audio: codec_adapter: add llext support for dax

app/overlays/mtl/dax_overlay.conf

@@ -2,3 +2,10 @@ CONFIG_COMP_MODULE_ADAPTER=y
 CONFIG_COMP_DOLBY_DAX_AUDIO_PROCESSING=y
 CONFIG_COMP_DOLBY_DAX_AUDIO_PROCESSING_MOCK=n
 CONFIG_KCPS_DYNAMIC_CLOCK_CONTROL=n
+CONFIG_SOF_STACK_SIZE=8192
+
+# LLEXT
+CONFIG_LLEXT_HEAP_SIZE=32
+# Disabled due to issues encountered on the MTL platform.
+# See https://github.com/thesofproject/sof/issues/10370
+CONFIG_LLEXT_EXPERIMENTAL=n

src/audio/module_adapter/CMakeLists.txt

@@ -26,17 +26,24 @@ if(zephyr) ###  Zephyr ###
 	endif()
 
 	if (CONFIG_COMP_DOLBY_DAX_AUDIO_PROCESSING)
-		zephyr_library_sources(
-			module/dolby/dax.c
-		)
-		if (CONFIG_COMP_DOLBY_DAX_AUDIO_PROCESSING_MOCK)
+		if(CONFIG_COMP_DOLBY_DAX_AUDIO_PROCESSING STREQUAL "m" AND DEFINED CONFIG_LLEXT)
+			add_subdirectory(module/dolby/llext
+					 ${PROJECT_BINARY_DIR}/dolby_dax_audio_processing_llext)
+			add_dependencies(app dolby_dax_audio_processing)
+		else()
 			zephyr_library_sources(
-				module/dolby/dax_mock.c
+				module/dolby/dax.c
 			)
-		else()
-			target_link_libraries(SOF INTERFACE m)
-			target_link_libraries(SOF INTERFACE c)
-			zephyr_library_import(dax_effect ${sof_top_dir}/third_party/lib/libdax.a)
+			if (CONFIG_COMP_DOLBY_DAX_AUDIO_PROCESSING_MOCK)
+				zephyr_library_sources(
+					module/dolby/dax_mock.c
+				)
+			else()
+				target_link_libraries(SOF INTERFACE m)
+				target_link_libraries(SOF INTERFACE c)
+				zephyr_library_import(dax_effect
+						      ${sof_top_dir}/third_party/lib/libdax.a)
+			endif()
 		endif()
 	endif()
 

src/audio/module_adapter/Kconfig

@@ -176,8 +176,7 @@ if CADENCE_CODEC
 endif # Cadence
 
 	config COMP_DOLBY_DAX_AUDIO_PROCESSING
-		bool "Dolby DAX audio processing component"
-		default n
+		tristate "Dolby DAX audio processing component"
 		help
 		  Select to include Dolby DAX component. Dolby DAX component implements DAX API.
 		  API definition together with pre-compiled library is shared by Dolby.

src/audio/module_adapter/module/dolby/dax.c

@@ -814,7 +814,34 @@ static const struct module_interface dolby_dax_audio_processing_interface = {
 	.free = sof_dax_free,
 };
 
+#if CONFIG_COMP_DOLBY_DAX_AUDIO_PROCESSING_MODULE
+/* modular: llext dynamic link */
+
+#include <module/module/api_ver.h>
+#include <module/module/llext.h>
+#include <rimage/sof/user/manifest.h>
+
+static const struct sof_man_module_manifest main_manifest __section(".module") __used = {
+	.module = {
+		.name = "DAX",
+		.uuid = SOF_REG_UUID(dolby_dax_audio_processing),
+		.entry_point = (uint32_t)(&dolby_dax_audio_processing_interface),
+		.instance_max_count = 1,
+		.type = {
+			.load_type = SOF_MAN_MOD_TYPE_LLEXT,
+			.domain_dp = 1,
+		},
+		.affinity_mask = 7,
+	}
+};
+
+SOF_LLEXT_BUILDINFO;
+
+#else
+
 DECLARE_MODULE_ADAPTER(dolby_dax_audio_processing_interface, dolby_dax_audio_processing_uuid,
 		       dolby_dax_audio_processing_tr);
 SOF_MODULE_INIT(dolby_dax_audio_processing,
 		sys_comp_module_dolby_dax_audio_processing_interface_init);
+
+#endif

