diff options
Diffstat (limited to 'include')
-rw-r--r-- | include/drm/drm_fixed.h | 67 |
1 files changed, 67 insertions, 0 deletions
diff --git a/include/drm/drm_fixed.h b/include/drm/drm_fixed.h new file mode 100644 index 00000000000..4a08a664ff1 --- /dev/null +++ b/include/drm/drm_fixed.h @@ -0,0 +1,67 @@ +/* + * Copyright 2009 Red Hat Inc. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR + * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, + * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR + * OTHER DEALINGS IN THE SOFTWARE. + * + * Authors: Dave Airlie + */ +#ifndef DRM_FIXED_H +#define DRM_FIXED_H + +typedef union dfixed { + u32 full; +} fixed20_12; + + +#define dfixed_const(A) (u32)(((A) << 12))/* + ((B + 0.000122)*4096)) */ +#define dfixed_const_half(A) (u32)(((A) << 12) + 2048) +#define dfixed_const_666(A) (u32)(((A) << 12) + 2731) +#define dfixed_const_8(A) (u32)(((A) << 12) + 3277) +#define dfixed_mul(A, B) ((u64)((u64)(A).full * (B).full + 2048) >> 12) +#define dfixed_init(A) { .full = dfixed_const((A)) } +#define dfixed_init_half(A) { .full = dfixed_const_half((A)) } +#define dfixed_trunc(A) ((A).full >> 12) + +static inline u32 dfixed_floor(fixed20_12 A) +{ + u32 non_frac = dfixed_trunc(A); + + return dfixed_const(non_frac); +} + +static inline u32 dfixed_ceil(fixed20_12 A) +{ + u32 non_frac = dfixed_trunc(A); + + if (A.full > dfixed_const(non_frac)) + return dfixed_const(non_frac + 1); + else + return dfixed_const(non_frac); +} + +static inline u32 dfixed_div(fixed20_12 A, fixed20_12 B) +{ + u64 tmp = ((u64)A.full << 13); + + do_div(tmp, B.full); + tmp += 1; + tmp /= 2; + return lower_32_bits(tmp); +} +#endif |