initial seed: retrofit campaign lineage from local working trees

panvk-bifrost campaigns (r1..r4 Vulkan compositor + r5.video1 Vulkan
video decode) shipped before this repo existed; the deliverable
patches live in marfrit-packages, but the reasoning chain, phase docs,
and source-state evidence lived only in local working trees on the
development host.

This retrofit imports:
- mesa-panvk-bifrost/   — r1..r4 era phase docs (iter1..iter18)
                          (libmali stub blobs at iter18/blob/ excluded
                          — 109MB of RE artifacts replaced with a README
                          pointer)
- mesa-panvk-bifrost-video/ — sibling campaign phase docs + probe
- evidence/             — frozen .tgz source snapshots at each milestone
                          (basis for the 0005 patch diff generation)

Future iterations should branch off here from day one, so each iter is
a commit rather than a snapshot. See [[feedback-session-local-process-pins]]
for the process drift this retrofit closes.

Total: 1.9 MB across 124 files.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

mesa-panvk-bifrost/phase0_evidence/iter2_image_clear_run.txt

@@ -0,0 +1,73 @@
+iter2 minimal image-clear probe — captured 2026-05-19 on ohm
+(PineTab2 v2.0, RK3566, Mali-G52 r1 MC1, Mesa 26.0.6, kernel 7.0.0-danctnix1-6)
+
+Source: panvk-bifrost/iter2/{probe_image_clear.c, Makefile}
+Deployed to: /tmp/panvk-iter2/
+Build: clean (no warnings with -Wall -Wextra)
+
+===== RUN #1 (no validation layer) =====
+$ PAN_I_WANT_A_BROKEN_VULKAN_DRIVER=1 ./probe_image_clear
+
+[step] vkCreateInstance
+[step] vkEnumeratePhysicalDevices
+WARNING: panvk is not a conformant Vulkan implementation, testing use only.
+[info] gpu='Mali-G52 r1 MC1' apiVersion=1.0.335
+[info] R8G8B8A8_UNORM optimalTilingFeatures=0x8000dd83
+[step] vkCreateDevice
+[step] vkCreateImage (4x4 R8G8B8A8_UNORM optimal-tiled)
+[info] image memReq size=4096 alignment=4096 typeBits=0x7
+[step] vkAllocateMemory + vkBindImageMemory (device-local)
+[step] vkCreateBuffer (staging, host-visible)
+[step] vkBeginCommandBuffer + record image clear + copy
+[step] vkQueueSubmit + vkWaitForFences (5s timeout)
+[step] vkInvalidateMappedMemoryRanges + readback
+[info] expected pixel = 0x44332211 (R=0x11 G=0x22 B=0x33 A=0x44)
+[info] mismatches = 0 / 16
+[PASS] PanVk-Bifrost image clear+copy: all 16 pixels match.
+===== RC=0 =====
+
+===== RUN #2 (VK_LAYER_KHRONOS_validation enabled) =====
+[same step trace, no validation warnings/errors emitted]
+[PASS] PanVk-Bifrost image clear+copy: all 16 pixels match.
+===== RC=0 =====
+
+===== STABILITY: 5 consecutive reruns =====
+[info] mismatches = 0 / 16    [PASS]
+[info] mismatches = 0 / 16    [PASS]
+[info] mismatches = 0 / 16    [PASS]
+[info] mismatches = 0 / 16    [PASS]
+[info] mismatches = 0 / 16    [PASS]
+
+7/7 runs PASS.
+
+===== KEY OBSERVATIONS =====
+
+1. R8G8B8A8_UNORM optimalTilingFeatures = 0x8000dd83:
+     bit 0  (0x0001) SAMPLED_IMAGE
+     bit 1  (0x0002) STORAGE_IMAGE
+     bit 7  (0x0080) COLOR_ATTACHMENT
+     bit 8  (0x0100) COLOR_ATTACHMENT_BLEND
+     bit 10 (0x0400) BLIT_SRC
+     bit 11 (0x0800) BLIT_DST
+     bit 12 (0x1000) SAMPLED_IMAGE_FILTER_LINEAR
+     bit 14 (0x4000) TRANSFER_SRC
+     bit 15 (0x8000) TRANSFER_DST
+     bit 31 (0x80000000) — extended/disjoint flag
+
+2. Image memReq size=4096, alignment=4096 for a 4x4 RGBA8 image.
+   Logical pixel size: 4*4*4 = 64 bytes.
+   Allocated:          4096 bytes (one Mali page).
+   So Bifrost pages the image out to a full page even for tiny images. Expected.
+
+3. UNORM float→byte conversion is exact:
+     R = 17.0f/255.0f → 0x11   ✓
+     G = 34.0f/255.0f → 0x22   ✓
+     B = 51.0f/255.0f → 0x33   ✓
+     A = 68.0f/255.0f → 0x44   ✓
+   No rounding error in any of the 16 pixels.
+
+4. Bifrost optimal-tiling → linear-buffer detile correct:
+   All 16 pixels read back as 0x44332211 with no shuffling.
+   The vkCmdCopyImageToBuffer path handles the Bifrost tile layout transform.
+
+No GPU faults, no MMU faults, no kernel-side panfrost messages across 7 runs.