The GPU needs all the active (non-null) render targets in a
contiguous representation. For instance, if fb->nr_cbufs is 4 but
fb->cbufs[0] and fb->cbufs[1] are null we need to program the GPU that
fb->cbufs[2] is configured via PE_COLOR_FORMAT and friends and
fb->cbufs[3] via PE_RT_CONFIG[0] and friends.
We need to keep track which render target is used as we need to update
the fragment shader output mapping.
Signed-off-by: Christian Gmeiner <cgmeiner@igalia.com>
Reviewed-by: Lucas Stach <l.stach@pengutronix.de>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/26565>
Christian Gmeiner
2436babbd2