Currently clp_set_pci_fn() always returns 0 as long as the CLP request
itself succeeds even if the operation itself returns a response code
other than CLP_RC_OK or CLP_RC_SETPCIFN_ALRDY. This is highly misleading
because calling code assumes that a zero rc means that the operation was
successful.

Fix this by returning the response code or cc on failure with the
exception of the special handling for CLP_RC_SETPCIFN_ALRDY. Also let's
not assume that the returned function handle for CLP_RC_SETPCIFN_ALRDY
is 0, we don't need it anyway.
Reviewed-by: NMatthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: NNiklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: NHeiko Carstens <hca@linux.ibm.com>

It's currently safe to call zpci_cleanup_bus_resources() even if the
resources were never created but it makes no sense so check
zdev->has_resources before we call zpci_cleanup_bus_resources() in
zpci_release_device().
Reviewed-by: NMatthew Rosato <mjrosato@linux.ibm.com>
Acked-by: NPierre Morel <pmorel@linux.ibm.com>
Signed-off-by: NNiklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: NHeiko Carstens <hca@linux.ibm.com>

Kernel support for the newer PCI mio instructions can be toggled off
with the pci=nomio command line option which needs to integrate with
common code PCI option parsing. However this option then toggles static
branches which can't be toggled yet in an early_param() call.

Thus commit 9964f396 ("s390: fix setting of mio addressing control")
moved toggling the static branches to the PCI init routine.

With this setup however we can't check for mio support outside the PCI
code during early boot, i.e. before switching the static branches, which
we need to be able to export this as an ELF HWCAP.

Improve on this by turning mio availability into a machine flag that
gets initially set based on CONFIG_PCI and the facility bit and gets
toggled off if pci=nomio is found during PCI option parsing allowing
simple access to this machine flag after early init.
Reviewed-by: NHeiko Carstens <hca@linux.ibm.com>
Signed-off-by: NNiklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: NHeiko Carstens <hca@linux.ibm.com>

With zpci_configure_device() now always called on a device that has
already been configured on the platform level its name has become
misleading. Rename it to zpci_scan_configured_device() to signify that
the function now only handles the correct scanning of a newly configured
PCI function taking care of the special handling necessary for function
0 and functions parked waiting for a PCI bus that can't be created
without first seeing function 0.
Reviewed-by: NMatthew Rosato <mjrosato@linux.ibm.com>
Reviewed-by: NPierre Morel <pmorel@linux.ibm.com>
Signed-off-by: NNiklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: NHeiko Carstens <hca@linux.ibm.com>

Currently zpci_configure_device() can be called on a zPCI function in
two completely different states. Either the underlying zPCI function has
already been configured by the platform and we are only doing the
scanning to get it usable by Linux drivers. Or the underlying function
is in Standby and we first do an SCLP to get it configured. This makes
zpci_configure_device() harder to reason about. Since calling
zpci_configure_device() on a function in Standby only happens in
enable_slot() simply pull out the SCLP call and setting of zdev->state
and thus call zpci_configure_device() under the same circumstances as
in the event handling code.
Reviewed-by: NMatthew Rosato <mjrosato@linux.ibm.com>
Reviewed-by: NPierre Morel <pmorel@linux.ibm.com>
Signed-off-by: NNiklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: NHeiko Carstens <hca@linux.ibm.com>

Now that the zbus can be created without being scanned we can go one
step further and make registering a device to a zbus independent from
scanning it. This way the zbus handling becomes much more natural
in that functions can be registered on the zbus to be scanned later more
closely resembling the handling of both real PCI hardware and other
virtual PCI busses like Hyper-V's virtual PCI bus (see for example
drivers/pci/controller/pci-hyperv.c:create_root_hv_pci_bus()).

Having zbus registration separate from scanning allows us to return
fully initialized but still disabled zdevs from zpci_create_device()
which can then be configured just as we would configure a zdev from
standby (minus the SCLP Configure already done by the platform).  There
is still the exception that a PCI function with non-zero devfn can be
plugged before its PCI bus, which depends on the function with zero
devfn, is created. In this case the zdev returend from
zpci_create_device() is still missing its bus, hotplug slot, and
resources which need to be created later but at least it doesn't wait in
the enabled state and can otherwise be treated as initialized.

