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authorTerry Lv <r65388@freescale.com>2009-12-10 11:26:52 +0800
committerTerry Lv <r65388@freescale.com>2009-12-11 12:44:24 +0800
commit1ee27e13d6fdb19d297f8d1d6d3d7d8449d0361e (patch)
tree90de615a82637ea82d8f81914ea6a5249b85512b /include/linux/bitops.h
parent270ba8ac5b8c52a0b4fcf0d77eb66ac647c7f37c (diff)
downloadu-boot-imx-1ee27e13d6fdb19d297f8d1d6d3d7d8449d0361e.zip
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ENGR00119171: ubifs support for android recovery mode.
ubifs support for android recovery mode. Signed-off-by: Terry Lv <r65388@freescale.com>
Diffstat (limited to 'include/linux/bitops.h')
-rw-r--r--include/linux/bitops.h83
1 files changed, 83 insertions, 0 deletions
diff --git a/include/linux/bitops.h b/include/linux/bitops.h
index 7d41ae6..e724310 100644
--- a/include/linux/bitops.h
+++ b/include/linux/bitops.h
@@ -1,6 +1,7 @@
#ifndef _LINUX_BITOPS_H
#define _LINUX_BITOPS_H
+#include <asm/types.h>
/*
* ffs: find first bit set. This is defined the same way as
@@ -37,6 +38,43 @@ static inline int generic_ffs(int x)
return r;
}
+/**
+ * fls - find last (most-significant) bit set
+ * @x: the word to search
+ *
+ * This is defined the same way as ffs.
+ * Note fls(0) = 0, fls(1) = 1, fls(0x80000000) = 32.
+ */
+static inline int generic_fls(int x)
+{
+ int r = 32;
+
+ if (!x)
+ return 0;
+ if (!(x & 0xffff0000u)) {
+ x <<= 16;
+ r -= 16;
+ }
+ if (!(x & 0xff000000u)) {
+ x <<= 8;
+ r -= 8;
+ }
+ if (!(x & 0xf0000000u)) {
+ x <<= 4;
+ r -= 4;
+ }
+ if (!(x & 0xc0000000u)) {
+ x <<= 2;
+ r -= 2;
+ }
+ if (!(x & 0x80000000u)) {
+ x <<= 1;
+ r -= 1;
+ }
+ return r;
+}
+
+
/*
* hweightN: returns the hamming weight (i.e. the number
* of bits set) of a N-bit word
@@ -66,7 +104,52 @@ static inline unsigned int generic_hweight8(unsigned int w)
return (res & 0x0F) + ((res >> 4) & 0x0F);
}
+#define BIT_MASK(nr) (1UL << ((nr) % BITS_PER_LONG))
+#define BIT_WORD(nr) ((nr) / BITS_PER_LONG)
+
#include <asm/bitops.h>
+/* linux/include/asm-generic/bitops/non-atomic.h */
+
+#ifndef PLATFORM__SET_BIT
+# define __set_bit generic_set_bit
+#endif
+
+#ifndef PLATFORM__CLEAR_BIT
+# define __clear_bit generic_clear_bit
+#endif
+
+#ifndef PLATFORM_FFS
+# define ffs generic_ffs
+#endif
+
+#ifndef PLATFORM_FLS
+# define fls generic_fls
+#endif
+
+/**
+ * __set_bit - Set a bit in memory
+ * @nr: the bit to set
+ * @addr: the address to start counting from
+ *
+ * Unlike set_bit(), this function is non-atomic and may be reordered.
+ * If it's called on the same region of memory simultaneously, the effect
+ * may be that only one operation succeeds.
+ */
+static inline void generic_set_bit(int nr, volatile unsigned long *addr)
+{
+ unsigned long mask = BIT_MASK(nr);
+ unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
+
+ *p |= mask;
+}
+
+static inline void generic_clear_bit(int nr, volatile unsigned long *addr)
+{
+ unsigned long mask = BIT_MASK(nr);
+ unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
+
+ *p &= ~mask;
+}
#endif