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+/*
+ * Based on arch/arm/lib/bitops.h
+ *
+ * Copyright (C) 2013 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 <asm/assembler.h>
+
+/*
+ * x0: bits 5:0 bit offset
+ * bits 63:6 word offset
+ * x1: address
+ */
+ .macro bitop, name, instr
+ENTRY( \name )
+ and x3, x0, #63 // Get bit offset
+ eor x0, x0, x3 // Clear low bits
+ mov x2, #1
+ add x1, x1, x0, lsr #3 // Get word offset
+ lsl x3, x2, x3 // Create mask
+1: ldxr x2, [x1]
+ \instr x2, x2, x3
+ stxr w0, x2, [x1]
+ cbnz w0, 1b
+ ret
+ENDPROC(\name )
+ .endm
+
+ .macro testop, name, instr
+ENTRY( \name )
+ and x3, x0, #63 // Get bit offset
+ eor x0, x0, x3 // Clear low bits
+ mov x2, #1
+ add x1, x1, x0, lsr #3 // Get word offset
+ lsl x4, x2, x3 // Create mask
+ smp_dmb ish
+1: ldxr x2, [x1]
+ lsr x0, x2, x3 // Save old value of bit
+ \instr x2, x2, x4 // toggle bit
+ stxr w2, x2, [x1]
+ cbnz w2, 1b
+ smp_dmb ish
+ and x0, x0, #1
+3: ret
+ENDPROC(\name )
+ .endm
+
+/*
+ * Atomic bit operations.
+ */
+ bitop change_bit, eor
+ bitop clear_bit, bic
+ bitop set_bit, orr
+
+ testop test_and_change_bit, eor
+ testop test_and_clear_bit, bic
+ testop test_and_set_bit, orr