With this we also separate the initial PCI scan using CLP List PCI
Functions into two phases. In the CLP loop's callback we only register
each function with a virtual zbus creating the latter as needed. Then,
after we have built this virtual PCI topology based on our list of
zbusses, we can make use of the common code functionality to scan each
complete zbus as a separate child bus.
Reviewed-by: NMatthew Rosato <mjrosato@linux.ibm.com>
Acked-by: NPierre Morel <pmorel@linux.ibm.com>
Signed-off-by: NNiklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: NHeiko Carstens <hca@linux.ibm.com>

In the existing code the creation of the PCI bus and the scanning of
function zero all happens in zpci_scan_bus(). This in turn requires
functions to be enabled and their resources to be available before the
PCI bus is even created.

This not only means that functions are enabled long before they are
actually made available to the common PCI subsystem. In case of
functions with non-zero devfn which appeared before the function with
devfn zero they can wait arbitrarily long in this enabled but not
scanned state.

Fix this by separating the creation of the PCI bus from scanning it and
only prepare, that is enable and setup MMIO bus resources, functions
just before they are scanned. As they may be scanned multiple times
track if we already created resources in the zdev.
Reviewed-by: NMatthew Rosato <mjrosato@linux.ibm.com>
Acked-by: NPierre Morel <pmorel@linux.ibm.com>
Signed-off-by: NNiklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: NHeiko Carstens <hca@linux.ibm.com>

To match zpci_bus_scan_device() and the PCI common code terminology and
to remove some code duplication, we pull the multiple uses of
pci_scan_single_device() into a function. For now this has the side
effect of adding each device to the PCI bus separately and locking and
unlocking the rescan/remove lock for each instead of just once per bus.
This is clearly less efficient but provides a correct intermediate
behavior until a follow on change does both the adding and scanning only
once per bus.
Reviewed-by: NMatthew Rosato <mjrosato@linux.ibm.com>
Acked-by: NPierre Morel <pmorel@linux.ibm.com>
Signed-off-by: NNiklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: NHeiko Carstens <hca@linux.ibm.com>

The zpci_remove_device() function removes the device from the PCI common
code core which is an operation dealing primarily with the zbus and PCI
bus code. With that and to match an upcoming refactoring of the
symmetric scanning part move it to the bus code.
Reviewed-by: NMatthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: NNiklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: NHeiko Carstens <hca@linux.ibm.com>

A zPCI event with PEC 0x0301 for an existing zPCI device goes through
the same actions as enable_slot(). Similarly a zPCI event with PEC
0x0303 does the same steps as disable_slot().
We can thus unify both actions as zpci_configure_device() respectively
zpci_deconfigure_device().
Reviewed-by: NMatthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: NNiklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: NHeiko Carstens <hca@linux.ibm.com>

When zpci_release_device() is called on a zPCI function that is still
configured it would not be deconfigured. Until now this hasn't caused
any problems because zpci_zdev_put() is only ever called for devices
in Standby or Reserved. Fix it by adding sclp_pci_deconfigure() to the
switch when in Configured state.
Reviewed-by: NMatthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: NNiklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: NHeiko Carstens <hca@linux.ibm.com>

The current zdev->state mixes the configuration states supported by CLP
with an additional Online state which is used inconsistently to include
enabled zPCI functions which are not yet visible to the common PCI
subsytem. In preparation for a clean separation between architected
configuration states and fine grained function states remove the Online
function state.

Where we previously checked for Online it is more accurate to check if
the function is enabled to avoid an edge case where a disabled device
was still treated as Online. This also simplifies checks whether
a function is configured as this is now directly reflected by its
function state.
Reviewed-by: NMatthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: NNiklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: NHeiko Carstens <hca@linux.ibm.com>

In commit 05bc1be6 ("s390/pci: create zPCI bus") we removed the
pci_dev_put() call matching the earlier pci_get_slot() done as part of
__zpci_event_availability(). This was based on the wrong understanding
that the device_put() done as part of pci_destroy_device() would counter
the pci_get_slot() when it only counters the initial reference. This
same understanding and existing bad example also lead to not doing
a pci_dev_put() in zpci_remove_device().

Since releasing the PCI devices, unlike releasing the PCI slot, does not
print any debug message for testing I added one in pci_release_dev().
This revealed that we are indeed leaking the PCI device on PCI
hotunplug. Further testing also revealed another missing pci_dev_put() in
disable_slot().

