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Diffstat (limited to 'arch/x86/kernel/pci-swiotlb.c')
-rw-r--r--arch/x86/kernel/pci-swiotlb.c84
1 files changed, 84 insertions, 0 deletions
diff --git a/arch/x86/kernel/pci-swiotlb.c b/arch/x86/kernel/pci-swiotlb.c
new file mode 100644
index 00000000000..34f12e9996e
--- /dev/null
+++ b/arch/x86/kernel/pci-swiotlb.c
@@ -0,0 +1,84 @@
+/* Glue code to lib/swiotlb.c */
+
+#include <linux/pci.h>
+#include <linux/cache.h>
+#include <linux/module.h>
+#include <linux/swiotlb.h>
+#include <linux/bootmem.h>
+#include <linux/dma-mapping.h>
+
+#include <asm/iommu.h>
+#include <asm/swiotlb.h>
+#include <asm/dma.h>
+
+int swiotlb __read_mostly;
+
+void * __init swiotlb_alloc_boot(size_t size, unsigned long nslabs)
+{
+ return alloc_bootmem_low_pages(size);
+}
+
+void *swiotlb_alloc(unsigned order, unsigned long nslabs)
+{
+ return (void *)__get_free_pages(GFP_DMA | __GFP_NOWARN, order);
+}
+
+dma_addr_t swiotlb_phys_to_bus(struct device *hwdev, phys_addr_t paddr)
+{
+ return paddr;
+}
+
+phys_addr_t swiotlb_bus_to_phys(dma_addr_t baddr)
+{
+ return baddr;
+}
+
+int __weak swiotlb_arch_range_needs_mapping(phys_addr_t paddr, size_t size)
+{
+ return 0;
+}
+
+static void *x86_swiotlb_alloc_coherent(struct device *hwdev, size_t size,
+ dma_addr_t *dma_handle, gfp_t flags)
+{
+ void *vaddr;
+
+ vaddr = dma_generic_alloc_coherent(hwdev, size, dma_handle, flags);
+ if (vaddr)
+ return vaddr;
+
+ return swiotlb_alloc_coherent(hwdev, size, dma_handle, flags);
+}
+
+struct dma_map_ops swiotlb_dma_ops = {
+ .mapping_error = swiotlb_dma_mapping_error,
+ .alloc_coherent = x86_swiotlb_alloc_coherent,
+ .free_coherent = swiotlb_free_coherent,
+ .sync_single_for_cpu = swiotlb_sync_single_for_cpu,
+ .sync_single_for_device = swiotlb_sync_single_for_device,
+ .sync_single_range_for_cpu = swiotlb_sync_single_range_for_cpu,
+ .sync_single_range_for_device = swiotlb_sync_single_range_for_device,
+ .sync_sg_for_cpu = swiotlb_sync_sg_for_cpu,
+ .sync_sg_for_device = swiotlb_sync_sg_for_device,
+ .map_sg = swiotlb_map_sg_attrs,
+ .unmap_sg = swiotlb_unmap_sg_attrs,
+ .map_page = swiotlb_map_page,
+ .unmap_page = swiotlb_unmap_page,
+ .dma_supported = NULL,
+};
+
+void __init pci_swiotlb_init(void)
+{
+ /* don't initialize swiotlb if iommu=off (no_iommu=1) */
+#ifdef CONFIG_X86_64
+ if (!iommu_detected && !no_iommu && max_pfn > MAX_DMA32_PFN)
+ swiotlb = 1;
+#endif
+ if (swiotlb_force)
+ swiotlb = 1;
+ if (swiotlb) {
+ printk(KERN_INFO "PCI-DMA: Using software bounce buffering for IO (SWIOTLB)\n");
+ swiotlb_init();
+ dma_ops = &swiotlb_dma_ops;
+ }
+}