linux.git/drivers/pci/Kconfig, branch vsnprintf

Merge branch 'pci/tph'

2024-11-25T19:40:55+00:00

- 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

PCI/pwrctrl: Rename pwrctl files to pwrctrl

2024-11-21T16:01:24+00:00

To slightly reduce confusion between "pwrctl" (the power controller and
power sequencing framework) and "bwctrl" (the bandwidth controller),
rename "pwrctl" to "pwrctrl" so they use the same "ctrl" suffix.

Rename drivers/pci/pwrctl/ to drivers/pci/pwrctrl/, including the related
MAINTAINERS, include file (include/linux/pci-pwrctl.h), Makefile, and
Kconfig changes.

This is the minimal rename of files only.  A subsequent commit will rename
functions and data structures.

Link: https://lore.kernel.org/r/20241115214428.2061153-2-helgaas@kernel.org
Signed-off-by: Bjorn Helgaas 
Signed-off-by: Krzysztof Wilczyński 
Acked-by: Krzysztof Wilczyński

PCI: Add TLP Processing Hints (TPH) support

2024-10-02T21:20:01+00:00

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 
Co-developed-by: Paul Luse 
Co-developed-by: Eric Van Tassell 
Signed-off-by: Jing Liu 
Signed-off-by: Paul Luse 
Signed-off-by: Eric Van Tassell 
Signed-off-by: Wei Huang 
Signed-off-by: Bjorn Helgaas 
Reviewed-by: Ajit Khaparde 
Reviewed-by: Somnath Kotur 
Reviewed-by: Andy Gospodarek 
Reviewed-by: Jonathan Cameron 
Reviewed-by: Lukas Wunner

PCI/NPEM: Add Native PCIe Enclosure Management support

2024-09-04T22:25:12+00:00

Native PCIe Enclosure Management (NPEM, PCIe r6.1 sec 6.28) allows managing
LEDs in storage enclosures. NPEM is indication oriented and it does not
give direct access to LEDs. Although each indication *could* represent an
individual LED, multiple indications could also be represented as a single,
multi-color LED or a single LED blinking in a specific interval.  The
specification leaves that open.

Each enabled indication (capability register bit on) is represented as a
ledclass_dev which can be controlled through sysfs. For every ledclass
device only 2 brightness states are allowed: LED_ON (1) or LED_OFF (0).
This corresponds to the NPEM control register (Indication bit on/off).

Ledclass devices appear in sysfs as child devices (subdirectory) of PCI
device which has an NPEM Extended Capability and indication is enabled in
NPEM capability register. For example, these are LEDs created for pcieport
"10000:02:05.0" on my setup:

  leds/
  ├── 10000:02:05.0:enclosure:fail
  ├── 10000:02:05.0:enclosure:locate
  ├── 10000:02:05.0:enclosure:ok
  └── 10000:02:05.0:enclosure:rebuild

They can be also found in "/sys/class/leds" directory. The parent PCIe
device domain/bus/device/function address is used to guarantee uniqueness
across leds subsystem.

To enable/disable a "fail" indication, the "brightness" file can be edited:

  echo 1 > ./leds/10000:02:05.0:enclosure:fail/brightness
  echo 0 > ./leds/10000:02:05.0:enclosure:fail/brightness

PCIe r6.1, sec 7.9.19.2 defines the possible indications.

Multiple indications for same parent PCIe device can conflict and hardware
may update them when processing new request. To avoid issues, driver
refresh all indications by reading back control register.

This driver expects to be the exclusive NPEM extended capability manager.
It waits up to 1 second after imposing new request, it doesn't verify if
controller is busy before write, and it assumes the mutex lock gives
protection from concurrent updates.

If _DSM LED management is available, we assume the platform may be using
NPEM for its own purposes (see PCI Firmware Spec r3.3 sec 4.7), so the
driver does not use NPEM. A future patch will add _DSM support; an info
message notes whether NPEM or _DSM is being used.

NPEM is a PCIe extended capability so it should be registered in
pcie_init_capabilities() but it is not possible due to LED dependency.  The
parent pci_device must be added earlier for led_classdev_register() to be
successful. NPEM does not require configuration on kernel side, so it is
safe to register LED devices later.

Link: https://lore.kernel.org/r/20240904104848.23480-3-mariusz.tkaczyk@linux.intel.com
Suggested-by: Lukas Wunner 
Signed-off-by: Mariusz Tkaczyk 
Signed-off-by: Bjorn Helgaas 
Tested-by: Stuart Hayes 
Reviewed-by: Christoph Hellwig 
Reviewed-by: Ilpo Järvinen

PCI/pwrctl: Add PCI power control core code

2024-06-12T11:20:56+00:00

Some PCI devices must be powered-on before they can be detected on the
bus. Introduce a simple framework reusing the existing PCI OF
infrastructure.

The way this works is: a DT node representing a PCI device connected to
the port can be matched against its power control platform driver. If
the match succeeds, the driver is responsible for powering-up the device
and calling pci_pwrctl_device_set_ready() which will trigger a PCI bus
rescan as well as subscribe to PCI bus notifications.

When the device is detected and created, we'll make it consume the same
DT node that the platform device did. When the device is bound, we'll
create a device link between it and the parent power control device.

