etnaviv: SINGLE_BUFFER support on GC3000

This patch adds support for the SINGLE_BUFFER feature on GC3000
GPUs, which allows rendering to a single buffer using multiple pixel
pipes.

This feature is always used when it is available, which means that
multi-tiled formats are no longer being used in that case, and all
buffers will be normal (super)tiled. This mimics the behavior of the
blob on GC3000.

- Because the same format can be used to render to and texture from,
  this avoids an extra resolve pass when rendering to texture.

- i.MX6qp includes a PRE which can scan-out directly from tiled formats,
  avoiding untiling overhead.

Signed-off-by: Wladimir J. van der Laan <[email protected]>
Reviewed-by: Christian Gmeiner <[email protected]>

1 files changed, 3 insertions, 0 deletions

diff --git a/src/gallium/drivers/etnaviv/etnaviv_context.c b/src/gallium/drivers/etnaviv/etnaviv_context.c
index 555aa127651..f2f709cbf24 100644
--- a/src/gallium/drivers/etnaviv/etnaviv_context.c
+++ b/src/gallium/drivers/etnaviv/etnaviv_context.c
@@ -293,6 +293,9 @@ etna_cmd_stream_reset_notify(struct etna_cmd_stream *stream, void *priv)
    etna_set_state(stream, VIVS_RA_EARLY_DEPTH, 0x00000031);
    etna_set_state(stream, VIVS_PA_W_CLIP_LIMIT, 0x34000001);
 
+   /* Enable SINGLE_BUFFER for resolve, if supported */
+   etna_set_state(stream, VIVS_RS_SINGLE_BUFFER, COND(ctx->specs.single_buffer, VIVS_RS_SINGLE_BUFFER_ENABLE));
+
    ctx->dirty = ~0L;
 
    /* go through all the used resources and clear their status flag */