IOMMU devices on the bus need to be poplulated first, then iommu master devices are done later. With CONFIG_OF_IOMMU, "iommus=" DT binding would be used to identify whether a device can be an iommu msater or not. If a device can, we'll defer to populate that device till an depending iommu device is populated. Signed-off-by: Hiroshi Doyu <hdoyu@xxxxxxxxxx> --- v6: Spinned off only of_iommu part from: [PATCHv5 2/9] driver/core: populate devices in order for IOMMUs v5: Use "iommus=" binding instread of arm,smmu's "#stream-id-cells". v4: This is newly added, and the successor of the following RFC: [RFC][PATCHv3+ 1/2] driver/core: Add of_iommu_attach() http://lists.linuxfoundation.org/pipermail/iommu/2013-November/006914.html Signed-off-by: Hiroshi Doyu <hdoyu@xxxxxxxxxx> --- drivers/iommu/of_iommu.c | 14 ++++++++++++++ include/linux/of_iommu.h | 6 ++++++ 2 files changed, 20 insertions(+) diff --git a/drivers/iommu/of_iommu.c b/drivers/iommu/of_iommu.c index 5d1aeb9..557c0c8 100644 --- a/drivers/iommu/of_iommu.c +++ b/drivers/iommu/of_iommu.c @@ -125,3 +125,17 @@ int of_get_dma_window(struct device_node *dn, const char *prefix, int index, return 0; } EXPORT_SYMBOL_GPL(of_get_dma_window); + +int of_iommu_attach(struct device *dev) +{ + const __be32 *cur, *end; + struct of_phandle_args args; + + of_property_for_each_phandle_with_args(dev->of_node, "iommus", + "#iommu-cells", 0, args, cur, end) { + if (!of_find_iommu_by_node(args.np)) + return -EPROBE_DEFER; + } + + return 0; +} diff --git a/include/linux/of_iommu.h b/include/linux/of_iommu.h index a0aa9d4..14c9a5c 100644 --- a/include/linux/of_iommu.h +++ b/include/linux/of_iommu.h @@ -14,6 +14,7 @@ extern int of_get_dma_window(struct device_node *dn, const char *prefix, extern void iommu_add(struct iommu *iommu); extern void iommu_del(struct iommu *iommu); +extern int of_iommu_attach(struct device *dev); #else @@ -32,6 +33,11 @@ static inline void iommu_del(struct iommu *iommu) { } +static inline int of_iommu_attach(struct device *dev) +{ + return 0; +} + #endif /* CONFIG_OF_IOMMU */ #endif /* __OF_IOMMU_H */ -- 1.8.1.5 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
