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authorMasahiro Yamada <yamada.m@jp.panasonic.com>2014-11-07 03:03:28 +0900
committerTom Rini <trini@ti.com>2014-11-20 11:28:25 -0500
commitcba1da495daa3bfa29372b5eb28cb49302ef0a72 (patch)
treef7967f55bf3cdd375aefbb3f0c124fde315a117e /include/linux/kernel.h
parent9e57a1c3ad58cfb4bdf27596a9b768f7584f1040 (diff)
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include: move various macros to include/linux/kernel.h
U-Boot has imported various utility macros from Linux scattering them to various places without consistency. In include/common.h are min, max, min3, max3, ARRAY_SIZE, ALIGN, container_of, DIV_ROUND_UP, etc. In include/linux/compat.h are min_t, max_t, round_up, round_down, etc. We also have duplicated defines of min_t in some *.c files. Moreover, we are suffering from too cluttered include/common.h. This commit moves various macros that originate in include/linux/kernel.h of Linux to their original position. Note: This commit simply moves the macros; the macros roundup, min, max, min2, max3, ARRAY_SIZE are different from those of Linux at this point. Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Diffstat (limited to 'include/linux/kernel.h')
-rw-r--r--include/linux/kernel.h157
1 files changed, 157 insertions, 0 deletions
diff --git a/include/linux/kernel.h b/include/linux/kernel.h
new file mode 100644
index 0000000..527ed40
--- /dev/null
+++ b/include/linux/kernel.h
@@ -0,0 +1,157 @@
+#ifndef _LINUX_KERNEL_H
+#define _LINUX_KERNEL_H
+
+
+#include <linux/types.h>
+
+#define INT_MAX ((int)(~0U>>1))
+#define INT_MIN (-INT_MAX - 1)
+#define LLONG_MAX ((long long)(~0ULL>>1))
+
+#define U8_MAX ((u8)~0U)
+#define U32_MAX ((u32)~0U)
+#define U64_MAX ((u64)~0ULL)
+
+#define ALIGN(x,a) __ALIGN_MASK((x),(typeof(x))(a)-1)
+#define __ALIGN_MASK(x,mask) (((x)+(mask))&~(mask))
+
+#define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
+
+/*
+ * This looks more complex than it should be. But we need to
+ * get the type for the ~ right in round_down (it needs to be
+ * as wide as the result!), and we want to evaluate the macro
+ * arguments just once each.
+ */
+#define __round_mask(x, y) ((__typeof__(x))((y)-1))
+#define round_up(x, y) ((((x)-1) | __round_mask(x, y))+1)
+#define round_down(x, y) ((x) & ~__round_mask(x, y))
+
+#define DIV_ROUND_UP(n,d) (((n) + (d) - 1) / (d))
+
+#define roundup(x, y) ((((x) + ((y) - 1)) / (y)) * (y))
+
+/*
+ * Divide positive or negative dividend by positive divisor and round
+ * to closest integer. Result is undefined for negative divisors and
+ * for negative dividends if the divisor variable type is unsigned.
+ */
+#define DIV_ROUND_CLOSEST(x, divisor)( \
+{ \
+ typeof(x) __x = x; \
+ typeof(divisor) __d = divisor; \
+ (((typeof(x))-1) > 0 || \
+ ((typeof(divisor))-1) > 0 || (__x) > 0) ? \
+ (((__x) + ((__d) / 2)) / (__d)) : \
+ (((__x) - ((__d) / 2)) / (__d)); \
+} \
+)
+
+/*
+ * Multiplies an integer by a fraction, while avoiding unnecessary
+ * overflow or loss of precision.
+ */
+#define mult_frac(x, numer, denom)( \
+{ \
+ typeof(x) quot = (x) / (denom); \
+ typeof(x) rem = (x) % (denom); \
+ (quot * (numer)) + ((rem * (numer)) / (denom)); \
+} \
+)
+
+/**
+ * upper_32_bits - return bits 32-63 of a number
+ * @n: the number we're accessing
+ *
+ * A basic shift-right of a 64- or 32-bit quantity. Use this to suppress
+ * the "right shift count >= width of type" warning when that quantity is
+ * 32-bits.
+ */
+#define upper_32_bits(n) ((u32)(((n) >> 16) >> 16))
+
+/**
+ * lower_32_bits - return bits 0-31 of a number
+ * @n: the number we're accessing
+ */
+#define lower_32_bits(n) ((u32)(n))
+
+/*
+ * abs() handles unsigned and signed longs, ints, shorts and chars. For all
+ * input types abs() returns a signed long.
+ * abs() should not be used for 64-bit types (s64, u64, long long) - use abs64()
+ * for those.
+ */
+#define abs(x) ({ \
+ long ret; \
+ if (sizeof(x) == sizeof(long)) { \
+ long __x = (x); \
+ ret = (__x < 0) ? -__x : __x; \
+ } else { \
+ int __x = (x); \
+ ret = (__x < 0) ? -__x : __x; \
+ } \
+ ret; \
+ })
+
+#define abs64(x) ({ \
+ s64 __x = (x); \
+ (__x < 0) ? -__x : __x; \
+ })
+
+/*
+ * min()/max()/clamp() macros that also do
+ * strict type-checking.. See the
+ * "unnecessary" pointer comparison.
+ */
+#define min(x, y) ({ \
+ typeof(x) _min1 = (x); \
+ typeof(y) _min2 = (y); \
+ _min1 < _min2 ? _min1 : _min2; })
+
+#define max(x, y) ({ \
+ typeof(x) _max1 = (x); \
+ typeof(y) _max2 = (y); \
+ _max1 > _max2 ? _max1 : _max2; })
+
+#define min3(x, y, z) ({ \
+ typeof(x) _min1 = (x); \
+ typeof(y) _min2 = (y); \
+ typeof(z) _min3 = (z); \
+ _min1 < _min2 ? (_min1 < _min3 ? _min1 : _min3) : \
+ (_min2 < _min3 ? _min2 : _min3); })
+
+#define max3(x, y, z) ({ \
+ typeof(x) _max1 = (x); \
+ typeof(y) _max2 = (y); \
+ typeof(z) _max3 = (z); \
+ _max1 > _max2 ? (_max1 > _max3 ? _max1 : _max3) : \
+ (_max2 > _max3 ? _max2 : _max3); })
+
+/*
+ * ..and if you can't take the strict
+ * types, you can specify one yourself.
+ *
+ * Or not use min/max/clamp at all, of course.
+ */
+#define min_t(type, x, y) ({ \
+ type __min1 = (x); \
+ type __min2 = (y); \
+ __min1 < __min2 ? __min1: __min2; })
+
+#define max_t(type, x, y) ({ \
+ type __max1 = (x); \
+ type __max2 = (y); \
+ __max1 > __max2 ? __max1: __max2; })
+
+/**
+ * container_of - cast a member of a structure out to the containing structure
+ * @ptr: the pointer to the member.
+ * @type: the type of the container struct this is embedded in.
+ * @member: the name of the member within the struct.
+ *
+ */
+#define container_of(ptr, type, member) ({ \
+ const typeof( ((type *)0)->member ) *__mptr = (ptr); \
+ (type *)( (char *)__mptr - offsetof(type,member) );})
+
+#endif