linux-toradex.git/drivers/pci/host/pci-versatile.c, branch v4.15

PCI: versatile: Add local struct device pointers

2017-07-02T23:46:43+00:00

Use a local "struct device *dev" for brevity and consistency with other
drivers.  No functional change intended.

Signed-off-by: Bjorn Helgaas

PCI: versatile: Drop pci_fixup_irqs()

2017-07-02T21:51:19+00:00

Since, through struct pci_host_bridge.map/swizzle_irq hooks, IRQs are now
allocated in the pci_assign_irq() callback automatically, PCI host bridge
drivers can stop relying on pci_fixup_irqs() for IRQ allocation.

Drop pci_fixup_irqs() usage from PCI versatile host bridge driver.

Signed-off-by: Lorenzo Pieralisi 
[bhelgaas: folded in typo fix from Arnd Bergmann :
http://lkml.kernel.org/r/20170621215323.3921382-4-arnd@arndb.de]
Signed-off-by: Bjorn Helgaas 
Cc: Rob Herring

PCI: versatile: Convert PCI scan API to pci_scan_root_bus_bridge()

2017-07-02T21:14:24+00:00

The introduction of pci_scan_root_bus_bridge() provides a PCI core API to
scan a PCI root bus backed by an already initialized struct pci_host_bridge
object, which simplifies the bus scan interface and makes the PCI scan root
bus interface easier to generalize as members are added to the struct
pci_host_bridge.

Convert PCI versatile host code to pci_scan_root_bus_bridge() to improve
the PCI root bus scanning interface.

Signed-off-by: Lorenzo Pieralisi 
[bhelgaas: folded in fix from Arnd Bergmann :
http://lkml.kernel.org/r/20170621215323.3921382-3-arnd@arndb.de]
Signed-off-by: Bjorn Helgaas 
Cc: Rob Herring

PCI: Don't allow unbinding host controllers that aren't prepared

2017-04-28T15:38:00+00:00

Many PCI host controller drivers aren't prepared to have their devices
unbound from them forcefully (e.g., through /sys/...//unbind), as
they don't provide any driver .remove callback, where they'd detach the
root bus, release resources, etc. Keeping the driver built in (i.e., not a
loadable module) is not enough; and providing no .remove callback just
means we don't do any teardown.

To rule out the possibility of unbinding a device via sysfs, we need to set
the ".suppress_bind_attrs" field.

I found the suspect drivers via the following search:

  git grep -l platform_driver $(git grep -L -e '\.remove' -e suppress_bind_attrs drivers/pci/)

Then I inspected them to ensure that
(a) they set up a PCI bus in their probe() and
(b) they don't have a remove() callback for undoing the setup

Suggested-by: Bjorn Helgaas 
Signed-off-by: Brian Norris 
Signed-off-by: Bjorn Helgaas

PCI: versatile: Update PCI config space remap function

2017-04-24T18:53:18+00:00

PCI configuration space should be mapped with a memory region type that
generates on the CPU host bus non-posted write transations. Update the
driver to use the devm_ioremap_nopost* interface to make sure the correct
memory mappings for PCI configuration space are used.

Signed-off-by: Lorenzo Pieralisi 
Signed-off-by: Bjorn Helgaas 
Cc: Rob Herring

PCI: versatile: Configure PCIe MPS settings

2017-02-08T21:42:26+00:00

Make sure PCIe MPS settings are valid when we enumerate a new hierarchy.

Based-on-patch-by: Jon Mason 
Signed-off-by: Bjorn Helgaas

PCI: versatile: Fix pci_remap_iospace() failure path

2016-09-06T17:41:15+00:00

On ARM/ARM64 architectures, PCI IO ports are emulated through memory mapped
IO, by reserving a chunk of virtual address space starting at PCI_IOBASE
and by mapping the PCI host bridges memory address space driving PCI IO
cycles to it.

PCI host bridge drivers that enable downstream PCI IO cycles map the host
bridge memory address responding to PCI IO cycles to the fixed virtual
address space through the pci_remap_iospace() API.

This means that if the pci_remap_iospace() function fails, the
corresponding host bridge PCI IO resource must be considered invalid, in
that there is no way for the kernel to actually drive PCI IO transactions
if the memory addresses responding to PCI IO cycles cannot be mapped into
the CPU virtual address space.

The PCI versatile host bridge driver does not remove the PCI IO resource
from the host bridge resource windows if the pci_remap_iospace() call
fails; this is an actual bug in that the PCI host bridge would consider the
PCI IO resource valid (and possibly assign it to downstream devices) even
if the kernel was not able to map the PCI host bridge memory address
driving IO cycle to the CPU virtual address space (ie pci_remap_iospace()
failures).

Fix the PCI host bridge driver pci_remap_iospace() failure path, by
destroying the PCI host bridge PCI IO resources retrieved through firmware
when the pci_remap_iospace() function call fails, therefore preventing the
kernel from adding the respective PCI IO resource to the list of PCI host
bridge valid resources, fixing the issue.

Fixes: b7e78170efd4 ("PCI: versatile: Add DT-based ARM Versatile PB PCIe host driver")
Signed-off-by: Lorenzo Pieralisi 
Signed-off-by: Bjorn Helgaas 
CC: Rob Herring

PCI: versatile: Simplify host bridge window iteration

2016-06-25T12:44:24+00:00

The switch is the only statement in the resource_list_for_each_entry()
loop, so remove unnecessary "continue" statements in the switch.  Simplify
checking for the required non-prefetchable memory aperture.

No functional change intended.

Signed-off-by: Bjorn Helgaas

PCI: versatile: Request host bridge window resources with core function

2016-06-25T12:44:24+00:00

Use devm_request_pci_bus_resources() to request host bridge window
resources instead of doing it by hand in the driver.

No functional change intended.

Signed-off-by: Bjorn Helgaas

PCI: generic,versatile: Remove unused pci_sys_data structures

2015-11-25T18:08:04+00:00

Commit b3a72384fe29 ("ARM/PCI: Replace pci_sys_data->align_resource with
global function pointer") removed the struct pci_sys_data dependency from
the ARM pcibios functions that are part of the common ARM PCI arch
back-end, e.g., pcibios_align_resource(), so that struct pci_sys_data has
now become data that is only used internally by the ARM bios32 layer, i.e.,
pci_common_init_dev(), and by host controllers drivers callbacks, e.g.,
pci_sys_data.setup, that rely on the ARM bios32 API to probe.

PCI host controller drivers that do not rely on ARM bios32 calls to probe
do not need to have the pci_bus.sysdata pointer field pointing at a struct
pci_sys_data anymore, therefore it can be removed from the respective
drivers data structures.

Remove the pci_sys_data structures from the host controller drivers that do
not rely on ARM bios32 interface to scan the PCI bus, completing the
pci_sys_data clean-up and removing the related dependency on arch/arm
specific data.

Signed-off-by: Lorenzo Pieralisi 
Signed-off-by: Bjorn Helgaas 
Acked-by: Arnd Bergmann 
CC: Will Deacon 
CC: Rob Herring