[PATCH v2 1/2] dt-bindings: pinctrl: airoha: Add EN7581 pinctrl controller

[Benjamin Larsson]

Hi.

On 26/08/2024 19:07, Conor Dooley wrote:
> To clarify the hw architecture we are discussing about 3 memory regions:
>> - chip_scu: <0x1fa20000 0x384>
>> - scu: <0x1fb00020 0x94c>
>                    ^
> I'm highly suspicious of a register region that begins at 0x20. What is
> at 0x1fb00000?

Unknown, no documentation of those registers.


>
>> - gpio: <0x1fbf0200 0xbc>
> Do you have a link to the register map documentation for this hardware?

There is no public documentation, what is available is the current 
driver source and this (less useful) partial map here:

https://github.com/gchmiel/en7512_kernel5/blob/master/linux-5-new/arch/mips/include/asm/tc3162/tc3162.h#L860

Registers with FMAP and FLAP are parts of the PWM functionality.

>
>> The memory regions above are used by the following IC blocks:
>> - clock: chip_scu and scu
> What is the differentiation between these two different regions? Do they
> provide different clocks? Are registers from both of them required in
> order to provide particular clocks?

chip-scu contains the registers the clock driver handles. But scu has 
registers with the word clock in the description but both regions does 
not seem to be needed for a specific clock.

chip-scu contains pinctrl, iomux and clocks

scu contains random bits and functional muxes for serdes

>
>> - pinctrl (io-muxing/gpio_chip/irq_chip): chip_scu and gpio
> Ditto here. Are these actually two different sets of iomuxes, or are
> registers from both required to mux a particular pin?

io-muxes for pins are done in chip-scu, pwm muxing is done in the gpio 
register range together with chip-scu (ensure there are no conflicts).

MvH

Benjamin Larsson