Commit Graph

481 Commits

Author SHA1 Message Date
Bjorn Helgaas a1aed6b34f Merge branch 'pci/devtree-create'
- Add device_add_of_node() to set dev->of_node and dev->fwnode only if they
  haven't been set already (Herve Codina)

- Allow of_pci_set_address() to set the DT address property for root bus
  nodes, where there is no PCI bridge to supply the PCI bus/device/function
  part of the property (Herve Codina)

- Create DT nodes for PCI host bridges to enable loading device tree
  overlays to create platform devices for PCI devices that have several
  features that require multiple drivers (Herve Codina)

* pci/devtree-create:
  PCI: of: Create device tree PCI host bridge node
  PCI: of_property: Constify parameter in of_pci_get_addr_flags()
  PCI: of_property: Add support for NULL pdev in of_pci_set_address()
  PCI: of: Use device_{add,remove}_of_node() to attach of_node to existing device
  driver core: Introduce device_{add,remove}_of_node()
2025-03-27 13:14:45 -05:00
Bjorn Helgaas 38d42a6612 Merge branch 'pci/resource'
- Use pci_resource_n() to simplify BAR/window resource lookup (Ilpo
  Järvinen)

- Fix typo that repeatedly distributed resources to a bridge instead of
  iterating over subordinate bridges, which resulted in too little space to
  assign some BARs (Kai-Heng Feng)

- Relax bridge window tail sizing for optional resources, e.g., IOV BARs,
  to avoid failures when removing and re-adding devices (Ilpo Järvinen)

- Fix a double counting error for I/O resources, as we previously did for
  memory resources (Ilpo Järvinen)

- Use resource_set_{range,size}() helpers in more places (Ilpo Järvinen)

- Add pci_resource_is_iov() to identify IOV resources (Ilpo Järvinen)

- Add pci_resource_num() to look up the BAR number from the resource
  pointer (Ilpo Järvinen)

- Add restore_dev_resource() to simplify code that resources saved device
  resources (Ilpo Järvinen)

- Allow drivers to enable devices even if we haven't assigned optional IOV
  resources to them (Ilpo Järvinen)

- Improve debug output during resource reallocation (Ilpo Järvinen)

- Rework handling of optional resources (IOV BARs, ROMs) to reduce failures
  if we can't allocate them (Ilpo Järvinen)

- Move declarations of pci_rescan_bus_bridge_resize(),
  pci_reassign_bridge_resources(), and CardBus-related sizes from
  include/linux/pci.h to drivers/pci/pci.h since they're not used outside
  the PCI core (Ilpo Järvinen)

- Make pci_setup_bridge() static (Ilpo Järvinen)

- Fix a NULL dereference in the SR-IOV VF creation error path (Shay Drory)

- Fix s390 mmio_read/write syscalls, which didn't cause page faults in some
  cases, which broke vfio-pci lazy mapping on first access (Niklas
  Schnelle)

- Add pdev->non_mappable_bars to replace CONFIG_VFIO_PCI_MMAP, which was
  disabled only for s390 (Niklas Schnelle)

- Support mmap of PCI resources on s390 except for ISM devices (Niklas
  Schnelle)

* pci/resource:
  s390/pci: Support mmap() of PCI resources except for ISM devices
  s390/pci: Introduce pdev->non_mappable_bars and replace VFIO_PCI_MMAP
  s390/pci: Fix s390_mmio_read/write syscall page fault handling
  PCI: Fix NULL dereference in SR-IOV VF creation error path
  PCI: Move cardbus IO size declarations into pci/pci.h
  PCI: Make pci_setup_bridge() static
  PCI: Move resource reassignment func declarations into pci/pci.h
  PCI: Move pci_rescan_bus_bridge_resize() declaration to pci/pci.h
  PCI: Fix BAR resizing when VF BARs are assigned
  PCI: Do not claim to release resource falsely
  PCI: Increase Resizable BAR support from 512 GB to 128 TB
  PCI: Rework optional resource handling
  PCI: Perform reset_resource() and build fail list in sync
  PCI: Use res->parent to check if resource is assigned
  PCI: Add debug print when releasing resources before retry
  PCI: Indicate optional resource assignment failures
  PCI: Always have realloc_head in __assign_resources_sorted()
  PCI: Extend enable to check for any optional resource
  PCI: Add restore_dev_resource()
  PCI: Remove incorrect comment from pci_reassign_resource()
  PCI: Consolidate assignment loop next round preparation
  PCI: Rename retval to ret
  PCI: Use while loop and break instead of gotos
  PCI: Refactor pdev_sort_resources() & __dev_sort_resources()
  PCI: Converge return paths in __assign_resources_sorted()
  PCI: Add dev & res local variables to resource assignment funcs
  PCI: Add pci_resource_num() helper
  PCI: Check resource_size() separately
  PCI: Add pci_resource_is_iov() to identify IOV resources
  PCI: Use resource_set_{range,size}() helpers
  PCI: Use SZ_* instead of literals in setup-bus.c
  PCI: Fix old_size lower bound in calculate_iosize() too
  PCI: Allow relaxed bridge window tail sizing for optional resources
  PCI: Simplify size1 assignment logic
  PCI: Use min_align, not unrelated add_align, for size0
  PCI: Remove add_align overwrite unrelated to size0
  PCI: Use downstream bridges for distributing resources
  PCI: Cleanup dev->resource + resno to use pci_resource_n()
2025-03-27 13:14:45 -05:00
Bjorn Helgaas e9e224dadd Merge branch 'pci/enumeration'
- Enable Configuration RRS SV early instead of during child bus scanning
  (Bjorn Helgaas)

- Cache offset of Resizable BAR capability to avoid redundant searches for
  it (Bjorn Helgaas)

- Fix reference leaks in pci_register_host_bridge() and
  pci_alloc_child_bus() (Ma Ke)

- Drop put_device() in pci_register_host_bridge() left over from converting
  device_register() to device_add() (Dan Carpenter)

* pci/enumeration:
  PCI: Remove stray put_device() in pci_register_host_bridge()
  PCI: Fix reference leak in pci_alloc_child_bus()
  PCI: Fix reference leak in pci_register_host_bridge()
  PCI: Cache offset of Resizable BAR capability
  PCI: Enable Configuration RRS SV early
2025-03-27 13:14:43 -05:00
Bjorn Helgaas 651aa9052c Merge branch 'pci/doe'
- Rename DOE 'protocol' to 'feature' to follow spec terminology (Alistair
  Francis)

- Expose supported DOE features via sysfs (Alistair Francis)

- Allow DOE support to be enabled even if CXL isn't enabled (Alistair
  Francis)

