* Keith Whitwell <keithw@vmware.com>
*/
+/** @file brw_curbe.c
+ *
+ * Push constant handling for gen4/5.
+ *
+ * Push constants are constant values (such as GLSL uniforms) that are
+ * pre-loaded into a shader stage's register space at thread spawn time. On
+ * gen4 and gen5, we create a blob in memory containing all the push constants
+ * for all the stages in order. At CMD_CONST_BUFFER time that blob is loaded
+ * into URB space as a constant URB entry (CURBE) so that it can be accessed
+ * quickly at thread setup time. Each individual fixed function unit's state
+ * (brw_vs_state.c for example) tells the hardware which subset of the CURBE
+ * it wants in its register space, and we calculate those areas here under the
+ * BRW_NEW_PUSH_CONSTANT_ALLOCATION state flag. The brw_urb.c allocation will control
+ * how many CURBEs can be loaded into the hardware at once before a pipeline
+ * stall occurs at CMD_CONST_BUFFER time.
+ *
+ * On gen6+, constant handling becomes a much simpler set of per-unit state.
+ * See gen6_upload_vec4_push_constants() in gen6_vs_state.c for that code.
+ */
-#include "main/glheader.h"
+#include "compiler/nir/nir.h"
#include "main/context.h"
#include "main/macros.h"
#include "main/enums.h"
#include "program/prog_parameter.h"
#include "program/prog_print.h"
#include "program/prog_statevars.h"
+#include "util/bitscan.h"
#include "intel_batchbuffer.h"
#include "intel_buffer_objects.h"
#include "brw_context.h"
/**
- * Partition the CURBE between the various users of constant values:
- * Note that vertex and fragment shaders can now fetch constants out
- * of constant buffers. We no longer allocatea block of the GRF for
- * constants. That greatly reduces the demand for space in the CURBE.
- * Some of the comments within are dated...
+ * Partition the CURBE between the various users of constant values.
+ *
+ * If the users all fit within the previous allocatation, we avoid changing
+ * the layout because that means reuploading all unit state and uploading new
+ * constant buffers.
*/
static void calculate_curbe_offsets( struct brw_context *brw )
{
struct gl_context *ctx = &brw->ctx;
- /* CACHE_NEW_WM_PROG */
- const GLuint nr_fp_regs = (brw->wm.prog_data->base.nr_params + 15) / 16;
+ /* BRW_NEW_FS_PROG_DATA */
+ const GLuint nr_fp_regs = (brw->wm.base.prog_data->nr_params + 15) / 16;
- /* CACHE_NEW_VS_PROG */
- const GLuint nr_vp_regs = (brw->vs.prog_data->base.base.nr_params + 15) / 16;
+ /* BRW_NEW_VS_PROG_DATA */
+ const GLuint nr_vp_regs = (brw->vs.base.prog_data->nr_params + 15) / 16;
GLuint nr_clip_regs = 0;
GLuint total_regs;
/* _NEW_TRANSFORM */
if (ctx->Transform.ClipPlanesEnabled) {
- GLuint nr_planes = 6 + _mesa_bitcount_64(ctx->Transform.ClipPlanesEnabled);
+ GLuint nr_planes = 6 + _mesa_bitcount(ctx->Transform.ClipPlanesEnabled);
nr_clip_regs = (nr_planes * 4 + 15) / 16;
}
total_regs = nr_fp_regs + nr_vp_regs + nr_clip_regs;
- /* This can happen - what to do? Probably rather than falling
- * back, the best thing to do is emit programs which code the
- * constants as immediate values. Could do this either as a static
- * cap on WM and VS, or adaptively.
+ /* The CURBE allocation size is limited to 32 512-bit units (128 EU
+ * registers, or 1024 floats). See CS_URB_STATE in the gen4 or gen5
+ * (volume 1, part 1) PRMs.
*
- * Unfortunately, this is currently dependent on the results of the
- * program generation process (in the case of wm), so this would
- * introduce the need to re-generate programs in the event of a
- * curbe allocation failure.
- */
- /* Max size is 32 - just large enough to
- * hold the 128 parameters allowed by
- * the fragment and vertex program
- * api's. It's not clear what happens
- * when both VP and FP want to use 128
- * parameters, though.
+ * Note that in brw_fs.cpp we're only loading up to 16 EU registers of
+ * values as push constants before spilling to pull constants, and in
+ * brw_vec4.cpp we're loading up to 32 registers of push constants. An EU
+ * register is 1/2 of one of these URB entry units, so that leaves us 16 EU
+ * regs for clip.
