CI: Add RISC-V runner support and matrix-based workflow

.github/workflows/ci.yml

@@ -23,6 +23,11 @@ on:
         required: true
         type: number
         default: 0
+      riscv64_count:
+        description: 'Number of riscv64 (QEMU) runners'
+        required: true
+        type: number
+        default: 0
 
 defaults:
   run:
@@ -46,8 +51,14 @@ jobs:
         run: |
           X86=$(seq 1 "${{ github.event.inputs.x86_64_count }}" | jq -cs '[.[] | {"os":"ubuntu-latest", "runner_id":.}]')
           ARM=$(seq 1 "${{ github.event.inputs.aarch64_count }}" | jq -cs '[.[] | {"os":"ubuntu-24.04-arm", "runner_id":.}]')
-          echo "matrix=$(jq -cn --argjson a "$X86" --argjson b "$ARM" '{include: ($a + $b)}')" >> $GITHUB_OUTPUT
-          echo "matrix_count=$(( ${{ github.event.inputs.x86_64_count }} + ${{ github.event.inputs.aarch64_count }} ))" >> $GITHUB_OUTPUT
+          RISCV=$(seq 1 "${{ github.event.inputs.riscv64_count }}" | jq -cs '[.[] | {"os":"ubuntu-latest", "runner_id":., "riscv":true}]')
+          #echo "matrix=$(jq -cn --argjson a "$X86" --argjson b "$ARM" '{include: ($a + $b)}')" >> $GITHUB_OUTPUT
+          #echo "matrix_count=$(( ${{ github.event.inputs.x86_64_count }} + ${{ github.event.inputs.aarch64_count }} ))" >> $GITHUB_OUTPUT
+          echo "matrix=$(jq -cn --argjson a "$X86" --argjson b "$ARM" --argjson c "$RISCV" '{include: ($a + $b + $c)}')" >> $GITHUB_OUTPUT
+          echo "matrix_count=$(( \
+                  ${{ github.event.inputs.x86_64_count }} + \
+                  ${{ github.event.inputs.aarch64_count }} + \
+                  ${{ github.event.inputs.riscv64_count }} ))" >> $GITHUB_OUTPUT
           WINX86=$(seq 1 "${{ github.event.inputs.win_x86_64_count }}" | jq -cs '[.[] | {"os":"windows-latest", "runner_id":.}]')
           echo "matrix_win=$(jq -cn --argjson a "$WINX86" '{include: ($a)}')" >> $GITHUB_OUTPUT
           echo "matrix_win_count=$(( ${{ github.event.inputs.win_x86_64_count }} ))" >> $GITHUB_OUTPUT
@@ -95,7 +106,11 @@ jobs:
           chmod +x runner
       - name: Register Runner
         run: |
-          if [[ "$(uname -m)" == "aarch64" ]]; then
+          #if [[ "${{ matrix.riscv }}" == "true" ]]; then
+          if [[ "${{ matrix.riscv || false }}" == "true" ]]; then  
+            printf '%s\n' '${{ secrets.RUNNER_REGISTRATION_X86_64 }}' > .runner
+            mv config_riscv64.yaml config.yaml
+          elif [[ "$(uname -m)" == "aarch64" ]]; then
             printf '%s\n' '${{ secrets.RUNNER_REGISTRATION_AARCH64 }}' > .runner
             mv config_aarch64.yaml config.yaml
           else
@@ -122,13 +137,15 @@ jobs:
       - name: Get Internal Env-Vars
         uses: crazy-max/ghaction-github-runtime@v3
       - name: Start Cacheproxy
+        if: ${{ !env.ACT }}
         run: |
           ./cacheproxy/genconfig.sh
           docker network create runnernet
           docker run --rm --pull=always -d --network runnernet --name cacheproxy -v ./cacheproxy:/etc/caddy caddy:2
           echo "ACTIONS_CACHE_URL_V2=http://cacheproxy:8080/" >> .env
           echo "ACTIONS_CACHE_SERVICE_V2=1" >> .env
       - name: Run Runner
+        if: ${{ !env.ACT }}
         id: runner
         run: |
           RUNNER_RET=0

.yamllint.yml

@@ -0,0 +1,12 @@
+extends: default
+
+rules:
+  document-start: disable
+  truthy:
+    allowed-values: ['true', 'false']
+    check-keys: false
+  line-length:
+    max: 300
+    allow-non-breakable-words: true
+    allow-non-breakable-inline-mappings: true
+

config_riscv64.yaml

@@ -0,0 +1,52 @@
+---
+# RISC-V CI runner configuration
+#
+# Host platform: linux/amd64
+# Target platform: linux/riscv64 (emulated)
+#
+# Purpose:
+# - Enable RISC-V (riscv64) CI builds on x86_64 hosts
+# - Uses Docker + cross-compilation + QEMU (no native RISC-V hardware required)
+#
+# How it works:
+# - Runner executes inside an amd64 Docker container
+# - RISC-V binaries are cross-compiled using riscv64-linux-gnu toolchain
+# - Smoke tests are executed using qemu-riscv64
+#
+# Docker image:
+# - while1skothadiya/ffmpeg-riscv-docker:latest
+#   (contains toolchain, QEMU, and a statically-built FFmpeg)
+# - FFmpeg binary is statically linked to avoid runtime loader dependencies
+# Notes:
+# - This runner is NOT a native RISC-V environment
+# - Label "linux-riscv64" is logical and used for job routing only
+# - Privileged mode and host binfmt are intentionally avoided
+
+log:
+  level: info
+  job_level: info
+
+runner:
+  file: .runner
+  env_file: .env
+  capacity: 1
+  timeout: 3h
+  shutdown_timeout: 1h
+  insecure: false
+  fetch_timeout: 5s
+  labels:
+    - "linux-riscv64:docker://while1skothadiya/ffmpeg-riscv-docker:latest"
+
+cache:
+  enabled: true
+  dir: /var/actcache
+
+host:
+  workdir_parent: /var/act
+
+container:
+  network: "runnernet"
+  enable_ipv6: false
+  privileged: false
+  force_pull: true
+  force_rebuild: false

docs/ci-riscv64.md

@@ -0,0 +1,21 @@
+# RISC-V CI Support
+
+## Overview
+This project supports RISC-V (riscv64) builds using cross-compilation
+and QEMU emulation on x86_64 CI runners.
+
+## Architecture
+- Host: x86_64
+- Toolchain: riscv64-linux-gnu
+- Emulation: qemu-riscv64
+- Execution: Docker container
+
+## What this CI validates
+- Successful RISC-V compilation
+- Correct ELF architecture
+- Runtime smoke test via QEMU
+
+## What this CI does NOT do
+- Performance benchmarking
+- Native RISC-V validation
+

event.json

@@ -0,0 +1,9 @@
+{
+  "inputs": {
+    "x86_64_count": "0",
+    "riscv64_count": "1",
+    "aarch64_count": "0",
+    "win_x86_64_count": "0",
+    "osx_count": "0"
+  }
+}