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
134
135
136
137
138
139
|
/*
* RTC I/O Bridge interfaces for CSR SiRFprimaII
* ARM access the registers of SYSRTC, GPSRTC and PWRC through this module
*
* Copyright (c) 2011 Cambridge Silicon Radio Limited, a CSR plc group company.
*
* Licensed under GPLv2 or later.
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/io.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_device.h>
#include <linux/of_platform.h>
#define SIRFSOC_CPUIOBRG_CTRL 0x00
#define SIRFSOC_CPUIOBRG_WRBE 0x04
#define SIRFSOC_CPUIOBRG_ADDR 0x08
#define SIRFSOC_CPUIOBRG_DATA 0x0c
/*
* suspend asm codes will access this address to make system deepsleep
* after DRAM becomes self-refresh
*/
void __iomem *sirfsoc_rtciobrg_base;
static DEFINE_SPINLOCK(rtciobrg_lock);
/*
* symbols without lock are only used by suspend asm codes
* and these symbols are not exported too
*/
void sirfsoc_rtc_iobrg_wait_sync(void)
{
while (readl_relaxed(sirfsoc_rtciobrg_base + SIRFSOC_CPUIOBRG_CTRL))
cpu_relax();
}
void sirfsoc_rtc_iobrg_besyncing(void)
{
unsigned long flags;
spin_lock_irqsave(&rtciobrg_lock, flags);
sirfsoc_rtc_iobrg_wait_sync();
spin_unlock_irqrestore(&rtciobrg_lock, flags);
}
EXPORT_SYMBOL_GPL(sirfsoc_rtc_iobrg_besyncing);
u32 __sirfsoc_rtc_iobrg_readl(u32 addr)
{
sirfsoc_rtc_iobrg_wait_sync();
writel_relaxed(0x00, sirfsoc_rtciobrg_base + SIRFSOC_CPUIOBRG_WRBE);
writel_relaxed(addr, sirfsoc_rtciobrg_base + SIRFSOC_CPUIOBRG_ADDR);
writel_relaxed(0x01, sirfsoc_rtciobrg_base + SIRFSOC_CPUIOBRG_CTRL);
sirfsoc_rtc_iobrg_wait_sync();
return readl_relaxed(sirfsoc_rtciobrg_base + SIRFSOC_CPUIOBRG_DATA);
}
u32 sirfsoc_rtc_iobrg_readl(u32 addr)
{
unsigned long flags, val;
spin_lock_irqsave(&rtciobrg_lock, flags);
val = __sirfsoc_rtc_iobrg_readl(addr);
spin_unlock_irqrestore(&rtciobrg_lock, flags);
return val;
}
EXPORT_SYMBOL_GPL(sirfsoc_rtc_iobrg_readl);
void sirfsoc_rtc_iobrg_pre_writel(u32 val, u32 addr)
{
sirfsoc_rtc_iobrg_wait_sync();
writel_relaxed(0xf1, sirfsoc_rtciobrg_base + SIRFSOC_CPUIOBRG_WRBE);
writel_relaxed(addr, sirfsoc_rtciobrg_base + SIRFSOC_CPUIOBRG_ADDR);
writel_relaxed(val, sirfsoc_rtciobrg_base + SIRFSOC_CPUIOBRG_DATA);
}
void sirfsoc_rtc_iobrg_writel(u32 val, u32 addr)
{
unsigned long flags;
spin_lock_irqsave(&rtciobrg_lock, flags);
sirfsoc_rtc_iobrg_pre_writel(val, addr);
writel_relaxed(0x01, sirfsoc_rtciobrg_base + SIRFSOC_CPUIOBRG_CTRL);
sirfsoc_rtc_iobrg_wait_sync();
spin_unlock_irqrestore(&rtciobrg_lock, flags);
}
EXPORT_SYMBOL_GPL(sirfsoc_rtc_iobrg_writel);
static const struct of_device_id rtciobrg_ids[] = {
{ .compatible = "sirf,prima2-rtciobg" },
{}
};
static int sirfsoc_rtciobrg_probe(struct platform_device *op)
{
struct device_node *np = op->dev.of_node;
sirfsoc_rtciobrg_base = of_iomap(np, 0);
if (!sirfsoc_rtciobrg_base)
panic("unable to map rtc iobrg registers\n");
return 0;
}
static struct platform_driver sirfsoc_rtciobrg_driver = {
.probe = sirfsoc_rtciobrg_probe,
.driver = {
.name = "sirfsoc-rtciobrg",
.owner = THIS_MODULE,
.of_match_table = rtciobrg_ids,
},
};
static int __init sirfsoc_rtciobrg_init(void)
{
return platform_driver_register(&sirfsoc_rtciobrg_driver);
}
postcore_initcall(sirfsoc_rtciobrg_init);
MODULE_AUTHOR("Zhiwu Song <zhiwu.song@csr.com>, "
"Barry Song <baohua.song@csr.com>");
MODULE_DESCRIPTION("CSR SiRFprimaII rtc io bridge");
MODULE_LICENSE("GPL");
|
