Commit Graph

188 Commits

Author SHA1 Message Date
Manivannan Sadhasivam efdfa92a82 bus: mhi: ep: Rename read_from_host() and write_to_host() APIs
[ Upstream commit 927105244f8bc48e6841826a5644c6a961e03b5d ]

In the preparation for adding async API support, let's rename the existing
APIs to read_sync() and write_sync() to make it explicit that these APIs
are used for synchronous read/write.

Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Stable-dep-of: c7d0b2db5bc5 ("bus: mhi: ep: Do not allocate memory for MHI objects from DMA zone")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-10-17 15:24:09 +02:00
Dan Carpenter 3750e92ccc PCI: endpoint: Fix error handling in epf_ntb_epc_cleanup()
[ Upstream commit 6bba3c0ac5dc54737998a0982b2e272242c87e0f ]

There are two issues related to epf_ntb_epc_cleanup():

  1) It should call epf_ntb_config_sspad_bar_clear()
  2) The epf_ntb_bind() function should call epf_ntb_epc_cleanup()
     to cleanup.

I also changed the ordering a bit.  Unwinding should be done in the
mirror order from how they are allocated.

Fixes: e35f56bb03 ("PCI: endpoint: Support NTB transfer between RC and EP")
Link: https://lore.kernel.org/linux-pci/aaffbe8d-7094-4083-8146-185f4a84e8a1@moroto.mountain
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-08-03 08:54:01 +02:00
Dan Carpenter 0e27e2e869 PCI: endpoint: Clean up error handling in vpci_scan_bus()
[ Upstream commit 8e0f5a96c534f781e8c57ca30459448b3bfe5429 ]

Smatch complains about inconsistent NULL checking in vpci_scan_bus():

    drivers/pci/endpoint/functions/pci-epf-vntb.c:1024 vpci_scan_bus() error: we previously assumed 'vpci_bus' could be null (see line 1021)

Instead of printing an error message and then crashing we should return
an error code and clean up.

Also the NULL check is reversed so it prints an error for success
instead of failure.

Fixes: e35f56bb03 ("PCI: endpoint: Support NTB transfer between RC and EP")
Link: https://lore.kernel.org/linux-pci/68e0f6a4-fd57-45d0-945b-0876f2c8cb86@moroto.mountain
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-08-03 08:54:00 +02:00
Yang Yingliang a039690d32 NTB: fix possible name leak in ntb_register_device()
[ Upstream commit aebfdfe39b9327a3077d0df8db3beb3160c9bdd0 ]

If device_register() fails in ntb_register_device(), the device name
allocated by dev_set_name() should be freed. As per the comment in
device_register(), callers should use put_device() to give up the
reference in the error path. So fix this by calling put_device() in the
error path so that the name can be freed in kobject_cleanup().

As a result of this, put_device() in the error path of
ntb_register_device() is removed and the actual error is returned.

Fixes: a1bd3baeb2 ("NTB: Add NTB hardware abstraction layer")
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/20231201033057.1399131-1-yangyingliang@huaweicloud.com
[mani: reworded commit message]
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-03-26 18:19:48 -04:00
Manivannan Sadhasivam 96227df846 PCI: epf-mhi: Fix the DMA data direction of dma_unmap_single()
[ Upstream commit 327ec5f70609cf00c6f961073c01857555c6a8eb ]

In the error path of pci_epf_mhi_edma_write() function, the DMA data
direction passed (DMA_FROM_DEVICE) doesn't match the actual direction used
for the data transfer. Fix it by passing the correct one (DMA_TO_DEVICE).

Fixes: 7b99aaadda ("PCI: epf-mhi: Add eDMA support")
Reviewed-by: Krzysztof Wilczyński <kw@linux.com>
Link: https://lore.kernel.org/r/20231214063328.40657-1-manivannan.sadhasivam@linaro.org
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-25 15:35:53 -08:00
Manivannan Sadhasivam ad671dfce2 bus: mhi: ep: Pass mhi_ep_buf_info struct to read/write APIs
[ Upstream commit b08ded2ef2e98768d5ee5f71da8fe768b1f7774b ]

In the preparation of DMA async support, let's pass the parameters to
read_from_host() and write_to_host() APIs using mhi_ep_buf_info structure.

No functional change.

Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Stable-dep-of: 327ec5f70609 ("PCI: epf-mhi: Fix the DMA data direction of dma_unmap_single()")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-25 15:35:53 -08:00
Dan Carpenter 88aa0b599b PCI: endpoint: Fix double free in __pci_epc_create()
[ Upstream commit c9501d268944d6c0475ecb3e740a084a7da9cbfe ]

The pci_epc_release() function frees "epc" so the kfree() on the next line
is a double free.  Drop the redundant free.

Fixes: 7711cbb486 ("PCI: endpoint: Fix WARN() when an endpoint driver is removed")
Link: https://lore.kernel.org/r/2ce68694-87a7-4c06-b8a4-9870c891b580@moroto.mountain
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-11-20 11:59:23 +01:00
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
Manivannan Sadhasivam 06eea7d18f
PCI: endpoint: Add kernel-doc for pci_epc_mem_init() API
Add missing kernel-doc for pci_epc_mem_init() API.

