[PATCH 14/33] powerpc/dart: use the generic iommu bypass code

Christoph Hellwig
2018-10-09T13:26:16Z

Use the generic iommu bypass code instead of overriding set_dma_mask.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
arch/powerpc/sysdev/dart_iommu.c | 45 +++++++++++---------------------
1 file changed, 15 insertions(+), 30 deletions(-)

diff --git a/arch/powerpc/sysdev/dart_iommu.c b/arch/powerpc/sysdev/dart_iommu.c
index ce5dd2048f57..e7d1645a2d2e 100644
--- a/arch/powerpc/sysdev/dart_iommu.c
+++ b/arch/powerpc/sysdev/dart_iommu.c
@@ -360,13 +360,6 @@ static void iommu_table_dart_setup(void)
set_bit(iommu_table_dart.it_size - 1, iommu_table_dart.it_map);
}

-static void pci_dma_dev_setup_dart(struct pci_dev *dev)
-{
- if (dart_is_u4)
- set_dma_offset(&dev->dev, DART_U4_BYPASS_BASE);
- set_iommu_table_base(&dev->dev, &iommu_table_dart);
-}
-
static void pci_dma_bus_setup_dart(struct pci_bus *bus)
{
if (!iommu_table_dart_inited) {
@@ -390,27 +383,16 @@ static bool dart_device_on_pcie(struct device *dev)
return false;
}

-static int dart_dma_set_mask(struct device *dev, u64 dma_mask)
+static void pci_dma_dev_setup_dart(struct pci_dev *dev)
{
- if (!dev->dma_mask || !dma_supported(dev, dma_mask))
- return -EIO;
-
- /* U4 supports a DART bypass, we use it for 64-bit capable
- * devices to improve performances. However, that only works
- * for devices connected to U4 own PCIe interface, not bridged
- * through hypertransport. We need the device to support at
- * least 40 bits of addresses.
- */
- if (dart_device_on_pcie(dev) && dma_mask >= DMA_BIT_MASK(40)) {
- dev_info(dev, "Using 64-bit DMA iommu bypass\n");
- set_dma_ops(dev, &dma_nommu_ops);
- } else {
- dev_info(dev, "Using 32-bit DMA via iommu\n");
- set_dma_ops(dev, &dma_iommu_ops);
- }
+ if (dart_is_u4 && dart_device_on_pcie(&dev->dev))
+ set_dma_offset(&dev->dev, DART_U4_BYPASS_BASE);
+ set_iommu_table_base(&dev->dev, &iommu_table_dart);
+}

- *dev->dma_mask = dma_mask;
- return 0;
+static bool iommu_bypass_supported_dart(struct pci_dev *dev, u64 mask)
+{
+ return dart_is_u4 && dart_device_on_pcie(&dev->dev);
}

void __init iommu_init_early_dart(struct pci_controller_ops *controller_ops)
@@ -430,12 +412,15 @@ void __init iommu_init_early_dart(struct pci_controller_ops *controller_ops)
if (dart_init(dn) != 0)
return;

- /* Setup bypass if supported */
- if (dart_is_u4)
- ppc_md.dma_set_mask = dart_dma_set_mask;
-
+ /*
+ * U4 supports a DART bypass, we use it for 64-bit capable devices to
+ * improve performance. However, that only works for devices connected
+ * to the U4 own PCIe interface, not bridged through hypertransport.
+ * We need the device to support at least 40 bits of addresses.
+ */
controller_ops->dma_dev_setup = pci_dma_dev_setup_dart;
controller_ops->dma_bus_setup = pci_dma_bus_setup_dart;
+ controller_ops->iommu_bypass_supported = iommu_bypass_supported_dart;

/* Setup pci_dma ops */
set_pci_dma_ops(&dma_iommu_ops);
--
2.19.0