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author | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2019-11-26 10:26:26 +0100 |
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committer | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2019-11-26 10:26:26 +0100 |
commit | 62214039525a621aa0eca3fe9160e809ec0e45d3 (patch) | |
tree | 14c8d2c95c75382628a7a3ed2fca223c42c28602 /drivers/acpi | |
parent | 05ff1ba412fd6bd48d56dd4c0baff626533728cc (diff) | |
parent | 5aa9ba6312e36c18626e73506b92d1513d815435 (diff) | |
download | linux-62214039525a621aa0eca3fe9160e809ec0e45d3.tar.bz2 |
Merge branch 'pm-cpuidle'
* pm-cpuidle:
cpuidle: Pass exit latency limit to cpuidle_use_deepest_state()
cpuidle: Allow idle injection to apply exit latency limit
cpuidle: Introduce cpuidle_driver_state_disabled() for driver quirks
cpuidle: teo: Avoid code duplication in conditionals
cpuidle: teo: Avoid using "early hits" incorrectly
cpuidle: teo: Exclude cpuidle overhead from computations
cpuidle: Use nanoseconds as the unit of time
cpuidle: Consolidate disabled state checks
ACPI: processor_idle: Skip dummy wait if kernel is in guest
cpuidle: Do not unset the driver if it is there already
cpuidle: teo: Fix "early hits" handling for disabled idle states
cpuidle: teo: Consider hits and misses metrics of disabled states
cpuidle: teo: Rename local variable in teo_select()
cpuidle: teo: Ignore disabled idle states that are too deep
Diffstat (limited to 'drivers/acpi')
-rw-r--r-- | drivers/acpi/processor_idle.c | 21 |
1 files changed, 15 insertions, 6 deletions
diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c index ed56c6d20b08..2ae95df2e74f 100644 --- a/drivers/acpi/processor_idle.c +++ b/drivers/acpi/processor_idle.c @@ -642,6 +642,19 @@ static int acpi_idle_bm_check(void) return bm_status; } +static void wait_for_freeze(void) +{ +#ifdef CONFIG_X86 + /* No delay is needed if we are in guest */ + if (boot_cpu_has(X86_FEATURE_HYPERVISOR)) + return; +#endif + /* Dummy wait op - must do something useless after P_LVL2 read + because chipsets cannot guarantee that STPCLK# signal + gets asserted in time to freeze execution properly. */ + inl(acpi_gbl_FADT.xpm_timer_block.address); +} + /** * acpi_idle_do_entry - enter idle state using the appropriate method * @cx: cstate data @@ -658,10 +671,7 @@ static void __cpuidle acpi_idle_do_entry(struct acpi_processor_cx *cx) } else { /* IO port based C-state */ inb(cx->address); - /* Dummy wait op - must do something useless after P_LVL2 read - because chipsets cannot guarantee that STPCLK# signal - gets asserted in time to freeze execution properly. */ - inl(acpi_gbl_FADT.xpm_timer_block.address); + wait_for_freeze(); } } @@ -682,8 +692,7 @@ static int acpi_idle_play_dead(struct cpuidle_device *dev, int index) safe_halt(); else if (cx->entry_method == ACPI_CSTATE_SYSTEMIO) { inb(cx->address); - /* See comment in acpi_idle_do_entry() */ - inl(acpi_gbl_FADT.xpm_timer_block.address); + wait_for_freeze(); } else return -ENODEV; } |