[PATCH v4 2/3] reset: tenstorrent: Add reset controller for Atlantis

[Philipp Zabel]

On Fr, 2026-01-30 at 11:50 -0600, Anirudh Srinivasan wrote:
> Adds Atlantis Reset Controller and auxiliary device definitions for
> reset to share same regmap interface as prcm (clock controller).
> 
> This version of the reset controller driver covers resets from the RCPU
> prcm.
> 
> Signed-off-by: Anirudh Srinivasan <asrinivasan at oss.tenstorrent.com>
> ---
>  MAINTAINERS                                |   2 +
>  drivers/reset/Kconfig                      |  11 ++
>  drivers/reset/Makefile                     |   1 +
>  drivers/reset/reset-tenstorrent-atlantis.c | 160 +++++++++++++++++++++++++++++
>  include/soc/tenstorrent/atlantis-prcm.h    |  31 ++++++
>  5 files changed, 205 insertions(+)
> 
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 0fc7bc6d0458..0cde1774567d 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -22537,7 +22537,9 @@ T:	git https://github.com/tenstorrent/linux.git
>  F:	Documentation/devicetree/bindings/clock/tenstorrent,atlantis-prcm.yaml
>  F:	Documentation/devicetree/bindings/riscv/tenstorrent.yaml
>  F:	arch/riscv/boot/dts/tenstorrent/
> +F:	drivers/reset/reset-tenstorrent-atlantis.c
>  F:	include/dt-bindings/clock/tenstorrent,atlantis-prcm.h
> +F:	include/soc/tenstorrent/
>  
>  RISC-V THEAD SoC SUPPORT
>  M:	Drew Fustini <fustini at kernel.org>
> diff --git a/drivers/reset/Kconfig b/drivers/reset/Kconfig
> index 6e5d6deffa7d..cade77717492 100644
> --- a/drivers/reset/Kconfig
> +++ b/drivers/reset/Kconfig
> @@ -324,6 +324,17 @@ config RESET_SUNXI
>  	help
>  	  This enables the reset driver for Allwinner SoCs.
>  
> +config RESET_TENSTORRENT_ATLANTIS
> +	tristate "Tenstorrent atlantis reset driver"
> +	depends on ARCH_TENSTORRENT || COMPILE_TEST
> +	select AUXILIARY_BUS
> +	default ARCH_TENSTORRENT
> +	help
> +	  This enables the driver for the reset controller
> +	  present in the Tenstorrent Atlantis SoC.
> +	  Enable this option to be able to use hardware
> +	  resets on Atalantis based systems.
> +
>  config RESET_TH1520
>  	tristate "T-HEAD TH1520 reset controller"
>  	depends on ARCH_THEAD || COMPILE_TEST
> diff --git a/drivers/reset/Makefile b/drivers/reset/Makefile
> index 9c3e484dfd81..a31959da0a88 100644
> --- a/drivers/reset/Makefile
> +++ b/drivers/reset/Makefile
> @@ -41,6 +41,7 @@ obj-$(CONFIG_RESET_SOCFPGA) += reset-socfpga.o
>  obj-$(CONFIG_RESET_SPACEMIT) += reset-spacemit.o
>  obj-$(CONFIG_RESET_SUNPLUS) += reset-sunplus.o
>  obj-$(CONFIG_RESET_SUNXI) += reset-sunxi.o
> +obj-$(CONFIG_RESET_TENSTORRENT_ATLANTIS) += reset-tenstorrent-atlantis.o
>  obj-$(CONFIG_RESET_TH1520) += reset-th1520.o
>  obj-$(CONFIG_RESET_TI_SCI) += reset-ti-sci.o
>  obj-$(CONFIG_RESET_TI_SYSCON) += reset-ti-syscon.o
> diff --git a/drivers/reset/reset-tenstorrent-atlantis.c b/drivers/reset/reset-tenstorrent-atlantis.c
> new file mode 100644
> index 000000000000..6fe9143ad76c
> --- /dev/null
> +++ b/drivers/reset/reset-tenstorrent-atlantis.c
> @@ -0,0 +1,160 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Tenstorrent Atlantis PRCM Reset Driver
> + *
> + * Copyright (c) 2026 Tenstorrent
> + */
> +
> +#include <dt-bindings/clock/tenstorrent,atlantis-prcm.h>
> +#include <linux/auxiliary_bus.h>
> +#include <linux/reset-controller.h>
> +#include <linux/regmap.h>
> +#include <soc/tenstorrent/atlantis-prcm.h>
> +
> +struct atlantis_reset_data {
> +	u8 bit;
> +	u16 reg;
> +	bool active_low;
> +};
> +
> +struct atlantis_reset_controller_data {
> +	const struct atlantis_reset_data *reset_data;
> +	size_t count;
> +};
> +
> +struct atlantis_reset_controller {
> +	struct reset_controller_dev rcdev;
> +	const struct atlantis_reset_controller_data *data;
> +	struct regmap *regmap;
> +};
> +
> +#define to_atlantis_reset_controller(_rcdev) \
> +	container_of((_rcdev), struct atlantis_reset_controller, rcdev)

Please make this an inline function as well. With that,

Reviewed-by: Philipp Zabel <p.zabel at pengutronix.de>

Since this patch both depends on patch 1 and is a dependency for patch
3, I suppose this should go through the clock tree.

regards
Philipp