5113f6f70
 김현기
kernel add
|
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
|
/*
* Utility functions for parsing Tegra CVB voltage tables
*
* Copyright (C) 2012-2014 NVIDIA Corporation. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
*/
#include <linux/err.h>
#include <linux/kernel.h>
#include <linux/pm_opp.h>
#include "cvb.h"
/* cvb_mv = ((c2 * speedo / s_scale + c1) * speedo / s_scale + c0) */
static inline int get_cvb_voltage(int speedo, int s_scale,
const struct cvb_coefficients *cvb)
{
int mv;
/* apply only speedo scale: output mv = cvb_mv * v_scale */
mv = DIV_ROUND_CLOSEST(cvb->c2 * speedo, s_scale);
mv = DIV_ROUND_CLOSEST((mv + cvb->c1) * speedo, s_scale) + cvb->c0;
return mv;
}
static int round_cvb_voltage(int mv, int v_scale,
const struct rail_alignment *align)
{
/* combined: apply voltage scale and round to cvb alignment step */
int uv;
int step = (align->step_uv ? : 1000) * v_scale;
int offset = align->offset_uv * v_scale;
uv = max(mv * 1000, offset) - offset;
uv = DIV_ROUND_UP(uv, step) * align->step_uv + align->offset_uv;
return uv / 1000;
}
enum {
DOWN,
UP
};
static int round_voltage(int mv, const struct rail_alignment *align, int up)
{
if (align->step_uv) {
int uv;
uv = max(mv * 1000, align->offset_uv) - align->offset_uv;
uv = (uv + (up ? align->step_uv - 1 : 0)) / align->step_uv;
return (uv * align->step_uv + align->offset_uv) / 1000;
}
return mv;
}
static int build_opp_table(const struct cvb_table *d,
int speedo_value,
unsigned long max_freq,
struct device *opp_dev)
{
int i, ret, dfll_mv, min_mv, max_mv;
const struct cvb_table_freq_entry *table = NULL;
const struct rail_alignment *align = &d->alignment;
min_mv = round_voltage(d->min_millivolts, align, UP);
max_mv = round_voltage(d->max_millivolts, align, DOWN);
for (i = 0; i < MAX_DVFS_FREQS; i++) {
table = &d->cvb_table[i];
if (!table->freq || (table->freq > max_freq))
break;
dfll_mv = get_cvb_voltage(
speedo_value, d->speedo_scale, &table->coefficients);
dfll_mv = round_cvb_voltage(dfll_mv, d->voltage_scale, align);
dfll_mv = clamp(dfll_mv, min_mv, max_mv);
ret = dev_pm_opp_add(opp_dev, table->freq, dfll_mv * 1000);
if (ret)
return ret;
}
return 0;
}
/**
* tegra_cvb_build_opp_table - build OPP table from Tegra CVB tables
* @cvb_tables: array of CVB tables
* @sz: size of the previously mentioned array
* @process_id: process id of the HW module
* @speedo_id: speedo id of the HW module
* @speedo_value: speedo value of the HW module
* @max_rate: highest safe clock rate
* @opp_dev: the struct device * for which the OPP table is built
*
* On Tegra, a CVB table encodes the relationship between operating voltage
* and safe maximal frequency for a given module (e.g. GPU or CPU). This
* function calculates the optimal voltage-frequency operating points
* for the given arguments and exports them via the OPP library for the
* given @opp_dev. Returns a pointer to the struct cvb_table that matched
* or an ERR_PTR on failure.
*/
const struct cvb_table *tegra_cvb_build_opp_table(
const struct cvb_table *cvb_tables,
size_t sz, int process_id,
int speedo_id, int speedo_value,
unsigned long max_rate,
struct device *opp_dev)
{
int i, ret;
for (i = 0; i < sz; i++) {
const struct cvb_table *d = &cvb_tables[i];
if (d->speedo_id != -1 && d->speedo_id != speedo_id)
continue;
if (d->process_id != -1 && d->process_id != process_id)
continue;
ret = build_opp_table(d, speedo_value, max_rate, opp_dev);
return ret ? ERR_PTR(ret) : d;
}
return ERR_PTR(-EINVAL);
}
|