From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marek Szyprowski Subject: Re: [PATCH 1/1] ARM: exynos_defconfig: Disable IOMMU support Date: Wed, 04 Mar 2015 09:50:14 +0100 Message-ID: <54F6C746.606@samsung.com> References: <1424173109-30347-1-git-send-email-javier.martinez@collabora.co.uk> <7hioehu8cn.fsf@linaro.org> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-reply-to: <7hioehu8cn.fsf@linaro.org> Sender: linux-kernel-owner@vger.kernel.org To: Kevin Hilman , Javier Martinez Canillas Cc: Kukjin Kim , Olof Johansson , Krzysztof Kozlowski , Andreas Faerber , linux-samsung-soc@vger.kernel.org, linux-kernel@vger.kernel.org, tyler.baker@linaro.org, Andrzej Hajda , Inki Dae List-Id: linux-samsung-soc@vger.kernel.org Hello, On 2015-03-03 21:36, Kevin Hilman wrote: > Javier Martinez Canillas writes: > >> Enabling Exynos DRM IOMMU support for Exynos is currently broken and >> causes a BUG on exynos-iommu driver. This was not an issue since the >> options was disabled in exynos_defconfig but after commit 8dcc14f82f06 >> ("drm/exynos: IOMMU support should not be selectable by user"), it is >> selected if EXYNOS_IOMMU is enabled which is in exynos_defconfig. >> >> So a kernel built using exynos_defconfig after the mentioned commit >> fails to boot [0]. Disable IOMMU support in Exynos defconfig until >> things get sorted out. > So some other exynos boards started failing in next-20150303[1], and > appear are DRM failures. > > Interestingly, (re)enabling CONFIG_EXYNOS_IOMMU for these cause things to > work again. Even more intersting, with IOMMU enabled, peach-pi is > > I'm starting to think it's the DRM driver that needs to be disabled > until it actually gets some testing, rathre than disabling IOMMU. Well, this only shows that broken patch has been merged to exynos-drm-next kernel tree. I think that we should keep Exynos DRM enabled and give Exynos DRM developers a chance to fix their stuff and then test their stuff. Best regards -- Marek Szyprowski, PhD Samsung R&D Institute Poland