platform/x86: amd-pmc: Set QOS during suspend on CZN w/ timer wakeup
commit 59348401 ("platform/x86: amd-pmc: Add special handling for timer based S0i3 wakeup") adds support for using another platform timer in lieu of the RTC which doesn't work properly on some systems. This path was validated and worked well before submission. During the 5.16-rc1 merge window other patches were merged that caused this to stop working properly. When this feature was used with 5.16-rc1 or later some OEM laptops with the matching firmware requirements from that commit would shutdown instead of program a timer based wakeup. This was bisected to commit 8d89835b ("PM: suspend: Do not pause cpuidle in the suspend-to-idle path"). This wasn't supposed to cause any negative impacts and also tested well on both Intel and ARM platforms. However this changed the semantics of when CPUs are allowed to be in the deepest state. For the AMD systems in question it appears this causes a firmware crash for timer based wakeup. It's hypothesized to be caused by the `amd-pmc` driver sending `OS_HINT` and all the CPUs going into a deep state while the timer is still being programmed. It's likely a firmware bug, but to avoid it don't allow setting CPUs into the deepest state while using CZN timer wakeup path. If later it's discovered that this also occurs from "regular" suspends without a timer as well or on other silicon, this may be later expanded to run in the suspend path for more scenarios. Cc: stable@vger.kernel.org # 5.16+ Suggested-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Link: https://lore.kernel.org/linux-acpi/BL1PR12MB51570F5BD05980A0DCA1F3F4E23A9@BL1PR12MB5157.namprd12.prod.outlook.com/T/#mee35f39c41a04b624700ab2621c795367f19c90e Fixes: 8d89835b ("PM: suspend: Do not pause cpuidle in the suspend-to-idle path") Fixes: 23f62d7a ("PM: sleep: Pause cpuidle later and resume it earlier during system transitions") Fixes: 59348401 ("platform/x86: amd-pmc: Add special handling for timer based S0i3 wakeup" Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Mario Limonciello <mario.limonciello@amd.com> Link: https://lore.kernel.org/r/20220223175237.6209-1-mario.limonciello@amd.com Reviewed-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
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