From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from 8.mo5.mail-out.ovh.net ([178.32.116.78] helo=mo5.mail-out.ovh.net) by merlin.infradead.org with esmtp (Exim 4.76 #1 (Red Hat Linux)) id 1TNVA2-0003ut-FQ for barebox@lists.infradead.org; Sun, 14 Oct 2012 20:51:47 +0000 Received: from mail619.ha.ovh.net (b7.ovh.net [213.186.33.57]) by mo5.mail-out.ovh.net (Postfix) with SMTP id 2AF61FF94E8 for ; Sun, 14 Oct 2012 22:58:22 +0200 (CEST) From: Jean-Christophe PLAGNIOL-VILLARD Date: Sun, 14 Oct 2012 22:49:22 +0200 Message-Id: <1350247764-18132-1-git-send-email-plagnioj@jcrosoft.com> In-Reply-To: <20121014204622.GT13639@game.jcrosoft.org> References: <20121014204622.GT13639@game.jcrosoft.org> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: barebox-bounces@lists.infradead.org Errors-To: barebox-bounces+u.kleine-koenig=pengutronix.de@lists.infradead.org Subject: [PATCH 1/3] import include/linux/math64.h To: barebox@lists.infradead.org need by mtd_dataflash Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD --- include/linux/math64.h | 121 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 121 insertions(+) create mode 100644 include/linux/math64.h diff --git a/include/linux/math64.h b/include/linux/math64.h new file mode 100644 index 0000000..71dd6d7 --- /dev/null +++ b/include/linux/math64.h @@ -0,0 +1,121 @@ +#ifndef _LINUX_MATH64_H +#define _LINUX_MATH64_H + +#include +#include + +#if BITS_PER_LONG == 64 + +#define div64_long(x,y) div64_s64((x),(y)) + +/** + * div_u64_rem - unsigned 64bit divide with 32bit divisor with remainder + * + * This is commonly provided by 32bit archs to provide an optimized 64bit + * divide. + */ +static inline u64 div_u64_rem(u64 dividend, u32 divisor, u32 *remainder) +{ + *remainder = dividend % divisor; + return dividend / divisor; +} + +/** + * div_s64_rem - signed 64bit divide with 32bit divisor with remainder + */ +static inline s64 div_s64_rem(s64 dividend, s32 divisor, s32 *remainder) +{ + *remainder = dividend % divisor; + return dividend / divisor; +} + +/** + * div64_u64 - unsigned 64bit divide with 64bit divisor + */ +static inline u64 div64_u64(u64 dividend, u64 divisor) +{ + return dividend / divisor; +} + +/** + * div64_s64 - signed 64bit divide with 64bit divisor + */ +static inline s64 div64_s64(s64 dividend, s64 divisor) +{ + return dividend / divisor; +} + +#elif BITS_PER_LONG == 32 + +#define div64_long(x,y) div_s64((x),(y)) + +#ifndef div_u64_rem +static inline u64 div_u64_rem(u64 dividend, u32 divisor, u32 *remainder) +{ + *remainder = do_div(dividend, divisor); + return dividend; +} +#endif + +#ifndef div_s64_rem +extern s64 div_s64_rem(s64 dividend, s32 divisor, s32 *remainder); +#endif + +#ifndef div64_u64 +extern u64 div64_u64(u64 dividend, u64 divisor); +#endif + +#ifndef div64_s64 +extern s64 div64_s64(s64 dividend, s64 divisor); +#endif + +#endif /* BITS_PER_LONG */ + +/** + * div_u64 - unsigned 64bit divide with 32bit divisor + * + * This is the most common 64bit divide and should be used if possible, + * as many 32bit archs can optimize this variant better than a full 64bit + * divide. + */ +#ifndef div_u64 +static inline u64 div_u64(u64 dividend, u32 divisor) +{ + u32 remainder; + return div_u64_rem(dividend, divisor, &remainder); +} +#endif + +/** + * div_s64 - signed 64bit divide with 32bit divisor + */ +#ifndef div_s64 +static inline s64 div_s64(s64 dividend, s32 divisor) +{ + s32 remainder; + return div_s64_rem(dividend, divisor, &remainder); +} +#endif + +u32 iter_div_u64_rem(u64 dividend, u32 divisor, u64 *remainder); + +static __always_inline u32 +__iter_div_u64_rem(u64 dividend, u32 divisor, u64 *remainder) +{ + u32 ret = 0; + + while (dividend >= divisor) { + /* The following asm() prevents the compiler from + optimising this loop into a modulo operation. */ + asm("" : "+rm"(dividend)); + + dividend -= divisor; + ret++; + } + + *remainder = dividend; + + return ret; +} + +#endif /* _LINUX_MATH64_H */ -- 1.7.10.4 _______________________________________________ barebox mailing list barebox@lists.infradead.org http://lists.infradead.org/mailman/listinfo/barebox