Link: https://lore.kernel.org/linux-pci/20230717065459.14138-8-manivannan.sadhasivam@linaro.org
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
2023-08-26 16:54:46 +00:00
Manivannan Sadhasivam 127c66c3b9
PCI: epf-mhi: Use iATU for small transfers
For transfers below 4K, let's use iATU since using eDMA for such small
transfers is inefficient.

This is mainly because setting up an eDMA transfer and waiting for
completion adds some latency. This latency is negligible for large
transfers but not for the smaller ones.

With using iATU, there is an increase in ~50Mbps throughput on both MHI
UL (Uplink) and DL (Downlink) channels.

[kwilczynski: commit log]
Link: https://lore.kernel.org/linux-pci/20230717065459.14138-7-manivannan.sadhasivam@linaro.org
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
2023-08-26 16:54:46 +00:00
Manivannan Sadhasivam 8ab8a31645
PCI: epf-mhi: Add support for SM8450
Add support for Qualcomm Snapdragon SM8450 SoC to the EPF driver. SM8450
has the dedicated PID (0x0306) and supports eDMA. Currently, it has no
fixed PCI class, so it is being advertised as "PCI_CLASS_OTHERS".

Link: https://lore.kernel.org/linux-pci/20230717065459.14138-6-manivannan.sadhasivam@linaro.org
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
2023-08-26 16:54:46 +00:00
Manivannan Sadhasivam 7b99aaadda
PCI: epf-mhi: Add eDMA support
Add support for Embedded DMA (eDMA) available in the DesignWare PCIe IP
to transfer the MHI buffers between the host and the endpoint. The eDMA
use helps achieve greater throughput as the transfers are offloaded from
CPUs.

For differentiating the iATU and eDMA APIs, the pci_epf_mhi_{read/write}
APIs are renamed to pci_epf_mhi_iatu_{read/write} and separate eDMA
specific APIs pci_epf_mhi_edma_{read/write} are introduced.

Platforms that require eDMA support can pass the MHI_EPF_USE_DMA flag
through pci_epf_mhi_ep_info.

[kwilczynski: commit log]
Link: https://lore.kernel.org/linux-pci/20230717065459.14138-5-manivannan.sadhasivam@linaro.org
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
2023-08-26 16:54:45 +00:00
Manivannan Sadhasivam d9d9f26f16
PCI: epf-mhi: Make use of the alignment restriction from EPF core
Instead of hardcoding the alignment restriction in the EPF_MHI driver, make
use of the info available from the EPF core that reflects the alignment
restriction of the endpoint controller.

For this purpose, let's introduce the get_align_offset() static function.

[kwilczynski: update get_align_offset() to avoid issues on 32-bit architectures]
Link: https://lore.kernel.org/linux-pci/20230717065459.14138-3-manivannan.sadhasivam@linaro.org
Link: https://lore.kernel.org/linux-pci/20230826150626.23309-1-manivannan.sadhasivam@linaro.org
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
2023-08-26 16:54:45 +00:00
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
Rob Herring c925cfaf09 PCI: Explicitly include correct DT includes
The DT of_device.h and of_platform.h date back to the separate
of_platform_bus_type before it as merged into the regular platform bus.  As
part of that merge prepping Arm DT support 13 years ago, they "temporarily"
include each other. They also include platform_device.h and of.h. As a
result, there's a pretty much random mix of those include files used
throughout the tree. In order to detangle these headers and replace the
implicit includes with struct declarations, users need to explicitly
include the correct includes.

Link: https://lore.kernel.org/r/20230714174827.4061572-1-robh@kernel.org
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2023-07-18 14:33:17 -05:00
Linus Torvalds cff0687396 Fixes for pci_clean_master, error handling in driver inits, and various
other issues/bugs.
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Merge tag 'ntb-6.5' of https://github.com/jonmason/ntb

Pull NTB updates from Jon Mason:
 "Fixes for pci_clean_master, error handling in driver inits, and
  various other issues/bugs"

* tag 'ntb-6.5' of https://github.com/jonmason/ntb:
  ntb: hw: amd: Fix debugfs_create_dir error checking
  ntb.rst: Fix copy and paste error
  ntb_netdev: Fix module_init problem
  ntb: intel: Remove redundant pci_clear_master
  ntb: epf: Remove redundant pci_clear_master
  ntb_hw_amd: Remove redundant pci_clear_master
  ntb: idt: drop redundant pci_enable_pcie_error_reporting()
  MAINTAINERS: git://github -> https://github.com for jonmason
  NTB: EPF: fix possible memory leak in pci_vntb_probe()
  NTB: ntb_tool: Add check for devm_kcalloc
  NTB: ntb_transport: fix possible memory leak while device_register() fails
  ntb: intel: Fix error handling in intel_ntb_pci_driver_init()
  NTB: amd: Fix error handling in amd_ntb_pci_driver_init()
  ntb: idt: Fix error handling in idt_pci_driver_init()
2023-07-09 09:35:51 -07:00
ruanjinjie 956578e3d3 NTB: EPF: fix possible memory leak in pci_vntb_probe()
As ntb_register_device() don't handle error of device_register(),
if ntb_register_device() returns error in pci_vntb_probe(), name of kobject
which is allocated in dev_set_name() called in device_add() is leaked.

As comment of device_add() says, it should call put_device() to drop the
reference count that was set in device_initialize()
when it fails, so the name can be freed in kobject_cleanup().

Signed-off-by: ruanjinjie <ruanjinjie@huawei.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2023-07-08 11:02:36 -04:00
Frank Li 4ab91207fe PCI: endpoint: pci-epf-vntb: Fix typo in comments
Replace "Span" with "Spad".

Link: https://lore.kernel.org/r/20221214172254.668282-1-Frank.Li@nxp.com
Signed-off-by: Frank Li <Frank.Li@nxp.com>
Signed-off-by: Lorenzo Pieralisi <lpieralisi@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Manivannan Sadhasivam <mani@kernel.org>
2023-06-23 15:06:11 -05:00
Manivannan Sadhasivam 1bf5f25324 PCI: endpoint: Add PCI Endpoint function driver for MHI bus
Add PCI Endpoint driver for the Qualcomm MHI (Modem Host Interface) bus.

The driver implements the MHI function over PCI in the endpoint device such
as SDX55 modem. The MHI endpoint function driver acts as a controller
driver for the MHI Endpoint stack and carries out all PCI related
functionality.

Link: https://lore.kernel.org/r/20230602114756.36586-9-manivannan.sadhasivam@linaro.org
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Lorenzo Pieralisi <lpieralisi@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Kishon Vijay Abraham I <kishon@kernel.org>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
2023-06-23 15:05:49 -05:00
Manivannan Sadhasivam 6360efb96b PCI: endpoint: Add BME notifier support
Add support to notify the EPF device about the Bus Master Enable (BME)
event received by the EPC device from the Root complex.

Link: https://lore.kernel.org/r/20230602114756.36586-6-manivannan.sadhasivam@linaro.org
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Lorenzo Pieralisi <lpieralisi@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Kishon Vijay Abraham I <kishon@kernel.org>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
2023-06-23 15:05:28 -05:00
Manivannan Sadhasivam a1f6c3d7d3 PCI: endpoint: Add linkdown notifier support
Add support to notify the EPF device about the linkdown event from the EPC
device.

Link: https://lore.kernel.org/r/20230602114756.36586-5-manivannan.sadhasivam@linaro.org
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Lorenzo Pieralisi <lpieralisi@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Kishon Vijay Abraham I <kishon@kernel.org>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
2023-06-23 15:05:20 -05:00
Manivannan Sadhasivam a504c96558 PCI: endpoint: Return error if EPC is started/stopped multiple times
When the EPC is started or stopped multiple times from configfs, just
return -EALREADY. There is no need to call the EPC start/stop functions
in those cases.

Link: https://lore.kernel.org/r/20230602114756.36586-4-manivannan.sadhasivam@linaro.org
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Lorenzo Pieralisi <lpieralisi@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Kishon Vijay Abraham I <kishon@kernel.org>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
2023-06-23 15:05:11 -05:00
Manivannan Sadhasivam 081c715dfd PCI: endpoint: Pass EPF device ID to the probe function
Currently, the EPF probe function doesn't get the device ID argument needed
to correctly identify the device table ID of the EPF device.

When multiple entries are added to the "struct pci_epf_device_id" table,
the probe function needs to identify the correct one. This is achieved by
modifying the pci_epf_match_id() function to return the match ID pointer
and passing it to the driver's probe function.

pci_epf_device_match() function can return bool based on the return value
of pci_epf_match_id().

Link: https://lore.kernel.org/r/20230602114756.36586-3-manivannan.sadhasivam@linaro.org
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Lorenzo Pieralisi <lpieralisi@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Kishon Vijay Abraham I <kishon@kernel.org>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
2023-06-23 15:05:03 -05:00
Manivannan Sadhasivam ff2f19d6f1 PCI: endpoint: Add missing documentation about the MSI/MSI-X range
Both pci_epc_raise_irq() and pci_epc_map_msi_irq() APIs expect the
MSI/MSI-X vectors to start from 1 but it is not documented. Add the range
info to the kdoc of the APIs to make it clear.

Link: https://lore.kernel.org/r/20230602114756.36586-2-manivannan.sadhasivam@linaro.org
Fixes: 5e8cb40338 ("PCI: endpoint: Add EP core layer to enable EP controller and EP functions")
Fixes: 87d5972e47 ("PCI: endpoint: Add pci_epc_ops to map MSI IRQ")
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Lorenzo Pieralisi <lpieralisi@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
2023-06-23 15:04:46 -05:00
Damien Le Moal b6a6e0331f PCI: endpoint: Improve pci_epf_type_add_cfs()
pci_epf_type_add_cfs() should not be called with an unbound EPF device,
that is, an epf device with epf->driver not set. For such case, replace the
NULL return in pci_epf_type_add_cfs() with a clear ERR_PTR(-ENODEV) pointer
error return.

