1 files changed, 32 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/i915_memcpy.h b/drivers/gpu/drm/i915/i915_memcpy.h
new file mode 100644
index 000000000000..970d84b16987
--- /dev/null
+++ b/drivers/gpu/drm/i915/i915_memcpy.h
@@ -0,0 +1,32 @@
+/* SPDX-License-Identifier: MIT */
+/*
+ * Copyright © 2019 Intel Corporation
+ */
+
+#ifndef __I915_MEMCPY_H__
+#define __I915_MEMCPY_H__
+
+#include <linux/types.h>
+
+struct drm_i915_private;
+
+void i915_memcpy_init_early(struct drm_i915_private *i915);
+bool i915_memcpy_from_wc(void *dst, const void *src, unsigned long len);
+
+/* The movntdqa instructions used for memcpy-from-wc require 16-byte alignment,
+ * as well as SSE4.1 support. i915_memcpy_from_wc() will report if it cannot
+ * perform the operation. To check beforehand, pass in the parameters to
+ * to i915_can_memcpy_from_wc() - since we only care about the low 4 bits,
+ * you only need to pass in the minor offsets, page-aligned pointers are
+ * always valid.
+ *
+ * For just checking for SSE4.1, in the foreknowledge that the future use
+ * will be correctly aligned, just use i915_has_memcpy_from_wc().
+ */
+#define i915_can_memcpy_from_wc(dst, src, len) \
+	i915_memcpy_from_wc((void *)((unsigned long)(dst) | (unsigned long)(src) | (len)), NULL, 0)
+
+#define i915_has_memcpy_from_wc() \
+	i915_memcpy_from_wc(NULL, NULL, 0)
+
+#endif /* __I915_MEMCPY_H__ */