Re: [igt-dev] [PATCH i-g-t 4/6] lib/kms: Add helpers for VDSC Fractional BPP debugfs entry

["Nautiyal, Ankit K" <ankit.k.nautiyal@intel.com>]

On 11/25/2022 5:28 PM, Swati Sharma wrote:
> Helper functions are added for getting/setting VDSC Fractional BPP
> debugfs entry.
>
> Signed-off-by: Swati Sharma <swati2.sharma@intel.com>
> ---
>   lib/igt_kms.c | 78 +++++++++++++++++++++++++++++++++++++++++++++++++++
>   lib/igt_kms.h |  4 +++
>   2 files changed, 82 insertions(+)
>
> diff --git a/lib/igt_kms.c b/lib/igt_kms.c
> index c7135790b..93f45410c 100644
> --- a/lib/igt_kms.c
> +++ b/lib/igt_kms.c
> @@ -5592,6 +5592,20 @@ bool check_dsc_ycbcr420_debugfs(int drmfd, char *connector_name,
>   	return strstr(buf, check_str);
>   }
>   
> +static
> +bool check_dsc_fractional_bpp_debugfs(int drmfd, char *connector_name,
> +				      const char *check_str)
> +{
> +	char file_name[128] = {0};
> +	char buf[512];
> +
> +	sprintf(file_name, "%s/i915_dsc_fractional_bpp", connector_name);
> +
> +	igt_debugfs_read(drmfd, file_name, buf);
> +
> +	return strstr(buf, check_str);
> +}
> +
>   static
>   int write_dsc_debugfs(int drmfd, char *connector_name,
>   		      const char *file_name,
> @@ -5623,6 +5637,29 @@ bool igt_is_dsc_supported(int drmfd, char *connector_name)
>   	return check_dsc_debugfs(drmfd, connector_name, "DSC_Sink_Support: yes");
>   }
>   
> +/*
> + * igt_get_dsc_fractional_bpp_supported:
> + * @drmfd: A drm file descriptor
> + * @connector_name: Name of the libdrm connector we're going to use
> + *
> + * Returns: The dsc sink bpp precision.

Perhaps need to specify precision value of 16 means 1/16, 8 means 1/8 
and so on.

A value of 1 means fractional bpp not supported.


> + */
> +int igt_get_dsc_fractional_bpp_supported(int drmfd, char *connector_name)
> +{
> +	char file_name[128] = {0};
> +	char buf[24];

This size is not sufficient to store the contents of the debugfs entry.