Link: https://lore.kernel.org/r/20230515074348.595704-2-dlemoal@kernel.org
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lpieralisi@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Manivannan Sadhasivami <manivannan.sadhasivam@linaro.org>
2023-06-23 15:04:36 -05:00
Yoshihiro Shimoda 880d51c729 PCI: endpoint: functions/pci-epf-test: Fix dma_chan direction
In pci_epf_test_init_dma_chan() epf_test->dma_chan_rx is assigned from
dma_request_channel() with DMA_DEV_TO_MEM as filter.dma_mask.

However, in pci_epf_test_data_transfer() if the dir is DMA_DEV_TO_MEM,
epf->dma_chan_rx should be used but instead we are using
epf_test->dma_chan_tx.

Fix it.

Link: https://lore.kernel.org/r/20230412063447.2841177-1-yoshihiro.shimoda.uh@renesas.com
Fixes: 8353813c88 ("PCI: endpoint: Enable DMA tests for endpoints with DMA capabilities")
Tested-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Lorenzo Pieralisi <lpieralisi@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Frank Li <Frank.Li@nxp.com>
2023-06-23 15:04:27 -05:00
Damien Le Moal 1754dfd2e7 PCI: epf-test: Simplify transfers result print
In pci_epf_test_print_rate(), instead of open coding a reduction loop to
allow for a division by a 32-bits ns value, simply use div64_u64() to
calculate the transfer rate. To match the printed unit of KB/s, this
calculation divides the rate by 1000 instead of 1024 (that would be KiB/s
unit).

Change the format of the results printed by pci_epf_test_print_rate() to be
more compact without the double new line. Also use dev_info() instead of
pr_info().

Link: https://lore.kernel.org/r/20230415023542.77601-14-dlemoal@kernel.org
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lpieralisi@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Manivannan Sadhasivam <mani@kernel.org>
2023-06-23 15:03:10 -05:00
Damien Le Moal 2566cbea69 PCI: epf-test: Simplify DMA support checks
There is no need to have each read, write and copy test functions check
for the FLAG_USE_DMA flag against the DMA support status indicated by
epf_test->dma_supported. Move this test to the command handler function
pci_epf_test_cmd_handler() to check once for all cases.

Link: https://lore.kernel.org/r/20230415023542.77601-13-dlemoal@kernel.org
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lpieralisi@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Manivannan Sadhasivam <mani@kernel.org>
2023-06-23 15:03:02 -05:00
Damien Le Moal 2eec4bec35 PCI: epf-test: Cleanup request result handling
Each of the test functions pci_epf_test_write(), pci_epf_test_read() and
pci_epf_test_copy() return an int result which is used by
pci_epf_test_cmd_handler() to set a success or error bit in the request
status.

In the spirit of keeping the processing of each test case self-contained
within its own test function, move the request status field update from
pci_epf_test_cmd_handler() to each of these test functions and change these
functions declaration to returning void.

Link: https://lore.kernel.org/r/20230415023542.77601-12-dlemoal@kernel.org
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lpieralisi@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Manivannan Sadhasivam <mani@kernel.org>
2023-06-23 15:02:49 -05:00
Damien Le Moal 96d513f5ed PCI: epf-test: Cleanup pci_epf_test_cmd_handler()
Command codes are never combined together as flags into a single value.
Thus we can replace the series of "if" tests in pci_epf_test_cmd_handler()
with a cleaner switch-case statement.  This also allows checking that we
got a valid command and print an error message if we did not.

Link: https://lore.kernel.org/r/20230415023542.77601-11-dlemoal@kernel.org
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lpieralisi@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Manivannan Sadhasivam <mani@kernel.org>
2023-06-23 15:02:39 -05:00
Damien Le Moal fc97f5f7c2 PCI: epf-test: Improve handling of command and status registers
The pci-epf-test driver uses the test register BAR memory directly to get
and execute a test registers set by the RC side and defined using a struct
pci_epf_test_reg. This direct use relies on using the register BAR address
as a pointer to a struct pci_epf_test_reg to execute the test case and to
send back the test result through the status field of struct
pci_epf_test_reg. In practice, the status field is always updated before an
interrupt is raised in pci_epf_test_raise_irq(), to ensure that the RC side
sees the updated status when receiving an interrupt.

However, such assignment direct access does not ensure that changes to the
status register make it to memory, and so visible to the host, before an
interrupt is raised, thus potentially resulting in the RC host not seeing
the correct status result for a test.

Avoid this potential problem by using READ_ONCE()/WRITE_ONCE() when
accessing the command and status fields of a pci_epf_test_reg structure.
This ensure that a test start (pci_epf_test_cmd_handler() function) and
completion (with the function pci_epf_test_raise_irq()) achieve a correct
synchronization with the MMIO register accesses on the RC host.

