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Diffstat (limited to 'arch/x86/kernel/pci-swiotlb.c')
-rw-r--r--arch/x86/kernel/pci-swiotlb.c44
1 files changed, 37 insertions, 7 deletions
diff --git a/arch/x86/kernel/pci-swiotlb.c b/arch/x86/kernel/pci-swiotlb.c
index a5bc528d4328..8f972cbddef0 100644
--- a/arch/x86/kernel/pci-swiotlb.c
+++ b/arch/x86/kernel/pci-swiotlb.c
@@ -10,7 +10,8 @@
#include <asm/iommu.h>
#include <asm/swiotlb.h>
#include <asm/dma.h>
-
+#include <asm/xen/swiotlb-xen.h>
+#include <asm/iommu_table.h>
int swiotlb __read_mostly;
static void *x86_swiotlb_alloc_coherent(struct device *hwdev, size_t size,
@@ -41,25 +42,42 @@ static struct dma_map_ops swiotlb_dma_ops = {
};
/*
- * pci_swiotlb_detect - set swiotlb to 1 if necessary
+ * pci_swiotlb_detect_override - set swiotlb to 1 if necessary
*
* This returns non-zero if we are forced to use swiotlb (by the boot
* option).
*/
-int __init pci_swiotlb_detect(void)
+int __init pci_swiotlb_detect_override(void)
{
int use_swiotlb = swiotlb | swiotlb_force;
+ if (swiotlb_force)
+ swiotlb = 1;
+
+ return use_swiotlb;
+}
+IOMMU_INIT_FINISH(pci_swiotlb_detect_override,
+ pci_xen_swiotlb_detect,
+ pci_swiotlb_init,
+ pci_swiotlb_late_init);
+
+/*
+ * if 4GB or more detected (and iommu=off not set) return 1
+ * and set swiotlb to 1.
+ */
+int __init pci_swiotlb_detect_4gb(void)
+{
/* don't initialize swiotlb if iommu=off (no_iommu=1) */
#ifdef CONFIG_X86_64
if (!no_iommu && max_pfn > MAX_DMA32_PFN)
swiotlb = 1;
#endif
- if (swiotlb_force)
- swiotlb = 1;
-
- return use_swiotlb;
+ return swiotlb;
}
+IOMMU_INIT(pci_swiotlb_detect_4gb,
+ pci_swiotlb_detect_override,
+ pci_swiotlb_init,
+ pci_swiotlb_late_init);
void __init pci_swiotlb_init(void)
{
@@ -68,3 +86,15 @@ void __init pci_swiotlb_init(void)
dma_ops = &swiotlb_dma_ops;
}
}
+
+void __init pci_swiotlb_late_init(void)
+{
+ /* An IOMMU turned us off. */
+ if (!swiotlb)
+ swiotlb_free();
+ else {
+ printk(KERN_INFO "PCI-DMA: "
+ "Using software bounce buffering for IO (SWIOTLB)\n");
+ swiotlb_print_info();
+ }
+}