Fix this by adding the missing pci_dev_put() in disable_slot() and fix
zpci_remove_device() with the correct pci_dev_put() calls. Also instead
of calling pci_get_slot() in __zpci_event_availability() to determine if
a PCI device is registered and then doing the same again in
zpci_remove_device() do this once in zpci_remove_device() which makes
sure that the pdev in __zpci_event_availability() is only used for the
result of pci_scan_single_device() which does not need a reference count
decremnt as its ownership goes to the PCI bus.

Also move the check if zdev->zbus->bus is set into zpci_remove_device()
since it may be that we're removing a device with devfn != 0 which never
had a PCI bus. So we can still set the pdev->error_state to indicate
that the device is not usable anymore, add a flag to set the error state.

Fixes: 05bc1be6 ("s390/pci: create zPCI bus")
Cc: <stable@vger.kernel.org> # 5.8+: e1bff843 s390/pci: remove superfluous zdev->zbus check
Cc: <stable@vger.kernel.org> # 5.8+: ba764dd7 s390/pci: refactor zpci_create_device()
Cc: <stable@vger.kernel.org> # 5.8+
Reviewed-by: NMatthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: NNiklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: NHeiko Carstens <hca@linux.ibm.com>

Currently zpci_create_device() is only called in clp_add_pci_device()
which allocates the memory for the struct zpci_dev being created. There
is little separation of concerns as only both functions together can
create a zpci_dev and the only CLP specific code in
clp_add_pci_device() is a call to clp_query_pci_fn().

Improve this by removing clp_add_pci_device() and refactor
zpci_create_device() such that it alone creates and initializes the
zpci_dev given the FID and Function Handle. For this we need to make
clp_query_pci_fn() non-static. While at it remove the function handle
parameter since we can just take that from the zpci_dev. Also move
adding to the zpci_list to after the zdev has been fully created which
eliminates a window where a partially initialized zdev can be found by
get_zdev_by_fid().
Acked-by: NPierre Morel <pmorel@linux.ibm.com>
Signed-off-by: NNiklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: NVasily Gorbik <gor@linux.ibm.com>

when we're missing the necessary machine facilities zPCI can
not function. Until now it would silently fail to be initialized,
add an informational print.
Signed-off-by: NNiklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: NHeiko Carstens <hca@linux.ibm.com>

the only caller of this was removed as part of the suspend/resume
removal so no need to keep this function around.
Reviewed-by: NMatthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: NNiklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: NVasily Gorbik <gor@linux.ibm.com>

currently we have multiple #ifdef CONFIG_PCI_IOV blocks spread over
different compliation units and headers, all dealing with SR-IOV
specific behavior.
This violates the style guide which discourages conditionally compiled
code blocks and hinders maintainability by speading SR-IOV functionality
over many files.

Let's move all of this into a conditionally compiled pci_iov.c file and
local header and prefix SR-IOV specific functions with zpci_iov_*.
Reviewed-by: NMatthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: NNiklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: NVasily Gorbik <gor@linux.ibm.com>

With our current support for the new MIO PCI instructions, write
combining/write back MMIO memory can be obtained via the pci_iomap_wc()
and pci_iomap_wc_range() functions.
This is achieved by using the write back address for a specific bar
as provided in clp_store_query_pci_fn()

These functions are however not widely used and instead drivers often
rely on ioremap_wc() and ioremap_prot(), which on other platforms enable
write combining using a PTE flag set through the pgrprot value.

While we do not have a write combining flag in the low order flag bits
of the PTE like x86_64 does, with MIO support, there is a write back bit
in the physical address (bit 1 on z15) and thus also the PTE.
Which bit is used to toggle write back and whether it is available at
all, is however not fixed in the architecture. Instead we get this
information from the CLP Store Logical Processor Characteristics for PCI
command. When the write back bit is not provided we fall back to the
existing behavior.
Signed-off-by: NNiklas Schnelle <schnelle@linux.ibm.com>
Reviewed-by: NPierre Morel <pmorel@linux.ibm.com>
Reviewed-by: NGerald Schaefer <gerald.schaefer@linux.ibm.com>
Signed-off-by: NVasily Gorbik <gor@linux.ibm.com>

commit f606b3ef ("s390/pci: adapt events for zbus") removed the
zpci_disable_device() call for a zPCI event with PEC 0x0304 because
the device is already deconfigured by the platform.
This however skips the Linux side of the disable in particular it leads
to leaking the DMA tables and bitmaps because zpci_dma_exit_device() is
never called on the device.

