PCI: endpoint: Refactor pci_epf_alloc_space() API

Refactor pci_epf_alloc_space() API to accept "epc_features" as a parameter.
This is a preparatory work to make the API more robust.

Reviewed-by: Fr

PCI: endpoint: Refactor pci_epf_alloc_space() API

Refactor pci_epf_alloc_space() API to accept "epc_features" as a parameter.
This is a preparatory work to make the API more robust.

Reviewed-by: Frank Li <Frank.Li@nxp.com>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Niklas Cassel <cassel@kernel.org>
Link: https://lore.kernel.org/r/20240207213922.1796533-2-cassel@kernel.org
[mani: reworded commit message]
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>

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PCI: Fix kernel-doc issues

Fix kernel-doc issues reported by
"find include -name \*pci\* | xargs scripts/kernel-doc -none":

include/linux/pci.h:731: warning: Function parameter or member 'pdev' n

PCI: Fix kernel-doc issues

Fix kernel-doc issues reported by
"find include -name \*pci\* | xargs scripts/kernel-doc -none":

include/linux/pci.h:731: warning: Function parameter or member 'pdev' not described in 'pci_is_vga'
include/linux/pci-epc.h:154: warning: Function parameter or member 'list_lock' not described in 'pci_epc'
include/linux/pci-epf.h:83: warning: expecting prototype for struct pci_epf_event_ops. Prototype was for struct pci_epc_event_ops instead

Link: https://lore.kernel.org/r/20240111162850.2177655-1-helgaas@kernel.org
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Sui Jingfeng <suijingfeng@loongson.cn>

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PCI: endpoint: Make struct pci_epf_ops in pci_epf_driver const

The pci_epf_ops struct contains a set of callbacks that are used by the
pci_epf_driver, and is never modified by the EPF core itself.

PCI: endpoint: Make struct pci_epf_ops in pci_epf_driver const

The pci_epf_ops struct contains a set of callbacks that are used by the
pci_epf_driver, and is never modified by the EPF core itself.

Marking the struct pointer const allows EPF drivers to declare their
pci_epf_ops struct to be const.

This allows the struct to be placed in the read-only section. Which
for example brings some security benefits as the callbacks can not be
overwritten.

[kwilczynski: commit log]
Link: https://lore.kernel.org/linux-pci/20230722230848.589428-1-lars@metafoo.de
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
Reviewed-by: Manivannan Sadhasivam <mani@kernel.org>

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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/

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>

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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.sad

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>

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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

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>

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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
functi

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>

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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

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>

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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 E

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>

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PCI: endpoint: Add support to add virtual function in endpoint core

Add support to add virtual function in endpoint core. The virtual
function can only be associated with a physical function instead

PCI: endpoint: Add support to add virtual function in endpoint core

Add support to add virtual function in endpoint core. The virtual
function can only be associated with a physical function instead of a
endpoint controller. Provide APIs to associate a virtual function with
a physical function here.

[weiyongjun1@huawei.com: PCI: endpoint: Fix missing unlock on error in
pci_epf_add_vepf() - Reported-by: Hulk Robot <hulkci@huawei.com>]

Link: https://lore.kernel.org/r/20210819123343.1951-3-kishon@ti.com
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>

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PCI: endpoint: Make struct pci_epf_driver::remove return void

The driver core ignores the return value of pci_epf_device_remove()
(because there is only little it can do when a device disappears) an

PCI: endpoint: Make struct pci_epf_driver::remove return void

The driver core ignores the return value of pci_epf_device_remove()
(because there is only little it can do when a device disappears) and
there are no pci_epf_drivers with a remove callback.

So make it impossible for future drivers to return an unused error code
by changing the remove prototype to return void.

The real motivation for this change is the quest to make struct
bus_type::remove return void, too.

Acked-by: Kishon Vijay Abraham I <kishon@ti.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20210713193522.1770306-2-u.kleine-koenig@pengutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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PCI: Fix kernel-doc formatting

Fix kernel-doc formatting throughout drivers/pci and related include files.
No change to functionality intended.

Check for warnings:

$ find include drivers/pci -ty

PCI: Fix kernel-doc formatting

Fix kernel-doc formatting throughout drivers/pci and related include files.
No change to functionality intended.

