1 files changed, 39 insertions, 0 deletions

diff --git a/arch/arm64/lib/clear_page.S b/arch/arm64/lib/clear_page.S
new file mode 100644
index 000000000000..ef08e905e35b
--- /dev/null
+++ b/arch/arm64/lib/clear_page.S
@@ -0,0 +1,39 @@
+/*
+ * Copyright (C) 2012 ARM Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/linkage.h>
+#include <linux/const.h>
+#include <asm/assembler.h>
+#include <asm/page.h>
+
+/*
+ * Clear page @dest
+ *
+ * Parameters:
+ *      x0 - dest
+ */
+ENTRY(clear_page)
+        mrs     x1, dczid_el0
+        and     w1, w1, #0xf
+        mov     x2, #4
+        lsl     x1, x2, x1
+
+1:      dc      zva, x0
+        add     x0, x0, x1
+        tst     x0, #(PAGE_SIZE - 1)
+        b.ne    1b
+        ret
+ENDPROC(clear_page)