If the device transitions to the Reserved state we call zpci_zdev_put()
but zpci_release_device() will not call zpci_disable_device() because
the state of the zPCI function is already ZPCI_FN_STATE_STANDBY.

If the device is put into the Standby state, zpci_disable_device() is
not called and the device is assumed to have been put in Standby through
platform action.
At this point the device may be removed by a subsequent event with PEC
0x0308 or 0x0306 which calls zpci_zdev_put() with the same problem
as above or the device may be configured again in which case
zpci_disable_device() is also not called.

Fix this by calling zpci_disable_device() explicitly for PEC 0x0304 as
before. To make it more clear that zpci_disable_device() may be called,
even if the lower level device has already been disabled by the
platform, add a comment to zpci_disable_device().

Cc: <stable@vger.kernel.org> # 5.8
Fixes: f606b3ef ("s390/pci: adapt events for zbus")
Signed-off-by: NNiklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: NVasily Gorbik <gor@linux.ibm.com>

Currently there are four places in which a PCI function is scanned
and made available to drivers:
 1. In pci_scan_root_bus() as part of the initial zbus
    creation.
 2. In zpci_bus_add_devices() when registering
    a device in configured state on a zbus that has already been
    scanned.
 3. When a function is already known to zPCI (in reserved/standby state)
    and configuration is triggered through firmware by PEC 0x301.
 4. When a device is already known to zPCI (in standby/reserved state)
    and configuration is triggered from within Linux using
    enable_slot().

The PF/VF linking step and setting of pdev->is_virtfn introduced with
commit e5794cf1 ("s390/pci: create links between PFs and VFs") was
only triggered for the second case, which is where VFs created through
sriov_numvfs usually land. However unlike some other platforms but like
POWER VFs can be individually enabled/disabled through
/sys/bus/pci/slots.

Fix this by doing VF setup as part of pcibios_bus_add_device() which is
called in all of the above cases.

Finally to remove the PF/VF links call the common code
pci_iov_remove_virtfn() function to remove linked VFs.
This takes care of the necessary sysfs cleanup.

Fixes: e5794cf1 ("s390/pci: create links between PFs and VFs")
Cc: <stable@vger.kernel.org> # 5.8: 2f0230b2: s390/pci: re-introduce zpci_remove_device()
Cc: <stable@vger.kernel.org> # 5.8
Acked-by: NPierre Morel <pmorel@linux.ibm.com>
Signed-off-by: NNiklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: NHeiko Carstens <hca@linux.ibm.com>

For fixing the PF to VF link removal we need to perform some action on
every removal of a zdev from the common PCI subsystem.
So in preparation re-introduce zpci_remove_device() and use that instead
of directly calling the common code functions. This  was actually still
declared from earlier code but no longer implemented.
Reviewed-by: NPierre Morel <pmorel@linux.ibm.com>
Signed-off-by: NNiklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: NHeiko Carstens <hca@linux.ibm.com>

Let's use the same signature and parameter names as in the generic
ioremap() definition making the physical address' type explicit.

Add a check against address wrap around as in the generic
lib/ioremap.c:ioremap_prot() code.

Finally use free_vm_area() instead of vunmap() as in the generic code.
Besides being clearer free_vm_area() can also skip a few additional
checks compared with vunmap().
Signed-off-by: NNiklas Schnelle <schnelle@linux.ibm.com>
Reviewed-by: NGerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: NVasily Gorbik <gor@linux.ibm.com>

We allow multiple functions on a single bus.
We suppress the ZPCI_DEVFN definition and replace its
occurences with zpci->devfn.

We verify the number of device during the registration.

There can never be more domains in use than existing
devices, so we do not need to verify the count of domain
after having verified the count of devices.
Signed-off-by: NPierre Morel <pmorel@linux.ibm.com>
Reviewed-by: NNiklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: NVasily Gorbik <gor@linux.ibm.com>

The zPCI bus is in charge to handle common zPCI resources for
zPCI devices.

Creating the zPCI bus, the PCI bus, the zPCI devices and the
PCI devices and hotplug slots
done in a specific order:
- PCI hotplug slot creation needs a PCI bus
- PCI bus needs a PCI domain
  which is reported by the pci_domain_nr() when setting up the
  host bridge
- PCI domain is set from the zPCI with devfn 0
  this is necessary to have a reproducible enumeration

Therefore we can not create devices or hotplug slots for any PCI
device associated with a zPCI device before having discovered
the function zero of the bus.

