diff options
Diffstat (limited to 'init/calibrate.c')
| -rw-r--r-- | init/calibrate.c | 15 |
1 files changed, 15 insertions, 0 deletions
diff --git a/init/calibrate.c b/init/calibrate.c index 24df7976816c..5f117ca9e069 100644 --- a/init/calibrate.c +++ b/init/calibrate.c @@ -246,6 +246,19 @@ recalibrate: static DEFINE_PER_CPU(unsigned long, cpu_loops_per_jiffy) = { 0 }; +/* + * Check if cpu calibration delay is already known. For example, + * some processors with multi-core sockets may have all cores + * with the same calibration delay. + * + * Architectures should override this function if a faster calibration + * method is available. + */ +unsigned long __attribute__((weak)) __cpuinit calibrate_delay_is_known(void) +{ + return 0; +} + void __cpuinit calibrate_delay(void) { unsigned long lpj; @@ -265,6 +278,8 @@ void __cpuinit calibrate_delay(void) lpj = lpj_fine; pr_info("Calibrating delay loop (skipped), " "value calculated using timer frequency.. "); + } else if ((lpj = calibrate_delay_is_known())) { + ; } else if ((lpj = calibrate_delay_direct()) != 0) { if (!printed) pr_info("Calibrating delay using timer " |