Link: https://lore.kernel.org/r/20230415023542.77601-10-dlemoal@kernel.org
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lpieralisi@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Manivannan Sadhasivam <mani@kernel.org>
2023-06-23 15:02:12 -05:00
Damien Le Moal 48d19fc6e4 PCI: epf-test: Simplify IRQ test commands execution
For the commands COMMAND_RAISE_LEGACY_IRQ, COMMAND_RAISE_MSI_IRQ and
COMMAND_RAISE_MSIX_IRQ, the function pci_epf_test_cmd_handler()
sets the STATUS_IRQ_RAISED status flag and calls the epc function
pci_epc_raise_irq() directly. However, this is also exactly what the
pci_epf_test_raise_irq() function does. Avoid duplicating these
operations by directly using pci_epf_test_raise_irq() for the IRQ test
commands. It is OK to do so as the host side endpoint test driver always
set the correct IRQ type for the IRQ test commands.

At the same time, move the IRQ number check done for the
COMMAND_RAISE_MSI_IRQ and COMMAND_RAISE_MSIX_IRQ commands
to pci_epf_test_raise_irq(), to also check the IRQ number requested
by the host for other test commands.

This significantly simplifies pci_epf_test_cmd_handler().

Link: https://lore.kernel.org/r/20230415023542.77601-9-dlemoal@kernel.org
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lpieralisi@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Manivannan Sadhasivam <mani@kernel.org>
2023-06-23 15:00:59 -05:00
Damien Le Moal 5444737e16 PCI: epf-test: Simplify pci_epf_test_raise_irq()
Change the interface of the function pci_epf_test_raise_irq() to directly
pass a pointer to the struct pci_epf_test_reg defining the test being
executed. This avoids the need for grabbing this pointer using the register
BAR address and simplifies the call sites as the IRQ type and IRQ numbers
do not have to be passed as arguments.

Link: https://lore.kernel.org/r/20230415023542.77601-8-dlemoal@kernel.org
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lpieralisi@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Manivannan Sadhasivam <mani@kernel.org>
2023-06-23 15:00:50 -05:00
Damien Le Moal 62d48ec7ef PCI: epf-test: Simplify read/write/copy test functions
The function pci_epf_test_cmd_handler() uses the register BAR address as a
pointer to a struct pci_epf_test_reg to determine the command sent by the
host and to execute the test function accordingly. There is no need for
doing this assignment again in each of the read, write and copy test
functions. We can simply pass the reg pointer as an argument to the
functions pci_epf_test_write(), pci_epf_test_read() and
pci_epf_test_copy().

Link: https://lore.kernel.org/r/20230415023542.77601-7-dlemoal@kernel.org
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lpieralisi@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Manivannan Sadhasivam <mani@kernel.org>
2023-06-23 15:00:40 -05:00
Damien Le Moal 349d5c840a PCI: epf-test: Use dmaengine_submit() to initiate DMA transfer
Instead of an open coded call to the tx_submit() operation of struct
dma_async_tx_descriptor, use the helper function dmaengine_submit().
No functional change is introduced with this.

Link: https://lore.kernel.org/r/20230415023542.77601-6-dlemoal@kernel.org
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lpieralisi@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Manivannan Sadhasivam <mani@kernel.org>
2023-06-23 15:00:31 -05:00
Damien Le Moal 933f31a2fe PCI: epf-test: Fix DMA transfer completion detection
pci_epf_test_data_transfer() and pci_epf_test_dma_callback() are not
handling DMA transfer completion correctly, leading to completion
notifications to the RC side that are too early. This problem can be
detected when the RC side is running an IOMMU with messages such as:

  pci-endpoint-test 0000:0b:00.0: AMD-Vi: Event logged [IO_PAGE_FAULT domain=0x001c address=0xfff00000 flags=0x0000]

When running the pcitest.sh tests: the address used for a previous
test transfer generates the above error while the next test transfer is
running.

Fix this by testing the DMA transfer status in pci_epf_test_dma_callback()
and notifying the completion only when the transfer status is DMA_COMPLETE
or DMA_ERROR. Furthermore, in pci_epf_test_data_transfer(), be paranoid and
check again the transfer status and always call dmaengine_terminate_sync()
before returning.

Link: https://lore.kernel.org/r/20230415023542.77601-5-dlemoal@kernel.org
Fixes: 8353813c88 ("PCI: endpoint: Enable DMA tests for endpoints with DMA capabilities")
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lpieralisi@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Manivannan Sadhasivam <mani@kernel.org>
Cc: stable@vger.kernel.org
2023-06-23 15:00:15 -05:00
Damien Le Moal 4aca56f8ea PCI: epf-test: Fix DMA transfer completion initialization
Reinitialize the transfer_complete DMA transfer completion before calling
tx_submit(), to avoid seeing the DMA transfer complete before the
completion is initialized, thus potentially losing the completion
notification.

