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| Rev | Author | Line No. | Line |
|---|---|---|---|
| 948 | trimarchi | 1 | #include "kernel/kern.h" |
| 2 | #include "calibrate.h" |
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| 3 | |||
| 4 | int cal_cycles=0; |
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| 5 | |||
| 6 | /* Runtime Calibration */ |
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| 7 | int calibrate_cycle() |
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| 8 | { |
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| 9 | long long i; |
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| 10 | struct timespec start,end,diff; |
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| 11 | |||
| 12 | if (cal_cycles != 0) return 0; |
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| 13 | |||
| 14 | |||
| 15 | |||
| 16 | kern_cli(); |
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| 17 | __asm__ __volatile__ ("xorl %%eax,%%eax\n\t" |
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| 18 | "cpuid\n\t" |
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| 19 | :::"eax","ebx","ecx","edx"); |
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| 20 | kern_gettime(&start); |
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| 21 | for (i=0;i<CALIBRATION_DELTA;i++) |
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| 22 | __asm__ __volatile__ ("xorl %%eax,%%eax\n\t" |
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| 23 | "cpuid\n\t" |
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| 24 | :::"eax","ebx","ecx","edx"); |
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| 25 | __asm__ __volatile__ ("xorl %%eax,%%eax\n\t" |
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| 26 | "cpuid\n\t" |
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| 27 | :::"eax","ebx","ecx","edx"); |
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| 28 | kern_gettime(&end); |
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| 29 | kern_sti(); |
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| 30 | |||
| 31 | SUBTIMESPEC(&end,&start,&diff); |
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| 32 | cal_cycles = TIMESPEC2USEC(&diff); |
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| 33 | |||
| 34 | cprintf("Calibration usec/[%d cycles] = %d\n",CALIBRATION_DELTA,cal_cycles); |
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| 35 | |||
| 36 | return 0; |
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| 37 | |||
| 38 | } |
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| 39 | |||
| 40 | void eat(TIME wait) { |
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| 41 | |||
| 42 | int exec_cycles=0; |
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| 43 | int i=0; |
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| 44 | |||
| 45 | exec_cycles = (long long)(wait) * CALIBRATION_DELTA / cal_cycles; |
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| 46 | |||
| 47 | /* Execution delay */ |
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| 48 | for (i=0;i<exec_cycles;i++) |
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| 49 | __asm__ __volatile__ ("xorl %%eax,%%eax\n\t" |
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| 50 | "cpuid\n\t" |
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| 51 | :::"eax","ebx","ecx","edx"); |
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| 52 | |||
| 53 | } |