marfrit-packages/arch/mesa-panvk-bifrost/0003-panvk-bifrost-vk-ext-transform-feedback.patch

--- a/src/panfrost/vulkan/panvk_shader.h	2026-04-29 22:19:00.000000000 +0200
+++ b/src/panfrost/vulkan/panvk_shader.h	2026-05-20 18:52:53.312698258 +0200
@@ -150,6 +150,10 @@
    struct {
 #if PAN_ARCH < 9
       int32_t raw_vertex_offset;
+      uint32_t num_vertices;       /* iter13: XFB needs per-draw vertex count */
+      /* aligned_u64 attribute below inserts the 4-byte alignment gap
+       * after num_vertices automatically — no explicit pad needed. */
+      aligned_u64 xfb_address[4];  /* iter13: 4 transform feedback buffer base addresses */
 #endif
       int32_t first_vertex;
       int32_t base_instance;
--- a/src/panfrost/vulkan/panvk_vX_physical_device.c	2026-05-20 19:09:29.711145446 +0200
+++ b/src/panfrost/vulkan/panvk_vX_physical_device.c	2026-05-20 18:52:54.832720445 +0200
@@ -169,6 +169,7 @@
       .EXT_provoking_vertex = true,
       .EXT_queue_family_foreign = true,
       .EXT_robustness2 = true,
+      .EXT_transform_feedback = PAN_ARCH < 9,   /* iter13: JM-class only for now */
       .EXT_sampler_filter_minmax = PAN_ARCH >= 10,
       .EXT_scalar_block_layout = true,
       .EXT_separate_stencil_usage = true,
@@ -495,6 +496,10 @@
       .robustImageAccess2 = false,
       .nullDescriptor = true,
 
+      /* VK_EXT_transform_feedback (iter13) */
+      .transformFeedback = PAN_ARCH < 9,
+      .geometryStreams = false,
+
       /* VK_KHR_shader_clock */
       .shaderSubgroupClock = device->kmod.dev->props.gpu_can_query_timestamp,
       .shaderDeviceClock = device->kmod.dev->props.timestamp_device_coherent,
@@ -1020,6 +1025,18 @@
       .robustStorageBufferAccessSizeAlignment = 1,
       .robustUniformBufferAccessSizeAlignment = 1,
 
+      /* VK_EXT_transform_feedback (iter13) */
+      .maxTransformFeedbackStreams = 1,
+      .maxTransformFeedbackBuffers = 4,
+      .maxTransformFeedbackBufferSize = UINT32_MAX,
+      .maxTransformFeedbackStreamDataSize = 512,
+      .maxTransformFeedbackBufferDataSize = 512,
+      .maxTransformFeedbackBufferDataStride = 2048,
+      .transformFeedbackQueries = false,
+      .transformFeedbackStreamsLinesTriangles = false,
+      .transformFeedbackRasterizationStreamSelect = false,
+      .transformFeedbackDraw = false,
+
       /* VK_EXT_shader_object */
       /* We do not currently support VK_EXT_shader_object but this is used
        * internally by vk_shader
--- a/src/panfrost/vulkan/panvk_vX_shader.c	2026-04-29 22:19:00.000000000 +0200
+++ b/src/panfrost/vulkan/panvk_vX_shader.c	2026-05-20 18:52:56.556745611 +0200
@@ -21,6 +21,7 @@
 #include "panvk_physical_device.h"
 #include "panvk_sampler.h"
 #include "panvk_shader.h"
+#include "pan_nir.h"   /* iter13: pan_nir_lower_xfb */
 
 #include "spirv/nir_spirv.h"
 #include "util/memstream.h"
@@ -100,6 +101,20 @@
    case nir_intrinsic_load_raw_vertex_offset_pan:
       val = load_sysval(b, graphics, bit_size, vs.raw_vertex_offset);
       break;
+   case nir_intrinsic_load_num_vertices:    /* iter13: XFB index calc */
+      val = load_sysval(b, graphics, bit_size, vs.num_vertices);
+      break;
+   case nir_intrinsic_load_xfb_address: {   /* iter13: XFB buffer N base address */
+      unsigned idx = nir_intrinsic_base(intr);
+      switch (idx) {
+      case 0: val = load_sysval(b, graphics, bit_size, vs.xfb_address[0]); break;
+      case 1: val = load_sysval(b, graphics, bit_size, vs.xfb_address[1]); break;
+      case 2: val = load_sysval(b, graphics, bit_size, vs.xfb_address[2]); break;
+      case 3: val = load_sysval(b, graphics, bit_size, vs.xfb_address[3]); break;
+      default: return false;
+      }
+      break;
+   }
    case nir_intrinsic_load_layer_id:
       assert(b->shader->info.stage == MESA_SHADER_FRAGMENT);
       val = load_sysval(b, graphics, bit_size, layer_id);
@@ -457,6 +472,7 @@
             core_max_id);
 
