From mboxrd@z Thu Jan 1 00:00:00 1970 From: Laurent Pinchart Subject: Re: [PATCH 2/2] iommu/omap: Fix iommu archdata name for DT-based devices Date: Fri, 05 Sep 2014 14:11:59 +0300 Message-ID: <2047677.moNByOyTBi@avalon> References: <1409788712-10741-1-git-send-email-s-anna@ti.com> <2755871.jyTSgisx8z@avalon> <5408D701.7070609@ti.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7Bit Return-path: Received: from galahad.ideasonboard.com ([185.26.127.97]:58301 "EHLO galahad.ideasonboard.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756675AbaIELMB (ORCPT ); Fri, 5 Sep 2014 07:12:01 -0400 In-Reply-To: <5408D701.7070609@ti.com> Sender: linux-omap-owner@vger.kernel.org List-Id: linux-omap@vger.kernel.org To: Suman Anna Cc: Joerg Roedel , Florian Vaussard , iommu@lists.linux-foundation.org, linux-omap@vger.kernel.org Hi Suman, On Thursday 04 September 2014 16:17:53 Suman Anna wrote: > Hi Laurent, > > > On Wednesday 03 September 2014 18:58:32 Suman Anna wrote: > >> A device is tied to an iommu through its archdata field. The archdata > >> is allocated on the fly for DT-based devices automatically through the > >> .add_device iommu ops. The current logic incorrectly assigned the name > >> of the IOMMU user device, instead of the name of the IOMMU device as > >> required by the attach logic. Fix this issue so that DT-based devices > >> can attach successfully to an IOMMU domain. > >> > >> Signed-off-by: Suman Anna > >> --- > >> > >> drivers/iommu/omap-iommu.c | 10 +++++++++- > >> 1 file changed, 9 insertions(+), 1 deletion(-) > >> > >> diff --git a/drivers/iommu/omap-iommu.c b/drivers/iommu/omap-iommu.c > >> index f245d51..f47ac03 100644 > >> --- a/drivers/iommu/omap-iommu.c > >> +++ b/drivers/iommu/omap-iommu.c > >> @@ -26,6 +26,7 @@ > >> #include > >> #include > >> #include > >> +#include > >> > >> #include > >> > >> @@ -1244,6 +1245,7 @@ static int omap_iommu_add_device(struct device > >> *dev) > >> { > >> struct omap_iommu_arch_data *arch_data; > >> struct device_node *np; > >> + struct platform_device *pdev; > >> > >> /* > >> * Allocate the archdata iommu structure for DT-based devices. > >> @@ -1258,13 +1260,19 @@ static int omap_iommu_add_device(struct device > >> *dev) > >> if (!np) > >> return 0; > >> > >> + pdev = of_find_device_by_node(np); > >> + if (WARN_ON(!pdev)) { > >> + of_node_put(np); > >> + return -EINVAL; > >> + } > > > > I might be wrong, but I don't think there's a guarantee at this point that > > the IOMMU device is already instantiated :-/ > > The omap_iommu_init which registers the iommu_ops is a subsys_initcall, > so the platform devices are guaranteed to be created by this point. OK, no worries then. > My test on OMAP4 in fact has the dsp node created before the IOMMU node, > and this is not an issue. I have added the WARN_ON in case some one has > the IOMMU node disabled, but try to use it. > > > Will Deacon has posted patches that rework the IOMMU core for better DT > > integration, have you seen them ? > > Can you point out the thread? Are you talking about > http://marc.info/?l=linux-arm-kernel&m=140968072117851&w=2? Yes that's the one. -- Regards, Laurent Pinchart