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
|
/*
* Copyright 2010 Red Hat Inc.
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
* OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
* ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
* OTHER DEALINGS IN THE SOFTWARE.
*
* Authors: Ben Skeggs
*/
#include "pll.h"
#include <subdev/bios.h>
#include <subdev/bios/pll.h>
int
gt215_pll_calc(struct nvkm_subdev *subdev, struct nvbios_pll *info,
u32 freq, int *pN, int *pfN, int *pM, int *P)
{
u32 best_err = ~0, err;
int M, lM, hM, N, fN;
*P = info->vco1.max_freq / freq;
if (*P > info->max_p)
*P = info->max_p;
if (*P < info->min_p)
*P = info->min_p;
lM = (info->refclk + info->vco1.max_inputfreq) / info->vco1.max_inputfreq;
lM = max(lM, (int)info->vco1.min_m);
hM = (info->refclk + info->vco1.min_inputfreq) / info->vco1.min_inputfreq;
hM = min(hM, (int)info->vco1.max_m);
lM = min(lM, hM);
for (M = lM; M <= hM; M++) {
u32 tmp = freq * *P * M;
N = tmp / info->refclk;
fN = tmp % info->refclk;
if (!pfN) {
if (fN >= info->refclk / 2)
N++;
} else {
if (fN < info->refclk / 2)
N--;
fN = tmp - (N * info->refclk);
}
if (N < info->vco1.min_n)
continue;
if (N > info->vco1.max_n)
break;
err = abs(freq - (info->refclk * N / M / *P));
if (err < best_err) {
best_err = err;
*pN = N;
*pM = M;
}
if (pfN) {
*pfN = ((fN << 13) + info->refclk / 2) / info->refclk;
*pfN = (*pfN - 4096) & 0xffff;
return freq;
}
}
if (unlikely(best_err == ~0)) {
nvkm_error(subdev, "unable to find matching pll values\n");
return -EINVAL;
}
return info->refclk * *pN / *pM / *P;
}
|
