From mboxrd@z Thu Jan 1 00:00:00 1970 From: Miquel Raynal Subject: [PATCH v2 1/5] dt-bindings: mtd: add Marvell NAND controller documentation Date: Tue, 19 Dec 2017 14:29:38 +0100 Message-ID: <20171219132942.27433-2-miquel.raynal@free-electrons.com> References: <20171219132942.27433-1-miquel.raynal@free-electrons.com> Return-path: In-Reply-To: <20171219132942.27433-1-miquel.raynal-wi1+55ScJUtKEb57/3fJTNBPR1lH4CV8@public.gmane.org> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: David Woodhouse , Brian Norris , Boris Brezillon , Marek Vasut , Richard Weinberger , Cyrille Pitchen , Rob Herring , Mark Rutland , Jason Cooper , Andrew Lunn , Gregory Clement , Sebastian Hesselbarth , Russell King , Daniel Mack , Haojian Zhuang , Robert Jarzmik , Eric Miao , Catalin Marinas Cc: linux-mtd-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, Thomas Petazzoni , Antoine Tenart , Nadav Haklai , Miquel Raynal , Ofer Heifetz , Hanna Hawa , Neta Zur Hershkovits , Willy Tarreau , =?UTF-8?q?Sean=20Nyekj=C3=A6r?= List-Id: devicetree@vger.kernel.org Document the legacy and the new bindings for Marvell NAND controller. The pxa3xx_nand.c driver does only support legacy bindings, which are incomplete and inaccurate. A rework of this controller (called marvell_nand.c) does support both. Signed-off-by: Miquel Raynal --- .../devicetree/bindings/mtd/marvell-nand.txt | 123 +++++++++++++++++++++ 1 file changed, 123 insertions(+) create mode 100644 Documentation/devicetree/bindings/mtd/marvell-nand.txt diff --git a/Documentation/devicetree/bindings/mtd/marvell-nand.txt b/Documentation/devicetree/bindings/mtd/marvell-nand.txt new file mode 100644 index 000000000000..aa6a1ed045b2 --- /dev/null +++ b/Documentation/devicetree/bindings/mtd/marvell-nand.txt @@ -0,0 +1,123 @@ +Marvell NAND Flash Controller (NFC) + +Required properties: +- compatible: can be one of the following: + * "marvell,armada-8k-nand-controller" + * "marvell,armada370-nand-controller" + * "marvell,pxa3xx-nand-controller" + * "marvell,armada-8k-nand" (deprecated) + * "marvell,armada370-nand" (deprecated) + * "marvell,pxa3xx-nand" (deprecated) + Compatibles marked deprecated support only the old bindings described + at the bottom. +- reg: NAND flash controller memory area. +- #address-cells: shall be set to 1. Encode the NAND CS. +- #size-cells: shall be set to 0. +- interrupts: shall define the NAND controller interrupt. +- clocks: shall reference the NAND controller clock. +- marvell,system-controller: Set to retrieve the syscon node that handles + NAND controller related registers (only required with the + "marvell,armada-8k-nand[-controller]" compatibles). + +Optional properties: +- label: see partition.txt. New platforms shall omit this property. +- dmas: shall reference DMA channel associated to the NAND controller. + This property is only used with "marvell,pxa3xx-nand[-controller]" + compatible strings. +- dma-names: shall be "rxtx". + This property is only used with "marvell,pxa3xx-nand[-controller]" + compatible strings. + +Optional children nodes: +Children nodes represent the available NAND chips. + +Required properties: +- reg: shall contain the native Chip Select ids (0-3) +- marvell,rb: shall contain the native Ready/Busy ids (0-1) + +Optional properties: +- marvell,nand-keep-config: orders the driver not to take the timings + from the core and leaving them completely untouched. Bootloader + timings will then be used. +- label: MTD name. +- nand-on-flash-bbt: see nand.txt. +- nand-ecc-mode: see nand.txt. Will use hardware ECC if not specified. +- nand-ecc-algo: see nand.txt. This property may be added when using + hardware ECC for clarification but will be ignored by the driver + because ECC mode is chosen depending on the page size and the strength + required by the NAND chip. This value may be overwritten with + nand-ecc-strength property. +- nand-ecc-strength: see nand.txt. +- nand-ecc-step-size: see nand.txt. This has no effect and will be + ignored by the driver when using hardware ECC because Marvell's NAND + flash controller does use fixed strength (1-bit for Hamming, 16-bit + for BCH), so the step size will shrink or grow in order to fit the + required strength. Step sizes are not completely random for all and + follow certain patterns described in AN-379, "Marvell SoC NFC ECC". + +See Documentation/devicetree/bindings/mtd/nand.txt for more details on +generic bindings. + + +Example: +nand_controller: nand-controller@d0000 { + compatible = "marvell,armada370-nand-controller"; + reg = <0xd0000 0x54>; + #address-cells = <1>; + #size-cells = <0>; + interrupts = ; + clocks = <&coredivclk 0>; + + nand@0 { + reg = <0>; + label = "main-storage"; + marvell,rb = <0>; + nand-ecc-mode = "hw"; + marvell,nand-keep-config; + nand-on-flash-bbt; + nand-ecc-strength = <4>; + nand-ecc-step-size = <512>; + + partitions { + compatible = "fixed-partitions"; + #address-cells = <1>; + #size-cells = <1>; + + partition@0 { + label = "Rootfs"; + reg = <0x00000000 0x40000000>; + }; + }; + }; +}; + + +Note on legacy bindings: One can find, in not-updated device trees, +bindings slightly differents than described above with other properties +described below as well as the partitions node at the root of a so +called "nand" node (without clear controller/chip separation). + +Legacy properties: +- marvell,nand-enable-arbiter: To enable the arbiter, all boards blindly + used it, this bit was set by the bootloader for many boards and even if + it is marked reserved in several datasheets, it might be needed to set + it (otherwise it is harmless) so whether or not this property is set, + the bit is selected by the driver. +- num-cs: Number of chip-select lines to use, all boards blindly set 1 + to this and for a reason, other values would have failed. The value of + this property is ignored. + +Example: + + nand0: nand@43100000 { + compatible = "marvell,pxa3xx-nand"; + reg = <0x43100000 90>; + interrupts = <45>; + dmas = <&pdma 97 0>; + dma-names = "rxtx"; + #address-cells = <1>; + marvell,nand-keep-config; + marvell,nand-enable-arbiter; + num-cs = <1>; + /* Partitions (optional) */ + }; -- 2.11.0 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html