Pull PCIe Link Encryption and Device Authentication from Dan Williams:
"New PCI infrastructure and one architecture implementation for PCIe
link encryption establishment via platform firmware services.
This work is the result of multiple vendors coming to consensus on
some core infrastructure (thanks Alexey, Yilun, and Aneesh!), and
three vendor implementations, although only one is included in this
pull. The PCI core changes have an ack from Bjorn, the crypto/ccp/
changes have an ack from Tom, and the iommu/amd/ changes have an ack
from Joerg.
PCIe link encryption is made possible by the soup of acronyms
mentioned in the shortlog below. Link Integrity and Data Encryption
(IDE) is a protocol for installing keys in the transmitter and
receiver at each end of a link. That protocol is transported over Data
Object Exchange (DOE) mailboxes using PCI configuration requests.
The aspect that makes this a "platform firmware service" is that the
key provisioning and protocol is coordinated through a Trusted
Execution Envrionment (TEE) Security Manager (TSM). That is either
firmware running in a coprocessor (AMD SEV-TIO), or quasi-hypervisor
software (Intel TDX Connect / ARM CCA) running in a protected CPU
mode.
Now, the only reason to ask a TSM to run this protocol and install the
keys rather than have a Linux driver do the same is so that later, a
confidential VM can ask the TSM directly "can you certify this
device?".
That precludes host Linux from provisioning its own keys, because host
Linux is outside the trust domain for the VM. It also turns out that
all architectures, save for one, do not publish a mechanism for an OS
to establish keys in the root port. So "TSM-established link
encryption" is the only cross-architecture path for this capability
for the foreseeable future.
This unblocks the other arch implementations to follow in v6.20/v7.0,
once they clear some other dependencies, and it unblocks the next
phase of work to implement the end-to-end flow of confidential device
assignment. The PCIe specification calls this end-to-end flow Trusted
Execution Environment (TEE) Device Interface Security Protocol
(TDISP).
In the meantime, Linux gets a link encryption facility which has
practical benefits along the same lines as memory encryption. It
authenticates devices via certificates and may protect against
interposer attacks trying to capture clear-text PCIe traffic.
Summary:
- Introduce the PCI/TSM core for the coordination of device
authentication, link encryption and establishment (IDE), and later
management of the device security operational states (TDISP).
Notify the new TSM core layer of PCI device arrival and departure
- Add a low level TSM driver for the link encryption establishment
capabilities of the AMD SEV-TIO architecture
- Add a library of helpers TSM drivers to use for IDE establishment
and the DOE transport
- Add skeleton support for 'bind' and 'guest_request' operations in
support of TDISP"
* tag 'tsm-for-6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/devsec/tsm: (23 commits)
crypto/ccp: Fix CONFIG_PCI=n build
virt: Fix Kconfig warning when selecting TSM without VIRT_DRIVERS
crypto/ccp: Implement SEV-TIO PCIe IDE (phase1)
iommu/amd: Report SEV-TIO support
psp-sev: Assign numbers to all status codes and add new
ccp: Make snp_reclaim_pages and __sev_do_cmd_locked public
PCI/TSM: Add 'dsm' and 'bound' attributes for dependent functions
PCI/TSM: Add pci_tsm_guest_req() for managing TDIs
PCI/TSM: Add pci_tsm_bind() helper for instantiating TDIs
PCI/IDE: Initialize an ID for all IDE streams
PCI/IDE: Add Address Association Register setup for downstream MMIO
resource: Introduce resource_assigned() for discerning active resources
PCI/TSM: Drop stub for pci_tsm_doe_transfer()
drivers/virt: Drop VIRT_DRIVERS build dependency
PCI/TSM: Report active IDE streams
PCI/IDE: Report available IDE streams
PCI/IDE: Add IDE establishment helpers
PCI: Establish document for PCI host bridge sysfs attributes
PCI: Add PCIe Device 3 Extended Capability enumeration
PCI/TSM: Establish Secure Sessions and Link Encryption
...
Pull PCI updates from Bjorn Helgaas:
"Enumeration:
- Enable host bridge emulation for PCI_DOMAINS_GENERIC platforms (Dan
Williams)
- Switch vmd from custom domain number allocator to the common
allocator to prevent a potential race with new non-VMD buses (Dan
Williams)
- Enable Precision Time Measurement (PTM) only if device advertises
support for a relevant role, to prevent invalid PTM Requests that
cause ACS violations that are reported as AER Uncorrectable
Non-Fatal errors (Mika Westerberg)
Resource management:
- Prevent resource tree corruption when BAR resize fails (Ilpo
Järvinen)
- Restore BARs to the original size if a BAR resize fails (Ilpo
Järvinen)
- Remove BAR release from BAR resize attempts by the xe, i915, and
amdgpu drivers so the PCI core can restore BARs if the resize fails
(Ilpo Järvinen)
- Move Resizable BAR code to rebar.c (Ilpo Järvinen)
- Add pci_rebar_size_supported() and use it in i915 and xe (Ilpo
Järvinen)
- Add pci_rebar_get_max_size() and use it in xe and amdgpu (Ilpo
Järvinen)
Power management and error handling:
- For drivers using PCI legacy suspend, save config state at suspend
so that state (not any earlier state from enumeration, probe, or
error recovery) will be restored when resuming (Lukas Wunner)
- For devices with no driver or a driver that lacks power management,
save config state at hibernate so that state (not any earlier state
from enumeration, probe, or error recovery) will be restored when
resuming (Lukas Wunner)
- Save device config space on device addition, before driver binding,
so error recovery works more reliably (Lukas Wunner)
- Drop pci_save_state() from several drivers that no longer need it
since the PCI core always does it and pci_restore_state() no longer
invalidates the saved state (Lukas Wunner)
- Document use of pci_save_state() by drivers to capture the state
they want restored during error recovery (Lukas Wunner)
Power control:
- Add a struct pci_ops.assert_perst() function pointer to
assert/deassert PCIe PERST# and implement it for the qcom driver
(Krishna Chaitanya Chundru)
- Add DT binding and pwrctrl driver for the Toshiba TC9563 PCIe
switch, which must be held in reset after poweron so the pwrctrl
driver can configure the switch via I2C before bringing up the
links (Krishna Chaitanya Chundru)
Endpoint framework:
- Convert the endpoint doorbell test to use a threaded IRQ to fix a
'sleeping while atomic' issue (Bhanu Seshu Kumar Valluri)
- Add endpoint VNTB MSI doorbell support to reduce latency between
host and endpoint (Frank Li)
New native PCIe controller drivers:
- Add CIX Sky1 host controller DT binding and driver (Hans Zhang)
- Add NXP S32G host controller DT binding and driver (Vincent
Guittot)
- Add Renesas RZ/G3S host controller DT binding and driver (Claudiu
Beznea)
- Add SpacemiT K1 host controller DT binding and driver (Alex Elder)
Amlogic Meson PCIe controller driver:
- Update DT binding to name DBI region 'dbi', not 'elbi', and update
driver to support both (Manivannan Sadhasivam)
Apple PCIe controller driver:
- Move struct pci_host_bridge allocation from pci_host_common_init()
to callers, which significantly simplifies pcie-apple (Marc
Zyngier)
Broadcom STB PCIe controller driver:
- Disable advertising ASPM L0s support correctly (Jim Quinlan)
- Add a panic/die handler to print diagnostic info in case PCIe
caused an unrecoverable abort (Jim Quinlan)
Cadence PCIe controller driver:
