Commit Graph

981 Commits

Author SHA1 Message Date
Alexei Starovoitov d7bca9199a mm: Introduce vmap_page_range() to map pages in PCI address space
ioremap_page_range() should be used for ranges within vmalloc range only.
The vmalloc ranges are allocated by get_vm_area(). PCI has "resource"
allocator that manages PCI_IOBASE, IO_SPACE_LIMIT address range, hence
introduce vmap_page_range() to be used exclusively to map pages
in PCI address space.

Fixes: 3e49a866c9 ("mm: Enforce VM_IOREMAP flag and range in ioremap_page_range.")
Reported-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Tested-by: Miguel Ojeda <ojeda@kernel.org>
Link: https://lore.kernel.org/bpf/CANiq72ka4rir+RTN2FQoT=Vvprp_Ao-CvoYEkSNqtSY+RZj+AA@mail.gmail.com
2024-03-11 16:58:10 +01:00
Linus Torvalds 4a7571485c pci-v6.8-fixes-3
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Merge tag 'pci-v6.8-fixes-3' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci

Pull pci fixes from Bjorn Helgaas:

 - Keep bridges in D0 if we need to poll downstream devices for PME to
   resolve a v6.6 regression where we failed to enumerate devices below
   bridges put in D3hot by runtime PM, e.g., NVMe drives connected via
   Thunderbolt or USB4 docks (Alex Williamson)

 - Add Siddharth Vadapalli as PCI TI DRA7XX/J721E reviewer

* tag 'pci-v6.8-fixes-3' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci:
  MAINTAINERS: Add Siddharth Vadapalli as PCI TI DRA7XX/J721E reviewer
  PCI: Fix active state requirement in PME polling
2024-02-17 08:06:20 -08:00
Alex Williamson 41044d5360 PCI: Fix active state requirement in PME polling
The commit noted in fixes added a bogus requirement that runtime PM managed
devices need to be in the RPM_ACTIVE state for PME polling.  In fact, only
devices in low power states should be polled.

However there's still a requirement that the device config space must be
accessible, which has implications for both the current state of the polled
device and the parent bridge, when present.  It's not sufficient to assume
the bridge remains in D0 and cases have been observed where the bridge
passes the D0 test, but the PM state indicates RPM_SUSPENDING and config
space of the polled device becomes inaccessible during pci_pme_wakeup().

Therefore, since the bridge is already effectively required to be in the
RPM_ACTIVE state, formalize this in the code and elevate the PM usage count
to maintain the state while polling the subordinate device.

This resolves a regression reported in the bugzilla below where a
Thunderbolt/USB4 hierarchy fails to scan for an attached NVMe endpoint
downstream of a bridge in a D3hot power state.

Link: https://lore.kernel.org/r/20240123185548.1040096-1-alex.williamson@redhat.com
Fixes: d3fcd73603 ("PCI: Fix runtime PM race with PME polling")
Reported-by: Sanath S <sanath.s@amd.com>
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218360
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Tested-by: Sanath S <sanath.s@amd.com>
Reviewed-by: Rafael J. Wysocki <rafael@kernel.org>
Cc: Lukas Wunner <lukas@wunner.de>
Cc: Mika Westerberg <mika.westerberg@linux.intel.com>
2024-02-09 13:03:21 -06:00
Johan Hovold 1e56086415 PCI/ASPM: Fix deadlock when enabling ASPM
A last minute revert in 6.7-final introduced a potential deadlock when
enabling ASPM during probe of Qualcomm PCIe controllers as reported by
lockdep:

  ============================================
  WARNING: possible recursive locking detected
  6.7.0 #40 Not tainted
  --------------------------------------------
  kworker/u16:5/90 is trying to acquire lock:
  ffffacfa78ced000 (pci_bus_sem){++++}-{3:3}, at: pcie_aspm_pm_state_change+0x58/0xdc

              but task is already holding lock:
  ffffacfa78ced000 (pci_bus_sem){++++}-{3:3}, at: pci_walk_bus+0x34/0xbc

              other info that might help us debug this:
   Possible unsafe locking scenario:

         CPU0
         ----
    lock(pci_bus_sem);
    lock(pci_bus_sem);

               *** DEADLOCK ***

  Call trace:
   print_deadlock_bug+0x25c/0x348
   __lock_acquire+0x10a4/0x2064
   lock_acquire+0x1e8/0x318
   down_read+0x60/0x184
   pcie_aspm_pm_state_change+0x58/0xdc
   pci_set_full_power_state+0xa8/0x114
   pci_set_power_state+0xc4/0x120
   qcom_pcie_enable_aspm+0x1c/0x3c [pcie_qcom]
   pci_walk_bus+0x64/0xbc
   qcom_pcie_host_post_init_2_7_0+0x28/0x34 [pcie_qcom]

The deadlock can easily be reproduced on machines like the Lenovo ThinkPad
X13s by adding a delay to increase the race window during asynchronous
probe where another thread can take a write lock.

Add a new pci_set_power_state_locked() and associated helper functions that
can be called with the PCI bus semaphore held to avoid taking the read lock
twice.

Link: https://lore.kernel.org/r/ZZu0qx2cmn7IwTyQ@hovoldconsulting.com
Link: https://lore.kernel.org/r/20240130100243.11011-1-johan+linaro@kernel.org
Fixes: f93e71aea6 ("Revert "PCI/ASPM: Remove pcie_aspm_pm_state_change()"")
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: <stable@vger.kernel.org>	# 6.7
2024-01-31 09:03:51 -06:00
Linus Torvalds db5ccb9eb2 cxl for v6.8
- Add support for parsing the Coherent Device Attribute Table (CDAT)
 
 - Add support for calculating a platform CXL QoS class from CDAT data
 
 - Unify the tracing of EFI CXL Events with native CXL Events.
 
 - Add Get Timestamp support
 
 - Miscellaneous cleanups and fixups
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Merge tag 'cxl-for-6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl

Pull CXL (Compute Express Link) updates from Dan Williams:
 "The bulk of this update is support for enumerating the performance
  capabilities of CXL memory targets and connecting that to a platform
  CXL memory QoS class. Some follow-on work remains to hook up this data
  into core-mm policy, but that is saved for v6.9.

  The next significant update is unifying how CXL event records (things
  like background scrub errors) are processed between so called
  "firmware first" and native error record retrieval. The CXL driver
  handler that processes the record retrieved from the device mailbox is
  now the handler for that same record format coming from an EFI/ACPI
  notification source.

  This also contains miscellaneous feature updates, like Get Timestamp,
  and other fixups.

  Summary:

   - Add support for parsing the Coherent Device Attribute Table (CDAT)

   - Add support for calculating a platform CXL QoS class from CDAT data

   - Unify the tracing of EFI CXL Events with native CXL Events.

   - Add Get Timestamp support

   - Miscellaneous cleanups and fixups"

* tag 'cxl-for-6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl: (41 commits)
  cxl/core: use sysfs_emit() for attr's _show()
  cxl/pci: Register for and process CPER events
  PCI: Introduce cleanup helpers for device reference counts and locks
  acpi/ghes: Process CXL Component Events
  cxl/events: Create a CXL event union
  cxl/events: Separate UUID from event structures
  cxl/events: Remove passing a UUID to known event traces
  cxl/events: Create common event UUID defines
  cxl/events: Promote CXL event structures to a core header
  cxl: Refactor to use __free() for cxl_root allocation in cxl_endpoint_port_probe()
  cxl: Refactor to use __free() for cxl_root allocation in cxl_find_nvdimm_bridge()
  cxl: Fix device reference leak in cxl_port_perf_data_calculate()
  cxl: Convert find_cxl_root() to return a 'struct cxl_root *'
  cxl: Introduce put_cxl_root() helper
  cxl/port: Fix missing target list lock
  cxl/port: Fix decoder initialization when nr_targets > interleave_ways
  cxl/region: fix x9 interleave typo
  cxl/trace: Pass UUID explicitly to event traces
  cxl/region: use %pap format to print resource_size_t
  cxl/region: Add dev_dbg() detail on failure to allocate HPA space
  ...
2024-01-18 16:22:43 -08:00
Linus Torvalds e1aa9df440 pci-v6.8-changes
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Merge tag 'pci-v6.8-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci

Pull pci updates from Bjorn Helgaas:
 "Enumeration:

   - Reserve ECAM so we don't assign it to PCI BARs; this works around
     bugs where BIOS included ECAM in a PNP0A03 host bridge window,
     didn't reserve it via a PNP0C02 motherboard device, and didn't
     allocate space for SR-IOV VF BARs (Bjorn Helgaas)

   - Add MMCONFIG/ECAM debug logging (Bjorn Helgaas)

   - Rename 'MMCONFIG' to 'ECAM' to match spec usage (Bjorn Helgaas)

   - Log device type (Root Port, Switch Port, etc) during enumeration
     (Bjorn Helgaas)

   - Log bridges before downstream devices so the dmesg order is more
     logical (Bjorn Helgaas)

   - Log resource names (BAR 0, VF BAR 0, bridge window, etc)
     consistently instead of a mix of names and "reg 0x10" (Puranjay
     Mohan, Bjorn Helgaas)

   - Fix 64GT/s effective data rate calculation to use 1b/1b encoding
     rather than the 8b/10b or 128b/130b used by lower rates (Ilpo
     Järvinen)

   - Use PCI_HEADER_TYPE_* instead of literals in x86, powerpc, SCSI
     lpfc (Ilpo Järvinen)

   - Clean up open-coded PCIBIOS return code mangling (Ilpo Järvinen)

  Resource management:

   - Restructure pci_dev_for_each_resource() to avoid computing the
     address of an out-of-bounds array element (the bounds check was
     performed later so the element was never actually *read*, but it's
     nicer to avoid even computing an out-of-bounds address) (Andy
     Shevchenko)

  Driver binding:

   - Convert pci-host-common.c platform .remove() callback to
     .remove_new() returning 'void' since it's not useful to return
     error codes here (Uwe Kleine-König)

   - Convert exynos, keystone, kirin from .remove() to .remove_new(),
     which returns void instead of int (Uwe Kleine-König)

   - Drop unused struct pci_driver.node member (Mathias Krause)

  Virtualization:

   - Add ACS quirk for more Zhaoxin Root Ports (LeoLiuoc)

  Error handling:

   - Log AER errors as "Correctable" (not "Corrected") or
     "Uncorrectable" to match spec terminology (Bjorn Helgaas)

   - Decode Requester ID when no error info found instead of printing
     the raw hex value (Bjorn Helgaas)

  Endpoint framework:

   - Use a unique test pattern for each BAR in the pci_endpoint_test to
     make it easier to debug address translation issues (Niklas Cassel)

  Broadcom STB PCIe controller driver:

   - Add DT property "brcm,clkreq-mode" and driver support for different
     CLKREQ# modes to make ASPM L1.x states possible (Jim Quinlan)

  Freescale Layerscape PCIe controller driver:

   - Add suspend/resume support for Layerscape LS1043a and LS1021a,
     including software-managed PME_Turn_Off and transitions between L0,
     L2/L3_Ready Link states (Frank Li)

  MediaTek PCIe controller driver:

   - Clear MSI interrupt status before handler to avoid missing MSIs
     that occur after the handler (qizhong cheng)

  MediaTek PCIe Gen3 controller driver:

   - Update mediatek-gen3 translation window setup to handle MMIO space
     that is not a power of two in size (Jianjun Wang)

  Qualcomm PCIe controller driver:

   - Increase qcom iommu-map maxItems to accommodate SDX55 (five
     entries) and SDM845 (sixteen entries) (Krzysztof Kozlowski)

   - Describe qcom,pcie-sc8180x clocks and resets accurately (Krzysztof
     Kozlowski)

   - Describe qcom,pcie-sm8150 clocks and resets accurately (Krzysztof
     Kozlowski)

   - Correct the qcom "reset-name" property, previously incorrectly
     called "reset-names" (Krzysztof Kozlowski)

   - Document qcom,pcie-sm8650, based on qcom,pcie-sm8550 (Neil
     Armstrong)

  Renesas R-Car PCIe controller driver:

   - Replace of_device.h with explicit of.h include to untangle header
     usage (Rob Herring)

   - Add DT and driver support for optional miniPCIe 1.5v and 3.3v
     regulators on KingFisher (Wolfram Sang)

  SiFive FU740 PCIe controller driver:

   - Convert fu740 CONFIG_PCIE_FU740 dependency from SOC_SIFIVE to
     ARCH_SIFIVE (Conor Dooley)

  Synopsys DesignWare PCIe controller driver:

   - Align iATU mapping for endpoint MSI-X (Niklas Cassel)

   - Drop "host_" prefix from struct dw_pcie_host_ops members (Yoshihiro
     Shimoda)

   - Drop "ep_" prefix from struct dw_pcie_ep_ops members (Yoshihiro
     Shimoda)

   - Rename struct dw_pcie_ep_ops.func_conf_select() to
     .get_dbi_offset() to be more descriptive (Yoshihiro Shimoda)

   - Add Endpoint DBI accessors to encapsulate offset lookups (Yoshihiro
     Shimoda)

  TI J721E PCIe driver:

   - Add j721e DT and driver support for 'num-lanes' for devices that
     support x1, x2, or x4 Links (Matt Ranostay)

   - Add j721e DT compatible strings and driver support for j784s4 (Matt
     Ranostay)

   - Make TI J721E Kconfig depend on ARCH_K3 since the hardware is
     specific to those TI SoC parts (Peter Robinson)

  TI Keystone PCIe controller driver:

   - Hold power management references to all PHYs while enabling them to
     avoid a race when one provides clocks to others (Siddharth
     Vadapalli)

  Xilinx XDMA PCIe controller driver:

   - Remove redundant dev_err(), since platform_get_irq() and
     platform_get_irq_byname() already log errors (Yang Li)

   - Fix uninitialized symbols in xilinx_pl_dma_pcie_setup_irq()
     (Krzysztof Wilczyński)

   - Fix xilinx_pl_dma_pcie_init_irq_domain() error return when
     irq_domain_add_linear() fails (Harshit Mogalapalli)

  MicroSemi Switchtec management driver:

   - Do dma_mrpc cleanup during switchtec_pci_remove() to match its devm
     ioremapping in switchtec_pci_probe(). Previously the cleanup was
     done in stdev_release(), which used stale pointers if stdev->cdev
     happened to be open when the PCI device was removed (Daniel
     Stodden)

  Miscellaneous:

   - Convert interrupt terminology from "legacy" to "INTx" to be more
     specific and match spec terminology (Damien Le Moal)

   - In dw-xdata-pcie, pci_endpoint_test, and vmd, replace usage of
     deprecated ida_simple_*() API with ida_alloc() and ida_free()
     (Christophe JAILLET)"

* tag 'pci-v6.8-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci: (97 commits)
  PCI: Fix kernel-doc issues
  PCI: brcmstb: Configure HW CLKREQ# mode appropriate for downstream device
  dt-bindings: PCI: brcmstb: Add property "brcm,clkreq-mode"
  PCI: mediatek-gen3: Fix translation window size calculation
  PCI: mediatek: Clear interrupt status before dispatching handler
  PCI: keystone: Fix race condition when initializing PHYs
  PCI: xilinx-xdma: Fix error code in xilinx_pl_dma_pcie_init_irq_domain()
  PCI: xilinx-xdma: Fix uninitialized symbols in xilinx_pl_dma_pcie_setup_irq()
  PCI: rcar-gen4: Fix -Wvoid-pointer-to-enum-cast error
  PCI: iproc: Fix -Wvoid-pointer-to-enum-cast warning
  PCI: dwc: Add dw_pcie_ep_{read,write}_dbi[2] helpers
  PCI: dwc: Rename .func_conf_select to .get_dbi_offset in struct dw_pcie_ep_ops
  PCI: dwc: Rename .ep_init to .init in struct dw_pcie_ep_ops
  PCI: dwc: Drop host prefix from struct dw_pcie_host_ops members
  misc: pci_endpoint_test: Use a unique test pattern for each BAR
  PCI: j721e: Make TI J721E depend on ARCH_K3
  PCI: j721e: Add TI J784S4 PCIe configuration
  PCI/AER: Use explicit register sizes for struct members
  PCI/AER: Decode Requester ID when no error info found
  PCI/AER: Use 'Correctable' and 'Uncorrectable' spec terms for errors
  ...
2024-01-17 16:23:17 -08:00
Jakub Kicinski e63c1822ac Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR.

Conflicts:

drivers/net/ethernet/broadcom/bnxt/bnxt.c
  e009b2efb7 ("bnxt_en: Remove mis-applied code from bnxt_cfg_ntp_filters()")
  0f2b214779 ("bnxt_en: Fix compile error without CONFIG_RFS_ACCEL")
https://lore.kernel.org/all/20240105115509.225aa8a2@canb.auug.org.au/

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-01-04 18:06:46 -08:00
Bjorn Helgaas f93e71aea6 Revert "PCI/ASPM: Remove pcie_aspm_pm_state_change()"
This reverts commit 08d0cc5f34.

Michael reported that when attempting to resume from suspend to RAM on ASUS
mini PC PN51-BB757MDE1 (DMI model: MINIPC PN51-E1), 08d0cc5f34
("PCI/ASPM: Remove pcie_aspm_pm_state_change()") caused a 12-second delay
with no output, followed by a reboot.

Workarounds include:

  - Reverting 08d0cc5f34 ("PCI/ASPM: Remove pcie_aspm_pm_state_change()")
  - Booting with "pcie_aspm=off"
  - Booting with "pcie_aspm.policy=performance"
  - "echo 0 | sudo tee /sys/bus/pci/devices/0000:03:00.0/link/l1_aspm"
    before suspending
  - Connecting a USB flash drive

Link: https://lore.kernel.org/r/20240102232550.1751655-1-helgaas@kernel.org
Fixes: 08d0cc5f34 ("PCI/ASPM: Remove pcie_aspm_pm_state_change()")
Reported-by: Michael Schaller <michael@5challer.de>
Link: https://lore.kernel.org/r/76c61361-b8b4-435f-a9f1-32b716763d62@5challer.de
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: <stable@vger.kernel.org>
2024-01-02 17:29:15 -06:00
Dave Jiang 4d07a05397 cxl: Calculate and store PCI link latency for the downstream ports
The latency is calculated by dividing the flit size over the bandwidth. Add
support to retrieve the flit size for the CXL switch device and calculate
the latency of the PCIe link. Cache the latency number with cxl_dport.

Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/170319621931.2212653.6800240203604822886.stgit@djiang5-mobl3
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2023-12-22 14:53:49 -08:00
Puranjay Mohan dc4e6f21c3 PCI: Use resource names in PCI log messages
Use the pci_resource_name() to get the name of the resource and use it
while printing log messages.

[bhelgaas: rename to match struct resource * names, also use names in other
BAR messages]
Link: https://lore.kernel.org/r/20211106112606.192563-3-puranjay12@gmail.com
Signed-off-by: Puranjay Mohan <puranjay12@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2023-12-15 17:28:42 -06:00
Puranjay Mohan 65f8e0beac PCI: Update BAR # and window messages
The PCI log messages print the register offsets at some places and BAR
numbers at other places. There is no uniformity in this logging mechanism.
It would be better to print names than register offsets.

Add a helper function that aids in printing more meaningful information
about the BAR numbers like "VF BAR", "ROM", "bridge window", etc.  This
function can be called while printing PCI log messages.

[bhelgaas: fold in Lukas' static array suggestion from
https://lore.kernel.org/all/20211106115831.GA7452@wunner.de/]
Link: https://lore.kernel.org/r/20211106112606.192563-2-puranjay12@gmail.com
Signed-off-by: Puranjay Mohan <puranjay12@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2023-12-15 17:28:31 -06:00
Ido Schimmel 0a5ef95923 PCI: Add debug print for device ready delay
Currently, the time it took a PCI device to become ready after reset is
only printed if it was longer than 1000ms ('PCI_RESET_WAIT'). However,
for debugging purposes it is useful to know this time even if it was
shorter. For example, with the device I am working on, hardware
engineers asked to verify that it becomes ready on the first try (no
delay).

To that end, add a debug level print that can be enabled using dynamic
debug. Example:

 # echo 1 > /sys/bus/pci/devices/0000\:01\:00.0/reset
 # dmesg -c | grep ready
 # echo "file drivers/pci/pci.c +p" > /sys/kernel/debug/dynamic_debug/control
 # echo 1 > /sys/bus/pci/devices/0000\:01\:00.0/reset
 # dmesg -c | grep ready
 [  396.060335] mlxsw_spectrum4 0000:01:00.0: ready 0ms after bus reset
 # echo "file drivers/pci/pci.c -p" > /sys/kernel/debug/dynamic_debug/control
 # echo 1 > /sys/bus/pci/devices/0000\:01\:00.0/reset
 # dmesg -c | grep ready

Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Petr Machata <petrm@nvidia.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-11-18 17:38:50 +00:00
Bjorn Helgaas 5897c17402 Merge branch 'pci/field-get'
- Use FIELD_GET()/FIELD_PREP() when possible throughout drivers/pci/ (Ilpo
  Järvinen, Bjorn Helgaas)

- Rework DPC control programming for clarity (Ilpo Järvinen)

* pci/field-get:
  PCI/portdrv: Use FIELD_GET()
  PCI/VC: Use FIELD_GET()
  PCI/PTM: Use FIELD_GET()
  PCI/PME: Use FIELD_GET()
  PCI/ATS: Use FIELD_GET()
  PCI/ATS: Show PASID Capability register width in bitmasks
  PCI: Use FIELD_GET() in Sapphire RX 5600 XT Pulse quirk
  PCI: Use FIELD_GET()
  PCI/MSI: Use FIELD_GET/PREP()
  PCI/DPC: Use defines with DPC reason fields
  PCI/DPC: Use defined fields with DPC_CTL register
  PCI/DPC: Use FIELD_GET()
  PCI: hotplug: Use FIELD_GET/PREP()
  PCI: dwc: Use FIELD_GET/PREP()
  PCI: cadence: Use FIELD_GET()
  PCI: Use FIELD_GET() to extract Link Width
  PCI: mvebu: Use FIELD_PREP() with Link Width
  PCI: tegra194: Use FIELD_GET()/FIELD_PREP() with Link Width fields

# Conflicts:
#	drivers/pci/controller/dwc/pcie-tegra194.c
2023-10-28 13:31:05 -05:00
Bjorn Helgaas 65de3fd8f5 Merge branch 'pci/config-errs'
- Simplify config accessor error checking (Ilpo Järvinen)

* pci/config-errs:
  scsi: ipr: Do PCI error checks on own line
  PCI: xgene: Do PCI error check on own line & keep return value
  PCI: Do error check on own line to split long "if" conditions
  atm: iphase: Do PCI error checks on own line
  sh: pci: Do PCI error check on own line
  alpha: Streamline convoluted PCI error handling
2023-10-28 13:31:03 -05:00
Bjorn Helgaas 04e82fa595 PCI: Use FIELD_GET() in Sapphire RX 5600 XT Pulse quirk
Use FIELD_GET() to remove dependences on the field position, i.e., the
shift value.  No functional change intended.

Separate because this isn't as trivial as the other FIELD_GET() changes.

See 907830b0fc ("PCI: Add a REBAR size quirk for Sapphire RX 5600 XT
Pulse")

Link: https://lore.kernel.org/r/20231010204436.1000644-3-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>
Cc: Nirmoy Das <nirmoy.das@amd.com>
2023-10-24 10:54:04 -05:00
Bjorn Helgaas e0f0a16f5f PCI: Use FIELD_GET()
Use FIELD_GET() and FIELD_PREP() to remove dependences on the field
position, i.e., the shift value.  No functional change intended.

Link: https://lore.kernel.org/r/20231010204436.1000644-2-helgaas@kernel.org
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
2023-10-24 10:54:04 -05:00
Ilpo Järvinen d1f9b39da4 PCI: Use FIELD_GET() to extract Link Width
Use FIELD_GET() to extract PCIe Negotiated and Maximum Link Width fields
instead of custom masking and shifting.

Link: https://lore.kernel.org/r/20230919125648.1920-7-ilpo.jarvinen@linux.intel.com
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
[bhelgaas: drop duplicate include of <linux/bitfield.h>]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2023-10-17 20:10:31 -05:00
Ilpo Järvinen d15f18053e PCI: Do error check on own line to split long "if" conditions
Placing PCI error code check inside "if" condition usually results in need
to split lines. Combined with additional conditions the "if" condition
becomes messy.

Convert to the usual error handling pattern with an additional variable to
improve code readability. In addition, reverse the logic in
pci_find_vsec_capability() to get rid of &&.

No functional changes intended.

Link: https://lore.kernel.org/r/20230911125354.25501-5-ilpo.jarvinen@linux.intel.com
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
[bhelgaas: PCI_POSSIBLE_ERROR()]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2023-10-10 16:40:18 -05:00
Ilpo Järvinen 83c088148c PCI: Use PCI_HEADER_TYPE_* instead of literals
Replace literals under drivers/pci/ with PCI_HEADER_TYPE_MASK,
PCI_HEADER_TYPE_NORMAL, and PCI_HEADER_TYPE_MFD.

Also replace !! boolean conversions with FIELD_GET().

Link: https://lore.kernel.org/r/20231003125300.5541-4-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: Wolfram Sang <wsa+renesas@sang-engineering.com> # for Renesas R-Car
2023-10-03 11:55:59 -05:00
Bjorn Helgaas 43cc31da91 Merge branch 'pci/misc'
- Reorder struct pci_dev to avoid holes and reduce size (Christophe
  JAILLET)

- Change pdev->rom_attr_enabled to single bit since it's only a boolean
  value (Christophe JAILLET)

- Use struct_size() in pirq_convert_irt_table() instead of hand-writing it
  (Christophe JAILLET)

- Explicitly include correct DT includes to untangle headers (Rob Herring)

- Fix a DOE race between destroy_work_on_stack() and the stack-allocated
  task->work struct going out of scope in pci_doe() (Ira Weiny)

- Use pci_dev_id() when possible instead of manually composing ID from
  dev->bus->number and dev->devfn (Xiongfeng Wang, Zheng Zengkai)

- Move pci_create_resource_files() declarations to linux/pci.h for alpha
  build warnings (Arnd Bergmann)

- Remove unused hotplug function declarations (Yue Haibing)

- Remove unused mvebu struct mvebu_pcie.busn (Pali Rohár)

- Unexport pcie_port_bus_type (Bjorn Helgaas)

- Remove unnecessary sysfs ID local variable initialization (Bjorn Helgaas)

- Fix BAR value printk formatting to accommodate 32-bit values (Bjorn
  Helgaas)

- Use consistent pointer types for config access syscall get_user() and
  put_user() uses (Bjorn Helgaas)

- Simplify AER_RECOVER_RING_SIZE definition (Bjorn Helgaas)

- Simplify pci_pio_to_address() (Bjorn Helgaas)

- Simplify pci_dev_driver() (Bjorn Helgaas)

- Fix pci_bus_resetable(), pci_slot_resetable() name typos (Bjorn Helgaas)

- Fix code and doc typos and code formatting (Bjorn Helgaas)

- Tidy config space save/restore messages (Bjorn Helgaas)

* pci/misc:
  PCI: Tidy config space save/restore messages
  PCI: Fix code formatting inconsistencies
  PCI: Fix typos in docs and comments
  PCI: Fix pci_bus_resetable(), pci_slot_resetable() name typos
  PCI: Simplify pci_dev_driver()
  PCI: Simplify pci_pio_to_address()
  PCI/AER: Simplify AER_RECOVER_RING_SIZE definition
  PCI: Use consistent put_user() pointer types
  PCI: Fix printk field formatting
  PCI: Remove unnecessary initializations
  PCI: Unexport pcie_port_bus_type
  PCI: mvebu: Remove unused busn member
  PCI: Remove unused function declarations
  PCI/sysfs: Move declarations to linux/pci.h
  PCI/P2PDMA: Use pci_dev_id() to simplify the code
  PCI/IOV: Use pci_dev_id() to simplify the code
  PCI/AER: Use pci_dev_id() to simplify the code
  PCI: apple: Use pci_dev_id() to simplify the code
  PCI/DOE: Fix destroy_work_on_stack() race
  PCI: Explicitly include correct DT includes
  x86/PCI: Use struct_size() in pirq_convert_irt_table()
  PCI: Change pdev->rom_attr_enabled to single bit
  PCI: Reorder pci_dev fields to reduce holes
2023-08-29 11:03:57 -05:00
Bjorn Helgaas 3c298b840c Merge branch 'pci/vpd'
- Ensure device is accessible before VPD access via sysfs (Alex Williamson)

- Ensure device doesn't go to a low-power state while we're polling for PME
  (Alex Williamson)

* pci/vpd:
  PCI: Fix runtime PM race with PME polling
  PCI/VPD: Add runtime power management to sysfs interface
2023-08-29 11:03:50 -05:00
Bjorn Helgaas 95cddeae54 Merge branch 'pci/pm'
- Only read PCI_PM_CTRL register when available, to avoid reading the wrong
  register and corrupting dev->current_state (Feiyang Chen)

* pci/pm:
  PCI/PM: Only read PCI_PM_CTRL register when available
2023-08-29 11:03:49 -05:00
Feiyang Chen 5694ba13b0 PCI/PM: Only read PCI_PM_CTRL register when available
For a device with no Power Management Capability, pci_power_up() previously
returned 0 (success) if the platform was able to put the device in D0,
which led to pci_set_full_power_state() trying to read PCI_PM_CTRL, even
though it doesn't exist.

Since dev->pm_cap == 0 in this case, pci_set_full_power_state() actually
read the wrong register, interpreted it as PCI_PM_CTRL, and corrupted
dev->current_state.  This led to messages like this in some cases:

  pci 0000:01:00.0: Refused to change power state from D3hot to D0

To prevent this, make pci_power_up() always return a negative failure code
if the device lacks a Power Management Capability, even if non-PCI platform
power management has been able to put the device in D0.  The failure will
prevent pci_set_full_power_state() from trying to access PCI_PM_CTRL.

Fixes: e200904b27 ("PCI/PM: Split pci_power_up()")
Link: https://lore.kernel.org/r/20230824013738.1894965-1-chenfeiyang@loongson.cn
Signed-off-by: Feiyang Chen <chenfeiyang@loongson.cn>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: stable@vger.kernel.org	# v5.19+
2023-08-25 16:17:11 -05:00
Bjorn Helgaas 1856d1a036 PCI: Tidy config space save/restore messages
Update config space save/restore debug messages so they line up better.
Previously:

  nvme 0000:05:00.0: saving config space at offset 0x4 (reading 0x20100006)
  nvme 0000:05:00.0: saving config space at offset 0x8 (reading 0x1080200)
  nvme 0000:05:00.0: saving config space at offset 0xc (reading 0x0)

  nvme 0000:05:00.0: restoring config space at offset 0x4 (was 0x0, writing 0x20100006)

Now:

  nvme 0000:05:00.0: save config 0x04: 0x20100006
  nvme 0000:05:00.0: save config 0x08: 0x01080200
  nvme 0000:05:00.0: save config 0x0c: 0x00000000

  nvme 0000:05:00.0: restore config 0x04: 0x00000000 -> 0x20100006

No functional change intended.  Enable these messages by setting
CONFIG_DYNAMIC_DEBUG=y and adding 'dyndbg="file drivers/pci/* +p"'
to kernel parameters.

Link: https://lore.kernel.org/r/20230823191831.476579-1-helgaas@kernel.org
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Rafael J. Wysocki <rafael@kernel.org>
2023-08-25 08:15:47 -05:00
Bjorn Helgaas 86b4ad7d67 PCI: Fix typos in docs and comments
Fix typos in docs and comments.