Thanks & Regards,

Ankit


> +	char *start_loc;
> +	int bpp_prec;
> +
> +	sprintf(file_name, "%s/i915_dsc_fec_support", connector_name);
> +	igt_debugfs_read(drmfd, file_name, buf);
> +
> +	igt_assert(start_loc = strstr(buf, "DSC_Sink_BPP_Precision: "));
> +	igt_assert_eq(sscanf(start_loc, "DSC_Sink_BPP_Precision: %d", &bpp_prec), 1);
> +
> +	return bpp_prec;
> +}
> +
>   /*
>    * igt_is_dsc_ycbcr420_supported:
>    * @drmfd: A drm file descriptor
> @@ -5685,6 +5722,19 @@ bool igt_is_force_dsc_ycbcr420_enabled(int drmfd, char *connector_name)
>   	return check_dsc_ycbcr420_debugfs(drmfd, connector_name, "Force_DSC_YCBCR420_Enable: yes");
>   }
>   
> +/*
> + * igt_is_force_dsc_fractional_bpp_enabled:
> + * @drmfd: A drm file descriptor
> + * @connector_name: Name of the libdrm connector we're going to use
> + *
> + * Returns: True if DSC Fractional BPP is force enabled (via debugfs) for the given connector,
> + * false otherwise.
> + */
> +bool igt_is_force_dsc_fractional_bpp_enabled(int drmfd, char *connector_name)
> +{
> +	return check_dsc_fractional_bpp_debugfs(drmfd, connector_name, "Force_DSC_Fractional_BPP_Enable: yes");
> +}
> +
>   /*
>    * igt_force_dsc_enable:
>    * @drmfd: A drm file descriptor
> @@ -5709,6 +5759,18 @@ int igt_force_dsc_ycbcr420_enable(int drmfd, char *connector_name)
>   	return write_dsc_debugfs(drmfd, connector_name, "i915_dsc_ycbcr420", "1");
>   }
>   
> +/*
> + * igt_force_dsc_fractional_bpp_enable:
> + * @drmfd: A drm file descriptor
> + * @connector_name: Name of the libdrm connector we're going to use
> + *
> + * Returns: 1 on success or negative error code, in case of failure.
> + */
> +int igt_force_dsc_fractional_bpp_enable(int drmfd, char *connector_name)
> +{
> +	return write_dsc_debugfs(drmfd, connector_name, "i915_dsc_fractional_bpp", "1");
> +}
> +
>   /*
>    * igt_force_dsc_enable_bpc:
>    * @drmfd: A drm file descriptor
> @@ -5758,6 +5820,22 @@ int igt_get_dsc_ycbcr420_debugfs_fd(int drmfd, char *connector_name)
>   	return openat(igt_debugfs_dir(drmfd), file_name, O_WRONLY);
>   }
>   
> +/*
> + * igt_get_dsc_fractional_bpp_debugfs_fd:
> + * @drmfd: A drm file descriptor
> + * @connector_name: Name of the libdrm connector we're going to use
> + *
> + * Returns: fd of the DSC Fractional BPP debugfs for the given connector, else returns -1.
> + */
> +int igt_get_dsc_fractional_bpp_debugfs_fd(int drmfd, char *connector_name)
> +{
> +	char file_name[128] = {0};
> +
> +	sprintf(file_name, "%s/i915_dsc_fractional_bpp", connector_name);
> +
> +	return openat(igt_debugfs_dir(drmfd), file_name, O_WRONLY);
> +}
> +
>   /*
>    * igt_get_output_max_bpc:
>    * @drmfd: A drm file descriptor
> diff --git a/lib/igt_kms.h b/lib/igt_kms.h
> index ccd8adf2c..990157bbc 100644
> --- a/lib/igt_kms.h
> +++ b/lib/igt_kms.h
> @@ -977,15 +977,19 @@ bool igt_override_all_active_output_modes_to_fit_bw(igt_display_t *display);
>   
>   bool igt_is_dsc_supported(int drmfd, char *connector_name);
>   bool igt_is_dsc_ycbcr420_supported(int drmfd, char *connector_name);
> +int igt_get_dsc_fractional_bpp_supported(int drmfd, char *connector_name);
>   bool igt_is_fec_supported(int drmfd, char *connector_name);
>   bool igt_is_dsc_enabled(int drmfd, char *connector_name);
>   bool igt_is_force_dsc_enabled(int drmfd, char *connector_name);
>   bool igt_is_force_dsc_ycbcr420_enabled(int drmfd, char *connector_name);
> +bool igt_is_force_dsc_fractional_bpp_enabled(int drmfd, char *connector_name);
>   int igt_force_dsc_enable(int drmfd, char *connector_name);
>   int igt_force_dsc_enable_bpc(int drmfd, char *connector_name, int bpc);
>   int igt_force_dsc_ycbcr420_enable(int drmfd, char *connector_name);
> +int igt_force_dsc_fractional_bpp_enable(int drmfd, char *connector_name);
>   int igt_get_dsc_debugfs_fd(int drmfd, char *connector_name);
>   int igt_get_dsc_ycbcr420_debugfs_fd(int drmfd, char *connector_name);
> +int igt_get_dsc_fractional_bpp_debugfs_fd(int drmfd, char *connector_name);
>   
>   unsigned int igt_get_output_max_bpc(int drmfd, char *connector_name);
>   unsigned int igt_get_pipe_current_bpc(int drmfd, enum pipe pipe);