lkml.org 
[lkml]   [2022]   [Apr]   [7]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH v1] PCI: PM: Power up all devices during runtime resume
On Wed, Apr 06, 2022 at 09:00:52PM +0200, Rafael J. Wysocki wrote:
> From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
>
> Currently, endpoint devices may not be powered up entirely during
> runtime resume that follows a D3hot -> D0 transition of the parent
> bridge.
>
> Namely, even if the power state of an endpoint device, as indicated
> by its PCI_PM_CTRL register, is D0 after powering up its parent
> bridge, it may be still necessary to bring its ACPI companion into
> D0 and that should be done before accessing it. However, the current
> code assumes that reading the PCI_PM_CTRL register is sufficient to
> establish the endpoint device's power state, which may lead to
> problems.
>
> Address that by forcing a power-up of all PCI devices, including the
> platform firmware part of it, during runtime resume.
>
> Link: https://lore.kernel.org/linux-pm/11967527.O9o76ZdvQC@kreacher
> Fixes: 5775b843a619 ("PCI: Restore config space on runtime resume despite being unbound")
> Reported-by: Abhishek Sahu <abhsahu@nvidia.com>
> Tested-by: Abhishek Sahu <abhsahu@nvidia.com>
> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>

\
 
 \ /
  Last update: 2022-04-07 17:31    [W:0.050 / U:0.384 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site