The discovery and initialization of devices can be done at several
points in the code:
- On Events, serialized in a thread context
- On initialization, in the kernel init thread context
- When powering on the hotplug slot, in a user thread context

The removal of devices and their parent bus may also be done on
events or for devices when powering down the slot.

To guarantee the existence of the bus and devices until they are
no more needed we use kref in zPCI bus and introduce a reference
count in the zPCI devices.

In this patch the zPCI bus still only accept a device with
a devfn 0.
Signed-off-by: NPierre Morel <pmorel@linux.ibm.com>
Reviewed-by: NNiklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: NVasily Gorbik <gor@linux.ibm.com>

Using PCI multifunctions in S390 is a new feature we may want
to ignore to continue provide the same topology as in the past
to userland even if the configuration supports exposing the
topology of a multi-Function device.

A new boolean parameters allows to overwrite the kernel
pci configuration:

- pci=norid when on, disallow the use a new firmware field,
  RID, which provides the PCI <bus>:<device>.<function> part
  of the PCI address.

To be used in the following patches and satisfy the checkpatch.pl
the variable is exposed in pci.h
Signed-off-by: NPierre Morel <pmorel@linux.ibm.com>
Reviewed-by: NNiklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: NVasily Gorbik <gor@linux.ibm.com>

When UID checking is enabled a UID value of 0 is invalid and can not be
set by the user. On z/VM it is however used to indicate an unset UID.
Until now, this lead to the behavior that one PCI function could be
attached with UID 0 after which z/VM would prohibit further attachment.

Now if the user then turns off UID checking in z/VM the user could
seemingly attach additional PCI functions that would however not show up
in Linux as that would not be informed of the change in UID checking
mode. This is unexpected and confusing and lead to bug reports against
Linux.

Instead now, if we encounter an unset UID value of 0 treat it as
indicating that UID checking was turned off, switch to automatic domain
allocation, and warn the user of the possible misconfiguration.
Signed-off-by: NNiklas Schnelle <schnelle@linux.ibm.com>
Reviewed-by: NPeter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: NVasily Gorbik <gor@linux.ibm.com>

Until now zpci_alloc_domain() only prevented more than
CONFIG_PCI_NR_FUNCTIONS from being added when using automatic domain
allocation. When explicit UIDs were defined UIDs above
CONFIG_PCI_NR_FUNCTIONS were not counted at all.
When more PCI functions are added this could lead to various errors
including under sized IRQ vectors and similar issues.

Fix this by explicitly tracking the number of allocated domains.
Signed-off-by: NNiklas Schnelle <schnelle@linux.ibm.com>
Reviewed-by: NPierre Morel <pmorel@linux.ibm.com>
Signed-off-by: NVasily Gorbik <gor@linux.ibm.com>

Hibernation is known to be broken for many years on s390. Given that
there aren't any real use cases, remove the code instead of spending
time to fix and maintain it.

Without hibernate support it doesn't make too much sense to keep power
management support; therefore remove it completely.
Acked-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Acked-by: NPeter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NVasily Gorbik <gor@linux.ibm.com>

In the initial MIO support introduced in

commit 71ba41c9 ("s390/pci: provide support for MIO instructions")

zpci_map_resource() and zpci_setup_resources() default to using the
mio_wb address as the resource's start address. This means users of the
mapping, which includes most drivers, will get write combining on PCI
Stores. This may lead to problems when drivers expect write through
behavior when not using an explicit ioremap_wc().

Cc: stable@vger.kernel.org
Fixes: 71ba41c9 ("s390/pci: provide support for MIO instructions")
Signed-off-by: NNiklas Schnelle <schnelle@linux.ibm.com>
Reviewed-by: NPierre Morel <pmorel@linux.ibm.com>
Signed-off-by: NVasily Gorbik <gor@linux.ibm.com>

When we try to recover a PCI function using

    echo 1 > /sys/bus/pci/devices/<id>/recover

or manually with

    echo 1 > /sys/bus/pci/devices/<id>/remove
    echo 0 > /sys/bus/pci/slots/<slot>/power
    echo 1 > /sys/bus/pci/slots/<slot>/power

clp_disable_fn() / clp_enable_fn() call clp_set_pci_fn() to first
disable and then reenable the function.

