Commit Graph

8 Commits

Author SHA1 Message Date
Keith Busch 89ee9f7680 PCI: Add device disconnected state
Add a new state to pci_dev to be set when it is unexpectedly disconnected.
The PCI driver tear down functions can observe this new device state so
they may skip operations that will fail.

The pciehp and pcie-dpc drivers are aware when the link is down, so these
set the flag when their handlers detect the device is disconnected.

Tested-by: Krishna Dhulipala <krishnad@fb.com>
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Wei Zhang <wzhang@fb.com>
2017-03-29 22:54:46 -05:00
Keith Busch abdbf4d635 PCI/DPC: Wait for Root Port busy to clear
Per PCIe r3.1, sec 6.2.10 and sec 7.13.4, on Root Ports that support "RP
Extensions for DPC",

  When the DPC Trigger Status bit is Set and the DPC RP Busy bit is Set,
  software must leave the Root Port in DPC until the DPC RP Busy bit reads
  0b.

Wait up to 1 second for the Root Port to become non-busy.

[bhelgaas: changelog, spec references]
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2017-02-10 14:36:14 -06:00
Keith Busch 87b336d003 PCI/DPC: Decode extended reasons
Decode the currently defined extended event reasons rather than just using
the generic "extended" explanation.

Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2017-02-10 14:35:02 -06:00
Paul Gortmaker 61612e6dd4 PCI: Make DPC explicitly non-modular
This code is not being built as a module by anyone:

  drivers/pci/pcie/Kconfig:config PCIE_DPC
  drivers/pci/pcie/Kconfig:  bool "PCIe Downstream Port Containment support"

Remove uses of MODULE_DESCRIPTION(), MODULE_AUTHOR(), MODULE_LICENSE(),
etc., so that when reading the driver there is no doubt it is builtin-only.
The information is preserved in comments at the top of the file.

Note that for non-modular code, module_init() translates to
device_initcall().

[bhelgaas: changelog]
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: Keith Busch <keith.busch@intel.com>
CC: Mika Westerberg <mika.westerberg@linux.intel.com>
2016-08-24 16:52:24 -05:00
Keith Busch 7e16fd6df1 PCI: Bind DPC to Root Ports as well as Downstream Ports
PCIe port type values are not flags, so OR'ing them is not correct.
Previously the result was equivalent to PCIe Downstream Ports, so we were
missing binding to DPC-capable Root Ports.

Change the type to 'any' so we can bind to both port types.  While this
will cause the code to check Upstream Ports, the driver won't claim them
since they are not DPC-capable.

Reported-by: Alexander Antonov <alexanderx.v.antonov@intel.com>
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: Mika Westerberg <mika.westerberg@linux.intel.com>
2016-07-25 12:45:19 -05:00
Mika Westerberg 14a16d57ea PCI: Fix whitespace in struct dpc_dev
Remove unnecessary spaces before tabs.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Keith Busch <keith.busch@intel.com>
2016-06-21 13:49:57 -05:00
Mika Westerberg 733f3d1339 PCI: Convert Downstream Port Containment driver to use devm_* functions
Use the device resource management (devm) interfaces so we don't need to
explicitly release resources on failure paths or when the driver is
removed.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Keith Busch <keith.busch@intel.com>
2016-06-21 12:30:42 -05:00
Keith Busch 26e5157133 PCI: Add Downstream Port Containment driver
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>
2016-05-03 10:39:24 -05:00