Re: [PATCH 0/7] rtc: sun6i: Add support for Allwinner A733 SoC

[Jernej Škrabec]

Hi!

Dne sreda, 21. januar 2026 ob 11:59:06 Srednjeevropski standardni čas je Junhui Liu napisal(a):
> Add support for the Allwinner A733 RTC and its internal Clock Control
> Unit (CCU). Reuse the rtc-sun6i rtc driver while introducing a new
> SoC-specific RTC CCU driver to handle the hardware's evolved clock
> structure.
> 
> To facilitate this addition and improve driver modularity, transition
> the binding between the RTC and its internal CCU from direct
> cross-subsystem function calls to the auxiliary bus. Also extract shared
> IOSC and 32kHz clock logic into a standalone ccu_rtc module for reuse
> across newer SoC generations.
> 
> The A733 implementation supports hardware detection of three external
> crystal frequencies (19.2MHz, 24MHz and 26MHz), which is represented in
> the driver via read-only mux operations. Implement logic to derive a
> normalized 32kHz reference from these DCXO sources using fixed
> pre-dividers. Additionally, provide several new DCXO gate clocks for
> peripherals, including SerDes, HDMI, and UFS.

This work looks nice, but I have some questions/comments:
- you're missing RTC SPI clock, which is needed for RTC, at least according
  to vendor 5.15 DT. Could it be that this bit set by vendor U-Boot so you
  missed it during testing? Manual says that it's disabled by default.
- Vendor DT has strange RTC CCU phandles for UFS and HDMI. In first case
  uses RTC wakeup and in second DCXO, which doesn't make any sense. Did you
  do any experimentation with these clocks? It wouldn't be the first time
  that either code or manual contained some kind of error.

Btw, switch last two patches. With current order during bisection you would
get a complaint that A733 RTC CCU driver is not present.

Best regards,
Jernej