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-rw-r--r--arch/ia64/kernel/pci-dma.c129
1 files changed, 129 insertions, 0 deletions
diff --git a/arch/ia64/kernel/pci-dma.c b/arch/ia64/kernel/pci-dma.c
new file mode 100644
index 0000000..10a75b5
--- /dev/null
+++ b/arch/ia64/kernel/pci-dma.c
@@ -0,0 +1,129 @@
+/*
+ * Dynamic DMA mapping support.
+ */
+
+#include <linux/types.h>
+#include <linux/mm.h>
+#include <linux/string.h>
+#include <linux/pci.h>
+#include <linux/module.h>
+#include <linux/dmar.h>
+#include <asm/iommu.h>
+#include <asm/machvec.h>
+#include <linux/dma-mapping.h>
+
+#include <asm/machvec.h>
+#include <asm/system.h>
+
+#ifdef CONFIG_DMAR
+
+#include <linux/kernel.h>
+#include <linux/string.h>
+
+#include <asm/page.h>
+#include <asm/iommu.h>
+
+dma_addr_t bad_dma_address __read_mostly;
+EXPORT_SYMBOL(bad_dma_address);
+
+static int iommu_sac_force __read_mostly;
+
+int no_iommu __read_mostly;
+#ifdef CONFIG_IOMMU_DEBUG
+int force_iommu __read_mostly = 1;
+#else
+int force_iommu __read_mostly;
+#endif
+
+/* Set this to 1 if there is a HW IOMMU in the system */
+int iommu_detected __read_mostly;
+
+/* Dummy device used for NULL arguments (normally ISA). Better would
+ be probably a smaller DMA mask, but this is bug-to-bug compatible
+ to i386. */
+struct device fallback_dev = {
+ .bus_id = "fallback device",
+ .coherent_dma_mask = DMA_32BIT_MASK,
+ .dma_mask = &fallback_dev.coherent_dma_mask,
+};
+
+void __init pci_iommu_alloc(void)
+{
+ /*
+ * The order of these functions is important for
+ * fall-back/fail-over reasons
+ */
+ detect_intel_iommu();
+
+#ifdef CONFIG_SWIOTLB
+ pci_swiotlb_init();
+#endif
+}
+
+static int __init pci_iommu_init(void)
+{
+ if (iommu_detected)
+ intel_iommu_init();
+
+ return 0;
+}
+
+/* Must execute after PCI subsystem */
+fs_initcall(pci_iommu_init);
+
+void pci_iommu_shutdown(void)
+{
+ return;
+}
+
+void __init
+iommu_dma_init(void)
+{
+ return;
+}
+
+struct dma_mapping_ops *dma_ops;
+EXPORT_SYMBOL(dma_ops);
+
+int iommu_dma_supported(struct device *dev, u64 mask)
+{
+ struct dma_mapping_ops *ops = get_dma_ops(dev);
+
+#ifdef CONFIG_PCI
+ if (mask > 0xffffffff && forbid_dac > 0) {
+ dev_info(dev, "Disallowing DAC for device\n");
+ return 0;
+ }
+#endif
+
+ if (ops->dma_supported_op)
+ return ops->dma_supported_op(dev, mask);
+
+ /* Copied from i386. Doesn't make much sense, because it will
+ only work for pci_alloc_coherent.
+ The caller just has to use GFP_DMA in this case. */
+ if (mask < DMA_24BIT_MASK)
+ return 0;
+
+ /* Tell the device to use SAC when IOMMU force is on. This
+ allows the driver to use cheaper accesses in some cases.
+
+ Problem with this is that if we overflow the IOMMU area and
+ return DAC as fallback address the device may not handle it
+ correctly.
+
+ As a special case some controllers have a 39bit address
+ mode that is as efficient as 32bit (aic79xx). Don't force
+ SAC for these. Assume all masks <= 40 bits are of this
+ type. Normally this doesn't make any difference, but gives
+ more gentle handling of IOMMU overflow. */
+ if (iommu_sac_force && (mask >= DMA_40BIT_MASK)) {
+ dev_info(dev, "Force SAC with mask %lx\n", mask);
+ return 0;
+ }
+
+ return 1;
+}
+EXPORT_SYMBOL(iommu_dma_supported);
+
+#endif