1 /* 2 * Copyright 2009 Red Hat Inc. 3 * 4 * Permission is hereby granted, free of charge, to any person obtaining a 5 * copy of this software and associated documentation files (the "Software"), 6 * to deal in the Software without restriction, including without limitation 7 * the rights to use, copy, modify, merge, publish, distribute, sublicense, 8 * and/or sell copies of the Software, and to permit persons to whom the 9 * Software is furnished to do so, subject to the following conditions: 10 * 11 * The above copyright notice and this permission notice shall be included in 12 * all copies or substantial portions of the Software. 13 * 14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 15 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 17 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR 18 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, 19 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR 20 * OTHER DEALINGS IN THE SOFTWARE. 21 * 22 * Authors: Dave Airlie 23 */ 24 25 #include <sys/cdefs.h> 26 #ifndef DRM_FIXED_H 27 #define DRM_FIXED_H 28 29 typedef union dfixed { 30 u32 full; 31 } fixed20_12; 32 33 34 #define dfixed_const(A) (u32)(((A) << 12))/* + ((B + 0.000122)*4096)) */ 35 #define dfixed_const_half(A) (u32)(((A) << 12) + 2048) 36 #define dfixed_const_666(A) (u32)(((A) << 12) + 2731) 37 #define dfixed_const_8(A) (u32)(((A) << 12) + 3277) 38 #define dfixed_mul(A, B) ((u64)((u64)(A).full * (B).full + 2048) >> 12) 39 #define dfixed_init(A) { .full = dfixed_const((A)) } 40 #define dfixed_init_half(A) { .full = dfixed_const_half((A)) } 41 #define dfixed_trunc(A) ((A).full >> 12) 42 #define dfixed_frac(A) ((A).full & ((1 << 12) - 1)) 43 44 static inline u32 dfixed_floor(fixed20_12 A) 45 { 46 u32 non_frac = dfixed_trunc(A); 47 48 return dfixed_const(non_frac); 49 } 50 51 static inline u32 dfixed_ceil(fixed20_12 A) 52 { 53 u32 non_frac = dfixed_trunc(A); 54 55 if (A.full > dfixed_const(non_frac)) 56 return dfixed_const(non_frac + 1); 57 else 58 return dfixed_const(non_frac); 59 } 60 61 static inline u32 dfixed_div(fixed20_12 A, fixed20_12 B) 62 { 63 u64 tmp = ((u64)A.full << 13); 64 65 do_div(tmp, B.full); 66 tmp += 1; 67 tmp /= 2; 68 return lower_32_bits(tmp); 69 } 70 #endif 71