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authorFrancisco Jerez <[email protected]>2016-07-21 20:25:28 -0700
committerFrancisco Jerez <[email protected]>2016-08-25 18:36:06 -0700
commitaf0cc743e607293146861518bb6ef96f411aeca9 (patch)
tree8935fa3c3b305649d96637d5ad1d808f0652c9f5 /src
parentfe6abb5755e0368c993e6f7cf25a0712ee6503a9 (diff)
i965/fs: Implement non-coherent framebuffer fetch using the sampler unit.
v2: Memoize sample ID, misc codestyle changes. (Ken) Reviewed-by: Kenneth Graunke <[email protected]>
Diffstat (limited to 'src')
-rw-r--r--src/mesa/drivers/dri/i965/brw_fs.h2
-rw-r--r--src/mesa/drivers/dri/i965/brw_fs_nir.cpp92
2 files changed, 94 insertions, 0 deletions
diff --git a/src/mesa/drivers/dri/i965/brw_fs.h b/src/mesa/drivers/dri/i965/brw_fs.h
index 86e85db24ab..7819f1ca3c0 100644
--- a/src/mesa/drivers/dri/i965/brw_fs.h
+++ b/src/mesa/drivers/dri/i965/brw_fs.h
@@ -244,6 +244,8 @@ public:
fs_reg color1, fs_reg color2,
fs_reg src0_alpha, unsigned components);
void emit_fb_writes();
+ fs_inst *emit_non_coherent_fb_read(const brw::fs_builder &bld,
+ const fs_reg &dst, unsigned target);
void emit_urb_writes(const fs_reg &gs_vertex_count = fs_reg());
void set_gs_stream_control_data_bits(const fs_reg &vertex_count,
unsigned stream_id);
diff --git a/src/mesa/drivers/dri/i965/brw_fs_nir.cpp b/src/mesa/drivers/dri/i965/brw_fs_nir.cpp
index d01c4b08052..e63ea24b2fd 100644
--- a/src/mesa/drivers/dri/i965/brw_fs_nir.cpp
+++ b/src/mesa/drivers/dri/i965/brw_fs_nir.cpp
@@ -3155,6 +3155,98 @@ fs_visitor::nir_emit_gs_intrinsic(const fs_builder &bld,
}
}
+/**
+ * Fetch the current render target layer index.
+ */
+static fs_reg
+fetch_render_target_array_index(const fs_builder &bld)
+{
+ if (bld.shader->devinfo->gen >= 6) {
+ /* The render target array index is provided in the thread payload as
+ * bits 26:16 of r0.0.
+ */
+ const fs_reg idx = bld.vgrf(BRW_REGISTER_TYPE_UD);
+ bld.AND(idx, brw_uw1_reg(BRW_GENERAL_REGISTER_FILE, 0, 1),
+ brw_imm_uw(0x7ff));
+ return idx;
+ } else {
+ /* Pre-SNB we only ever render into the first layer of the framebuffer
+ * since layered rendering is not implemented.
+ */
+ return brw_imm_ud(0);
+ }
+}
+
+/**
+ * Fake non-coherent framebuffer read implemented using TXF to fetch from the
+ * framebuffer at the current fragment coordinates and sample index.
+ */
+fs_inst *
+fs_visitor::emit_non_coherent_fb_read(const fs_builder &bld, const fs_reg &dst,
+ unsigned target)
+{
+ const struct brw_device_info *devinfo = bld.shader->devinfo;
+
+ assert(bld.shader->stage == MESA_SHADER_FRAGMENT);
+ const brw_wm_prog_key *wm_key =
+ reinterpret_cast<const brw_wm_prog_key *>(key);
+ assert(!wm_key->coherent_fb_fetch);
+ const brw_wm_prog_data *wm_prog_data =
+ reinterpret_cast<const brw_wm_prog_data *>(stage_prog_data);
+
+ /* Calculate the surface index relative to the start of the texture binding
+ * table block, since that's what the texturing messages expect.
+ */
+ const unsigned surface = target +
+ wm_prog_data->binding_table.render_target_read_start -
+ wm_prog_data->base.binding_table.texture_start;
+
+ brw_mark_surface_used(
+ bld.shader->stage_prog_data,
+ wm_prog_data->binding_table.render_target_read_start + target);
+
+ /* Calculate the fragment coordinates. */
+ const fs_reg coords = bld.vgrf(BRW_REGISTER_TYPE_UD, 3);
+ bld.MOV(offset(coords, bld, 0), pixel_x);
+ bld.MOV(offset(coords, bld, 1), pixel_y);
+ bld.MOV(offset(coords, bld, 2), fetch_render_target_array_index(bld));
+
+ /* Calculate the sample index and MCS payload when multisampling. Luckily
+ * the MCS fetch message behaves deterministically for UMS surfaces, so it
+ * shouldn't be necessary to recompile based on whether the framebuffer is
+ * CMS or UMS.
+ */
+ if (wm_key->multisample_fbo &&
+ nir_system_values[SYSTEM_VALUE_SAMPLE_ID].file == BAD_FILE)
+ nir_system_values[SYSTEM_VALUE_SAMPLE_ID] = *emit_sampleid_setup();
+
+ const fs_reg sample = nir_system_values[SYSTEM_VALUE_SAMPLE_ID];
+ const fs_reg mcs = wm_key->multisample_fbo ?
+ emit_mcs_fetch(coords, 3, brw_imm_ud(surface)) : fs_reg();
+
+ /* Use either a normal or a CMS texel fetch message depending on whether
+ * the framebuffer is single or multisample. On SKL+ use the wide CMS
+ * message just in case the framebuffer uses 16x multisampling, it should
+ * be equivalent to the normal CMS fetch for lower multisampling modes.
+ */
+ const opcode op = !wm_key->multisample_fbo ? SHADER_OPCODE_TXF_LOGICAL :
+ devinfo->gen >= 9 ? SHADER_OPCODE_TXF_CMS_W_LOGICAL :
+ SHADER_OPCODE_TXF_CMS_LOGICAL;
+
+ /* Emit the instruction. */
+ const fs_reg srcs[] = { coords, fs_reg(), brw_imm_ud(0), fs_reg(),
+ sample, mcs,
+ brw_imm_ud(surface), brw_imm_ud(0),
+ fs_reg(), brw_imm_ud(3), brw_imm_ud(0) };
+ STATIC_ASSERT(ARRAY_SIZE(srcs) == TEX_LOGICAL_NUM_SRCS);
+
+ fs_inst *inst = bld.emit(op, dst, srcs, ARRAY_SIZE(srcs));
+ inst->regs_written = 4 * inst->dst.component_size(inst->exec_size) /
+ REG_SIZE;
+
+ return inst;
+}
+
void
fs_visitor::nir_emit_fs_intrinsic(const fs_builder &bld,
nir_intrinsic_instr *instr)