gpu/host1x/dev.c | 8 +++++++- > 1 file changed, 7 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpu/host1x/dev.c b/drivers/gpu/host1x/dev.c > index ac65f52850a6..f296738d0de8 100644 > --- a/drivers/gpu/host1x/dev.c > +++ b/drivers/gpu/host1x/dev.c > @@ -186,8 +186,13 @@ static int host1x_probe(struct platform_device > *pdev) > return -ENOMEM; > > err = iommu_attach_device(host->domain, &pdev->dev); > - if (err) > + if (err == -ENODEV) { > + iommu_domain_free(host->domain); > + host->domain = NULL; > + goto iommu_skip; > + } else if (err) { > goto fail_free_domain; > + } > > geometry = &host->domain->geometry; > > @@ -198,6 +203,7 @@ static int host1x_probe(struct platform_device > *pdev) > host->iova_end = geometry->aperture_end; > } > > +iommu_skip: > err = host1x_channel_list_init(host); > if (err) { > dev_err(&pdev->dev, "failed to initialize channel > list\n"); -- Paul Kocialkowski, developer of free digital technology and hardware support Website: https://www.paulk.fr/ Coding blog: https://code.paulk.fr/ Git repositories: https://git.paulk.fr/ https://git.code.paulk.fr/