Re: [PATCH 1/3] arm64: dts: ti: Add GPMC NAND support

Nishanth Menon
2023-09-15T12:23:23Z

On 14:53-20230915, Nitin Yadav wrote:
>
>
> On 14/09/23 21:34, Nishanth Menon wrote:
> > On 14:56-20230914, Nitin Yadav wrote:
> >> Hi Krzysztof,
> >>
> >> On 14/09/23 11:57, Krzysztof Kozlowski wrote:
> >>> On 13/09/2023 13:47, Nitin Yadav wrote:
> >>>> Add support for AM62Q NAND card: X8 NAND EXPANSION
> >>>> BOARD card (PROC143E1) for AM62x LP SK board.
> >
> > Commit message is all too wrong as well. Sigh.
> >
> >>>>
> >>>> Signed-off-by: Nitin Yadav <n-yadav@ti.com>
> >>>> ---
> >>>> arch/arm64/boot/dts/ti/k3-am62-main.dtsi | 29 ++++++++++++++++++++++++
> >>>> arch/arm64/boot/dts/ti/k3-am62.dtsi | 2 ++
> >>>> 2 files changed, 31 insertions(+)
> >>>>
> >>>> diff --git a/arch/arm64/boot/dts/ti/k3-am62-main.dtsi b/arch/arm64/boot/dts/ti/k3-am62-main.dtsi
> >>>> index 284b90c94da8..e93e79d8083f 100644
> >>>> --- a/arch/arm64/boot/dts/ti/k3-am62-main.dtsi
> >>>> +++ b/arch/arm64/boot/dts/ti/k3-am62-main.dtsi
> >>>> @@ -955,4 +955,33 @@ mcasp2: audio-controller@2b20000 {
> >>>> power-domains = <&k3_pds 192 TI_SCI_PD_EXCLUSIVE>;
> >>>> status = "disabled";
> >>>> };
> >>>> + gpmc0: memory-controller@3b000000 {
> >>>> + status = "disabled";
> >>>
> >>> status is never first in DTSI. Really, where did you see such code?
> >> Thank for pointing out, Will send a revised version.
> >
> > GPMC is not functional without board specific interface configuration
> > such as pinmux. this approach, in fact is all over the place now and
> > discussed in the mailing list multiple times now.
> >
> > What is missing here is the documentation of the constraints as to why
> > it is set as disabled by default.

> gpmc nand is only am62x lp sk in am62x series. it has pinmux conflict
> with macsp1, so disabling gpmc & elm by default for other am62 series.
> For am62x lpsk in overlay macsp1 is disabled.

When introducing a patch for SoC dtsi - explain in commit message and
code comments from the SoC's perspective, not the specific board
perspective.

--
Regards,
Nishanth Menon
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