Re: [PATCH v3 0/9] clk: renesas: rzg2l: Add support for power domains

[Geert Uytterhoeven]

Hi Claudiu,

CC pmdomain, watchdog

On Wed, Apr 10, 2024 at 2:27 PM Claudiu <claudiu.beznea@xxxxxxxxx> wrote:
> Series adds support for power domains on rzg2l driver.
>
> RZ/G2L kind of devices support a functionality called MSTOP (module
> stop/standby). According to hardware manual the module could be switch
> to standby after its clocks are disabled. The reverse order of operation
> should be done when enabling a module (get the module out of standby,
> enable its clocks etc).
>
> In [1] the MSTOP settings were implemented by adding code in driver
> to attach the MSTOP state to the IP clocks. But it has been proposed
> to implement it as power domain. The result is this series.
>
> Along with MSTOP functionality there is also module power down
> functionality (which is currently available only on RZ/G3S). This has
> been also implemented through power domains.
>
> The DT bindings were updated with power domain IDs (plain integers
> that matches the DT with driver data structures). The current DT
> bindings were updated with module IDs for the modules listed in tables
> with name "Registers for Module Standby Mode" (see HW manual) exception
> being RZ/G3S where, due to the power down functionality, the DDR,
> TZCDDR, OTFDE_DDR were also added, to avoid system being blocked due
> to the following lines of code from patch 6/9.
>
> +       /* Prepare for power down the BUSes in power down mode. */
> +       if (info->pm_domain_pwrdn_mstop)
> +               writel(CPG_PWRDN_MSTOP_ENABLE, priv->base + CPG_PWRDN_MSTOP);
>
> Domain IDs were added to all SoC specific bindings.
>
> Thank you,
> Claudiu Beznea
>
> Changes in v3:
> - collected tags
> - dinamically detect if a SCIF is serial console and populate
>   pd->suspend_check
> - dropped patch 09/10 from v2

Thanks for the update!

I have provided my R-b for all patches, and the usual path for these
patches would be for me to queue patches 1-8 in renesas-clk for v6.10,
and to queue 9 in renesas-devel.

However:
  1. I had missed before the pmdomain people weren't CCed before,
     they still might have some comments,
  2. Patch 9 has a hard dependency on the rest of the series, so
     it has to wait one more cycle,
  3. Adding the watchdog domain has a dependency on [1].

2 and 2 may be resolved using an immutable branch.
Are my assumptions correct?

Thanks!

[1] "[PATCH RESEND v8 09/10] watchdog: rzg2l_wdt: Power on the PM
    domain in rzg2l_wdt_restart()"
    https://lore.kernel.org/all/20240410134044.2138310-10-claudiu.beznea.uj@xxxxxxxxxxxxxx

> Changes in v2:
> - addressed review comments
> - dropped:
>     - dt-bindings: clock: r9a09g011-cpg: Add always-on power domain IDs
>     - clk: renesas: r9a07g043: Add initial support for power domains
>     - clk: renesas: r9a07g044: Add initial support for power domains
>     - clk: renesas: r9a09g011: Add initial support for power domains
>     - clk: renesas: r9a09g011: Add initial support for power domains
>     - arm64: dts: renesas: r9a07g043: Update #power-domain-cells = <1>
>     - arm64: dts: renesas: r9a07g044: Update #power-domain-cells = <1>
>     - arm64: dts: renesas: r9a07g054: Update #power-domain-cells = <1>
>     - arm64: dts: renesas: r9a09g011: Update #power-domain-cells = <1>
>   as suggested in the review process
> - dropped "arm64: dts: renesas: rzg3s-smarc-som: Guard the ethernet IRQ
>   GPIOs with proper flags" patch as it was integrated
> - added suspend to RAM support
> - collected tag
>
> [1] https://lore.kernel.org/all/20231120070024.4079344-4-claudiu.beznea.uj@xxxxxxxxxxxxxx/
>
>
> Claudiu Beznea (9):
>   dt-bindings: clock: r9a07g043-cpg: Add power domain IDs
>   dt-bindings: clock: r9a07g044-cpg: Add power domain IDs
>   dt-bindings: clock: r9a07g054-cpg: Add power domain IDs
>   dt-bindings: clock: r9a08g045-cpg: Add power domain IDs
>   dt-bindings: clock: renesas,rzg2l-cpg: Update #power-domain-cells =
>     <1> for RZ/G3S
>   clk: renesas: rzg2l: Extend power domain support
>   clk: renesas: r9a08g045: Add support for power domains
>   clk: renesas: rzg2l-cpg: Add suspend/resume support for power domains
>   arm64: dts: renesas: r9a08g045: Update #power-domain-cells = <1>
>
>  .../bindings/clock/renesas,rzg2l-cpg.yaml     |  18 +-
>  arch/arm64/boot/dts/renesas/r9a08g045.dtsi    |  20 +-
>  drivers/clk/renesas/r9a08g045-cpg.c           |  61 ++++
>  drivers/clk/renesas/rzg2l-cpg.c               | 269 +++++++++++++++++-
>  drivers/clk/renesas/rzg2l-cpg.h               |  77 +++++
>  include/dt-bindings/clock/r9a07g043-cpg.h     |  52 ++++
>  include/dt-bindings/clock/r9a07g044-cpg.h     |  58 ++++
>  include/dt-bindings/clock/r9a07g054-cpg.h     |  58 ++++
>  include/dt-bindings/clock/r9a08g045-cpg.h     |  70 +++++
>  9 files changed, 659 insertions(+), 24 deletions(-)

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68korg

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