diff options
author | Masahiro Yamada <yamada.m@jp.panasonic.com> | 2014-11-07 03:03:28 +0900 |
---|---|---|
committer | Tom Rini <trini@ti.com> | 2014-11-20 11:28:25 -0500 |
commit | cba1da495daa3bfa29372b5eb28cb49302ef0a72 (patch) | |
tree | f7967f55bf3cdd375aefbb3f0c124fde315a117e /include/linux/kernel.h | |
parent | 9e57a1c3ad58cfb4bdf27596a9b768f7584f1040 (diff) | |
download | u-boot-imx-cba1da495daa3bfa29372b5eb28cb49302ef0a72.zip u-boot-imx-cba1da495daa3bfa29372b5eb28cb49302ef0a72.tar.gz u-boot-imx-cba1da495daa3bfa29372b5eb28cb49302ef0a72.tar.bz2 |
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.h | 157 |
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 |