/*
* Copyright © 2009 Intel Corporation
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice (including the next
* paragraph) shall be included in all copies or substantial portions of the
* Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
* IN THE SOFTWARE.
*
* Authors:
* Eric Anholt <eric@anholt.net>
*
*/
#include "brw_context.h"
#include "brw_state.h"
#include "brw_defines.h"
#include "brw_util.h"
#include "main/macros.h"
#include "main/fbobject.h"
#include "intel_batchbuffer.h"
/**
* Determine the appropriate attribute override value to store into the
* 3DSTATE_SF structure for a given fragment shader attribute. The attribute
* override value contains two pieces of information: the location of the
* attribute in the VUE (relative to urb_entry_read_offset, see below), and a
* flag indicating whether to "swizzle" the attribute based on the direction
* the triangle is facing.
*
* If an attribute is "swizzled", then the given VUE location is used for
* front-facing triangles, and the VUE location that immediately follows is
* used for back-facing triangles. We use this to implement the mapping from
* gl_FrontColor/gl_BackColor to gl_Color.
*
* urb_entry_read_offset is the offset into the VUE at which the SF unit is
* being instructed to begin reading attribute data. It can be set to a
* nonzero value to prevent the SF unit from wasting time reading elements of
* the VUE that are not needed by the fragment shader. It is measured in
* 256-bit increments.
*/
static uint32_t
get_attr_override(const struct brw_vue_map *vue_map, int urb_entry_read_offset,
int fs_attr, bool two_side_color, uint32_t *max_source_attr)
{
/* Find the VUE slot for this attribute. */
int slot = vue_map->varying_to_slot[fs_attr];
/* If there was only a back color written but not front, use back
* as the color instead of undefined
*/
if (slot == -1 && fs_attr == VARYING_SLOT_COL0)
slot = vue_map->varying_to_slot[VARYING_SLOT_BFC0];
if (slot == -1 && fs_attr == VARYING_SLOT_COL1)
slot = vue_map->varying_to_slot[VARYING_SLOT_BFC1];
if (slot == -1) {
/* This attribute does not exist in the VUE--that means that the vertex
* shader did not write to it. This means that either:
*
* (a) This attribute is a texture coordinate, and it is going to be
* replaced with point coordinates (as a consequence of a call to
* glTexEnvi(GL_POINT_SPRITE, GL_COORD_REPLACE, GL_TRUE)), so the
* hardware will ignore whatever attribute override we supply.
*
* (b) This attribute is read by the fragment shader but not written by
* the vertex shader, so its value is undefined. Therefore the
* attribute override we supply doesn't matter.
*
* (c) This attribute is gl_PrimitiveID, and it wasn't written by the
* previous shader stage.
*
* Note that we don't have to worry about the cases where the attribute
* is gl_PointCoord or is undergoing point sprite coordinate
* replacement, because in those cases, this function isn't called.
*
* In case (c), we need to program the attribute overrides so that the
* primitive ID will be stored in this slot. In every other case, the
* attribute override we supply doesn't matter. So just go ahead and
* program primitive ID in every case.
*/
return (ATTRIBUTE_0_OVERRIDE_W |
ATTRIBUTE_0_OVERRIDE_Z |
ATTRIBUTE_0_OVERRIDE_Y |
ATTRIBUTE_0_OVERRIDE_X |
(ATTRIBUTE_CONST_PRIM_ID << ATTRIBUTE_0_CONST_SOURCE_SHIFT));
}
/* Compute the location of the attribute relative to urb_entry_read_offset.
* Each increment of urb_entry_read_offset represents a 256-bit value, so
* it counts for two 128-bit VUE slots.
*/
int source_attr = slot - 2 * urb_entry_read_offset;
assert(source_attr
>= 0 && source_attr
< 32);
/* If we are doing two-sided color, and the VUE slot following this one
* represents a back-facing color, then we need to instruct the SF unit to
* do back-facing swizzling.
