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
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
|
/*
* vrtc.c: Driver for virtual RTC device on Intel MID platform
*
* (C) Copyright 2009 Intel Corporation
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; version 2
* of the License.
*
* Note:
* VRTC is emulated by system controller firmware, the real HW
* RTC is located in the PMIC device. SCU FW shadows PMIC RTC
* in a memory mapped IO space that is visible to the host IA
* processor.
*
* This driver is based on RTC CMOS driver.
*/
#include <linux/kernel.h>
#include <linux/export.h>
#include <linux/init.h>
#include <linux/sfi.h>
#include <linux/platform_device.h>
#include <asm/mrst.h>
#include <asm/mrst-vrtc.h>
#include <asm/time.h>
#include <asm/fixmap.h>
static unsigned char __iomem *vrtc_virt_base;
unsigned char vrtc_cmos_read(unsigned char reg)
{
unsigned char retval;
/* vRTC's registers range from 0x0 to 0xD */
if (reg > 0xd || !vrtc_virt_base)
return 0xff;
lock_cmos_prefix(reg);
retval = __raw_readb(vrtc_virt_base + (reg << 2));
lock_cmos_suffix(reg);
return retval;
}
EXPORT_SYMBOL_GPL(vrtc_cmos_read);
void vrtc_cmos_write(unsigned char val, unsigned char reg)
{
if (reg > 0xd || !vrtc_virt_base)
return;
lock_cmos_prefix(reg);
__raw_writeb(val, vrtc_virt_base + (reg << 2));
lock_cmos_suffix(reg);
}
EXPORT_SYMBOL_GPL(vrtc_cmos_write);
unsigned long vrtc_get_time(void)
{
u8 sec, min, hour, mday, mon;
unsigned long flags;
u32 year;
spin_lock_irqsave(&rtc_lock, flags);
while ((vrtc_cmos_read(RTC_FREQ_SELECT) & RTC_UIP))
cpu_relax();
sec = vrtc_cmos_read(RTC_SECONDS);
min = vrtc_cmos_read(RTC_MINUTES);
hour = vrtc_cmos_read(RTC_HOURS);
mday = vrtc_cmos_read(RTC_DAY_OF_MONTH);
mon = vrtc_cmos_read(RTC_MONTH);
year = vrtc_cmos_read(RTC_YEAR);
spin_unlock_irqrestore(&rtc_lock, flags);
/* vRTC YEAR reg contains the offset to 1972 */
year += 1972;
printk(KERN_INFO "vRTC: sec: %d min: %d hour: %d day: %d "
"mon: %d year: %d\n", sec, min, hour, mday, mon, year);
return mktime(year, mon, mday, hour, min, sec);
}
/* Only care about the minutes and seconds */
int vrtc_set_mmss(unsigned long nowtime)
{
int real_sec, real_min;
unsigned long flags;
int vrtc_min;
spin_lock_irqsave(&rtc_lock, flags);
vrtc_min = vrtc_cmos_read(RTC_MINUTES);
real_sec = nowtime % 60;
real_min = nowtime / 60;
if (((abs(real_min - vrtc_min) + 15)/30) & 1)
real_min += 30;
real_min %= 60;
vrtc_cmos_write(real_sec, RTC_SECONDS);
vrtc_cmos_write(real_min, RTC_MINUTES);
spin_unlock_irqrestore(&rtc_lock, flags);
return 0;
}
void __init mrst_rtc_init(void)
{
unsigned long vrtc_paddr;
sfi_table_parse(SFI_SIG_MRTC, NULL, NULL, sfi_parse_mrtc);
vrtc_paddr = sfi_mrtc_array[0].phys_addr;
if (!sfi_mrtc_num || !vrtc_paddr)
return;
vrtc_virt_base = (void __iomem *)set_fixmap_offset_nocache(FIX_LNW_VRTC,
vrtc_paddr);
x86_platform.get_wallclock = vrtc_get_time;
x86_platform.set_wallclock = vrtc_set_mmss;
}
/*
* The Moorestown platform has a memory mapped virtual RTC device that emulates
* the programming interface of the RTC.
*/
static struct resource vrtc_resources[] = {
[0] = {
.flags = IORESOURCE_MEM,
},
[1] = {
.flags = IORESOURCE_IRQ,
}
};
static struct platform_device vrtc_device = {
.name = "rtc_mrst",
.id = -1,
.resource = vrtc_resources,
.num_resources = ARRAY_SIZE(vrtc_resources),
};
/* Register the RTC device if appropriate */
static int __init mrst_device_create(void)
{
/* No Moorestown, no device */
if (!mrst_identify_cpu())
return -ENODEV;
/* No timer, no device */
if (!sfi_mrtc_num)
return -ENODEV;
/* iomem resource */
vrtc_resources[0].start = sfi_mrtc_array[0].phys_addr;
vrtc_resources[0].end = sfi_mrtc_array[0].phys_addr +
MRST_VRTC_MAP_SZ;
/* irq resource */
vrtc_resources[1].start = sfi_mrtc_array[0].irq;
vrtc_resources[1].end = sfi_mrtc_array[0].irq;
return platform_device_register(&vrtc_device);
}
module_init(mrst_device_create);
|
