sparc64: Enable 64-bit DMA

ATU 64bit addressing allows PCIe devices with 64bit DMA capabilities to use ATU for 64bit DMA. Signed-off-by: Tushar Dave <[email protected]> Reviewed-by: chris hyser <[email protected]> Acked-by: Sowmini Varadhan <[email protected]> Signed-off-by: David S. Miller <[email protected]>
libos-nuse · Nov 18, 2016 · d30a6b8 · d30a6b8
1 parent f08978b
commit d30a6b8
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Showing 2 changed files with 10 additions and 2 deletions.
diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig
@@ -93,6 +93,10 @@ config ARCH_ATU
 	bool
 	default y if SPARC64
 
+config ARCH_DMA_ADDR_T_64BIT
+	bool
+	default y if ARCH_ATU
+
 config IOMMU_HELPER
 	bool
 	default y if SPARC64

diff --git a/arch/sparc/kernel/iommu.c b/arch/sparc/kernel/iommu.c
@@ -760,8 +760,12 @@ int dma_supported(struct device *dev, u64 device_mask)
 	struct iommu *iommu = dev->archdata.iommu;
 	u64 dma_addr_mask = iommu->dma_addr_mask;
 
-	if (device_mask >= (1UL << 32UL))
-		return 0;
+	if (device_mask > DMA_BIT_MASK(32)) {
+		if (iommu->atu)
+			dma_addr_mask = iommu->atu->dma_addr_mask;
+		else
+			return 0;
+	}
 
 	if ((device_mask & dma_addr_mask) == dma_addr_mask)
 		return 1;