* pci/doe:
  PCI/DOE: Allow enabling DOE without CXL
  PCI/DOE: Expose DOE features via sysfs
  PCI/DOE: Rename Discovery Response Data Object Contents to type
  PCI/DOE: Rename DOE protocol to feature
2025-03-27 13:14:43 -05:00
Bjorn Helgaas 67b9f18202 Merge branch 'pci/devres'
- Enlarge the devres table[] to accommodate bridge windows, ROM, IOV BARs,
  etc (Philipp Stanner)

- Validate BAR index in devres interfaces (Philipp Stanner)

* pci/devres:
  PCI: Check BAR index for validity
  PCI: Fix wrong length of devres array
2025-03-27 13:14:43 -05:00
Alistair Francis 2311ab1820 PCI/DOE: Expose DOE features via sysfs
PCIe r6.0 added support for Data Object Exchange (DOE).  When DOE is
supported, the DOE Discovery Feature must be implemented per PCIe r6.1, sec
6.30.1.1. DOE allows a requester to obtain information about the other DOE
features supported by the device.

The kernel already queries the DOE features supported and caches the
values.  Expose the values in sysfs to allow user space to determine which
DOE features are supported by the PCIe device.

By exposing the information to userspace, tools like lspci can relay the
information to users. By listing all of the supported features we can allow
userspace to parse the list, which might include vendor specific features
as well as yet to be supported features.

As the DOE Discovery feature must always be supported we treat it as a
special named attribute case. This allows the usual PCI attribute_group
handling to correctly create the doe_features directory when registering
pci_doe_sysfs_group (otherwise it doesn't and sysfs_add_file_to_group()
will seg fault).

After this patch is supported you can see something like this when
attaching a DOE device:

  $ ls /sys/devices/pci0000:00/0000:00:02.0//doe*
  0001:01        0001:02        doe_discovery

Link: https://lore.kernel.org/r/20250306075211.1855177-3-alistair@alistair23.me
Signed-off-by: Alistair Francis <alistair@alistair23.me>
[bhelgaas: drop pci_doe_sysfs_init() stub return, make
DEVICE_ATTR_RO(doe_discovery) static]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2025-03-21 16:36:01 -05:00
Ilpo Järvinen cc7a371b0b PCI: Move cardbus IO size declarations into pci/pci.h
For some reason, cardbus related io/mem size declarations are in
linux/pci.h, whereas non-cardbus sizes are already in pci/pci.h.
Move all them into one place in pci/pci.h.

Link: https://lore.kernel.org/r/20250311174701.3586-4-ilpo.jarvinen@linux.intel.com
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2025-03-20 16:44:26 -05:00
Ilpo Järvinen 7d4bcc0f26 PCI: Move resource reassignment func declarations into pci/pci.h
Neither pci_reassign_bridge_resources() nor pci_reassign_resource() is used
outside of the PCI subsystem. They seem to be naturally static functions
but since resource fitting/assignment is split between setup-bus.c and
setup-res.c, they fall into different sides of the divide and need to be
declared.

Move the declarations of pci_reassign_bridge_resources() and
pci_reassign_resource() into pci/pci.h to keep them internal to PCI
subsystem.

Link: https://lore.kernel.org/r/20250311174701.3586-2-ilpo.jarvinen@linux.intel.com
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2025-03-20 16:44:25 -05:00
Ilpo Järvinen 95c4e6d42c PCI: Move pci_rescan_bus_bridge_resize() declaration to pci/pci.h
pci_rescan_bus_bridge_resize() is only used by code inside PCI subsystem.
The comment also falsely advertises it to be for hotplug drivers, yet the
only caller is from sysfs store function. Move the function declaration
into pci/pci.h.

Link: https://lore.kernel.org/r/20250311174701.3586-1-ilpo.jarvinen@linux.intel.com
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2025-03-20 16:44:25 -05:00
Philipp Stanner b1a7f99967 PCI: Check BAR index for validity
Many functions in PCI use accessor macros such as pci_resource_len(),
which take a BAR index. That index, however, is never checked for
validity, potentially resulting in undefined behavior by overflowing the
array pci_dev.resource in the macro pci_resource_n().

Since many users of those macros directly assign the accessed value to
an unsigned integer, the macros cannot be changed easily anymore to
return -EINVAL for invalid indexes. Consequently, the problem has to be
mitigated in higher layers.

Add pci_bar_index_valid(). Use it where appropriate.

Link: https://lore.kernel.org/r/20250312080634.13731-4-phasta@kernel.org
Closes: https://lore.kernel.org/all/adb53b1f-29e1-3d14-0e61-351fd2d3ff0d@linux.intel.com/
Reported-by: Bingbu Cao <bingbu.cao@linux.intel.com>
Signed-off-by: Philipp Stanner <phasta@kernel.org>
[kwilczynski: correct if-statement condition the pci_bar_index_is_valid()
helper function uses, tidy up code comments]
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
[bhelgaas: fix typo]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2025-03-14 10:35:12 -05:00
Bjorn Helgaas a7eb9124d9 PCI: Cache offset of Resizable BAR capability
Previously most resizable BAR interfaces (pci_rebar_get_possible_sizes(),
pci_rebar_set_size(), etc) as well as pci_restore_state() searched config
space for a Resizable BAR capability.  Most devices don't have such a
capability, so this is wasted effort, especially for pci_restore_state().

Search for a Resizable BAR capability once at enumeration-time and cache
the offset so we don't have to search every time we need it.  No functional
change intended.

Link: https://lore.kernel.org/r/20250215000301.175097-3-helgaas@kernel.org
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
2025-03-10 13:41:47 -05:00
Herve Codina 1f34072441 PCI: of: Create device tree PCI host bridge node
PCI devices device tree nodes can be already created. This was introduced
by commit 407d1a5192 ("PCI: Create device tree node for bridge").

In order to have device tree nodes related to PCI devices attached on their
PCI root bus (the PCI bus handled by the PCI host bridge), a PCI root bus
device tree node is needed. This root bus node will be used as the parent
node of the first level devices scanned on the bus. On device tree based
systems, this PCI root bus device tree node is set to the node of the
related PCI host bridge. The PCI host bridge node is available in the
device tree used to describe the hardware passed at boot.

On non device tree based system (such as ACPI), a device tree node for the
PCI host bridge or for the root bus does not exist. Indeed, the PCI host
bridge is not described in a device tree used at boot simply because no
device tree is passed at boot.

The device tree PCI host bridge node creation needs to be done at runtime.
This is done in the same way as for the creation of the PCI device nodes.
I.e. node and properties are created based on computed information done by
the PCI core. Also, as is done on device tree based systems, this PCI host
bridge node is used for the PCI root bus.

With this done, hardware available in a PCI device that doesn't follow the
PCI model consisting in one PCI function handled by one driver can be
described by a device tree overlay loaded by the PCI device driver on non
device tree based systems. Those PCI devices provide a single PCI function
that includes several functionalities that require different drivers. The
device tree overlay describes the internal devices and their relationships.
It allows to load drivers needed by those different devices in order to
have functionalities handled.

Link: https://lore.kernel.org/r/20250224141356.36325-6-herve.codina@bootlin.com
Signed-off-by: Herve Codina <herve.codina@bootlin.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rob Herring (Arm) <robh@kernel.org>
2025-02-28 15:13:51 -06:00
Ilpo Järvinen 7e077e6707 PCI/ERR: Handle TLP Log in Flit mode
Flit mode introduced in PCIe r6.0 alters how the TLP Header Log is
presented through AER and DPC Capability registers. The TLP Prefix Log
Register is not present with Flit mode, and the register becomes an
extension of the TLP Header Log (PCIe r6.1 secs 7.8.4.12 & 7.9.14.13).

Adapt pcie_read_tlp_log() and struct pcie_tlp_log to read and store the
extended TLP Header Log when the Link is in Flit mode. As the Prefix Log
and Extended TLP Header are not present at the same time, a C union can be
used.

Determining whether the error occurred while the Link was in Flit mode is a
bit complicated. In case of AER, the Advanced Error Capabilities and
Control Register directly tells whether the error was logged in Flit mode
or not (PCIe r6.1 sec 7.8.4.7). The DPC Capability (PCIe r6.1 sec 7.9.14),
unfortunately, does not contain the same information.

Unlike AER, the DPC Capability does not provide a way to discern whether
the error was logged in Flit mode (this is confirmed by PCI WG to be an
oversight in the spec). DPC will bring the Link down immediately following
an error, which makes it impossible to acquire the Flit Mode Status
directly from the Link Status 2 register because Flit Mode Status is only
set in certain Link states (PCIe r6.1 sec 7.5.3.20). As a workaround, use
the flit_mode value stored into the struct pci_bus.

Link: https://lore.kernel.org/r/20250207161836.2755-3-ilpo.jarvinen@linux.intel.com
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2025-02-21 17:31:45 -06:00
Ilpo Järvinen 79c731e20d PCI: Track Flit Mode Status & print it with link status
PCIe r6.0 added Flit mode, which mainly alters HW behavior, but there are
some OS visible changes. The OS visible changes include differences in the
layout of some capabilities and interpretation of the TLP headers (in
diagnostics situations).

To be able to determine which mode the PCIe Link is using, store the Flit
Mode Status (PCIe r6.1 sec 7.5.3.20) information in addition to the Link
speed into struct pci_bus in pcie_update_link_speed().

Link: https://lore.kernel.org/r/20250207161836.2755-2-ilpo.jarvinen@linux.intel.com
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
[bhelgaas: use unsigned int:1 instead of bool, update flit_mode setting]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2025-02-21 17:31:35 -06:00
Ilpo Järvinen 9caf4ea2fd PCI: Extend enable to check for any optional resource
pci_enable_resources() checks if device's io and mem resources are all
assigned and disallows enable if any resource failed to assign (*) but
makes an exception for the case of disabled extension ROM. There are other
optional resources, however.

Add pci_resource_is_optional() and use it instead of
pci_resource_is_disabled_rom() to cover also IOV resources that are also
optional as per pbus_size_mem().

As there will be more users of pci_resource_is_optional() inside
setup-bus.c in changes coming up after this one, the function is placed
there.

(*) In practice, resource fitting code calls reset_resource() for any
resource it fails to assign which clears resource's ->flags causing
pci_enable_resources() to never detect failed resource assignments.
This seems undesirable internal logic inconsistency, effectively
reset_resource() prevents pci_enable_resources() from functioning as
intended. This is one step of many that will be needed towards removing
reset_resource().

Link: https://lore.kernel.org/r/20241216175632.4175-20-ilpo.jarvinen@linux.intel.com
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Tested-by: Xiaochun Lee <lixc17@lenovo.com>
2025-02-18 15:40:54 -06:00
Ilpo Järvinen e4728eed24 PCI: Add pci_resource_num() helper
A few places in PCI code, mainly in setup-bus.c, need to reverse lookup the
index of a resource in pci_dev's resource array. Create pci_resource_num()
helper to avoid repeating the pointer arithmetic trick used to calculate
the index.

Link: https://lore.kernel.org/r/20241216175632.4175-11-ilpo.jarvinen@linux.intel.com
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Tested-by: Xiaochun Lee <lixc17@lenovo.com>
2025-02-18 15:40:53 -06:00
Michał Winiarski cbd384389e PCI: Add pci_resource_is_iov() to identify IOV resources
There are multiple places where special handling is required for IOV
resources.

Extract the identification of IOV resources to pci_resource_is_iov() and
drop a few ifdefs.

Link: https://lore.kernel.org/r/20241216175632.4175-9-ilpo.jarvinen@linux.intel.com
Signed-off-by: Michał Winiarski <michal.winiarski@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Tested-by: Xiaochun Lee <lixc17@lenovo.com>
2025-02-18 15:40:52 -06:00
Bjorn Helgaas 60b5cd4f82 Merge branch 'pci/pci-sysfs'
- Move reset related sysfs code from pci.c to pci-sysfs.c where other
  similar code lives (Ilpo Järvinen)

- Simplify reset_method_store() memory management by using __free() instead
  of explicit kfree() cleanup (Ilpo Järvinen)

- Drop unnecessary zero initializer (Ilpo Järvinen)

* pci/pci-sysfs:
  PCI/sysfs: Remove unnecessary zero in initializer
  PCI/sysfs: Use __free() in reset_method_store()
  PCI/sysfs: Move reset related sysfs code to correct file
2025-01-23 13:04:51 -06:00
Bjorn Helgaas ccbd884f9e Merge branch 'pci/of'
- Unexport of_pci_parse_bus_range() since it's only used in of.c (Bjorn
  Helgaas)

- Drop 'No bus range found' message so we don't complain when DTs don't
  specify the default 'bus-range = <0x00 0xff>' (Bjorn Helgaas)

- Simplify devm_of_pci_get_host_bridge_resources() interface by dropping
  parameters that are always the same default values (Bjorn Helgaas)

- Update comment reference to of_pci_get_host_bridge_resources(), which no
  longer exists (Bjorn Helgaas)