    pan_preprocess_nir(nir, pdev->kmod.dev->props.gpu_id);
+
 }
 
 static void
@@ -870,6 +886,18 @@
             nir_var_shader_in | nir_var_shader_out, UINT32_MAX);
    NIR_PASS(_, nir, nir_lower_io, nir_var_shader_in | nir_var_shader_out,
             glsl_type_size, nir_lower_io_use_interpolated_input_intrinsics);
+
+#if PAN_ARCH < 9
+   /* iter13: VK_EXT_transform_feedback — runs AFTER nir_lower_io so that
+    * shader outputs are now store_output intrinsics that pan_nir_lower_xfb
+    * can rewrite to nir_store_global+nir_load_xfb_address. */
+   if (nir->info.stage == MESA_SHADER_VERTEX &&
+       nir->info.has_transform_feedback_varyings) {
+      NIR_PASS(_, nir, nir_opt_constant_folding);
+      NIR_PASS(_, nir, nir_io_add_intrinsic_xfb_info);
+      NIR_PASS(_, nir, pan_nir_lower_xfb);
+   }
+#endif
 }
 
 static VkResult
@@ -1288,6 +1316,9 @@
       .view_mask = (state && state->rp) ? state->rp->view_mask : 0,
       .robust2_modes = robust2_modes,
       .robust_descriptors = dev->vk.enabled_features.nullDescriptor,
+      /* iter13: XFB shaders must disable IDVS (matches Panfrost-Gallium). */
+      .no_idvs = (info->stage == MESA_SHADER_VERTEX) &&
+                 info->nir->info.has_transform_feedback_varyings,
    };
 
    switch (info->stage) {
--- a/src/panfrost/vulkan/panvk_cmd_draw.h	2026-04-29 22:19:00.000000000 +0200
+++ b/src/panfrost/vulkan/panvk_cmd_draw.h	2026-05-20 18:52:57.748763011 +0200
@@ -135,6 +135,19 @@
    struct panvk_graphics_sysvals sysvals;
 
 #if PAN_ARCH < 9
+   /* iter13: VK_EXT_transform_feedback state (JM-class only for now). */
+   struct {
+      bool active;
+      uint32_t buffer_count;
+      struct {
+         uint64_t addr;
+         uint64_t offset;
+         uint64_t size;
+      } buffers[4];
+   } xfb;
+#endif
+
+#if PAN_ARCH < 9
    struct panvk_shader_link link;
 #endif
 
--- a/src/panfrost/vulkan/panvk_vX_cmd_draw.c	2026-04-29 22:19:00.000000000 +0200
+++ b/src/panfrost/vulkan/panvk_vX_cmd_draw.c	2026-05-20 19:10:23.031919662 +0200
@@ -10,6 +10,7 @@
 #include "panvk_entrypoints.h"
 
 #include "pan_desc.h"
+#include "pan_compiler.h"   /* PAN_SHADER_OOB_ADDRESS */
 #include "pan_util.h"
 
