RE: [LINUX PATCH v12 1/3] dt-bindings: mtd: arasan: Add device tree binding documentation

Naga Sureshkumar Relli
2018-11-16T13:50:46Z

Hi,

> -----Original Message-----
> From: Michal Simek [mailto:michal.simek@xilinx.com]
> Sent: Friday, November 16, 2018 6:04 PM
> To: Martin Lund <martin.lund@keep-it-simple.com>; Naga Sureshkumar Relli
> <nagasure@xilinx.com>
> Cc: boris.brezillon@bootlin.com; miquel.raynal@bootlin.com; richard@nod.at; David
> Woodhouse <dwmw2@infradead.org>; Brian Norris <computersforpeace@gmail.com>; Marek
> Vašut <marek.vasut@gmail.com>; naga sureshkumar <nagasuresh12@gmail.com>; linux-
> mtd@lists.infradead.org; linux-kernel@vger.kernel.org; robh@kernel.org
> Subject: Re: [LINUX PATCH v12 1/3] dt-bindings: mtd: arasan: Add device tree binding
> documentation
>
> On 16. 11. 18 12:50, Martin Lund wrote:
> > Hi Naga,
> >
> > I've been working on running up the latest kernel (v4.20-rc2) on our
> > custom Xilinx hw board so that I can test the v12 version of your
> > Arasan nand driver.
> >
> > I've managed to get the driver successfully up and running and ready
> > for testing with a Micron MT29F64G08AFAAAWP device. However, setting
> > it up I've found a few inaccuracies in the documentation of the device
> > tree bindings.
> >
> > This is the device configuration that ended up working for me with
> > linux v4.20-rc2:
> >
> > nfc: nand@ff100000 {
> > compatible = "xlnx,zynqmp-nand", "arasan,nfc-v3p10";
> > reg = <0x0 0xff100000 0x0 0x1000>;
> > clock-names = "clk_sys", "clk_flash";
> > clocks = <&clk200>, <&clk100>;
> > interrupt-parent = <&gic>;
> > interrupts = <0 14 4>;
> > #address-cells = <1>;
> > #size-cells = <0>;
> >
> > nand@0 {
> > reg = <0>;
> > nand-ecc-mode = "hw";
> > };
> > };
> >
> > Compared with the example you will notice that "clock-name" should be
> > "clock-names". reg was missing a "0x0".
>
> clock-names and even that names - you are right it is not correct and should be fixed.
Clock-names I will change from "clock-name" to "clock-names".
But I got some review comments previously, to use "sys" instead of "clk_sys" and "flash" instead of "clk_flash".
And I have to change this in driver.
I will update that.

Thanks,
Naga Sureshkumar Relli

>
> Missing 0x0 in reg doesn't matter because it depends on address/size cells.
>
> > I think it is helpful to provide a real-world working example, so you
> > might also consider changing the example "clocks" configuration to
> > clk200/clk100 since there is no clk_misc among the clock sources of
> > any of the xilinx zynqmp board device tree configurations.
>
> Real example is the best normally just c&p from existing dts is the way to go.
> But in connection to clocks it doesn't matter what exactly should be there and I don't think
> there is any consistency in that. Hopefully this will be removed by yaml conversion.
>
> Thanks,
> Michal