@@ -121,20 +121,11 @@ static inline unsigned long dma_max_pfn(struct device *dev)
}
#define dma_max_pfn(dev) dma_max_pfn(dev)
-static inline void arch_setup_dma_ops(struct device *dev, u64 mask,
- u64 dma_base, u64 size,
- unsigned long offset,
- struct iommu_dma_mapping *iommu,
- bool coherent)
-{
- dev->coherent_dma_mask = mask;
- dev->dma_mask = &dev->coherent_dma_mask;
- dev->dma_pfn_offset = offset;
-
- if (coherent)
- set_dma_ops(dev, &arm_coherent_dma_ops);
-}
#define arch_setup_dma_ops arch_setup_dma_ops
+extern void arch_setup_dma_ops(struct device *dev, u64 mask, u64 dma_base,
+ u64 size, unsigned long offset,
+ struct iommu_dma_mapping *iommu,
+ bool coherent);
static inline dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)
{
@@ -2041,10 +2041,9 @@ EXPORT_SYMBOL_GPL(arm_iommu_release_mapping);
* @mapping: io address space mapping structure (returned from
* arm_iommu_create_mapping)
*
- * Attaches specified io address space mapping to the provided device,
- * this replaces the dma operations (dma_map_ops pointer) with the
- * IOMMU aware version. More than one client might be attached to
- * the same io address space mapping.
+ * Attaches specified io address space mapping to the provided device.
+ * More than one client might be attached to the same io address space
+ * mapping.
*/
int arm_iommu_attach_device(struct device *dev,
struct dma_iommu_mapping *mapping)
@@ -2057,7 +2056,6 @@ int arm_iommu_attach_device(struct device *dev,
kref_get(&mapping->kref);
dev->archdata.mapping = mapping;
- set_dma_ops(dev, &iommu_ops);
pr_debug("Attached IOMMU controller to %s device.\n", dev_name(dev));
return 0;
@@ -2069,7 +2067,6 @@ EXPORT_SYMBOL_GPL(arm_iommu_attach_device);
* @dev: valid struct device pointer
*
* Detaches the provided device from a previously attached map.
- * This voids the dma operations (dma_map_ops pointer)
*/
void arm_iommu_detach_device(struct device *dev)
{
@@ -2084,10 +2081,69 @@ void arm_iommu_detach_device(struct device *dev)
iommu_detach_device(mapping->domain, dev);
kref_put(&mapping->kref, release_iommu_mapping);
dev->archdata.mapping = NULL;
- set_dma_ops(dev, NULL);
pr_debug("Detached IOMMU controller from %s device.\n", dev_name(dev));
}
EXPORT_SYMBOL_GPL(arm_iommu_detach_device);
-#endif
+static bool arm_setup_iommu_dma_ops(struct device *dev, u64 dma_base, u64 size)
+{
+ struct dma_iommu_mapping *mapping;
+
+ mapping = arm_iommu_create_mapping(dev->bus, dma_base, size);
+ if (IS_ERR(mapping)) {
+ pr_warn("Failed to create %llu-byte IOMMU mapping for device %s\n",
+ size, dev_name(dev));
+ return false;
+ }
+
+ if (arm_iommu_attach_device(dev, mapping)) {
+ pr_warn("Failed to attach device %s to IOMMU mapping\n",
+ dev_name(dev));
+ arm_iommu_release_mapping(mapping);
+ return false;
+ }
+
+ return true;
+}
+
+static struct dma_map_ops *arm_get_iommu_dma_map_ops(bool coherent)
+{
+ return coherent ? &iommu_coherent_ops : &iommu_ops;
+}
+
+#else
+
+static bool arm_setup_iommu_dma_ops(struct device *dev, u64 dma_base, u64 size)
+{
+ return false;
+}
+
+#define arm_get_iommu_dma_map_ops arm_get_dma_map_ops
+
+#endif /* CONFIG_ARM_DMA_USE_IOMMU */
+
+static struct dma_map_ops *arm_get_dma_map_ops(bool coherent)
+{
+ return coherent ? &arm_coherent_dma_ops : &arm_dma_ops;
+}
+
+void arch_setup_dma_ops(struct device *dev, u64 mask, u64 dma_base, u64 size,
+ unsigned long offset, struct iommu_dma_mapping *iommu,
+ bool coherent)
+{
+ struct dma_map_ops *dma_ops;
+
+ dev->coherent_dma_mask = mask;
+ dev->dma_mask = &dev->coherent_dma_mask;
+
+ if (iommu && arm_setup_iommu_dma_ops(dev, dma_base, size)) {
+ dma_ops = arm_get_iommu_dma_map_ops(coherent);
+ } else {
+ dev->dma_pfn_offset = offset;
+ dma_ops = arm_get_dma_map_ops(coherent);
+ }
+
+ set_dma_ops(dev, dma_ops);
+}
+EXPORT_SYMBOL_GPL(arch_setup_dma_ops);
This patch plumbs the existing ARM IOMMU DMA infrastructure (which isn't actually called outside of a few drivers) into arch_setup_dma_ops, so that we can use IOMMUs for DMA transfers in a more generic fashion. Since this significantly complicates the arch_setup_dma_ops function, it is moved out of line into dma-mapping.c. If CONFIG_ARM_DMA_USE_IOMMU is not set, the iommu paramater is ignored and the normal ops are used instead. Signed-off-by: Will Deacon <will.deacon@arm.com> --- arch/arm/include/asm/dma-mapping.h | 17 +++------ arch/arm/mm/dma-mapping.c | 72 +++++++++++++++++++++++++++++++++----- 2 files changed, 68 insertions(+), 21 deletions(-)