of/pci: Add pci_register_io_range() and pci_pio_to_address()
Some architectures do not have a simple view of the PCI I/O space and
instead use a range of CPU addresses that map to bus addresses. For some
architectures these ranges will be expressed by OF bindings in a device
tree file.
This patch introduces a pci_register_io_range() helper function with a
generic implementation that can be used by such architectures to keep track
of the I/O ranges described by the PCI bindings. If the PCI_IOBASE macro
is not defined, that signals lack of support for PCI and we return an
error.
In order to retrieve the CPU address associated with an I/O port, a new
helper function pci_pio_to_address() is introduced. This will search in
the list of ranges registered with pci_register_io_range() and return the
CPU address that corresponds to the given port.
[arnd: add dummy !CONFIG_OF pci_pio_to_address() to fix build errors]
Signed-off-by: Liviu Dudau <Liviu.Dudau@arm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Rob Herring <robh@kernel.org>
CC: Grant Likely <grant.likely@linaro.org>
diff --git a/include/linux/of_address.h b/include/linux/of_address.h
index fb7b722..497a043 100644
--- a/include/linux/of_address.h
+++ b/include/linux/of_address.h
@@ -55,7 +55,9 @@
extern const __be32 *of_get_address(struct device_node *dev, int index,
u64 *size, unsigned int *flags);
+extern int pci_register_io_range(phys_addr_t addr, resource_size_t size);
extern unsigned long pci_address_to_pio(phys_addr_t addr);
+extern phys_addr_t pci_pio_to_address(unsigned long pio);
extern int of_pci_range_parser_init(struct of_pci_range_parser *parser,
struct device_node *node);
@@ -80,6 +82,11 @@
return NULL;
}
+static inline phys_addr_t pci_pio_to_address(unsigned long pio)
+{
+ return 0;
+}
+
static inline int of_pci_range_parser_init(struct of_pci_range_parser *parser,
struct device_node *node)
{