Re: [PATCH 2/4] ARM: dts: da850: Add an aemif node

From: Karl Beldan
Date: Wed Aug 10 2016 - 15:00:31 EST


On Wed, Aug 10, 2016 at 01:32:03PM +0530, Sekhar Nori wrote:
> On Wednesday 10 August 2016 01:18 PM, Sekhar Nori wrote:
> > On Tuesday 09 August 2016 10:45 PM, Karl Beldan wrote:
> >> Currently the davinci da8xx boards use the mach-davinci aemif code.
> >> Instantiating an aemif node into the DT allows to use the ti-aemif
> >> memory driver and is another step to better DT support.
> >> Also it will allow to properly pass the emif timings via DT.
> >>
> >> Signed-off-by: Karl Beldan <kbeldan@xxxxxxxxxxxx>
> >> ---
> >> arch/arm/boot/dts/da850.dtsi | 10 ++++++++++
> >> 1 file changed, 10 insertions(+)
> >>
> >> diff --git a/arch/arm/boot/dts/da850.dtsi b/arch/arm/boot/dts/da850.dtsi
> >> index bc10e7e..f62928c 100644
> >> --- a/arch/arm/boot/dts/da850.dtsi
> >> +++ b/arch/arm/boot/dts/da850.dtsi
> >> @@ -411,6 +411,16 @@
> >> dma-names = "tx", "rx";
> >> };
> >> };
> >> + aemif: aemif@68000000 {
> >> + compatible = "ti,da850-aemif";
> >> + #address-cells = <2>;
> >> + #size-cells = <1>;
> >> +
> >> + reg = <0x68000000 0x00008000>;
> >> + ranges = <0 0 0x60000000 0x08000000
> >> + 1 0 0x68000000 0x00008000>;
> >> + status = "disabled";
> >> + };
> >> nand_cs3@62000000 {
> >> compatible = "ti,davinci-nand";
> >> reg = <0x62000000 0x807ff
> >
> > The nand node should be part of aemif node like it is done for keystone
> > boards.
>
> Actually, can you move the nand node out of da850.dtsi completely. Its
> much better to keep da850.dtsi restricted to soc-internal devices and
> keep the board level devices like NAND flash in <board>.dts file.
>
> Similarly, can you move the NAND pinmux definitions too to the
> da850-evm.dts file?
>
> There is advantage in keeping common pinmux definitions in da850.dtsi so
> each board doe not have to repeat them. But AEMIF is an exception as its
> usage can really be varied (NAND, NOR, SRAM, other). Plus, different
> boards are likely to use different chip selects so coming up with some
> pinmux definitions which will be reused widely is really unlikely.
>
This is exactly what I just did for the LCDK.
If everybody is happy with it I will do the same for the evm as I put it
in the cover letter.

Karl