Commit Graph

972 Commits

Author SHA1 Message Date
Lukas Wunner 2cc8973bdc PCI/DPC: Fix use-after-free on concurrent DPC and hot-removal
commit 11a1f4bc47362700fcbde717292158873fb847ed upstream.

Keith reports a use-after-free when a DPC event occurs concurrently to
hot-removal of the same portion of the hierarchy:

The dpc_handler() awaits readiness of the secondary bus below the
Downstream Port where the DPC event occurred.  To do so, it polls the
config space of the first child device on the secondary bus.  If that
child device is concurrently removed, accesses to its struct pci_dev
cause the kernel to oops.

That's because pci_bridge_wait_for_secondary_bus() neglects to hold a
reference on the child device.  Before v6.3, the function was only
called on resume from system sleep or on runtime resume.  Holding a
reference wasn't necessary back then because the pciehp IRQ thread
could never run concurrently.  (On resume from system sleep, IRQs are
not enabled until after the resume_noirq phase.  And runtime resume is
always awaited before a PCI device is removed.)

However starting with v6.3, pci_bridge_wait_for_secondary_bus() is also
called on a DPC event.  Commit 53b54ad074 ("PCI/DPC: Await readiness
of secondary bus after reset"), which introduced that, failed to
appreciate that pci_bridge_wait_for_secondary_bus() now needs to hold a
reference on the child device because dpc_handler() and pciehp may
indeed run concurrently.  The commit was backported to v5.10+ stable
kernels, so that's the oldest one affected.

Add the missing reference acquisition.

Abridged stack trace:

  BUG: unable to handle page fault for address: 00000000091400c0
  CPU: 15 PID: 2464 Comm: irq/53-pcie-dpc 6.9.0
  RIP: pci_bus_read_config_dword+0x17/0x50
  pci_dev_wait()
  pci_bridge_wait_for_secondary_bus()
  dpc_reset_link()
  pcie_do_recovery()
  dpc_handler()

Fixes: 53b54ad074 ("PCI/DPC: Await readiness of secondary bus after reset")
Closes: https://lore.kernel.org/r/20240612181625.3604512-3-kbusch@meta.com/
Link: https://lore.kernel.org/linux-pci/8e4bcd4116fd94f592f2bf2749f168099c480ddf.1718707743.git.lukas@wunner.de
Reported-by: Keith Busch <kbusch@kernel.org>
Tested-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Cc: stable@vger.kernel.org # v5.10+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-08-03 08:54:34 +02:00
Ilpo Järvinen fae0e055d0 PCI: Do not wait for disconnected devices when resuming
[ Upstream commit 6613443ffc49d03e27f0404978f685c4eac43fba ]

On runtime resume, pci_dev_wait() is called:

  pci_pm_runtime_resume()
    pci_pm_bridge_power_up_actions()
      pci_bridge_wait_for_secondary_bus()
        pci_dev_wait()

While a device is runtime suspended along with its PCI hierarchy, the
device could get disconnected. In such case, the link will not come up no
matter how long pci_dev_wait() waits for it.

Besides the above mentioned case, there could be other ways to get the
device disconnected while pci_dev_wait() is waiting for the link to come
up.

Make pci_dev_wait() exit if the device is already disconnected to avoid
unnecessary delay.

The use cases of pci_dev_wait() boil down to two:

  1. Waiting for the device after reset
  2. pci_bridge_wait_for_secondary_bus()

The callers in both cases seem to benefit from propagating the
disconnection as error even if device disconnection would be more
analoguous to the case where there is no device in the first place which
return 0 from pci_dev_wait(). In the case 2, it results in unnecessary
marking of the devices disconnected again but that is just harmless extra
work.

Also make sure compiler does not become too clever with dev->error_state
and use READ_ONCE() to force a fetch for the up-to-date value.

Link: https://lore.kernel.org/r/20240208132322.4811-1-ilpo.jarvinen@linux.intel.com
Reported-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-27 13:49:05 +02:00
Mario Limonciello 7196289190 PCI/PM: Avoid D3cold for HP Pavilion 17 PC/1972 PCIe Ports
[ Upstream commit 256df20c590bf0e4d63ac69330cf23faddac3e08 ]

Hewlett-Packard HP Pavilion 17 Notebook PC/1972 is an Intel Ivy Bridge
system with a muxless AMD Radeon dGPU.  Attempting to use the dGPU fails
with the following sequence:

  ACPI Error: Aborting method \AMD3._ON due to previous error (AE_AML_LOOP_TIMEOUT) (20230628/psparse-529)
  radeon 0000:01:00.0: not ready 1023ms after resume; waiting
  radeon 0000:01:00.0: not ready 2047ms after resume; waiting
  radeon 0000:01:00.0: not ready 4095ms after resume; waiting
  radeon 0000:01:00.0: not ready 8191ms after resume; waiting
  radeon 0000:01:00.0: not ready 16383ms after resume; waiting
  radeon 0000:01:00.0: not ready 32767ms after resume; waiting
  radeon 0000:01:00.0: not ready 65535ms after resume; giving up
  radeon 0000:01:00.0: Unable to change power state from D3cold to D0, device inaccessible

The issue is that the Root Port the dGPU is connected to can't handle the
transition from D3cold to D0 so the dGPU can't properly exit runtime PM.

The existing logic in pci_bridge_d3_possible() checks for systems that are
newer than 2015 to decide that D3 is safe.  This would nominally work for
an Ivy Bridge system (which was discontinued in 2015), but this system
appears to have continued to receive BIOS updates until 2017 and so this
existing logic doesn't appropriately capture it.

Add the system to bridge_d3_blacklist to prevent D3cold from being used.

Link: https://lore.kernel.org/r/20240307163709.323-1-mario.limonciello@amd.com
Reported-by: Eric Heintzmann <heintzmann.eric@free.fr>
Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/3229
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Tested-by: Eric Heintzmann <heintzmann.eric@free.fr>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-27 13:49:04 +02:00
Ilpo Järvinen 0053891e2f PCI: Wait for Link Training==0 before starting Link retrain
[ Upstream commit 73cb3a35f94db723c0211ad099bce55b2155e3f0 ]

Two changes were made in link retraining logic independent of each other.

The commit e7e3975636 ("PCI/ASPM: Avoid link retraining race") added a
check to pcie_retrain_link() to ensure no Link Training is currently active
to address the Implementation Note in PCIe r6.1 sec 7.5.3.7. At that time
pcie_wait_for_retrain() only checked for the Link Training (LT) bit being
cleared.

The commit 680e9c47a2 ("PCI: Add support for polling DLLLA to
pcie_retrain_link()") generalized pcie_wait_for_retrain() into
pcie_wait_for_link_status() which can wait either for LT or the Data Link
Layer Link Active (DLLLA) bit with 'use_lt' argument and supporting waiting
for either cleared or set using 'active' argument.

In the merge commit 1abb473903 ("Merge branch 'pci/enumeration'"), those
two divergent branches converged. The merge changed LT bit checking added
in the commit e7e3975636 ("PCI/ASPM: Avoid link retraining race") to now
wait for completion of any ongoing Link Training using DLLLA bit being set
if 'use_lt' is false.

When 'use_lt' is false, the pseudo-code steps of what occurs in
pcie_retrain_link():

	1. Wait for DLLLA==1
	2. Trigger link to retrain
	3. Wait for DLLLA==1

Step 3 waits for the link to come up from the retraining triggered by Step
2. As Step 1 is supposed to wait for any ongoing retraining to end, using
DLLLA also for it does not make sense because link training being active is
still indicated using LT bit, not with DLLLA.

Correct the pcie_wait_for_link_status() parameters in Step 1 to only wait
for LT==0 to ensure there is no ongoing Link Training.

This only impacts the Target Speed quirk, which is the only case where
waiting for DLLLA bit is used. It currently works in the problematic case
by means of link training getting initiated by hardware repeatedly and
respecting the new link parameters set by the caller, which then make
training succeed and bring the link up, setting DLLLA and causing
pcie_wait_for_link_status() to return success. We are not supposed to rely
on luck and need to make sure that LT transitioned through the inactive
state though before we initiate link training by hand via RL (Retrain Link)
bit.

Fixes: 1abb473903 ("Merge branch 'pci/enumeration'")
Link: https://lore.kernel.org/r/20240423130820.43824-1-ilpo.jarvinen@linux.intel.com
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-12 11:12:23 +02:00
Johan Hovold b0f4478838 PCI/ASPM: Fix deadlock when enabling ASPM
commit 1e560864159d002b453da42bd2c13a1805515a20 upstream.

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: f93e71aea6c6 ("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
[bhelgaas: backported to v6.6.y, which contains 8cc22ba3f7 ("Revert
 "PCI/ASPM: Remove pcie_aspm_pm_state_change()""), a backport of
 f93e71aea6c6.  This omits the drivers/pci/controller/dwc/pcie-qcom.c hunk
 that updates qcom_pcie_enable_aspm(), which was added by 9f4f3dfad8cf
 ("PCI: qcom: Enable ASPM for platforms supporting 1.9.0 ops"), which is not
 present in v6.6.28.]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-04-27 17:11:44 +02:00
Alex Williamson 63b1a3d9dd PCI: Fix active state requirement in PME polling
[ Upstream commit 41044d5360685e78a869d40a168491a70cdb7e73 ]

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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-02-23 09:24:58 +01:00
Bjorn Helgaas 8cc22ba3f7 Revert "PCI/ASPM: Remove pcie_aspm_pm_state_change()"
commit f93e71aea6c60ebff8adbd8941e678302d377869 upstream.

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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-01-10 17:16:46 +01:00
Bjorn Helgaas 58c91b699c PCI: Use FIELD_GET() in Sapphire RX 5600 XT Pulse quirk
[ Upstream commit 04e82fa5951ca66495d7b05665eff673aa3852b4 ]

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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-11-28 17:19:44 +00:00
Ilpo Järvinen d4c5d6fc2b PCI: Use FIELD_GET() to extract Link Width
[ Upstream commit d1f9b39da4a5347150246871325190018cda8cb3 ]

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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-11-28 17:19:44 +00:00
Ilpo Järvinen eaea9f7b44 PCI: Do error check on own line to split long "if" conditions
[ Upstream commit d15f18053e5cc5576af9e7eef0b2a91169b6326d ]

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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-11-28 17:19:43 +00:00
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
Huacai Chen 8b3517f88f PCI: loongson: Prevent LS7A MRRS increases
Except for isochronous-configured devices, software may set
Max_Read_Request_Size (MRRS) to any value up to 4096.  If a device issues a
read request with size greater than the completer's Max_Payload_Size (MPS),
the completer is required to break the response into multiple completions.

Instead of correctly responding with multiple completions to a large read
request, some LS7A Root Ports respond with a Completer Abort.  To prevent
this, the MRRS must be limited to an implementation-specific value.

The OS cannot detect that value, so rely on BIOS to configure MRRS before
booting, and quirk the Root Ports so we never set an MRRS larger than that
BIOS value for any downstream device.

N.B. Hot-added devices are not configured by BIOS, and they power up with
MRRS = 512 bytes, so these devices will be limited to 512 bytes.  If the
LS7A limit is smaller, those hot-added devices may not work correctly, but
per [1], hotplug is not supported with this chipset revision.

[1] https://lore.kernel.org/r/073638a7-ae68-2847-ac3d-29e5e760d6af@loongson.cn

[bhelgaas: commit log]
Link: https://bugzilla.kernel.org/show_bug.cgi?id=216884
Link: https://lore.kernel.org/r/20230201043018.778499-3-chenhuacai@loongson.cn
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2023-02-01 12:49:29 -06:00
Michael S. Tsirkin 98b04dd0b4 PCI: Fix pci_device_is_present() for VFs by checking PF
pci_device_is_present() previously didn't work for VFs because it reads the
Vendor and Device ID, which are 0xffff for VFs, which looks like they
aren't present.  Check the PF instead.

Wei Gong reported that if virtio I/O is in progress when the driver is
unbound or "0" is written to /sys/.../sriov_numvfs, the virtio I/O
operation hangs, which may result in output like this:

  task:bash state:D stack:    0 pid: 1773 ppid:  1241 flags:0x00004002
  Call Trace:
   schedule+0x4f/0xc0
   blk_mq_freeze_queue_wait+0x69/0xa0
   blk_mq_freeze_queue+0x1b/0x20
   blk_cleanup_queue+0x3d/0xd0
   virtblk_remove+0x3c/0xb0 [virtio_blk]
   virtio_dev_remove+0x4b/0x80
   ...
   device_unregister+0x1b/0x60
   unregister_virtio_device+0x18/0x30
   virtio_pci_remove+0x41/0x80
   pci_device_remove+0x3e/0xb0

This happened because pci_device_is_present(VF) returned "false" in
virtio_pci_remove(), so it called virtio_break_device().  The broken vq
meant that vring_interrupt() skipped the vq.callback() that would have
completed the virtio I/O operation via virtblk_done().

[bhelgaas: commit log, simplify to always use pci_physfn(), add stable tag]
Link: https://lore.kernel.org/r/20221026060912.173250-1-mst@redhat.com
Reported-by: Wei Gong <gongwei833x@gmail.com>
Tested-by: Wei Gong <gongwei833x@gmail.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: stable@vger.kernel.org
2022-11-11 17:37:56 -06:00
Pali Rohár c14f7ccc9f PCI: Assign PCI domain IDs by ida_alloc()
Replace assignment of PCI domain IDs from atomic_inc_return() to
ida_alloc().

Use two IDAs, one for static domain allocations (those which are defined in
device tree) and second for dynamic allocations (all other).

During removal of root bus / host bridge, also release the domain ID.  The
released ID can be reused again, for example when dynamically loading and
unloading native PCI host bridge drivers.

This change also allows to mix static device tree assignment and dynamic by
kernel as all static allocations are reserved in dynamic pool.

[bhelgaas: set "err" if "bus->domain_nr < 0"]
Link: https://lore.kernel.org/r/20220714184130.5436-1-pali@kernel.org
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2022-11-08 11:14:18 -06:00
Bjorn Helgaas 034f93fcb1 Merge branch 'pci/pm'
- Cache the PTM capability offset instead of searching for it every time
  (Bjorn Helgaas)

- Separate PTM configuration from PTM enable (Bjorn Helgaas)

- Add pci_suspend_ptm() and pci_resume_ptm() to disable and re-enable PTM
  on suspend/resume so some Root Ports can safely enter a lower-power PM
  state (Bjorn Helgaas)

- Disable PTM for all devices during suspend; previously we only did this
  for Root Ports and even then only in certain cases (Bjorn Helgaas)

- Simplify pci_pm_suspend_noirq() (Rajvi Jingar)

- Reduce the delay after transitions to/from D3hot by using usleep_range()
  instead of msleep(), which reduces the typical delay from 19ms to 10ms
  (Sajid Dalvi, Will McVicker)

* pci/pm:
  PCI/PM: Reduce D3hot delay with usleep_range()
  PCI/PM: Simplify pci_pm_suspend_noirq()
  PCI/PM: Always disable PTM for all devices during suspend
  PCI/PTM: Consolidate PTM interface declarations
  PCI/PTM: Reorder functions in logical order
  PCI/PTM: Preserve RsvdP bits in PTM Control register
  PCI/PTM: Move pci_ptm_info() body into its only caller
  PCI/PTM: Add pci_suspend_ptm() and pci_resume_ptm()
  PCI/PTM: Separate configuration and enable
  PCI/PTM: Add pci_upstream_ptm() helper
  PCI/PTM: Cache PTM Capability offset
2022-10-05 17:32:53 -05:00
Vidya Sagar 4ff116d0d5 PCI/ASPM: Save L1 PM Substates Capability for suspend/resume
Previously the L1 PM Substates Control Registers (CTL1 and CTL2) weren't
saved and restored during suspend/resume leading to the L1 PM Substates
configuration being lost post-resume.

