From mboxrd@z Thu Jan 1 00:00:00 1970 From: Will Deacon Subject: Re: [PATCH v2 4/7] iommu/of: Handle iommu-map property for PCI Date: Tue, 14 Jun 2016 15:45:59 +0100 Message-ID: <20160614144559.GK19407@arm.com> References: <69952eda726c370ed6e5739bdd2e32cdc4466bfb.1464966939.git.robin.murphy@arm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <69952eda726c370ed6e5739bdd2e32cdc4466bfb.1464966939.git.robin.murphy-5wv7dgnIgG8@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: Robin Murphy Cc: devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, robh+dt-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, frowand.list-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org List-Id: iommu@lists.linux-foundation.org On Fri, Jun 03, 2016 at 06:15:39PM +0100, Robin Murphy wrote: > Now that we have a way to pick up the RID translation and target IOMMU, > hook up of_iommu_configure() to bring PCI devices into the of_xlate > mechanism and allow them IOMMU-backed DMA ops without the need for > driver-specific handling. > > CC: Rob Herring > CC: Frank Rowand > Signed-off-by: Robin Murphy > --- > > v2: Skip disabled IOMMUs. > > drivers/iommu/of_iommu.c | 44 +++++++++++++++++++++++++++++++++++++------- > 1 file changed, 37 insertions(+), 7 deletions(-) > > diff --git a/drivers/iommu/of_iommu.c b/drivers/iommu/of_iommu.c > index 662f9a600f4f..5716131199b3 100644 > --- a/drivers/iommu/of_iommu.c > +++ b/drivers/iommu/of_iommu.c > @@ -22,6 +22,7 @@ > #include > #include > #include > +#include > #include > > static const struct of_device_id __iommu_of_table_sentinel > @@ -134,20 +135,49 @@ const struct iommu_ops *of_iommu_get_ops(struct device_node *np) > return ops; > } > > +static int __get_pci_rid(struct pci_dev *pdev, u16 alias, void *data) > +{ > + struct of_phandle_args *iommu_spec = data; > + > + iommu_spec->args[0] = alias; > + return iommu_spec->np == pdev->bus->dev.of_node; > +} > + > const struct iommu_ops *of_iommu_configure(struct device *dev, > struct device_node *master_np) > { > struct of_phandle_args iommu_spec; > - struct device_node *np; > + struct device_node *np = NULL; > const struct iommu_ops *ops = NULL; > int idx; > > - /* > - * We can't do much for PCI devices without knowing how > - * device IDs are wired up from the PCI bus to the IOMMU. > - */ > - if (dev_is_pci(dev)) > - return NULL; > + if (dev_is_pci(dev)) { > + /* > + * Start by tracing the RID alias down the PCI topology as > + * far as the host bridge whose OF node we have... > + */ > + iommu_spec.np = master_np; > + pci_for_each_dma_alias(to_pci_dev(dev), __get_pci_rid, > + &iommu_spec); > + /* > + * ...then find out what that becomes once it escapes the PCI > + * bus into the system beyond, and which IOMMU it ends up at. > + */ > + if (of_pci_map_rid(master_np, "iommu-map", iommu_spec.args[0], > + &np, iommu_spec.args) || > + !of_device_is_available(np)) > + return NULL; Hmm, do we need to of_node_put(np) in the case that it's not available? Will From mboxrd@z Thu Jan 1 00:00:00 1970 From: will.deacon@arm.com (Will Deacon) Date: Tue, 14 Jun 2016 15:45:59 +0100 Subject: [PATCH v2 4/7] iommu/of: Handle iommu-map property for PCI In-Reply-To: <69952eda726c370ed6e5739bdd2e32cdc4466bfb.1464966939.git.robin.murphy@arm.com> References: <69952eda726c370ed6e5739bdd2e32cdc4466bfb.1464966939.git.robin.murphy@arm.com> Message-ID: <20160614144559.GK19407@arm.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Fri, Jun 03, 2016 at 06:15:39PM +0100, Robin Murphy wrote: > Now that we have a way to pick up the RID translation and target IOMMU, > hook up of_iommu_configure() to bring PCI devices into the of_xlate > mechanism and allow them IOMMU-backed DMA ops without the need for > driver-specific handling. > > CC: Rob Herring > CC: Frank Rowand > Signed-off-by: Robin Murphy > --- > > v2: Skip disabled IOMMUs. > > drivers/iommu/of_iommu.c | 44 +++++++++++++++++++++++++++++++++++++------- > 1 file changed, 37 insertions(+), 7 deletions(-) > > diff --git a/drivers/iommu/of_iommu.c b/drivers/iommu/of_iommu.c > index 662f9a600f4f..5716131199b3 100644 > --- a/drivers/iommu/of_iommu.c > +++ b/drivers/iommu/of_iommu.c > @@ -22,6 +22,7 @@ > #include > #include > #include > +#include > #include > > static const struct of_device_id __iommu_of_table_sentinel > @@ -134,20 +135,49 @@ const struct iommu_ops *of_iommu_get_ops(struct device_node *np) > return ops; > } > > +static int __get_pci_rid(struct pci_dev *pdev, u16 alias, void *data) > +{ > + struct of_phandle_args *iommu_spec = data; > + > + iommu_spec->args[0] = alias; > + return iommu_spec->np == pdev->bus->dev.of_node; > +} > + > const struct iommu_ops *of_iommu_configure(struct device *dev, > struct device_node *master_np) > { > struct of_phandle_args iommu_spec; > - struct device_node *np; > + struct device_node *np = NULL; > const struct iommu_ops *ops = NULL; > int idx; > > - /* > - * We can't do much for PCI devices without knowing how > - * device IDs are wired up from the PCI bus to the IOMMU. > - */ > - if (dev_is_pci(dev)) > - return NULL; > + if (dev_is_pci(dev)) { > + /* > + * Start by tracing the RID alias down the PCI topology as > + * far as the host bridge whose OF node we have... > + */ > + iommu_spec.np = master_np; > + pci_for_each_dma_alias(to_pci_dev(dev), __get_pci_rid, > + &iommu_spec); > + /* > + * ...then find out what that becomes once it escapes the PCI > + * bus into the system beyond, and which IOMMU it ends up at. > + */ > + if (of_pci_map_rid(master_np, "iommu-map", iommu_spec.args[0], > + &np, iommu_spec.args) || > + !of_device_is_available(np)) > + return NULL; Hmm, do we need to of_node_put(np) in the case that it's not available? Will