From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thierry Reding Subject: [PATCH 2/4] iommu/omap: Play nice in multi-platform builds Date: Wed, 4 Feb 2015 08:58:08 +0100 Message-ID: <1423036690-3862-3-git-send-email-thierry.reding@gmail.com> References: <1423036690-3862-1-git-send-email-thierry.reding@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1423036690-3862-1-git-send-email-thierry.reding-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: Joerg Roedel Cc: Nicolas Chauvet , Tony Lindgren , iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, Laurent Pinchart List-Id: iommu@lists.linux-foundation.org From: Thierry Reding The OMAP IOMMU driver unconditionally executes code and registers a struct iommu_ops with the platform bus irrespective of whether it runs on an OMAP SoC or not. This causes problems in multi-platform kernels where drivers for other SoCs will no longer be able to register their own struct iommu_ops or even try to use a struct iommu_ops for an IOMMU that obviously isn't there. The smallest fix I could think of is to check for the existence of any OMAP IOMMU devices in the device tree and skip initialization otherwise. This fixes a problem on Tegra20 where the DRM driver will try to use the obviously non-existent OMAP IOMMU. Reported-by: Nicolas Chauvet Cc: Tony Lindgren Cc: Suman Anna Cc: Laurent Pinchart Signed-off-by: Thierry Reding --- drivers/iommu/omap-iommu.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/iommu/omap-iommu.c b/drivers/iommu/omap-iommu.c index bbb7dcef02d3..e4d4f133a3b3 100644 --- a/drivers/iommu/omap-iommu.c +++ b/drivers/iommu/omap-iommu.c @@ -1377,6 +1377,9 @@ static int __init omap_iommu_init(void) const unsigned long flags = SLAB_HWCACHE_ALIGN; size_t align = 1 << 10; /* L2 pagetable alignement */ + if (!of_find_matching_node(NULL, omap_iommu_of_match)) + return 0; + p = kmem_cache_create("iopte_cache", IOPTE_TABLE_SIZE, align, flags, iopte_cachep_ctor); if (!p) @@ -1394,6 +1397,9 @@ subsys_initcall(omap_iommu_init); static void __exit omap_iommu_exit(void) { + if (!of_find_matching_node(NULL, omap_iommu_of_match)) + return; + kmem_cache_destroy(iopte_cachep); platform_driver_unregister(&omap_iommu_driver); -- 2.1.3