Add a parent device field to struct pci_config_window.  The parent is not
saved now, but will be useful to save it in some cases.  For ACPI on ARM64,
it can be used to setup ACPI companion and domain.

Since the parent dev is in struct pci_config_window now, we need not pass
it to the init function as a separate argument.
Signed-off-by: NJayachandran C <jchandra@broadcom.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Acked-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>

This header will be used from arch/arm64 for ACPI PCI implementation so it
needs to be moved out of drivers/pci.

Update users of the header file to use the new name.  No functional
changes.
Signed-off-by: NJayachandran C <jchandra@broadcom.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Acked-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>

Use functions provided by drivers/pci/ecam.h for mapping the config space
in drivers/pci/host/pci-host-common.c, and update its users to use 'struct
pci_config_window' and 'struct pci_ecam_ops'.

The changes are mostly to use 'struct pci_config_window' in place of
'struct gen_pci'.  Some of the fields of gen_pci were only used temporarily
and can be eliminated by using local variables or function arguments, these
are not carried over to struct pci_config_window.

pci-thunder-ecam.c and pci-thunder-pem.c are the only users of the
pci_host_common_probe function and the gen_pci structure; these have been
updated to use the new API as well.

The patch does not introduce any functional changes other than a very minor
one: with the new code, on 64-bit platforms, we do just a single ioremap
for the whole config space.
Signed-off-by: NJayachandran C <jchandra@broadcom.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>

The 32-bit addressing modes in the I/O and Prefetchable Memory registers
are required to be read-only.  Since the underlying access method allows
them to be set, emulate their read-only nature and always set them.
Signed-off-by: NDavid Daney <david.daney@cavium.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>

The root complexes used to access off-chip PCIe devices (called PEM units
in the hardware manuals) on some Cavium ThunderX processors require quirky
access methods for the config space of the PCIe bridge.

Add a driver to provide these config space accessor functions.  Use the
pci-host-common code to configure the PCI machinery.
Signed-off-by: NDavid Daney <david.daney@cavium.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Acked-by: NRob Herring <robh@kernel.org>
Acked-by: NArnd Bergmann <arnd@arndb.de>