Re: [PATCH v3 1/5] math64: New DIV_U64_ROUND_CLOSEST helper
From: Andy Shevchenko <hidden>
Date: 2021-07-19 12:47:50
Also in:
linux-clk, linux-serial, lkml
On Sat, Jul 17, 2021 at 3:39 PM Pali Rohár [off-list ref] wrote:
Provide DIV_U64_ROUND_CLOSEST helper which uses div_u64 to perform division rounded to the closest integer using unsigned 64bit dividend and unsigned 32bit divisor.
...
+/* + * DIV_U64_ROUND_CLOSEST - unsigned 64bit divide with 32bit divisor rounded to nearest integer
+ * @dividend: unsigned 64bit dividend
Here you insist users to provide a u64 (or compatible) type.
+ * @divisor: unsigned 32bit divisor + * + * Divide unsigned 64bit dividend by unsigned 32bit divisor + * and round to closest integer. + * + * Return: dividend / divisor rounded to nearest integer + */ +#define DIV_U64_ROUND_CLOSEST(dividend, divisor) \
+ ({ u32 _tmp = (divisor); div_u64((u64)(dividend) + _tmp / 2, _tmp); })Here is the casting to u64. Why? (Yes, I have read v1 discussion and I just want to continue it here). -- With Best Regards, Andy Shevchenko _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel