[PATCH i-g-t v2 1/4] lib/xe/xe_sriov_debugfs: Add helper to read VF's configuration data

[Bernatowicz, Marcin]

On 2/7/2025 10:40 AM, Lukasz Laguna wrote:
> Add helper allowing to read configuration data that VF queried from GuC
> during probe.
> 
> v2:
>   - remove redundant fd closing (Marcin)
>   - move helper to xe_sriov_debugfs lib (Marcin)
> 
> Signed-off-by: Lukasz Laguna <lukasz.laguna at intel.com>
> Reviewed-by: Satyanarayana K V P <satyanarayana.k.v.p at intel.com>
> ---
>   lib/xe/xe_sriov_debugfs.c | 78 +++++++++++++++++++++++++++++++++++++++
>   lib/xe/xe_sriov_debugfs.h |  5 +++
>   2 files changed, 83 insertions(+)
> 
> diff --git a/lib/xe/xe_sriov_debugfs.c b/lib/xe/xe_sriov_debugfs.c
> index abb1bf7d5..fb8a7c3e3 100644
> --- a/lib/xe/xe_sriov_debugfs.c
> +++ b/lib/xe/xe_sriov_debugfs.c
> @@ -471,3 +471,81 @@ DEFINE_XE_SRIOV_PF_DEBUGFS_FUNC(bool *, get_boolean, __igt_sysfs_get_boolean)
>    * Return: 0 on success, negative error code on failure.
>    */
>   DEFINE_XE_SRIOV_PF_DEBUGFS_FUNC(bool, set_boolean, __igt_sysfs_set_boolean)
> +
> +

CHECK:LINE_SPACING: Please don't use multiple blank lines


> +/**
> + * __xe_sriov_vf_debugfs_get_selfconfig - Read VF's configuration data.
> + * @vf: VF device file descriptor
> + * @res: Shared resource type (see enum xe_sriov_shared_res)
> + * @gt_num: GT number
> + * @value: Pointer to store the read value
> + *
> + * Reads the specified shared resource @res from selfconfig of given VF device
> + * @vf on GT @gt_num.
> + *
> + * Return: 0 on success, negative error code on failure.
> + */
> +int __xe_sriov_vf_debugfs_get_selfconfig(int vf, enum xe_sriov_shared_res res,
> +					    unsigned int gt_num, uint64_t *value)

CHECK:PARENTHESIS_ALIGNMENT: Alignment should match open parenthesis

> +{
> +	FILE *file;
> +	size_t n = 0;
> +	char *line = NULL;
> +	int fd, ret = 0;
> +
> +	fd = igt_debugfs_gt_open(vf, gt_num, "vf/self_config", O_RDONLY);
> +	if (fd < 0)
> +		return fd;
> +	file = fdopen(fd, "r");
> +	if (!file) {
> +		close(fd);
> +		return -errno;
> +	}
> +
> +	while (getline(&line, &n, file) >= 0) {
> +		switch (res) {
> +		case XE_SRIOV_SHARED_RES_CONTEXTS:
> +			ret = sscanf(line, "GuC contexts: %lu", value);
> +			break;
> +		case XE_SRIOV_SHARED_RES_DOORBELLS:
> +			ret = sscanf(line, "GuC doorbells: %lu", value);
> +			break;
> +		case XE_SRIOV_SHARED_RES_GGTT:
> +			ret = sscanf(line, "GGTT size: %lu", value);
> +			break;
> +		case XE_SRIOV_SHARED_RES_LMEM:
> +			ret = sscanf(line, "LMEM size: %lu", value);
> +			break;
> +		}
> +
> +		if (ret > 0)
> +			break;
> +	}
> +
> +	free(line);
> +	fclose(file);
> +
> +	return ret ? 0 : -1;
> +}
> +/**

CHECK:LINE_SPACING: Please use a blank line after 
function/struct/union/enum declarations

> + * xe_sriov_vf_debugfs_get_selfconfig - Read VF's configuration data.
> + * @pf: PF device file descriptor
> + * @res: Shared resource type (see enum xe_sriov_shared_res)
> + * @gt_num: GT number
> + *
> + * A throwing version of __xe_sriov_vf_debugfs_get_selfconfig().
> + * Instead of returning an error code, it returns the quota value and asserts
> + * in case of an error.
> + *
> + * Return: The quota for the given shared resource.
> + *         Asserts in case of failure.
> + */
> +uint64_t xe_sriov_vf_debugfs_get_selfconfig(int vf, enum xe_sriov_shared_res res,
> +					       unsigned int gt_num)

CHECK:PARENTHESIS_ALIGNMENT: Alignment should match open parenthesis

> +{
> +	uint64_t value;
> +
> +	igt_fail_on(__xe_sriov_vf_debugfs_get_selfconfig(vf, res, gt_num, &value));
> +
> +	return value;
> +}
> diff --git a/lib/xe/xe_sriov_debugfs.h b/lib/xe/xe_sriov_debugfs.h
> index cd5f932be..4983afbb3 100644
> --- a/lib/xe/xe_sriov_debugfs.h
> +++ b/lib/xe/xe_sriov_debugfs.h
> @@ -39,4 +39,9 @@ int __xe_sriov_pf_debugfs_set_boolean(int pf, unsigned int vf_num,
>   				      unsigned int gt_num, const char *attr,
>   				      bool value);
>   
> +int __xe_sriov_vf_debugfs_get_selfconfig(int vf, enum xe_sriov_shared_res res,
> +					 unsigned int gt_num, uint64_t *value);
> +uint64_t xe_sriov_vf_debugfs_get_selfconfig(int vf, enum xe_sriov_shared_res res,
> +					    unsigned int gt_num);
> +
>   #endif /* __XE_SRIOV_DEBUGFS_H__ */