- Add module support for Cadence platform host and endpoint
controller driver (Manikandan K Pillai)
- Split headers into 'legacy' (LGA) and 'high perf' (HPA) to prepare
for new CIX Sky1 driver (Manikandan K Pillai)
MediaTek PCIe controller driver:
- Convert DT binding to YAML schema (Christian Marangi)
- Add Airoha AN7583 DT compatible and driver support (Christian
Marangi)
Qualcomm PCIe controller driver:
- Add Qualcomm Kaanapali to SM8550 DT binding (Qiang Yu)
- Add required 'power-domains' and 'resets' to qcom sa8775p, sc7280,
sc8280xp, sm8150, sm8250, sm8350, sm8450, sm8550, x1e80100 DT
schemas (Krzysztof Kozlowski)
- Look up OPP using both frequency and data rate (not just frequency)
so RPMh votes can account for both (Krishna Chaitanya Chundru)
Rockchip DesignWare PCIe controller driver:
- Add Rockchip RK3528 compatible strings in DT binding (Yao Zi)
STMicroelectronics STM32MP25 PCIe controller driver:
- Fix a race between link training and endpoint register
initialization (Christian Bruel)
- Align endpoint allocations to match the ATU requirements (Christian
Bruel)
Synopsys DesignWare PCIe controller driver:
- Clear L1 PM Substate Capability 'Supported' bits unless glue driver
says it's supported, which prevents users from enabling non-working
L1SS. Currently only qcom and tegra194 support L1SS (Bjorn Helgaas)
- Remove now-superfluous L1SS disable code from tegra194 (Bjorn
Helgaas)
- Configure L1SS support in dw-rockchip when DT says
'supports-clkreq' (Shawn Lin)
TI Keystone PCIe controller driver:
- Fail the probe instead of silently succeeding if ks_pcie_of_data
didn't specify Root Complex or Endpoint mode (Siddharth Vadapalli)
- Make keystone buildable as a loadable module, except on ARM32 where
hook_fault_code() is __init (Siddharth Vadapalli)"
* tag 'pci-v6.19-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci: (100 commits)
MAINTAINERS: Add Manivannan Sadhasivam as PCI/pwrctrl maintainer
MAINTAINERS: Add CIX Sky1 PCIe controller driver maintainer
PCI: sky1: Add PCIe host support for CIX Sky1
dt-bindings: PCI: Add CIX Sky1 PCIe Root Complex bindings
PCI: cadence: Add support for High Perf Architecture (HPA) controller
MAINTAINERS: Add NXP S32G PCIe controller driver maintainer
PCI: s32g: Add NXP S32G PCIe controller driver (RC)
PCI: dwc: Add register and bitfield definitions
dt-bindings: PCI: s32g: Add NXP S32G PCIe controller
PCI: Add Renesas RZ/G3S host controller driver
PCI: host-generic: Move bridge allocation outside of pci_host_common_init()
dt-bindings: PCI: Add Renesas RZ/G3S PCIe controller binding
PCI: Validate pci_rebar_size_supported() input
Documentation: PCI: Amend error recovery doc with pci_save_state() rules
treewide: Drop pci_save_state() after pci_restore_state()
PCI/ERR: Ensure error recoverability at all times
PCI/PM: Stop needlessly clearing state_saved on enumeration and thaw
PCI/PM: Reinstate clearing state_saved in legacy and !PM codepaths
PCI: dw-rockchip: Configure L1SS support
PCI: tegra194: Remove unnecessary L1SS disable code
...
- Use max() instead of max_t() to ease static analysis (David Laight)
- Add Manivannan Sadhasivam as PCI/pwrctrl maintainer (Bartosz Golaszewski)
* pci/misc:
MAINTAINERS: Add Manivannan Sadhasivam as PCI/pwrctrl maintainer
PCI: Use max() instead of max_t() to ease static analysis
- For drivers using PCI legacy suspend, save config state at suspend so
that state (not any earlier state from enumeration, probe, or error
recovery) will be restored when resuming (Lukas Wunner)
- For devices with no driver or a driver that lacks PM, save config state
at hibernate so that state (not any earlier state from enumeration,
probe, or error recovery) will be restored when resuming (Lukas Wunner)
- Save device config space on device addition, before driver binding, so
error recovery works more reliably (Lukas Wunner)
- Drop pci_save_state() from several drivers that no longer need it since
the PCI core always does it and pci_restore_state() no longer invalidates
the saved state (Lukas Wunner)
- Document use of pci_save_state() by drivers to capture the state they
want restored during error recovery (Lukas Wunner)
* pci/err:
Documentation: PCI: Amend error recovery doc with pci_save_state() rules
treewide: Drop pci_save_state() after pci_restore_state()
PCI/ERR: Ensure error recoverability at all times
PCI/PM: Stop needlessly clearing state_saved on enumeration and thaw
PCI/PM: Reinstate clearing state_saved in legacy and !PM codepaths
The state_saved flag tells the PCI core whether a driver assumes
responsibility to save Config Space and put the device into a low power
state on suspend.
The flag is currently initialized to false on enumeration, even though it
already is false (because struct pci_dev is zeroed by kzalloc()) and even
though it is set to false before commencing the suspend sequence (the only
code path where it's relevant).
The flag is also set to false in pci_pm_thaw(), i.e. on resume, when it's
no longer relevant.
Drop these two superfluous flag assignments for simplicity.
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rafael J. Wysocki (Intel) <rafael@kernel.org>
Link: https://patch.msgid.link/fd167945bd7852e1ca08cd4b202130659eea2c2f.1763483367.git.lukas@wunner.de
In this code:
used_buses = max_t(unsigned int, available_buses,
pci_hotplug_bus_size - 1);
max_t() casts the 'unsigned long' pci_hotplug_bus_size (either 32 or 64
bits) to 'unsigned int' (32 bits) result type, so there's a potential of
discarding significant bits.
Instead, use max(a, b), which casts 'unsigned int' to 'unsigned long' and
cannot discard significant bits.
In this case, pci_hotplug_bus_size is constrained to <= 0xff by pci_setup()
so this doesn't fix a bug, but it makes static analysis easier.
Signed-off-by: David Laight <david.laight.linux@gmail.com>
[bhelgaas: commit log]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Link: https://patch.msgid.link/20251119224140.8616-26-david.laight.linux@gmail.com
Pull pci fixes from Bjorn Helgaas:
- Cache the ASPM L0s/L1 Supported bits early so quirks can override
them if necessary (Bjorn Helgaas)
- Add quirks for PA Semi and Freescale Root Ports and a HiSilicon Wi-Fi
device that are reported to have broken L0s and L1 (Shawn Lin, Bjorn
Helgaas)
* tag 'pci-v6.18-fixes-5' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci:
PCI/ASPM: Avoid L0s and L1 on Hi1105 [19e5:1105] Wi-Fi
PCI/ASPM: Avoid L0s and L1 on PA Semi [1959:a002] Root Ports
PCI/ASPM: Avoid L0s and L1 on Freescale [1957:0451] Root Ports
PCI/ASPM: Convert quirks to override advertised link states
PCI/ASPM: Add pcie_aspm_remove_cap() to override advertised link states
PCI/ASPM: Cache L0s/L1 Supported so advertised link states can be overridden
Defective devices sometimes advertise support for ASPM L0s or L1 states
even if they don't work correctly.
Cache the L0s Supported and L1 Supported bits early in enumeration so
HEADER quirks can override the ASPM states advertised in Link Capabilities
before pcie_aspm_cap_init() enables ASPM.
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Tested-by: Shawn Lin <shawn.lin@rock-chips.com>
Reviewed-by: Lukas Wunner <lukas@wunner.de>
Link: https://patch.msgid.link/20251110222929.2140564-2-helgaas@kernel.org
The limited number of link-encryption (IDE) streams that a given set of
host bridges supports is a platform specific detail. Provide
pci_ide_init_nr_streams() as a generic facility for either platform TSM
drivers, or PCI core native IDE, to report the number available streams.
After invoking pci_ide_init_nr_streams() an "available_secure_streams"
attribute appears in PCI host bridge sysfs to convey that count.
Introduce a device-type, @pci_host_bridge_type, now that both a release
method and sysfs attribute groups are being specified for all 'struct
pci_host_bridge' instances.
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Lukas Wunner <lukas@wunner.de>
Cc: Samuel Ortiz <sameo@rivosinc.com>
Cc: Alexey Kardashevskiy <aik@amd.com>
Cc: Xu Yilun <yilun.xu@linux.intel.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Link: https://patch.msgid.link/20251031212902.2256310-9-dan.j.williams@intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
There are two components to establishing an encrypted link, provisioning
the stream in Partner Port config-space, and programming the keys into
the link layer via IDE_KM (IDE Key Management). This new library,
drivers/pci/ide.c, enables the former. IDE_KM, via a TSM low-level
driver, is saved for later.
With the platform TSM implementations of SEV-TIO and TDX Connect in mind
this library abstracts small differences in those implementations. For
example, TDX Connect handles Root Port register setup while SEV-TIO
expects System Software to update the Root Port registers. This is the
rationale for fine-grained 'setup' + 'enable' verbs.
The other design detail for TSM-coordinated IDE establishment is that
the TSM may manage allocation of Stream IDs, this is why the Stream ID
value is passed in to pci_ide_stream_setup().
The flow is:
pci_ide_stream_alloc():
Allocate a Selective IDE Stream Register Block in each Partner Port
(Endpoint + Root Port), and reserve a host bridge / platform stream
slot. Gather Partner Port specific stream settings like Requester ID.
pci_ide_stream_register():
Publish the stream in sysfs after allocating a Stream ID. In the TSM
case the TSM allocates the Stream ID for the Partner Port pair.
pci_ide_stream_setup():
Program the stream settings to a Partner Port. Caller is responsible
for optionally calling this for the Root Port as well if the TSM
implementation requires it.
pci_ide_stream_enable():
Enable the stream after IDE_KM.
In support of system administrators auditing where platform, Root Port,
and Endpoint IDE stream resources are being spent, the allocated stream
is reflected as a symlink from the host bridge to the endpoint with the
name:
stream%d.%d.%d
Where the tuple of integers reflects the allocated platform, Root Port,
and Endpoint stream index (Selective IDE Stream Register Block) values.
Thanks to Wu Hao for a draft implementation of this infrastructure.
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Lukas Wunner <lukas@wunner.de>
Cc: Samuel Ortiz <sameo@rivosinc.com>
Co-developed-by: Alexey Kardashevskiy <aik@amd.com>
Signed-off-by: Alexey Kardashevskiy <aik@amd.com>
Co-developed-by: Xu Yilun <yilun.xu@linux.intel.com>
Signed-off-by: Xu Yilun <yilun.xu@linux.intel.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Link: https://patch.msgid.link/20251031212902.2256310-8-dan.j.williams@intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
The PCIe 7.0 specification, section 11, defines the Trusted Execution
Environment (TEE) Device Interface Security Protocol (TDISP). This
protocol definition builds upon Component Measurement and Authentication
(CMA), and link Integrity and Data Encryption (IDE). It adds support for
assigning devices (PCI physical or virtual function) to a confidential VM
such that the assigned device is enabled to access guest private memory
protected by technologies like Intel TDX, AMD SEV-SNP, RISCV COVE, or ARM
CCA.
The "TSM" (TEE Security Manager) is a concept in the TDISP specification
of an agent that mediates between a "DSM" (Device Security Manager) and
system software in both a VMM and a confidential VM. A VMM uses TSM ABIs
to setup link security and assign devices. A confidential VM uses TSM
ABIs to transition an assigned device into the TDISP "RUN" state and
validate its configuration. From a Linux perspective the TSM abstracts
many of the details of TDISP, IDE, and CMA. Some of those details leak
through at times, but for the most part TDISP is an internal
implementation detail of the TSM.
CONFIG_PCI_TSM adds an "authenticated" attribute and "tsm/" subdirectory
to pci-sysfs. Consider that the TSM driver may itself be a PCI driver.
Userspace can watch for the arrival of a "TSM" device,
/sys/class/tsm/tsm0/uevent KOBJ_CHANGE, to know when the PCI core has
initialized TSM services.
The operations that can be executed against a PCI device are split into
two mutually exclusive operation sets, "Link" and "Security" (struct
pci_tsm_{link,security}_ops). The "Link" operations manage physical link
security properties and communication with the device's Device Security
Manager firmware. These are the host side operations in TDISP. The
"Security" operations coordinate the security state of the assigned
virtual device (TDI). These are the guest side operations in TDISP.
Only "link" (Secure Session and physical Link Encryption) operations are
defined at this stage. There are placeholders for the device security
(Trusted Computing Base entry / exit) operations.
The locking allows for multiple devices to be executing commands
simultaneously, one outstanding command per-device and an rwsem
synchronizes the implementation relative to TSM registration/unregistration
events.
Thanks to Wu Hao for his work on an early draft of this support.
Cc: Lukas Wunner <lukas@wunner.de>
Cc: Samuel Ortiz <sameo@rivosinc.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Reviewed-by: Alexey Kardashevskiy <aik@amd.com>
Co-developed-by: Xu Yilun <yilun.xu@linux.intel.com>
Signed-off-by: Xu Yilun <yilun.xu@linux.intel.com>
Link: https://patch.msgid.link/20251031212902.2256310-5-dan.j.williams@intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Link encryption is a new PCIe feature enumerated by "PCIe r7.0 section
7.9.26 IDE Extended Capability".
It is both a standalone port + endpoint capability, and a building block
for the security protocol defined by "PCIe r7.0 section 11 TEE Device
Interface Security Protocol (TDISP)". That protocol coordinates device
security setup between a platform TSM (TEE Security Manager) and a
device DSM (Device Security Manager). While the platform TSM can
allocate resources like Stream ID and manage keys, it still requires
system software to manage the IDE capability register block.
Add register definitions and basic enumeration in preparation for
Selective IDE Stream establishment. A follow on change selects the new
CONFIG_PCI_IDE symbol. Note that while the IDE specification defines
both a point-to-point "Link Stream" and a Root Port to endpoint
"Selective Stream", only "Selective Stream" is considered for Linux as
that is the predominant mode expected by Trusted Execution Environment
Security Managers (TSMs), and it is the security model that limits the
number of PCI components within the TCB in a PCIe topology with
switches.
Co-developed-by: Alexey Kardashevskiy <aik@amd.com>
Signed-off-by: Alexey Kardashevskiy <aik@amd.com>
Co-developed-by: Xu Yilun <yilun.xu@linux.intel.com>
Signed-off-by: Xu Yilun <yilun.xu@linux.intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Alexey Kardashevskiy <aik@amd.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@kernel.org>
Link: https://patch.msgid.link/20251031212902.2256310-3-dan.j.williams@intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
The ability to emulate a host bridge is useful not only for hardware PCI
controllers like CONFIG_VMD, or virtual PCI controllers like
CONFIG_PCI_HYPERV, but also for test and development scenarios like
CONFIG_SAMPLES_DEVSEC [1].
One stumbling block for defining CONFIG_SAMPLES_DEVSEC, a sample
implementation of a platform TSM for PCI Device Security, is the need to
accommodate PCI_DOMAINS_GENERIC architectures alongside x86 [2].
In support of supplementing the existing CONFIG_PCI_BRIDGE_EMUL
infrastructure for host bridges:
* Introduce pci_bus_find_emul_domain_nr() as a common way to find a free
PCI domain number whether that is to reuse the existing dynamic
allocation code in the !ACPI case, or to assign an unused domain above
the last ACPI segment.
* Convert pci-hyperv to the new allocator so that the PCI core can
unconditionally assume that bridge->domain_nr != PCI_DOMAIN_NR_NOT_SET
is the dynamically allocated case.
A follow on patch can also convert vmd to the new scheme. Currently vmd is
limited to CONFIG_PCI_DOMAINS_GENERIC=n (x86) so, unlike pci-hyperv, it
does not immediately conflict with this new pci_bus_find_emul_domain_nr()
mechanism.
Link: http://lore.kernel.org/174107249038.1288555.12362100502109498455.stgit@dwillia2-xfh.jf.intel.com [1]
Reported-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Closes: http://lore.kernel.org/20250311144601.145736-3-suzuki.poulose@arm.com [2]
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Tested-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Tested-by: Michael Kelley <mhklinux@outlook.com>
Reviewed-by: Michael Kelley <mhklinux@outlook.com>
Cc: Lorenzo Pieralisi <lpieralisi@kernel.org>
Cc: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Cc: Rob Herring <robh@kernel.org>
Cc: K. Y. Srinivasan <kys@microsoft.com>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Wei Liu <wei.liu@kernel.org>
Cc: Dexuan Cui <decui@microsoft.com>
Link: https://patch.msgid.link/20251024224622.1470555-2-dan.j.williams@intel.com
The commit a43ac325c7 ("PCI: Set up bridge resources earlier") moved
bridge window resources set up earlier than before. The change was
necessary to support another change that got pulled on the last minute
due to breaking s390 and other systems.
The presence of valid bridge window resources earlier than before allows
pci_assign_unassigned_root_bus_resources() call from pci_host_probe()
assign the bridge windows. Some host bridges, however, have to wait first
for the link up event before they can enumerate successfully (see e.g.
qcom_pcie_global_irq_thread()) and thus the bus has not been enumerated yet
while calling pci_host_probe().
Calling pci_assign_unassigned_root_bus_resources() without results from
enumeration can result in sizing bridge windows with too small sizes which
cannot be later corrected after the enumeration has completed because
bridge windows have become pinned in place by the other resources.
Interestingly, it seems pci_read_bridge_bases() is not called at all in the
problematic case and the bridge window resource type setup is done by
pci_bridge_check_ranges() and sizing by the usual resource fitting logic.
The root problem behind all this looks pretty generic. If resource fitting
is called too early, the hotplug reservation and old size lower bounding
cause the bridge windows to be assigned without children but with non-zero
size, which leads to these pinning problems. As such, this can likely be
solved on the general level but the solution does not look trivial.
As the commit a43ac325c7 ("PCI: Set up bridge resources earlier") was
prequisite for other change that did not end up into kernel yet, revert it
to resolve the resource assignment failures and give time to code and test
a generic solution.
Fixes: a43ac325c7 ("PCI: Set up bridge resources earlier")
Reported-by: Val Packett <val@packett.cool>
Link: https://lore.kernel.org/r/017ff8df-511c-4da8-b3cf-edf2cb7f1a67@packett.cool
Reported-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/df266709-a9b3-4fd8-af3a-c22eb3c9523a@roeck-us.net
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Link: https://patch.msgid.link/20251014163602.17138-1-ilpo.jarvinen@linux.intel.com
- Add rescan/remove locking when enabling/disabling SR-IOV, which solves
list corruption on s390, where disabling SR-IOV also generates hotplug
events (Niklas Schnelle)
- Add lockdep assertion in pci_stop_and_remove_bus_device() to catch
device removal without appropriate locking (Niklas Schnelle)
* pci/virtualization:
PCI: Add lockdep assertion in pci_stop_and_remove_bus_device()
PCI/IOV: Add PCI rescan-remove locking when enabling/disabling SR-IOV
- Ensure relaxed tail alignment does not increase min_align when computing
bridge window size, to fix a regression (Ilpo Järvinen)
- Fix bridge window size computation to fix a regression for devices with
undefined PCI class, e.g., Samsung [144d:a5a5] (Ilpo Järvinen)
- Fix error handling during resource resize to fix a regression in amdgpu
(Ilpo Järvinen)
- Align m68k pcibios_enable_device() with other arches (Ilpo Järvinen)
- Remove several sparc pcibios_enable_device() implementations that don't
do anything beyond what pci_enable_resources() does (Ilpo Järvinen)
- Remove mips pcibios_enable_resources() and use pci_enable_resources()
instead (Ilpo Järvinen)
- Refactor and simplify find_bus_resource_of_type() (Ilpo Järvinen)
- Claim bridge windows before setting them up (Ilpo Järvinen)
- Disable non-claimed bridge windows so the kernel's view matches the
hardware configuration (Ilpo Järvinen)
- Use pci_release_resource() instead of release_resource() to reduce code
duplication and increase consistency (Ilpo Järvinen)
- Enable bridges even if bridge window assignment fails (Ilpo Järvinen)
- Preserve bridge window resource type flags when assignment fails because
we may need it later (Ilpo Järvinen)
- Add bridge window selection functions to make the selection consistent
across the several places that do this (Ilpo Järvinen)
- Warn if bridge window cannot be released when resizing BAR (Ilpo
Järvinen)
- Set up bridge resources before enumerating children so we can check
whether child resources are inside bridge windows (Ilpo Järvinen)
* pci/resource:
PCI: Set up bridge resources earlier
PCI: Don't print stale information about resource
PCI: Alter misleading recursion to pci_bus_release_bridge_resources()
PCI: Pass bridge window to pci_bus_release_bridge_resources()
PCI: Add pci_setup_one_bridge_window()
PCI: Refactor remove_dev_resources() to use pbus_select_window()
PCI: Refactor distributing available memory to use loops
PCI: Use pbus_select_window_for_type() during mem window sizing
PCI: Use pbus_select_window() in space available checker
PCI: Rename resource variable from r to res
PCI: Use pbus_select_window_for_type() during IO window sizing
PCI: Use pbus_select_window() during BAR resize
PCI: Warn if bridge window cannot be released when resizing BAR
PCI: Fix finding bridge window in pci_reassign_bridge_resources()
PCI: Add bridge window selection functions
PCI: Add defines for bridge window indexing
PCI: Preserve bridge window resource type flags
PCI: Enable bridge even if bridge window fails to assign
PCI: Use pci_release_resource() instead of release_resource()
PCI: Disable non-claimed bridge window
PCI: Always claim bridge window before its setup
PCI: Refactor find_bus_resource_of_type() logic checks
PCI: Move find_bus_resource_of_type() earlier
MIPS: PCI: Use pci_enable_resources()
sparc/PCI: Remove pcibios_enable_device() as they do nothing extra
m68k/PCI: Use pci_enable_resources() in pcibios_enable_device()
PCI: Fix failure detection during resource resize
PCI: Fix pdev_resources_assignable() disparity
PCI: Ensure relaxed tail alignment does not increase min_align
- Fix a double cleanup of regulators if devm_add_action_or_reset() fails
(Geert Uytterhoeven)
* pci/pwrctrl:
PCI/pwrctrl: Fix device leak at device stop
PCI/pwrctrl: Fix device and OF node leak at bus scan
PCI/pwrctrl: Fix device leak at registration
PCI/pwrctrl: Fix double cleanup on devm_add_action_or_reset() failure
Bridge windows are read twice from PCI Config Space, the first time from
pci_read_bridge_windows(), which does not set up the device's resources.
This causes problems down the road as child resources of the bridge cannot
check whether they reside within the bridge window or not.
Set up the bridge windows already in pci_read_bridge_windows().
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Link: https://patch.msgid.link/20250924134228.1663-2-ilpo.jarvinen@linux.intel.com
include/linux/pci.h provides PCI_BRIDGE_{IO,MEM,PREF_MEM}_WINDOW defines,
however, they're based on the resource array indexing in the pci_dev
struct. The struct pci_bus also has pointers to those same resources but
they start from zeroth index.
Add PCI_BUS_BRIDGE_{IO,MEM,PREF_MEM}_WINDOW defines to get rid of literal
indexing.
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Link: https://patch.msgid.link/20250829131113.36754-12-ilpo.jarvinen@linux.intel.com
When a bridge window is found unused or fails to assign, the flags of the
associated resource are cleared. Clearing flags is problematic as it also
removes the type information of the resource which is needed later.
Thus, always preserve the bridge window type flags and use IORESOURCE_UNSET
and IORESOURCE_DISABLED to indicate the status of the bridge window. Also,
when initializing resources, make sure all valid bridge windows do get
their type flags set.
Change various places that relied on resource flags being cleared to check
for IORESOURCE_UNSET and IORESOURCE_DISABLED to allow bridge window
resource to retain their type flags. Add pdev_resource_assignable() and
pdev_resource_should_fit() helpers to filter out disabled bridge windows
during resource fitting; the latter combines more common checks into the
helper.
When reading the bridge windows from the registers, instead of leaving the
resource flags cleared for bridge windows that are not enabled, always
set up the flags and set IORESOURCE_UNSET | IORESOURCE_DISABLED as needed.
When resource fitting or assignment fails for a bridge window resource, or
the bridge window is not needed, mark the resource with IORESOURCE_UNSET or
IORESOURCE_DISABLED, respectively.
Use dummy zero resource in resource_show() for backwards compatibility as
lspci will otherwise misrepresent disabled bridge windows.
This change fixes an issue which highlights the importance of keeping the
resource type flags intact:
At the end of __assign_resources_sorted(), reset_resource() is called,
previously clearing the flags. Later, pci_prepare_next_assign_round()
attempted to release bridge resources using
pci_bus_release_bridge_resources() that calls into
pci_bridge_release_resources() that assumes type flags are still present.
As type flags were cleared, IORESOURCE_MEM_64 was not set leading to
resources under an incorrect bridge window to be released (idx = 1
instead of idx = 2). While the assignments performed later covered this
problem so that the wrongly released resources got assigned in the end,
it was still causing extra release+assign pairs.
There are other reasons why the resource flags should be retained in
upcoming changes too.
Removing the flag reset for non-bridge window resource is left as future
work, in part because it has a much higher regression potential due to
pci_enable_resources() that will start to work also for those resources
then and due to what endpoint drivers might assume about resources.
Despite the Fixes tag, backporting this (at least any time soon) is highly
discouraged. The issue fixed is borderline cosmetic as the later
assignments normally cover the problem entirely. Also there might be
non-obvious dependencies.
Fixes: 5b28541552 ("PCI: Restrict 64-bit prefetchable bridge windows to 64-bit resources")
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Link: https://patch.msgid.link/20250829131113.36754-11-ilpo.jarvinen@linux.intel.com
Pull PCI updates from Bjorn Helgaas:
"Enumeration:
- Allow built-in drivers, not just modular drivers, to use async
initial probing (Lukas Wunner)
- Support Immediate Readiness even on devices with no PM Capability
(Sean Christopherson)
- Consolidate definition of PCIE_RESET_CONFIG_WAIT_MS (100ms), the
required delay between a reset and sending config requests to a
device (Niklas Cassel)
- Add pci_is_display() to check for "Display" base class and use it
in ALSA hda, vfio, vga_switcheroo, vt-d (Mario Limonciello)
- Allow 'isolated PCI functions' (multi-function devices without a
function 0) for LoongArch, similar to s390 and jailhouse (Huacai
Chen)
Power control:
- Add ability to enable optional slot clock for cases where the PCIe
host controller and the slot are supplied by different clocks
(Marek Vasut)
PCIe native device hotplug:
- Fix runtime PM ref imbalance on Hot-Plug Capable ports caused by
misinterpreting a config read failure after a device has been
removed (Lukas Wunner)
- Avoid creating a useless PCIe port service device for pciehp if the
slot is handled by the ACPI hotplug driver (Lukas Wunner)
- Ignore ACPI hotplug slots when calculating depth of pciehp hotplug
ports (Lukas Wunner)
Virtualization:
- Save VF resizable BAR state and restore it after reset (Michał
Winiarski)
- Allow IOV resources (VF BARs) to be resized (Michał Winiarski)
- Add pci_iov_vf_bar_set_size() so drivers can control VF BAR size
(Michał Winiarski)
Endpoint framework:
- Add RC-to-EP doorbell support using platform MSI controller,
including a test case (Frank Li)
- Allow BAR assignment via configfs so platforms have flexibility in
determining BAR usage (Jerome Brunet)
Native PCIe controller drivers:
- Convert amazon,al-alpine-v[23]-pcie, apm,xgene-pcie,
axis,artpec6-pcie, marvell,armada-3700-pcie, st,spear1340-pcie to
DT schema format (Rob Herring)
- Use dev_fwnode() instead of of_fwnode_handle() to remove OF
dependency in altera (fixes an unused variable), designware-host,
mediatek, mediatek-gen3, mobiveil, plda, xilinx, xilinx-dma,
xilinx-nwl (Jiri Slaby, Arnd Bergmann)
- Convert aardvark, altera, brcmstb, designware-host, iproc,
mediatek, mediatek-gen3, mobiveil, plda, rcar-host, vmd, xilinx,
xilinx-dma, xilinx-nwl from using pci_msi_create_irq_domain() to
using msi_create_parent_irq_domain() instead; this makes the
interrupt controller per-PCI device, allows dynamic allocation of
vectors after initialization, and allows support of IMS (Nam Cao)
APM X-Gene PCIe controller driver:
- Rewrite MSI handling to MSI CPU affinity, drop useless CPU hotplug
bits, use device-managed memory allocations, and clean things up
(Marc Zyngier)
- Probe xgene-msi as a standard platform driver rather than a
subsys_initcall (Marc Zyngier)
Broadcom STB PCIe controller driver:
- Add optional DT 'num-lanes' property and if present, use it to
override the Maximum Link Width advertised in Link Capabilities
(Jim Quinlan)
Cadence PCIe controller driver:
- Use PCIe Message routing types from the PCI core rather than
defining private ones (Hans Zhang)
Freescale i.MX6 PCIe controller driver:
- Add IMX8MQ_EP third 64-bit BAR in epc_features (Richard Zhu)
- Add IMX8MM_EP and IMX8MP_EP fixed 256-byte BAR 4 in epc_features
(Richard Zhu)
- Configure LUT for MSI/IOMMU in Endpoint mode so Root Complex can
trigger doorbel on Endpoint (Frank Li)
- Remove apps_reset (LTSSM_EN) from
imx_pcie_{assert,deassert}_core_reset(), which fixes a hotplug
regression on i.MX8MM (Richard Zhu)
- Delay Endpoint link start until configfs 'start' written (Richard
Zhu)
Intel VMD host bridge driver:
- Add Intel Panther Lake (PTL)-H/P/U Vendor ID (George D Sworo)
Qualcomm PCIe controller driver:
- Add DT binding and driver support for SA8255p, which supports ECAM
for Configuration Space access (Mayank Rana)
- Update DT binding and driver to describe PHYs and per-Root Port
resets in a Root Port stanza and deprecate describing them in the
host bridge; this makes it possible to support multiple Root Ports
in the future (Krishna Chaitanya Chundru)
- Add Qualcomm QCS615 to SM8150 DT binding (Ziyue Zhang)
- Add Qualcomm QCS8300 to SA8775p DT binding (Ziyue Zhang)
- Drop TBU and ref clocks from Qualcomm SM8150 and SC8180x DT
bindings (Konrad Dybcio)
- Document 'link_down' reset in Qualcomm SA8775P DT binding (Ziyue
Zhang)
- Add required PCIE_RESET_CONFIG_WAIT_MS delay after Link up IRQ
(Niklas Cassel)
Rockchip PCIe controller driver:
- Drop unused PCIe Message routing and code definitions (Hans Zhang)
- Remove several unused header includes (Hans Zhang)
- Use standard PCIe config register definitions instead of
rockchip-specific redefinitions (Geraldo Nascimento)
- Set Target Link Speed to 5.0 GT/s before retraining so we have a
chance to train at a higher speed (Geraldo Nascimento)
Rockchip DesignWare PCIe controller driver:
- Prevent race between link training and register update via DBI by
inhibiting link training after hot reset and link down (Wilfred
Mallawa)
- Add required PCIE_RESET_CONFIG_WAIT_MS delay after Link up IRQ
(Niklas Cassel)
Sophgo PCIe controller driver:
- Add DT binding and driver for Sophgo SG2044 PCIe controller driver
in Root Complex mode (Inochi Amaoto)
Synopsys DesignWare PCIe controller driver:
- Add required PCIE_RESET_CONFIG_WAIT_MS after waiting for Link up on
Ports that support > 5.0 GT/s. Slower Ports still rely on the
not-quite-correct PCIE_LINK_WAIT_SLEEP_MS 90ms default delay while
waiting for the Link (Niklas Cassel)"
* tag 'pci-v6.17-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci: (116 commits)
dt-bindings: PCI: qcom,pcie-sa8775p: Document 'link_down' reset
dt-bindings: PCI: Remove 83xx-512x-pci.txt
dt-bindings: PCI: Convert amazon,al-alpine-v[23]-pcie to DT schema
dt-bindings: PCI: Convert marvell,armada-3700-pcie to DT schema
dt-bindings: PCI: Convert apm,xgene-pcie to DT schema
dt-bindings: PCI: Convert axis,artpec6-pcie to DT schema
dt-bindings: PCI: Convert st,spear1340-pcie to DT schema
PCI: Move is_pciehp check out of pciehp_is_native()
PCI: pciehp: Use is_pciehp instead of is_hotplug_bridge
PCI/portdrv: Use is_pciehp instead of is_hotplug_bridge
PCI/ACPI: Fix runtime PM ref imbalance on Hot-Plug Capable ports
selftests: pci_endpoint: Add doorbell test case
misc: pci_endpoint_test: Add doorbell test case
PCI: endpoint: pci-epf-test: Add doorbell test support
PCI: endpoint: Add pci_epf_align_inbound_addr() helper for inbound address alignment
PCI: endpoint: pci-ep-msi: Add checks for MSI parent and mutability
PCI: endpoint: Add RC-to-EP doorbell support using platform MSI controller
PCI: dwc: Add Sophgo SG2044 PCIe controller driver in Root Complex mode
PCI: vmd: Switch to msi_create_parent_irq_domain()
PCI: vmd: Convert to lock guards
...
- Fix runtime PM ref imbalance on Hot-Plug Capable ports caused by
misinterpreting a config read failure after a device has been removed
(Lukas Wunner)
- Avoid creating a useless PCIe port service device for pciehp if the slot
is handled by the ACPI hotplug driver (Lukas Wunner)
- Ignore ACPI hotplug slots when calculating depth of pciehp hotplug ports
(Lukas Wunner)
- Simplify pci_bridge_d3_possible() and clarify comments (Lukas Wunner)
* pci/hotplug:
PCI: Move is_pciehp check out of pciehp_is_native()
PCI: pciehp: Use is_pciehp instead of is_hotplug_bridge
PCI/portdrv: Use is_pciehp instead of is_hotplug_bridge
PCI/ACPI: Fix runtime PM ref imbalance on Hot-Plug Capable ports
pci_bridge_d3_possible() is called from both pcie_portdrv_probe() and
pcie_portdrv_remove() to determine whether runtime power management shall
be enabled (on probe) or disabled (on remove) on a PCIe port.
The underlying assumption is that pci_bridge_d3_possible() always returns
the same value, else a runtime PM reference imbalance would occur. That
assumption is not given if the PCIe port is inaccessible on remove due to
hot-unplug: pci_bridge_d3_possible() calls pciehp_is_native(), which
accesses Config Space to determine whether the port is Hot-Plug Capable.
An inaccessible port returns "all ones", which is converted to "all
zeroes" by pcie_capability_read_dword(). Hence the port no longer seems
Hot-Plug Capable on remove even though it was on probe.
The resulting runtime PM ref imbalance causes warning messages such as:
pcieport 0000:02:04.0: Runtime PM usage count underflow!
Avoid the Config Space access (and thus the runtime PM ref imbalance) by
caching the Hot-Plug Capable bit in struct pci_dev.
The struct already contains an "is_hotplug_bridge" flag, which however is
not only set on Hot-Plug Capable PCIe ports, but also Conventional PCI
Hot-Plug bridges and ACPI slots. The flag identifies bridges which are
allocated additional MMIO and bus number resources to allow for hierarchy
expansion.
The kernel is somewhat sloppily using "is_hotplug_bridge" in a number of
places to identify Hot-Plug Capable PCIe ports, even though the flag
encompasses other devices. Subsequent commits replace these occurrences
with the new flag to clearly delineate Hot-Plug Capable PCIe ports from
other kinds of hotplug bridges.
Document the existing "is_hotplug_bridge" and the new "is_pciehp" flag
and document the (non-obvious) requirement that pci_bridge_d3_possible()
always returns the same value across the entire lifetime of a bridge,
including its hot-removal.
Fixes: 5352a44a56 ("PCI: pciehp: Make pciehp_is_native() stricter")
Reported-by: Laurent Bigonville <bigon@bigon.be>
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=220216
Reported-by: Mario Limonciello <mario.limonciello@amd.com>
Closes: https://lore.kernel.org/r/20250609020223.269407-3-superm1@kernel.org/
Link: https://lore.kernel.org/all/20250620025535.3425049-3-superm1@kernel.org/T/#u
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Rafael J. Wysocki <rafael@kernel.org>
Cc: stable@vger.kernel.org # v4.18+
Link: https://patch.msgid.link/fe5dcc3b2e62ee1df7905d746bde161eb1b3291c.1752390101.git.lukas@wunner.de
If devicetree describes power supplies related to a PCI device, we
unnecessarily created a pwrctrl device even if CONFIG_PCI_PWRCTL was not
enabled.
We only need pci_pwrctrl_create_device() when CONFIG_PCI_PWRCTRL is
enabled. Compile it out when CONFIG_PCI_PWRCTRL is not enabled.
When pci_pwrctrl_create_device() creates and returns a pwrctrl device,
pci_scan_device() doesn't enumerate the PCI device. It assumes the pwrctrl
core will rescan the bus after turning on the power. However, if
CONFIG_PCI_PWRCTRL is not enabled, the rescan never happens, which breaks
PCI enumeration on any system that describes power supplies in devicetree
but does not use pwrctrl.
Jim reported that some brcmstb platforms break this way. The brcmstb
driver is still broken if CONFIG_PCI_PWRCTRL is enabled, but this commit at
least allows brcmstb to work when it's NOT enabled.
