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authorThomas Hellström <thomas.hellstrom@linux.intel.com>2025-12-19 11:51:22 +0100
committerThomas Hellström <thomas.hellstrom@linux.intel.com>2025-12-19 11:51:22 +0100
commit5add3c3c280a35f7e258e9cef7607db5a2e56fdc (patch)
tree22eca9a4a1003a64933980bf76da2fbe8a74f759 /include/linux/math64.h
parentc7b83a916d62c4d4447d7edf0bc5e06dc2afbdf8 (diff)
parent8f0b4cce4481fb22653697cced8d0d04027cb1e8 (diff)
Merge drm/drm-next into drm-xe-next
Backmerging to bring in 6.19-rc1. An important upstream bugfix and to help unblock PTL CI. Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Diffstat (limited to 'include/linux/math64.h')
-rw-r--r--include/linux/math64.h59
1 files changed, 58 insertions, 1 deletions
diff --git a/include/linux/math64.h b/include/linux/math64.h
index 6aaccc1626ab..cc305206d89f 100644
--- a/include/linux/math64.h
+++ b/include/linux/math64.h
@@ -158,6 +158,17 @@ static inline u64 mul_u32_u32(u32 a, u32 b)
}
#endif
+#ifndef add_u64_u32
+/*
+ * Many a GCC version also messes this up.
+ * Zero extending b and then spilling everything to stack.
+ */
+static inline u64 add_u64_u32(u64 a, u32 b)
+{
+ return a + b;
+}
+#endif
+
#if defined(CONFIG_ARCH_SUPPORTS_INT128) && defined(__SIZEOF_INT128__)
#ifndef mul_u64_u32_shr
@@ -282,7 +293,53 @@ static inline u64 mul_u64_u32_div(u64 a, u32 mul, u32 divisor)
}
#endif /* mul_u64_u32_div */
-u64 mul_u64_u64_div_u64(u64 a, u64 mul, u64 div);
+/**
+ * mul_u64_add_u64_div_u64 - unsigned 64bit multiply, add, and divide
+ * @a: first unsigned 64bit multiplicand
+ * @b: second unsigned 64bit multiplicand
+ * @c: unsigned 64bit addend
+ * @d: unsigned 64bit divisor
+ *
+ * Multiply two 64bit values together to generate a 128bit product
+ * add a third value and then divide by a fourth.
+ * The Generic code divides by 0 if @d is zero and returns ~0 on overflow.
+ * Architecture specific code may trap on zero or overflow.
+ *
+ * Return: (@a * @b + @c) / @d
+ */
+u64 mul_u64_add_u64_div_u64(u64 a, u64 b, u64 c, u64 d);
+
+/**
+ * mul_u64_u64_div_u64 - unsigned 64bit multiply and divide
+ * @a: first unsigned 64bit multiplicand
+ * @b: second unsigned 64bit multiplicand
+ * @d: unsigned 64bit divisor
+ *
+ * Multiply two 64bit values together to generate a 128bit product
+ * and then divide by a third value.
+ * The Generic code divides by 0 if @d is zero and returns ~0 on overflow.
+ * Architecture specific code may trap on zero or overflow.
+ *
+ * Return: @a * @b / @d
+ */
+#define mul_u64_u64_div_u64(a, b, d) mul_u64_add_u64_div_u64(a, b, 0, d)
+
+/**
+ * mul_u64_u64_div_u64_roundup - unsigned 64bit multiply and divide rounded up
+ * @a: first unsigned 64bit multiplicand
+ * @b: second unsigned 64bit multiplicand
+ * @d: unsigned 64bit divisor
+ *
+ * Multiply two 64bit values together to generate a 128bit product
+ * and then divide and round up.
+ * The Generic code divides by 0 if @d is zero and returns ~0 on overflow.
+ * Architecture specific code may trap on zero or overflow.
+ *
+ * Return: (@a * @b + @d - 1) / @d
+ */
+#define mul_u64_u64_div_u64_roundup(a, b, d) \
+ ({ u64 _tmp = (d); mul_u64_add_u64_div_u64(a, b, _tmp - 1, _tmp); })
+
/**
* DIV64_U64_ROUND_UP - unsigned 64bit divide with 64bit divisor rounded up