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 "ia_css_debug.h"
19 #include "assert_support.h"
20
21 #include "ctc/ctc_1.0/ia_css_ctc.host.h"
22 #include "ia_css_ctc1_5.host.h"
23
ctc_gradient(int * dydx,int * shift,int y1,int y0,int x1,int x0)24 static void ctc_gradient(
25 int *dydx, int *shift,
26 int y1, int y0, int x1, int x0)
27 {
28 int frc_bits = max(IA_CSS_CTC_COEF_SHIFT, 16);
29 int dy = y1 - y0;
30 int dx = x1 - x0;
31 int dydx_int;
32 int dydx_frc;
33 int sft;
34 /* max_dydx = the maxinum gradient = the maximum y (gain) */
35 int max_dydx = (1 << IA_CSS_CTC_COEF_SHIFT) - 1;
36
37 if (dx == 0) {
38 ia_css_debug_dtrace(IA_CSS_DEBUG_TRACE_PRIVATE,
39 "ctc_gradient() error, illegal division operation\n");
40 return;
41 } else {
42 dydx_int = dy / dx;
43 dydx_frc = ((dy - dydx_int * dx) << frc_bits) / dx;
44 }
45
46 assert(y0 >= 0 && y0 <= max_dydx);
47 assert(y1 >= 0 && y1 <= max_dydx);
48 assert(x0 < x1);
49 assert(dydx);
50 assert(shift);
51
52 ia_css_debug_dtrace(IA_CSS_DEBUG_TRACE_PRIVATE, "ctc_gradient() enter:\n");
53
54 /* search "sft" which meets this condition:
55 (1 << (IA_CSS_CTC_COEF_SHIFT - 1))
56 <= (((float)dy / (float)dx) * (1 << sft))
57 <= ((1 << IA_CSS_CTC_COEF_SHIFT) - 1) */
58 for (sft = 0; sft <= IA_CSS_CTC_COEF_SHIFT; sft++) {
59 int tmp_dydx = (dydx_int << sft)
60 + (dydx_frc >> (frc_bits - sft));
61 if (tmp_dydx <= max_dydx) {
62 *dydx = tmp_dydx;
63 *shift = sft;
64 }
65 if (tmp_dydx >= max_dydx)
66 break;
67 }
68
69 ia_css_debug_dtrace(IA_CSS_DEBUG_TRACE_PRIVATE, "ctc_gradient() leave:\n");
70 }
71
72 void
ia_css_ctc_encode(struct sh_css_isp_ctc_params * to,const struct ia_css_ctc_config * from,unsigned int size)73 ia_css_ctc_encode(
74 struct sh_css_isp_ctc_params *to,
75 const struct ia_css_ctc_config *from,
76 unsigned int size)
77 {
78 (void)size;
79 to->y0 = from->y0;
80 to->y1 = from->y1;
81 to->y2 = from->y2;
82 to->y3 = from->y3;
83 to->y4 = from->y4;
84 to->y5 = from->y5;
85
86 to->ce_gain_exp = from->ce_gain_exp;
87
88 to->x1 = from->x1;
89 to->x2 = from->x2;
90 to->x3 = from->x3;
91 to->x4 = from->x4;
92
93 ctc_gradient(&to->dydx0,
94 &to->dydx0_shift,
95 from->y1, from->y0,
96 from->x1, 0);
97
98 ctc_gradient(&to->dydx1,
99 &to->dydx1_shift,
100 from->y2, from->y1,
101 from->x2, from->x1);
102
103 ctc_gradient(&to->dydx2,
104 &to->dydx2_shift,
105 from->y3, from->y2,
106 from->x3, from->x2);
107
108 ctc_gradient(&to->dydx3,
109 &to->dydx3_shift,
110 from->y4, from->y3,
111 from->x4, from->x3);
112
113 ctc_gradient(&to->dydx4,
114 &to->dydx4_shift,
115 from->y5, from->y4,
116 SH_CSS_BAYER_MAXVAL, from->x4);
117 }
118
119 void
120 ia_css_ctc_dump(
121 const struct sh_css_isp_ctc_params *ctc,
122 unsigned int level);
123