Fixes: 957f40d039 ("PCI/pwrctrl: Move creation of pwrctrl devices to pci_scan_device()")
Reported-by: Jim Quinlan <james.quinlan@broadcom.com>
Link: https://lore.kernel.org/r/CA+-6iNwgaByXEYD3j=-+H_PKAxXRU78svPMRHDKKci8AGXAUPg@mail.gmail.com
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
[bhelgaas: commit log]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Lukas Wunner <lukas@wunner.de>
Cc: stable@vger.kernel.org # v6.15
Link: https://patch.msgid.link/20250701064731.52901-1-manivannan.sadhasivam@linaro.org
Since commit 58d9a38f6f ("PCI: Skip attaching driver in device_add()"),
PCI enumeration is split into two steps: In the first step, all devices
are published in sysfs with device_add(). In the second step, drivers are
bound to the devices with device_attach(). To delay driver binding until
the second step, a "bool match_driver" in struct pci_dev is used.
Instead of a bool, use a bit in the "unsigned long priv_flags" to shrink
struct pci_dev a little and prevent use of the bool outside the PCI core
(as has happened with commit cbbc00be2c ("iommu/amd: Prevent binding
other PCI drivers to IOMMU PCI devices")).
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
Link: https://patch.msgid.link/d22a9e5b81d6bd8dd1837607d6156679b3b1199c.1745572340.git.lukas@wunner.de
Pull pci updates from Bjorn Helgaas:
"Enumeration:
- Enable Configuration RRS SV, which makes device readiness visible,
early instead of during child bus scanning (Bjorn Helgaas)
- Log debug messages about reset methods being used (Bjorn Helgaas)
- Avoid reset when it has been disabled via sysfs (Nishanth
Aravamudan)
- Add common pci-ep-bus.yaml schema for exporting several peripherals
of a single PCI function via devicetree (Andrea della Porta)
- 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)
Resource management:
- Enlarge devres table[] to accommodate bridge windows, ROM, IOV
BARs, etc., and validate BAR index in devres interfaces (Philipp
Stanner)
- 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)
- Allow drivers to enable devices even if we haven't assigned
optional IOV resources to them (Ilpo Järvinen)
- Rework handling of optional resources (IOV BARs, ROMs) to reduce
failures if we can't allocate them (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)
ASPM:
- Delay pcie_link_state deallocation to avoid dangling pointers that
cause invalid references during hot-unplug (Daniel Stodden)
Power management:
- Allow PCI bridges to go to D3Hot when suspending on all non-x86
systems (Manivannan Sadhasivam)
Power control:
- Create pwrctrl devices in pci_scan_device() to make it more
symmetric with pci_pwrctrl_unregister() and make pwrctrl devices
for PCI bridges possible (Manivannan Sadhasivam)
- Unregister pwrctrl devices in pci_destroy_dev() so DOE, ASPM, etc.
can still access devices after pci_stop_dev() (Manivannan
Sadhasivam)
- If there's a pwrctrl device for a PCI device, skip scanning it
because the pwrctrl core will rescan the bus after the device is
powered on (Manivannan Sadhasivam)
- Add a pwrctrl driver for PCI slots based on voltage regulators
described via devicetree (Manivannan Sadhasivam)
Bandwidth control:
- Add set_pcie_speed.sh to TEST_PROGS to fix issue when executing the
set_pcie_cooling_state.sh test case (Yi Lai)
- Avoid a NULL pointer dereference when we run out of bus numbers to
assign for a bridge secondary bus (Lukas Wunner)
Hotplug:
- Drop superfluous pci_hotplug_slot_list, try_module_get() calls, and
NULL pointer checks (Lukas Wunner)
- Drop shpchp module init/exit logging, replace shpchp dbg() with
ctrl_dbg(), and remove unused dbg(), err(), info(), warn() wrappers
(Ilpo Järvinen)
- Drop 'shpchp_debug' module parameter in favor of standard dynamic
debugging (Ilpo Järvinen)
- Drop unused cpcihp .get_power(), .set_power() function pointers
(Guilherme Giacomo Simoes)
- Disable hotplug interrupts in portdrv only when pciehp is not
enabled to avoid issuing two hotplug commands too close together
(Feng Tang)
- Skip pciehp 'device replaced' check if the device has been removed
to address a deadlock when resuming after a device was removed
during system sleep (Lukas Wunner)
- Don't enable pciehp hotplug interupt when resuming in poll mode
(Ilpo Järvinen)
Virtualization:
- Fix bugs in 'pci=config_acs=' kernel command line parameter (Tushar
Dave)
DOE:
- Expose supported DOE features via sysfs (Alistair Francis)
- Allow DOE support to be enabled even if CXL isn't enabled (Alistair
Francis)
Endpoint framework:
- Convert PCI device data so pci-epf-test works correctly on
big-endian endpoint systems (Niklas Cassel)
- Add BAR_RESIZABLE type to endpoint framework and add DWC core
support for EPF drivers to set BAR_RESIZABLE type and size (Niklas
Cassel)
- Fix pci-epf-test double free that causes an oops if the host
reboots and PERST# deassertion restarts endpoint BAR allocation
(Christian Bruel)
- Fix endpoint BAR testing so tests can skip disabled BARs instead of
reporting them as failures (Niklas Cassel)
- Widen endpoint test BAR size variable to accommodate BARs larger
than INT_MAX (Niklas Cassel)
- Remove unused tools 'pci' build target left over after moving tests
to tools/testing/selftests/pci_endpoint (Jianfeng Liu)
Altera PCIe controller driver:
- Add DT binding and driver support for Agilex family (P-Tile,
F-Tile, R-Tile) (Matthew Gerlach and D M, Sharath Kumar)
AMD MDB PCIe controller driver:
- Add DT binding and driver for AMD MDB (Multimedia DMA Bridge)
(Thippeswamy Havalige)
Broadcom STB PCIe controller driver:
- Add BCM2712 MSI-X DT binding and interrupt controller drivers and
add softdep on irq_bcm2712_mip driver to ensure that it is loaded
first (Stanimir Varbanov)
- Expand inbound window map to 64GB so it can accommodate BCM2712
(Stanimir Varbanov)
- Add BCM2712 support and DT updates (Stanimir Varbanov)
- Apply link speed restriction before bringing link up, not after
(Jim Quinlan)
- Update Max Link Speed in Link Capabilities via the internal
writable register, not the read-only config register (Jim Quinlan)
- Handle regulator_bulk_get() error to avoid panic when we call
regulator_bulk_free() later (Jim Quinlan)
- Disable regulators only when removing the bus immediately below a
Root Port because we don't support regulators deeper in the
hierarchy (Jim Quinlan)
- Make const read-only arrays static (Colin Ian King)
Cadence PCIe endpoint driver:
- Correct MSG TLP generation so endpoints can generate INTx messages
(Hans Zhang)
Freescale i.MX6 PCIe controller driver:
- Identify the second controller on i.MX8MQ based on devicetree
'linux,pci-domain' instead of DBI 'reg' address (Richard Zhu)
- Remove imx_pcie_cpu_addr_fixup() since dwc core can now derive the
ATU input address (using parent_bus_offset) from devicetree (Frank
Li)
Freescale Layerscape PCIe controller driver:
- Drop deprecated 'num-ib-windows' and 'num-ob-windows' and
unnecessary 'status' from example (Krzysztof Kozlowski)
- Correct the syscon_regmap_lookup_by_phandle_args("fsl,pcie-scfg")
arg_count to fix probe failure on LS1043A (Ioana Ciornei)
HiSilicon STB PCIe controller driver:
- Call phy_exit() to clean up if histb_pcie_probe() fails (Christophe
JAILLET)
Intel Gateway PCIe controller driver:
- Remove intel_pcie_cpu_addr() since dwc core can now derive the ATU
input address (using parent_bus_offset) from devicetree (Frank Li)
Intel VMD host bridge driver:
- Convert vmd_dev.cfg_lock from spinlock_t to raw_spinlock_t so
pci_ops.read() will never sleep, even on PREEMPT_RT where
spinlock_t becomes a sleepable lock, to avoid calling a sleeping
function from invalid context (Ryo Takakura)
MediaTek PCIe Gen3 controller driver:
- Remove leftover mac_reset assert for Airoha EN7581 SoC (Lorenzo
Bianconi)
- Add EN7581 PBUS controller 'mediatek,pbus-csr' DT property and
program host bridge memory aperture to this syscon node (Lorenzo
Bianconi)
Qualcomm PCIe controller driver:
- Add qcom,pcie-ipq5332 binding (Varadarajan Narayanan)
- Add qcom i.MX8QM and i.MX8QXP/DXP optional DMA interrupt (Alexander
Stein)
- Add optional dma-coherent DT property for Qualcomm SA8775P (Dmitry
Baryshkov)
- Make DT iommu property required for SA8775P and prohibited for
SDX55 (Dmitry Baryshkov)
- Add DT IOMMU and DMA-related properties for Qualcomm SM8450 (Dmitry
Baryshkov)
- Add endpoint DT properties for SAR2130P and enable endpoint mode in
driver (Dmitry Baryshkov)
- Describe endpoint BAR0 and BAR2 as 64-bit only and BAR1 and BAR3 as
RESERVED (Manivannan Sadhasivam)
Rockchip DesignWare PCIe controller driver:
- Describe rk3568 and rk3588 BARs as Resizable, not Fixed (Niklas
Cassel)
Synopsys DesignWare PCIe controller driver:
- Add debugfs-based Silicon Debug, Error Injection, Statistical
Counter support for DWC (Shradha Todi)
- Add debugfs property to expose LTSSM status of DWC PCIe link (Hans
Zhang)
- Add Rockchip support for DWC debugfs features (Niklas Cassel)
- Add dw_pcie_parent_bus_offset() to look up the parent bus address
of a specified 'reg' property and return the offset from the CPU
physical address (Frank Li)
- Use dw_pcie_parent_bus_offset() to derive CPU -> ATU addr offset
via 'reg[config]' for host controllers and 'reg[addr_space]' for
endpoint controllers (Frank Li)
- Apply struct dw_pcie.parent_bus_offset in ATU users to remove use
of .cpu_addr_fixup() when programming ATU (Frank Li)
TI J721E PCIe driver:
- Correct the 'link down' interrupt bit for J784S4 (Siddharth
Vadapalli)
TI Keystone PCIe controller driver:
- Describe AM65x BARs 2 and 5 as Resizable (not Fixed) and reduce
alignment requirement from 1MB to 64KB (Niklas Cassel)
Xilinx Versal CPM PCIe controller driver:
- Free IRQ domain in probe error path to avoid leaking it
(Thippeswamy Havalige)
- Add DT .compatible "xlnx,versal-cpm5nc-host" and driver support for
Versal Net CPM5NC Root Port controller (Thippeswamy Havalige)
- Add driver support for CPM5_HOST1 (Thippeswamy Havalige)
Miscellaneous:
- Convert fsl,mpc83xx-pcie binding to YAML (J. Neuschäfer)
- Use for_each_available_child_of_node_scoped() to simplify apple,
kirin, mediatek, mt7621, tegra drivers (Zhang Zekun)"
* tag 'pci-v6.15-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci: (197 commits)
PCI: layerscape: Fix arg_count to syscon_regmap_lookup_by_phandle_args()
PCI: j721e: Fix the value of .linkdown_irq_regfield for J784S4
misc: pci_endpoint_test: Add support for PCITEST_IRQ_TYPE_AUTO
PCI: endpoint: pci-epf-test: Expose supported IRQ types in CAPS register
PCI: dw-rockchip: Endpoint mode cannot raise INTx interrupts
PCI: endpoint: Add intx_capable to epc_features struct
dt-bindings: PCI: Add common schema for devices accessible through PCI BARs
PCI: intel-gw: Remove intel_pcie_cpu_addr()
PCI: imx6: Remove imx_pcie_cpu_addr_fixup()
PCI: dwc: Use parent_bus_offset to remove need for .cpu_addr_fixup()
PCI: dwc: ep: Ensure proper iteration over outbound map windows
PCI: dwc: ep: Use devicetree 'reg[addr_space]' to derive CPU -> ATU addr offset
PCI: dwc: ep: Consolidate devicetree handling in dw_pcie_ep_get_resources()
PCI: dwc: ep: Call epc_create() early in dw_pcie_ep_init()
PCI: dwc: Use devicetree 'reg[config]' to derive CPU -> ATU addr offset
PCI: dwc: Add dw_pcie_parent_bus_offset() checking and debug
PCI: dwc: Add dw_pcie_parent_bus_offset()
PCI/bwctrl: Fix NULL pointer dereference on bus number exhaustion
PCI: xilinx-cpm: Add cpm_csr register mapping for CPM5_HOST1 variant
PCI: brcmstb: Make const read-only arrays static
...
- 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()
- Create pwrctrl devices in pci_scan_device() to make it more symmetric
with pci_pwrctrl_unregister() and make pwrctrl devices for PCI bridges
possible (Manivannan Sadhasivam)
- Unregister pwrctrl devices in pci_destroy_dev() so DOE, ASPM, etc. can
still access devices after pci_stop_dev() (Manivannan Sadhasivam)
- If there's a pwrctrl device for a PCI device, skip scanning it because
the pwrctrl core will rescan the bus after the device is powered on
(Manivannan Sadhasivam)
- Add a pwrctrl driver for PCI slots based on voltage regulators described
via devicetree (Manivannan Sadhasivam)
* pci/pwrctrl:
PCI/pwrctrl: Add pwrctrl driver for PCI slots
dt-bindings: vendor-prefixes: Document the 'pciclass' prefix
PCI/pwrctrl: Skip scanning for the device further if pwrctrl device is created
PCI/pwrctrl: Move pci_pwrctrl_unregister() to pci_destroy_dev()
PCI/pwrctrl: Move creation of pwrctrl devices to pci_scan_device()
- 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
- 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
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>
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>
Following a reset, a Function may respond to Config Requests with Request
Retry Status (RRS) Completion Status to indicate that it is temporarily
unable to process the Request, but will be able to process the Request in
the future (PCIe r6.0, sec 2.3.1).
If the Configuration RRS Software Visibility feature is enabled and a Root
Complex receives RRS for a config read of the Vendor ID, the Root Complex
completes the Request to the host by returning PCI_VENDOR_ID_PCI_SIG,
0x0001 (sec 2.3.2).
The Config RRS SV feature applies only to Root Ports and is not directly
related to pci_scan_bridge_extend(). Move the RRS SV enable to
set_pcie_port_type() where we handle other PCIe-specific configuration.
Link: https://lore.kernel.org/r/20250303210217.199504-1-helgaas@kernel.org
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
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>
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>
Current way of creating pwrctrl devices requires iterating through the
child devicetree nodes of the PCI bridge in pci_pwrctrl_create_devices().
Even though it works, it creates confusion as there is no symmetry between
this and pci_pwrctrl_unregister() function that removes the pwrctrl
devices.
So to make these two functions symmetric, move the creation of pwrctrl
devices to pci_scan_device(). During the scan of each device in a slot,
the devicetree node (if exists) for the PCI device will be checked. If it
has the supplies populated, then the pwrctrl device will be created.
Since the PCI device scan happens so early, there would be no "struct
pci_dev" available for the device. So the host bridge is used as the
parent of all pwrctrl devices.
One nice side effect of this move is that, it is now possible to have
pwrctrl devices for PCI bridges as well (to control the supplies of PCI
slots).
Suggested-by: Lukas Wunner <lukas@wunner.de>
Tested-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20250116-pci-pwrctrl-slot-v3-1-827473c8fbf4@linaro.org
[kwilczynski: commit log]
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
- 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
