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authorAndy Shevchenko <andriy.shevchenko@linux.intel.com>2019-05-14 15:43:05 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2019-05-14 19:52:49 -0700
commit2c64e9cb0b6b858901e9a386860d7d929d1cbaeb (patch)
tree749da0ef8f5d478680a523c877fb0e16fc18409c /lib/div64.c
parentb5c56e0cdd62979dd538e5363b06be5bdf735a09 (diff)
lib: Move mathematic helpers to separate folder
For better maintenance and expansion move the mathematic helpers to the separate folder. No functional change intended. Note, the int_sqrt() is not used as a part of lib, so, moved to regular obj. Link: http://lkml.kernel.org/r/20190323172531.80025-1-andriy.shevchenko@linux.intel.com Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Lee Jones <lee.jones@linaro.org> Cc: Daniel Thompson <daniel.thompson@linaro.org> Cc: Ray Jui <rjui@broadcom.com> [mchehab+samsung@kernel.org: fix broken doc references for div64.c and gcd.c] Link: http://lkml.kernel.org/r/734f49bae5d4052b3c25691dfefad59bea2e5843.1555580999.git.mchehab+samsung@kernel.org Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'lib/div64.c')
-rw-r--r--lib/div64.c192
1 files changed, 0 insertions, 192 deletions
diff --git a/lib/div64.c b/lib/div64.c
deleted file mode 100644
index ee146bb4c558..000000000000
--- a/lib/div64.c
+++ /dev/null
@@ -1,192 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- * Copyright (C) 2003 Bernardo Innocenti <bernie@develer.com>
- *
- * Based on former do_div() implementation from asm-parisc/div64.h:
- * Copyright (C) 1999 Hewlett-Packard Co
- * Copyright (C) 1999 David Mosberger-Tang <davidm@hpl.hp.com>
- *
- *
- * Generic C version of 64bit/32bit division and modulo, with
- * 64bit result and 32bit remainder.
- *
- * The fast case for (n>>32 == 0) is handled inline by do_div().
- *
- * Code generated for this function might be very inefficient
- * for some CPUs. __div64_32() can be overridden by linking arch-specific
- * assembly versions such as arch/ppc/lib/div64.S and arch/sh/lib/div64.S
- * or by defining a preprocessor macro in arch/include/asm/div64.h.
- */
-
-#include <linux/export.h>
-#include <linux/kernel.h>
-#include <linux/math64.h>
-
-/* Not needed on 64bit architectures */
-#if BITS_PER_LONG == 32
-
-#ifndef __div64_32
-uint32_t __attribute__((weak)) __div64_32(uint64_t *n, uint32_t base)
-{
- uint64_t rem = *n;
- uint64_t b = base;
- uint64_t res, d = 1;
- uint32_t high = rem >> 32;
-
- /* Reduce the thing a bit first */
- res = 0;
- if (high >= base) {
- high /= base;
- res = (uint64_t) high << 32;
- rem -= (uint64_t) (high*base) << 32;
- }
-
- while ((int64_t)b > 0 && b < rem) {
- b = b+b;
- d = d+d;
- }
-
- do {
- if (rem >= b) {
- rem -= b;
- res += d;
- }
- b >>= 1;
- d >>= 1;
- } while (d);
-
- *n = res;
- return rem;
-}
-EXPORT_SYMBOL(__div64_32);
-#endif
-
-/**
- * div_s64_rem - signed 64bit divide with 64bit divisor and remainder
- * @dividend: 64bit dividend
- * @divisor: 64bit divisor
- * @remainder: 64bit remainder
- */
-#ifndef div_s64_rem
-s64 div_s64_rem(s64 dividend, s32 divisor, s32 *remainder)
-{
- u64 quotient;
-
- if (dividend < 0) {
- quotient = div_u64_rem(-dividend, abs(divisor), (u32 *)remainder);
- *remainder = -*remainder;
- if (divisor > 0)
- quotient = -quotient;
- } else {
- quotient = div_u64_rem(dividend, abs(divisor), (u32 *)remainder);
- if (divisor < 0)
- quotient = -quotient;
- }
- return quotient;
-}
-EXPORT_SYMBOL(div_s64_rem);
-#endif
-
-/**
- * div64_u64_rem - unsigned 64bit divide with 64bit divisor and remainder
- * @dividend: 64bit dividend
- * @divisor: 64bit divisor
- * @remainder: 64bit remainder
- *
- * This implementation is a comparable to algorithm used by div64_u64.
- * But this operation, which includes math for calculating the remainder,
- * is kept distinct to avoid slowing down the div64_u64 operation on 32bit
- * systems.
- */
-#ifndef div64_u64_rem
-u64 div64_u64_rem(u64 dividend, u64 divisor, u64 *remainder)
-{
- u32 high = divisor >> 32;
- u64 quot;
-
- if (high == 0) {
- u32 rem32;
- quot = div_u64_rem(dividend, divisor, &rem32);
- *remainder = rem32;
- } else {
- int n = fls(high);
- quot = div_u64(dividend >> n, divisor >> n);
-
- if (quot != 0)
- quot--;
-
- *remainder = dividend - quot * divisor;
- if (*remainder >= divisor) {
- quot++;
- *remainder -= divisor;
- }
- }
-
- return quot;
-}
-EXPORT_SYMBOL(div64_u64_rem);
-#endif
-
-/**
- * div64_u64 - unsigned 64bit divide with 64bit divisor
- * @dividend: 64bit dividend
- * @divisor: 64bit divisor
- *
- * This implementation is a modified version of the algorithm proposed
- * by the book 'Hacker's Delight'. The original source and full proof
- * can be found here and is available for use without restriction.
- *
- * 'http://www.hackersdelight.org/hdcodetxt/divDouble.c.txt'
- */
-#ifndef div64_u64
-u64 div64_u64(u64 dividend, u64 divisor)
-{
- u32 high = divisor >> 32;
- u64 quot;
-
- if (high == 0) {
- quot = div_u64(dividend, divisor);
- } else {
- int n = fls(high);
- quot = div_u64(dividend >> n, divisor >> n);
-
- if (quot != 0)
- quot--;
- if ((dividend - quot * divisor) >= divisor)
- quot++;
- }
-
- return quot;
-}
-EXPORT_SYMBOL(div64_u64);
-#endif
-
-/**
- * div64_s64 - signed 64bit divide with 64bit divisor
- * @dividend: 64bit dividend
- * @divisor: 64bit divisor
- */
-#ifndef div64_s64
-s64 div64_s64(s64 dividend, s64 divisor)
-{
- s64 quot, t;
-
- quot = div64_u64(abs(dividend), abs(divisor));
- t = (dividend ^ divisor) >> 63;
-
- return (quot ^ t) - t;
-}
-EXPORT_SYMBOL(div64_s64);
-#endif
-
-#endif /* BITS_PER_LONG == 32 */
-
-/*
- * Iterative div/mod for use when dividend is not expected to be much
- * bigger than divisor.
- */
-u32 iter_div_u64_rem(u64 dividend, u32 divisor, u64 *remainder)
-{
- return __iter_div_u64_rem(dividend, divisor, remainder);
-}
-EXPORT_SYMBOL(iter_div_u64_rem);