When the function is already in the requested state we may be left with
an invalid function handle.

To get a new valid handle we do a clp_list_pci() call. For this we need
both the function ID and function handle in clp_set_pci_fn() so pass the
zdev and get both.

To simplify things also pull setting the refreshed function handle into
clp_set_pci_fn()
Signed-off-by: NNiklas Schnelle <schnelle@linux.ibm.com>
Reviewed-by: NPeter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: NVasily Gorbik <gor@linux.ibm.com>

The config option CONFIG_PCI_NR_FUNCTIONS sets a limit on the number of
PCI functions we can support. Previously on reaching this limit there
was no indication why newly attached devices are not recognized by Linux
which could be quite confusing. Thus this patch adds a pr_err() for this
case.
Reviewed-by: NPeter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: NNiklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: NVasily Gorbik <gor@linux.ibm.com>

When UID checking was turned off during runtime in the underlying
hypervisor, a PCI device may be attached with the same UID. This is
already detected but happens silently. Add an error message so it can
more easily be understood why a device was not added.
Reviewed-by: NPeter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: NNiklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: NVasily Gorbik <gor@linux.ibm.com>

Code that iterates over all standard PCI BARs typically uses
PCI_STD_RESOURCE_END.  However, that requires the unusual test
"i <= PCI_STD_RESOURCE_END" rather than something the typical
"i < PCI_STD_NUM_BARS".

Add a definition for PCI_STD_NUM_BARS and change loops to use the more
idiomatic C style to help avoid fencepost errors.

Link: https://lore.kernel.org/r/20190927234026.23342-1-efremov@linux.com
Link: https://lore.kernel.org/r/20190927234308.23935-1-efremov@linux.com
Link: https://lore.kernel.org/r/20190916204158.6889-3-efremov@linux.comSigned-off-by: NDenis Efremov <efremov@linux.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Acked-by: Sebastian Ott <sebott@linux.ibm.com>			# arch/s390/
Acked-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>	# video/fbdev/
Acked-by: Gustavo Pimentel <gustavo.pimentel@synopsys.com>	# pci/controller/dwc/
Acked-by: Jack Wang <jinpu.wang@cloud.ionos.com>		# scsi/pm8001/
Acked-by: Martin K. Petersen <martin.petersen@oracle.com>	# scsi/pm8001/
Acked-by: Ulf Hansson <ulf.hansson@linaro.org>			# memstick/

This patch alters the for loop iteration scheme in zpci_map_resources
to make it more usual. Thus, the patch generalizes the style for
PCI_IOV_RESOURCES iteration and improves readability.

Link: http://lkml.kernel.org/r/20190806160137.29275-1-efremov@linux.comSigned-off-by: NDenis Efremov <efremov@linux.com>
Signed-off-by: NSebastian Ott <sebott@linux.ibm.com>
Signed-off-by: NVasily Gorbik <gor@linux.ibm.com>

Move enablement of mio addressing control from detect_machine_facilities
to pci_base_init. detect_machine_facilities runs so early that the
static branches have not been toggled yet, thus mio addressing control
was always off. In pci_base_init we have to use the SMP aware
ctl_set_bit though.

Fixes: 833b441e ("s390: enable processes for mio instructions")
Signed-off-by: NSebastian Ott <sebott@linux.ibm.com>
Signed-off-by: NVasily Gorbik <gor@linux.ibm.com>

Unfortunately we have to handle a class of devices that don't support the
new MIO instructions. Adjust resource assignment and mapping accordingly.
Signed-off-by: NSebastian Ott <sebott@linux.ibm.com>
Signed-off-by: NVasily Gorbik <gor@linux.ibm.com>

Adjust bus resources depending on the usage of MIO instructions.

Fixes: 71ba41c9 ("s390/pci: provide support for MIO instructions")
Signed-off-by: NSebastian Ott <sebott@linux.ibm.com>
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>

Allow users to disable usage of MIO instructions by specifying pci=nomio
at the kernel command line.
Signed-off-by: NSebastian Ott <sebott@linux.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Provide support for PCI I/O instructions that work on mapped IO addresses.
Signed-off-by: NSebastian Ott <sebott@linux.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

This is a preparation patch for usage of new pci instructions.
No functional change.
Signed-off-by: NSebastian Ott <sebott@linux.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>