Check for warnings:

$ find include drivers/pci -type f -path "*pci*.[ch]" | xargs scripts/kernel-doc -none

[bhelgaas: squashed to one commit]
Link: https://lore.kernel.org/r/20210509030237.368540-1-kw@linux.com
Link: https://lore.kernel.org/r/20210703151306.1922450-1-kw@linux.com
Link: https://lore.kernel.org/r/20210703151306.1922450-2-kw@linux.com
Link: https://lore.kernel.org/r/20210703151306.1922450-3-kw@linux.com
Link: https://lore.kernel.org/r/20210703151306.1922450-4-kw@linux.com
Link: https://lore.kernel.org/r/20210703151306.1922450-5-kw@linux.com
Signed-off-by: Krzysztof Wilczyński <kw@linux.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

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PCI: endpoint: Allow user to create sub-directory of 'EPF Device' directory

Documentation/PCI/endpoint/pci-endpoint-cfs.rst explains how a user has to
create a directory in-order to create a 'EPF De

PCI: endpoint: Allow user to create sub-directory of 'EPF Device' directory

Documentation/PCI/endpoint/pci-endpoint-cfs.rst explains how a user has to
create a directory in-order to create a 'EPF Device' that can be
configured/probed by 'EPF Driver'.

Allow user to create a sub-directory of 'EPF Device' directory for any
function specific attributes that has to be exposed to the user.

Link: https://lore.kernel.org/r/20210201195809.7342-11-kishon@ti.com
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

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PCI: endpoint: Add pci_epf_ops to expose function-specific attrs

In addition to the attributes that are generic across function drivers
documented in Documentation/PCI/endpoint/pci-endpoint-cfs.rst,

PCI: endpoint: Add pci_epf_ops to expose function-specific attrs

In addition to the attributes that are generic across function drivers
documented in Documentation/PCI/endpoint/pci-endpoint-cfs.rst, there could
be function-specific attributes that has to be exposed by the function
driver to be configured by the user. Add ->add_cfs() in pci_epf_ops to be
populated by the function driver if it has to expose any function-specific
attributes and pci_epf_type_add_cfs() to be invoked by pci-ep-cfs.c when
sub-directory to main function directory is created.

Link: https://lore.kernel.org/r/20210201195809.7342-10-kishon@ti.com
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

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PCI: endpoint: Add support to associate secondary EPC with EPF

In the case of standard endpoint functions, only one endpoint controller
(EPC) will be associated with an endpoint function (EPF). Howe

PCI: endpoint: Add support to associate secondary EPC with EPF

In the case of standard endpoint functions, only one endpoint controller
(EPC) will be associated with an endpoint function (EPF). However for
providing NTB (non transparent bridge) functionality, two EPCs should be
associated with a single EPF. Add support to associate secondary EPC with
EPF. This is in preparation for adding NTB endpoint function driver.

Link: https://lore.kernel.org/r/20210201195809.7342-7-kishon@ti.com
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

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PCI: endpoint: Remove unused pci_epf_match_device()

Remove unused pci_epf_match_device() function added in pci-epf-core.c

Link: https://lore.kernel.org/r/20210201195809.7342-6-kishon@ti.com
Signed-

PCI: endpoint: Remove unused pci_epf_match_device()

Remove unused pci_epf_match_device() function added in pci-epf-core.c

Link: https://lore.kernel.org/r/20210201195809.7342-6-kishon@ti.com
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

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PCI: endpoint: Make *_free_bar() to return error codes on failure

Modify pci_epc_get_next_free_bar() and pci_epc_get_first_free_bar() to
return error values if there are no free BARs available.

Lin

PCI: endpoint: Make *_free_bar() to return error codes on failure

Modify pci_epc_get_next_free_bar() and pci_epc_get_first_free_bar() to
return error values if there are no free BARs available.

Link: https://lore.kernel.org/r/20210201195809.7342-5-kishon@ti.com
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

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PCI: dwc: Fix dw_pcie_ep_raise_msix_irq() to get correct MSI-X table address

commit beb4641a787d ("PCI: dwc: Add MSI-X callbacks handler"),
in order to raise MSI-X interrupt, obtained MSIX table add

PCI: dwc: Fix dw_pcie_ep_raise_msix_irq() to get correct MSI-X table address

commit beb4641a787d ("PCI: dwc: Add MSI-X callbacks handler"),
in order to raise MSI-X interrupt, obtained MSIX table address from
Base Address Register (BAR). However BAR only holds PCI address
programmed by the host whereas the MSI-X table should be in the local
memory.

Store the MSI-X table address (virtual address) as part of ->set_bar()
callback and use that to get the message address and message data
here.

Fixes: beb4641a787d ("PCI: dwc: Add MSI-X callbacks handler")
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>

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PCI: endpoint: Add notification for core init completion

Add support to send notifications to EPF from EPC once the core
registers initialization is complete.

