diff options
Diffstat (limited to 'ANDROID_3.4.5/arch/x86/lib/delay.c')
-rw-r--r-- | ANDROID_3.4.5/arch/x86/lib/delay.c | 140 |
1 files changed, 0 insertions, 140 deletions
diff --git a/ANDROID_3.4.5/arch/x86/lib/delay.c b/ANDROID_3.4.5/arch/x86/lib/delay.c deleted file mode 100644 index e395693a..00000000 --- a/ANDROID_3.4.5/arch/x86/lib/delay.c +++ /dev/null @@ -1,140 +0,0 @@ -/* - * Precise Delay Loops for i386 - * - * Copyright (C) 1993 Linus Torvalds - * Copyright (C) 1997 Martin Mares <mj@atrey.karlin.mff.cuni.cz> - * Copyright (C) 2008 Jiri Hladky <hladky _dot_ jiri _at_ gmail _dot_ com> - * - * The __delay function must _NOT_ be inlined as its execution time - * depends wildly on alignment on many x86 processors. The additional - * jump magic is needed to get the timing stable on all the CPU's - * we have to worry about. - */ - -#include <linux/module.h> -#include <linux/sched.h> -#include <linux/timex.h> -#include <linux/preempt.h> -#include <linux/delay.h> -#include <linux/init.h> - -#include <asm/processor.h> -#include <asm/delay.h> -#include <asm/timer.h> - -#ifdef CONFIG_SMP -# include <asm/smp.h> -#endif - -/* simple loop based delay: */ -static void delay_loop(unsigned long loops) -{ - asm volatile( - " test %0,%0 \n" - " jz 3f \n" - " jmp 1f \n" - - ".align 16 \n" - "1: jmp 2f \n" - - ".align 16 \n" - "2: dec %0 \n" - " jnz 2b \n" - "3: dec %0 \n" - - : /* we don't need output */ - :"a" (loops) - ); -} - -/* TSC based delay: */ -static void delay_tsc(unsigned long __loops) -{ - u32 bclock, now, loops = __loops; - int cpu; - - preempt_disable(); - cpu = smp_processor_id(); - rdtsc_barrier(); - rdtscl(bclock); - for (;;) { - rdtsc_barrier(); - rdtscl(now); - if ((now - bclock) >= loops) - break; - - /* Allow RT tasks to run */ - preempt_enable(); - rep_nop(); - preempt_disable(); - - /* - * It is possible that we moved to another CPU, and - * since TSC's are per-cpu we need to calculate - * that. The delay must guarantee that we wait "at - * least" the amount of time. Being moved to another - * CPU could make the wait longer but we just need to - * make sure we waited long enough. Rebalance the - * counter for this CPU. - */ - if (unlikely(cpu != smp_processor_id())) { - loops -= (now - bclock); - cpu = smp_processor_id(); - rdtsc_barrier(); - rdtscl(bclock); - } - } - preempt_enable(); -} - -/* - * Since we calibrate only once at boot, this - * function should be set once at boot and not changed - */ -static void (*delay_fn)(unsigned long) = delay_loop; - -void use_tsc_delay(void) -{ - delay_fn = delay_tsc; -} - -int __devinit read_current_timer(unsigned long *timer_val) -{ - if (delay_fn == delay_tsc) { - rdtscll(*timer_val); - return 0; - } - return -1; -} - -void __delay(unsigned long loops) -{ - delay_fn(loops); -} -EXPORT_SYMBOL(__delay); - -inline void __const_udelay(unsigned long xloops) -{ - int d0; - - xloops *= 4; - asm("mull %%edx" - :"=d" (xloops), "=&a" (d0) - :"1" (xloops), "0" - (this_cpu_read(cpu_info.loops_per_jiffy) * (HZ/4))); - - __delay(++xloops); -} -EXPORT_SYMBOL(__const_udelay); - -void __udelay(unsigned long usecs) -{ - __const_udelay(usecs * 0x000010c7); /* 2**32 / 1000000 (rounded up) */ -} -EXPORT_SYMBOL(__udelay); - -void __ndelay(unsigned long nsecs) -{ - __const_udelay(nsecs * 0x00005); /* 2**32 / 1000000000 (rounded up) */ -} -EXPORT_SYMBOL(__ndelay); |