i915g: implement hw clear

Benefits:
- spares us a relocation.
- needed for zone rendering (if that ever happens).
- just awesome.

v2: Rename the debug option. Completely disabling the blitter is
required for Y tiling to work, so this option will cover other
code paths in the future.

v3: Implement suggestions by Jakob Bornecrantz.

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

1 files changed, 103 insertions, 2 deletions

diff --git a/src/gallium/drivers/i915/i915_clear.c b/src/gallium/drivers/i915/i915_clear.c
index 6d824a507a..b5d6d8a01a 100644
--- a/src/gallium/drivers/i915/i915_clear.c
+++ b/src/gallium/drivers/i915/i915_clear.c
@@ -31,17 +31,118 @@
 
 
 #include "util/u_clear.h"
+#include "util/u_format.h"
+#include "util/u_pack_color.h"
 #include "i915_context.h"
+#include "i915_screen.h"
+#include "i915_reg.h"
+#include "i915_batch.h"
+#include "i915_resource.h"
+#include "i915_state.h"
 
+static void
+i915_clear_emit(struct pipe_context *pipe, unsigned buffers, const float *rgba,
+                double depth, unsigned stencil,
+                unsigned destx, unsigned desty, unsigned width, unsigned height)
+{
+   struct i915_context *i915 = i915_context(pipe);
+   uint32_t clear_params, clear_color, clear_depth, clear_stencil,
+            clear_color8888, packed_z_stencil;
+   union util_color u_color;
+   float f_depth = depth;
+   struct i915_texture *cbuf_tex, *depth_tex;
+
+   cbuf_tex = depth_tex = NULL;
+   clear_params = 0;
+
+   if (buffers & PIPE_CLEAR_COLOR) {
+      struct pipe_surface *cbuf = i915->framebuffer.cbufs[0];
+
+      clear_params |= CLEARPARAM_WRITE_COLOR;
+      cbuf_tex = i915_texture(cbuf->texture);
+      util_pack_color(rgba, cbuf->format, &u_color);
+      if (util_format_get_blocksize(cbuf_tex->b.b.format) == 4)
+         clear_color = u_color.ui;
+      else
+         clear_color = (u_color.ui & 0xffff) | (u_color.ui << 16);
+
+      util_pack_color(rgba, PIPE_FORMAT_B8G8R8A8_UNORM, &u_color);
+      clear_color8888 = u_color.ui;
+   } else
+      clear_color = clear_color8888 = 0;
+
+   clear_depth = clear_stencil = 0;
+   if (buffers & PIPE_CLEAR_DEPTH) {
+      struct pipe_surface *zbuf = i915->framebuffer.zsbuf;
+
+      clear_params |= CLEARPARAM_WRITE_DEPTH;
+      depth_tex = i915_texture(zbuf->texture);
+      packed_z_stencil = util_pack_z_stencil(depth_tex->b.b.format, depth, stencil);
+
+      if (util_format_get_blocksize(depth_tex->b.b.format) == 4) {
+         /* Avoid read-modify-write if there's no stencil. */
+         if (buffers & PIPE_CLEAR_STENCIL
+               || depth_tex->b.b.format != PIPE_FORMAT_Z24_UNORM_S8_USCALED) {
+            clear_params |= CLEARPARAM_WRITE_STENCIL;
+            clear_stencil = packed_z_stencil & 0xff;
+            clear_depth = packed_z_stencil;
+         } else
+            clear_depth = packed_z_stencil & 0xffffff00;
+      } else {
+         clear_depth = (clear_depth & 0xffff) | (clear_depth << 16);
+      }
+   }
+
+   if (i915->hardware_dirty)
+      i915_emit_hardware_state(i915);
+
+   if (!BEGIN_BATCH(7 + 7)) {
+      FLUSH_BATCH(NULL);
+
+      i915_emit_hardware_state(i915);
+      i915->vbo_flushed = 1;
+
+      assert(BEGIN_BATCH(7 + 7));
+   }
+
+   OUT_BATCH(_3DSTATE_CLEAR_PARAMETERS);
+   OUT_BATCH(clear_params | CLEARPARAM_CLEAR_RECT);
+   OUT_BATCH(clear_color);
+   OUT_BATCH(clear_depth);
+   OUT_BATCH(clear_color8888);
+   OUT_BATCH_F(f_depth);
+   OUT_BATCH(clear_stencil);
+
+   OUT_BATCH(_3DPRIMITIVE | PRIM3D_CLEAR_RECT | 5);
+   OUT_BATCH_F(destx + width);
+   OUT_BATCH_F(desty + height);
+   OUT_BATCH_F(destx);
+   OUT_BATCH_F(desty + height);
+   OUT_BATCH_F(destx);
+   OUT_BATCH_F(desty);
+}
 
 /**
  * Clear the given buffers to the specified values.
  * No masking, no scissor (clear entire buffer).
  */
 void
-i915_clear(struct pipe_context *pipe, unsigned buffers, const float *rgba,
-           double depth, unsigned stencil)
+i915_clear_blitter(struct pipe_context *pipe, unsigned buffers, const float *rgba,
+                   double depth, unsigned stencil)
 {
    util_clear(pipe, &i915_context(pipe)->framebuffer, buffers, rgba, depth,
               stencil);
 }
+
+void
+i915_clear_render(struct pipe_context *pipe, unsigned buffers, const float *rgba,
+                  double depth, unsigned stencil)
+{
+   struct i915_context *i915 = i915_context(pipe);
+
+   if (i915->dirty)
+      i915_update_derived(i915);
+
+   i915_clear_emit(pipe, buffers, rgba, depth, stencil,
+                   0, 0, i915->current.fb_width, i915->current.fb_height);
+}