From: robin.murphy@arm•com (Robin Murphy)
To: linux-arm-kernel@lists•infradead.org
Subject: [PATCH v2 4/7] iommu/of: Handle iommu-map property for PCI
Date: Wed, 15 Jun 2016 12:21:27 +0100 [thread overview]
Message-ID: <57613A37.6080600@arm.com> (raw)
In-Reply-To: <20160614144559.GK19407@arm.com>
On 14/06/16 15:45, Will Deacon wrote:
> 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 <robh+dt@kernel•org>
>> CC: Frank Rowand <frowand.list@gmail•com>
>> Signed-off-by: Robin Murphy <robin.murphy@arm•com>
>> ---
>>
>> 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 <linux/limits.h>
>> #include <linux/of.h>
>> #include <linux/of_iommu.h>
>> +#include <linux/of_pci.h>
>> #include <linux/slab.h>
>>
>> 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?
Ah yes, now I see; I moved the put into the loop iteration for the
non-PCI case so that a "continue" does the job, but I've not handled the
equivalent here.
Robin.
>
> Will
>
next prev parent reply other threads:[~2016-06-15 11:21 UTC|newest]
Thread overview: 29+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-06-03 17:15 [PATCH v2 0/7] Generic DT bindings for PCI IOMMUs and ARM SMMUv3 Robin Murphy
2016-06-03 17:15 ` [PATCH v2 1/7] iommu/of: Respect disabled IOMMUs Robin Murphy
2016-06-14 14:11 ` Will Deacon
2016-06-14 15:04 ` Robin Murphy
2016-06-03 17:15 ` [PATCH v2 2/7] Docs: dt: add PCI IOMMU map bindings Robin Murphy
2016-06-14 14:16 ` Will Deacon
2016-06-03 17:15 ` [PATCH v2 3/7] of/irq: Break out msi-map lookup (again) Robin Murphy
2016-06-04 8:10 ` Marc Zyngier
2016-06-14 14:37 ` Will Deacon
2016-06-14 18:12 ` Robin Murphy
2016-06-14 18:20 ` Will Deacon
2016-06-14 17:01 ` Rob Herring
2016-06-15 10:16 ` Robin Murphy
2016-06-03 17:15 ` [PATCH v2 4/7] iommu/of: Handle iommu-map property for PCI Robin Murphy
2016-06-14 14:45 ` Will Deacon
2016-06-15 11:21 ` Robin Murphy [this message]
2016-06-03 17:15 ` [PATCH v2 5/7] iommu/arm-smmu: Implement of_xlate() for SMMUv3 Robin Murphy
2016-06-14 15:07 ` Will Deacon
2016-06-14 16:11 ` Robin Murphy
2016-06-03 17:15 ` [PATCH v2 6/7] iommu/arm-smmu: Finish off SMMUv3 default domain support Robin Murphy
2016-06-06 15:47 ` Jean-Philippe Brucker
2016-06-06 17:22 ` Robin Murphy
2016-06-14 15:59 ` Will Deacon
2016-06-03 17:15 ` [PATCH v2 7/7] iommu/arm-smmu: Support non-PCI devices with SMMUv3 Robin Murphy
2016-06-14 15:16 ` Will Deacon
2016-06-15 1:22 ` Leizhen (ThunderTown)
2016-06-17 1:54 ` Leizhen (ThunderTown)
2016-06-17 9:14 ` Robin Murphy
2016-06-21 8:36 ` Leizhen (ThunderTown)
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