Link: https://lore.kernel.org/r/20230415023542.77601-4-dlemoal@kernel.org
Fixes: 8353813c88 ("PCI: endpoint: Enable DMA tests for endpoints with DMA capabilities")
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lpieralisi@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Manivannan Sadhasivam <mani@kernel.org>
Cc: stable@vger.kernel.org
2023-06-23 15:00:01 -05:00
Damien Le Moal f6ec33979e PCI: endpoint: Move pci_epf_type_add_cfs() code
pci_epf_type_add_cfs() is called only from pci_ep_cfs_add_type_group() in
drivers/pci/endpoint/pci-ep-cfs.c, so there is no need to export this
function.  Move its code from pci-epf-core.c to pci-ep-cfs.c as a static
function.

Link: https://lore.kernel.org/r/20230415023542.77601-3-dlemoal@kernel.org
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lpieralisi@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Manivannan Sadhasivam <mani@kernel.org>
2023-06-23 14:59:38 -05:00
Damien Le Moal 70b3740f2c PCI: endpoint: Automatically create a function specific attributes group
A PCI endpoint function driver can define function specific attributes
under its function configfs directory using the add_cfs() endpoint driver
operation. This is done by tying up the mkdir operation for the function
configfs directory to a call to the add_cfs() operation.  However, there
are no checks preventing the user from repeatedly creating function
specific attribute directories with different names, resulting in the same
endpoint specific attributes group being added multiple times, which also
result in an invalid reference counting for the attribute groups. E.g.,
using the pci-epf-ntb function driver as an example, the user creates the
function as follows:

  $ modprobe pci-epf-ntb
  $ cd /sys/kernel/config/pci_ep/functions/pci_epf_ntb
  $ mkdir func0
  $ tree func0
  func0/
  |-- baseclass_code
  |-- cache_line_size
  |-- ...
  `-- vendorid

  $ mkdir func0/attrs
  $ tree func0
  func0/
  |-- attrs
  |   |-- db_count
  |   |-- mw1
  |   |-- mw2
  |   |-- mw3
  |   |-- mw4
  |   |-- num_mws
  |   `-- spad_count
  |-- baseclass_code
  |-- cache_line_size
  |-- ...
  `-- vendorid

At this point, the function can be started by linking the EP controller.
However, if the user mistakenly creates again a directory:

  $ mkdir func0/attrs2
  $ tree func0
  func0/
  |-- attrs
  |   |-- db_count
  |   |-- mw1
  |   |-- mw2
  |   |-- mw3
  |   |-- mw4
  |   |-- num_mws
  |   `-- spad_count
  |-- attrs2
  |   |-- db_count
  |   |-- mw1
  |   |-- mw2
  |   |-- mw3
  |   |-- mw4
  |   |-- num_mws
  |   `-- spad_count
  |-- baseclass_code
  |-- cache_line_size
  |-- ...
  `-- vendorid

The endpoint function specific attributes are duplicated and cause a crash
when the endpoint function device is torn down:

  refcount_t: addition on 0; use-after-free.
  WARNING: CPU: 2 PID: 834 at lib/refcount.c:25 refcount_warn_saturate+0xc8/0x144
  CPU: 2 PID: 834 Comm: rmdir Not tainted 6.3.0-rc1 #1
  Hardware name: Pine64 RockPro64 v2.1 (DT)
  pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
  ...
  Call trace:
  refcount_warn_saturate+0xc8/0x144
  config_item_get+0x7c/0x80
  configfs_rmdir+0x17c/0x30c
  vfs_rmdir+0x8c/0x204
  do_rmdir+0x158/0x184
  __arm64_sys_unlinkat+0x64/0x80
  invoke_syscall+0x48/0x114
  ...

Fix this by modifying pci_epf_cfs_work() to execute the new function
pci_ep_cfs_add_type_group() which itself calls pci_epf_type_add_cfs() to
obtain the function specific attribute group and the group name (directory
name) from the endpoint function driver. If the function driver defines an
attribute group, pci_ep_cfs_add_type_group() then proceeds to register this
group using configfs_register_group(), thus automatically exposing the
function type specific configfs attributes to the user. E.g.:

  $ modprobe pci-epf-ntb
  $ cd /sys/kernel/config/pci_ep/functions/pci_epf_ntb
  $ mkdir func0
  $ tree func0
  func0/
  |-- baseclass_code
  |-- cache_line_size
  |-- ...
  |-- pci_epf_ntb.0
  |   |-- db_count
  |   |-- mw1
  |   |-- mw2
  |   |-- mw3
  |   |-- mw4
  |   |-- num_mws
  |   `-- spad_count
  |-- primary
  |-- ...
  `-- vendorid

With this change, there is no need for the user to create or delete
directories in the endpoint function attributes directory. The
pci_epf_type_group_ops group operations are thus removed.

Also update the documentation for the pci-epf-ntb and pci-epf-vntb function
drivers to reflect this change, removing the explanations showing the need
to manually create the sub-directory for the function specific attributes.

Link: https://lore.kernel.org/r/20230415023542.77601-2-dlemoal@kernel.org
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lpieralisi@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Manivannan Sadhasivam <mani@kernel.org>
2023-06-23 14:57:59 -05:00
Shunsuke Mie 37587673cd PCI: endpoint: Fix a Kconfig prompt of vNTB driver
vNTB driver and NTB driver have same Kconfig prompt. Changed to make it
distinguishable.