*/
assert(total_regs <= 32);
brw->curbe.vs_start,
brw->curbe.vs_size );
- brw->state.dirty.brw |= BRW_NEW_CURBE_OFFSETS;
+ brw->ctx.NewDriverState |= BRW_NEW_PUSH_CONSTANT_ALLOCATION;
}
}
const struct brw_tracked_state brw_curbe_offsets = {
.dirty = {
.mesa = _NEW_TRANSFORM,
- .brw = BRW_NEW_CONTEXT,
- .cache = CACHE_NEW_VS_PROG | CACHE_NEW_WM_PROG
+ .brw = BRW_NEW_CONTEXT |
+ BRW_NEW_BLORP |
+ BRW_NEW_FS_PROG_DATA |
+ BRW_NEW_VS_PROG_DATA,
},
.emit = calculate_curbe_offsets
};
-/* Define the number of curbes within CS's urb allocation. Multiple
- * urb entries -> multiple curbes. These will be used by
- * fixed-function hardware in a double-buffering scheme to avoid a
- * pipeline stall each time the contents of the curbe is changed.
+/** Uploads the CS_URB_STATE packet.
+ *
+ * Just like brw_vs_state.c and brw_wm_state.c define a URB entry size and
+ * number of entries for their stages, constant buffers do so using this state
+ * packet. Having multiple CURBEs in the URB at the same time allows the
+ * hardware to avoid a pipeline stall between primitives using different
+ * constant buffer contents.
*/
void brw_upload_cs_urb_state(struct brw_context *brw)
{
BEGIN_BATCH(2);
- /* It appears that this is the state packet for the CS unit, ie. the
- * urb entries detailed here are housed in the CS range from the
- * URB_FENCE command.
- */
OUT_BATCH(CMD_CS_URB_STATE << 16 | (2-2));
/* BRW_NEW_URB_FENCE */
ADVANCE_BATCH();
}
-static GLfloat fixed_plane[6][4] = {
+static const GLfloat fixed_plane[6][4] = {
{ 0, 0, -1, 1 },
{ 0, 0, 1, 1 },
{ 0, -1, 0, 1 },
{ 1, 0, 0, 1 }
};
-/* Upload a new set of constants. Too much variability to go into the
- * cache mechanism, but maybe would benefit from a comparison against
- * the current uploaded set of constants.
+/**
+ * Gathers together all the uniform values into a block of memory to be
+ * uploaded into the CURBE, then emits the state packet telling the hardware
+ * the new location.
*/
static void
brw_upload_constant_buffer(struct brw_context *brw)
{
struct gl_context *ctx = &brw->ctx;
+ /* BRW_NEW_PUSH_CONSTANT_ALLOCATION */
const GLuint sz = brw->curbe.total_size;
const GLuint bufsz = sz * 16 * sizeof(GLfloat);
- GLfloat *buf;
+ gl_constant_value *buf;
GLuint i;
gl_clip_plane *clip_planes;
buf = intel_upload_space(brw, bufsz, 64,
&brw->curbe.curbe_bo, &brw->curbe.curbe_offset);
+ STATIC_ASSERT(sizeof(gl_constant_value) == sizeof(float));
+
/* fragment shader constants */
if (brw->curbe.wm_size) {
+ _mesa_load_state_parameters(ctx, brw->fragment_program->Parameters);
+
+ /* BRW_NEW_PUSH_CONSTANT_ALLOCATION */
GLuint offset = brw->curbe.wm_start * 16;
- /* CACHE_NEW_WM_PROG | _NEW_PROGRAM_CONSTANTS: copy uniform values */
- for (i = 0; i < brw->wm.prog_data->base.nr_params; i++) {
- buf[offset + i] = *brw->wm.prog_data->base.param[i];
+ /* BRW_NEW_FS_PROG_DATA | _NEW_PROGRAM_CONSTANTS: copy uniform values */
+ for (i = 0; i < brw->wm.base.prog_data->nr_params; i++) {
+ buf[offset + i] = *brw->wm.base.prog_data->param[i];
}
}
/* clipper constants */
if (brw->curbe.clip_size) {
GLuint offset = brw->curbe.clip_start * 16;
- GLuint j;
+ GLbitfield mask;
/* If any planes are going this way, send them all this way:
*/
for (i = 0; i < 6; i++) {
- buf[offset + i * 4 + 0] = fixed_plane[i][0];
- buf[offset + i * 4 + 1] = fixed_plane[i][1];
- buf[offset + i * 4 + 2] = fixed_plane[i][2];
- buf[offset + i * 4 + 3] = fixed_plane[i][3];
+ buf[offset + i * 4 + 0].f = fixed_plane[i][0];
+ buf[offset + i * 4 + 1].f = fixed_plane[i][1];
+ buf[offset + i * 4 + 2].f = fixed_plane[i][2];
+ buf[offset + i * 4 + 3].f = fixed_plane[i][3];
}
/* Clip planes: _NEW_TRANSFORM plus _NEW_PROJECTION to get to
