This will eventually allow us to re-use old values without
re-calculating them for unchanged planes (which also helps us avoid
re-grabbing extra plane states).
v2:
 -  Drop unnecessary memset's; they were meant for a later patch (which
    got reworked anyway to not need them, but were mis-rebased into this
    one.  (Maarten)
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1463061971-19638-6-git-send-email-matthew.d.roper@intel.com
                        /* cached plane data rate */
                        unsigned plane_data_rate[I915_MAX_PLANES];
                        unsigned plane_y_data_rate[I915_MAX_PLANES];
+
+                       /* minimum block allocation */
+                       uint16_t minimum_blocks[I915_MAX_PLANES];
+                       uint16_t minimum_y_blocks[I915_MAX_PLANES];
                } skl;
        };
 
 
        enum pipe pipe = intel_crtc->pipe;
        struct skl_ddb_entry *alloc = &ddb->pipe[pipe];
        uint16_t alloc_size, start, cursor_blocks;
-       uint16_t minimum[I915_MAX_PLANES];
-       uint16_t y_minimum[I915_MAX_PLANES];
+       uint16_t *minimum = cstate->wm.skl.minimum_blocks;
+       uint16_t *y_minimum = cstate->wm.skl.minimum_y_blocks;
        unsigned int total_data_rate;
 
        skl_ddb_get_pipe_allocation_limits(dev, cstate, config, alloc);