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+UniPhier System Bus
+
+The UniPhier System Bus is an external bus that connects on-board devices to
+the UniPhier SoC. It is a simple (semi-)parallel bus with address, data, and
+some control signals. It supports up to 8 banks (chip selects).
+
+Before any access to the bus, the bus controller must be configured; the bus
+controller registers provide the control for the translation from the offset
+within each bank to the CPU-viewed address. The needed setup includes the base
+address, the size of each bank. Optionally, some timing parameters can be
+optimized for faster bus access.
+
+Required properties:
+- compatible: should be "socionext,uniphier-system-bus".
+- reg: offset and length of the register set for the bus controller device.
+- #address-cells: should be 2. The first cell is the bank number (chip select).
+ The second cell is the address offset within the bank.
+- #size-cells: should be 1.
+- ranges: should provide a proper address translation from the System Bus to
+ the parent bus.
+
+Note:
+The address region(s) that can be assigned for the System Bus is implementation
+defined. Some SoCs can use 0x00000000-0x0fffffff and 0x40000000-0x4fffffff,
+while other SoCs can only use 0x40000000-0x4fffffff. There might be additional
+limitations depending on SoCs and the boot mode. The address translation is
+arbitrary as long as the banks are assigned in the supported address space with
+the required alignment and they do not overlap one another.
+For example, it is possible to map:
+ bank 0 to 0x42000000-0x43ffffff, bank 5 to 0x46000000-0x46ffffff
+It is also possible to map:
+ bank 0 to 0x48000000-0x49ffffff, bank 5 to 0x44000000-0x44ffffff
+There is no reason to stick to a particular translation mapping, but the
+"ranges" property should provide a "reasonable" default that is known to work.
+The software should initialize the bus controller according to it.
+
+Example:
+
+ system-bus {
+ compatible = "socionext,uniphier-system-bus";
+ reg = <0x58c00000 0x400>;
+ #address-cells = <2>;
+ #size-cells = <1>;
+ ranges = <1 0x00000000 0x42000000 0x02000000
+ 5 0x00000000 0x46000000 0x01000000>;
+
+ ethernet@1,01f00000 {
+ compatible = "smsc,lan9115";
+ reg = <1 0x01f00000 0x1000>;
+ interrupts = <0 48 4>
+ phy-mode = "mii";
+ };
+
+ uart@5,00200000 {
+ compatible = "ns16550a";
+ reg = <5 0x00200000 0x20>;
+ interrupts = <0 49 4>
+ clock-frequency = <12288000>;
+ };
+ };
+
+In this example,
+ - the Ethernet device is connected at the offset 0x01f00000 of CS1 and
+ mapped to 0x43f00000 of the parent bus.
+ - the UART device is connected at the offset 0x00200000 of CS5 and
+ mapped to 0x46200000 of the parent bus.