[PATCH] ramips: set Netgear R6220 MAC NVMEM cell directly in the part node

[Rafał Miłecki]

On 2023-07-14 11:57, Felix Baumann wrote:
> Am 14. Juli 2023 10:26:33 MESZ schrieb "Rafał Miłecki" 
> <zajec5 at gmail.com>:
>> On 9.05.2023 18:21, Felix Baumann wrote:
>>> Am 9. Mai 2023 15:29:48 MESZ schrieb "Rafał Miłecki" 
>>> <zajec5 at gmail.com>:
>>>> From: Rafał Miłecki <rafal at milecki.pl>
>>>> 
>>>> There is no need to use reference if original node it specified in
>>>> exactly the same file. This is a minor cleanup simplifying DTS code.
>>>> 
>>>> Signed-off-by: Rafał Miłecki <rafal at milecki.pl>
>>>> ---
>>>> .../linux/ramips/dts/mt7621_netgear_r6220.dts  | 18 
>>>> ++++++++----------
>>>> 1 file changed, 8 insertions(+), 10 deletions(-)
>>>> 
>>>> diff --git a/target/linux/ramips/dts/mt7621_netgear_r6220.dts 
>>>> b/target/linux/ramips/dts/mt7621_netgear_r6220.dts
>>>> index 0f476ef060..7bb49c15b4 100644
>>>> --- a/target/linux/ramips/dts/mt7621_netgear_r6220.dts
>>>> +++ b/target/linux/ramips/dts/mt7621_netgear_r6220.dts
>>>> @@ -42,9 +42,17 @@
>>>> 		};
>>>> 
>>>> 		factory: partition at 2e00000 {
>>> 
>>> The "factory" reference could be probably be dropped as well. 
>>> Proposed changes look good to me.
>> 
>> Actually it can't be dropped. While it's a bit counter-intuitive, that
>> label is used in a *parent* DTS file mt7621_netgear_sercomm_ayx.dtsi .
> 
> Hello Rafał,
> 
> I was under the strong impression that dts(i) files could only get
> reference from the same file or parents but not childs. I remember
> reading a few exchanges by Ansuel, I think, that mentioned this.
> I might be mixing two topics here, but was this (intended to be) fixed
> by dynamic partitions or something like that?
> 
> Are you certain the eeprom is loaded successfully?
> 
> Aren't dts(i) files read from top to bottom?

I just verified that and it works.

First I decompiled .dtb from the latest "master" branch with:
dtc -I dtb -O dts -o r6220.dts 
build_dir/target-mipsel_24kc_musl/linux-ramips_mt7621/image-mt7621_netgear_r6220.dtb

Then I opened r6220.dts and analyzed it.

My MAC cell looks like this:

macaddr at 4 {
	compatible = "mac-base";
	reg = <0x04 0x06>;
	#nvmem-cell-cells = <0x01>;
	phandle = <0x13>;
};


Then my Ethernet controller nodes look like that:

mac at 0 {
	compatible = "mediatek,eth-mac";
	reg = <0x00>;
	nvmem-cells = <0x13 0x00>;
	nvmem-cell-names = "mac-address";
	(...)
};

mac at 1 {
	compatible = "mediatek,eth-mac";
	reg = <0x01>;
	status = "okay";
	nvmem-cells = <0x13 0x01>;
	nvmem-cell-names = "mac-address";
	(...)
};

As you can see both reference phandle 0x13 so that looks all good.