+/* This provides legacy IO read access on a bus */
+int pci_legacy_read(struct pci_bus *bus, loff_t port, u32 *val, size_t size)
+{
+ unsigned long offset;
+ struct pci_controller *hose = pci_bus_to_host(bus);
+ struct resource *rp = &hose->io_resource;
+ void __iomem *addr;
+
+ /* Check if port can be supported by that bus. We only check
+ * the ranges of the PHB though, not the bus itself as the rules
+ * for forwarding legacy cycles down bridges are not our problem
+ * here. So if the host bridge supports it, we do it.
+ */
+ offset = (unsigned long)hose->io_base_virt - _IO_BASE;
+ offset += port;
+
+ if (!(rp->flags & IORESOURCE_IO))
+ return -ENXIO;
+ if (offset < rp->start || (offset + size) > rp->end)
+ return -ENXIO;
+ addr = hose->io_base_virt + port;
+
+ switch(size) {
+ case 1:
+ *((u8 *)val) = in_8(addr);
+ return 1;
+ case 2:
+ if (port & 1)
+ return -EINVAL;
+ *((u16 *)val) = in_le16(addr);
+ return 2;
+ case 4:
+ if (port & 3)
+ return -EINVAL;
+ *((u32 *)val) = in_le32(addr);
+ return 4;
+ }
+ return -EINVAL;
+}
+
+/* This provides legacy IO write access on a bus */
+int pci_legacy_write(struct pci_bus *bus, loff_t port, u32 val, size_t size)
+{
+ unsigned long offset;
+ struct pci_controller *hose = pci_bus_to_host(bus);
+ struct resource *rp = &hose->io_resource;
+ void __iomem *addr;
+
+ /* Check if port can be supported by that bus. We only check
+ * the ranges of the PHB though, not the bus itself as the rules
+ * for forwarding legacy cycles down bridges are not our problem
+ * here. So if the host bridge supports it, we do it.
+ */
+ offset = (unsigned long)hose->io_base_virt - _IO_BASE;
+ offset += port;
+
+ if (!(rp->flags & IORESOURCE_IO))
+ return -ENXIO;
+ if (offset < rp->start || (offset + size) > rp->end)
+ return -ENXIO;
+ addr = hose->io_base_virt + port;
+
+ /* WARNING: The generic code is idiotic. It gets passed a pointer
+ * to what can be a 1, 2 or 4 byte quantity and always reads that
+ * as a u32, which means that we have to correct the location of
+ * the data read within those 32 bits for size 1 and 2
+ */
+ switch(size) {
+ case 1:
+ out_8(addr, val >> 24);
+ return 1;
+ case 2:
+ if (port & 1)
+ return -EINVAL;
+ out_le16(addr, val >> 16);
+ return 2;
+ case 4:
+ if (port & 3)
+ return -EINVAL;
+ out_le32(addr, val);
+ return 4;
+ }
+ return -EINVAL;
+}
+
+/* This provides legacy IO or memory mmap access on a bus */
+int pci_mmap_legacy_page_range(struct pci_bus *bus,
+ struct vm_area_struct *vma,
+ enum pci_mmap_state mmap_state)
+{
+ struct pci_controller *hose = pci_bus_to_host(bus);
+ resource_size_t offset =
+ ((resource_size_t)vma->vm_pgoff) << PAGE_SHIFT;
+ resource_size_t size = vma->vm_end - vma->vm_start;
+ struct resource *rp;
+
+ pr_debug("pci_mmap_legacy_page_range(%04x:%02x, %s @%llx..%llx)\n",
+ pci_domain_nr(bus), bus->number,
+ mmap_state == pci_mmap_mem ? "MEM" : "IO",
+ (unsigned long long)offset,
+ (unsigned long long)(offset + size - 1));
+
+ if (mmap_state == pci_mmap_mem) {
+ if ((offset + size) > hose->isa_mem_size)
+ return -ENXIO;
+ offset += hose->isa_mem_phys;
+ } else {
+ unsigned long io_offset = (unsigned long)hose->io_base_virt - _IO_BASE;
+ unsigned long roffset = offset + io_offset;
+ rp = &hose->io_resource;
+ if (!(rp->flags & IORESOURCE_IO))
+ return -ENXIO;
+ if (roffset < rp->start || (roffset + size) > rp->end)
+ return -ENXIO;
+ offset += hose->io_base_phys;
+ }
+ pr_debug(" -> mapping phys %llx\n", (unsigned long long)offset);
+
+ vma->vm_pgoff = offset >> PAGE_SHIFT;
+ vma->vm_page_prot = __pgprot(pgprot_val(vma->vm_page_prot)
+ | _PAGE_NO_CACHE | _PAGE_GUARDED);
+ return remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff,
+ vma->vm_end - vma->vm_start,
+ vma->vm_page_prot);
+}
+