Link: https://lore.kernel.org/r/20230824193712.542167-11-helgaas@kernel.org
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
2023-08-25 08:15:38 -05:00
Bjorn Helgaas 2b4af4b398 PCI: Fix pci_bus_resetable(), pci_slot_resetable() name typos
Fix typos in the pci_bus_resetable() and pci_slot_resetable() function
names.  No functional change intended.

Link: https://lore.kernel.org/r/20230824193712.542167-10-helgaas@kernel.org
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
2023-08-25 08:15:33 -05:00
Bjorn Helgaas 3b59ca9446 PCI: Simplify pci_pio_to_address()
Simplify pci_pio_to_address() by removing an unnecessary local variable.
No functional change intended.

Link: https://lore.kernel.org/r/20230824193712.542167-8-helgaas@kernel.org
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
2023-08-25 08:15:22 -05:00
Alex Williamson d3fcd73603 PCI: Fix runtime PM race with PME polling
Testing that a device is not currently in a low power state provides no
guarantees that the device is not imminently transitioning to such a state.
Increment the PM usage counter before accessing the device.  Since we don't
wish to wake the device for PME polling, do so only if the device is
already active by using pm_runtime_get_if_active().

Link: https://lore.kernel.org/r/20230803171233.3810944-3-alex.williamson@redhat.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2023-08-11 14:25:58 -05:00
Ilpo Järvinen fb0171a4c0 PCI: Make link retraining use RMW accessors for changing LNKCTL
Don't assume that the device is fully under the control of PCI core.  Use
RMW capability accessors in link retraining which do proper locking to
avoid losing concurrent updates to the register values.

Suggested-by: Lukas Wunner <lukas@wunner.de>
Fixes: 4ec73791a6 ("PCI: Work around Pericom PCIe-to-PCI bridge Retrain Link erratum")
Fixes: 7d715a6c1a ("PCI: add PCI Express ASPM support")
Link: https://lore.kernel.org/r/20230717120503.15276-3-ilpo.jarvinen@linux.intel.com
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: "Rafael J. Wysocki" <rafael@kernel.org>
2023-08-10 11:13:22 -05:00
Bjorn Helgaas 7e229f0e05 Merge branch 'pci/pm'
- Reduce wait time for secondary bus to be ready to speed up resume (Mika
  Westerberg)

- Avoid putting EloPOS E2/S2/H2 (as well as Elo i2) PCIe Ports in D3cold
  (Ondrej Zary)

- Call _REG when transitioning D-states so AML that uses the PCI config
  space OpRegion works, which fixes some ASMedia GPIO controllers (Mario
  Limonciello)

* pci/pm:
  PCI/ACPI: Call _REG when transitioning D-states
  PCI/ACPI: Validate acpi_pci_set_power_state() parameter
  PCI/PM: Avoid putting EloPOS E2/S2/H2 PCIe Ports in D3cold
  PCI/PM: Shorten pci_bridge_wait_for_secondary_bus() wait time for slow links
2023-06-26 12:59:56 -05:00
Bjorn Helgaas 1abb473903 Merge branch 'pci/enumeration'
- Add PCI_EXT_CAP_ID_PL_32GT define (Ben Dooks)

- Propagate firmware node by calling device_set_node() for better
  modularity (Andy Shevchenko)

- Discover Data Link Layer Link Active Reporting earlier so quirks can take
  advantage of it (Maciej W. Rozycki)

- Use cached Data Link Layer Link Active Reporting capability in pciehp,
  powerpc/eeh, and mlx5 (Maciej W. Rozycki)

- Run quirk for devices that require OS to clear Retrain Link earlier, so
  later quirks can rely on it (Maciej W. Rozycki)

- Export pcie_retrain_link() for use outside ASPM (Maciej W. Rozycki)

- Add Data Link Layer Link Active Reporting as another way for
  pcie_retrain_link() to determine the link is up (Maciej W. Rozycki)

- Work around link training failures (especially on the ASMedia ASM2824
  switch) by training first at 2.5GT/s and then attempting higher rates
  (Maciej W. Rozycki)

* pci/enumeration:
  PCI: Add failed link recovery for device reset events
  PCI: Work around PCIe link training failures
  PCI: Use pcie_wait_for_link_status() in pcie_wait_for_link_delay()
  PCI: Add support for polling DLLLA to pcie_retrain_link()
  PCI: Export pcie_retrain_link() for use outside ASPM
  PCI: Export PCIe link retrain timeout
  PCI: Execute quirk_enable_clear_retrain_link() earlier
  PCI/ASPM: Factor out waiting for link training to complete
  PCI/ASPM: Avoid unnecessary pcie_link_state use
  PCI/ASPM: Use distinct local vars in pcie_retrain_link()
  net/mlx5: Rely on dev->link_active_reporting
  powerpc/eeh: Rely on dev->link_active_reporting
  PCI: pciehp: Rely on dev->link_active_reporting
  PCI: Initialize dev->link_active_reporting earlier
  PCI: of: Propagate firmware node by calling device_set_node()
  PCI: Add PCI_EXT_CAP_ID_PL_32GT define

# Conflicts:
#	drivers/pci/pcie/aspm.c
2023-06-26 12:59:56 -05:00
Ondrej Zary 9e30fd26f4 PCI/PM: Avoid putting EloPOS E2/S2/H2 PCIe Ports in D3cold
The quirk for Elo i2 introduced in commit 92597f97a4 ("PCI/PM: Avoid
putting Elo i2 PCIe Ports in D3cold") is also needed by EloPOS E2/S2/H2
which uses the same Continental Z2 board.

Change the quirk to match the board instead of system.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=215715
Link: https://lore.kernel.org/r/20230614074253.22318-1-linux@zary.sk
Signed-off-by: Ondrej Zary <linux@zary.sk>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: stable@vger.kernel.org
2023-06-23 12:27:58 -05:00
Maciej W. Rozycki 08e3ed12ca PCI: Add failed link recovery for device reset events
Request failed link recovery with any upstream PCIe bridge where a device
has not come back after reset within PCI_RESET_WAIT time.  Reset the
polling interval if recovery succeeded, otherwise continue as usual.

[bhelgaas: inline pcie_parent_link_retrain()]
Link: https://lore.kernel.org/r/alpine.DEB.2.21.2306111631050.64925@angie.orcam.me.uk
Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2023-06-20 10:58:53 -05:00
Maciej W. Rozycki a89c82249c PCI: Work around PCIe link training failures
Attempt to handle cases such as with a downstream port of the ASMedia
ASM2824 PCIe switch where link training never completes and the link
continues switching between speeds indefinitely with the data link layer
never reaching the active state.

It has been observed with a downstream port of the ASMedia ASM2824 Gen 3
switch wired to the upstream port of the Pericom PI7C9X2G304 Gen 2 switch,
using a Delock Riser Card PCI Express x1 > 2 x PCIe x1 device, P/N 41433,
wired to a SiFive HiFive Unmatched board.  In this setup the switches
should negotiate a link speed of 5.0GT/s, falling back to 2.5GT/s if
necessary.

Instead the link continues oscillating between the two speeds, at the rate
of 34-35 times per second, with link training reported repeatedly active
~84% of the time.  Limiting the target link speed to 2.5GT/s with the
upstream ASM2824 device makes the two switches communicate correctly.
Removing the speed restriction afterwards makes the two devices switch to
5.0GT/s then.

Make use of these observations and detect the inability to train the link
by checking for the Data Link Layer Link Active status bit being off while
the Link Bandwidth Management Status indicating that hardware has changed
the link speed or width in an attempt to correct unreliable link operation.

Restrict the speed to 2.5GT/s then with the Target Link Speed field,
request a retrain and wait 200ms for the data link to go up.  If this is
successful, lift the restriction, letting the devices negotiate a higher
speed.

Also check for a 2.5GT/s speed restriction the firmware may have already
arranged and lift it too with ports of devices known to continue working
afterwards (currently only ASM2824), that already report their data link
being up.