- Rename the drivers/pci/of_property.c struct of_pci_range to
  of_pci_range_entry to avoid confusion with the global of_pci_range in
  include/linux/of_address.h (Bjorn Helgaas)

* pci/of:
  PCI: of_property: Rename struct of_pci_range to of_pci_range_entry
  sparc/PCI: Update reference to devm_of_pci_get_host_bridge_resources()
  PCI: of: Simplify devm_of_pci_get_host_bridge_resources() interface
  PCI: of: Drop 'No bus range found' message
  PCI: Unexport of_pci_parse_bus_range()
2025-01-23 13:04:51 -06:00
Bjorn Helgaas f4a09274c5 Merge branch 'pci/err'
- Unexport pcie_read_tlp_log() to encourage drivers to use PCI core logging
  rather than building their own (Ilpo Järvinen)

- Move TLP Log handling to its own file (Ilpo Järvinen)

- Add #defines for TLP Header/Prefix log sizes (Ilpo Järvinen)

- Store number of supported End-End TLP Prefixes always so we can read the
  correct number of DWORDs from the TLP Prefix Log (Ilpo Järvinen)

- Read TLP Prefixes in addition to the Header Log in pcie_read_tlp_log()
  (Ilpo Järvinen)

- Add pcie_print_tlp_log() to consolidate printing of TLP Header and Prefix
  Log (Ilpo Järvinen)

* pci/err:
  PCI: Add pcie_print_tlp_log() to print TLP Header and Prefix Log
  PCI: Add TLP Prefix reading to pcie_read_tlp_log()
  PCI: Store number of supported End-End TLP Prefixes
  PCI: Use unsigned int i in pcie_read_tlp_log()
  PCI: Use same names in pcie_read_tlp_log() prototype and definition
  PCI: Add defines for TLP Header/Prefix log sizes
  PCI: Move TLP Log handling to its own file
  PCI: Don't expose pcie_read_tlp_log() outside PCI subsystem
2025-01-23 13:04:50 -06:00
Alex Williamson 4453f36086 PCI: Batch BAR sizing operations
Toggling memory enable is free on bare metal, but potentially expensive
in virtualized environments as the device MMIO spaces are added and
removed from the VM address space, including DMA mapping of those spaces
through the IOMMU where peer-to-peer is supported.  Currently memory
decode is disabled around sizing each individual BAR, even for SR-IOV
BARs while VF Enable is cleared.

This can be better optimized for virtual environments by sizing a set
of BARs at once, stashing the resulting mask into an array, while only
toggling memory enable once.  This also naturally improves the SR-IOV
path as the caller becomes responsible for any necessary decode disables
while sizing BARs, therefore SR-IOV BARs are sized relying only on the
VF Enable rather than toggling the PF memory enable in the command
register.

Link: https://lore.kernel.org/r/20250120182202.1878581-1-alex.williamson@redhat.com
Reported-by: Mitchell Augustin <mitchell.augustin@canonical.com>
Link: https://lore.kernel.org/r/CAHTA-uYp07FgM6T1OZQKqAdSA5JrZo0ReNEyZgQZub4mDRrV5w@mail.gmail.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Tested-by: Mitchell Augustin <mitchell.augustin@canonical.com>
Reviewed-by: Mitchell Augustin <mitchell.augustin@canonical.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
2025-01-23 11:05:20 -06:00
Ilpo Järvinen f68ea779d9 PCI: Add pcie_print_tlp_log() to print TLP Header and Prefix Log
Add pcie_print_tlp_log() to print TLP Header and Prefix Log.  Print End-End
Prefixes only if they are non-zero.

Consolidate the few places which currently print TLP using custom
formatting.

Link: https://lore.kernel.org/r/20250114170840.1633-9-ilpo.jarvinen@linux.intel.com
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
[bhelgaas: commit log]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2025-01-16 12:05:43 -06:00
Ilpo Järvinen ad41ddeeac PCI: Add TLP Prefix reading to pcie_read_tlp_log()
pcie_read_tlp_log() handles only 4 Header Log DWORDs but TLP Prefix Log
(PCIe r6.1 secs 7.8.4.12 & 7.9.14.13) may also be present.

Generalize pcie_read_tlp_log() and struct pcie_tlp_log to also handle TLP
Prefix Log. The relevant registers are formatted identically in AER and DPC
Capability, but has these variations:

  a) The offsets of TLP Prefix Log registers vary.

  b) DPC RP PIO TLP Prefix Log register can be < 4 DWORDs.

  c) AER TLP Prefix Log Present (PCIe r6.1 sec 7.8.4.7) can indicate Prefix
     Log is not present.

Therefore callers must pass the offset of the TLP Prefix Log register and
the entire length to pcie_read_tlp_log() to be able to read the correct
number of TLP Prefix DWORDs from the correct offset.

Link: https://lore.kernel.org/r/20250114170840.1633-8-ilpo.jarvinen@linux.intel.com
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
[bhelgaas: squash ternary fix from
https://lore.kernel.org/r/20250116172019.88116-1-colin.i.king@gmail.com]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2025-01-16 12:04:38 -06:00
Bjorn Helgaas ddedc08e80 PCI: Unexport of_pci_parse_bus_range()
of_pci_parse_bus_range() is only used in drivers/pci/of.c, so make it
static and unexport it.

Link: https://lore.kernel.org/r/20250113231557.441289-2-helgaas@kernel.org
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rob Herring (Arm) <robh@kernel.org>
Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
2025-01-15 15:24:39 -06:00
Ilpo Järvinen 10269d5781
PCI/sysfs: Move reset related sysfs code to correct file
Most PCI sysfs code and structs are in a dedicated file but a few reset
related things remain in pci.c. Move also them to pci-sysfs.c and drop
pci_dev_reset_method_attr_is_visible() as it is 100% duplicate of
pci_dev_reset_attr_is_visible().

Link: https://lore.kernel.org/r/20241028174046.1736-2-ilpo.jarvinen@linux.intel.com
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
2025-01-15 03:54:22 +00:00
Ilpo Järvinen a71c59269e PCI: Move TLP Log handling to its own file
TLP Log is a PCIe feature and is processed only by AER and DPC.
Configwise, DPC depends AER being enabled. In lack of better place, the TLP
Log handling code was initially placed into pci.c but it can be easily
placed in a separate file.

Move TLP Log handling code to its own file under pcie/ subdirectory and
include it only when AER is enabled.

