Define the map_resource/unmap_resource callbacks for the dma_iommu_ops
used by several powerpc platforms. The map_resource callback is called
when trying to map a mmio resource through the dma_map_resource()
driver API.
For now, the callback returns an invalid address for devices using
translations, but will "direct" map the resource when in bypass
mode. Previous behavior for dma_map_resource() was to always return an
invalid address.
We also call an optional platform-specific controller op in
case some setup is needed for the platform.
Signed-off-by: Frederic Barrat <fbar...@linux.ibm.com>
Signed-off-by: Max Gurtovoy <m...@mellanox.com>
---
changes from v1:
- rename pci_controller_ops callback to
dma_direct_map_resource/dma_direct_unmap_resource
- cosmetic changes to make the code more readable
---
arch/powerpc/include/asm/pci-bridge.h | 7 +++++++
arch/powerpc/kernel/dma-iommu.c | 31 +++++++++++++++++++++++++++++++
2 files changed, 38 insertions(+)
diff --git a/arch/powerpc/include/asm/pci-bridge.h
b/arch/powerpc/include/asm/pci-bridge.h
index 69f4cb3..aca3724 100644
--- a/arch/powerpc/include/asm/pci-bridge.h
+++ b/arch/powerpc/include/asm/pci-bridge.h
@@ -44,6 +44,13 @@ struct pci_controller_ops {
#endif
void (*shutdown)(struct pci_controller *hose);
+ int (*dma_direct_map_resource)(struct pci_dev *pdev,
+ phys_addr_t phys_addr,
+ size_t size,
+ enum dma_data_direction dir);
+ void (*dma_direct_unmap_resource)(struct pci_dev *pdev,
+ dma_addr_t addr, size_t size,
+ enum dma_data_direction dir);
};
/*
diff --git a/arch/powerpc/kernel/dma-iommu.c b/arch/powerpc/kernel/dma-iommu.c
index e486d1d..049d000 100644
--- a/arch/powerpc/kernel/dma-iommu.c
+++ b/arch/powerpc/kernel/dma-iommu.c
@@ -108,6 +108,35 @@ static void dma_iommu_unmap_sg(struct device *dev, struct
scatterlist *sglist,
dma_direct_unmap_sg(dev, sglist, nelems, direction, attrs);
}
+static dma_addr_t dma_iommu_map_resource(struct device *dev,
+ phys_addr_t phys_addr, size_t size,
+ enum dma_data_direction dir,
+ unsigned long attrs)
+{
+ struct pci_dev *pdev = to_pci_dev(dev);
+ struct pci_controller *phb = pci_bus_to_host(pdev->bus);
+ struct pci_controller_ops *ops = &phb->controller_ops;
+
+ if (!dma_iommu_map_bypass(dev, attrs) ||
+ !ops->dma_direct_map_resource ||
+ ops->dma_direct_map_resource(pdev, phys_addr, size, dir))
+ return DMA_MAPPING_ERROR;
+
+ return dma_direct_map_resource(dev, phys_addr, size, dir, attrs);
+}
+
+static void dma_iommu_unmap_resource(struct device *dev, dma_addr_t dma_handle,
+ size_t size, enum dma_data_direction dir,
+ unsigned long attrs)
+{
+ struct pci_dev *pdev = to_pci_dev(dev);
+ struct pci_controller *phb = pci_bus_to_host(pdev->bus);
+ struct pci_controller_ops *ops = &phb->controller_ops;
+
+ if (dma_iommu_map_bypass(dev, attrs) && ops->dma_direct_unmap_resource)
+ ops->dma_direct_unmap_resource(pdev, dma_handle, size, dir);
+}
+
static bool dma_iommu_bypass_supported(struct device *dev, u64 mask)
{
struct pci_dev *pdev = to_pci_dev(dev);
@@ -199,6 +228,8 @@ extern void dma_iommu_sync_sg_for_device(struct device *dev,
.free = dma_iommu_free_coherent,
.map_sg = dma_iommu_map_sg,
.unmap_sg = dma_iommu_unmap_sg,
+ .map_resource = dma_iommu_map_resource,
+ .unmap_resource = dma_iommu_unmap_resource,
.dma_supported = dma_iommu_dma_supported,
.map_page = dma_iommu_map_page,
.unmap_page = dma_iommu_unmap_page,
--
1.8.3.1
