On Mon, Feb 19, 2018 at 7:48 PM, John Garry [off-list ref] wrote:

From: Zhichang Yuan <redacted>

There are some special ISA/LPC devices that work on a specific I/O range
where it is not correct to specify a 'ranges' property in DTS parent node
as cpu addresses translated from DTS node are only for memory space on
some architectures, such as Arm64. Without the parent 'ranges' property,
current of_translate_address() return an error.
Here we add special handlings for this case.
During the OF address translation, some checkings will be perfromed to
identify whether the device node is registered as indirect-IO. If yes,
the I/O translation will be done in a different way from that one of PCI
MMIO. In this way, the I/O 'reg' property of the special ISA/LPC devices
will be parsed correctly.

+               /*
+                * For indirectIO device which has no ranges property, get
+                * the address from reg directly.
+                */
+               iorange = find_io_range_by_fwnode(&dev->fwnode);
+               if (iorange && (iorange->flags != PIO_CPU_MMIO)) {
+                       result = of_read_number(addr + 1, na - 1);
+                       pr_debug("indirectIO matched(%s) 0x%llx\n",
+                                       of_node_full_name(dev), result);

%pOF ?

+                       *host = of_node_get(dev);
+                       break;
+               }

+static u64 of_translate_ioport(struct device_node *dev, const __be32 *in_addr,
+                       u64 size)
+{
+       u64 taddr;
+       unsigned long port;
+       struct device_node *host;
+
+       taddr = __of_translate_address(dev, in_addr, "ranges", &host);
+       if (host) {
+               /* host specific port access */
+               port = logic_pio_trans_hwaddr(&host->fwnode, taddr, size);
+               of_node_put(host);
+       } else {
+               /* memory mapped I/O range */
+               port = pci_address_to_pio(taddr);
+       }
+
+       if (port == (unsigned long)-1)
+               return OF_BAD_ADDR;

~0UL ?

Ah, okay, old code on plate.

+
+       return port;
+}

-- 
With Best Regards,
Andy Shevchenko