Re: [PATCH v3 0/3] clk: renesas: cpg-mssr: add never-disable option

Re: [PATCH v3 0/3] clk: renesas: cpg-mssr: add never-disable option

[Geert Uytterhoeven]

CC clk

Complete series at
http://lore.kernel.org/r/1589214838-18075-1-git-send-email-uli+renesas@fpond.eu

On Mon, May 11, 2020 at 6:34 PM Ulrich Hecht <uli+renesas@fpond.eu> wrote:
> This revision should work more reliably as it keeps the never-disable
> handling in the clock driver instead of relying on the semantics of
> CLK_IGNORE_UNUSED, which still allows clocks to be turned off for power
> management.
>
> This series adds the option for declaring clocks as "never-disable", i.e.
> clocks that will not be turned on if not used, but also not turned off if
> unused. It also enables this option for the RWDT clocks in (almost) all
> SoCs.
>
> The point of this is to allow a WDT that has been enabled by the bootloader
> to survive these events:
>
> - deferred probing of the WDT device, which can lead the clock driver
>   to disable the WDT clock until the WDT is re-probed, giving it a
>   blind spot
> - probe failure in the WDT driver
>
> There are a number of Gen2 and RZ/G1 SoCs that have the RWDT clock declared
> as critical in order to allow SMP bringup code to work. These have been
> left as they are.
>
> CU
> Uli
>
>
> Changes since v2:
> - use the term "never-disable" instead of "ignore-unused"
> - do the handling internally instead of relying on the behavior of
>   CLK_IGNORE_UNUSED
>
> Changes since v1:
> - rename data structures for clarity
> - squash SoC-specific patches into one per family
>
>
> Ulrich Hecht (3):
>   clk: renesas: cpg-mssr: add support for never-disable clocks
>   clk: renesas: rcar-gen3: mark RWDT clocks as never-disable
>   clk: renesas: rzg2: mark RWDT clock as never-disable
>
>  drivers/clk/renesas/r8a774a1-cpg-mssr.c |  5 +++++
>  drivers/clk/renesas/r8a774b1-cpg-mssr.c |  5 +++++
>  drivers/clk/renesas/r8a774c0-cpg-mssr.c |  5 +++++
>  drivers/clk/renesas/r8a7795-cpg-mssr.c  |  6 +++++-
>  drivers/clk/renesas/r8a7796-cpg-mssr.c  |  6 +++++-
>  drivers/clk/renesas/r8a77965-cpg-mssr.c |  5 +++++
>  drivers/clk/renesas/r8a77970-cpg-mssr.c |  6 +++++-
>  drivers/clk/renesas/r8a77980-cpg-mssr.c |  6 +++++-
>  drivers/clk/renesas/r8a77990-cpg-mssr.c |  5 +++++
>  drivers/clk/renesas/r8a77995-cpg-mssr.c |  6 +++++-
>  drivers/clk/renesas/renesas-cpg-mssr.c  | 10 ++++++++++
>  drivers/clk/renesas/renesas-cpg-mssr.h  |  9 +++++++++
>  12 files changed, 69 insertions(+), 5 deletions(-)