Fixed MTP to work with TWRP

arch/ia64/kernel/pci-dma.c

@@ -0,0 +1,110 @@
+/*
+ * 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>
+
+
+#ifdef CONFIG_INTEL_IOMMU
+
+#include <linux/kernel.h>
+
+#include <asm/page.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
+
+int iommu_pass_through;
+
+extern struct dma_map_ops intel_dma_ops;
+
+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;
+}
+
+int iommu_dma_supported(struct device *dev, u64 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_BIT_MASK(24))
+		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_BIT_MASK(40))) {
+		dev_info(dev, "Force SAC with mask %llx\n", mask);
+		return 0;
+	}
+
+	return 1;
+}
+EXPORT_SYMBOL(iommu_dma_supported);
+
+void __init pci_iommu_alloc(void)
+{
+	dma_ops = &intel_dma_ops;
+
+	dma_ops->sync_single_for_cpu = machvec_dma_sync_single;
+	dma_ops->sync_sg_for_cpu = machvec_dma_sync_sg;
+	dma_ops->sync_single_for_device = machvec_dma_sync_single;
+	dma_ops->sync_sg_for_device = machvec_dma_sync_sg;
+	dma_ops->dma_supported = iommu_dma_supported;
+
+	/*
+	 * The order of these functions is important for
+	 * fall-back/fail-over reasons
+	 */
+	detect_intel_iommu();
+
+#ifdef CONFIG_SWIOTLB
+	pci_swiotlb_init();
+#endif
+}
+
+#endif