PCI/alpha: pci sysfs resources

This closes http://bugzilla.kernel.org/show_bug.cgi?id=10893
which is a showstopper for X development on alpha.

The generic HAVE_PCI_MMAP code (drivers/pci-sysfs.c) is not
very useful since we have to deal with three different types
of MMIO address spaces: sparse and dense mappings for old
ev4/ev5 machines and "normal" 1:1 MMIO space (bwx) for ev56 and
later.
Also "write combine" mappings are meaningless on alpha - roughly
speaking, alpha does write combining, IO reordering and other
optimizations by default, unless user splits IO accesses
with memory barriers.

I think the cleanest way to deal with resource files on alpha
is to convert the default no-op pci_create_resource_files() and
pci_remove_resource_files() for !HAVE_PCI_MMAP case into __weak
functions and override them with alpha specific ones.

Another alpha hook is needed for "legacy_" resource files
to handle sparse addressing (pci_adjust_legacy_attr).

With the "standard" resourceN files on ev56/ev6 libpciaccess
works "out of the box". Handling of resourceN_sparse/resourceN_dense
files on older machines obviously requires some userland work.

Sparse/dense stuff has been tested on sx164 (pca56/pyxis, normally
uses bwx IO) with the kernel hacked into "cia compatible" mode.

Signed-off-by: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

1 files changed, 14 insertions, 0 deletions

diff --git a/arch/alpha/include/asm/pci.h b/arch/alpha/include/asm/pci.h
index 2a14302c17a3..cb04eaa6ba33 100644
--- a/arch/alpha/include/asm/pci.h
+++ b/arch/alpha/include/asm/pci.h
@@ -273,4 +273,18 @@ struct pci_dev *alpha_gendev_to_pci(struct device *dev);
 
 extern struct pci_dev *isa_bridge;
 
+extern int pci_legacy_read(struct pci_bus *bus, loff_t port, u32 *val,
+                           size_t count);
+extern int pci_legacy_write(struct pci_bus *bus, loff_t port, u32 val,
+                            size_t count);
+extern int pci_mmap_legacy_page_range(struct pci_bus *bus,
+                                      struct vm_area_struct *vma,
+                                      enum pci_mmap_state mmap_state);
+extern void pci_adjust_legacy_attr(struct pci_bus *bus,
+                                   enum pci_mmap_state mmap_type);
+#define HAVE_PCI_LEGACY 1
+
+extern int pci_create_resource_files(struct pci_dev *dev);
+extern void pci_remove_resource_files(struct pci_dev *dev);
+
 #endif /* __ALPHA_PCI_H */