Link: https://lore.kernel.org/r/20250114170840.1633-3-ilpo.jarvinen@linux.intel.com
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Yazen Ghannam <yazen.ghannam@amd.com>
2025-01-14 17:38:18 -06:00
Ilpo Järvinen 013525583f PCI: Don't expose pcie_read_tlp_log() outside PCI subsystem
pcie_read_tlp_log() was exposed by the commit 0a5a46a6a6 ("PCI/AER:
Generalize TLP Header Log reading") with the intent that drivers could use
it, but the PCI maintainer later decided that drivers should be encouraged
to use PCI core diagnostic logging of generic AER registers rather than
building their own.

Drivers that currently implement their own diagnostic logging include ixgbe
(ixgbe_io_error_detected()) and iwlwifi (iwl_trans_pcie_dump_regs()).

Remove the unwanted EXPORT of pcie_read_tlp_log() and remove it from
include/linux/aer.h.

Link: https://lore.kernel.org/r/20250114170840.1633-2-ilpo.jarvinen@linux.intel.com
Link: https://lore.kernel.org/all/20240322193011.GA701027@bhelgaas/
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
[bhelgaas: commit log]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Yazen Ghannam <yazen.ghannam@amd.com>
2025-01-14 17:24:27 -06:00
Bjorn Helgaas ab02bafcec Merge branch 'pci/tph'
- Add and document TLP Processing Hints (TPH) support so drivers can enable
  and disable TPH and the kernel can save/restore TPH configuration (Wei
  Huang)

- Add TPH Steering Tag support so drivers can retrieve Steering Tag values
  associated with specific CPUs via an ACPI _DSM to direct DMA writes
  closer to their consumers (Wei Huang)

* pci/tph:
  PCI/TPH: Add TPH documentation
  PCI/TPH: Add Steering Tag support
  PCI: Add TLP Processing Hints (TPH) support
2024-11-25 13:40:55 -06:00
Bjorn Helgaas d985e2beb9 Merge branch 'pci/reset'
- Add sysfs 'reset_subordinate' to reset hierarchy below bridge (Keith
  Busch)

- Warn if we reset a running device where driver didn't register
  pci_error_handlers notification callbacks (Keith Busch)

* pci/reset:
  PCI: Warn if a running device is unaware of reset
  PCI: Add 'reset_subordinate' to reset hierarchy below bridge
2024-11-25 13:40:54 -06:00
Bjorn Helgaas ce1deca962 Merge branch 'pci/pwrctl'
- Use of_platform_device_create() instead of of_platform_populate() to
  create pwrctl platform devices so we can control it based on the child
  nodes (Manivannan Sadhasivam)

- Create pwrctrl platform devices only if there's a relevant power supply
  property (Manivannan Sadhasivam)

- Add device link from the pwrctl supplier to the PCI dev to ensure pwrctl
  drivers are probed before the PCI dev driver; this avoids a race where
  pwrctl could change device power state while the PCI driver was active
  (Manivannan Sadhasivam)

- Find pwrctl device for removal with of_find_device_by_node() instead of
  searching all children of the parent (Manivannan Sadhasivam)

- Rename 'pwrctl' to 'pwrctrl' to use the same 'ctrl' suffix as 'bwctrl'
  and other PCI files to reduce confusion (Bjorn Helgaas)

* pci/pwrctl:
  PCI/pwrctrl: Rename pwrctrl functions and structures
  PCI/pwrctrl: Rename pwrctl files to pwrctrl
  PCI/pwrctl: Remove pwrctl device without iterating over all children of pwrctl parent
  PCI/pwrctl: Ensure that pwrctl drivers are probed before PCI client drivers
  PCI/pwrctl: Create pwrctl device only if at least one power supply is present
  PCI/pwrctl: Use of_platform_device_create() to create pwrctl devices

# Conflicts:
#	drivers/pci/bus.c
#	drivers/pci/remove.c
2024-11-25 13:40:54 -06:00
Bjorn Helgaas 5d756f3fa8 Merge branch 'pci/locking'
- Make pci_stop_dev() and pci_destroy_dev() concurrent safe (Keith Busch)

- Move __pci_walk_bus() mutex up into the caller, which avoids the need for
  a parameter to control locking (Keith Busch)

- Simplify __pci_walk_bus() by making it recursive (Keith Busch)

- Unexport pci_walk_bus_locked(), which is only used internally by the PCI
  core (Keith Busch)

* pci/locking:
  PCI: Unexport pci_walk_bus_locked()
  PCI: Convert __pci_walk_bus() to be recursive
  PCI: Move __pci_walk_bus() mutex to where we need it
  PCI: Make pci_destroy_dev() concurrent safe
  PCI: Make pci_stop_dev() concurrent safe
2024-11-25 13:40:45 -06:00
Manivannan Sadhasivam 278dd091e9
PCI/pwrctl: Create pwrctl device only if at least one power supply is present
Currently, pwrctl devices are created if the corresponding PCI nodes are
defined in devicetree. But this is not correct, because not all PCI nodes
require pwrctl support. Pwrctl comes into the picture only when the device
requires kernel to manage its power state. This can be determined using the
power supply properties present in the devicetree node of the device.

Add of_pci_supply_present() to check whether the devicetree contains at
least one power supply property for a device. If one is present, create a
pwrctl device for that PCI node.

Suggested-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Fixes: 8fb18619d9 ("PCI/pwrctl: Create platform devices for child OF nodes of the port node")
Link: https://lore.kernel.org/r/20241025-pci-pwrctl-rework-v2-2-568756156cbe@linaro.org
Tested-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Tested-by: Krishna chaitanya chundru <quic_krichai@quicinc.com>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
[bhelgaas: rename of_pci_is_supply_present() to of_pci_supply_present() for
readability]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
Reviewed-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Cc: stable+noautosel@kernel.org		# Depends on of_platform_device_create() rework
2024-11-21 16:01:04 +00:00
Bjorn Helgaas ba58eee1c5 PCI: Drop duplicate pcie_get_speed_cap(), pcie_get_width_cap() declarations
6cf57be0f7 ("PCI: Add pcie_get_speed_cap() to find max supported link
speed") and c70b65fb7f ("PCI: Add pcie_get_width_cap() to find max
supported link width") added declarations to drivers/pci/pci.h.

576c7218a1 ("PCI: Export pcie_get_speed_cap and pcie_get_width_cap")
subsequently added duplicates to include/linux/pci.h.

Remove the originals from drivers/pci/pci.h.  Both interfaces are used by
amdgpu, so they must be in include/linux/pci.h.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Acked-by: Krzysztof Wilczyński <kw@linux.com>
2024-11-16 10:09:30 -06:00
Ilpo Järvinen de9a6c8d5d PCI/bwctrl: Add pcie_set_target_speed() to set PCIe Link Speed
Currently, PCIe Link Speeds are adjusted by custom code rather than in a
common function provided in PCI core. The PCIe bandwidth controller
(bwctrl) introduces an in-kernel API, pcie_set_target_speed(), to set PCIe
Link Speed.

