xref: /openbmc/linux/arch/powerpc/include/asm/timex.h (revision 84d517f3)
1 #ifndef _ASM_POWERPC_TIMEX_H
2 #define _ASM_POWERPC_TIMEX_H
3 
4 #ifdef __KERNEL__
5 
6 /*
7  * PowerPC architecture timex specifications
8  */
9 
10 #include <asm/cputable.h>
11 #include <asm/reg.h>
12 
13 #define CLOCK_TICK_RATE	1024000 /* Underlying HZ */
14 
15 typedef unsigned long cycles_t;
16 
17 static inline cycles_t get_cycles(void)
18 {
19 #ifdef __powerpc64__
20 	return mftb();
21 #else
22 	cycles_t ret;
23 
24 	/*
25 	 * For the "cycle" counter we use the timebase lower half.
26 	 * Currently only used on SMP.
27 	 */
28 
29 	ret = 0;
30 
31 	__asm__ __volatile__(
32 #ifdef CONFIG_8xx
33 		"97:	mftb %0\n"
34 #else
35 		"97:	mfspr %0, %2\n"
36 #endif
37 		"99:\n"
38 		".section __ftr_fixup,\"a\"\n"
39 		".align 2\n"
40 		"98:\n"
41 		"	.long %1\n"
42 		"	.long 0\n"
43 		"	.long 97b-98b\n"
44 		"	.long 99b-98b\n"
45 		"	.long 0\n"
46 		"	.long 0\n"
47 		".previous"
48 #ifdef CONFIG_8xx
49 		: "=r" (ret) : "i" (CPU_FTR_601));
50 #else
51 		: "=r" (ret) : "i" (CPU_FTR_601), "i" (SPRN_TBRL));
52 #endif
53 	return ret;
54 #endif
55 }
56 
57 #endif	/* __KERNEL__ */
58 #endif	/* _ASM_POWERPC_TIMEX_H */
59