diff options
Diffstat (limited to 'arch/arm64/lib/bitops.S')
-rw-r--r-- | arch/arm64/lib/bitops.S | 68 |
1 files changed, 68 insertions, 0 deletions
diff --git a/arch/arm64/lib/bitops.S b/arch/arm64/lib/bitops.S new file mode 100644 index 000000000000..e5db797790d3 --- /dev/null +++ b/arch/arm64/lib/bitops.S @@ -0,0 +1,68 @@ +/* + * 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 31:6 word offset + * x1: address + */ + .macro bitop, name, instr +ENTRY( \name ) + and w3, w0, #63 // Get bit offset + eor w0, w0, w3 // 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 w3, w0, #63 // Get bit offset + eor w0, w0, w3 // Clear low bits + mov x2, #1 + add x1, x1, x0, lsr #3 // Get word offset + lsl x4, x2, x3 // Create mask +1: ldaxr x2, [x1] + lsr x0, x2, x3 // Save old value of bit + \instr x2, x2, x4 // toggle bit + stlxr w5, x2, [x1] + cbnz w5, 1b + 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 |