[bhelgaas: reorder and squash stubs from
https://lore.kernel.org/r/alpine.DEB.2.21.2306111619570.64925@angie.orcam.me.uk
to avoid adding stubs that do nothing]
Link: https://lore.kernel.org/r/alpine.DEB.2.21.2203022037020.56670@angie.orcam.me.uk/
Link: https://source.denx.de/u-boot/u-boot/-/commit/a398a51ccc68
Link: https://lore.kernel.org/r/alpine.DEB.2.21.2305310038540.59226@angie.orcam.me.uk
Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2023-06-20 10:58:53 -05:00
Maciej W. Rozycki 7604bc294c PCI: Use pcie_wait_for_link_status() in pcie_wait_for_link_delay()
Remove a DLLLA status bit polling loop from pcie_wait_for_link_delay() and
call almost identical code in pcie_wait_for_link_status() instead.  This
reduces the lower bound on the polling interval from 10ms to 1ms, possibly
increasing the CPU load on the system in favour to reducing the wait time.

Link: https://lore.kernel.org/r/alpine.DEB.2.21.2306111611170.64925@angie.orcam.me.uk
Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2023-06-20 10:58:53 -05:00
Maciej W. Rozycki 680e9c47a2 PCI: Add support for polling DLLLA to pcie_retrain_link()
Let the caller of pcie_retrain_link() specify whether they want to use the
LT bit or the DLLLA bit of the Link Status Register to determine if link
training has completed.  It is up to the caller to verify whether the use
of the DLLLA bit, the implementation of which is optional, is valid for the
device requested.

Link: https://lore.kernel.org/r/alpine.DEB.2.21.2306110310540.64925@angie.orcam.me.uk
Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2023-06-20 10:58:53 -05:00
Maciej W. Rozycki 37edd87eb6 PCI: Export pcie_retrain_link() for use outside ASPM
Export pcie_retrain_link() for link retrain needs outside ASPM.  Struct
pcie_link_state is local to ASPM and only used by pcie_retrain_link() to
get at the associated PCI device, so change the operand and adjust the lone
call site accordingly.  Document the interface.  No functional change at
this point.

Link: https://lore.kernel.org/r/alpine.DEB.2.21.2306110229010.64925@angie.orcam.me.uk
Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2023-06-20 10:58:53 -05:00
Maciej W. Rozycki 33a176abcc PCI: Export PCIe link retrain timeout
Convert LINK_RETRAIN_TIMEOUT from jiffies to milliseconds, accordingly
rename to PCIE_LINK_RETRAIN_TIMEOUT_MS, and make available via "pci.h" for
the PCI core to use.  Use in pcie_wait_for_link_delay().

Link: https://lore.kernel.org/r/alpine.DEB.2.21.2305310030280.59226@angie.orcam.me.uk
Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2023-06-20 10:58:53 -05:00
Mika Westerberg 7b3ba09feb PCI/PM: Shorten pci_bridge_wait_for_secondary_bus() wait time for slow links
With slow links (<= 5GT/s) active link reporting is not mandatory, so if a
device is disconnected during system sleep we might end up waiting for it
to respond for ~60s, which slows down resume time.

PCIe r6.0, sec 6.6.1, mandates that software must wait for at least 1s
before it can assume a device is broken, so use that minimum requirement
for slow links and bail out if the device doesn't respond within 1s.
However, if the port supports active link reporting we can wait longer as
we do with the fast links.

This should make system resume time faster for slow links as well while
still following the PCIe spec.

While there move the PCI_RESET_WAIT constant into pci.c because it is
not used outside of that file anymore.

Link: https://lore.kernel.org/r/20230425064751.24951-1-mika.westerberg@linux.intel.com
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Lukas Wunner <lukas@wunner.de>
Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
2023-06-06 17:18:49 -05:00
Linus Torvalds 556eb8b791 Driver core changes for 6.4-rc1
Here is the large set of driver core changes for 6.4-rc1.
 
 Once again, a busy development cycle, with lots of changes happening in
 the driver core in the quest to be able to move "struct bus" and "struct
 class" into read-only memory, a task now complete with these changes.
 
 This will make the future rust interactions with the driver core more
 "provably correct" as well as providing more obvious lifetime rules for
 all busses and classes in the kernel.
 
 The changes required for this did touch many individual classes and
 busses as many callbacks were changed to take const * parameters
 instead.  All of these changes have been submitted to the various
 subsystem maintainers, giving them plenty of time to review, and most of
 them actually did so.
 
 Other than those changes, included in here are a small set of other
 things:
   - kobject logging improvements
   - cacheinfo improvements and updates
   - obligatory fw_devlink updates and fixes
   - documentation updates
   - device property cleanups and const * changes
   - firwmare loader dependency fixes.
 
 All of these have been in linux-next for a while with no reported
 problems.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-6.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core updates from Greg KH:
 "Here is the large set of driver core changes for 6.4-rc1.

  Once again, a busy development cycle, with lots of changes happening
  in the driver core in the quest to be able to move "struct bus" and
  "struct class" into read-only memory, a task now complete with these
  changes.

  This will make the future rust interactions with the driver core more
  "provably correct" as well as providing more obvious lifetime rules
  for all busses and classes in the kernel.

  The changes required for this did touch many individual classes and
  busses as many callbacks were changed to take const * parameters
  instead. All of these changes have been submitted to the various
  subsystem maintainers, giving them plenty of time to review, and most
  of them actually did so.

  Other than those changes, included in here are a small set of other
  things:

   - kobject logging improvements

   - cacheinfo improvements and updates

   - obligatory fw_devlink updates and fixes

   - documentation updates

   - device property cleanups and const * changes

   - firwmare loader dependency fixes.

  All of these have been in linux-next for a while with no reported
  problems"

* tag 'driver-core-6.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (120 commits)
  device property: make device_property functions take const device *
  driver core: update comments in device_rename()
  driver core: Don't require dynamic_debug for initcall_debug probe timing
  firmware_loader: rework crypto dependencies
  firmware_loader: Strip off \n from customized path
  zram: fix up permission for the hot_add sysfs file
  cacheinfo: Add use_arch[|_cache]_info field/function
  arch_topology: Remove early cacheinfo error message if -ENOENT
  cacheinfo: Check cache properties are present in DT
  cacheinfo: Check sib_leaf in cache_leaves_are_shared()
  cacheinfo: Allow early level detection when DT/ACPI info is missing/broken
  cacheinfo: Add arm64 early level initializer implementation
  cacheinfo: Add arch specific early level initializer
  tty: make tty_class a static const structure
  driver core: class: remove struct class_interface * from callbacks
  driver core: class: mark the struct class in struct class_interface constant
  driver core: class: make class_register() take a const *
  driver core: class: mark class_release() as taking a const *
  driver core: remove incorrect comment for device_create*
  MIPS: vpe-cmp: remove module owner pointer from struct class usage.
  ...
2023-04-27 11:53:57 -07:00
Bjorn Helgaas 1c03b5bfc5 Merge branch 'pci/resource'
- Add pci_dev_for_each_resource() and pci_bus_for_each_resource() iterators
  to simplify loops (Andy Shevchenko)

* pci/resource:
  EISA: Drop unused pci_bus_for_each_resource() index argument
  PCI: Make pci_bus_for_each_resource() index optional
  PCI: Document pci_bus_for_each_resource()
  PCI: Introduce pci_dev_for_each_resource()
  PCI: Introduce pci_resource_n()
2023-04-20 16:16:34 -05:00
Mika Westerberg e74b2b58ff PCI/PM: Drop pci_bridge_wait_for_secondary_bus() timeout parameter
All callers of pci_bridge_wait_for_secondary_bus() supply a timeout of
PCIE_RESET_READY_POLL_MS, so drop the parameter.  Move the definition of
PCIE_RESET_READY_POLL_MS into pci.c, the only user.

[bhelgaas: extracted from
https://lore.kernel.org/r/20230404052714.51315-3-mika.westerberg@linux.intel.com]
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2023-04-11 17:35:06 -05:00
Andy Shevchenko 02992064bd PCI: Make pci_bus_for_each_resource() index optional
Refactor pci_bus_for_each_resource() in the same way as
pci_dev_for_each_resource(). This allows the index to be hidden inside the
implementation so the caller can omit it when it's not used otherwise.

No functional changes intended.