 static void
@@ -722,6 +723,35 @@
    set_gfx_sysval(cmdbuf, dirty_sysvals, vs.raw_vertex_offset,
                   info->vertex.raw_offset);
    set_gfx_sysval(cmdbuf, dirty_sysvals, layer_id, info->layer_id);
+
+   /* iter13: VK_EXT_transform_feedback sysvals — always set (per draw),
+    * reflect bound XFB state. set_gfx_sysval is a no-op if value unchanged. */
+   set_gfx_sysval(cmdbuf, dirty_sysvals, vs.num_vertices, info->vertex.count);
+   {
+      const struct panvk_cmd_graphics_state *_gfx = &cmdbuf->state.gfx;
+      /* iter13: default each XFB buffer address to PAN_SHADER_OOB_ADDRESS
+       * (= 1<<63). This is the Panfrost-Gallium memory-sink idiom — the
+       * Bifrost MMU silently discards stores to this address, so a pipeline
+       * with XFB outputs used in a non-XFB draw (or in an XFB draw with
+       * fewer bound buffers than the shader declares) is safe instead of
+       * faulting. See gallium/drivers/panfrost/pan_cmdstream.c PAN_SYSVAL_XFB. */
+      uint64_t _xa0 = PAN_SHADER_OOB_ADDRESS, _xa1 = PAN_SHADER_OOB_ADDRESS,
+               _xa2 = PAN_SHADER_OOB_ADDRESS, _xa3 = PAN_SHADER_OOB_ADDRESS;
+      if (_gfx->xfb.active) {
+         if (_gfx->xfb.buffer_count > 0 && _gfx->xfb.buffers[0].addr)
+            _xa0 = _gfx->xfb.buffers[0].addr + _gfx->xfb.buffers[0].offset;
+         if (_gfx->xfb.buffer_count > 1 && _gfx->xfb.buffers[1].addr)
+            _xa1 = _gfx->xfb.buffers[1].addr + _gfx->xfb.buffers[1].offset;
+         if (_gfx->xfb.buffer_count > 2 && _gfx->xfb.buffers[2].addr)
+            _xa2 = _gfx->xfb.buffers[2].addr + _gfx->xfb.buffers[2].offset;
+         if (_gfx->xfb.buffer_count > 3 && _gfx->xfb.buffers[3].addr)
+            _xa3 = _gfx->xfb.buffers[3].addr + _gfx->xfb.buffers[3].offset;
+      }
+      set_gfx_sysval(cmdbuf, dirty_sysvals, vs.xfb_address[0], _xa0);
+      set_gfx_sysval(cmdbuf, dirty_sysvals, vs.xfb_address[1], _xa1);
+      set_gfx_sysval(cmdbuf, dirty_sysvals, vs.xfb_address[2], _xa2);
+      set_gfx_sysval(cmdbuf, dirty_sysvals, vs.xfb_address[3], _xa3);
+   }
 #endif
 
    if (dyn_gfx_state_dirty(cmdbuf, CB_BLEND_CONSTANTS)) {
--- a/src/panfrost/vulkan/meson.build	2026-04-29 22:19:00.000000000 +0200
+++ b/src/panfrost/vulkan/meson.build	2026-05-20 18:53:04.484861338 +0200
@@ -73,6 +73,7 @@
 jm_inc_dir = ['jm']
 jm_files = [
   'jm/panvk_vX_bind_queue.c',
+  'jm/panvk_vX_cmd_xfb.c',   # iter13
   'jm/panvk_vX_cmd_buffer.c',
   'jm/panvk_vX_cmd_dispatch.c',
   'jm/panvk_vX_cmd_draw.c',
--- a/src/panfrost/vulkan/jm/panvk_vX_cmd_buffer.c	2026-04-29 22:19:00.000000000 +0200
+++ b/src/panfrost/vulkan/jm/panvk_vX_cmd_buffer.c	2026-05-20 19:10:26.163965149 +0200
@@ -473,5 +473,12 @@
 
    vk_command_buffer_begin(&cmdbuf->vk, pBeginInfo);
 
