diff options
author | Glenn Elliott <gelliott@cs.unc.edu> | 2012-03-04 19:47:13 -0500 |
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committer | Glenn Elliott <gelliott@cs.unc.edu> | 2012-03-04 19:47:13 -0500 |
commit | c71c03bda1e86c9d5198c5d83f712e695c4f2a1e (patch) | |
tree | ecb166cb3e2b7e2adb3b5e292245fefd23381ac8 /arch/x86/platform/mrst/vrtc.c | |
parent | ea53c912f8a86a8567697115b6a0d8152beee5c8 (diff) | |
parent | 6a00f206debf8a5c8899055726ad127dbeeed098 (diff) |
Merge branch 'mpi-master' into wip-k-fmlpwip-k-fmlp
Conflicts:
litmus/sched_cedf.c
Diffstat (limited to 'arch/x86/platform/mrst/vrtc.c')
-rw-r--r-- | arch/x86/platform/mrst/vrtc.c | 159 |
1 files changed, 159 insertions, 0 deletions
diff --git a/arch/x86/platform/mrst/vrtc.c b/arch/x86/platform/mrst/vrtc.c new file mode 100644 index 000000000000..73d70d65e76e --- /dev/null +++ b/arch/x86/platform/mrst/vrtc.c | |||
@@ -0,0 +1,159 @@ | |||
1 | /* | ||
2 | * vrtc.c: Driver for virtual RTC device on Intel MID platform | ||
3 | * | ||
4 | * (C) Copyright 2009 Intel Corporation | ||
5 | * | ||
6 | * This program is free software; you can redistribute it and/or | ||
7 | * modify it under the terms of the GNU General Public License | ||
8 | * as published by the Free Software Foundation; version 2 | ||
9 | * of the License. | ||
10 | * | ||
11 | * Note: | ||
12 | * VRTC is emulated by system controller firmware, the real HW | ||
13 | * RTC is located in the PMIC device. SCU FW shadows PMIC RTC | ||
14 | * in a memory mapped IO space that is visible to the host IA | ||
15 | * processor. | ||
16 | * | ||
17 | * This driver is based on RTC CMOS driver. | ||
18 | */ | ||
19 | |||
20 | #include <linux/kernel.h> | ||
21 | #include <linux/init.h> | ||
22 | #include <linux/sfi.h> | ||
23 | #include <linux/platform_device.h> | ||
24 | |||
25 | #include <asm/mrst.h> | ||
26 | #include <asm/mrst-vrtc.h> | ||
27 | #include <asm/time.h> | ||
28 | #include <asm/fixmap.h> | ||
29 | |||
30 | static unsigned char __iomem *vrtc_virt_base; | ||
31 | |||
32 | unsigned char vrtc_cmos_read(unsigned char reg) | ||
33 | { | ||
34 | unsigned char retval; | ||
35 | |||
36 | /* vRTC's registers range from 0x0 to 0xD */ | ||
37 | if (reg > 0xd || !vrtc_virt_base) | ||
38 | return 0xff; | ||
39 | |||
40 | lock_cmos_prefix(reg); | ||
41 | retval = __raw_readb(vrtc_virt_base + (reg << 2)); | ||
42 | lock_cmos_suffix(reg); | ||
43 | return retval; | ||
44 | } | ||
45 | EXPORT_SYMBOL_GPL(vrtc_cmos_read); | ||
46 | |||
47 | void vrtc_cmos_write(unsigned char val, unsigned char reg) | ||
48 | { | ||
49 | if (reg > 0xd || !vrtc_virt_base) | ||
50 | return; | ||
51 | |||
52 | lock_cmos_prefix(reg); | ||
53 | __raw_writeb(val, vrtc_virt_base + (reg << 2)); | ||
54 | lock_cmos_suffix(reg); | ||
55 | } | ||
56 | EXPORT_SYMBOL_GPL(vrtc_cmos_write); | ||
57 | |||
58 | unsigned long vrtc_get_time(void) | ||
59 | { | ||
60 | u8 sec, min, hour, mday, mon; | ||
61 | u32 year; | ||
62 | |||
63 | while ((vrtc_cmos_read(RTC_FREQ_SELECT) & RTC_UIP)) | ||
64 | cpu_relax(); | ||
65 | |||
66 | sec = vrtc_cmos_read(RTC_SECONDS); | ||
67 | min = vrtc_cmos_read(RTC_MINUTES); | ||
68 | hour = vrtc_cmos_read(RTC_HOURS); | ||
69 | mday = vrtc_cmos_read(RTC_DAY_OF_MONTH); | ||
70 | mon = vrtc_cmos_read(RTC_MONTH); | ||
71 | year = vrtc_cmos_read(RTC_YEAR); | ||
72 | |||
73 | /* vRTC YEAR reg contains the offset to 1960 */ | ||
74 | year += 1960; | ||
75 | |||
76 | printk(KERN_INFO "vRTC: sec: %d min: %d hour: %d day: %d " | ||
77 | "mon: %d year: %d\n", sec, min, hour, mday, mon, year); | ||
78 | |||
79 | return mktime(year, mon, mday, hour, min, sec); | ||
80 | } | ||
81 | |||
82 | /* Only care about the minutes and seconds */ | ||
83 | int vrtc_set_mmss(unsigned long nowtime) | ||
84 | { | ||
85 | int real_sec, real_min; | ||
86 | int vrtc_min; | ||
87 | |||
88 | vrtc_min = vrtc_cmos_read(RTC_MINUTES); | ||
89 | |||
90 | real_sec = nowtime % 60; | ||
91 | real_min = nowtime / 60; | ||
92 | if (((abs(real_min - vrtc_min) + 15)/30) & 1) | ||
93 | real_min += 30; | ||
94 | real_min %= 60; | ||
95 | |||
96 | vrtc_cmos_write(real_sec, RTC_SECONDS); | ||
97 | vrtc_cmos_write(real_min, RTC_MINUTES); | ||
98 | return 0; | ||
99 | } | ||
100 | |||
101 | void __init mrst_rtc_init(void) | ||
102 | { | ||
103 | unsigned long vrtc_paddr; | ||
104 | |||
105 | sfi_table_parse(SFI_SIG_MRTC, NULL, NULL, sfi_parse_mrtc); | ||
106 | |||
107 | vrtc_paddr = sfi_mrtc_array[0].phys_addr; | ||
108 | if (!sfi_mrtc_num || !vrtc_paddr) | ||
109 | return; | ||
110 | |||
111 | vrtc_virt_base = (void __iomem *)set_fixmap_offset_nocache(FIX_LNW_VRTC, | ||
112 | vrtc_paddr); | ||
113 | x86_platform.get_wallclock = vrtc_get_time; | ||
114 | x86_platform.set_wallclock = vrtc_set_mmss; | ||
115 | } | ||
116 | |||
117 | /* | ||
118 | * The Moorestown platform has a memory mapped virtual RTC device that emulates | ||
119 | * the programming interface of the RTC. | ||
120 | */ | ||
121 | |||
122 | static struct resource vrtc_resources[] = { | ||
123 | [0] = { | ||
124 | .flags = IORESOURCE_MEM, | ||
125 | }, | ||
126 | [1] = { | ||
127 | .flags = IORESOURCE_IRQ, | ||
128 | } | ||
129 | }; | ||
130 | |||
131 | static struct platform_device vrtc_device = { | ||
132 | .name = "rtc_mrst", | ||
133 | .id = -1, | ||
134 | .resource = vrtc_resources, | ||
135 | .num_resources = ARRAY_SIZE(vrtc_resources), | ||
136 | }; | ||
137 | |||
138 | /* Register the RTC device if appropriate */ | ||
139 | static int __init mrst_device_create(void) | ||
140 | { | ||
141 | /* No Moorestown, no device */ | ||
142 | if (!mrst_identify_cpu()) | ||
143 | return -ENODEV; | ||
144 | /* No timer, no device */ | ||
145 | if (!sfi_mrtc_num) | ||
146 | return -ENODEV; | ||
147 | |||
148 | /* iomem resource */ | ||
149 | vrtc_resources[0].start = sfi_mrtc_array[0].phys_addr; | ||
150 | vrtc_resources[0].end = sfi_mrtc_array[0].phys_addr + | ||
151 | MRST_VRTC_MAP_SZ; | ||
152 | /* irq resource */ | ||
153 | vrtc_resources[1].start = sfi_mrtc_array[0].irq; | ||
154 | vrtc_resources[1].end = sfi_mrtc_array[0].irq; | ||
155 | |||
156 | return platform_device_register(&vrtc_device); | ||
157 | } | ||
158 | |||
159 | module_init(mrst_device_create); | ||