drm/i915: extract fixed point math to i915_fixed.h

Reduce bloat in one of the bigger header files. Fix some indentation
while at it. No functional changes.

v2: Add include guards (Joonas)

Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20181116120729.7580-1-jani.nikula@intel.com

1 files changed, 147 insertions, 0 deletions

diff --git a/drivers/gpu/drm/i915/i915_fixed.h b/drivers/gpu/drm/i915/i915_fixed.h
new file mode 100644
index 000000000000..c974e51c6d8b
--- /dev/null
+++ b/drivers/gpu/drm/i915/i915_fixed.h
@@ -0,0 +1,147 @@
+/* SPDX-License-Identifier: MIT */
+/*
+ * Copyright © 2018 Intel Corporation
+ */
+
+#ifndef _I915_FIXED_H_
+#define _I915_FIXED_H_
+
+typedef struct {
+	uint32_t val;
+} uint_fixed_16_16_t;
+
+#define FP_16_16_MAX ({ \
+	uint_fixed_16_16_t fp; \
+	fp.val = UINT_MAX; \
+	fp; \
+})
+
+static inline bool is_fixed16_zero(uint_fixed_16_16_t val)
+{
+	if (val.val == 0)
+		return true;
+	return false;
+}
+
+static inline uint_fixed_16_16_t u32_to_fixed16(uint32_t val)
+{
+	uint_fixed_16_16_t fp;
+
+	WARN_ON(val > U16_MAX);
+
+	fp.val = val << 16;
+	return fp;
+}
+
+static inline uint32_t fixed16_to_u32_round_up(uint_fixed_16_16_t fp)
+{
+	return DIV_ROUND_UP(fp.val, 1 << 16);
+}
+
+static inline uint32_t fixed16_to_u32(uint_fixed_16_16_t fp)
+{
+	return fp.val >> 16;
+}
+
+static inline uint_fixed_16_16_t min_fixed16(uint_fixed_16_16_t min1,
+					     uint_fixed_16_16_t min2)
+{
+	uint_fixed_16_16_t min;
+
+	min.val = min(min1.val, min2.val);
+	return min;
+}
+
+static inline uint_fixed_16_16_t max_fixed16(uint_fixed_16_16_t max1,
+					     uint_fixed_16_16_t max2)
+{
+	uint_fixed_16_16_t max;
+
+	max.val = max(max1.val, max2.val);
+	return max;
+}
+
+static inline uint_fixed_16_16_t clamp_u64_to_fixed16(uint64_t val)
+{
+	uint_fixed_16_16_t fp;
+	WARN_ON(val > U32_MAX);
+	fp.val = (uint32_t) val;
+	return fp;
+}
+
+static inline uint32_t div_round_up_fixed16(uint_fixed_16_16_t val,
+					    uint_fixed_16_16_t d)
+{
+	return DIV_ROUND_UP(val.val, d.val);
+}
+
+static inline uint32_t mul_round_up_u32_fixed16(uint32_t val,
+						uint_fixed_16_16_t mul)
+{
+	uint64_t intermediate_val;
+
+	intermediate_val = (uint64_t) val * mul.val;
+	intermediate_val = DIV_ROUND_UP_ULL(intermediate_val, 1 << 16);
+	WARN_ON(intermediate_val > U32_MAX);
+	return (uint32_t) intermediate_val;
+}
+
+static inline uint_fixed_16_16_t mul_fixed16(uint_fixed_16_16_t val,
+					     uint_fixed_16_16_t mul)
+{
+	uint64_t intermediate_val;
+
+	intermediate_val = (uint64_t) val.val * mul.val;
+	intermediate_val = intermediate_val >> 16;
+	return clamp_u64_to_fixed16(intermediate_val);
+}
+
+static inline uint_fixed_16_16_t div_fixed16(uint32_t val, uint32_t d)
+{
+	uint64_t interm_val;
+
+	interm_val = (uint64_t)val << 16;
+	interm_val = DIV_ROUND_UP_ULL(interm_val, d);
+	return clamp_u64_to_fixed16(interm_val);
+}
+
+static inline uint32_t div_round_up_u32_fixed16(uint32_t val,
+						uint_fixed_16_16_t d)
+{
+	uint64_t interm_val;
+
+	interm_val = (uint64_t)val << 16;
+	interm_val = DIV_ROUND_UP_ULL(interm_val, d.val);
+	WARN_ON(interm_val > U32_MAX);
+	return (uint32_t) interm_val;
+}
+
+static inline uint_fixed_16_16_t mul_u32_fixed16(uint32_t val,
+						 uint_fixed_16_16_t mul)
+{
+	uint64_t intermediate_val;
+
+	intermediate_val = (uint64_t) val * mul.val;
+	return clamp_u64_to_fixed16(intermediate_val);
+}
+
+static inline uint_fixed_16_16_t add_fixed16(uint_fixed_16_16_t add1,
+					     uint_fixed_16_16_t add2)
+{
+	uint64_t interm_sum;
+
+	interm_sum = (uint64_t) add1.val + add2.val;
+	return clamp_u64_to_fixed16(interm_sum);
+}
+
+static inline uint_fixed_16_16_t add_fixed16_u32(uint_fixed_16_16_t add1,
+						 uint32_t add2)
+{
+	uint64_t interm_sum;
+	uint_fixed_16_16_t interm_add2 = u32_to_fixed16(add2);
+
+	interm_sum = (uint64_t) add1.val + interm_add2.val;
+	return clamp_u64_to_fixed16(interm_sum);
+}
+
+#endif /* _I915_FIXED_H_ */