Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Common time prototypes and such for all ppc machines. |
| 3 | * |
| 4 | * Written by Cort Dougan (cort@fsmlabs.com) to merge |
| 5 | * Paul Mackerras' version and mine for PReP and Pmac. |
| 6 | */ |
| 7 | |
| 8 | #ifdef __KERNEL__ |
| 9 | #ifndef __ASM_TIME_H__ |
| 10 | #define __ASM_TIME_H__ |
| 11 | |
| 12 | #include <linux/config.h> |
| 13 | #include <linux/types.h> |
| 14 | #include <linux/rtc.h> |
| 15 | #include <linux/threads.h> |
| 16 | |
| 17 | #include <asm/reg.h> |
| 18 | |
| 19 | /* time.c */ |
| 20 | extern unsigned tb_ticks_per_jiffy; |
| 21 | extern unsigned tb_to_us; |
| 22 | extern unsigned tb_last_stamp; |
| 23 | extern unsigned long disarm_decr[NR_CPUS]; |
| 24 | |
| 25 | extern void to_tm(int tim, struct rtc_time * tm); |
| 26 | extern time_t last_rtc_update; |
| 27 | |
| 28 | extern void set_dec_cpu6(unsigned int val); |
| 29 | |
| 30 | int via_calibrate_decr(void); |
| 31 | |
| 32 | /* Accessor functions for the decrementer register. |
| 33 | * The 4xx doesn't even have a decrementer. I tried to use the |
| 34 | * generic timer interrupt code, which seems OK, with the 4xx PIT |
| 35 | * in auto-reload mode. The problem is PIT stops counting when it |
| 36 | * hits zero. If it would wrap, we could use it just like a decrementer. |
| 37 | */ |
| 38 | static __inline__ unsigned int get_dec(void) |
| 39 | { |
| 40 | #if defined(CONFIG_40x) |
| 41 | return (mfspr(SPRN_PIT)); |
| 42 | #else |
| 43 | return (mfspr(SPRN_DEC)); |
| 44 | #endif |
| 45 | } |
| 46 | |
| 47 | static __inline__ void set_dec(unsigned int val) |
| 48 | { |
| 49 | #if defined(CONFIG_40x) |
| 50 | return; /* Have to let it auto-reload */ |
| 51 | #elif defined(CONFIG_8xx_CPU6) |
| 52 | set_dec_cpu6(val); |
| 53 | #else |
| 54 | mtspr(SPRN_DEC, val); |
| 55 | #endif |
| 56 | } |
| 57 | |
| 58 | /* Accessor functions for the timebase (RTC on 601) registers. */ |
| 59 | /* If one day CONFIG_POWER is added just define __USE_RTC as 1 */ |
| 60 | #ifdef CONFIG_6xx |
| 61 | extern __inline__ int const __USE_RTC(void) { |
| 62 | return (mfspr(SPRN_PVR)>>16) == 1; |
| 63 | } |
| 64 | #else |
| 65 | #define __USE_RTC() 0 |
| 66 | #endif |
| 67 | |
| 68 | extern __inline__ unsigned long get_tbl(void) { |
| 69 | unsigned long tbl; |
| 70 | #if defined(CONFIG_403GCX) |
| 71 | asm volatile("mfspr %0, 0x3dd" : "=r" (tbl)); |
| 72 | #else |
| 73 | asm volatile("mftb %0" : "=r" (tbl)); |
| 74 | #endif |
| 75 | return tbl; |
| 76 | } |
| 77 | |
| 78 | extern __inline__ unsigned long get_tbu(void) { |
| 79 | unsigned long tbl; |
| 80 | #if defined(CONFIG_403GCX) |
| 81 | asm volatile("mfspr %0, 0x3dc" : "=r" (tbl)); |
| 82 | #else |
| 83 | asm volatile("mftbu %0" : "=r" (tbl)); |
| 84 | #endif |
| 85 | return tbl; |
| 86 | } |
| 87 | |
| 88 | extern __inline__ void set_tb(unsigned int upper, unsigned int lower) |
| 89 | { |
| 90 | mtspr(SPRN_TBWL, 0); |
| 91 | mtspr(SPRN_TBWU, upper); |
| 92 | mtspr(SPRN_TBWL, lower); |
| 93 | } |
| 94 | |
| 95 | extern __inline__ unsigned long get_rtcl(void) { |
| 96 | unsigned long rtcl; |
| 97 | asm volatile("mfrtcl %0" : "=r" (rtcl)); |
| 98 | return rtcl; |
| 99 | } |
| 100 | |
| 101 | extern __inline__ unsigned long get_rtcu(void) |
| 102 | { |
| 103 | unsigned long rtcu; |
| 104 | asm volatile("mfrtcu %0" : "=r" (rtcu)); |
| 105 | return rtcu; |
| 106 | } |
| 107 | |
| 108 | extern __inline__ unsigned get_native_tbl(void) { |
| 109 | if (__USE_RTC()) |
| 110 | return get_rtcl(); |
| 111 | else |
| 112 | return get_tbl(); |
| 113 | } |
| 114 | |
| 115 | /* On machines with RTC, this function can only be used safely |
| 116 | * after the timestamp and for 1 second. It is only used by gettimeofday |
| 117 | * however so it should not matter. |
| 118 | */ |
| 119 | extern __inline__ unsigned tb_ticks_since(unsigned tstamp) { |
| 120 | if (__USE_RTC()) { |
| 121 | int delta = get_rtcl() - tstamp; |
| 122 | return delta<0 ? delta + 1000000000 : delta; |
| 123 | } else { |
| 124 | return get_tbl() - tstamp; |
| 125 | } |
| 126 | } |
| 127 | |
| 128 | #if 0 |
| 129 | extern __inline__ unsigned long get_bin_rtcl(void) { |
| 130 | unsigned long rtcl, rtcu1, rtcu2; |
| 131 | asm volatile("\ |
| 132 | 1: mfrtcu %0\n\ |
| 133 | mfrtcl %1\n\ |
| 134 | mfrtcu %2\n\ |
| 135 | cmpw %0,%2\n\ |
| 136 | bne- 1b\n" |
| 137 | : "=r" (rtcu1), "=r" (rtcl), "=r" (rtcu2) |
| 138 | : : "cr0"); |
| 139 | return rtcu2*1000000000+rtcl; |
| 140 | } |
| 141 | |
| 142 | extern __inline__ unsigned binary_tbl(void) { |
| 143 | if (__USE_RTC()) |
| 144 | return get_bin_rtcl(); |
| 145 | else |
| 146 | return get_tbl(); |
| 147 | } |
| 148 | #endif |
| 149 | |
| 150 | /* Use mulhwu to scale processor timebase to timeval */ |
| 151 | /* Specifically, this computes (x * y) / 2^32. -- paulus */ |
| 152 | #define mulhwu(x,y) \ |
| 153 | ({unsigned z; asm ("mulhwu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;}) |
| 154 | |
| 155 | unsigned mulhwu_scale_factor(unsigned, unsigned); |
| 156 | #endif /* __ASM_TIME_H__ */ |
| 157 | #endif /* __KERNEL__ */ |