mtk-infracfg.c
2.18 KB
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
/*
* Copyright (c) 2015 Pengutronix, Sascha Hauer <kernel@pengutronix.de>
*
* 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/export.h>
#include <linux/jiffies.h>
#include <linux/regmap.h>
#include <linux/soc/mediatek/infracfg.h>
#include <asm/processor.h>
#define INFRA_TOPAXI_PROTECTEN 0x0220
#define INFRA_TOPAXI_PROTECTSTA1 0x0228
/**
* mtk_infracfg_set_bus_protection - enable bus protection
* @regmap: The infracfg regmap
* @mask: The mask containing the protection bits to be enabled.
*
* This function enables the bus protection bits for disabled power
* domains so that the system does not hang when some unit accesses the
* bus while in power down.
*/
int mtk_infracfg_set_bus_protection(struct regmap *infracfg, u32 mask)
{
unsigned long expired;
u32 val;
int ret;
regmap_update_bits(infracfg, INFRA_TOPAXI_PROTECTEN, mask, mask);
expired = jiffies + HZ;
while (1) {
ret = regmap_read(infracfg, INFRA_TOPAXI_PROTECTSTA1, &val);
if (ret)
return ret;
if ((val & mask) == mask)
break;
cpu_relax();
if (time_after(jiffies, expired))
return -EIO;
}
return 0;
}
/**
* mtk_infracfg_clear_bus_protection - disable bus protection
* @regmap: The infracfg regmap
* @mask: The mask containing the protection bits to be disabled.
*
* This function disables the bus protection bits previously enabled with
* mtk_infracfg_set_bus_protection.
*/
int mtk_infracfg_clear_bus_protection(struct regmap *infracfg, u32 mask)
{
unsigned long expired;
int ret;
regmap_update_bits(infracfg, INFRA_TOPAXI_PROTECTEN, mask, 0);
expired = jiffies + HZ;
while (1) {
u32 val;
ret = regmap_read(infracfg, INFRA_TOPAXI_PROTECTSTA1, &val);
if (ret)
return ret;
if (!(val & mask))
break;
cpu_relax();
if (time_after(jiffies, expired))
return -EIO;
}
return 0;
}