[PATCH v3 14/17] drm/amd/display: Add debugfs for testing output colorspace

[Sebastian Wick]

On Tue, Mar 7, 2023 at 4:12 PM Harry Wentland <harry.wentland at amd.com> wrote:
>
> In order to IGT test colorspace we'll want to print
> the currently enabled colorspace on a stream. We add
> a new debugfs to do so, using the same scheme as
> current bpc reporting.
>
> This might also come in handy when debugging display
> issues.
>
> Signed-off-by: Harry Wentland <harry.wentland at amd.com>
> Cc: Pekka Paalanen <ppaalanen at gmail.com>
> Cc: Sebastian Wick <sebastian.wick at redhat.com>
> Cc: Vitaly.Prosyak at amd.com
> Cc: Joshua Ashton <joshua at froggi.es>
> Cc: dri-devel at lists.freedesktop.org
> Cc: amd-gfx at lists.freedesktop.org
> Reviewed-By: Joshua Ashton <joshua at froggi.es>
> ---
>  .../amd/display/amdgpu_dm/amdgpu_dm_debugfs.c | 57 +++++++++++++++++++
>  1 file changed, 57 insertions(+)
>
> diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_debugfs.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_debugfs.c
> index 4a5dae578d97..f0022c16b708 100644
> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_debugfs.c
> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_debugfs.c
> @@ -906,6 +906,61 @@ static int amdgpu_current_bpc_show(struct seq_file *m, void *data)
>  }
>  DEFINE_SHOW_ATTRIBUTE(amdgpu_current_bpc);
>
> +/*
> + * Returns the current bpc for the crtc.
> + * Example usage: cat /sys/kernel/debug/dri/0/crtc-0/amdgpu_current_colorspace
> + */
> +static int amdgpu_current_colorspace_show(struct seq_file *m, void *data)
> +{
> +       struct drm_crtc *crtc = m->private;
> +       struct drm_device *dev = crtc->dev;
> +       struct dm_crtc_state *dm_crtc_state = NULL;
> +       int res = -ENODEV;
> +
> +       mutex_lock(&dev->mode_config.mutex);
> +       drm_modeset_lock(&crtc->mutex, NULL);
> +       if (crtc->state == NULL)
> +               goto unlock;
> +
> +       dm_crtc_state = to_dm_crtc_state(crtc->state);
> +       if (dm_crtc_state->stream == NULL)
> +               goto unlock;
> +
> +       switch (dm_crtc_state->stream->output_color_space) {
> +       case COLOR_SPACE_SRGB:
> +               seq_printf(m, "RGB");
> +               break;

Why does it print "RGB" when it says the color space is sRGB? Looking
at the value when I didn't specify any color space it says RGB. Why is
your default color space sRGB?


> +       case COLOR_SPACE_YCBCR601:
> +       case COLOR_SPACE_YCBCR601_LIMITED:
> +               seq_printf(m, "BT601_YCC");
> +               break;
> +       case COLOR_SPACE_YCBCR709:
> +       case COLOR_SPACE_YCBCR709_LIMITED:
> +               seq_printf(m, "BT709_YCC");
> +               break;
> +       case COLOR_SPACE_ADOBERGB:
> +               seq_printf(m, "opRGB");
> +               break;
> +       case COLOR_SPACE_2020_RGB_FULLRANGE:
> +               seq_printf(m, "BT2020_RGB");
> +               break;
> +       case COLOR_SPACE_2020_YCBCR:
> +               seq_printf(m, "BT2020_YCC");
> +               break;
> +       default:
> +               goto unlock;
> +       }
> +       res = 0;
> +
> +unlock:
> +       drm_modeset_unlock(&crtc->mutex);
> +       mutex_unlock(&dev->mode_config.mutex);
> +
> +       return res;
> +}
> +DEFINE_SHOW_ATTRIBUTE(amdgpu_current_colorspace);
> +
> +
>  /*
>   * Example usage:
>   * Disable dsc passthrough, i.e.,: have dsc decoding at converver, not external RX
> @@ -3235,6 +3290,8 @@ void crtc_debugfs_init(struct drm_crtc *crtc)
>  #endif
>         debugfs_create_file("amdgpu_current_bpc", 0644, crtc->debugfs_entry,
>                             crtc, &amdgpu_current_bpc_fops);
> +       debugfs_create_file("amdgpu_current_colorspace", 0644, crtc->debugfs_entry,
> +                           crtc, &amdgpu_current_colorspace_fops);
>  }
>
>  /*
> --
> 2.39.2
>