Re: [PATCH 05/11] RISC-V: drivers/iommu/riscv: Add sysfs interface

[Krzysztof Kozlowski]

On 19/07/2023 21:33, Tomasz Jeznach wrote:
> Enable sysfs debug / visibility interface providing restricted
> access to hardware registers.

Please use subject prefixes matching the subsystem. You can get them for
example with `git log --oneline -- DIRECTORY_OR_FILE` on the directory
your patch is touching.

> 
> Signed-off-by: Tomasz Jeznach <tjeznach@xxxxxxxxxxxx>
> ---
>  drivers/iommu/riscv/Makefile      |   2 +-
>  drivers/iommu/riscv/iommu-sysfs.c | 183 ++++++++++++++++++++++++++++++
>  drivers/iommu/riscv/iommu.c       |   7 ++
>  drivers/iommu/riscv/iommu.h       |   2 +
>  4 files changed, 193 insertions(+), 1 deletion(-)
>  create mode 100644 drivers/iommu/riscv/iommu-sysfs.c
> 
> diff --git a/drivers/iommu/riscv/Makefile b/drivers/iommu/riscv/Makefile
> index 38730c11e4a8..9523eb053cfc 100644
> --- a/drivers/iommu/riscv/Makefile
> +++ b/drivers/iommu/riscv/Makefile
> @@ -1 +1 @@
> -obj-$(CONFIG_RISCV_IOMMU) += iommu.o iommu-pci.o iommu-platform.o
> \ No newline at end of file
> +obj-$(CONFIG_RISCV_IOMMU) += iommu.o iommu-pci.o iommu-platform.o iommu-sysfs.o
> \ No newline at end of file

You have this error in multiple places.

> diff --git a/drivers/iommu/riscv/iommu-sysfs.c b/drivers/iommu/riscv/iommu-sysfs.c
> new file mode 100644
> index 000000000000..f038ea8445c5
> --- /dev/null
> +++ b/drivers/iommu/riscv/iommu-sysfs.c
> @@ -0,0 +1,183 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * IOMMU API for RISC-V architected Ziommu implementations.
> + *
> + * Copyright © 2022-2023 Rivos Inc.
> + *
> + * Author: Tomasz Jeznach <tjeznach@xxxxxxxxxxxx>
> + */
> +
> +#include <linux/module.h>
> +#include <linux/kernel.h>
> +#include <linux/compiler.h>
> +#include <linux/iommu.h>
> +#include <linux/platform_device.h>
> +#include <asm/page.h>
> +
> +#include "iommu.h"
> +
> +#define sysfs_dev_to_iommu(dev) \
> +	container_of(dev_get_drvdata(dev), struct riscv_iommu_device, iommu)
> +
> +static ssize_t address_show(struct device *dev,
> +			    struct device_attribute *attr, char *buf)


Where is the sysfs ABI documented?


Best regards,
Krzysztof