The acpi video driver attempts to explicitly create a sysfs link between
the acpi device and the associated PCI device. However, we're now also
doing this from the backlight core, which means that we get a backtrace
caused by a duplicate file. Remove the code and leave it up to the
backlight core.
Reported-by: Jeff Chua <jeff.chua.linux@gmail.com>
Signed-off-by: Matthew Garrett <mjg@redhat.com>
Acked-by: Rafael J. Wysocki <rjw@sisk.pl>
Tested-by: Alessandro Suardi <alessandro.suardi@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6:
PCI: Disable ASPM when _OSC control is not granted for PCIe services
PCI: Changing ASPM policy, via /sys, to POWERSAVE could cause NMIs
PCI: PCIe links may not get configured for ASPM under POWERSAVE mode
PCI/ACPI: Report ASPM support to BIOS if not disabled from command line
Make /sys output from acpi_pad more readable.
Before the fix:
# cat idlecpus idlepct rrtime
00000000510
After the fix:
# cat idlecpus idlepct rrtime
00000000
5
10
Signed-off-by: Naga Chumbalkar <nagananda.chumbalkar@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
The reset register was only introduced with version 2 of the FADT, so we
should check that the FADT revision before trusting its contents.
Signed-off-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Windows ignores the bit_offset and bit_width, despite the spec requiring
that they be validated. Drop the checks so that we match this behaviour.
Windows also goes straight for the keyboard controller if the ACPI reboot
fails, so we shouldn't sleep if we're still alive.
Signed-off-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Section 4.7.3.6 of the ACPI specification requires that the register width
of the reset vector be 8 bits. Windows simply hardcodes the access to be
a byte and ignores the width provided in the FADT, so make sure that we
do the same.
Signed-off-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Commit da8aeb92 re-poked the battery on resume, but Linus reports that
it broke his eee and partially reverted it in b23fffd7. Unfortunately
this also results in my x201s giving crack values until the sysfs files
are poked again. In the revert message, it was suggested that we poke it
from a PM notifier, so let's do that.
With this in place, I haven't noticed the units going nutty on my
gnome-power-manager across a dozen suspends or so...
Signed-off-by: Kyle McMartin <kyle@redhat.com>
Acked-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Len Brown <len.brown@intel.com>
The AER error information printing support is implemented in
drivers/pci/pcie/aer/aer_print.c. So some string constants, functions
and macros definitions can be re-used without being exported.
The original PCIe AER error information printing function is not
re-used directly because the overall format is quite different. And
changing the original printing format may make some original users'
scripts broken.
Signed-off-by: Huang Ying <ying.huang@intel.com>
CC: Jesse Barnes <jbarnes@virtuousgeek.org>
CC: Zhang Yanmin <yanmin.zhang@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
APEI ERST firmware interface and implementation has no multiple users
in mind. For example, if there is four records in storage with ID: 1,
2, 3 and 4, if two ERST readers enumerate the records via
GET_NEXT_RECORD_ID as follow,
reader 1 reader 2
1
2
3
4
-1
-1
where -1 signals there is no more record ID.
Reader 1 has no chance to check record 2 and 4, while reader 2 has no
chance to check record 1 and 3. And any other GET_NEXT_RECORD_ID will
return -1, that is, other readers will has no chance to check any
record even they are not cleared by anyone.
This makes raw GET_NEXT_RECORD_ID not suitable for used by multiple
users.
To solve the issue, an in-memory ERST record ID cache is designed and
implemented. When enumerating record ID, the ID returned by
GET_NEXT_RECORD_ID is added into cache in addition to be returned to
caller. So other readers can check the cache to get all record ID
available.
Signed-off-by: Huang Ying <ying.huang@intel.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
v3 -> v2: Added text to describe the problem
v2 -> v1: Split this patch from v1
v1 : Part of: http://marc.info/?l=linux-pci&m=130042212003242&w=2
Disable ASPM when no _OSC control for PCIe services is granted
by the BIOS. This is to protect systems with a buggy BIOS that
did not set the ACPI FADT "ASPM Controls" bit even though the
underlying HW can't do ASPM.
To turn "on" ASPM the minimum the BIOS needs to do:
1. Clear the ACPI FADT "ASPM Controls" bit.
2. Support _OSC appropriately
There is no _OSC Control bit for ASPM. However, we expect the BIOS to
support _OSC for a Root Bridge that originates a PCIe hierarchy. If this
is not the case - we are better off not enabling ASPM on that server.
Commit 852972acff (ACPI: Disable ASPM if the
Platform won't provide _OSC control for PCIe) describes the above scenario.
To quote verbatim from there:
[The PCI SIG documentation for the _OSC OS/firmware handshaking interface
states:
"If the _OSC control method is absent from the scope of a host bridge
device, then the operating system must not enable or attempt to use any
features defined in this section for the hierarchy originated by the host
bridge."
The obvious interpretation of this is that the OS should not attempt to use
PCIe hotplug, PME or AER - however, the specification also notes that an
_OSC method is *required* for PCIe hierarchies, and experimental validation
with An Alternative OS indicates that it doesn't use any PCIe functionality
if the _OSC method is missing. That arguably means we shouldn't be using
MSI or extended config space, but right now our problems seem to be limited
to vendors being surprised when ASPM gets enabled on machines when other
OSs refuse to do so. So, for now, let's just disable ASPM if the _OSC
method doesn't exist or refuses to hand over PCIe capability control.]
Signed-off-by: Naga Chumbalkar <nagananda.chumbalkar@hp.com>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
We need to distinguish the situation in which ASPM support is
disabled from the command line or through .config from the situation
in which it is disabled, because the hardware or BIOS can't handle
it. In the former case we should not report ASPM support to the BIOS
through ACPI _OSC, but in the latter case we should do that.
Introduce pcie_aspm_support_enabled() that can be used by
acpi_pci_root_add() to determine whether or not it should report ASPM
support to the BIOS through _OSC.
Cc: stable@kernel.org
References: https://bugzilla.kernel.org/show_bug.cgi?id=29722
References: https://bugzilla.kernel.org/show_bug.cgi?id=20232
Reported-and-tested-by: Ortwin Glück <odi@odi.ch>
Reviewed-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Tested-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
ACPI uses a sysdev class and a sysdev for executing
irqrouter_resume() before turning on interrupts on the boot CPU.
However, since irqrouter_resume() ignores its argument, the entire
mechanism may be replaced with a struct syscore_ops object which
is considerably simpler.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Len Brown <len.brown@intel.com>
The ACPI EC driver defines a sysdev class, but it doesn't use it, so
it can be removed.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Len Brown <len.brown@intel.com>