src/audio/module_adapter/module/dolby/llext-wrap.c

@@ -0,0 +1,75 @@
+// SPDX-License-Identifier: BSD-3-Clause
+//
+// Copyright(c) 2025 Intel Corporation. All rights reserved.
+
+#include <stdint.h>
+#include <errno.h>
+#include <assert.h>
+#include <rtos/symbol.h>
+
+/*
+ * Stubs that are needed for linkage of some applications or libraries
+ * that come from porting userspace code. Anyone porting should
+ * make sure that any code does not depend on working copies of these
+ * reentrant functions. We will fail for any caller.
+ */
+
+struct stat;
+struct _reent;
+
+size_t _read_r(struct _reent *ptr, int fd, char *buf, size_t cnt)
+{
+	errno = -ENOTSUP;
+	return -ENOTSUP;
+}
+
+size_t _write_r(struct _reent *ptr, int fd, char *buf, size_t cnt)
+{
+	errno = -ENOTSUP;
+	return -ENOTSUP;
+}
+
+void *_sbrk_r(struct _reent *ptr, ptrdiff_t incr)
+{
+	errno = -ENOTSUP;
+	return NULL;
+}
+
+int _lseek_r(struct _reent *ptr, int fd, int pos, int whence)
+{
+	errno = -ENOTSUP;
+	return -ENOTSUP;
+}
+
+int _kill_r(struct _reent *ptr, int pid, int sig)
+{
+	errno = -ENOTSUP;
+	return -ENOTSUP;
+}
+
+int _getpid_r(struct _reent *ptr)
+{
+	errno = -ENOTSUP;
+	return -ENOTSUP;
+}
+
+int _fstat_r(struct _reent *ptr, int fd, struct stat *pstat)
+{
+	errno = -ENOTSUP;
+	return -ENOTSUP;
+}
+
+int _close_r(struct _reent *ptr, int fd)
+{
+	errno = -ENOTSUP;
+	return -ENOTSUP;
+}
+
+void _exit(int status)
+{
+	assert(0);
+	while (1) {
+		/* spin forever */
+	}
+	/* NOTREACHED */
+}

src/audio/module_adapter/module/dolby/llext/CMakeLists.txt

@@ -0,0 +1,17 @@
+# Copyright(c) 2025 Dolby Laboratories.
+# SPDX-License-Identifier: Apache-2.0
+
+if(CONFIG_COMP_DOLBY_DAX_AUDIO_PROCESSING_MOCK)
+	sof_llext_build("dolby_dax_audio_processing"
+		SOURCES ../dax.c
+			../dax_mock.c
+		INCLUDES ${sof_top_dir}/third_party/include
+	)
+else()
+	sof_llext_build("dolby_dax_audio_processing"
+		SOURCES ../dax.c ../llext-wrap.c
+		INCLUDES ${sof_top_dir}/third_party/include
+		LIBS_PATH ${sof_top_dir}/third_party/lib/
+		LIBS dax m c gcc
+	)
+endif()

src/audio/module_adapter/module/dolby/llext/llext.toml.h

@@ -0,0 +1,10 @@
+/* SPDX-License-Identifier: BSD-3-Clause
+ *
+ * Copyright(c) 2025 Dolby Laboratories. All rights reserved.
+ */
+#include <tools/rimage/config/platform.toml>
+#define LOAD_TYPE "2"
+#include "../dax.toml"
+
+[module]
+count = __COUNTER__