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MN10300: Generic time support
[linux-3.10.git] / arch / mn10300 / unit-asb2364 / include / unit / timex.h
1 /* timex.h: MN2WS0038 architecture timer specifications
2  *
3  * Copyright (C) 2002, 2010 Red Hat, Inc. All Rights Reserved.
4  * Written by David Howells (dhowells@redhat.com)
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; either version
9  * 2 of the License, or (at your option) any later version.
10  */
11 #ifndef _ASM_UNIT_TIMEX_H
12 #define _ASM_UNIT_TIMEX_H
13
14 #ifndef __ASSEMBLY__
15 #include <linux/irq.h>
16 #endif /* __ASSEMBLY__ */
17
18 #include <asm/timer-regs.h>
19 #include <unit/clock.h>
20 #include <asm/param.h>
21
22 /*
23  * jiffies counter specifications
24  */
25
26 #define TMJCBR_MAX              0xffffff        /* 24bit */
27 #define TMJCIRQ                 TMTIRQ
28
29 #ifndef __ASSEMBLY__
30
31 #define MN10300_SRC_IOBCLK      MN10300_IOBCLK
32
33 #ifndef HZ
34 # error HZ undeclared.
35 #endif /* !HZ */
36
37 #define MN10300_JCCLK           (MN10300_SRC_IOBCLK)
38 #define MN10300_TSCCLK          (MN10300_SRC_IOBCLK)
39
40 #define MN10300_JC_PER_HZ       ((MN10300_JCCLK + HZ / 2) / HZ)
41 #define MN10300_TSC_PER_HZ      ((MN10300_TSCCLK + HZ / 2) / HZ)
42
43 /* Check bit width of MTM interval value that sets base register */
44 #if (MN10300_JC_PER_HZ - 1) > TMJCBR_MAX
45 # error MTM tick timer interval value is overflow.
46 #endif
47
48 static inline void stop_jiffies_counter(void)
49 {
50         u16 tmp;
51         TMTMD = 0;
52         tmp = TMTMD;
53 }
54
55 static inline void reload_jiffies_counter(u32 cnt)
56 {
57         u32 tmp;
58
59         TMTBR = cnt;
60         tmp = TMTBR;
61
62         TMTMD = TMTMD_TMTLDE;
63         TMTMD = TMTMD_TMTCNE;
64         tmp = TMTMD;
65 }
66
67 #if defined(CONFIG_SMP) && defined(CONFIG_GENERIC_CLOCKEVENTS) && \
68     !defined(CONFIG_GENERIC_CLOCKEVENTS_BROADCAST)
69 /*
70  * If we aren't using broadcasting, each core needs its own event timer.
71  * Since CPU0 uses the tick timer which is 24-bits, we use timer 4 & 5
72  * cascaded to 32-bits for CPU1 (but only really use 24-bits to match
73  * CPU0).
74  */
75
76 #define TMJC1IRQ                TM5IRQ
77
78 static inline void stop_jiffies_counter1(void)
79 {
80         u8 tmp;
81         TM4MD = 0;
82         TM5MD = 0;
83         tmp = TM4MD;
84         tmp = TM5MD;
85 }
86
87 static inline void reload_jiffies_counter1(u32 cnt)
88 {
89         u32 tmp;
90
91         TM45BR = cnt;
92         tmp = TM45BR;
93
94         TM4MD = TM4MD_INIT_COUNTER;
95         tmp = TM4MD;
96
97         TM5MD = TM5MD_SRC_TM4CASCADE | TM5MD_INIT_COUNTER;
98         TM5MD = TM5MD_SRC_TM4CASCADE | TM5MD_COUNT_ENABLE;
99         tmp = TM5MD;
100
101         TM4MD = TM4MD_COUNT_ENABLE;
102         tmp = TM4MD;
103 }
104 #endif /* CONFIG_SMP&GENERIC_CLOCKEVENTS&!GENERIC_CLOCKEVENTS_BROADCAST */
105
106 #endif /* !__ASSEMBLY__ */
107
108
109 /*
110  * timestamp counter specifications
111  */
112 #define TMTSCBR_MAX     0xffffffff
113
114 #ifndef __ASSEMBLY__
115
116 /* Use 32-bit timestamp counter */
117 #define TMTSCMD         TMSMD
118 #define TMTSCBR         TMSBR
119 #define TMTSCBC         TMSBC
120 #define TMTSCICR        TMSICR
121
122 static inline void startup_timestamp_counter(void)
123 {
124         u32 sync;
125
126         /* set up TMS(Timestamp) 32bit timer register to count real time
127          * - count down from 4Gig-1 to 0 and wrap at IOBCLK rate
128          */
129
130         TMTSCBR = TMTSCBR_MAX;
131         sync = TMTSCBR;
132
133         TMTSCICR = 0;
134         sync = TMTSCICR;
135
136         TMTSCMD = TMTMD_TMTLDE;
137         TMTSCMD = TMTMD_TMTCNE;
138         sync = TMTSCMD;
139 }
140
141 static inline void shutdown_timestamp_counter(void)
142 {
143         TMTSCMD = 0;
144 }
145
146 /*
147  * we use a cascaded pair of 16-bit down-counting timers to count I/O
148  * clock cycles for the purposes of time keeping
149  */
150 typedef unsigned long cycles_t;
151
152 static inline cycles_t read_timestamp_counter(void)
153 {
154         return (cycles_t)~TMTSCBC;
155 }
156
157 #endif /* !__ASSEMBLY__ */
158
159 #endif /* _ASM_UNIT_TIMEX_H */