1/* 2 * Copyright 2012 Haiku, Inc. All rights reserved. 3 * Distributed under the terms of the MIT license. 4 * 5 * Authors: 6 * Gerald Zajac 7 */ 8 9// The code in this file was adapted from the X.org intel driver which had 10// the following copyright and license. 11 12/************************************************************************** 13Copyright 1998-1999 Precision Insight, Inc., Cedar Park, Texas. 14All Rights Reserved. 15 16Permission is hereby granted, free of charge, to any person obtaining a 17copy of this software and associated documentation files (the 18"Software"), to deal in the Software without restriction, including 19without limitation the rights to use, copy, modify, merge, publish, 20distribute, sub license, and/or sell copies of the Software, and to 21permit persons to whom the Software is furnished to do so, subject to 22the following conditions: 23 24The above copyright notice and this permission notice (including the 25next paragraph) shall be included in all copies or substantial portions 26of the Software. 27 28THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS 29OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 30MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. 31IN NO EVENT SHALL PRECISION INSIGHT AND/OR ITS SUPPLIERS BE LIABLE FOR 32ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, 33TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE 34SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. 35**************************************************************************/ 36 37 38#include "accelerant.h" 39 40 41struct WatermarkInfo { 42 double freq; 43 uint32 watermark; 44}; 45 46static WatermarkInfo watermarks_8[] = { 47 { 0, 0x22003000}, 48 {25.2, 0x22003000}, 49 {28.0, 0x22003000}, 50 {31.5, 0x22003000}, 51 {36.0, 0x22007000}, 52 {40.0, 0x22007000}, 53 {45.0, 0x22007000}, 54 {49.5, 0x22008000}, 55 {50.0, 0x22008000}, 56 {56.3, 0x22008000}, 57 {65.0, 0x22008000}, 58 {75.0, 0x22008000}, 59 {78.8, 0x22008000}, 60 {80.0, 0x22008000}, 61 {94.0, 0x22008000}, 62 {96.0, 0x22107000}, 63 {99.0, 0x22107000}, 64 {108.0, 0x22107000}, 65 {121.0, 0x22107000}, 66 {128.9, 0x22107000}, 67 {132.0, 0x22109000}, 68 {135.0, 0x22109000}, 69 {157.5, 0x2210b000}, 70 {162.0, 0x2210b000}, 71 {175.5, 0x2210b000}, 72 {189.0, 0x2220e000}, 73 {202.5, 0x2220e000} 74}; 75 76static WatermarkInfo watermarks_16[] = { 77 { 0, 0x22004000}, 78 {25.2, 0x22006000}, 79 {28.0, 0x22006000}, 80 {31.5, 0x22007000}, 81 {36.0, 0x22007000}, 82 {40.0, 0x22007000}, 83 {45.0, 0x22007000}, 84 {49.5, 0x22009000}, 85 {50.0, 0x22009000}, 86 {56.3, 0x22108000}, 87 {65.0, 0x2210e000}, 88 {75.0, 0x2210e000}, 89 {78.8, 0x2210e000}, 90 {80.0, 0x22210000}, 91 {94.5, 0x22210000}, 92 {96.0, 0x22210000}, 93 {99.0, 0x22210000}, 94 {108.0, 0x22210000}, 95 {121.0, 0x22210000}, 96 {128.9, 0x22210000}, 97 {132.0, 0x22314000}, 98 {135.0, 0x22314000}, 99 {157.5, 0x22415000}, 100 {162.0, 0x22416000}, 101 {175.5, 0x22416000}, 102 {189.0, 0x22416000}, 103 {195.0, 0x22416000}, 104 {202.5, 0x22416000} 105}; 106 107 108uint32 109I810_GetWatermark(const DisplayModeEx& mode) 110{ 111 WatermarkInfo *table; 112 uint32 tableLen; 113 114 // Get burst length and FIFO watermark based upon the bus frequency and 115 // pixel clock. 116 117 switch (mode.bitsPerPixel) { 118 case 8: 119 table = watermarks_8; 120 tableLen = ARRAY_SIZE(watermarks_8); 121 break; 122 case 16: 123 table = watermarks_16; 124 tableLen = ARRAY_SIZE(watermarks_16); 125 break; 126 default: 127 return 0; 128 } 129 130 uint32 i; 131 double clockFreq = mode.timing.pixel_clock / 1000.0; 132 133 for (i = 0; i < tableLen && table[i].freq < clockFreq; i++) 134 ; 135 136 if (i == tableLen) 137 i--; 138 139 TRACE("chosen watermark 0x%lx (freq %f)\n", table[i].watermark, 140 table[i].freq); 141 142 return table[i].watermark; 143} 144