1 /*
2  * linux/drivers/video/omap2/dss/dispc_coefs.c
3  *
4  * Copyright (C) 2011 Texas Instruments
5  * Author: Chandrabhanu Mahapatra <cmahapatra@ti.com>
6  *
7  * This program is free software; you can redistribute it and/or modify it
8  * under the terms of the GNU General Public License version 2 as published by
9  * the Free Software Foundation.
10  *
11  * This program is distributed in the hope that it will be useful, but WITHOUT
12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
14  * more details.
15  *
16  * You should have received a copy of the GNU General Public License along with
17  * this program.  If not, see <http://www.gnu.org/licenses/>.
18  */
19 
20 #include <linux/kernel.h>
21 #include <video/omapfb_dss.h>
22 
23 #include "dispc.h"
24 
25 static const struct dispc_coef coef3_M8[8] = {
26 	{ 0,  0, 128,  0, 0 },
27 	{ 0, -4, 123,  9, 0 },
28 	{ 0, -4, 108, 24, 0 },
29 	{ 0, -2,  87, 43, 0 },
30 	{ 0, 64,  64,  0, 0 },
31 	{ 0, 43,  87, -2, 0 },
32 	{ 0, 24, 108, -4, 0 },
33 	{ 0,  9, 123, -4, 0 },
34 };
35 
36 static const struct dispc_coef coef3_M9[8] = {
37 	{ 0,  6, 116,  6, 0 },
38 	{ 0,  0, 112, 16, 0 },
39 	{ 0, -2, 100, 30, 0 },
40 	{ 0, -2,  83, 47, 0 },
41 	{ 0, 64,  64,  0, 0 },
42 	{ 0, 47,  83, -2, 0 },
43 	{ 0, 30, 100, -2, 0 },
44 	{ 0, 16, 112,  0, 0 },
45 };
46 
47 static const struct dispc_coef coef3_M10[8] = {
48 	{ 0, 10, 108, 10, 0 },
49 	{ 0,  3, 104, 21, 0 },
50 	{ 0,  0,  94, 34, 0 },
51 	{ 0, -1,  80, 49, 0 },
52 	{ 0, 64,  64,  0, 0 },
53 	{ 0, 49,  80, -1, 0 },
54 	{ 0, 34,  94,  0, 0 },
55 	{ 0, 21, 104,  3, 0 },
56 };
57 
58 static const struct dispc_coef coef3_M11[8] = {
59 	{ 0, 14, 100, 14, 0 },
60 	{ 0,  6,  98, 24, 0 },
61 	{ 0,  2,  90, 36, 0 },
62 	{ 0,  0,  78, 50, 0 },
63 	{ 0, 64,  64,  0, 0 },
64 	{ 0, 50,  78,  0, 0 },
65 	{ 0, 36,  90,  2, 0 },
66 	{ 0, 24,  98,  6, 0 },
67 };
68 
69 static const struct dispc_coef coef3_M12[8] = {
70 	{ 0, 16,  96, 16, 0 },
71 	{ 0,  9,  93, 26, 0 },
72 	{ 0,  4,  86, 38, 0 },
73 	{ 0,  1,  76, 51, 0 },
74 	{ 0, 64,  64,  0, 0 },
75 	{ 0, 51,  76,  1, 0 },
76 	{ 0, 38,  86,  4, 0 },
77 	{ 0, 26,  93,  9, 0 },
78 };
79 
80 static const struct dispc_coef coef3_M13[8] = {
81 	{ 0, 18,  92, 18, 0 },
82 	{ 0, 10,  90, 28, 0 },
83 	{ 0,  5,  83, 40, 0 },
84 	{ 0,  1,  75, 52, 0 },
85 	{ 0, 64,  64,  0, 0 },
86 	{ 0, 52,  75,  1, 0 },
87 	{ 0, 40,  83,  5, 0 },
88 	{ 0, 28,  90, 10, 0 },
89 };
90 
91 static const struct dispc_coef coef3_M14[8] = {
92 	{ 0, 20, 88, 20, 0 },
93 	{ 0, 12, 86, 30, 0 },
94 	{ 0,  6, 81, 41, 0 },
95 	{ 0,  2, 74, 52, 0 },
96 	{ 0, 64, 64,  0, 0 },
97 	{ 0, 52, 74,  2, 0 },
98 	{ 0, 41, 81,  6, 0 },
99 	{ 0, 30, 86, 12, 0 },
100 };
101 
102 static const struct dispc_coef coef3_M16[8] = {
103 	{ 0, 22, 84, 22, 0 },
104 	{ 0, 14, 82, 32, 0 },
105 	{ 0,  8, 78, 42, 0 },
106 	{ 0,  3, 72, 53, 0 },
107 	{ 0, 64, 64,  0, 0 },
108 	{ 0, 53, 72,  3, 0 },
109 	{ 0, 42, 78,  8, 0 },
110 	{ 0, 32, 82, 14, 0 },
111 };
112 
113 static const struct dispc_coef coef3_M19[8] = {
114 	{ 0, 24, 80, 24, 0 },
115 	{ 0, 16, 79, 33, 0 },
116 	{ 0,  9, 76, 43, 0 },
117 	{ 0,  4, 70, 54, 0 },