Convert Target Speed quirk to use the new API. The Target Speed quirk runs
very early when bwctrl is not yet probed for a Port and can also run later
when bwctrl is already setup for the Port, which requires the per port
mutex (set_speed_mutex) to be only taken if the bwctrl setup is already
complete.

The new API is also intended to be used in an upcoming commit that adds a
thermal cooling device to throttle PCIe bandwidth when thermal thresholds
are reached.

The PCIe bandwidth control procedure is as follows. The highest speed
supported by the Port and the PCIe device which is not higher than the
requested speed is selected and written into the Target Link Speed in the
Link Control 2 Register. Then bandwidth controller retrains the PCIe Link.

Bandwidth Notifications enable the cur_bus_speed in the struct pci_bus to
keep track PCIe Link Speed changes. While Bandwidth Notifications should
also be generated when bandwidth controller alters the PCIe Link Speed, a
few platforms do not deliver LMBS interrupt after Link Training as
expected. Thus, after changing the Link Speed, bandwidth controller makes
additional read for the Link Status Register to ensure cur_bus_speed is
consistent with the new PCIe Link Speed.

Link: https://lore.kernel.org/r/20241018144755.7875-8-ilpo.jarvinen@linux.intel.com
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
[bhelgaas: squash devm_mutex_init() error checking from
https://lore.kernel.org/r/20241030163139.2111689-1-andriy.shevchenko@linux.intel.com,
drop export of pcie_set_target_speed()]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2024-11-16 10:09:30 -06:00
Ilpo Järvinen 665745f274 PCI/bwctrl: Re-add BW notification portdrv as PCIe BW controller
This mostly reverts the commit b4c7d2076b ("PCI/LINK: Remove bandwidth
notification"). An upcoming commit extends this driver building PCIe
bandwidth controller on top of it.

PCIe bandwidth notifications were first added in the commit e8303bb7a7
("PCI/LINK: Report degraded links via link bandwidth notification") but
later had to be removed. The significant changes compared with the old
bandwidth notification driver include:

1) Don't print the notifications into kernel log, just keep the Link
   Speed cached in struct pci_bus updated. While somewhat unfortunate,
   the log spam was the source of complaints that eventually lead to
   the removal of the bandwidth notifications driver (see the links
   below for further information).

2) Besides the Link Bandwidth Management Interrupt, also enable Link
   Autonomous Bandwidth Interrupt to cover the other source of bandwidth
   changes.

3) Handle Link Speed updates robustly. Refresh the cached Link Speed
   when enabling Bandwidth Notification Interrupts, and solve the race
   between Link Speed read and LBMS/LABS update in
   pcie_bwnotif_irq_thread().

4) Use concurrency safe LNKCTL RMW operations.

5) The driver is now called PCIe bwctrl (bandwidth controller) instead
   of just bandwidth notifications because of increased scope and
   functionality within the driver.

6) Coexist with the Target Link Speed quirk in pcie_failed_link_retrain().
   Provide LBMS counting API for it.

7) Tweaks to variable/functions names for consistency and length reasons.

Bandwidth Notifications enable the cur_bus_speed in the struct pci_bus to
keep track PCIe Link Speed changes.

[bhelgaas: This is based on previous work by Alexandru Gagniuc
<mr.nuke.me@gmail.com>; see e8303bb7a7 ("PCI/LINK: Report degraded links
via link bandwidth notification")]

Link: https://lore.kernel.org/r/20241018144755.7875-7-ilpo.jarvinen@linux.intel.com
Link: https://lore.kernel.org/all/20190429185611.121751-1-helgaas@kernel.org/
Link: https://lore.kernel.org/linux-pci/20190501142942.26972-1-keith.busch@intel.com/
Link: https://lore.kernel.org/linux-pci/20200115221008.GA191037@google.com/
Suggested-by: Lukas Wunner <lukas@wunner.de> # Building bwctrl on top of bwnotif
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
[bhelgaas: squash fix to drop IRQF_ONESHOT and convert to hardirq handler:
https://lore.kernel.org/r/20241115165717.15233-1-ilpo.jarvinen@linux.intel.com]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Tested-by: Stefan Wahren <wahrenst@gmx.net>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2024-11-16 10:09:04 -06:00
Keith Busch 2fa046449a PCI: Add 'reset_subordinate' to reset hierarchy below bridge
The "bus" and "cxl_bus" reset methods reset a device by asserting Secondary
Bus Reset on the bridge leading to the device.  These only work if the
device is the only device below the bridge.

Add a sysfs 'reset_subordinate' attribute on bridges that can assert
Secondary Bus Reset regardless of how many devices are below the bridge.

This resets all the devices below a bridge in a single command, including
the locking and config space save/restore that reset methods normally do.

This may be the only way to reset devices that don't support other reset
methods (ACPI, FLR, PM reset, etc).

Link: https://lore.kernel.org/r/20241025222755.3756162-1-kbusch@meta.com
Signed-off-by: Keith Busch <kbusch@kernel.org>
[bhelgaas: commit log, add capable(CAP_SYS_ADMIN) check]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Amey Narkhede <ameynarkhede03@gmail.com>
2024-11-13 16:43:34 -06:00
Keith Busch 38a18dfe90 PCI: Unexport pci_walk_bus_locked()
There's only one user of pci_walk_bus_locked(), and it's internal to the
PCI core.  Unexport it and make it private to drivers/pci/.

Link: https://lore.kernel.org/r/20241022224851.340648-6-kbusch@meta.com
Signed-off-by: Keith Busch <kbusch@kernel.org>
[bhelgaas: move decl to drivers/pci/pci.h]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Davidlohr Bueso <dave@stgolabs.net>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
2024-11-11 14:32:12 -06:00
Ilpo Järvinen e93d9fcfd7 PCI: Refactor pcie_update_link_speed()
pcie_update_link_speed() is passed the Link Status register but not all
callers have that value at hand nor need the value.

Refactor pcie_update_link_speed() to include reading the Link Status
register and create __pcie_update_link_speed() which can be used by the
hotplug code that has the register value at hand beforehand (and needs the
value for other purposes).

Link: https://lore.kernel.org/r/20241018144755.7875-5-ilpo.jarvinen@linux.intel.com
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2024-11-11 14:20:04 -06:00
Ilpo Järvinen d2bd39c045 PCI: Store all PCIe Supported Link Speeds
The PCIe bandwidth controller added by a subsequent commit will require
selecting PCIe Link Speeds that are lower than the Maximum Link Speed.

