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Phase 8: wire IDCT QPU dispatch through public API

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daedalus_ctx now owns a v3d_runner when V3D is available. The
public API's dispatch_vp9_idct8 routes QPU calls through a
new dispatch_idct8_qpu helper that: (1) lazy-creates the cycle 1
v4 pipeline on first use, (2) allocates 3 host-visible SSBOs
per call (coeffs/dst/meta), (3) memcpy host->GPU, (4) dispatch
with the v4 32-blocks-per-WG geometry, (5) memcpy GPU->host.

Per-call alloc is intentional for Phase 8 correctness-first
scope; buffer-pool perf optimization is deferred.

Added daedalus_ctx_create_no_qpu() for fast-path callers that
know they want CPU only.

test_api_idct extended to a 3-mode matrix: CPU forced, QPU
forced, AUTO recipe. All three deliver 4096/4096 bit-exact
on hertz with V3D 7.1.7.0:

  recipe substrate for VP9_IDCT8: 2 (QPU)
  [CPU] 4096/4096 bit-exact
  [QPU] 4096/4096 bit-exact (real QPU dispatch through the API)
  [AUTO] 4096/4096 bit-exact (recipe routes to QPU)

Next Phase 8 sub-step: same wiring pattern for cycle 2 LPF wd=4
and cycle 4 LPF wd=8 (the other two recipe-QPU kernels).
Cycle 3 MC and cycle 5 CDEF only need the dispatch hook
(recipe routes to CPU; QPU stays opportunistic via explicit
override).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
This commit is contained in:
Markus Fritsche
2026-05-18 13:55:55 +00:00
parent 760f6a4060
commit 1085c5699c
4 changed files with 194 additions and 32 deletions
Download Patch File Download Diff File Expand all files Collapse all files
tests/test_api_idct.c
+33 -18
View File
@@ -37,14 +37,37 @@ static inline uint64_t xs(void) {
return xs_state = x;
}
int main(void)
static int run_once(daedalus_substrate force,
const int16_t *coeffs,
const daedalus_idct8_meta *meta,
const uint8_t *dst_initial,
const uint8_t *dst_ref,
const char *label)
{
daedalus_ctx *ctx = daedalus_ctx_create();
if (!ctx) { fprintf(stderr, "ctx create failed\n"); return 1; }
int has_qpu = daedalus_ctx_has_qpu(ctx);
printf(" [%s] has_qpu=%d force=%d\n", label, has_qpu, (int) force);
if (force == DAEDALUS_SUBSTRATE_QPU && !has_qpu) {
printf(" SKIP — QPU unavailable on this host\n");
daedalus_ctx_destroy(ctx); return 0;
}
uint8_t dst[DST_BYTES];
memcpy(dst, dst_initial, DST_BYTES);
int rc = daedalus_dispatch_vp9_idct8(ctx, force, dst, DST_STRIDE,
coeffs, N_BLOCKS, meta);
if (rc) { fprintf(stderr, " dispatch rc=%d\n", rc); daedalus_ctx_destroy(ctx); return 1; }
int diffs = 0;
for (int i = 0; i < DST_BYTES; i++) if (dst[i] != dst_ref[i]) diffs++;
printf(" %d / %d bytes bit-exact (%.4f%%)\n",
DST_BYTES - diffs, DST_BYTES, 100.0 * (DST_BYTES - diffs) / DST_BYTES);
daedalus_ctx_destroy(ctx);
return diffs == 0 ? 0 : 1;
}
int main(void)
{
printf("=== Phase 8 API smoke: VP9 IDCT 8x8 via recipe dispatch ===\n");
printf(" has_qpu: %d (Phase 8 skeleton: NEON-only)\n",
daedalus_ctx_has_qpu(ctx));
printf(" recipe substrate for VP9_IDCT8: %d (1=CPU, 2=QPU)\n",
(int) daedalus_recipe_substrate_for(DAEDALUS_KERNEL_VP9_IDCT8));
@@ -61,9 +84,9 @@ int main(void)
}
}
uint8_t dst_ref[DST_BYTES], dst_api[DST_BYTES];
uint8_t dst_ref[DST_BYTES], dst_initial[DST_BYTES];
for (int i = 0; i < DST_BYTES; i++)
dst_ref[i] = dst_api[i] = (uint8_t)(xs() & 0xff);
dst_ref[i] = dst_initial[i] = (uint8_t)(xs() & 0xff);
/* 8x8 grid of 8x8 blocks. Block (bx, by) at byte offset
* by*8*stride + bx*8. */
@@ -87,17 +110,9 @@ int main(void)
DST_STRIDE, scratch, 64);
}
/* Dispatch through the public API. */
int rc = daedalus_recipe_dispatch_vp9_idct8(ctx, dst_api, DST_STRIDE,
coeffs, N_BLOCKS, meta);
if (rc != 0) { fprintf(stderr, "API dispatch failed rc=%d\n", rc); return 1; }
/* Compare. */
int diffs = 0;
for (int i = 0; i < DST_BYTES; i++) if (dst_ref[i] != dst_api[i]) diffs++;
printf(" bytes bit-exact: %d / %d (%.4f%%)\n",
DST_BYTES - diffs, DST_BYTES, 100.0 * (DST_BYTES - diffs) / DST_BYTES);
daedalus_ctx_destroy(ctx);
return diffs == 0 ? 0 : 1;
int fail = 0;
fail |= run_once(DAEDALUS_SUBSTRATE_CPU, coeffs, meta, dst_initial, dst_ref, "CPU");
fail |= run_once(DAEDALUS_SUBSTRATE_QPU, coeffs, meta, dst_initial, dst_ref, "QPU");
fail |= run_once(DAEDALUS_SUBSTRATE_AUTO, coeffs, meta, dst_initial, dst_ref, "AUTO");
return fail;
}