PCI: Add generic config accessors
Many PCI controllers' configuration space accesses are memory-mapped and
vary only in address calculation and access checks. There are 2 main
access methods: a decoded address space such as ECAM or a single address
and data register similar to x86. This implementation can support both
cases as well as be used in cases that need additional pre- or post-access
handling.
Add a new pci_ops member, map_bus, which can do access checks and any
necessary setup. It returns the address to use for the configuration space
access. The access types supported are 32-bit only accesses or correct
byte, word, or dword sized accesses.
Tested-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Thierry Reding <treding@nvidia.com>
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 360a966..e7fd519 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -560,6 +560,7 @@
/* Low-level architecture-dependent routines */
struct pci_ops {
+ void __iomem *(*map_bus)(struct pci_bus *bus, unsigned int devfn, int where);
int (*read)(struct pci_bus *bus, unsigned int devfn, int where, int size, u32 *val);
int (*write)(struct pci_bus *bus, unsigned int devfn, int where, int size, u32 val);
};
@@ -857,6 +858,16 @@
int where, u16 val);
int pci_bus_write_config_dword(struct pci_bus *bus, unsigned int devfn,
int where, u32 val);
+
+int pci_generic_config_read(struct pci_bus *bus, unsigned int devfn,
+ int where, int size, u32 *val);
+int pci_generic_config_write(struct pci_bus *bus, unsigned int devfn,
+ int where, int size, u32 val);
+int pci_generic_config_read32(struct pci_bus *bus, unsigned int devfn,
+ int where, int size, u32 *val);
+int pci_generic_config_write32(struct pci_bus *bus, unsigned int devfn,
+ int where, int size, u32 val);
+
struct pci_ops *pci_bus_set_ops(struct pci_bus *bus, struct pci_ops *ops);
static inline int pci_read_config_byte(const struct pci_dev *dev, int where, u8 *val)