1 files changed, 29 insertions, 0 deletions

diff --git a/arch/mips/lib/iomap_copy.c b/arch/mips/lib/iomap_copy.c
new file mode 100644
index 000000000..157500a09
--- /dev/null
+++ b/arch/mips/lib/iomap_copy.c
@@ -0,0 +1,29 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+#include <linux/export.h>
+#include <linux/io.h>
+
+/**
+ * __ioread64_copy - copy data from MMIO space, in 64-bit units
+ * @to: destination (must be 64-bit aligned)
+ * @from: source, in MMIO space (must be 64-bit aligned)
+ * @count: number of 64-bit quantities to copy
+ *
+ * Copy data from MMIO space to kernel space, in units of 32 or 64 bits at a
+ * time.  Order of access is not guaranteed, nor is a memory barrier
+ * performed afterwards.
+ */
+void __ioread64_copy(void *to, const void __iomem *from, size_t count)
+{
+#ifdef CONFIG_64BIT
+        u64 *dst = to;
+        const u64 __iomem *src = from;
+        const u64 __iomem *end = src + count;
+
+        while (src < end)
+                *dst++ = __raw_readq(src++);
+#else
+        __ioread32_copy(to, from, count * 2);
+#endif
+}
+EXPORT_SYMBOL_GPL(__ioread64_copy);