Add v210 staging memory probe

AppConfig.cpp

@@ -15,6 +15,9 @@
 std::optional<PresentModeConfig> parsePresentMode(
     std::string_view text);
 
+std::optional<V210StagingMemoryMode> parseV210StagingMemoryMode(
+    std::string_view text);
+
 namespace
 {
 struct JsonValue
@@ -588,6 +591,20 @@ bool applyConfigFile(
         config.presentMode = mode.value();
     }
 
+    if (const std::string* memoryMode =
+            jsonString(objectField(*root, "v210StagingMemory")))
+    {
+        const std::optional<V210StagingMemoryMode> mode =
+            parseV210StagingMemoryMode(*memoryMode);
+        if (!mode.has_value())
+        {
+            error = "v210StagingMemory must be default, cached, "
+                    "or device-local";
+            return false;
+        }
+        config.v210StagingMemoryMode = mode.value();
+    }
+
     const JsonValue::Array* feeds =
         jsonArray(objectField(*root, "feeds"));
     if (feeds == nullptr)
@@ -721,6 +738,27 @@ std::optional<PresentModeConfig> parsePresentMode(std::string_view text)
     return std::nullopt;
 }
 
+std::optional<V210StagingMemoryMode> parseV210StagingMemoryMode(
+    std::string_view text)
+{
+    if (text == "default")
+    {
+        return V210StagingMemoryMode::Default;
+    }
+
+    if (text == "cached")
+    {
+        return V210StagingMemoryMode::Cached;
+    }
+
+    if (text == "device-local" || text == "device_local")
+    {
+        return V210StagingMemoryMode::DeviceLocal;
+    }
+
+    return std::nullopt;
+}
+
 std::string_view feedKindName(FeedKind kind)
 {
     switch (kind)
@@ -743,6 +781,23 @@ std::string_view feedKindName(FeedKind kind)
     }
 }
 
+std::string_view v210StagingMemoryModeName(
+    V210StagingMemoryMode mode)
+{
+    switch (mode)
+    {
+        case V210StagingMemoryMode::Cached:
+            return "cached";
+
+        case V210StagingMemoryMode::DeviceLocal:
+            return "device-local";
+
+        case V210StagingMemoryMode::Default:
+        default:
+            return "default";
+    }
+}
+
 void printUsage(const char* executableName)
 {
     std::cout
@@ -758,6 +813,7 @@ void printUsage(const char* executableName)
         << "  --grid <cols>x<rows>  Set multiview grid (default 2x2, max 16 feeds)\n"
         << "  --fps-cap <fps>       Limit render loop FPS (default 60)\n"
         << "  --max-v210-uploads <n> Limit v210 uploads per frame (0 = unlimited)\n"
+        << "  --v210-staging-memory <mode> Memory: default, cached, device-local\n"
         << "  --present <mode>      Present mode: fifo, mailbox, immediate (default mailbox)\n"
         << "  --feed <idx> <kind>   Set feed slot kind explicitly\n"
         << "  --domain <idx> <path> Set MXL domain for feed slot\n"
@@ -899,6 +955,36 @@ ConfigParseResult parseAppConfig(
             continue;
         }
 
+        if (arg == "--v210-staging-memory")
+        {
+            if (i + 1 >= argc)
+            {
+                std::cerr << "--v210-staging-memory requires <mode>"
+                          << std::endl;
+                result.shouldExit = true;
+                result.exitCode = 1;
+                return result;
+            }
+
+            const std::optional<V210StagingMemoryMode> mode =
+                parseV210StagingMemoryMode(argv[i + 1]);
+
+            if (!mode.has_value())
+            {
+                std::cerr
+                    << "--v210-staging-memory must be default, cached, "
+                    << "or device-local"
+                    << std::endl;
+                result.shouldExit = true;
+                result.exitCode = 1;
+                return result;
+            }
+
+            result.config.v210StagingMemoryMode = mode.value();
+            ++i;
+            continue;
+        }
+
         if (arg == "--grid")
         {
             ++i;