aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/acpi
diff options
context:
space:
mode:
authorRafael J. Wysocki <rafael.j.wysocki@intel.com>2019-11-26 10:26:26 +0100
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>2019-11-26 10:26:26 +0100
commit62214039525a621aa0eca3fe9160e809ec0e45d3 (patch)
tree14c8d2c95c75382628a7a3ed2fca223c42c28602 /drivers/acpi
parentPM: QoS: Invalidate frequency QoS requests after removal (diff)
parentcpuidle: Pass exit latency limit to cpuidle_use_deepest_state() (diff)
downloadlinux-dev-62214039525a621aa0eca3fe9160e809ec0e45d3.tar.xz
linux-dev-62214039525a621aa0eca3fe9160e809ec0e45d3.zip
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.c21
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;
}