Tested-by: Amit Pundir 
Tested-by: Neil Armstrong  # on SM8550-QRD, SM8650-QRD & SM8650-HDK
Tested-by: Caleb Connolly  # OnePlus 8T
Acked-by: Bjorn Helgaas 
Link: https://lore.kernel.org/r/20240612082019.19161-5-brgl@bgdev.pl
Signed-off-by: Bartosz Golaszewski

PCI: Move pci_iomap.c to drivers/pci/

2024-02-12T16:35:40+00:00

The entirety of pci_iomap.c is guarded by an #ifdef CONFIG_PCI. It,
consequently, does not belong to lib/ because it is not generic
infrastructure.

Move pci_iomap.c to drivers/pci/ and implement the necessary changes to
Makefiles and Kconfigs.

Update MAINTAINERS file.

Update Documentation.

Link: https://lore.kernel.org/r/20240131090023.12331-3-pstanner@redhat.com
[bhelgaas: squash in https://lore.kernel.org/r/20240212150934.24559-1-pstanner@redhat.com]
Suggested-by: Danilo Krummrich 
Signed-off-by: Philipp Stanner 
Signed-off-by: Bjorn Helgaas 
Reviewed-by: Arnd Bergmann

PCI: Replace unnecessary UTF-8 in Kconfig

2023-10-06T19:30:48+00:00

The CONFIG_PCI_P2PDMA Kconfig help text contains a Cyrillic small "Dze"
(ѕ).  When menuconfig renders it, it looks like "Enable ~U drivers" instead
of "Enables drivers".

Replace it by a plain "s" so the help text is displayed correctly by
menuconfig.

Uwe Kleine-König  later posted the same
patch at
https://lore.kernel.org/r/20231006150209.87666-1-u.kleine-koenig@pengutronix.de

Link: https://lore.kernel.org/r/1658301723-111283-1-git-send-email-liusong@linux.alibaba.com
Tested-by: Randy Dunlap 
Signed-off-by: Liu Song 
[bhelgaas: commit log, add Uwe's report]
Signed-off-by: Bjorn Helgaas 
Acked-by: Randy Dunlap

PCI: Fix CONFIG_PCI_DYNAMIC_OF_NODES kconfig dependencies

2023-09-05T17:42:28+00:00

Generating interrupt-map property depends on of_irq_parse_raw() which
is enabled by CONFIG_OF_IRQ. Change CONFIG_PCI_DYNAMIC_OF_NODES
dependency from CONFIG_OF to CONFIG_OF_IRQ.

Closes: https://lore.kernel.org/linux-devicetree/2187619d-55bc-41bb-bbb4-6059399db997@roeck-us.net/
Fixes: 407d1a51921e ("PCI: Create device tree node for bridge")
Link: https://lore.kernel.org/r/1693505947-29786-1-git-send-email-lizhi.hou@amd.com
Reported-by: Guenter Roeck 
Signed-off-by: Lizhi Hou 
Signed-off-by: Bjorn Helgaas

PCI: Create device tree node for bridge

2023-08-22T19:56:09+00:00

The PCI endpoint device such as Xilinx Alveo PCI card maps the register
spaces from multiple hardware peripherals to its PCI BAR. Normally,
the PCI core discovers devices and BARs using the PCI enumeration process.
There is no infrastructure to discover the hardware peripherals that are
present in a PCI device, and which can be accessed through the PCI BARs.

Apparently, the device tree framework requires a device tree node for the
PCI device. Thus, it can generate the device tree nodes for hardware
peripherals underneath. Because PCI is self discoverable bus, there might
not be a device tree node created for PCI devices. Furthermore, if the PCI
device is hot pluggable, when it is plugged in, the device tree nodes for
its parent bridges are required. Add support to generate device tree node
for PCI bridges.

Add an of_pci_make_dev_node() interface that can be used to create device
tree node for PCI devices.

Add a PCI_DYNAMIC_OF_NODES config option. When the option is turned on,
the kernel will generate device tree nodes for PCI bridges unconditionally.

Initially, add the basic properties for the dynamically generated device
tree nodes which include #address-cells, #size-cells, device_type,
compatible, ranges, reg.

Acked-by: Bjorn Helgaas 
Signed-off-by: Lizhi Hou 
Link: https://lore.kernel.org/r/1692120000-46900-3-git-send-email-lizhi.hou@amd.com
Signed-off-by: Rob Herring

scatterlist: add dedicated config for DMA flags

2023-06-19T23:19:22+00:00

The DMA flags field will be useful for users beyond PCI P2P, so upgrade to
its own dedicated config option.

[catalin.marinas@arm.com: use #ifdef CONFIG_NEED_SG_DMA_FLAGS in scatterlist.h]
[catalin.marinas@arm.com: update PCI_P2PDMA dma_flags comment in scatterlist.h]
Link: https://lkml.kernel.org/r/20230612153201.554742-13-catalin.marinas@arm.com
Signed-off-by: Robin Murphy 
Signed-off-by: Catalin Marinas 
Reviewed-by: Christoph Hellwig 
Tested-by: Isaac J. Manjarres 
Cc: Alasdair Kergon 
Cc: Ard Biesheuvel 
Cc: Arnd Bergmann 
Cc: Daniel Vetter 
Cc: Greg Kroah-Hartman 
Cc: Herbert Xu 
Cc: Jerry Snitselaar 
Cc: Joerg Roedel 
Cc: Jonathan Cameron 
Cc: Jonathan Cameron 
Cc: Lars-Peter Clausen 
Cc: Logan Gunthorpe 
Cc: Marc Zyngier 
Cc: Mark Brown 
Cc: Mike Snitzer 
Cc: "Rafael J. Wysocki" 
Cc: Saravana Kannan 
Cc: Vlastimil Babka 
Cc: Will Deacon 
Signed-off-by: Andrew Morton