Link: https://lore.kernel.org/r/20230202103832.2038286-1-mie@igel.co.jp
Fixes: e35f56bb03 ("PCI: endpoint: Support NTB transfer between RC and EP")
Signed-off-by: Shunsuke Mie <mie@igel.co.jp>
Signed-off-by: Lorenzo Pieralisi <lpieralisi@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Manivannan Sadhasivam <mani@kernel.org>
2023-06-23 14:57:47 -05:00
Greg Kroah-Hartman 1aaba11da9 driver core: class: remove module * from class_create()
The module pointer in class_create() never actually did anything, and it
shouldn't have been requred to be set as a parameter even if it did
something.  So just remove it and fix up all callers of the function in
the kernel tree at the same time.

Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Acked-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Link: https://lore.kernel.org/r/20230313181843.1207845-4-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-03-17 15:16:33 +01:00
Bjorn Helgaas 3eb5d0f26f Merge branch 'pci/misc'
- Drop bogus kernel-doc marker in pci_endpoint_test.c (Randy Dunlap)

- Fix epf_ntb_mw_bar_clear() kernel-doc (Yang Yingliang)

- Constify struct kobj_type pci_slot_ktype (Thomas Weißschuh)

* pci/misc:
  PCI: hv: Drop duplicate PCI_MSI dependency
  PCI/sysfs: Constify struct kobj_type pci_slot_ktype
  PCI: endpoint: pci-epf-vntb: Add epf_ntb_mw_bar_clear() num_mws kernel-doc
  misc: pci_endpoint_test: Drop initial kernel-doc marker
2023-02-22 13:47:32 -06:00
Bjorn Helgaas 33abd97c34 Merge branch 'pci/endpoint'
- Convert dra7xx to threaded IRQ handler (Manivannan Sadhasivam)

- Move tegra194 dw_pcie_ep_linkup() to threaded IRQ handler (Manivannan
  Sadhasivam)

- Add a separate lock for the endpoint pci_epf list to avoid deadlock
  while running callbacks (Manivannan Sadhasivam)

- Use callbacks instead of notifier chains to signal events from EPC to EPF
  drivers (Manivannan Sadhasivam)

- Use link_up() callback in place of LINK_UP notifier (Manivannan
  Sadhasivam)

* pci/endpoint:
  PCI: endpoint: Use link_up() callback in place of LINK_UP notifier
  PCI: endpoint: Use callback mechanism for passing events from EPC to EPF
  PCI: endpoint: Use a separate lock for protecting epc->pci_epf list
  PCI: tegra194: Move dw_pcie_ep_linkup() to threaded IRQ handler
  PCI: dra7xx: Use threaded IRQ handler for "dra7xx-pcie-main" IRQ
2023-02-22 13:47:28 -06:00
Nick Alcock f98954b293 PCI: Remove MODULE_LICENSE so boolean drivers don't look like modules
Since 8b41fc4454 ("kbuild: create modules.builtin without
Makefile.modbuiltin or tristate.conf"), MODULE_LICENSE declarations are
used to identify modules. As a consequence, MODULE_LICENSE in non-modules
causes modprobe to misidentify the object file as a module when it is not,
and modprobe might succeed rather than failing with a suitable error
message.

For tristate modules that can be either built-in or loaded at runtime,
modprobe succeeds in both cases:

  # modprobe ext4
  [exit status zero if CONFIG_EXT4_FS=y or =m]

For boolean modules like the Standard Hot Plug Controller driver (shpchp)
that cannot be loaded at runtime, modprobe should always fail like this:

  # modprobe shpchp
  modprobe: FATAL: Module shpchp not found in directory /lib/modules/...
  [exit status non-zero regardless of CONFIG_HOTPLUG_PCI_SHPC]

but prior to this commit, shpchp_core.c contained MODULE_LICENSE, so
"modprobe shpchp" silently succeeded when it should have failed.

Remove MODULE_LICENSE in files that cannot be built as modules.

[bhelgaas: commit log, squash]
Suggested-by: Luis Chamberlain <mcgrof@kernel.org>
Link: https://lore.kernel.org/r/20230216152410.4312-1-nick.alcock@oracle.com/
Signed-off-by: Nick Alcock <nick.alcock@oracle.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Hitomi Hasegawa <hasegawa-hitomi@fujitsu.com>
Cc: Rob Herring <robh@kernel.org>
Cc: Lorenzo Pieralisi <lpieralisi@kernel.org>
2023-02-17 08:47:58 -06:00
Manivannan Sadhasivam f5edd8715e
PCI: endpoint: Use link_up() callback in place of LINK_UP notifier
As a part of the transition towards callback mechanism for signalling the
events from EPC to EPF, let's use the link_up() callback in the place of
the LINK_UP notifier. This also removes the notifier support completely
from the PCI endpoint framework.

