diff options
Diffstat (limited to 'drivers/cpuidle/cpuidle-pseries.c')
| -rw-r--r-- | drivers/cpuidle/cpuidle-pseries.c | 18 |
1 files changed, 16 insertions, 2 deletions
diff --git a/drivers/cpuidle/cpuidle-pseries.c b/drivers/cpuidle/cpuidle-pseries.c index a2b5c6f60cf0..ff164dec8422 100644 --- a/drivers/cpuidle/cpuidle-pseries.c +++ b/drivers/cpuidle/cpuidle-pseries.c @@ -402,7 +402,7 @@ static void __init fixup_cede0_latency(void) * pseries_idle_probe() * Choose state table for shared versus dedicated partition */ -static int pseries_idle_probe(void) +static int __init pseries_idle_probe(void) { if (cpuidle_disable != IDLE_NO_OVERRIDE) @@ -419,7 +419,21 @@ static int pseries_idle_probe(void) cpuidle_state_table = shared_states; max_idle_state = ARRAY_SIZE(shared_states); } else { - fixup_cede0_latency(); + /* + * Use firmware provided latency values + * starting with POWER10 platforms. In the + * case that we are running on a POWER10 + * platform but in an earlier compat mode, we + * can still use the firmware provided values. + * + * However, on platforms prior to POWER10, we + * cannot rely on the accuracy of the firmware + * provided latency values. On such platforms, + * go with the conservative default estimate + * of 10us. + */ + if (cpu_has_feature(CPU_FTR_ARCH_31) || pvr_version_is(PVR_POWER10)) + fixup_cede0_latency(); cpuidle_state_table = dedicated_states; max_idle_state = NR_DEDICATED_STATES; } |