Rev 948 | Details | Compare with Previous | Last modification | View Log | RSS feed
| Rev | Author | Line No. | Line |
|---|---|---|---|
| 1063 | tullio | 1 | |
| 2 | /* |
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| 3 | * This program is free software; you can redistribute it and/or modify |
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| 4 | * it under the terms of the GNU General Public License as published by |
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| 5 | * the Free Software Foundation; either version 2 of the License, or |
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| 6 | * (at your option) any later version. |
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| 7 | * |
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| 8 | * This program is distributed in the hope that it will be useful, |
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| 9 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
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| 10 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
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| 11 | * GNU General Public License for more details. |
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| 12 | * |
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| 13 | * You should have received a copy of the GNU General Public License |
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| 14 | * along with this program; if not, write to the Free Software |
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| 15 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
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| 16 | * |
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| 17 | */ |
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| 18 | |||
| 948 | trimarchi | 19 | #include "kernel/kern.h" |
| 20 | #include "calibrate.h" |
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| 21 | |||
| 22 | int cal_cycles=0; |
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| 23 | |||
| 24 | /* Runtime Calibration */ |
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| 25 | int calibrate_cycle() |
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| 26 | { |
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| 27 | long long i; |
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| 28 | struct timespec start,end,diff; |
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| 29 | |||
| 30 | if (cal_cycles != 0) return 0; |
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| 31 | |||
| 32 | |||
| 33 | |||
| 34 | kern_cli(); |
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| 35 | __asm__ __volatile__ ("xorl %%eax,%%eax\n\t" |
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| 36 | "cpuid\n\t" |
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| 37 | :::"eax","ebx","ecx","edx"); |
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| 38 | kern_gettime(&start); |
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| 39 | for (i=0;i<CALIBRATION_DELTA;i++) |
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| 40 | __asm__ __volatile__ ("xorl %%eax,%%eax\n\t" |
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| 41 | "cpuid\n\t" |
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| 42 | :::"eax","ebx","ecx","edx"); |
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| 43 | __asm__ __volatile__ ("xorl %%eax,%%eax\n\t" |
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| 44 | "cpuid\n\t" |
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| 45 | :::"eax","ebx","ecx","edx"); |
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| 46 | kern_gettime(&end); |
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| 47 | kern_sti(); |
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| 48 | |||
| 49 | SUBTIMESPEC(&end,&start,&diff); |
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| 50 | cal_cycles = TIMESPEC2USEC(&diff); |
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| 51 | |||
| 52 | cprintf("Calibration usec/[%d cycles] = %d\n",CALIBRATION_DELTA,cal_cycles); |
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| 53 | |||
| 54 | return 0; |
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| 55 | |||
| 56 | } |
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| 57 | |||
| 58 | void eat(TIME wait) { |
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| 59 | |||
| 60 | int exec_cycles=0; |
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| 61 | int i=0; |
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| 62 | |||
| 63 | exec_cycles = (long long)(wait) * CALIBRATION_DELTA / cal_cycles; |
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| 64 | |||
| 65 | /* Execution delay */ |
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| 66 | for (i=0;i<exec_cycles;i++) |
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| 67 | __asm__ __volatile__ ("xorl %%eax,%%eax\n\t" |
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| 68 | "cpuid\n\t" |
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| 69 | :::"eax","ebx","ecx","edx"); |
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| 70 | |||
| 71 | } |