Linux Kernel  3.7.1
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timex.h
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1 /*
2  * include/asm-xtensa/timex.h
3  *
4  * This file is subject to the terms and conditions of the GNU General Public
5  * License. See the file "COPYING" in the main directory of this archive
6  * for more details.
7  *
8  * Copyright (C) 2001 - 2005 Tensilica Inc.
9  */
10 
11 #ifndef _XTENSA_TIMEX_H
12 #define _XTENSA_TIMEX_H
13 
14 #ifdef __KERNEL__
15 
16 #include <asm/processor.h>
17 #include <linux/stringify.h>
18 
19 #define _INTLEVEL(x) XCHAL_INT ## x ## _LEVEL
20 #define INTLEVEL(x) _INTLEVEL(x)
21 
22 #if INTLEVEL(XCHAL_TIMER0_INTERRUPT) == 1
23 # define LINUX_TIMER 0
24 # define LINUX_TIMER_INT XCHAL_TIMER0_INTERRUPT
25 #elif INTLEVEL(XCHAL_TIMER1_INTERRUPT) == 1
26 # define LINUX_TIMER 1
27 # define LINUX_TIMER_INT XCHAL_TIMER1_INTERRUPT
28 #elif INTLEVEL(XCHAL_TIMER2_INTERRUPT) == 1
29 # define LINUX_TIMER 2
30 # define LINUX_TIMER_INT XCHAL_TIMER2_INTERRUPT
31 #else
32 # error "Bad timer number for Linux configurations!"
33 #endif
34 
35 #define LINUX_TIMER_MASK (1L << LINUX_TIMER_INT)
36 
37 #define CLOCK_TICK_RATE 1193180 /* (everyone is using this value) */
38 #define CLOCK_TICK_FACTOR 20 /* Factor of both 10^6 and CLOCK_TICK_RATE */
39 
40 #ifdef CONFIG_XTENSA_CALIBRATE_CCOUNT
41 extern unsigned long ccount_per_jiffy;
42 extern unsigned long nsec_per_ccount;
43 #define CCOUNT_PER_JIFFY ccount_per_jiffy
44 #define NSEC_PER_CCOUNT nsec_per_ccount
45 #else
46 #define CCOUNT_PER_JIFFY (CONFIG_XTENSA_CPU_CLOCK*(1000000UL/HZ))
47 #define NSEC_PER_CCOUNT (1000UL / CONFIG_XTENSA_CPU_CLOCK)
48 #endif
49 
50 
51 typedef unsigned long long cycles_t;
52 
53 /*
54  * Only used for SMP.
55  */
56 
57 extern cycles_t cacheflush_time;
58 
59 #define get_cycles() (0)
60 
61 
62 /*
63  * Register access.
64  */
65 
66 #define WSR_CCOUNT(r) asm volatile ("wsr %0, ccount" :: "a" (r))
67 #define RSR_CCOUNT(r) asm volatile ("rsr %0, ccount" : "=a" (r))
68 #define WSR_CCOMPARE(x,r) asm volatile ("wsr %0,"__stringify(SREG_CCOMPARE)"+"__stringify(x) :: "a"(r))
69 #define RSR_CCOMPARE(x,r) asm volatile ("rsr %0,"__stringify(SREG_CCOMPARE)"+"__stringify(x) : "=a"(r))
70 
71 static inline unsigned long get_ccount (void)
72 {
73  unsigned long ccount;
74  RSR_CCOUNT(ccount);
75  return ccount;
76 }
77 
78 static inline void set_ccount (unsigned long ccount)
79 {
80  WSR_CCOUNT(ccount);
81 }
82 
83 static inline unsigned long get_linux_timer (void)
84 {
85  unsigned ccompare;
86  RSR_CCOMPARE(LINUX_TIMER, ccompare);
87  return ccompare;
88 }
89 
90 static inline void set_linux_timer (unsigned long ccompare)
91 {
92  WSR_CCOMPARE(LINUX_TIMER, ccompare);
93 }
94 
95 #endif /* __KERNEL__ */
96 #endif /* _XTENSA_TIMEX_H */