1 files changed, 59 insertions, 0 deletions
diff --git a/arch/arm64/mm/dma-mapping.c b/arch/arm64/mm/dma-mapping.c
new file mode 100644
index 000000000..7f6f2f40d
--- /dev/null
+++ b/arch/arm64/mm/dma-mapping.c
@@ -0,0 +1,59 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2012 ARM Ltd.
+ * Author: Catalin Marinas <catalin.marinas@arm.com>
+ */
+
+#include <linux/gfp.h>
+#include <linux/cache.h>
+#include <linux/dma-map-ops.h>
+#include <xen/xen.h>
+
+#include <asm/cacheflush.h>
+#include <asm/xen/xen-ops.h>
+
+void arch_sync_dma_for_device(phys_addr_t paddr, size_t size,
+			      enum dma_data_direction dir)
+{
+	unsigned long start = (unsigned long)phys_to_virt(paddr);
+
+	dcache_clean_poc_nosync(start, start + size);
+}
+
+void arch_sync_dma_for_cpu(phys_addr_t paddr, size_t size,
+			   enum dma_data_direction dir)
+{
+	unsigned long start = (unsigned long)phys_to_virt(paddr);
+
+	if (dir == DMA_TO_DEVICE)
+		return;
+
+	dcache_inval_poc_nosync(start, start + size);
+}
+
+void arch_dma_prep_coherent(struct page *page, size_t size)
+{
+	unsigned long start = (unsigned long)page_address(page);
+
+	dcache_clean_poc(start, start + size);
+}
+
+void arch_setup_dma_ops(struct device *dev, bool coherent)
+{
+	int cls = cache_line_size_of_cpu();
+
+	if (!coherent && !CLIDR_LOC(read_sysreg(clidr_el1))) {
+		dev_warn(dev, "CLIDR_EL1.LoC == 0, treating as coherent\n");
+		coherent = true;
+	}
+
+	WARN_TAINT(!coherent && cls > ARCH_DMA_MINALIGN,
+		   TAINT_CPU_OUT_OF_SPEC,
+		   "%s %s: ARCH_DMA_MINALIGN smaller than CTR_EL0.CWG (%d < %d)",
+		   dev_driver_string(dev), dev_name(dev),
+		   ARCH_DMA_MINALIGN, cls);
+
+	dev_assign_dma_coherent(dev, coherent);
+
+	xen_setup_dma_ops(dev);
+}