[RFC DT style 4/4] docs/mtd/nand/sh_flctl: Initial device tree binding specification

[Bastian Hecht <hechtb@googlemail.com>]

Add documentation for setting up the flctl flash controller via device
tree description.
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 .../devicetree/bindings/mtd/rmobile-flctl.txt      |   58 ++++++++++++++++++++
 1 files changed, 58 insertions(+), 0 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/mtd/rmobile-flctl.txt

diff --git a/Documentation/devicetree/bindings/mtd/rmobile-flctl.txt b/Documentation/devicetree/bindings/mtd/rmobile-flctl.txt
new file mode 100644
index 0000000..ee0011b
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+++ b/Documentation/devicetree/bindings/mtd/rmobile-flctl.txt
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+Renesas RMobile Flash controller FLCTL.
+
+Controller properties:
+- compatible:	"rmobile,flctl".
+- reg:		I/O map base address.
+- ext-bus-con:	"SHBUSSEL - External Bus Connection". Set this flag when the
+		I/O is multiplexed with the external bus through BSC.
+- release-bus:	"HOLDEN - Bus occupancy enable". Set this flag if the bus shall
+		be released when the FIFO becomes empty or full.
+- clk-scheme:	The bit fields differ between different hardware releases.
+		Please consult the datasheet and select a proper u32 that
+		is OR'ed to FLCMNCR.
+
+For each NAND chip connected to the FLCTL add a subnode compliant to mtd/nand
+bindings.
+
+- nand-ecc-mode: See nand.txt. Hardware and software ECC modes are supported.
+- nand-bus-width: See nand.txt. 16 and 8 bit widths are supported.
+- flctl-snand:	"SNAND - Large capacity NAND Flash Memory Select". Set this for
+		2k page size NAND chips or for AG-AND-type chips with a capacity
+		of 1Gb or more.
+
+These options may follow partition definitions, see partition.txt.
+
+Examples:
+
+flctl@e6000000 {
+	compatible = "rmobile,flctl";
+	reg = <0xe6000000 0x100>;
+
+	ext-bus-con;
+	use-holden;
+	clk-scheme = <0x20200>; /* Low 12, high 4 cycles */
+
+	nand@0 {
+		#address-cells = <1>;
+		#size-cells = <1>;
+
+		nand-ecc-mode = "hw";
+		nand-bus-width = <16>;
+		nand-large-page;
+
+		system@0 {
+			label = "system";
+			reg = <0x0 0x8000000>;
+		};
+
+		userdata@8000000 {
+			label = "userdata";
+			reg = <0x8000000 0x10000000>;
+		};
+
+		cache@18000000 {
+			label = "cache";
+			reg = <0x18000000 0x8000000>;
+		};
+	};
+};
-- 
1.7.5.4