• Mattia Dongili's avatar
    [CPUFREQ] Measure transition latency at driver initialization · 1a10760c
    Mattia Dongili authored
    The attached patch introduces runtime latency measurement for ICH[234]
    based chipsets instead of using CPUFREQ_ETERNAL. It includes
    some sanity checks in case the measured value is out of range and
    assigns a safe value of 500uSec that should still be enough on
    problematics chipsets (current testing report values ~200uSec). The
    measurement is currently done in speedstep_get_freqs in order to avoid
    further unnecessary transitions and in the hope it'll come handy for SMI
    also.
    Signed-off-by: default avatarMattia Dongili <malattia@linux.it>
    Acked-by: default avatarDominik Brodowski <linux@dominikbrodowski.net>
    Signed-off-by: default avatarDave Jones <davej@redhat.com>
    
     speedstep-ich.c |    4 ++--
     speedstep-lib.c |   32 +++++++++++++++++++++++++++++++-
     speedstep-lib.h |    1 +
     speedstep-smi.c |    1 +
     4 files changed, 35 insertions(+), 3 deletions(-)
    1a10760c
speedstep-ich.c 10.4 KB