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authorYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 12:17:53 -0700
committerYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 15:44:42 -0700
commit9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch)
tree1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/arch/arm64/lib/bitops.S
parent98260f3884f4a202f9ca5eabed40b1354c489b29 (diff)
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/arch/arm64/lib/bitops.S')
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1 files changed, 69 insertions, 0 deletions
diff --git a/kernel/arch/arm64/lib/bitops.S b/kernel/arch/arm64/lib/bitops.S
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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 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: ldxr x2, [x1]
+ lsr x0, x2, x3 // Save old value of bit
+ \instr x2, x2, x4 // toggle bit
+ stlxr w5, x2, [x1]
+ cbnz w5, 1b
+ 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