The struct pci_bus only stores max_bus_speed. Even if PCIe r6.1 sec 8.2.1
currently disallows gaps in supported Link Speeds, the Implementation Note
in PCIe r6.1 sec 7.5.3.18, recommends determining supported Link Speeds
using the Supported Link Speeds Vector in the Link Capabilities 2 Register
(when available) to "avoid software being confused if a future
specification defines Links that do not require support for all slower
speeds."

Reuse code in pcie_get_speed_cap() to add pcie_get_supported_speeds() to
query the Supported Link Speeds Vector of a PCIe device. The value is taken
directly from the Supported Link Speeds Vector or synthesized from the Max
Link Speed in the Link Capabilities Register when the Link Capabilities 2
Register is not available.

The Supported Link Speeds Vector in the Link Capabilities Register 2
corresponds to the bus below on Root Ports and Downstream Ports, whereas it
corresponds to the bus above on Upstream Ports and Endpoints (PCIe r6.1 sec
7.5.3.18):

  Supported Link Speeds Vector - This field indicates the supported Link
  speed(s) of the associated Port.

Add supported_speeds into the struct pci_dev that caches the
Supported Link Speeds Vector.

supported_speeds contains a set of Link Speeds only in the case where PCIe
Link Speed can be determined. Root Complex Integrated Endpoints do not have
a well-defined Link Speed because they do not implement either of the Link
Capabilities Registers, which is allowed by PCIe r6.1 sec 7.5.3 (the same
limitation applies to determining cur_bus_speed and max_bus_speed that are
PCI_SPEED_UNKNOWN in such case). This is of no concern from PCIe bandwidth
controller point of view because such devices are not attached into a PCIe
Root Port that could be controlled.

The supported_speeds field keeps the extra reserved zero at the least
significant bit to match the Link Capabilities 2 Register layout.

An attempt was made to store supported_speeds field into the struct pci_bus
as an intersection of both ends of the Link, however, the subordinate
struct pci_bus is not available early enough. The Target Speed quirk (in
pcie_failed_link_retrain()) can run either during initial scan or later,
requiring it to use the API provided by the PCIe bandwidth controller to
set the Target Link Speed in order to co-exist with the bandwidth
controller. When the Target Speed quirk is calling the bandwidth controller
during initial scan, the struct pci_bus is not yet initialized. As such,
storing supported_speeds into the struct pci_bus is not viable.

Suggested-by: Lukas Wunner <lukas@wunner.de>
Link: https://lore.kernel.org/r/20241018144755.7875-4-ilpo.jarvinen@linux.intel.com
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
[bhelgaas: move pcie_get_supported_speeds() decl to drivers/pci/pci.h]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2024-11-11 14:19:30 -06:00
Keith Busch e3f30d563a PCI: Make pci_destroy_dev() concurrent safe
Use an atomic flag instead of the racy check against the device's kobj
parent. We shouldn't be poking into device implementation details at this
level anyway.

Link: https://lore.kernel.org/r/20241022224851.340648-3-kbusch@meta.com
Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2024-11-11 13:06:02 -06:00
Keith Busch 93093ea1f0 PCI: Make pci_stop_dev() concurrent safe
Use the atomic ADDED flag to ensure concurrent callers can't attempt to
stop the device multiple times. Callers should currently all be holding the
pci_rescan_remove_lock, so there shouldn't be an existing race. But that
global lock can cause lock dependency issues, so this is preparing to
reduce reliance on that lock by using the existing existing atomic bit ops.

Link: https://lore.kernel.org/r/20241022224851.340648-2-kbusch@meta.com
Signed-off-by: Keith Busch <kbusch@kernel.org>
[bhelgaas: squash https://lore.kernel.org/r/20241111180659.3321671-1-kbusch@meta.com]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2024-11-11 13:05:50 -06:00
Wei Huang f69767a1ad PCI: Add TLP Processing Hints (TPH) support
Add support for PCIe TLP Processing Hints (TPH) support (see PCIe r6.2,
sec 6.17).

Add TPH register definitions in pci_regs.h, including the TPH Requester
capability register, TPH Requester control register, TPH Completer
capability, and the ST fields of MSI-X entry.

Introduce pcie_enable_tph() and pcie_disable_tph(), enabling drivers to
toggle TPH support and configure specific ST mode as needed. Also add a new
kernel parameter, "pci=notph", allowing users to disable TPH support across
the entire system.

Link: https://lore.kernel.org/r/20241002165954.128085-2-wei.huang2@amd.com
Co-developed-by: Jing Liu <jing2.liu@intel.com>
Co-developed-by: Paul Luse <paul.e.luse@linux.intel.com>
Co-developed-by: Eric Van Tassell <Eric.VanTassell@amd.com>
Signed-off-by: Jing Liu <jing2.liu@intel.com>
Signed-off-by: Paul Luse <paul.e.luse@linux.intel.com>
Signed-off-by: Eric Van Tassell <Eric.VanTassell@amd.com>
Signed-off-by: Wei Huang <wei.huang2@amd.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Ajit Khaparde <ajit.khaparde@broadcom.com>
Reviewed-by: Somnath Kotur <somnath.kotur@broadcom.com>
Reviewed-by: Andy Gospodarek <andrew.gospodarek@broadcom.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Lukas Wunner <lukas@wunner.de>
2024-10-02 16:20:01 -05:00
Bjorn Helgaas 5dc07a20ac Merge branch 'pci/misc'
- Check pcie_find_root_port() return in x86 fixups to avoid NULL pointer
  dereferences (Samasth Norway Ananda)

- Make pci_bus_type constant (Kunwu Chan)

- Remove unused declarations of __pci_pme_wakeup() and pci_vpd_release()
  (Yue Haibing)

- Remove any leftover .*.cmd files with make clean (zhang jiao)

* pci/misc:
  PCI: Fix typos
  PCI/VPD: Remove pci_vpd_release() unused declarations
  PCI/PM: Remove __pci_pme_wakeup() unused declarations
  PCI: Make pci_bus_type constant
  x86/PCI: Check pcie_find_root_port() return for NULL
2024-09-19 14:25:34 -05:00
Bjorn Helgaas d1624da381 Merge branch 'pci/controller/j721e'
- Add DT "ti,syscon-acspcie-proxy-ctrl" and driver support to enable the
  ACSPCIE module to drive Refclk for the Endpoint (Siddharth Vadapalli)

- Extract the cadence link setup from cdns_pcie_host_setup() so link setup
  can be done separately during resume (Thomas Richard)

- Use dev_err_probe() to simplify j721e probe (Thomas Richard)