118 	{ 0, 64, 64,  0, 0 },
119 	{ 0, 54, 70,  4, 0 },
120 	{ 0, 43, 76,  9, 0 },
121 	{ 0, 33, 79, 16, 0 },
122 };
123 
124 static const struct dispc_coef coef3_M22[8] = {
125 	{ 0, 25, 78, 25, 0 },
126 	{ 0, 17, 77, 34, 0 },
127 	{ 0, 10, 74, 44, 0 },
128 	{ 0,  5, 69, 54, 0 },
129 	{ 0, 64, 64,  0, 0 },
130 	{ 0, 54, 69,  5, 0 },
131 	{ 0, 44, 74, 10, 0 },
132 	{ 0, 34, 77, 17, 0 },
133 };
134 
135 static const struct dispc_coef coef3_M26[8] = {
136 	{ 0, 26, 76, 26, 0 },
137 	{ 0, 19, 74, 35, 0 },
138 	{ 0, 11, 72, 45, 0 },
139 	{ 0,  5, 69, 54, 0 },
140 	{ 0, 64, 64,  0, 0 },
141 	{ 0, 54, 69,  5, 0 },
142 	{ 0, 45, 72, 11, 0 },
143 	{ 0, 35, 74, 19, 0 },
144 };
145 
146 static const struct dispc_coef coef3_M32[8] = {
147 	{ 0, 27, 74, 27, 0 },
148 	{ 0, 19, 73, 36, 0 },
149 	{ 0, 12, 71, 45, 0 },
150 	{ 0,  6, 68, 54, 0 },
151 	{ 0, 64, 64,  0, 0 },
152 	{ 0, 54, 68,  6, 0 },
153 	{ 0, 45, 71, 12, 0 },
154 	{ 0, 36, 73, 19, 0 },
155 };
156 
157 static const struct dispc_coef coef5_M8[8] = {
158 	{   0,   0, 128,   0,   0 },
159 	{  -2,  14, 125, -10,   1 },
160 	{  -6,  33, 114, -15,   2 },
161 	{ -10,  55,  98, -16,   1 },
162 	{   0, -14,  78,  78, -14 },
163 	{   1, -16,  98,  55, -10 },
164 	{   2, -15, 114,  33,  -6 },
165 	{   1, -10, 125,  14,  -2 },
166 };
167 
168 static const struct dispc_coef coef5_M9[8] = {
169 	{  -3,  10, 114,  10,  -3 },
170 	{  -6,  24, 111,   0,  -1 },
171 	{  -8,  40, 103,  -7,   0 },
172 	{ -11,  58,  91, -11,   1 },
173 	{   0, -12,  76,  76, -12 },
174 	{   1, -11,  91,  58, -11 },
175 	{   0,  -7, 103,  40,  -8 },
176 	{  -1,   0, 111,  24,  -6 },
177 };
178 
179 static const struct dispc_coef coef5_M10[8] = {
180 	{  -4,  18, 100,  18,  -4 },
181 	{  -6,  30,  99,   8,  -3 },
182 	{  -8,  44,  93,   0,  -1 },
183 	{  -9,  58,  84,  -5,   0 },
184 	{   0,  -8,  72,  72,  -8 },
185 	{   0,  -5,  84,  58,  -9 },
186 	{  -1,   0,  93,  44,  -8 },
187 	{  -3,   8,  99,  30,  -6 },
188 };
189 
190 static const struct dispc_coef coef5_M11[8] = {
191 	{  -5,  23,  92,  23,  -5 },
192 	{  -6,  34,  90,  13,  -3 },
193 	{  -6,  45,  85,   6,  -2 },
194 	{  -6,  57,  78,   0,  -1 },
195 	{   0,  -4,  68,  68,  -4 },
196 	{  -1,   0,  78,  57,  -6 },
197 	{  -2,   6,  85,  45,  -6 },
198 	{  -3,  13,  90,  34,  -6 },
199 };
200 
201 static const struct dispc_coef coef5_M12[8] = {
202 	{  -4,  26,  84,  26,  -4 },
203 	{  -5,  36,  82,  18,  -3 },
204 	{  -4,  46,  78,  10,  -2 },
205 	{  -3,  55,  72,   5,  -1 },
206 	{   0,   0,  64,  64,   0 },
207 	{  -1,   5,  72,  55,  -3 },
208 	{  -2,  10,  78,  46,  -4 },
209 	{  -3,  18,  82,  36,  -5 },
210 };
211 
212 static const struct dispc_coef coef5_M13[8] = {
213 	{  -3,  28,  78,  28,  -3 },
214 	{  -3,  37,  76,  21,  -3 },
215 	{  -2,  45,  73,  14,  -2 },
216 	{   0,  53,  68,   8,  -1 },
217 	{   0,   3,  61,  61,   3 },
218 	{  -1,   8,  68,  53,   0 },
219 	{  -2,  14,  73,  45,  -2 },
220 	{  -3,  21,  76,  37,  -3 },
221 };
222 
223 static const struct dispc_coef coef5_M14[8] = {
224 	{  -2,  30,  72,  30,  -2 },
225 	{  -1,  37,  71,  23,  -2 },
226 	{   0,  45,  69,  16,  -2 },
