Re: [PATCH v6 3/8] clk: sunxi-ng: a733: Add PRCM CCU

[Enzo Adriano <enzo.adriano.code@gmail.com>]

Hi Junhui,

On Fri, Oct 09, 2026 at 11:52:08PM +0800, Junhui Liu wrote:
> +static SUNXI_CCU_P_DATA_WITH_MUX_GATE(r_cpu_timer0, "r-timer0", r_apb_parents, 0x100,
> +				      1, 3,	/* P */
> +				      4, 3,	/* mux */
> +				      BIT(0),	/* gate */
> +				      0);

On a Cubie A7S with vendor boot firmware, v6 reaches a Linux shell but
stalls at warm reboot. The system-controller firmware uses the R-domain
timer and mailboxes without Linux clock consumers, so disabling these
clocks as unused can leave its services unavailable.

Could you consider marking r-timer0, bus-r-timer, bus-r-riscv and
bus-r-msgbox here, and bus-msgbox0 in 7/8, CLK_IS_CRITICAL in the next
revision? My standalone patch has the diff, firmware references and
board results:
https://lore.kernel.org/r/20261031020640-263f7b05-a7s-clock@gmail.com

With those five flags, two RAM boots of my A7S integration completed
warm reboots without clk_ignore_unused, and all five clocks reported
enabled. That is one board on vendor firmware. Vinicius reported native
PSCI reboot working on an A7Z without local critical flags on
bus-r-riscv and bus-r-msgbox, with TF-A and U-Boot built from source, so
the boot chain may matter. I haven't tested suspend, or shown that each
of the five flags is needed on its own.

Thanks,
Enzo