Hi Biju,
On Mon, Nov 14, 2022 at 6:05 PM Biju Das <biju.das.jz@xxxxxxxxxxxxxx> wrote:
> > From: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx>
> > On 14/11/2022 17:44, Biju Das wrote:
> > >>>>> If the hardware manual said this is called "foo-whatever-name" or
> > >>>>> "rz85736dfnx2", you would use it as well?
> > >>>>>
> > >>>>> Node names should be generic.
> > >>>
> > >>> I got the following feedback from LSI team.
> > >>>
> > >>> *The reason why we use "configuration" and not "controller" is the
> > >>> possibility that users might take it to mean "control" of system
> > >>> operation (product operation). This unit determines how the whole
> > >>> LSI
> > >> configure to operate LSI, so we use "configuration" for this IP name.
> > >>>
> > >>> As per this it is not a controller. It is a Configuration IP.
> > >>>
> > >>> What should be generic node name for system configuration IP?
> > >>
> > >> Then it's closer to chipid and should be in hwinfo?
> > >
> > > You mean, sys: hwinfo@a3f03000 instead of sys: system-
> > configuration@a3f03000 ??
> >
> > Rather be put in hwinfo directory. Typical name is "chipid", but I don't know
> > if your device is a chipid.
>
> This IP is for sure not a chipid. We can detect SoC version. That is one of the functions provided
> by this IP.
>
> > > Also the same IP block is present on rz/v2ma as well?
> > >
> > > Shall I use the same file renesas,rzv2m-sys.yaml for both r9a09g011-sys and
> > r9a09g055-sys?
Are they sufficiently similar? E.g. we have renesas,rst.yaml for
the various R-Car reset controllers, which have different register
layouts.
If the SoC version register is located at the same offset, it might be
worthwhile to add a family-specific compatible value, too, so the
soc_device driver doesn't have to contain a big list to match against.
> > >> Anyway, you wrote in bindings description: "performs system control",
> > >> so what can I say?
> > >
> > > SYS functional description is as follows.
> > >
> > > The SYS controls the overall configuration of the chip, such as
> >
> > Exactly, it controls, so it is a controller... Anyway, do not introduce your
> > own names, but use something generic. There is no single reference of
> > "system-configuration".
>
> The main functionality of the chip is Bank address configuration,
>
> Bank Address Switching
>
> The SYS has a bank switching register to extend the two higher-order bits of the addresses of the following IP modules
> which have only 32-bit (4-GB) address spaces. It makes 4 or more Gbytes of the address space accessible by switching
> the bank address.
>
> Target unit 1: DRP-AI, eMMC, SDI0/1, ETHER, PCIe, USB, GRP, VCD
> Target unit 2: DMAC
>
> The other control functionalities mentioned in the IP are simple one.
>
> As you said, It is unique IP. Probably in future some other SoC manufactures may come with similar IP for system configuration
> like Bank switching. With Bank switching we can switch from 32 bit ->34 bit addresses.
Sounds like a system-controller to me ;-)
So that looks like the most appropriate generic name.
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