Link: https://lore.kernel.org/linux-pci/20230124071158.5503-6-manivannan.sadhasivam@linaro.org
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
Acked-by: Kishon Vijay Abraham I <kishon@kernel.org>
2023-02-14 07:27:32 +09:00
Manivannan Sadhasivam 838125b07e
PCI: endpoint: Use callback mechanism for passing events from EPC to EPF
Instead of using the notifiers for passing the events from EPC to EPF,
let's introduce a callback based mechanism where the EPF drivers can
populate relevant callbacks for EPC events they want to subscribe.

The use of notifiers in kernel is not recommended if there is a real link
between the sender and receiver, like in this case. Also, the existing
atomic notifier forces the notification functions to be in atomic context
while the caller may be in non-atomic context. For instance, the two
in-kernel users of the notifiers, pcie-qcom and pcie-tegra194, both are
calling the notifier functions in non-atomic context (from threaded IRQ
handlers). This creates a sleeping in atomic context issue with the
existing EPF_TEST driver that calls the EPC APIs that may sleep.

For all these reasons, let's get rid of the notifier chains and use the
simple callback mechanism for signalling the events from EPC to EPF
drivers. This preserves the context of the caller and avoids the latency
of going through a separate interface for triggering the notifications.

As a first step of the transition, the core_init() callback is introduced
in this commit, that'll replace the existing CORE_INIT notifier used for
signalling the init complete event from EPC.

During the occurrence of the event, EPC will go over the list of EPF
drivers attached to it and will call the core_init() callback if available.

Link: https://lore.kernel.org/linux-pci/20230124071158.5503-5-manivannan.sadhasivam@linaro.org
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
Acked-by: Kishon Vijay Abraham I <kishon@kernel.org>
2023-02-14 07:27:25 +09:00
Manivannan Sadhasivam d6dd5bafaa
PCI: endpoint: Use a separate lock for protecting epc->pci_epf list
The EPC controller maintains a list of EPF drivers added to it. For
protecting this list against the concurrent accesses, the epc->lock
(used for protecting epc_ops) has been used so far. Since there were
no users trying to use epc_ops and modify the pci_epf list simultaneously,
this was not an issue.

But with the addition of callback mechanism for passing the events, this
will be a problem. Because the pci_epf list needs to be iterated first
for getting hold of the EPF driver and then the relevant event specific
callback needs to be called for the driver.

If the same epc->lock is used, then it will result in a deadlock scenario.

For instance,

...
	mutex_lock(&epc->lock);
	list_for_each_entry(epf, &epc->pci_epf, list) {
		epf->event_ops->core_init(epf);
		|
		|-> pci_epc_set_bar();
			|
			|-> mutex_lock(&epc->lock) # DEADLOCK
...

So to fix this issue, use a separate lock called "list_lock" for
protecting the pci_epf list against the concurrent accesses. This lock
will also be used by the callback mechanism.

Link: https://lore.kernel.org/linux-pci/20230124071158.5503-4-manivannan.sadhasivam@linaro.org
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
Acked-by: Kishon Vijay Abraham I <kishon@ti.com>
2023-02-14 07:27:15 +09:00
Yang Yingliang fd858402c6 PCI: endpoint: pci-epf-vntb: Add epf_ntb_mw_bar_clear() num_mws kernel-doc
8e4bfbe644 ("PCI: endpoint: pci-epf-vntb: fix error handle in
epf_ntb_mw_bar_init()") added a "num_mws" parameter to
epf_ntb_mw_bar_clear() but failed to add kernel-doc for num_mws.

Add kernel-doc for num_mws on epf_ntb_mw_bar_clear().

Fixes: 8e4bfbe644 ("PCI: endpoint: pci-epf-vntb: fix error handle in epf_ntb_mw_bar_init()")
Link: https://lore.kernel.org/r/20230103024907.293853-1-yangyingliang@huawei.com
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2023-01-18 14:14:04 -06:00
Bjorn Helgaas bcccaa0a48 Merge branch 'remotes/lorenzo/pci/misc'
- Register notifier if core_init_notifier is enabled in pci-epf-test
  (Kunihiko Hayashi)

- Fixup Kconfig indentation (Shunsuke Mie)

* remotes/lorenzo/pci/misc:
  PCI: endpoint: Fix Kconfig indent style
  PCI: pci-epf-test: Register notifier if only core_init_notifier is enabled
2022-12-10 10:36:40 -06:00
Frank Li 5f697b2500 PCI: endpoint: pci-epf-vntb: Fix sparse ntb->reg build warning
pci-epf-vntb.c:1128:33: sparse:     expected void [noderef] __iomem *base
  pci-epf-vntb.c:1128:33: sparse:     got struct epf_ntb_ctrl *reg

Add __iomem type cast in vntb_epf_peer_spad_read() and
vntb_epf_peer_spad_write().

Link: https://lore.kernel.org/r/20221102141014.1025893-8-Frank.Li@nxp.com
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Frank Li <frank.li@nxp.com>
Signed-off-by: Lorenzo Pieralisi <lpieralisi@kernel.org>
Acked-by: Manivannan Sadhasivam <mani@kernel.org>
2022-11-23 18:09:20 +01:00