/* calibrate.c: default delay calibration * * Excised from init/main.c * Copyright (C) 1991, 1992 Linus Torvalds */ #include #include #include #include static unsigned long preset_lpj; static int __init lpj_setup(char *str) { preset_lpj = simple_strtoul(str,NULL,0); return 1; } __setup("lpj=", lpj_setup); #ifdef ARCH_HAS_READ_CURRENT_TIMER /* This routine uses the read_current_timer() routine and gets the * loops per jiffy directly, instead of guessing it using delay(). * Also, this code tries to handle non-maskable asynchronous events * (like SMIs) */ #define DELAY_CALIBRATION_TICKS ((HZ < 100) ? 1 : (HZ/100)) #define MAX_DIRECT_CALIBRATION_RETRIES 5 static unsigned long __devinit calibrate_delay_direct(void) { unsigned long pre_start, start, post_start; unsigned long pre_end, end, post_end; unsigned long start_jiffies; unsigned long tsc_rate_min, tsc_rate_max; unsigned long good_tsc_sum = 0; unsigned long good_tsc_count = 0; int i; if (read_current_timer(&pre_start) < 0 ) return 0; /* * A simple loop like * while ( jiffies < start_jiffies+1) * start = read_current_timer(); * will not do. As we don't really know whether jiffy switch * happened first or timer_value was read first. And some asynchronous * event can happen between these two events introducing errors in lpj. * * So, we do * 1. pre_start <- When we are sure that jiffy switch hasn't happened * 2. check jiffy switch * 3. start <- timer value before or after jiffy switch * 4. post_start <- When we are sure that jiffy switch has happened * * Note, we don't know anything about order of 2 and 3. * Now, by looking at post_start and pre_start difference, we can * check whether any asynchronous event happened or not */ for (i = 0; i < MAX_DIRECT_CALIBRATION_RETRIES; i++) { pre_start = 0; read_current_timer(&start); start_jiffies = jiffies; while (jiffies <= (start_jiffies + 1)) { pre_start = start; read_current_timer(&start); } read_current_timer(&post_start); pre_end = 0; end = post_start; while (jiffies <= (start_jiffies + 1 + DELAY_CALIBRATION_TICKS)) { pre_end = end; read_current_timer(&end); } read_current_timer(&post_end); tsc_rate_max = (post_end - pre_start) / DELAY_CALIBRATION_TICKS; tsc_rate_min = (pre_end - post_start) / DELAY_CALIBRATION_TICKS; /* * If the upper limit and lower limit of the tsc_rate is * >= 12.5% apart, redo calibration. */ if (pre_start != 0 && pre_end != 0 && (tsc_rate_max - tsc_rate_min) < (tsc_rate_max >> 3)) { good_tsc_count++; good_tsc_sum += tsc_rate_max; } } if (good_tsc_count) return (good_tsc_sum/good_tsc_count); printk(KERN_WARNING "calibrate_delay_direct() failed to get a good " "estimate for loops_per_jiffy.\nProbably due to long platform interrupts. Consider using \"lpj=\" boot option.\n"); return 0; } #else static unsigned long __devinit calibrate_delay_direct(void) {return 0;} #endif /* * This is the number of bits of precision for the loops_per_jiffy. Each * bit takes on average 1.5/HZ seconds. This (like the original) is a little * better than 1% */ #define LPS_PREC 8 void __devinit calibrate_delay(void) { unsigned long ticks, loopbit; int lps_precision = LPS_PREC; if (preset_lpj) { loops_per_jiffy = preset_lpj; printk("Calibrating delay loop (skipped)... " "%lu.%02lu BogoMIPS preset\n", loops_per_jiffy/(500000/HZ), (loops_per_jiffy/(5000/HZ)) % 100); } else if ((loops_per_jiffy = calibrate_delay_direct()) != 0) { printk("Calibrating delay using timer specific routine.. "); printk("%lu.%02lu BogoMIPS (lpj=%lu)\n", loops_per_jiffy/(500000/HZ), (loops_per_jiffy/(5000/HZ)) % 100, loops_per_jiffy); } else { loops_per_jiffy = (1<<12); printk(KERN_DEBUG "Calibrating delay loop... "); while ((loops_per_jiffy <<= 1) != 0) { /* wait for "start of" clock tick */ ticks = jiffies; while (ticks == jiffies) /* nothing */; /* Go .. */ ticks = jiffies; __delay(loops_per_jiffy); ticks = jiffies - ticks; if (ticks) break; } /* * Do a binary approximation to get loops_per_jiffy set to * equal one clock (up to lps_precision bits) */ loops_per_jiffy >>= 1; loopbit = loops_per_jiffy; while (lps_precision-- && (loopbit >>= 1)) { loops_per_jiffy |= loopbit; ticks = jiffies; while (ticks == jiffies) /* nothing */; ticks = jiffies; __delay(loops_per_jiffy); if (jiffies != ticks) /* longer than 1 tick */ loops_per_jiffy &= ~loopbit; } /* Round the value and print it */ printk("%lu.%02lu BogoMIPS (lpj=%lu)\n", loops_per_jiffy/(500000/HZ), (loops_per_jiffy/(5000/HZ)) % 100, loops_per_jiffy); } } >feature/onemsi Unnamed repository; edit this file to name it for gitweb.root
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6 daysadd translation files for Santali (Ol-Chiki) (sat-Olck)HEADmasterChristian Lohmaier158-0/+284480
6 daysupdate translations for master/25.2.0 alpha1Christian Lohmaier1216-130450/+143164
7 daysUpdated Slovenian translationMartin Srebotnjak64-13501/+19617
9 daysupdate translations for master / 25.2 alpha1Christian Lohmaier1934-72263/+100204
2024-11-05update translations for masterChristian Lohmaier2013-339716/+413548
2024-10-25update translations for masterChristian Lohmaier248-8678/+9001
2024-10-23add Tagalog (tl) translationsChristian Lohmaier220-0/+789621
2024-10-23update translations for masterChristian Lohmaier1725-190947/+231197
2024-10-04update translations for masterChristian Lohmaier2839-243555/+298302
2024-09-17update translations for masterChristian Lohmaier4999-1016811/+1482054
2024-09-06update translations for 24.8.1 rc2Christian Lohmaier294-4826/+4802
2024-08-23update translations for 24.8.1 rc1Christian Lohmaier464-7996/+9278
2024-08-08update translations for 24.8.0 rc3Christian Lohmaier330-7999/+7194
2024-07-26update translations for 24.8.0 rc2/masterChristian Lohmaier78-778/+848
2024-07-24update translations for 24.8.0 rc2Christian Lohmaier334-5629/+5300
2024-07-15update translations for master/24-8Christian Lohmaier449-6941/+7245
2024-07-08update translations for 24.8.0 rc1/masterChristian Lohmaier752-13300/+15854
2024-07-07Updated Slovenian translationMartin Srebotnjak40-2210/+2458
2024-06-28update translations for 24.8/masterChristian Lohmaier1401-55124/+51822
2024-06-20update translations for 24-8/masterChristian Lohmaier696-19433/+27756
2024-06-20Updated Slovenian translationMartin Srebotnjak39-1188/+1555
2024-06-17update translations for 24-8/masterChristian Lohmaier888-57427/+58764
2024-06-11update translations for master / 24.8.0 beta1libreoffice-24-8-branch-pointChristian Lohmaier1034-10831/+33947
2024-06-06update translations for master / 24.8.0 beta1Christian Lohmaier