Add support for ASPM L1 substates. For details about L1 substates, see the
PCIe r3.1 spec, which includes the ECN below in secs 5.5 and 7.33.
Add macros for the 4 new L1 substates, and add a new ASPM "POWER_SUPERSAVE"
policy that can be used to enable L1 substates on a system if desired. The
new policy is in a sense, a superset of the existing POWERSAVE policy. The
4 policies are now:
DEFAULT: Reads and uses whatever ASPM states BIOS enabled
PERFORMANCE: Everything except L0 disabled.
POWERSAVE: L0s and L1 enabled (but not L1 substates)
POWER_SUPERSAVE: L0s + L1 + L1 substates also enabled
[bhelgaas: add PCIe r3.1 spec reference]
Link: https://pcisig.com/sites/default/files/specification_documents/ECN_L1_PM_Substates_with_CLKREQ_31_May_2013_Rev10a.pdf
Signed-off-by: Rajat Jain <rajatja@google.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Add Precision Time Measurement (PTM) support (see PCIe r3.1, sec 6.22).
Enable PTM on PTM Root devices and switch ports. This does not enable PTM
on endpoints.
There currently are no PTM-capable devices on the market, but it is
expected to be supported by the Intel Apollo Lake platform.
[bhelgaas: complete rework]
Signed-off-by: Jonathan Yong <jonathan.yong@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Change the Downstream Port Containment config type from tristate to bool.
The driver doesn't automatically load based on any rules, so it needs to be
built-in in order to bind to devices it needs to drive.
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Add driver for the PCI Express Downstream Port Containment extended
capability. DPC is an optional capability to contain uncorrectable errors
below a port.
For more information on DPC, please see PCI Express Base Specification
Revision 4, section 7.31, or view the PCI-SIG DPC ECN here:
https://pcisig.com/sites/default/files/specification_documents/ECN_DPC_2012-02-09_finalized.pdf
When a DPC event is triggered, the hardware disables downstream links, so
the DPC driver schedules removal for all devices below this port. This may
happen concurrently with a PCIe hotplug driver if enabled. When all
downstream devices are removed and the link state transitions to disabled,
the DPC driver clears the DPC status and interrupt bits so the link may
retrain for a newly connected device.
[bhelgaas: clear (not set) DPC_CTL bits on remove, whitespace cleanup]
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: Lukas Wunner <lukas@wunner.de>
Clean up style issues in drivers/pci/pcie/Kconfig, in particular all
indentation is now done using tabs, not spaces, and the definition of
PCIEASPM_DEBUG is now separated from the definition of PCIEASPM with a
newline.
Signed-off-by: Andreas Ziegler <andreas.ziegler@fau.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
After commit b2b49ccbdd (PM: Kconfig: Set PM_RUNTIME if PM_SLEEP is
selected) PM_RUNTIME is always set if PM is set, so quite a few
depend on CONFIG_PM.
Replace CONFIG_PM_RUNTIME with CONFIG_PM in the PCI core code.
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Convert pciehp to be builtin only, with no module option.
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
The previous option title "PCI Express support" is confusing. The name
seems to imply this option is required to get PCIe support, which is not
true.
Fix it to "PCI Express Port Bus support" which is more accurate.
Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
PCIe PME doesn't depend on ACPI, so remove the #includes and
Kconfig dependency.
Based-on-patch-by: Andrew Murray <Andrew.Murray@arm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The CONFIG_EXPERIMENTAL config item has not carried much meaning for a
while now and is almost always enabled by default. As agreed during the
Linux kernel summit, remove it from any "depends on" lines in Kconfigs.
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Distributions may wish to provide different defaults for PCIE ASPM
depending on their target audience. Provide a configuration option for
choosing the default policy.
Signed-off-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
The meaning of CONFIG_EMBEDDED has long since been obsoleted; the option
is used to configure any non-standard kernel with a much larger scope than
only small devices.
This patch renames the option to CONFIG_EXPERT in init/Kconfig and fixes
references to the option throughout the kernel. A new CONFIG_EMBEDDED
option is added that automatically selects CONFIG_EXPERT when enabled and
can be used in the future to isolate options that should only be
considered for embedded systems (RISC architectures, SLOB, etc).
Calling the option "EXPERT" more accurately represents its intention: only
expert users who understand the impact of the configuration changes they
are making should enable it.
Reviewed-by: Ingo Molnar <mingo@elte.hu>
Acked-by: David Woodhouse <david.woodhouse@intel.com>
Signed-off-by: David Rientjes <rientjes@google.com>
Cc: Greg KH <gregkh@suse.de>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Robin Holt <holt@sgi.com>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The CONFIG_PCIEASPM option is confusing and potentially dangerous. ASPM is
a hardware mediated feature rather than one under direct OS control, and
even if the config option is disabled the system firmware may have turned
on ASPM on various bits of hardware. This can cause problems later -
various hardware that claims to support ASPM does a poor job of it and may
hang or cause other difficulties. The kernel is able to recognise this in
many cases and disable the ASPM functionality, but only if CONFIG_PCIEASPM
is enabled.
