Re: [PATCH v2 13/14] reset: starfive: Add StarFive JH7110 reset driver

From: Emil Renner Berthing
Date: Fri Nov 18 2022 - 12:15:19 EST


On Fri, 18 Nov 2022 at 02:06, Hal Feng <hal.feng@xxxxxxxxxxxxxxxx> wrote:
>
> Add auxiliary driver to support StarFive JH7110 system
> and always-on resets.
>
> Signed-off-by: Hal Feng <hal.feng@xxxxxxxxxxxxxxxx>
> ---
> drivers/reset/starfive/Kconfig | 8 +++
> drivers/reset/starfive/Makefile | 1 +
> .../reset/starfive/reset-starfive-jh7110.c | 67 +++++++++++++++++++
> .../reset/starfive/reset-starfive-jh71x0.h | 7 ++
> 4 files changed, 83 insertions(+)
> create mode 100644 drivers/reset/starfive/reset-starfive-jh7110.c
>
> diff --git a/drivers/reset/starfive/Kconfig b/drivers/reset/starfive/Kconfig
> index 9d15c4110e40..fab1a081af17 100644
> --- a/drivers/reset/starfive/Kconfig
> +++ b/drivers/reset/starfive/Kconfig
> @@ -10,3 +10,11 @@ config RESET_STARFIVE_JH7100
> default SOC_STARFIVE
> help
> This enables the reset controller driver for the StarFive JH7100 SoC.
> +
> +config RESET_STARFIVE_JH7110
> + bool "StarFive JH7110 Reset Driver"
> + depends on AUXILIARY_BUS && CLK_STARFIVE_JH7110_SYS
> + select RESET_STARFIVE_JH71X0
> + default CLK_STARFIVE_JH7110_SYS
> + help
> + This enables the reset controller driver for the StarFive JH7110 SoC.
> diff --git a/drivers/reset/starfive/Makefile b/drivers/reset/starfive/Makefile
> index f6aa12466fad..7a44b66fb9d5 100644
> --- a/drivers/reset/starfive/Makefile
> +++ b/drivers/reset/starfive/Makefile
> @@ -2,3 +2,4 @@
> obj-$(CONFIG_RESET_STARFIVE_JH71X0) += reset-starfive-jh71x0.o
>
> obj-$(CONFIG_RESET_STARFIVE_JH7100) += reset-starfive-jh7100.o
> +obj-$(CONFIG_RESET_STARFIVE_JH7110) += reset-starfive-jh7110.o
> diff --git a/drivers/reset/starfive/reset-starfive-jh7110.c b/drivers/reset/starfive/reset-starfive-jh7110.c
> new file mode 100644
> index 000000000000..00f3b4ecfb02
> --- /dev/null
> +++ b/drivers/reset/starfive/reset-starfive-jh7110.c
> @@ -0,0 +1,67 @@
> +// SPDX-License-Identifier: GPL-2.0-or-later
> +/*
> + * Reset driver for the StarFive JH7110 SoC
> + *
> + * Copyright (C) 2022 StarFive Technology Co., Ltd.
> + * Copyright (C) 2022 Hal Feng <hal.feng@xxxxxxxxxxxxxxxx>
> + */
> +
> +#include <linux/auxiliary_bus.h>
> +
> +#include "reset-starfive-jh71x0.h"
> +
> +#include <dt-bindings/reset/starfive-jh7110.h>
> +
> +static int jh7110_reset_probe(struct auxiliary_device *adev,
> + const struct auxiliary_device_id *id)
> +{
> + struct reset_info *info = (struct reset_info *)(id->driver_data);
> + void __iomem *base = dev_get_drvdata(adev->dev.parent);
> +
> + if (!info || !base)
> + return -ENODEV;
> +
> + return reset_starfive_jh71x0_register(&adev->dev, adev->dev.parent->of_node,
> + base + info->assert_offset,
> + base + info->status_offset,
> + info->asserted,
> + info->nr_resets,
> + false);
> +}
> +
> +static const struct reset_info jh7110_sys_info = {
> + .nr_resets = JH7110_SYSRST_END,
> + .assert_offset = 0x2F8,
> + .status_offset = 0x308,
> + .asserted = NULL,
> +};
> +
> +static const struct reset_info jh7110_aon_info = {
> + .nr_resets = JH7110_AONRST_END,
> + .assert_offset = 0x38,
> + .status_offset = 0x3C,
> + .asserted = NULL,
> +};

It doesn't seem like syscrg, aoncrg or stgcrg have any inverted lines.
Do you know if any other CRGs do? If not you can just leave out the
.asserted member and always pass NULL.

> +static const struct auxiliary_device_id jh7110_reset_ids[] = {
> + {
> + .name = "clk_starfive_jh71x0.reset-sys",
> + .driver_data = (kernel_ulong_t)&jh7110_sys_info,
> + },
> + {
> + .name = "clk_starfive_jh71x0.reset-aon",
> + .driver_data = (kernel_ulong_t)&jh7110_aon_info,
> + },
> + { /* sentinel */ }
> +};
> +MODULE_DEVICE_TABLE(auxiliary, jh7110_reset_ids);
> +
> +static struct auxiliary_driver jh7110_reset_driver = {
> + .probe = jh7110_reset_probe,
> + .id_table = jh7110_reset_ids,
> +};
> +module_auxiliary_driver(jh7110_reset_driver);
> +
> +MODULE_DESCRIPTION("StarFive JH7110 Reset Driver");
> +MODULE_AUTHOR("Hal Feng <hal.feng@xxxxxxxxxxxxxxxx>");
> +MODULE_LICENSE("GPL");
> diff --git a/drivers/reset/starfive/reset-starfive-jh71x0.h b/drivers/reset/starfive/reset-starfive-jh71x0.h
> index e6b27110de48..63a94ee1b395 100644
> --- a/drivers/reset/starfive/reset-starfive-jh71x0.h
> +++ b/drivers/reset/starfive/reset-starfive-jh71x0.h
> @@ -6,6 +6,13 @@
> #ifndef __RESET_STARFIVE_JH71X0_H
> #define __RESET_STARFIVE_JH71X0_H
>
> +struct reset_info {
> + unsigned int nr_resets;
> + unsigned int assert_offset;
> + unsigned int status_offset;
> + const u32 *asserted;
> +};

This struct isn't used outside of reset-starfive-jh7110.c, so no need
to define it in this header.
Also consider calling it jh7110_reset_info so it blends in with the
functions defined in that file.

> int reset_starfive_jh71x0_register(struct device *dev, struct device_node *of_node,
> void __iomem *assert, void __iomem *status,
> const u32 *asserted, unsigned int nr_resets,
> --
> 2.38.1
>