Signed-off-by: Vidya Sagar <vidyas@nvi

PCI: endpoint: Add notification for core init completion

Add support to send notifications to EPF from EPC once the core
registers initialization is complete.

Signed-off-by: Vidya Sagar <vidyas@nvidia.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Kishon Vijay Abraham I <kishon@ti.com>

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PCI: endpoint: Protect concurrent access to pci_epf_ops with mutex

Protect concurrent access to pci_epf_ops with a mutex.

Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Lorenz

PCI: endpoint: Protect concurrent access to pci_epf_ops with mutex

Protect concurrent access to pci_epf_ops with a mutex.

Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>

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PCI: endpoint: Use notification chain mechanism to notify EPC events to EPF

Use atomic_notifier_call_chain() to notify EPC events like linkup to EPF
driver instead of using linkup ops in EPF driver.

PCI: endpoint: Use notification chain mechanism to notify EPC events to EPF

Use atomic_notifier_call_chain() to notify EPC events like linkup to EPF
driver instead of using linkup ops in EPF driver. This is in preparation
for adding proper locking mechanism to EPF ops. This will also enable to
add more events (in addition to linkup) in the future.

Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Tested-by: Vidya Sagar <vidyas@nvidia.com>

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PCI: endpoint: Add support to specify alignment for buffers allocated to BARs

The address that is allocated using pci_epf_alloc_space() is
directly written to the target address of the Inbound Addre

PCI: endpoint: Add support to specify alignment for buffers allocated to BARs

The address that is allocated using pci_epf_alloc_space() is
directly written to the target address of the Inbound Address
Translation unit (ie the HW component implementing inbound address
decoding) on endpoint controllers.

Designware IP [1] has a configuration parameter (CX_ATU_MIN_REGION_SIZE
[2]) which has 64KB as default value and the lower 16 bits of the Base,
Limit and Target registers of the Inbound ATU are fixed to zero. If the
programmed memory address is not aligned to 64 KB boundary this causes
memory corruption.

Modify pci_epf_alloc_space() API to take alignment size as argument in
order to allocate buffers to be mapped to BARs with an alignment that
suits the platform where they are used.

Add an 'align' parameter to epc_features which can be used by platform
drivers to specify the BAR allocation alignment requirements and use
this while invoking pci_epf_alloc_space().

[1] "I/O and MEM Match Modes" section in DesignWare Cores PCI Express
Controller Databook version 4.90a
[2] http://www.ti.com/lit/ug/spruid7c/spruid7c.pdf

Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>

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PCI: endpoint: Add MSI-X interfaces

Add PCI_EPC_IRQ_MSIX type.

Add MSI-X callbacks signatures to the ops structure.

Add sysfs interface for set/get MSI-X capability maximum number.

Update documen

PCI: endpoint: Add MSI-X interfaces

Add PCI_EPC_IRQ_MSIX type.

Add MSI-X callbacks signatures to the ops structure.

Add sysfs interface for set/get MSI-X capability maximum number.

Update documentation accordingly.

Signed-off-by: Gustavo Pimentel <gustavo.pimentel@synopsys.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Kishon Vijay Abraham I <kishon@ti.com>

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PCI: endpoint: Create configfs entry for each pci_epf_device_id table entry

In order to be able to provide correct driver_data for pci_epf device,
a separate configfs entry for each pci_epf_device_i

PCI: endpoint: Create configfs entry for each pci_epf_device_id table entry

In order to be able to provide correct driver_data for pci_epf device,
a separate configfs entry for each pci_epf_device_id table entry in
pci_epf_driver is required.

Add support to create configfs entry for each pci_epf_device_id
table entry here.

Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Tested-by: Gustavo Pimentel <gustavo.pimentel@synopsys.com>

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PCI: endpoint: Simplify epc->ops->set_bar()/pci_epc_set_bar()

Add barno and flags to struct epf_bar.
That way we can simplify epc->ops->set_bar()/pci_epc_set_bar()
by passing a struct *epf_bar inste

PCI: endpoint: Simplify epc->ops->set_bar()/pci_epc_set_bar()

Add barno and flags to struct epf_bar.
That way we can simplify epc->ops->set_bar()/pci_epc_set_bar()
by passing a struct *epf_bar instead of a whole lot of arguments.

This is needed so that epc->ops->set_bar() implementations can
modify BAR flags. Will be utilized in a succeeding patch.

Signed-off-by: Niklas Cassel <niklas.cassel@axis.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Gustavo Pimentel <gustavo.pimentel@synopsys.com>
Acked-by: Kishon Vijay Abraham I <kishon@ti.com>

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