Re: [PATCH v4 13/19] reset: starfive: Add StarFive JH7110 reset driver

Emil Renner Berthing
2023-02-21T15:33:38Z

On Tue, 21 Feb 2023 at 03:47, Hal Feng <hal.feng@starfivetech.com> wrote:
>
> Add auxiliary driver to support StarFive JH7110 system
> and always-on resets.
>
> Reported-by: kernel test robot <lkp@intel.com>
> Signed-off-by: Hal Feng <hal.feng@starfivetech.com>
> ---
> drivers/reset/starfive/Kconfig | 8 +++
> drivers/reset/starfive/Makefile | 1 +
> .../reset/starfive/reset-starfive-jh7110.c | 64 +++++++++++++++++++
> .../reset/starfive/reset-starfive-jh71x0.h | 6 ++
> 4 files changed, 79 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..83577d1b7fc6
> --- /dev/null
> +++ b/drivers/reset/starfive/reset-starfive-jh7110.c
> @@ -0,0 +1,64 @@
> +// SPDX-License-Identifier: GPL-2.0-or-later
> +/*
> + * Reset driver for the StarFive JH7110 SoC
> + *
> + * Copyright (C) 2022 StarFive Technology Co., Ltd.
> + */
> +
> +#include <linux/auxiliary_bus.h>
> +
> +#include "reset-starfive-jh71x0.h"
> +
> +#include <dt-bindings/reset/starfive,jh7110-crg.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 = (void __iomem **)dev_get_drvdata(adev->dev.parent);

Hi Hal,

I saw the kernel test robot complain about this, but I still wonder if
the extra level of indirection is really needed. Isn't it enough to
just add the explicit casts, so

dev_set_drvdata(priv->dev, (void *)priv->base);

in the clock drivers and here just

void __iomem *base = (void __iomem *)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,
> + NULL,
> + info->nr_resets,
> + NULL);
> +}
> +
> +static const struct reset_info jh7110_sys_info = {
> + .nr_resets = JH7110_SYSRST_END,
> + .assert_offset = 0x2F8,
> + .status_offset = 0x308,
> +};
> +
> +static const struct reset_info jh7110_aon_info = {
> + .nr_resets = JH7110_AONRST_END,
> + .assert_offset = 0x38,
> + .status_offset = 0x3C,
> +};
> +
> +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_AUTHOR("Hal Feng <hal.feng@starfivetech.com>");
> +MODULE_DESCRIPTION("StarFive JH7110 reset driver");
> +MODULE_LICENSE("GPL");
> diff --git a/drivers/reset/starfive/reset-starfive-jh71x0.h b/drivers/reset/starfive/reset-starfive-jh71x0.h
> index db7d39a87f87..e485472e1adc 100644
> --- a/drivers/reset/starfive/reset-starfive-jh71x0.h
> +++ b/drivers/reset/starfive/reset-starfive-jh71x0.h
> @@ -6,6 +6,12 @@
> #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;
> +};

As far as I can tell this struct isn't used anywhere but in
reset-starfive-jh7110.c. If so just move it there, and in any case
please call it something less generic like struct jh7110_reset_info.

> +
> 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
>