- Add T_PERST_CLK_US definition for the mandatory delay between Refclk
  becoming stable and PERST# being deasserted (Thomas Richard)

- Add j721e suspend and resume support (Théo Lebrun)

* pci/controller/j721e:
  PCI: j721e: Add suspend and resume support
  PCI: j721e: Use T_PERST_CLK_US macro
  PCI: Add T_PERST_CLK_US macro
  PCI: j721e: Add reset GPIO to struct j721e_pcie
  PCI: j721e: Use dev_err_probe() in the probe() function
  PCI: cadence: Set cdns_pcie_host_init() global
  PCI: cadence: Extract link setup sequence from cdns_pcie_host_setup()
  PCI: j721e: Enable ACSPCIE Refclk if "ti,syscon-acspcie-proxy-ctrl" exists
  dt-bindings: PCI: ti,j721e-pci-host: Add ACSPCIE proxy control property
2024-09-19 14:25:30 -05:00
Bjorn Helgaas 9d4f1c0747 Merge branch 'pci/npem'
- Initialize leds class earlier (with an unfortunate Makefile ordering
  change) so the PCI NPEM driver can use it (Mariusz Tkaczyk)

- Add Native PCIe Enclosure Management (NPEM) support for sysfs control of
  NVMe RAID storage indicators (ok/fail/locate/rebuild/etc) (Mariusz
  Tkaczyk)

- Add support for the ACPI _DSM PCIe SSD status LED management, which is
  functionally similar to NPEM but mediated by platform firmware (Mariusz
  Tkaczyk)

* pci/npem:
  PCI/NPEM: Add _DSM PCIe SSD status LED management
  PCI/NPEM: Add Native PCIe Enclosure Management support
  leds: Init leds class earlier
2024-09-19 14:25:26 -05:00
Bjorn Helgaas dffe4cca2e Merge branch 'pci/enumeration'
- Clear LBMS bit after a manual link retrain so we don't try to retrain a
  link when there's no downstream device anymore (Maciej W. Rozycki)

- Revert to the original link speed after retraining fails instead of
  leaving it restricted to 2.5GT/s, so a future device has a chance to use
  higher speeds (Maciej W. Rozycki)

- Correct interpretation of pcie_retrain_link() return status and update it
  to return 0/errno instead of true/false (Maciej W.  Rozycki)

* pci/enumeration:
  PCI: Use an error code with PCIe failed link retraining
  PCI: Correct error reporting with PCIe failed link retraining
  PCI: Revert to the original speed after PCIe failed link retraining
  PCI: Clear the LBMS bit after a link retrain
2024-09-19 14:25:25 -05:00
Bjorn Helgaas dceed69701 Merge branch 'pci/devres'
- Export pcim_request_region(), a managed counterpart of
  pci_request_region(), for use by drivers (Philipp Stanner)

- Request the PCI BAR used by xboxvideo (Philipp Stanner)

- Export pcim_iomap_region() and deprecate pcim_iomap_regions() (Philipp
  Stanner)

- Request and map drm/ast BARs with pcim_iomap_region() (Philipp Stanner)

* pci/devres:
  drm/ast: Request PCI BAR with devres
  PCI: Deprecate pcim_iomap_regions() in favor of pcim_iomap_region()
  drm/vboxvideo: Add PCI region request
  PCI: Make pcim_request_region() a public function
2024-09-19 14:25:25 -05:00
Bjorn Helgaas 87f10faf16 PCI: Rename CRS Completion Status to RRS
PCIe r6.0 changed the abbreviation for "Configuration Request Retry Status"
Completion Status from "CRS" to "RRS" and uses the terminology of
"Configuration RRS Software Visibility" instead of "CRS Software
Visibility".

Align the Linux usage with the r6.0 spec language.  No functional change
intended.

It's confusing to make this change, but I think "RRS" *is* a better
abbreviation because it was easy to interpret "CRS" as "Completion Retry
Status", which really didn't make any sense.

Link: https://lore.kernel.org/r/20240827234848.4429-4-helgaas@kernel.org
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2024-09-10 19:52:30 -05:00
Bjorn Helgaas d591f6804e PCI: Wait for device readiness with Configuration RRS
After a device reset, delays are required before the device can
successfully complete config accesses.  PCIe r6.0, sec 6.6, specifies some
delays required before software can perform config accesses.  Devices that
require more time after those delays may respond to config accesses with
Configuration Request Retry Status (RRS) completions.

Callers of pci_dev_wait() are responsible for delays until the device can
respond to config accesses.  pci_dev_wait() waits any additional time until
the device can successfully complete config accesses.

Reading config space of devices that are not present or not ready typically
returns ~0 (PCI_ERROR_RESPONSE).  Previously we polled the Command register
until we got a value other than ~0.  This is sometimes a problem because
Root Complex handling of RRS completions may include several retries and
implementation-specific behavior that is invisible to software (see sec
2.3.2), so the exponential backoff in pci_dev_wait() may not work as
intended.

Linux enables Configuration RRS Software Visibility on all Root Ports that
support it.  If it is enabled, read the Vendor ID instead of the Command
register.  RRS completions cause immediate return of the 0x0001 reserved
Vendor ID value, so the pci_dev_wait() backoff works correctly.

When a read of Vendor ID eventually completes successfully by returning a
non-0x0001 value (the Vendor ID or 0xffff for VFs), the device should be
initialized and ready to respond to config requests.

For conventional PCI devices or devices below Root Ports that don't support
Configuration RRS Software Visibility, poll the Command register as before.

This was developed independently, but is very similar to Stanislav
Spassov's previous work at
https://lore.kernel.org/linux-pci/20200223122057.6504-1-stanspas@amazon.com

Link: https://lore.kernel.org/r/20240827234848.4429-2-helgaas@kernel.org
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Tested-by: Duc Dang <ducdang@google.com>
2024-09-10 19:52:23 -05:00
Maciej W. Rozycki 59100eb248
PCI: Use an error code with PCIe failed link retraining
Given how the call place in pcie_wait_for_link_delay() got structured now,
and that pcie_retrain_link() returns a potentially useful error code,
convert pcie_failed_link_retrain() to return an error code rather than a
boolean status, fixing handling at the call site mentioned.  Update the
other call site accordingly.

Fixes: 1abb473903 ("Merge branch 'pci/enumeration'")
Link: https://lore.kernel.org/r/alpine.DEB.2.21.2408091156530.61955@angie.orcam.me.uk
Reported-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/aa2d1c4e-9961-d54a-00c7-ddf8e858a9b0@linux.intel.com/
Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Cc: <stable@vger.kernel.org> # v6.5+
2024-09-09 14:03:36 +00:00