From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752982AbaHSMbI (ORCPT ); Tue, 19 Aug 2014 08:31:08 -0400 Received: from cantor2.suse.de ([195.135.220.15]:50063 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751492AbaHSMbG (ORCPT ); Tue, 19 Aug 2014 08:31:06 -0400 Message-ID: <53F34383.30100@suse.de> Date: Tue, 19 Aug 2014 14:30:59 +0200 From: =?UTF-8?B?QW5kcmVhcyBGw6RyYmVy?= Organization: SUSE LINUX Products GmbH User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.7.0 MIME-Version: 1.0 To: Marek Szyprowski , Inki Dae CC: Joerg Roedel , iommu@lists.linux-foundation.org, linux-samsung-soc@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linaro-mm-sig@lists.linaro.org, Arnd Bergmann , Shaik Ameer Basha , Cho KyongHo , Thierry Reding , Olof Johansson , Laurent Pinchart , Rob Herring , Greg Kroah-Hartman , "Rafael J. Wysocki" , Kukjin Kim , Sylwester Nawrocki , Tomasz Figa , Kyungmin Park , Ajay Kumar Subject: Re: [PATCH 00/29] Exynos SYSMMU (IOMMU) integration with DT and DMA-mapping subsystem References: <1407235677-26324-1-git-send-email-m.szyprowski@samsung.com> <20140818233201.GL9809@8bytes.org> <53F2E9AD.9030308@samsung.com> <53F3375E.6030402@suse.de> <53F33C9C.1080601@samsung.com> In-Reply-To: <53F33C9C.1080601@samsung.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, Am 19.08.2014 14:01, schrieb Marek Szyprowski: > On 2014-08-19 13:39, Andreas Färber wrote: >> I'm working on 5250 based Spring Chromebook and noticed that v3.17-rc1 >> got some more iommu support. With the new CONFIG_DRM_EXYNOS_IOMMU=y my >> machine stops booting. So I'm wondering, is any of this a fix for 3.17, >> or is all of this "unrelated" -next material? > > This is probably a side effect of patch > 3170447c1f264d51b8d1f3898bf2588588a64fdc > ("iommu/exynos: Select ARM_DMA_USE_IOMMU"). It added selection of > ARM_DMA_USE_IOMMU > symbol, on which IOMMU support in Exynos DRM subsystem depends. However > selecting > this symbol is all that this patch does, without providing any code code > which > implements real support for ARM DMA IOMMU integration, which is needed > by Exynos > DRM driver. Please disable CONFIG_DRM_EXYNOS_IOMMU in kernel .config and > your > system should be bootable again. Yes, that's what my report implied. :) I'm bringing this up for -rc2 though: It sounds as if that option should remain unavailable until the required code is in? Thanks. >> Also, are you or someone >> working on the respective DT changes for Exynos5? > > I can prepare DT changes for Exynos5 as well, but first I wanted to > clarify if > everyone involved in generic IOMMU bindings and Exynos IOMMU driver > agrees on my > proposal. Sure. I'm updating my old spring-bridge.v6 branch [1] to 3.17-rc1 [2], which involves three drm bridge patches rebased onto the new drm panel prepare/unprepare infrastructure plus two LVDS DT patches in addition to the IOMMU patches. That old branch included DT changes for 5250 in "ARM: dts: add System MMU nodes of Exynos SoCs", but that'll probably need updating for the new bindings. Regards, Andreas [1] https://github.com/afaerber/linux/commits/spring-bridge.v6 [2] https://github.com/afaerber/linux/commits/spring-next -- SUSE LINUX Products GmbH, Maxfeldstr. 5, 90409 Nürnberg, Germany GF: Jeff Hawn, Jennifer Guild, Felix Imendörffer; HRB 16746 AG Nürnberg