* clip-space:
*/
clip_planes = brw_select_clip_planes(ctx);
- for (j = 0; j < MAX_CLIP_PLANES; j++) {
- if (ctx->Transform.ClipPlanesEnabled & (1<<j)) {
- buf[offset + i * 4 + 0] = clip_planes[j][0];
- buf[offset + i * 4 + 1] = clip_planes[j][1];
- buf[offset + i * 4 + 2] = clip_planes[j][2];
- buf[offset + i * 4 + 3] = clip_planes[j][3];
- i++;
- }
+ mask = ctx->Transform.ClipPlanesEnabled;
+ while (mask) {
+ const int j = u_bit_scan(&mask);
+ buf[offset + i * 4 + 0].f = clip_planes[j][0];
+ buf[offset + i * 4 + 1].f = clip_planes[j][1];
+ buf[offset + i * 4 + 2].f = clip_planes[j][2];
+ buf[offset + i * 4 + 3].f = clip_planes[j][3];
+ i++;
}
}
/* vertex shader constants */
if (brw->curbe.vs_size) {
+ _mesa_load_state_parameters(ctx, brw->vertex_program->Parameters);
+
GLuint offset = brw->curbe.vs_start * 16;
- /* CACHE_NEW_VS_PROG | _NEW_PROGRAM_CONSTANTS: copy uniform values */
- for (i = 0; i < brw->vs.prog_data->base.base.nr_params; i++) {
- buf[offset + i] = *brw->vs.prog_data->base.base.param[i];
+ /* BRW_NEW_VS_PROG_DATA | _NEW_PROGRAM_CONSTANTS: copy uniform values */
+ for (i = 0; i < brw->vs.base.prog_data->nr_params; i++) {
+ buf[offset + i] = *brw->vs.base.prog_data->param[i];
}
}
if (0) {
for (i = 0; i < sz*16; i+=4)
fprintf(stderr, "curbe %d.%d: %f %f %f %f\n", i/8, i&4,
- buf[i+0], buf[i+1], buf[i+2], buf[i+3]);
+ buf[i+0].f, buf[i+1].f, buf[i+2].f, buf[i+3].f);
}
/* Because this provokes an action (ie copy the constants into the
*/
emit:
+ /* BRW_NEW_URB_FENCE: From the gen4 PRM, volume 1, section 3.9.8
+ * (CONSTANT_BUFFER (CURBE Load)):
+ *
+ * "Modifying the CS URB allocation via URB_FENCE invalidates any
+ * previous CURBE entries. Therefore software must subsequently
+ * [re]issue a CONSTANT_BUFFER command before CURBE data can be used
+ * in the pipeline."
+ */
BEGIN_BATCH(2);
if (brw->curbe.total_size == 0) {
OUT_BATCH((CMD_CONST_BUFFER << 16) | (2 - 2));
(brw->curbe.total_size - 1) + brw->curbe.curbe_offset);
}
ADVANCE_BATCH();
+
+ /* Work around a Broadwater/Crestline depth interpolator bug. The
+ * following sequence will cause GPU hangs:
+ *
+ * 1. Change state so that all depth related fields in CC_STATE are
+ * disabled, and in WM_STATE, only "PS Use Source Depth" is enabled.
+ * 2. Emit a CONSTANT_BUFFER packet.
+ * 3. Draw via 3DPRIMITIVE.
+ *
+ * The recommended workaround is to emit a non-pipelined state change after
+ * emitting CONSTANT_BUFFER, in order to drain the windowizer pipeline.
+ *
+ * We arbitrarily choose 3DSTATE_GLOBAL_DEPTH_CLAMP_OFFSET (as it's small),
+ * and always emit it when "PS Use Source Depth" is set. We could be more
+ * precise, but the additional complexity is probably not worth it.
+ *
+ * BRW_NEW_FRAGMENT_PROGRAM
+ */
+ if (brw->gen == 4 && !brw->is_g4x &&
+ (brw->fragment_program->info.inputs_read & (1 << VARYING_SLOT_POS))) {
+ BEGIN_BATCH(2);
+ OUT_BATCH(_3DSTATE_GLOBAL_DEPTH_OFFSET_CLAMP << 16 | (2 - 2));
+ OUT_BATCH(0);
+ ADVANCE_BATCH();
+ }
}
const struct brw_tracked_state brw_constant_buffer = {
.dirty = {
.mesa = _NEW_PROGRAM_CONSTANTS,
- .brw = (BRW_NEW_URB_FENCE | /* Implicit - hardware requires this, not used above */
- BRW_NEW_PSP | /* Implicit - hardware requires this, not used above */
- BRW_NEW_CURBE_OFFSETS |
- BRW_NEW_BATCH),
- .cache = (CACHE_NEW_VS_PROG |
- CACHE_NEW_WM_PROG)
+ .brw = BRW_NEW_BATCH |
+ BRW_NEW_BLORP |
+ BRW_NEW_PUSH_CONSTANT_ALLOCATION |
+ BRW_NEW_FRAGMENT_PROGRAM |
+ BRW_NEW_FS_PROG_DATA |
+ BRW_NEW_PSP | /* Implicit - hardware requires this, not used above */
+ BRW_NEW_URB_FENCE |
+ BRW_NEW_VS_PROG_DATA,
},
.emit = brw_upload_constant_buffer,
};
projects / mesa.git / blobdiff