diff options
| author | Will Deacon <will.deacon@arm.com> | 2014-08-27 16:20:32 +0100 |
|---|---|---|
| committer | Will Deacon <will.deacon@arm.com> | 2014-12-01 16:50:38 +0000 |
| commit | 7eba1d51485197fa77c43c42eae3ce04b4b1c1c0 (patch) | |
| tree | ace7a25c7d2aaf0e6250d60db0ee08faf55bf201 | |
| parent | d0f60a44f5120a8e1c48995285c7d8d1e4915b35 (diff) | |
iommu: provide helper function to configure an IOMMU for an of master
The generic IOMMU device-tree bindings can be used to add arbitrary OF
masters to an IOMMU with a compliant binding.
This patch introduces of_iommu_configure, which does exactly that.
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Joerg Roedel <jroedel@suse.de>
Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
| -rw-r--r-- | drivers/iommu/Kconfig | 2 | ||||
| -rw-r--r-- | drivers/iommu/of_iommu.c | 33 | ||||
| -rw-r--r-- | include/linux/of_iommu.h | 6 |
3 files changed, 40 insertions, 1 deletions
diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig index dd5112265cc9..6d13f962f156 100644 --- a/drivers/iommu/Kconfig +++ b/drivers/iommu/Kconfig @@ -15,7 +15,7 @@ if IOMMU_SUPPORT config OF_IOMMU def_bool y - depends on OF + depends on OF && IOMMU_API config FSL_PAMU bool "Freescale IOMMU support" diff --git a/drivers/iommu/of_iommu.c b/drivers/iommu/of_iommu.c index 89b903406968..73236d3cc955 100644 --- a/drivers/iommu/of_iommu.c +++ b/drivers/iommu/of_iommu.c @@ -18,6 +18,7 @@ */ #include <linux/export.h> +#include <linux/iommu.h> #include <linux/limits.h> #include <linux/of.h> #include <linux/of_iommu.h> @@ -93,6 +94,38 @@ int of_get_dma_window(struct device_node *dn, const char *prefix, int index, } EXPORT_SYMBOL_GPL(of_get_dma_window); +struct iommu_ops *of_iommu_configure(struct device *dev) +{ + struct of_phandle_args iommu_spec; + struct device_node *np; + struct iommu_ops *ops = NULL; + int idx = 0; + + /* + * We don't currently walk up the tree looking for a parent IOMMU. + * See the `Notes:' section of + * Documentation/devicetree/bindings/iommu/iommu.txt + */ + while (!of_parse_phandle_with_args(dev->of_node, "iommus", + "#iommu-cells", idx, + &iommu_spec)) { + np = iommu_spec.np; + ops = of_iommu_get_ops(np); + + if (!ops || !ops->of_xlate || ops->of_xlate(dev, &iommu_spec)) + goto err_put_node; + + of_node_put(np); + idx++; + } + + return ops; + +err_put_node: + of_node_put(np); + return NULL; +} + void __init of_iommu_init(void) { struct device_node *np; diff --git a/include/linux/of_iommu.h b/include/linux/of_iommu.h index 5762cdc8effe..d03abbb11c34 100644 --- a/include/linux/of_iommu.h +++ b/include/linux/of_iommu.h @@ -1,6 +1,7 @@ #ifndef __OF_IOMMU_H #define __OF_IOMMU_H +#include <linux/device.h> #include <linux/iommu.h> #include <linux/of.h> @@ -11,6 +12,7 @@ extern int of_get_dma_window(struct device_node *dn, const char *prefix, size_t *size); extern void of_iommu_init(void); +extern struct iommu_ops *of_iommu_configure(struct device *dev); #else @@ -22,6 +24,10 @@ static inline int of_get_dma_window(struct device_node *dn, const char *prefix, } static inline void of_iommu_init(void) { } +static inline struct iommu_ops *of_iommu_configure(struct device *dev) +{ + return NULL; +} #endif /* CONFIG_OF_IOMMU */ |