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33215652e4
a bunch of functions switched from volatile to __attribute__((noreturn)) and from const to __attribute_pure__ Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
158 lines
3.7 KiB
C
158 lines
3.7 KiB
C
/*
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* Common time prototypes and such for all ppc machines.
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*
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* Written by Cort Dougan (cort@fsmlabs.com) to merge
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* Paul Mackerras' version and mine for PReP and Pmac.
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*/
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#ifdef __KERNEL__
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#ifndef __ASM_TIME_H__
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#define __ASM_TIME_H__
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#include <linux/config.h>
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#include <linux/types.h>
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#include <linux/rtc.h>
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#include <linux/threads.h>
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#include <asm/reg.h>
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/* time.c */
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extern unsigned tb_ticks_per_jiffy;
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extern unsigned tb_to_us;
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extern unsigned tb_last_stamp;
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extern unsigned long disarm_decr[NR_CPUS];
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extern void to_tm(int tim, struct rtc_time * tm);
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extern time_t last_rtc_update;
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extern void set_dec_cpu6(unsigned int val);
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int via_calibrate_decr(void);
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/* Accessor functions for the decrementer register.
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* The 4xx doesn't even have a decrementer. I tried to use the
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* generic timer interrupt code, which seems OK, with the 4xx PIT
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* in auto-reload mode. The problem is PIT stops counting when it
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* hits zero. If it would wrap, we could use it just like a decrementer.
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*/
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static __inline__ unsigned int get_dec(void)
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{
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#if defined(CONFIG_40x)
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return (mfspr(SPRN_PIT));
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#else
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return (mfspr(SPRN_DEC));
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#endif
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}
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static __inline__ void set_dec(unsigned int val)
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{
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#if defined(CONFIG_40x)
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return; /* Have to let it auto-reload */
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#elif defined(CONFIG_8xx_CPU6)
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set_dec_cpu6(val);
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#else
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mtspr(SPRN_DEC, val);
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#endif
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}
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/* Accessor functions for the timebase (RTC on 601) registers. */
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/* If one day CONFIG_POWER is added just define __USE_RTC as 1 */
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#ifdef CONFIG_6xx
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extern __inline__ int __attribute_pure__ __USE_RTC(void) {
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return (mfspr(SPRN_PVR)>>16) == 1;
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}
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#else
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#define __USE_RTC() 0
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#endif
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extern __inline__ unsigned long get_tbl(void) {
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unsigned long tbl;
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#if defined(CONFIG_403GCX)
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asm volatile("mfspr %0, 0x3dd" : "=r" (tbl));
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#else
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asm volatile("mftb %0" : "=r" (tbl));
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#endif
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return tbl;
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}
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extern __inline__ unsigned long get_tbu(void) {
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unsigned long tbl;
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#if defined(CONFIG_403GCX)
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asm volatile("mfspr %0, 0x3dc" : "=r" (tbl));
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#else
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asm volatile("mftbu %0" : "=r" (tbl));
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#endif
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return tbl;
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}
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extern __inline__ void set_tb(unsigned int upper, unsigned int lower)
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{
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mtspr(SPRN_TBWL, 0);
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mtspr(SPRN_TBWU, upper);
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mtspr(SPRN_TBWL, lower);
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}
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extern __inline__ unsigned long get_rtcl(void) {
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unsigned long rtcl;
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asm volatile("mfrtcl %0" : "=r" (rtcl));
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return rtcl;
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}
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extern __inline__ unsigned long get_rtcu(void)
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{
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unsigned long rtcu;
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asm volatile("mfrtcu %0" : "=r" (rtcu));
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return rtcu;
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}
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extern __inline__ unsigned get_native_tbl(void) {
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if (__USE_RTC())
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return get_rtcl();
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else
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return get_tbl();
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}
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/* On machines with RTC, this function can only be used safely
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* after the timestamp and for 1 second. It is only used by gettimeofday
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* however so it should not matter.
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*/
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extern __inline__ unsigned tb_ticks_since(unsigned tstamp) {
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if (__USE_RTC()) {
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int delta = get_rtcl() - tstamp;
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return delta<0 ? delta + 1000000000 : delta;
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} else {
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return get_tbl() - tstamp;
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}
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}
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#if 0
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extern __inline__ unsigned long get_bin_rtcl(void) {
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unsigned long rtcl, rtcu1, rtcu2;
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asm volatile("\
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1: mfrtcu %0\n\
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mfrtcl %1\n\
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mfrtcu %2\n\
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cmpw %0,%2\n\
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bne- 1b\n"
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: "=r" (rtcu1), "=r" (rtcl), "=r" (rtcu2)
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: : "cr0");
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return rtcu2*1000000000+rtcl;
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}
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extern __inline__ unsigned binary_tbl(void) {
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if (__USE_RTC())
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return get_bin_rtcl();
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else
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return get_tbl();
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}
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#endif
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/* Use mulhwu to scale processor timebase to timeval */
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/* Specifically, this computes (x * y) / 2^32. -- paulus */
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#define mulhwu(x,y) \
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({unsigned z; asm ("mulhwu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;})
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unsigned mulhwu_scale_factor(unsigned, unsigned);
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#endif /* __ASM_TIME_H__ */
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#endif /* __KERNEL__ */
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