227 	{   3,  52,  64,  10,  -1 },
228 	{   0,   6,  58,  58,   6 },
229 	{  -1,  10,  64,  52,   3 },
230 	{  -2,  16,  69,  45,   0 },
231 	{  -2,  23,  71,  37,  -1 },
232 };
233 
234 static const struct dispc_coef coef5_M16[8] = {
235 	{   0,  31,  66,  31,   0 },
236 	{   1,  38,  65,  25,  -1 },
237 	{   3,  44,  62,  20,  -1 },
238 	{   6,  49,  59,  14,   0 },
239 	{   0,  10,  54,  54,  10 },
240 	{   0,  14,  59,  49,   6 },
241 	{  -1,  20,  62,  44,   3 },
242 	{  -1,  25,  65,  38,   1 },
243 };
244 
245 static const struct dispc_coef coef5_M19[8] = {
246 	{   3,  32,  58,  32,   3 },
247 	{   4,  38,  58,  27,   1 },
248 	{   7,  42,  55,  23,   1 },
249 	{  10,  46,  54,  18,   0 },
250 	{   0,  14,  50,  50,  14 },
251 	{   0,  18,  54,  46,  10 },
252 	{   1,  23,  55,  42,   7 },
253 	{   1,  27,  58,  38,   4 },
254 };
255 
256 static const struct dispc_coef coef5_M22[8] = {
257 	{   4,  33,  54,  33,   4 },
258 	{   6,  37,  54,  28,   3 },
259 	{   9,  41,  53,  24,   1 },
260 	{  12,  45,  51,  20,   0 },
261 	{   0,  16,  48,  48,  16 },
262 	{   0,  20,  51,  45,  12 },
263 	{   1,  24,  53,  41,   9 },
264 	{   3,  28,  54,  37,   6 },
265 };
266 
267 static const struct dispc_coef coef5_M26[8] = {
268 	{   6,  33,  50,  33,   6 },
269 	{   8,  36,  51,  29,   4 },
270 	{  11,  40,  50,  25,   2 },
271 	{  14,  43,  48,  22,   1 },
272 	{   0,  18,  46,  46,  18 },
273 	{   1,  22,  48,  43,  14 },
274 	{   2,  25,  50,  40,  11 },
275 	{   4,  29,  51,  36,   8 },
276 };
277 
278 static const struct dispc_coef coef5_M32[8] = {
279 	{   7,  33,  48,  33,   7 },
280 	{  10,  36,  48,  29,   5 },
281 	{  13,  39,  47,  26,   3 },
282 	{  16,  42,  46,  23,   1 },
283 	{   0,  19,  45,  45,  19 },
284 	{   1,  23,  46,  42,  16 },
285 	{   3,  26,  47,  39,  13 },
286 	{   5,  29,  48,  36,  10 },
287 };
288 
289 const struct dispc_coef *dispc_ovl_get_scale_coef(int inc, int five_taps)
290 {
291 	int i;
292 	static const struct {
293 		int Mmin;
294 		int Mmax;
295 		const struct dispc_coef *coef_3;
296 		const struct dispc_coef *coef_5;
297 	} coefs[] = {
298 		{ 27, 32, coef3_M32, coef5_M32 },
299 		{ 23, 26, coef3_M26, coef5_M26 },
300 		{ 20, 22, coef3_M22, coef5_M22 },
301 		{ 17, 19, coef3_M19, coef5_M19 },
302 		{ 15, 16, coef3_M16, coef5_M16 },
303 		{ 14, 14, coef3_M14, coef5_M14 },
304 		{ 13, 13, coef3_M13, coef5_M13 },
305 		{ 12, 12, coef3_M12, coef5_M12 },
306 		{ 11, 11, coef3_M11, coef5_M11 },
307 		{ 10, 10, coef3_M10, coef5_M10 },
308 		{  9,  9,  coef3_M9,  coef5_M9 },
309 		{  4,  8,  coef3_M8,  coef5_M8 },
310 		/*
311 		 * When upscaling more than two times, blockiness and outlines
312 		 * around the image are observed when M8 tables are used. M11,
313 		 * M16 and M19 tables are used to prevent this.
314 		 */
315 		{  3,  3, coef3_M11, coef5_M11 },
316 		{  2,  2, coef3_M16, coef5_M16 },
317 		{  0,  1, coef3_M19, coef5_M19 },
318 	};
319 
320 	inc /= 128;
321 	for (i = 0; i < ARRAY_SIZE(coefs); ++i)
322 		if (inc >= coefs[i].Mmin && inc <= coefs[i].Mmax)
323 			return five_taps ? coefs[i].coef_5 : coefs[i].coef_3;
324 	return NULL;
325 }
326