Re: [PATCH 3/4] drm/imx: add FB modifier support

Hi Lucas,

On 3 May 2017 at 17:28, Lucas Stach l.stach@pengutronix.de wrote:

    int available_pres = ipu_prg_max_active_channels();
    int i;

•   /*
  

•    * We are going over the planes in 2 passes: first we assign PREs to
  

•    * planes with a tiling modifier, which need the PREs to resolve into
  

•    * linear. Any failure to assign a PRE there is fatal. In the second
  

•    * pass we try to assign PREs to linear FBs, to improve memory access
  

•    * patterns for them. Failure at this point is non-fatal, as we can
  

•    * scan out linear FBs without a PRE.
  

•    */
    for_each_plane_in_state(state, plane, plane_state, i) {
  

•           struct ipu_plane_state *ipu_state =
  

•                           to_ipu_plane_state(plane_state);
  

•           struct ipu_plane *ipu_plane = to_ipu_plane(plane);
  

•           ipu_state = to_ipu_plane_state(plane_state);
  

•           ipu_plane = to_ipu_plane(plane);
  

•           if (!plane_state->fb) {
  

•                   ipu_state->use_pre = false;
  

•                   continue;
  

•           }
  

•           if (!(plane_state->fb->flags & DRM_MODE_FB_MODIFIERS) ||
  

•               plane_state->fb->modifier == DRM_FORMAT_MOD_LINEAR)
  

•                   continue;
  

•           if (!ipu_prg_present(ipu_plane->ipu) || !available_pres)
  

•                   return -EINVAL;
  

What about planes which aren't present in this commit, but are still taking up a PRE unit? Will they have their PRE stolen, or am I missing something?

Cheers, Daniel