Link: https://lore.kernel.org/r/20230330162434.35055-6-andriy.shevchenko@linux.intel.com
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Krzysztof Wilczyński <kw@linux.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
2023-04-05 15:10:09 -05:00
Greg Kroah-Hartman 75cff725d9 driver core: bus: mark the struct bus_type for sysfs callbacks as constant
struct bus_type should never be modified in a sysfs callback as there is
nothing in the structure to modify, and frankly, the structure is almost
never used in a sysfs callback, so mark it as constant to allow struct
bus_type to be moved to read-only memory.

Cc: "David S. Miller" <davem@davemloft.net>
Cc: "James E.J. Bottomley" <jejb@linux.ibm.com>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Alexandre Bounine <alex.bou9@gmail.com>
Cc: Alison Schofield <alison.schofield@intel.com>
Cc: Ben Widawsky <bwidawsk@kernel.org>
Cc: Dexuan Cui <decui@microsoft.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Harald Freudenberger <freude@linux.ibm.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Hu Haowen <src.res@email.cn>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Laurentiu Tudor <laurentiu.tudor@nxp.com>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: Stuart Yoder <stuyoder@gmail.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Yanteng Si <siyanteng@loongson.cn>
Acked-by: Ilya Dryomov <idryomov@gmail.com> # rbd
Acked-by: Ira Weiny <ira.weiny@intel.com> # cxl
Reviewed-by: Alex Shi <alexs@kernel.org>
Acked-by: Iwona Winiarska <iwona.winiarska@intel.com>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>	# pci
Acked-by: Wei Liu <wei.liu@kernel.org>
Acked-by: Martin K. Petersen <martin.petersen@oracle.com> # scsi
Link: https://lore.kernel.org/r/20230313182918.1312597-23-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-03-23 13:20:40 +01:00
Linus Torvalds 90ddb3f034 pci-v6.3-changes
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Merge tag 'pci-v6.3-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci

Pull PCI updates from Bjorn Helgaas:
 "Enumeration:

   - Rework portdrv shutdown so it disables interrupts but doesn't
     disable bus mastering, which leads to hangs on Loongson LS7A

   - Add mechanism to prevent Max_Read_Request_Size (MRRS) increases,
     again to avoid hardware issues on Loongson LS7A (and likely other
     devices based on DesignWare IP)

   - Ignore devices with a firmware (DT or ACPI) node that says the
     device is disabled

  Resource management:

   - Distribute spare resources to unconfigured hotplug bridges at
     boot-time (not just when hot-adding such a bridge), which makes
     hot-adding devices to docks work better. Tried this in v6.1 but had
     to revert for regressions, so try again

   - Fix root bus issue that dropped resources that happened to end
     at 0, e.g., [bus 00]

  PCI device hotplug:

   - Remove device locking when marking device as disconnected so this
     doesn't have to wait for concurrent driver bind/unbind to complete

   - Quirk more Qualcomm bridges that don't fully implement the PCIe
     Slot Status 'Command Completed' bit

  Power management:

   - Account for _S0W of the target bridge in acpi_pci_bridge_d3() so we
     don't miss hot-add notifications for USB4 docks, Thunderbolt, etc

  Reset:

   - Observe delay after reset, e.g., resuming from system sleep,
     regardless of whether a bridge can suspend to D3cold at runtime

   - Wait for secondary bus to become ready after a bridge reset

  Virtualization:

   - Avoid FLR on some AMD FCH AHCI adapters where it doesn't work

   - Allow independent IOMMU groups for some Wangxun NICs that prevent
     peer-to-peer transactions but don't advertise an ACS Capability

  Error handling:

   - Configure End-to-End-CRC (ECRC) only if Linux owns the AER
     Capability

   - Remove redundant Device Control Error Reporting Enable in the AER
     service driver since this is already done for all devices during
     enumeration

  ASPM:

   - Add pci_enable_link_state() interface to allow drivers to enable
     ASPM link state

  Endpoint framework:

   - Move dra7xx and tegra194 linkup processing from hard IRQ to
     threaded IRQ handler

   - Add a separate lock for endpoint controller list of endpoint
     function drivers to prevent deadlock in callbacks

   - Pass events from endpoint controller to endpoint function drivers
     via callbacks instead of notifiers

  Synopsys DesignWare eDMA controller driver (acked by Vinod):

   - Fix CPU vs PCI address issues

   - Fix source vs destination address issues

   - Fix issues with interleaved transfer semantics

   - Fix channel count initialization issue (issue still exists in
     several other drivers)

   - Clean up and improve debugfs usage so it will work on platforms
     with several eDMA devices

  Baikal T-1 PCIe controller driver:

   - Set a 64-bit DMA mask

  Freescale i.MX6 PCIe controller driver:

   - Add i.MX8MM, i.MX8MQ, i.MX8MP endpoint mode DT binding and driver
     support

  Intel VMD host bridge driver:

   - Add quirk to configure PCIe ASPM and LTR. This is normally done by
     BIOS, and will be for future products

  Marvell MVEBU PCIe controller driver:

   - Mark this driver as broken in Kconfig since bugs prevent its daily
     usage

  MediaTek MT7621 PCIe controller driver:

   - Delay PHY port initialization to improve boot reliability for ZBT
     WE1326, ZBT WF3526-P, and some Netgear models

  Qualcomm PCIe controller driver:

   - Add MSM8998 DT compatible string

   - Unify MSM8996 and MSM8998 clock orderings

   - Add SM8350 DT binding and driver support

   - Add IPQ8074 Gen3 DT binding and driver support

   - Correct qcom,perst-regs in DT binding

   - Add qcom_pcie_host_deinit() so the PHY is powered off and
     regulators and clocks are disabled on late host-init errors

  Socionext UniPhier Pro5 controller driver:

   - Clean up uniphier-ep reg, clocks, resets, and their names in DT
     binding

  Synopsys DesignWare PCIe controller driver:

   - Restrict coherent DMA mask to 32 bits for MSI, but allow controller
     drivers to set 64-bit streaming DMA mask

   - Add eDMA engine support in both Root Port and Endpoint controllers

  Miscellaneous:

   - Remove MODULE_LICENSE from boolean drivers so they don't look like
     modules so modprobe can complain about them"

* tag 'pci-v6.3-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci: (86 commits)
  PCI: dwc: Add Root Port and Endpoint controller eDMA engine support
  PCI: bt1: Set 64-bit DMA mask
  PCI: dwc: Restrict only coherent DMA mask for MSI address allocation
  dmaengine: dw-edma: Prepare dw_edma_probe() for builtin callers
  dmaengine: dw-edma: Depend on DW_EDMA instead of selecting it
  dmaengine: dw-edma: Add mem-mapped LL-entries support
  PCI: Remove MODULE_LICENSE so boolean drivers don't look like modules
  PCI: hv: Drop duplicate PCI_MSI dependency
  PCI/P2PDMA: Annotate RCU dereference
  PCI/sysfs: Constify struct kobj_type pci_slot_ktype
  PCI: hotplug: Allow marking devices as disconnected during bind/unbind
  PCI: pciehp: Add Qualcomm quirk for Command Completed erratum
  PCI: qcom: Add IPQ8074 Gen3 port support
  dt-bindings: PCI: qcom: Add IPQ8074 Gen3 port
  dt-bindings: PCI: qcom: Sort compatibles alphabetically
  PCI: qcom: Fix host-init error handling
  PCI: qcom: Add SM8350 support
  dt-bindings: PCI: qcom: Add SM8350
  dt-bindings: PCI: qcom-ep: Correct qcom,perst-regs
  dt-bindings: PCI: qcom: Unify MSM8996 and MSM8998 clock order
  ...
2023-02-24 16:51:40 -08:00
Bjorn Helgaas 0b7af1ddcf Merge branch 'pci/reset'
- Always observe reset delay when waking devices from D3cold, e.g., after
  system sleep, regardless of whether we're allowed to runtime-suspend to
  D3cold (Lukas Wunner)

- Unify reset and resume delays to wait for downstream devices after a
  bridge reset (Lukas Wunner)

- Wait for downstream devices after a DPC-induced bridge reset (Lukas
  Wunner)

* pci/reset:
  PCI/DPC: Await readiness of secondary bus after reset
  PCI: Unify delay handling for reset and resume
  PCI/PM: Observe reset delay irrespective of bridge_d3
2023-02-22 13:47:27 -06:00
Bjorn Helgaas a7152be79b Revert "PCI/ASPM: Save L1 PM Substates Capability for suspend/resume"
This reverts commit 4ff116d0d5.