*/
bool swizzling = two_side_color &&
((vue_map->slot_to_varying[slot] == VARYING_SLOT_COL0 &&
vue_map->slot_to_varying[slot+1] == VARYING_SLOT_BFC0) ||
(vue_map->slot_to_varying[slot] == VARYING_SLOT_COL1 &&
vue_map->slot_to_varying[slot+1] == VARYING_SLOT_BFC1));
/* Update max_source_attr. If swizzling, the SF will read this slot + 1. */
if (*max_source_attr < source_attr + swizzling)
*max_source_attr = source_attr + swizzling;
if (swizzling) {
return source_attr |
(ATTRIBUTE_SWIZZLE_INPUTATTR_FACING << ATTRIBUTE_SWIZZLE_SHIFT);
}
return source_attr;
}
static bool
is_drawing_points(const struct brw_context *brw)
{
/* Determine if the primitives *reaching the SF* are points */
/* _NEW_POLYGON */
if (brw->ctx.Polygon.FrontMode == GL_POINT ||
brw->ctx.Polygon.BackMode == GL_POINT) {
return true;
}
if (brw->geometry_program) {
/* BRW_NEW_GEOMETRY_PROGRAM */
return brw->geometry_program->OutputType == GL_POINTS;
} else {
/* BRW_NEW_PRIMITIVE */
return brw->primitive == _3DPRIM_POINTLIST;
}
}
/**
* Create the mapping from the FS inputs we produce to the previous pipeline
* stage (GS or VS) outputs they source from.
*/
void
calculate_attr_overrides(const struct brw_context *brw,
uint16_t *attr_overrides,
uint32_t *point_sprite_enables,
uint32_t *flat_enables,
uint32_t *urb_entry_read_length)
{
const int urb_entry_read_offset = BRW_SF_URB_ENTRY_READ_OFFSET;
uint32_t max_source_attr = 0;
*point_sprite_enables = 0;
*flat_enables = 0;
/* _NEW_LIGHT */
bool shade_model_flat = brw->ctx.Light.ShadeModel == GL_FLAT;
/* From the Ivybridge PRM, Vol 2 Part 1, 3DSTATE_SBE,
* description of dw10 Point Sprite Texture Coordinate Enable:
*
* "This field must be programmed to zero when non-point primitives
* are rendered."
*
* The SandyBridge PRM doesn't explicitly say that point sprite enables
* must be programmed to zero when rendering non-point primitives, but
* the IvyBridge PRM does, and if we don't, we get garbage.
*
* This is not required on Haswell, as the hardware ignores this state
* when drawing non-points -- although we do still need to be careful to
* correctly set the attr overrides.
*/
/* BRW_NEW_PRIMITIVE | BRW_NEW_GEOMETRY_PROGRAM */
bool drawing_points = is_drawing_points(brw);
/* Initialize all the attr_overrides to 0. In the loop below we'll modify
* just the ones that correspond to inputs used by the fs.
*/
memset(attr_overrides
, 0, 16*sizeof(*attr_overrides
));
for (int attr = 0; attr < VARYING_SLOT_MAX; attr++) {
/* BRW_NEW_FRAGMENT_PROGRAM */
enum glsl_interp_qualifier interp_qualifier =
brw->fragment_program->InterpQualifier[attr];
bool is_gl_Color = attr == VARYING_SLOT_COL0 || attr == VARYING_SLOT_COL1;
/* BRW_NEW_FS_PROG_DATA */
int input_index = brw->wm.prog_data->urb_setup[attr];
if (input_index < 0)
continue;
/* _NEW_POINT */
bool point_sprite = false;
if (drawing_points) {
if (brw->ctx.Point.PointSprite &&
(attr >= VARYING_SLOT_TEX0 && attr <= VARYING_SLOT_TEX7) &&
brw->ctx.Point.CoordReplace[attr - VARYING_SLOT_TEX0]) {
point_sprite = true;
}
if (attr == VARYING_SLOT_PNTC)
point_sprite = true;
if (point_sprite)
*point_sprite_enables |= (1 << input_index);
}
/* flat shading */
if (interp_qualifier == INTERP_QUALIFIER_FLAT ||
(shade_model_flat && is_gl_Color &&
interp_qualifier == INTERP_QUALIFIER_NONE))
*flat_enables |= (1 << input_index);
/* BRW_NEW_VUE_MAP_GEOM_OUT | _NEW_LIGHT | _NEW_PROGRAM */
uint16_t attr_override = point_sprite ? 0 :
get_attr_override(&brw->vue_map_geom_out,
urb_entry_read_offset, attr,
brw->ctx.VertexProgram._TwoSideEnabled,
&max_source_attr);
/* The hardware can only do the overrides on 16 overrides at a
* time, and the other up to 16 have to be lined up so that the
* input index = the output index. We'll need to do some
* tweaking to make sure that's the case.
*/
if (input_index < 16)
attr_overrides[input_index] = attr_override;
else
assert(attr_override
== input_index
); }
/* From the Sandy Bridge PRM, Volume 2, Part 1, documentation for
* 3DSTATE_SF DWord 1 bits 15:11, "Vertex URB Entry Read Length":
*
* "This field should be set to the minimum length required to read the
* maximum source attribute. The maximum source attribute is indicated
* by the maximum value of the enabled Attribute # Source Attribute if
* Attribute Swizzle Enable is set, Number of Output Attributes-1 if
* enable is not set.
* read_length = ceiling((max_source_attr + 1) / 2)
*
* [errata] Corruption/Hang possible if length programmed larger than
* recommended"
*
* Similar text exists for Ivy Bridge.
*/
*urb_entry_read_length = ALIGN(max_source_attr + 1, 2) / 2;
}
static void
upload_sf_state(struct brw_context *brw)
{
struct gl_context *ctx = &brw->ctx;
/* BRW_NEW_FS_PROG_DATA */
uint32_t num_outputs = brw->wm.prog_data->num_varying_inputs;
uint32_t dw1, dw2, dw3, dw4;
uint32_t point_sprite_enables;
uint32_t flat_enables;
int i;
/* _NEW_BUFFER */
bool render_to_fbo = _mesa_is_user_fbo(ctx->DrawBuffer);
bool multisampled_fbo = ctx->DrawBuffer->Visual.samples > 1;
const int urb_entry_read_offset = BRW_SF_URB_ENTRY_READ_OFFSET;
float point_size;
uint16_t attr_overrides[16];
uint32_t point_sprite_origin;
dw1 = GEN6_SF_SWIZZLE_ENABLE | num_outputs << GEN6_SF_NUM_OUTPUTS_SHIFT;
dw2 = GEN6_SF_STATISTICS_ENABLE;
if (brw->sf.viewport_transform_enable)
dw2 |= GEN6_SF_VIEWPORT_TRANSFORM_ENABLE;
dw3 = 0;
dw4 = 0;
/* _NEW_POLYGON */
if (ctx->Polygon._FrontBit == render_to_fbo)
dw2 |= GEN6_SF_WINDING_CCW;
if (ctx->Polygon.OffsetFill)
dw2 |= GEN6_SF_GLOBAL_DEPTH_OFFSET_SOLID;
if (ctx->Polygon.OffsetLine)
dw2 |= GEN6_SF_GLOBAL_DEPTH_OFFSET_WIREFRAME;
if (ctx->Polygon.OffsetPoint)
dw2 |= GEN6_SF_GLOBAL_DEPTH_OFFSET_POINT;
switch (ctx->Polygon.FrontMode) {
case GL_FILL:
dw2 |= GEN6_SF_FRONT_SOLID;
break;
case GL_LINE:
dw2 |= GEN6_SF_FRONT_WIREFRAME;
break;
case GL_POINT:
dw2 |= GEN6_SF_FRONT_POINT;
break;
default:
unreachable("not reached");
}
switch (ctx->Polygon.BackMode) {
case GL_FILL:
dw2 |= GEN6_SF_BACK_SOLID;
break;
case GL_LINE:
dw2 |= GEN6_SF_BACK_WIREFRAME;
break;
case GL_POINT:
dw2 |= GEN6_SF_BACK_POINT;
break;
default:
unreachable("not reached");
}
/* _NEW_SCISSOR */
if (ctx->Scissor.EnableFlags)
dw3 |= GEN6_SF_SCISSOR_ENABLE;
/* _NEW_POLYGON */
if (ctx->Polygon.CullFlag) {
switch (ctx->Polygon.CullFaceMode) {
case GL_FRONT:
dw3 |= GEN6_SF_CULL_FRONT;
break;
case GL_BACK:
dw3 |= GEN6_SF_CULL_BACK;
break;
case GL_FRONT_AND_BACK:
dw3 |= GEN6_SF_CULL_BOTH;
break;
default:
unreachable("not reached");
}
} else {
dw3 |= GEN6_SF_CULL_NONE;
}
/* _NEW_LINE */
{
/* OpenGL dictates that line width should be rounded to the nearest
* integer
*/
float line_width =
roundf(CLAMP(ctx->Line.Width, 0.0, ctx->Const.MaxLineWidth));
uint32_t line_width_u3_7 = U_FIXED(line_width, 7);
/* Line width of 0 is not allowed when MSAA enabled */
if (ctx->Multisample._Enabled) {
if (line_width_u3_7 == 0)
line_width_u3_7 = 1;
} else if (ctx->Line.SmoothFlag && ctx->Line.Width < 1.5) {
/* For 1 pixel line thickness or less, the general
* anti-aliasing algorithm gives up, and a garbage line is
* generated. Setting a Line Width of 0.0 specifies the
* rasterization of the "thinnest" (one-pixel-wide),
* non-antialiased lines.
*
* Lines rendered with zero Line Width are rasterized using
* Grid Intersection Quantization rules as specified by
* bspec section 6.3.12.1 Zero-Width (Cosmetic) Line
* Rasterization.
*/
line_width_u3_7 = 0;
}
dw3 |= line_width_u3_7 << GEN6_SF_LINE_WIDTH_SHIFT;
}
if (ctx->Line.SmoothFlag) {
dw3 |= GEN6_SF_LINE_AA_ENABLE;
dw3 |= GEN6_SF_LINE_AA_MODE_TRUE;
dw3 |= GEN6_SF_LINE_END_CAP_WIDTH_1_0;
}
/* _NEW_MULTISAMPLE */
if (multisampled_fbo && ctx->Multisample.Enabled)
dw3 |= GEN6_SF_MSRAST_ON_PATTERN;
/* _NEW_PROGRAM | _NEW_POINT */
if (!(ctx->VertexProgram.PointSizeEnabled ||
ctx->Point._Attenuated))
dw4 |= GEN6_SF_USE_STATE_POINT_WIDTH;
/* Clamp to ARB_point_parameters user limits */
point_size = CLAMP(ctx->Point.Size, ctx->Point.MinSize, ctx->Point.MaxSize);
/* Clamp to the hardware limits and convert to fixed point */
dw4 |= U_FIXED(CLAMP(point_size, 0.125, 255.875), 3);
/*
* Window coordinates in an FBO are inverted, which means point
* sprite origin must be inverted, too.
*/
if ((ctx->Point.SpriteOrigin == GL_LOWER_LEFT) != render_to_fbo) {
point_sprite_origin = GEN6_SF_POINT_SPRITE_LOWERLEFT;
} else {
point_sprite_origin = GEN6_SF_POINT_SPRITE_UPPERLEFT;
}
dw1 |= point_sprite_origin;
/* _NEW_LIGHT */
if (ctx->Light.ProvokingVertex != GL_FIRST_VERTEX_CONVENTION) {
dw4 |=
(2 << GEN6_SF_TRI_PROVOKE_SHIFT) |
(2 << GEN6_SF_TRIFAN_PROVOKE_SHIFT) |
(1 << GEN6_SF_LINE_PROVOKE_SHIFT);
} else {
dw4 |=
(1 << GEN6_SF_TRIFAN_PROVOKE_SHIFT);
}
/* BRW_NEW_VUE_MAP_GEOM_OUT | BRW_NEW_FRAGMENT_PROGRAM |
* _NEW_POINT | _NEW_LIGHT | _NEW_PROGRAM | BRW_NEW_FS_PROG_DATA
*/
uint32_t urb_entry_read_length;
calculate_attr_overrides(brw, attr_overrides, &point_sprite_enables,
&flat_enables, &urb_entry_read_length);
dw1 |= (urb_entry_read_length << GEN6_SF_URB_ENTRY_READ_LENGTH_SHIFT |
urb_entry_read_offset << GEN6_SF_URB_ENTRY_READ_OFFSET_SHIFT);
BEGIN_BATCH(20);
OUT_BATCH(_3DSTATE_SF << 16 | (20 - 2));
OUT_BATCH(dw1);
OUT_BATCH(dw2);
OUT_BATCH(dw3);
OUT_BATCH(dw4);
OUT_BATCH_F(ctx->Polygon.OffsetUnits * 2); /* constant. copied from gen4 */
OUT_BATCH_F(ctx->Polygon.OffsetFactor); /* scale */
OUT_BATCH_F(ctx->Polygon.OffsetClamp); /* global depth offset clamp */
for (i = 0; i < 8; i++) {
OUT_BATCH(attr_overrides[i * 2] | attr_overrides[i * 2 + 1] << 16);
}
OUT_BATCH(point_sprite_enables); /* dw16 */
OUT_BATCH(flat_enables);
OUT_BATCH(0); /* wrapshortest enables 0-7 */
OUT_BATCH(0); /* wrapshortest enables 8-15 */
ADVANCE_BATCH();
}
const struct brw_tracked_state gen6_sf_state = {
.dirty = {
.mesa = _NEW_BUFFERS |
_NEW_LIGHT |
_NEW_LINE |
_NEW_MULTISAMPLE |
_NEW_POINT |
_NEW_POLYGON |
_NEW_PROGRAM |
_NEW_SCISSOR,
.brw = BRW_NEW_CONTEXT |
BRW_NEW_FRAGMENT_PROGRAM |
BRW_NEW_FS_PROG_DATA |
BRW_NEW_GEOMETRY_PROGRAM |
BRW_NEW_PRIMITIVE |
BRW_NEW_VUE_MAP_GEOM_OUT,
},
.emit = upload_sf_state,
};