1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Support for Intel Camera Imaging ISP subsystem.
4 * Copyright (c) 2015, Intel Corporation.
5 */
6
7 #include "ia_css_types.h"
8 #include "sh_css_defs.h"
9 #include "ia_css_debug.h"
10 #include "assert_support.h"
11
12 #include "ctc/ctc_1.0/ia_css_ctc.host.h"
13 #include "ia_css_ctc1_5.host.h"
14
ctc_gradient(int * dydx,int * shift,int y1,int y0,int x1,int x0)15 static void ctc_gradient(
16 int *dydx, int *shift,
17 int y1, int y0, int x1, int x0)
18 {
19 int frc_bits = max(IA_CSS_CTC_COEF_SHIFT, 16);
20 int dy = y1 - y0;
21 int dx = x1 - x0;
22 int dydx_int;
23 int dydx_frc;
24 int sft;
25 /* max_dydx = the maxinum gradient = the maximum y (gain) */
26 int max_dydx = (1 << IA_CSS_CTC_COEF_SHIFT) - 1;
27
28 if (dx == 0) {
29 ia_css_debug_dtrace(IA_CSS_DEBUG_TRACE_PRIVATE,
30 "ctc_gradient() error, illegal division operation\n");
31 return;
32 } else {
33 dydx_int = dy / dx;
34 dydx_frc = ((dy - dydx_int * dx) << frc_bits) / dx;
35 }
36
37 assert(y0 >= 0 && y0 <= max_dydx);
38 assert(y1 >= 0 && y1 <= max_dydx);
39 assert(x0 < x1);
40 assert(dydx);
41 assert(shift);
42
43 ia_css_debug_dtrace(IA_CSS_DEBUG_TRACE_PRIVATE, "ctc_gradient() enter:\n");
44
45 /* search "sft" which meets this condition:
46 (1 << (IA_CSS_CTC_COEF_SHIFT - 1))
47 <= (((float)dy / (float)dx) * (1 << sft))
48 <= ((1 << IA_CSS_CTC_COEF_SHIFT) - 1) */
49 for (sft = 0; sft <= IA_CSS_CTC_COEF_SHIFT; sft++) {
50 int tmp_dydx = (dydx_int << sft)
51 + (dydx_frc >> (frc_bits - sft));
52 if (tmp_dydx <= max_dydx) {
53 *dydx = tmp_dydx;
54 *shift = sft;
55 }
56 if (tmp_dydx >= max_dydx)
57 break;
58 }
59
60 ia_css_debug_dtrace(IA_CSS_DEBUG_TRACE_PRIVATE, "ctc_gradient() leave:\n");
61 }
62
63 void
ia_css_ctc_encode(struct sh_css_isp_ctc_params * to,const struct ia_css_ctc_config * from,unsigned int size)64 ia_css_ctc_encode(
65 struct sh_css_isp_ctc_params *to,
66 const struct ia_css_ctc_config *from,
67 unsigned int size)
68 {
69 (void)size;
70 to->y0 = from->y0;
71 to->y1 = from->y1;
72 to->y2 = from->y2;
73 to->y3 = from->y3;
74 to->y4 = from->y4;
75 to->y5 = from->y5;
76
77 to->ce_gain_exp = from->ce_gain_exp;
78
79 to->x1 = from->x1;
80 to->x2 = from->x2;
81 to->x3 = from->x3;
82 to->x4 = from->x4;
83
84 ctc_gradient(&to->dydx0,
85 &to->dydx0_shift,
86 from->y1, from->y0,
87 from->x1, 0);
88
89 ctc_gradient(&to->dydx1,
90 &to->dydx1_shift,
91 from->y2, from->y1,
92 from->x2, from->x1);
93
94 ctc_gradient(&to->dydx2,
95 &to->dydx2_shift,
96 from->y3, from->y2,
97 from->x3, from->x2);
98
99 ctc_gradient(&to->dydx3,
100 &to->dydx3_shift,
101 from->y4, from->y3,
102 from->x4, from->x3);
103
104 ctc_gradient(&to->dydx4,
105 &to->dydx4_shift,
106 from->y5, from->y4,
107 SH_CSS_BAYER_MAXVAL, from->x4);
108 }
109
110 void
111 ia_css_ctc_dump(
112 const struct sh_css_isp_ctc_params *ctc,
113 unsigned int level);
114