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Subject[x86 setup 15/33] Simple bitops for the new x86 setup code.
Date
From: H. Peter Anvin <hpa@zytor.com>

A simple collection of bitops for the new x86 setup code.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
---
arch/i386/boot/bitops.h | 45 +++++++++++++++++++++++++++++++++++++++++++++
1 files changed, 45 insertions(+), 0 deletions(-)
create mode 100644 arch/i386/boot/bitops.h
diff --git a/arch/i386/boot/bitops.h b/arch/i386/boot/bitops.h
new file mode 100644
index 0000000..8dcc8dc
--- /dev/null
+++ b/arch/i386/boot/bitops.h
@@ -0,0 +1,45 @@
+/* -*- linux-c -*- ------------------------------------------------------- *
+ *
+ * Copyright (C) 1991, 1992 Linus Torvalds
+ * Copyright 2007 rPath, Inc. - All Rights Reserved
+ *
+ * This file is part of the Linux kernel, and is made available under
+ * the terms of the GNU General Public License version 2.
+ *
+ * ----------------------------------------------------------------------- */
+
+/*
+ * arch/i386/boot/bitops.h
+ *
+ * Very simple bitops for the boot code.
+ */
+
+#ifndef BOOT_BITOPS_H
+#define BOOT_BITOPS_H
+#define _LINUX_BITOPS_H /* Inhibit inclusion of <linux/bitops.h> */
+
+static inline int constant_test_bit(int nr, const void *addr)
+{
+ const u32 *p = (const u32 *)addr;
+ return ((1UL << (nr & 31)) & (p[nr >> 5])) != 0;
+}
+static inline int variable_test_bit(int nr, const void *addr)
+{
+ u8 v;
+ const u32 *p = (const u32 *)addr;
+
+ asm("btl %2,%1; setc %0" : "=qm" (v) : "m" (*p), "Ir" (nr));
+ return v;
+}
+
+#define test_bit(nr,addr) \
+(__builtin_constant_p(nr) ? \
+ constant_test_bit((nr),(addr)) : \
+ variable_test_bit((nr),(addr)))
+
+static inline void set_bit(int nr, void *addr)
+{
+ asm("btsl %1,%0" : "+m" (*(u32 *)addr) : "Ir" (nr));
+}
+
+#endif /* BOOT_BITOPS_H */
--
1.5.2.2
-
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