Given that in its default configuration this option will either leave the
hardware as it was originally or disable hardware functionality that may
cause problems, it should by default y. The only reason to disable it
ought to be to reduce code size, so make it dependent on CONFIG_EMBEDDED.
Signed-off-by: Matthew Garrett <mjg@redhat.com>
Cc: lrodriguez@atheros.com
Cc: maximlevitsky@gmail.com
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
PCIe native PME detection mechanism is based on interrupts generated
by root ports or event collectors every time a PCIe device sends a
PME message upstream.
Once a PME message has been sent by an endpoint device and received
by its root port (or event collector in the case of root complex
integrated endpoints), the Requester ID from the message header is
registered in the root port's Root Status register. At the same
time, the PME Status bit of the Root Status register is set to
indicate that there's a PME to handle. If PCIe PME interrupt is
enabled for the root port, it generates an interrupt once the PME
Status has been set. After receiving the interrupt, the kernel can
identify the PCIe device that generated the PME using the Requester
ID from the root port's Root Status register. [For details, see PCI
Express Base Specification, Rev. 2.0.]
Implement a driver for the PCIe PME root port service working in
accordance with the above description.
Based on a patch from Shaohua Li <shaohua.li@intel.com>.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Running 'make oldconfig' I just noticed that PCIEASPM defaults to
'y' in Kconfig even though the feature is both experimental and the
help text recommends that if you are unsure you say 'n'.
It seems to me that this really should default to 'n', not 'y' at the
moment.
The following patch makes that change. Please consider applying.
Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
PCI Express ASPM defines a protocol for PCI Express components in the D0
state to reduce Link power by placing their Links into a low power state
and instructing the other end of the Link to do likewise. This
capability allows hardware-autonomous, dynamic Link power reduction
beyond what is achievable by software-only controlled power management.
However, The device should be configured by software appropriately.
Enabling ASPM will save power, but will introduce device latency.
This patch adds ASPM support in Linux. It introduces a global policy for
ASPM, a sysfs file /sys/module/pcie_aspm/parameters/policy can control
it. The interface can be used as a boot option too. Currently we have
below setting:
-default, BIOS default setting
-powersave, highest power saving mode, enable all available ASPM
state and clock power management
-performance, highest performance, disable ASPM and clock power
management
By default, the 'default' policy is used currently.
In my test, power difference between powersave mode and performance mode
is about 1.3w in a system with 3 PCIE links.
Note: some devices might not work well with aspm, either because chipset
issue or device issue. The patch provide API (pci_disable_link_state),
driver can disable ASPM for specific device.
Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This reverts commit 6c723d5bd8.
It caused build errors on non-x86 platforms, config file confusion, and
even some boot errors on some x86-64 boxes. All around, not quite ready
for prime-time :(
Cc: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
PCI Express ASPM defines a protocol for PCI Express components in the D0
state to reduce Link power by placing their Links into a low power state
and instructing the other end of the Link to do likewise. This
capability allows hardware-autonomous, dynamic Link power reduction
beyond what is achievable by software-only controlled power management.
However, The device should be configured by software appropriately.
Enabling ASPM will save power, but will introduce device latency.
This patch adds ASPM support in Linux. It introduces a global policy for
ASPM, a sysfs file /sys/module/pcie_aspm/parameters/policy can control
it. The interface can be used as a boot option too. Currently we have
below setting:
-default, BIOS default setting
-powersave, highest power saving mode, enable all available ASPM
state
and clock power management
-performance, highest performance, disable ASPM and clock power
management
By default, the 'default' policy is used currently.
In my test, power difference between powersave mode and performance mode
is about 1.3w in a system with 3 PCIE links.
Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Remove unnecessary CONFIG_HOTPLUG_PCI_PCIE_EVENT_MODE.
The CONFIG_HOTPLUG_PCI_PCIE_POLL_EVENT_MODE option is not needed
because polling mechanism can be enabled through 'pciehp_poll_mode'
module option.
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Patch 3 implements the core part of PCI-Express AER and aerdrv
port service driver.
When a root port service device is probed, the aerdrv will call
request_irq to register irq handler for AER error interrupt.
When a device sends an PCI-Express error message to the root port,
the root port will trigger an interrupt, by either MSI or IO-APIC,
then kernel would run the irq handler. The handler collects root
error status register and schedules a work. The work will call
the core part to process the error based on its type
(Correctable/non-fatal/fatal).
As for Correctable errors, the patch chooses to just clear the correctable
error status register of the device.
As for the non-fatal error, the patch follows generic PCI error handler
rules to call the error callback functions of the endpoint's driver. If
the device is a bridge, the patch chooses to broadcast the error to
downstream devices.
As for the fatal error, the patch resets the pci-express link and
follows generic PCI error handler rules to call the error callback
functions of the endpoint's driver. If the device is a bridge, the patch
chooses to broadcast the error to downstream devices.
Signed-off-by: Zhang Yanmin <yanmin.zhang@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
