[PATCH v3 4/7] tegra: fdt: Add NAND controller binding and definitions

[Simon Glass <sjg@chromium.org>]

Add a NAND controller along with a bindings file for review.

Signed-off-by: Simon Glass <sjg@chromium.org>
---
Changes in v2:
- Update NAND binding to add "nvidia," prefix

Changes in v3:
- Add reg property for unit address (should be used for chip select)
- Change note in fdt binding about the need for a hardware-specific binding
- Fix up typos in fdt binding, and rename the file
- Update fdt binding to make everything Nvidia-specific

 arch/arm/dts/tegra20.dtsi                          |    6 ++
 .../nand/nvidia,tegra20-nand.txt                   |   68 ++++++++++++++++++++
 2 files changed, 74 insertions(+), 0 deletions(-)
 create mode 100644 doc/device-tree-bindings/nand/nvidia,tegra20-nand.txt

diff --git a/arch/arm/dts/tegra20.dtsi b/arch/arm/dts/tegra20.dtsi
index bc64f42..018a3c8 100644
--- a/arch/arm/dts/tegra20.dtsi
+++ b/arch/arm/dts/tegra20.dtsi
@@ -200,4 +200,10 @@
 		reg = <0x7000f400 0x200>;
 	};
 
+	nand: nand-controller@70008000 {
+		#address-cells = <1>;
+		#size-cells = <0>;
+		compatible = "nvidia,tegra20-nand";
+		reg = <0x70008000 0x100>;
+	};
 };
diff --git a/doc/device-tree-bindings/nand/nvidia,tegra20-nand.txt b/doc/device-tree-bindings/nand/nvidia,tegra20-nand.txt
new file mode 100644
index 0000000..2484556
--- /dev/null
+++ b/doc/device-tree-bindings/nand/nvidia,tegra20-nand.txt
@@ -0,0 +1,68 @@
+NAND Flash
+----------
+
+(there isn't yet a generic binding in Linux, so this describes what is in
+U-Boot. There should not be Linux-specific or U-Boot specific binding, just
+a binding that describes this hardware. But agreeing a binding in Linux in
+the absence of a driver may be beyond my powers.)
+
+The device node for a NAND flash device is as follows:
+
+Required properties :
+ - compatible : Should be "manufacturer,device", "nand-flash"
+ - nvidia,page-data-bytes : Number of bytes in the data area
+ - nvidia,page-spare-bytes : Number of bytes in spare area
+       spare area = skipped-spare-bytes + data-ecc-bytes + tag-bytes
+			+ tag-ecc-bytes
+ - nvidia,skipped-spare-bytes : Number of bytes to skip at start of spare area
+	(these are typically used for bad block maintenance)
+ - nvidia,data-ecc-bytes : Number of ECC bytes for data area
+ - nvidia,tag-bytes :Number of tag bytes in spare area
+ - nvidia,tag-ecc-bytes : Number ECC bytes to be generated for tag bytes
+
+This node should sit inside its controller.
+
+
+Nvidia NAND Controller
+----------------------
+
+The device node for a NAND flash controller is as follows:
+
+Optional properties:
+
+nvidia,wp-gpios : GPIO of write-protect line, three cells in the format:
+		phandle, parameter, flags
+nvidia,nand-width : bus width of the NAND device in bits
+
+ - nvidia,nand-timing : Timing parameters for the NAND. Each is in ns.
+	Order is: MAX_TRP_TREA, TWB, Max(tCS, tCH, tALS, tALH),
+	TWHR, Max(tCS, tCH, tALS, tALH), TWH, TWP, TRH, TADL
+
+	MAX_TRP_TREA is:
+		non-EDO mode: Max(tRP, tREA) + 6ns
+		EDO mode: tRP timing
+
+The 'reg' property should provide the chip select used by the flash chip.
+
+
+Example
+-------
+
+nand-controller@0x70008000 {
+	compatible = "nvidia,tegra20-nand";
+	#address-cells = <1>;
+	#size-cells = <0>;
+	nvidia,wp-gpios = <&gpio 59 0>;		/* PH3 */
+	nvidia,nand-width = <8>;
+	nvidia,timing = <26 100 20 80 20 10 12 10 70>;
+	nand@0 {
+		reg = <0>;
+		compatible = "hynix,hy27uf4g2b", "nand-flash";
+		nvidia,page-data-bytes = <2048>;
+		nvidia,tag-ecc-bytes = <4>;
+		nvidia,tag-bytes = <20>;
+		nvidia,data-ecc-bytes = <36>;
+		nvidia,skipped-spare-bytes = <4>;
+		nvidia,page-spare-bytes = <64>;
+	};
+};
-- 
1.7.7.3