X-Git-Url: http://review.tizen.org/git/?a=blobdiff_plain;ds=sidebyside;f=lib%2Fdiv64.c;h=4382ad77777ebcb17bc4b25fe606f4371b563a5d;hb=e3c55d406bd8df1a878546002c93db90c42be10c;hp=a163b6caef73fdc26e19f8d18ef66604a03b1cf8;hpb=645a992934c8007fa17ac2e512ce73c100ed1614;p=platform%2Fkernel%2Flinux-starfive.git

diff --git a/lib/div64.c b/lib/div64.c
index a163b6c..4382ad7 100644
--- a/lib/div64.c
+++ b/lib/div64.c
@@ -79,6 +79,46 @@ 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 = 1 + 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