+#if PAN_ARCH < 9
+   /* iter13: clear XFB state on Begin so a reused command buffer does not
+    * inherit stale xfb.buffer_count / xfb.active / xfb.buffers[] from a
+    * prior recording. */
+   memset(&cmdbuf->state.gfx.xfb, 0, sizeof(cmdbuf->state.gfx.xfb));
+#endif
+
    return VK_SUCCESS;
 }
--- a/src/panfrost/vulkan/jm/panvk_vX_cmd_xfb.c	2026-05-18 12:50:53.067999996 +0200
+++ b/src/panfrost/vulkan/jm/panvk_vX_cmd_xfb.c	2026-05-20 19:10:27.175979847 +0200
@@ -0,0 +1,111 @@
+/*
+ * Copyright © 2026 mfritsche / claude-noether
+ * SPDX-License-Identifier: MIT
+ *
+ * iter13: VK_EXT_transform_feedback command handlers for the JM
+ * architecture path (Bifrost v6/v7 + Valhall-JM v9).
+ *
+ * The runtime contract:
+ *   - vkCmdBindTransformFeedbackBuffersEXT: stash (gpu_addr, offset, size)
+ *     for each slot into cmdbuf->state.gfx.xfb.buffers[].
+ *   - vkCmdBeginTransformFeedbackEXT: set cmdbuf->state.gfx.xfb.active = true.
+ *     Mark sysvals dirty so the next draw re-emits vs.xfb_address[].
+ *   - vkCmdEndTransformFeedbackEXT: set active = false.
+ *
+ * Counter buffers (firstCounterBuffer/counterBufferCount/pCounterBuffers/
+ * pCounterBufferOffsets) are accepted by API but ignored — v1 doesn't
+ * support pause/resume. transformFeedbackDraw is advertised as false.
+ *
+ * Per-draw integration: jm/panvk_vX_cmd_draw.c reads cmdbuf->state.gfx.xfb
+ * and populates vs.xfb_address[i] for shader use. The pan_nir_lower_xfb
+ * pass in panvk_vX_shader.c emits nir_load_xfb_address(i) which lowers
+ * (via panvk_vX_shader.c sysval handler) to a load from the per-draw
+ * sysval push area.
+ */
+
+#include "vk_log.h"
+#include "util/log.h"
+
+#include "panvk_cmd_buffer.h"
+#include "panvk_cmd_draw.h"
+#include "panvk_buffer.h"
+#include "panvk_entrypoints.h"
+
+VKAPI_ATTR void VKAPI_CALL
+panvk_per_arch(CmdBindTransformFeedbackBuffersEXT)(
+   VkCommandBuffer commandBuffer,
+   uint32_t firstBinding,
+   uint32_t bindingCount,
+   const VkBuffer *pBuffers,
+   const VkDeviceSize *pOffsets,
+   const VkDeviceSize *pSizes)
+{
+   VK_FROM_HANDLE(panvk_cmd_buffer, cmdbuf, commandBuffer);
+   struct panvk_cmd_graphics_state *gfx = &cmdbuf->state.gfx;
+
+   for (uint32_t i = 0; i < bindingCount; i++) {
+      uint32_t slot = firstBinding + i;
+      if (slot >= 4)
+         continue;
+
+      VK_FROM_HANDLE(panvk_buffer, buf, pBuffers[i]);
+      gfx->xfb.buffers[slot].addr = panvk_buffer_gpu_ptr(buf, 0);
+      gfx->xfb.buffers[slot].offset = pOffsets[i];
+      gfx->xfb.buffers[slot].size =
+         (pSizes != NULL && pSizes[i] != VK_WHOLE_SIZE)
+            ? pSizes[i]
+            : (buf->vk.size - pOffsets[i]);
+   }
+
+   if (firstBinding + bindingCount > gfx->xfb.buffer_count)
+      gfx->xfb.buffer_count = firstBinding + bindingCount;
+}
+
+VKAPI_ATTR void VKAPI_CALL
+panvk_per_arch(CmdBeginTransformFeedbackEXT)(
+   VkCommandBuffer commandBuffer,
+   uint32_t firstCounterBuffer,
+   uint32_t counterBufferCount,
+   const VkBuffer *pCounterBuffers,
+   const VkDeviceSize *pCounterBufferOffsets)
+{
+   VK_FROM_HANDLE(panvk_cmd_buffer, cmdbuf, commandBuffer);
+   struct panvk_cmd_graphics_state *gfx = &cmdbuf->state.gfx;
+
+   /* Counter buffers ignored in v1 — see VkPhysicalDeviceTransformFeedback
+    * PropertiesEXT.transformFeedbackDraw = false in panvk_vX_physical_device.c.
+    * App is spec-compliant if it does not pass counter buffers (which our
+    * features advertisement allows), but warn loudly if it does so we do not
+    * silently produce wrong capture state. */
+   (void)firstCounterBuffer;
+   (void)pCounterBufferOffsets;
+   if (counterBufferCount > 0 && pCounterBuffers != NULL) {
+      mesa_logw("panvk: CmdBeginTransformFeedbackEXT: counter buffers not "
+                "implemented (transformFeedbackDraw=false); XFB resume will "
+                "restart at buffer offset 0");
+   }
+
+   gfx->xfb.active = true;
+   /* Per-draw set_gfx_sysval picks up the change automatically — no
+    * explicit dirty marking required (set_gfx_sysval uses memcmp +
+    * BITSET to detect state diffs and re-emit sysvals). */
+}
+
+VKAPI_ATTR void VKAPI_CALL
+panvk_per_arch(CmdEndTransformFeedbackEXT)(
+   VkCommandBuffer commandBuffer,
+   uint32_t firstCounterBuffer,
+   uint32_t counterBufferCount,
+   const VkBuffer *pCounterBuffers,
+   const VkDeviceSize *pCounterBufferOffsets)
+{
+   VK_FROM_HANDLE(panvk_cmd_buffer, cmdbuf, commandBuffer);
+   struct panvk_cmd_graphics_state *gfx = &cmdbuf->state.gfx;
+
+   (void)firstCounterBuffer;
+   (void)counterBufferCount;
+   (void)pCounterBuffers;
+   (void)pCounterBufferOffsets;
+
+   gfx->xfb.active = false;
+}