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