Re: [PATCH v8 0/7] Add syscon support for Renesas WDT driver

[Lad, Prabhakar]

Hi all,

On Thu, Oct 1, 2026 at 5:52 PM Prabhakar <prabhakar.csengg@xxxxxxxxx> wrote:
>
> From: Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx>
>
> Hi all,
>
> This series adds syscon support for the Renesas RZ/T2H and RZ/N2H SoCs in
> the WDT driver. The WDTDCR register is part of the CPG/MSSR block for
> which the CPG driver registers SYSC regmap. WDT driver now uses this
> syscon to access the WDTDCR register.
>
> These patches were part of two seprate series [0] and [1], out of which
> certain patches have been queued separately, so I have included rest of
> the patches into this single series.
>
> Merge strategy, as the WDT driver now includes renesas.h header file,
> the driver patches can go via renesas-soc.
>
> Note, patches have been rebased on top of next-20260930.
>
> v7->v8:
> - Dropped patch "watchdog: rzv2h: Drop enabling clocks in the
>   restart handler" addressing Sashiko's comments
>
> v6->v7:
> - Added a new patch to introduce rzt2h_cpg_wdtdcr_count_start() function
> - Added new patch to drop pm_runtime_resume_and_get() &
>   pm_runtime_put_sync() calls while accessing the WDTDCR register.
> - Dropped propagating WDTDCR access errors.
> - Dropped converting WDTDCR handling to regmap as this would require
>   resource address comparison to get WDT index to call
>   rzt2h_cpg_wdtdcr_count_start().
> - Made use of rzt2h_cpg_wdtdcr_count_start() in restart handler
> - Added if regmap is available, use it for WDTDCR access
> - Updated commit message
>
> v5->v6:
> - Used pm_runtime_put_sync() in rzv2h_wdt_stop() function.
> - rebased on top of next-20260922
>
> v4->v5:
> - patch #1 is new addressing Sashiko's comments to avoid potential deadlock
> - patch #4 is new addressing Sashiko's comments
> - Dropped checking rzt2h_wdt_wdtdcr_count_start() return value in
>   restart path.
> - Handled the regmap locking in the driver and introduced nolock
>   version to be used in the restart path.
> - Added review-by tag.
>
> [0] https://lore.kernel.org/all/20260817192540.423994-1-prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx/
> [1] https://lore.kernel.org/all/20260814191415.2110732-1-prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx/
>
> Cheers,
> Prabhakar
>
> Lad Prabhakar (7):
>   clk: renesas: r9a09g077: Add helper to start WDTDCR counter
>   watchdog: rzv2h: Use pm_runtime_put_sync()
>   watchdog: rzv2h: Drop WDTRCR_RSTIRQS define
>   watchdog: rzv2h: Drop runtime PM handling from WDTDCR init
>   watchdog: rzv2h_wdt: Add syscon based WDTDCR access
>   arm64: dts: renesas: r9a09g077: Use CPG/MSSR syscon for WDTDCR access
>   arm64: dts: renesas: r9a09g087: Use CPG/MSSR syscon for WDTDCR access
>
Gentle ping.

Cheers,
Prabhakar

>  arch/arm64/boot/dts/renesas/r9a09g077.dtsi | 24 +++---
>  arch/arm64/boot/dts/renesas/r9a09g087.dtsi | 24 +++---
>  drivers/clk/renesas/r9a09g077-cpg.c        | 35 +++++++--
>  drivers/watchdog/rzv2h_wdt.c               | 85 ++++++++++++++++++----
>  include/linux/clk/renesas.h                |  6 ++
>  5 files changed, 129 insertions(+), 45 deletions(-)
>
> --
> 2.55.0
>