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authorRosen Penev <rosenp@gmail.com>2026-09-27 13:35:01 -0700
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2026-10-01 11:04:53 +0200
commit8167c1f071426706c233e93ecfd13aba7d5c06c8 (patch)
tree2c0cd5f5e1cc35eadee98d49fe034f96a88856ce /include/vdso/math64.h
downloadlinux-stable-8167c1f071426706c233e93ecfd13aba7d5c06c8.tar.gz
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tty: serial: mpc52xx_uart: move static declarations up.grafted
Avoid a compilation error so that they're not used before being declared. Fixes: 4d105880666a ("tty: serial: mpc52xx_uart: add bounds check for psc_num array index") Reported-by: kernel test robot <lkp@intel.com> Closes: https://lore.kernel.org/oe-kbuild-all/202609260356.tJWbd1WU-lkp@intel.com/ Signed-off-by: Rosen Penev <rosenp@gmail.com> Link: https://patch.msgid.link/20260927203501.14105-1-rosenp@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'include/vdso/math64.h')
-rw-r--r--include/vdso/math64.h62
1 files changed, 62 insertions, 0 deletions
diff --git a/include/vdso/math64.h b/include/vdso/math64.h
new file mode 100644
index 000000000..22ae212f8
--- /dev/null
+++ b/include/vdso/math64.h
@@ -0,0 +1,62 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __VDSO_MATH64_H
+#define __VDSO_MATH64_H
+
+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;
+}
+
+#if defined(CONFIG_ARCH_SUPPORTS_INT128) && defined(__SIZEOF_INT128__)
+
+#ifndef mul_u64_u32_add_u64_shr
+static __always_inline u64 mul_u64_u32_add_u64_shr(u64 a, u32 mul, u64 b, unsigned int shift)
+{
+ return (u64)((((unsigned __int128)a * mul) + b) >> shift);
+}
+#endif /* mul_u64_u32_add_u64_shr */
+
+#else
+
+#ifndef mul_u64_u32_add_u64_shr
+#ifndef mul_u32_u32
+static inline u64 mul_u32_u32(u32 a, u32 b)
+{
+ return (u64)a * b;
+}
+#define mul_u32_u32 mul_u32_u32
+#endif
+static __always_inline u64 mul_u64_u32_add_u64_shr(u64 a, u32 mul, u64 b, unsigned int shift)
+{
+ u32 ah = a >> 32, al = a;
+ bool ovf;
+ u64 ret;
+
+ ovf = __builtin_add_overflow(mul_u32_u32(al, mul), b, &ret);
+ ret >>= shift;
+ if (ovf && shift)
+ ret += 1ULL << (64 - shift);
+ if (ah)
+ ret += mul_u32_u32(ah, mul) << (32 - shift);
+
+ return ret;
+}
+#endif /* mul_u64_u32_add_u64_shr */
+
+#endif
+
+#endif /* __VDSO_MATH64_H */