The spec has timing requirements when waiting for a link to become active
after a conventional reset. Implement those hard delays when waiting for
an active link so pciehp and dpc drivers don't need to duplicate this.
For devices that don't support data link layer active reporting, wait the
fixed time recommended by the PCIe spec.
Signed-off-by: Keith Busch <keith.busch@intel.com>
[bhelgaas: changelog]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Sinan Kaya <okaya@kernel.org>
We don't need to be paranoid about the topology changing while handling an
error. If the device has changed in a hotplug capable slot, we can rely on
the presence detection handling to react to a changing topology.
Restore the fatal error handling behavior that existed before merging DPC
with AER with 7e9084b367 ("PCI/AER: Handle ERR_FATAL with removal and
re-enumeration of devices").
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Sinan Kaya <okaya@kernel.org>
This patch provides DPC save and restore capabilities. This is necessary
for the driver to observe DPC events in the event the configuration space
needs to be restored after a reset.
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Sinan Kaya <okaya@kernel.org>
The PCI port driver saves the PCI state after initializing the device with
the applicable service devices. This was, however, before the service
drivers were even registered because PCI probe happens before the
device_initcall initialized those service drivers. The config space state
that the services set up were not being saved. The end result would cause
PCI devices to not react to events that the drivers think they did if the
PCI state ever needed to be restored.
Fix this by changing the service drivers from using the init calls to
having the portdrv driver calling the services directly. This will get the
state saved as desired, while making the relationship between the port
driver and the services under it more explicit in the code.
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Sinan Kaya <okaya@kernel.org>
Simplify waiting for the contained link to become inactive, removing the
indirection to a unnecessary DPC-specific handler.
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Sinan Kaya <okaya@kernel.org>
Reviewed-by: Oza Pawandeep <poza@codeaurora.org>
Remove the work struct that was being used to handle a DPC event and use a
threaded IRQ instead.
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Sinan Kaya <okaya@kernel.org>
Reviewed-by: Oza Pawandeep <poza@codeaurora.org>
A DPC enabled device suppresses ERR_(NON)FATAL messages, preventing the AER
handler from reporting error details. If the DPC trigger reason says the
downstream port detected the error, collect the AER uncorrectable status
for logging, then clear the status.
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Sinan Kaya <okaya@kernel.org>
Reviewed-by: Oza Pawandeep <poza@codeaurora.org>
We don't need to save the rp pio status across multiple contexts as all
DPC event handling occurs in a single work queue context.
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Sinan Kaya <okaya@kernel.org>
Reviewed-by: Oza Pawandeep <poza@codeaurora.org>
Move all event handling to the existing work queue, which will
make it simpler to pass event information to the handler.
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Sinan Kaya <okaya@kernel.org>
Reviewed-by: Oza Pawandeep <poza@codeaurora.org>
Now that the DPC driver clears the interrupt status before exiting the
IRQ handler, we don't need to abuse the DPC control register to know if
a shared interrupt is for a new DPC event: a DPC port can not trigger
a second interrupt until the host clears the trigger status later in the
work queue handler.
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Sinan Kaya <okaya@kernel.org>
Reviewed-by: Oza Pawandeep <poza@codeaurora.org>
Move pcie_aer_get_firmware_first() to portdrv.h, where it can be more
easily shared between AER and DPC. Then DPC no longer needs to include
aer/aerdrv.h. No functional change intended.
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Our goal is to handle ERR_FATAL errors similarly, whether they are reported
via AER or via DPC. A previous commit changed AER so it handles ERR_FATAL
by calling driver .remove() methods and resetting the Link. DPC already
does that (although the Link reset is done automatically by hardware and
happens before we call the driver .remove() methods).
Restructure the DPC code so it calls the same pcie_do_fatal_recovery()
interface used by AER. This makes it clearer that we want to use the same
path.
Implement the .reset_link() method used by pcie_do_fatal_recovery(). For
DPC, the actual reset is done automatically by hardware, so we really only
have to wait for the Link to be inactive, then release the Port from DPC.
Signed-off-by: Oza Pawandeep <poza@codeaurora.org>
[bhelgaas: changelog, DPC_FATAL is not a bitfield, can be sequential]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
PCIe ERR_NONFATAL errors mean a particular transaction is unreliable but
the Link is otherwise fully functional (PCIe r4.0, sec 6.2.2).
The AER driver handles these by logging the error details and calling
driver-supplied pci_error_handlers callbacks. It does not reset downstream
devices, does not remove them from the PCI subsystem, does not re-enumerate
them, and does not call their driver .remove() or .probe() methods.
But DPC driver previously enabled DPC on ERR_NONFATAL, so if the hardware
supports DPC, these errors caused a Link reset (performed automatically by
the hardware), followed by the DPC driver removing affected devices (which
calls their .remove() methods), bringing the Link back up, and
re-enumerating (which calls driver .probe() methods).
Disable ERR_NONFATAL DPC triggering so these errors will only be handled by
AER. This means drivers won't have to deal with different usage of their
pci_error_handlers callbacks and .probe() and .remove() methods based on
whether the platform has DPC support.
Signed-off-by: Oza Pawandeep <poza@codeaurora.org>
[bhelgaas: changelog]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Clients such as hotplug and Downstream Port Containment (DPC) both need to
wait until a link becomes active or inactive.
Add a generic pcie_wait_link_active() interface and use it instead of
duplicating the code.
Signed-off-by: Oza Pawandeep <poza@codeaurora.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Keith Busch <keith.busch@intel.com>
The generic IRQ handling code ensures that an interrupt handler runs with
its interrupt masked or disabled. If the interrupt is level-triggered, the
interrupt handler must tell its device to stop asserting the interrupt
before returning. If it doesn't, we will immediately take the interrupt
again when the handler returns and the generic code unmasks the interrupt.
The driver doesn't know whether its interrupt is edge- or level-triggered,
so it must clear its interrupt source directly in its interrupt handler.
Previously we cleared the DPC interrupt status in the bottom half, i.e., in
deferred work, which can cause an interrupt storm if the DPC interrupt
happens to be level-triggered, e.g., if we're using INTx instead of MSI.
Clear the DPC interrupt status bit in the interrupt handler, not in the
deferred work.
Signed-off-by: Oza Pawandeep <poza@codeaurora.org>
[bhelgaas: changelog]
Signed-off-by: Bjorn Helgaas <helgaas@kernel.org>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Rename pcie-dpc.c to dpc.c. The path "drivers/pci/pcie/pcie-dpc.c" has
more occurrences of "pci" than necessary.
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-03-31 17:48:57 -05:00
Renamed from drivers/pci/pcie/pcie-dpc.c (Browse further)