Tasev Nikola and Mark Enriquez reported that resume from suspend was broken
in v6.1-rc1.  Tasev bisected to a47126ec29 ("PCI/PTM: Cache PTM
Capability offset"), but we can't figure out how that could be related.

Mark saw the same symptoms and bisected to 4ff116d0d5 ("PCI/ASPM: Save L1
PM Substates Capability for suspend/resume"), which does have a connection:
it restores L1 Substates configuration while ASPM L1 may be enabled:

  pci_restore_state
    pci_restore_aspm_l1ss_state
      aspm_program_l1ss
        pci_write_config_dword(PCI_L1SS_CTL1, ctl1)         # L1SS restore
    pci_restore_pcie_state
      pcie_capability_write_word(PCI_EXP_LNKCTL, cap[i++])  # L1 restore

which is a problem because PCIe r6.0, sec 5.5.4, requires that:

  If setting either or both of the enable bits for ASPM L1 PM
  Substates, both ports must be configured as described in this
  section while ASPM L1 is disabled.

Separately, Thomas Witt reported that 5e85eba6f5 ("PCI/ASPM: Refactor L1
PM Substates Control Register programming") broke suspend/resume, and it
depends on 4ff116d0d5.

Revert 4ff116d0d5 ("PCI/ASPM: Save L1 PM Substates Capability for
suspend/resume") to fix the resume issue and enable revert of 5e85eba6f5
to fix the issue Thomas reported.

Note that reverting 4ff116d0d5 means L1 Substates config may be lost on
suspend/resume.  As far as we know the system will use more power but will
still *work* correctly.

Fixes: 4ff116d0d5 ("PCI/ASPM: Save L1 PM Substates Capability for suspend/resume")
Link: https://bugzilla.kernel.org/show_bug.cgi?id=216782
Link: https://bugzilla.kernel.org/show_bug.cgi?id=216877
Reported-by: Tasev Nikola <tasev.stefanoska@skynet.be>
Reported-by: Mark Enriquez <enriquezmark36@gmail.com>
Reported-by: Thomas Witt <kernel@witt.link>
Tested-by: Mark Enriquez <enriquezmark36@gmail.com>
Tested-by: Thomas Witt <kernel@witt.link>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: stable@vger.kernel.org	# v6.1+
Cc: Vidya Sagar <vidyas@nvidia.com>
2023-02-10 15:29:53 -06:00
Lukas Wunner 53b54ad074 PCI/DPC: Await readiness of secondary bus after reset
pci_bridge_wait_for_secondary_bus() is called after a Secondary Bus
Reset, but not after a DPC-induced Hot Reset.

As a result, the delays prescribed by PCIe r6.0 sec 6.6.1 are not
observed and devices on the secondary bus may be accessed before
they're ready.

One affected device is Intel's Ponte Vecchio HPC GPU.  It comprises a
PCIe switch whose upstream port is not immediately ready after reset.
Because its config space is restored too early, it remains in
D0uninitialized, its subordinate devices remain inaccessible and DPC
recovery fails with messages such as:

  i915 0000:8c:00.0: can't change power state from D3cold to D0 (config space inaccessible)
  intel_vsec 0000:8e:00.1: can't change power state from D3cold to D0 (config space inaccessible)
  pcieport 0000:89:02.0: AER: device recovery failed

Fix it.

Link: https://lore.kernel.org/r/9f5ff00e1593d8d9a4b452398b98aa14d23fca11.1673769517.git.lukas@wunner.de
Tested-by: Ravi Kishore Koppuravuri <ravi.kishore.koppuravuri@intel.com>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Cc: stable@vger.kernel.org
2023-02-09 12:46:15 -06:00
Lukas Wunner ac91e69805 PCI: Unify delay handling for reset and resume
Sheng Bi reports that pci_bridge_secondary_bus_reset() may fail to wait
for devices on the secondary bus to become accessible after reset:

Although it does call pci_dev_wait(), it erroneously passes the bridge's
pci_dev rather than that of a child.  The bridge of course is always
accessible while its secondary bus is reset, so pci_dev_wait() returns
immediately.

Sheng Bi proposes introducing a new pci_bridge_secondary_bus_wait()
function which is called from pci_bridge_secondary_bus_reset():

https://lore.kernel.org/linux-pci/20220523171517.32407-1-windy.bi.enflame@gmail.com/

However we already have pci_bridge_wait_for_secondary_bus() which does
almost exactly what we need.  So far it's only called on resume from
D3cold (which implies a Fundamental Reset per PCIe r6.0 sec 5.8).
Re-using it for Secondary Bus Resets is a leaner and more rational
approach than introducing a new function.

That only requires a few minor tweaks:

- Amend pci_bridge_wait_for_secondary_bus() to await accessibility of
  the first device on the secondary bus by calling pci_dev_wait() after
  performing the prescribed delays.  pci_dev_wait() needs two parameters,
  a reset reason and a timeout, which callers must now pass to
  pci_bridge_wait_for_secondary_bus().  The timeout is 1 sec for resume
  (PCIe r6.0 sec 6.6.1) and 60 sec for reset (commit 821cdad5c4 ("PCI:
  Wait up to 60 seconds for device to become ready after FLR")).
  Introduce a PCI_RESET_WAIT macro for the 1 sec timeout.

- Amend pci_bridge_wait_for_secondary_bus() to return 0 on success or
  -ENOTTY on error for consumption by pci_bridge_secondary_bus_reset().

- Drop an unnecessary 1 sec delay from pci_reset_secondary_bus() which
  is now performed by pci_bridge_wait_for_secondary_bus().  A static
  delay this long is only necessary for Conventional PCI, so modern
  PCIe systems benefit from shorter reset times as a side effect.

Fixes: 6b2f1351af ("PCI: Wait for device to become ready after secondary bus reset")
Link: https://lore.kernel.org/r/da77c92796b99ec568bd070cbe4725074a117038.1673769517.git.lukas@wunner.de
Reported-by: Sheng Bi <windy.bi.enflame@gmail.com>
Tested-by: Ravi Kishore Koppuravuri <ravi.kishore.koppuravuri@intel.com>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Cc: stable@vger.kernel.org # v4.17+
2023-02-07 11:54:03 -06:00
Lukas Wunner 8ef0217227 PCI/PM: Observe reset delay irrespective of bridge_d3
If a PCI bridge is suspended to D3cold upon entering system sleep,
resuming it entails a Fundamental Reset per PCIe r6.0 sec 5.8.

The delay prescribed after a Fundamental Reset in PCIe r6.0 sec 6.6.1
is sought to be observed by:

  pci_pm_resume_noirq()
    pci_pm_bridge_power_up_actions()
      pci_bridge_wait_for_secondary_bus()

However, pci_bridge_wait_for_secondary_bus() bails out if the bridge_d3
flag is not set.  That flag indicates whether a bridge is allowed to
suspend to D3cold at *runtime*.

Hence *no* delay is observed on resume from system sleep if runtime
D3cold is forbidden.  That doesn't make any sense, so drop the bridge_d3
check from pci_bridge_wait_for_secondary_bus().

The purpose of the bridge_d3 check was probably to avoid delays if a
bridge remained in D0 during suspend.  However the sole caller of
pci_bridge_wait_for_secondary_bus(), pci_pm_bridge_power_up_actions(),
is only invoked if the previous power state was D3cold.  Hence the
additional bridge_d3 check seems superfluous.

Fixes: ad9001f2f4 ("PCI/PM: Add missing link delays required by the PCIe spec")
Link: https://lore.kernel.org/r/eb37fa345285ec8bacabbf06b020b803f77bdd3d.1673769517.git.lukas@wunner.de
Tested-by: Ravi Kishore Koppuravuri <ravi.kishore.koppuravuri@intel.com>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Cc: stable@vger.kernel.org # v5.5+
2023-02-07 11:54:03 -06:00