Save the L1 PM Substates Control Registers so that the configuration is
retained post-resume.

[bhelgaas: drop pci_is_pcie() testing; we can rely on pci_configure_ltr()
having already done that]
Link: https://lore.kernel.org/r/20220913131822.16557-3-vidyas@nvidia.com
Signed-off-by: Vidya Sagar <vidyas@nvidia.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2022-10-04 20:35:40 -05:00
Sajid Dalvi 3e347969a5 PCI/PM: Reduce D3hot delay with usleep_range()
PCIe r6.0, sec 5.9, requires a 10ms delay between programming a device to
change to or from D3hot and the time the device is next accessed (unless
Readiness Notifications are used).

The 10ms value (PCI_PM_D3HOT_WAIT) doesn't appear directly here because
some chipsets require 120ms for devices *below* them (pci_pm_d3hot_delay)
and some devices require more or less than 10ms (dev->d3hot_delay).

But msleep(10) typically waits about *20*ms, which is more than we need.
Switch to usleep_range() to improve the delay accuracy.

Based on a commit from Sajid in the Pixel 6 kernel tree [1].  On a Pixel 6,
the 10ms delay for the Exynos PCIe device delayed for an average of 19ms.
Switching to usleep_range() decreased the resume time by about 9ms.

[1] 18a8cad68d

[bhelgaas commit log, add timers-howto.rst link]
Link: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/timers/timers-howto.rst?id=v5.19#n73
Link: https://lore.kernel.org/r/20220921212735.2131588-1-willmcvicker@google.com
Signed-off-by: Sajid Dalvi <sdalvi@google.com>
Signed-off-by: Will McVicker <willmcvicker@google.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Matthias Kaehlcke <mka@chromium.org>
2022-09-29 14:31:40 -05:00
Bjorn Helgaas c01163dbd1 PCI/PM: Always disable PTM for all devices during suspend
We want to disable PTM on Root Ports because that allows some chips, e.g.,
Intel mobile chips since Coffee Lake, to enter a lower-power PM state.

That means we also have to disable PTM on downstream devices.  PCIe r6.0,
sec 2.2.8, recommends that functions support generation of messages in
non-D0 states, so we have to assume Switch Upstream Ports or Endpoints may
send PTM Requests while in D1, D2, and D3hot.  A PTM message received by a
Downstream Port (including a Root Port) with PTM disabled must be treated
as an Unsupported Request (sec 6.21.3).

PTM was previously disabled only for Root Ports, and it was disabled in
pci_prepare_to_sleep(), which is not called at all if a driver supports
legacy PM or does its own state saving.

Instead, disable PTM early in pci_pm_suspend() and pci_pm_runtime_suspend()
so we do it in all cases.

Previously PTM was disabled *after* saving device state, so the state
restore on resume automatically re-enabled it.  Since we now disable PTM
*before* saving state, we must explicitly re-enable it in pci_pm_resume()
and pci_pm_runtime_resume().

Here's a sample of errors that occur when PTM is disabled only on the Root
Port.  With this topology:

  0000:00:1d.0 Root Port            to [bus 08-71]
  0000:08:00.0 Switch Upstream Port to [bus 09-71]

Kai-Heng reported errors like this:

  pcieport 0000:00:1d.0:    [20] UnsupReq               (First)
  pcieport 0000:00:1d.0: AER:   TLP Header: 34000000 08000052 00000000 00000000

Decoding TLP header 0x34...... (0011 0100b) and 0x08000052:

  Fmt                         001b  4 DW header, no data
  Type                     1 0100b  Msg (Local - Terminate at Receiver)
  Requester ID  0x0800              Bus 08 Devfn 00.0
  Message Code    0x52  0101 0010b  PTM Request

The 00:1d.0 Root Port logged an Unsupported Request error when it received
a PTM Request with Requester ID 08:00.0.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=215453
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=216210
Fixes: a697f072f5 ("PCI: Disable PTM during suspend to save power")
Link: https://lore.kernel.org/r/20220909202505.314195-10-helgaas@kernel.org
Reported-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
Tested-by: Rajvi Jingar <rajvi.jingar@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2022-09-12 15:30:01 -05:00
Bjorn Helgaas e8bdc5ea48 PCI/PTM: Add pci_suspend_ptm() and pci_resume_ptm()
We disable PTM during suspend because that allows some Root Ports to enter
lower-power PM states, which means we also need to disable PTM for all
downstream devices.  Add pci_suspend_ptm() and pci_resume_ptm() for this
purpose.

pci_enable_ptm() and pci_disable_ptm() are for drivers to use to enable or
disable PTM.  They use dev->ptm_enabled to keep track of whether PTM should
be enabled.

pci_suspend_ptm() and pci_resume_ptm() are PCI core-internal functions to
temporarily disable PTM during suspend and (depending on dev->ptm_enabled)
re-enable PTM during resume.

Enable/disable/suspend/resume all use internal __pci_enable_ptm() and
__pci_disable_ptm() functions that only update the PTM Control register.
Outline:

  pci_enable_ptm(struct pci_dev *dev)
  {
     __pci_enable_ptm(dev);
     dev->ptm_enabled = 1;
     pci_ptm_info(dev);
  }

  pci_disable_ptm(struct pci_dev *dev)
  {
     if (dev->ptm_enabled) {
       __pci_disable_ptm(dev);
       dev->ptm_enabled = 0;
     }
  }

  pci_suspend_ptm(struct pci_dev *dev)
  {
     if (dev->ptm_enabled)
       __pci_disable_ptm(dev);
  }

  pci_resume_ptm(struct pci_dev *dev)
  {
     if (dev->ptm_enabled)
       __pci_enable_ptm(dev);
  }

Nothing currently calls pci_resume_ptm(); the suspend path saves the PTM
state before disabling PTM, so the PTM state restore in the resume path
implicitly re-enables it.  A future change will use pci_resume_ptm() to fix
some problems with this approach.

Link: https://lore.kernel.org/r/20220909202505.314195-5-helgaas@kernel.org
Tested-by: Rajvi Jingar <rajvi.jingar@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2022-09-12 15:29:37 -05:00
Bjorn Helgaas c4f36c3ab0 Merge branch 'pci/header-cleanup-immutable'
- Remove pci_get_legacy_ide_irq(); use ATA_PRIMARY_IRQ() and
  ATA_SECONDARY_IRQ() instead (Stafford Horne)

- Remove isa_dma_bridge_buggy, except for x86_32, the only place it's used
  (Stafford Horne)

- Define ARCH_GENERIC_PCI_MMAP_RESOURCE for csky (Stafford Horne)

- Move common PCI definitions that arches sometimes override to
  asm-generic/pci.h (Stafford Horne)

- Include <linux/isa-dma.h> for 'isa_dma_bridge_buggy' when needed
  (bisection hole here) (Randy Dunlap)

* pci/header-cleanup-immutable:
  PCI: Stub __pci_ioport_map() for arches that don't support it at all
  x86/cyrix: include header linux/isa-dma.h
  asm-generic: Add new pci.h and use it
  csky: PCI: Define ARCH_GENERIC_PCI_MMAP_RESOURCE
  PCI: Move isa_dma_bridge_buggy out of asm/dma.h
  PCI: Remove pci_get_legacy_ide_irq() and asm-generic/pci.h
2022-08-04 11:46:53 -05:00