Commit Graph

9 Commits

Author SHA1 Message Date
Masahiro Yamada
7d2ebbc33d PCI: Use array for .id_table consistently
While 'x' and '&x[0]' are equivalent, most of the PCI drivers use the
former form for the .id_table.

Update some drivers and documentation for consistency.

Link: https://lore.kernel.org/r/20240517120458.1260489-1-masahiroy@kernel.org
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2024-06-07 14:46:12 -05:00
Damien Le Moal
a665b0a93f PCI/portdrv: Use PCI_IRQ_INTX instead of PCI_IRQ_LEGACY
In the PCI Express Port Bus Driver, use the macro PCI_IRQ_INTX instead of
the now deprecated PCI_IRQ_LEGACY macro.

Link: https://lore.kernel.org/r/20240325070944.3600338-3-dlemoal@kernel.org
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2024-04-25 12:53:29 -05:00
Bjorn Helgaas
8a0395578a PCI/portdrv: Use FIELD_GET()
Use FIELD_GET() to remove dependences on the field position, i.e., the
shift value.  No functional change intended.

Link: https://lore.kernel.org/r/20231010204436.1000644-11-helgaas@kernel.org
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
2023-10-24 16:55:45 -05:00
Huacai Chen
62b6dee1b4 PCI/portdrv: Prevent LS7A Bus Master clearing on shutdown
After cc27b735ad ("PCI/portdrv: Turn off PCIe services during shutdown")
we observe hangs during poweroff/reboot on systems with LS7A chipset.

This happens because the portdrv .shutdown() method (pcie_portdrv_remove())
clears PCI_COMMAND_MASTER via pci_disable_device(), which prevents bridges
from forwarding memory or I/O Requests in the upstream direction (PCIe
r6.0, sec 7.5.1.1.3).

LS7A Root Ports have a hardware defect: clearing PCI_COMMAND_MASTER *also*
prevents the bridge from forwarding CPU MMIO requests in the downstream
direction, and these MMIO accesses to devices below the bridge happen even
after .shutdown(), e.g., to print console messages.  LS7A neither forwards
the requests nor sends an unsuccessful completion to the CPU, so the CPU
waits forever, resulting in the hang.

The purpose of .shutdown() is to disable interrupts and DMA from the
device.  PCIe ports may generate interrupts (either MSI/MSI-X or INTx) for
AER, DPC, PME, hotplug, etc., but they never perform DMA except MSI/MSI-X.
Clearing PCI_COMMAND_MASTER effectively disables MSI/MSI-X, but not INTx.

The port service driver .remove() methods clear the interrupt enables in
PCI_ERR_ROOT_COMMAND, PCI_EXP_DPC_CTL, PCI_EXP_SLTCTL, and PCI_EXP_RTCTL,
etc., which disables interrupts regardless of whether they are MSI/MSI-X or
INTx.

Add a pcie_portdrv_shutdown() method that calls all the port service driver
.remove() methods to clear the interrupt enables for each service but does
not clear Bus Mastering on the port itself.

[bhelgaas: commit log]
Link: https://lore.kernel.org/r/20230201043018.778499-2-chenhuacai@loongson.cn
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2023-02-01 12:05:28 -06:00
Bjorn Helgaas
9303050181 Merge branch 'pci/portdrv'
- Squash portdrv_core.c and portdrv_pci.c into portdrv.c to make it easier
  to find things (Bjorn Helgaas)

- Allow AER service only for Root Ports & RCECs so portdrv can successfully
  bind to other devices that have AER but lack MSI (which they don't need
  for AER), which allows power management for those devices (Bjorn Helgaas)

* pci/portdrv:
  PCI/portdrv: Allow AER service only for Root Ports & RCECs
  PCI/portdrv: Unexport pcie_port_service_register(), pcie_port_service_unregister()
  PCI/portdrv: Move private things to portdrv.c
  PCI/portdrv: Squash into portdrv.c
2022-12-10 10:36:34 -06:00
Bjorn Helgaas
d8d2b65a94 PCI/portdrv: Allow AER service only for Root Ports & RCECs
Previously portdrv allowed the AER service for any device with an AER
capability (assuming Linux had control of AER) even though the AER service
driver only attaches to Root Port and RCECs.

Because get_port_device_capability() included AER for non-RP, non-RCEC
devices, we tried to initialize the AER IRQ even though these devices
don't generate AER interrupts.

Intel DG1 and DG2 discrete graphics cards contain a switch leading to a
GPU.  The switch supports AER but not MSI, so initializing an AER IRQ
failed, and portdrv failed to claim the switch port at all.  The GPU itself
could be suspended, but the switch could not be put in a low-power state
because it had no driver.

Don't allow the AER service on non-Root Port, non-Root Complex Event
Collector devices.  This means we won't enable Bus Mastering if the device
doesn't require MSI, the AER service will not appear in sysfs, and the AER
service driver will not bind to the device.

Link: https://lore.kernel.org/r/20221207084105.84947-1-mika.westerberg@linux.intel.com
Link: https://lore.kernel.org/r/20221210002922.1749403-1-helgaas@kernel.org
Based-on-patch-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
2022-12-10 10:26:40 -06:00
Bjorn Helgaas
461a65d7d1 PCI/portdrv: Unexport pcie_port_service_register(), pcie_port_service_unregister()
pcie_port_service_register() and pcie_port_service_unregister() are used
only by the pciehp, aer, dpc, and pme PCIe port service drivers, none of
which can be modules.  Unexport pcie_port_service_register() and
pcie_port_service_unregister().  No functional change intended.

Link: https://lore.kernel.org/r/20221019204127.44463-4-helgaas@kernel.org
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
2022-10-24 14:57:30 -05:00
Bjorn Helgaas
29f193feee PCI/portdrv: Move private things to portdrv.c
Previously several things used by portdrv_core.c and portdrv_pci.c were
shared by defining them in portdrv.h.  Now that portdrv_core.c and
portdrv_pci.c have been squashed, move things that can be private into
portdrv.c.  No functional change intended.

Link: https://lore.kernel.org/r/20221019204127.44463-3-helgaas@kernel.org
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
2022-10-24 14:57:30 -05:00
Bjorn Helgaas
a1ccd3d911 PCI/portdrv: Squash into portdrv.c
Squash portdrv_core.c and portdrv_pci.c into portdrv.c to make it easier to
find things.  The whole thing is less than 1000 lines, and it's a pain to
bounce back and forth between two files.

Several portdrv_core.c functions were non-static because they were
referenced from portdrv_pci.c.  Make them static since they're now all in
portdrv.c.

No functional change intended.

Link: https://lore.kernel.org/r/20221019204127.44463-2-helgaas@kernel.org
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
2022-10-24 14:57:30 -05:00