From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Tue, 10 May 2016 14:22:46 +0200 From: Boris Brezillon To: Jorge Ramirez Cc: computersforpeace@gmail.com, dwmw2@infradead.org, matthias.bgg@gmail.com, robh@kernel.org, linux-mtd@lists.infradead.org, xiaolei.li@mediatek.com, linux-mediatek@lists.infradead.org, erin.lo@mediatek.com, daniel.thompson@linaro.org, blogic@openwrt.org Subject: Re: [PATCH v4 1/2] mtd: mediatek: device tree docs for MTK Smart Device Gen1 NAND Message-ID: <20160510142246.264cb986@bbrezillon> In-Reply-To: <5731CCA5.5070603@linaro.org> References: <1461946642-1842-1-git-send-email-jorge.ramirez-ortiz@linaro.org> <1461946642-1842-2-git-send-email-jorge.ramirez-ortiz@linaro.org> <20160506153816.7ca581ac@bbrezillon> <5731CCA5.5070603@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Tue, 10 May 2016 07:57:25 -0400 Jorge Ramirez wrote: > On 05/06/2016 09:38 AM, Boris Brezillon wrote: > > Hi Jorge, > > > > On Fri, 29 Apr 2016 12:17:21 -0400 > > Jorge Ramirez-Ortiz wrote: > > > >> This patch adds documentation support for Smart Device Gen1 type of > >> NAND controllers. > >> > >> Signed-off-by: Jorge Ramirez-Ortiz > >> --- > >> Documentation/devicetree/bindings/mtd/mtk-nand.txt | 161 +++++++++++++++++++++ > >> 1 file changed, 161 insertions(+) > >> create mode 100644 Documentation/devicetree/bindings/mtd/mtk-nand.txt > >> > >> diff --git a/Documentation/devicetree/bindings/mtd/mtk-nand.txt b/Documentation/devicetree/bindings/mtd/mtk-nand.txt > >> new file mode 100644 > >> index 0000000..175767d > >> --- /dev/null > >> +++ b/Documentation/devicetree/bindings/mtd/mtk-nand.txt > > [...] > > > >> + > >> +Children nodes properties: > >> +- reg: Chip Select Signal, default 0. > >> + Set as reg = <0>, <1> when need 2 CS. > >> +Optional: > >> +- nand-on-flash-bbt: Store BBT on NAND Flash. > >> +- nand-ecc-mode: the NAND ecc mode (check driver for supported modes) > >> +- nand-ecc-step-size: Number of data bytes covered by a single ECC step. > >> + The controller only supports 512 and 1024. > >> + For large page NANDs ther recommended value is 1024. > >> +- nand-ecc-strength: Number of bits to correct per ECC step. > >> + The valid values that the controller supports are: 4, 6, > >> + 8, 10, 12, 14, 16, 18, 20, 22, 24, 28, 32, 36, 40, 44, > >> + 48, 52, 56, 60. > >> + The strength should be calculated as follows: > >> + E = (S - F) * 8 / 14 > >> + S = O / (P / Q) > >> + E :nand-ecc-strength; > >> + S :spare size per sector; > >> + F : FDM size, should be in the range [1,8]. > >> + It is used to store free oob data. > >> + O : oob size; > >> + P : page size; > >> + Q :nand-ecc-step-size > >> + If the result does not match any one of the listed > >> + choices above, please select the smaller valid value from > >> + the list. > >> + (otherwise the driver will do the clamping at runtime). > >> +- vmch-supply: NAND power supply. > > Where is this supply name coming from? I most datasheets I see Vdd or > > Vcc, but nothing close to Vmch. > > > > > > > > um yes we are removing this since we dont use it (it is the NAND vcc on > some other MTK platform to do power management via regulator). > Ok, no problem. Actually it's yet another property that should be described in the generic binding doc. -- Boris Brezillon, Free Electrons Embedded Linux and Kernel engineering http://free-electrons.com