diff --git a/.github/workflows/qcom-build-pkg-reusable-workflow.yml b/.github/workflows/qcom-build-pkg-reusable-workflow.yml
index 00f2e79..8829f21 100644
--- a/.github/workflows/qcom-build-pkg-reusable-workflow.yml
+++ b/.github/workflows/qcom-build-pkg-reusable-workflow.yml
@@ -64,6 +64,25 @@ on:
         type: boolean
         default: false
 
+      srcpkg-artifact:
+        description: |
+          Name of a GitHub Actions artifact containing a pre-prepared source tree
+          to use as srcpkg/. When set, the debian-ref checkout is skipped and the
+          artifact is downloaded instead. Used for packages like pkg-linux-qcom
+          where the source tree is assembled at CI time rather than managed in a
+          single git repository.
+        type: string
+        default: ""
+
+      assemble-orig:
+        description: |
+          When true, generate-source-package creates the .orig.tar.gz directly
+          from the source tree and invokes dpkg-buildpackage -S, bypassing gbp.
+          Use for packages whose source tree is assembled at CI time with no
+          upstream tarball available via gbp or pristine-tar.
+        type: boolean
+        default: false
+
     secrets:
       DEBUSINE_USER:
         required: false
@@ -95,7 +114,8 @@ permissions:
   packages: read
 
 env:
-  DEBUSINE_ACTION_REF: main
+  # TODO: update to main once feat/generate-source-package-non-gbp-quilt is merged.
+  DEBUSINE_ACTION_REF: feat/generate-source-package-non-gbp-quilt
 
 jobs:
   resolve:
@@ -252,6 +272,7 @@ jobs:
             lib
 
       - name: Checkout Repository
+        if: ${{ inputs.srcpkg-artifact == '' }}
         uses: actions/checkout@v5
         with:
           ref: ${{ inputs.debian-ref }}
@@ -259,6 +280,27 @@ jobs:
           fetch-depth: 0
           fetch-tags: true
 
+      - name: Download pre-prepared source tree
+        if: ${{ inputs.srcpkg-artifact != '' }}
+        uses: actions/download-artifact@v8
+        with:
+          name: ${{ inputs.srcpkg-artifact }}
+          path: /tmp/srcpkg-artifact
+
+      - name: Extract pre-prepared source tree
+        if: ${{ inputs.srcpkg-artifact != '' }}
+        run: |
+          # The artifact is a tar.gz archive created by the caller to preserve
+          # Unix execute permissions on kernel build scripts. zip format (used
+          # by actions/upload-artifact) strips execute bits; tar does not.
+          # --strip-components=1 extracts the top-level directory directly into
+          # srcpkg/ without depending on its name inside the archive.
+          # The artifact contains exactly one *.tar.gz, so the glob below stays
+          # unambiguous while decoupling this step from the producer's filename.
+          mkdir srcpkg
+          tar xzf /tmp/srcpkg-artifact/*.tar.gz \
+            -C srcpkg --strip-components=1
+
       - name: Prepare release
         if: ${{ inputs.release }}
         env:
@@ -273,6 +315,7 @@ jobs:
         id: generate-source-package
         env:
           SUITE_INPUT: ${{ needs.resolve.outputs.target_suite }}
+          DEBUSINE_ASSEMBLE_ORIG: ${{ inputs.assemble-orig }}
         run: |
           set -ex
           SUITE="$SUITE_INPUT" debusine-action/lib/generate-source-package
@@ -354,13 +397,29 @@ jobs:
             lib
 
       - name: Checkout Repository
-        if: ${{ needs.resolve.outputs.family == 'debian' && needs.resolve.outputs.force_docker_build != 'true' }}
+        if: ${{ needs.resolve.outputs.family == 'debian' && needs.resolve.outputs.force_docker_build != 'true' && inputs.srcpkg-artifact == '' }}
         uses: actions/checkout@v5
         with:
           ref: ${{ inputs.debian-ref }}
           path: srcpkg
           fetch-depth: 1
 
+      - name: Download pre-prepared source tree
+        if: ${{ needs.resolve.outputs.family == 'debian' && inputs.srcpkg-artifact != '' }}
+        uses: actions/download-artifact@v8
+        with:
+          name: ${{ inputs.srcpkg-artifact }}
+          path: /tmp/srcpkg-artifact
+
+      - name: Extract pre-prepared source tree
+        if: ${{ needs.resolve.outputs.family == 'debian' && inputs.srcpkg-artifact != '' }}
+        run: |
+          # Single *.tar.gz in the artifact; glob decouples from the
+          # producer's filename (see build-job extract step for rationale).
+          mkdir srcpkg
+          tar xzf /tmp/srcpkg-artifact/*.tar.gz \
+            -C srcpkg --strip-components=1
+
       - name: Validate installability from Debusine CI workspace
         if: ${{ needs.resolve.outputs.family == 'debian' && needs.resolve.outputs.force_docker_build != 'true' }}
         env: