1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Support for Intel Camera Imaging ISP subsystem.
4 * Copyright (c) 2015, Intel Corporation.
5 *
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms and conditions of the GNU General Public License,
8 * version 2, as published by the Free Software Foundation.
9 *
10 * This program is distributed in the hope it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
13 * more details.
14 */
15
16 #include "ia_css_types.h"
17 #include "sh_css_defs.h"
18 #include "assert_support.h"
19
20 #include "ia_css_ctc2.host.h"
21
22 #define INEFFECTIVE_VAL 4096
23 #define BASIC_VAL 819
24
25 /*Default configuration of parameters for Ctc2*/
26 const struct ia_css_ctc2_config default_ctc2_config = {
27 INEFFECTIVE_VAL, INEFFECTIVE_VAL, INEFFECTIVE_VAL,
28 INEFFECTIVE_VAL, INEFFECTIVE_VAL, INEFFECTIVE_VAL,
29 BASIC_VAL * 2, BASIC_VAL * 4, BASIC_VAL * 6,
30 BASIC_VAL * 8, INEFFECTIVE_VAL, INEFFECTIVE_VAL,
31 BASIC_VAL >> 1, BASIC_VAL
32 };
33
34 /* (dydx) = ctc2_slope(y1, y0, x1, x0)
35 * -----------------------------------------------
36 * Calculation of the Slope of a Line = ((y1 - y0) >> 8)/(x1 - x0)
37 *
38 * Note: y1, y0 , x1 & x0 must lie within the range 0 <-> 8191
39 */
ctc2_slope(int y1,int y0,int x1,int x0)40 static int ctc2_slope(int y1, int y0, int x1, int x0)
41 {
42 const int shift_val = 8;
43 const int max_slope = (1 << IA_CSS_CTC_COEF_SHIFT) - 1;
44 int dy = y1 - y0;
45 int dx = x1 - x0;
46 int rounding = (dx + 1) >> 1;
47 int dy_shift = dy << shift_val;
48 int slope, dydx;
49
50 /*Protection for parameter values, & avoiding zero divisions*/
51 assert(y0 >= 0 && y0 <= max_slope);
52 assert(y1 >= 0 && y1 <= max_slope);
53 assert(x0 >= 0 && x0 <= max_slope);
54 assert(x1 > 0 && x1 <= max_slope);
55 assert(dx > 0);
56
57 if (dy < 0)
58 rounding = -rounding;
59 slope = (int)(dy_shift + rounding) / dx;
60
61 /*the slope must lie within the range
62 (-max_slope-1) >= (dydx) >= (max_slope)
63 */
64 if (slope <= -max_slope - 1) {
65 dydx = -max_slope - 1;
66 } else if (slope >= max_slope) {
67 dydx = max_slope;
68 } else {
69 dydx = slope;
70 }
71
72 return dydx;
73 }
74
75 /* (void) = ia_css_ctc2_vmem_encode(*to, *from)
76 * -----------------------------------------------
77 * VMEM Encode Function to translate Y parameters from userspace into ISP space
78 */
ia_css_ctc2_vmem_encode(struct ia_css_isp_ctc2_vmem_params * to,const struct ia_css_ctc2_config * from,size_t size)79 void ia_css_ctc2_vmem_encode(struct ia_css_isp_ctc2_vmem_params *to,
80 const struct ia_css_ctc2_config *from,
81 size_t size)
82 {
83 unsigned int i, j;
84 const unsigned int shffl_blck = 4;
85 const unsigned int length_zeros = 11;
86 short dydx0, dydx1, dydx2, dydx3, dydx4;
87
88 (void)size;
89 /*
90 * Calculation of slopes of lines interconnecting
91 * 0.0 -> y_x1 -> y_x2 -> y _x3 -> y_x4 -> 1.0
92 */
93 dydx0 = ctc2_slope(from->y_y1, from->y_y0,
94 from->y_x1, 0);
95 dydx1 = ctc2_slope(from->y_y2, from->y_y1,
96 from->y_x2, from->y_x1);
97 dydx2 = ctc2_slope(from->y_y3, from->y_y2,
98 from->y_x3, from->y_x2);
99 dydx3 = ctc2_slope(from->y_y4, from->y_y3,
100 from->y_x4, from->y_x3);
101 dydx4 = ctc2_slope(from->y_y5, from->y_y4,
102 SH_CSS_BAYER_MAXVAL, from->y_x4);
103
104 /*Fill 3 arrays with:
105 * - Luma input gain values y_y0, y_y1, y_y2, y_3, y_y4
106 * - Luma kneepoints 0, y_x1, y_x2, y_x3, y_x4
107 * - Calculated slopes dydx0, dyxd1, dydx2, dydx3, dydx4
108 *
109 * - Each 64-element array is divided in blocks of 16 elements:
110 * the 5 parameters + zeros in the remaining 11 positions
111 * - All blocks of the same array will contain the same data
112 */
113 for (i = 0; i < shffl_blck; i++) {
114 to->y_x[0][(i << shffl_blck)] = 0;
115 to->y_x[0][(i << shffl_blck) + 1] = from->y_x1;
116 to->y_x[0][(i << shffl_blck) + 2] = from->y_x2;
117 to->y_x[0][(i << shffl_blck) + 3] = from->y_x3;
118 to->y_x[0][(i << shffl_blck) + 4] = from->y_x4;
119
120 to->y_y[0][(i << shffl_blck)] = from->y_y0;
121 to->y_y[0][(i << shffl_blck) + 1] = from->y_y1;
122 to->y_y[0][(i << shffl_blck) + 2] = from->y_y2;
123 to->y_y[0][(i << shffl_blck) + 3] = from->y_y3;
124 to->y_y[0][(i << shffl_blck) + 4] = from->y_y4;
125
126 to->e_y_slope[0][(i << shffl_blck)] = dydx0;
127 to->e_y_slope[0][(i << shffl_blck) + 1] = dydx1;
128 to->e_y_slope[0][(i << shffl_blck) + 2] = dydx2;
129 to->e_y_slope[0][(i << shffl_blck) + 3] = dydx3;
130 to->e_y_slope[0][(i << shffl_blck) + 4] = dydx4;
131
132 for (j = 0; j < length_zeros; j++) {
133 to->y_x[0][(i << shffl_blck) + 5 + j] = 0;
134 to->y_y[0][(i << shffl_blck) + 5 + j] = 0;
135 to->e_y_slope[0][(i << shffl_blck) + 5 + j] = 0;
136 }
137 }
138 }
139
140 /* (void) = ia_css_ctc2_encode(*to, *from)
141 * -----------------------------------------------
142 * DMEM Encode Function to translate UV parameters from userspace into ISP space
143 */
ia_css_ctc2_encode(struct ia_css_isp_ctc2_dmem_params * to,struct ia_css_ctc2_config * from,size_t size)144 void ia_css_ctc2_encode(struct ia_css_isp_ctc2_dmem_params *to,
145 struct ia_css_ctc2_config *from,
146 size_t size)
147 {
148 (void)size;
149
150 to->uv_y0 = from->uv_y0;
151 to->uv_y1 = from->uv_y1;
152 to->uv_x0 = from->uv_x0;
153 to->uv_x1 = from->uv_x1;
154
155 /*Slope Calculation*/
156 to->uv_dydx = ctc2_slope(from->uv_y1, from->uv_y0,
157 from->uv_x1, from->uv_x0);
158 }
159