iadk: Define pass buffer size and return error code from entry point function

src/audio/module_adapter/iadk/system_agent.cpp

@@ -118,17 +118,15 @@ int SystemAgent::CheckIn(ProcessingModuleFactoryInterface& module_factory,
 } /* namespace system */
 } /* namespace intel_adsp */
 
-#ifdef __cplusplus
-extern "C" {
-#endif
 /* The create_instance_f is a function call type known in IADK module. The module entry_point
  * points to this type of function which starts module creation.
  */
 typedef int (*create_instance_f)(uint32_t module_id, uint32_t instance_id, uint32_t core_id,
 				 void *mod_cfg, void *parent_ppl, void **mod_ptr);
 
-void* system_agent_start(uint32_t entry_point, uint32_t module_id, uint32_t instance_id,
-			 uint32_t core_id, uint32_t log_handle, void* mod_cfg)
+int system_agent_start(uint32_t entry_point, uint32_t module_id, uint32_t instance_id,
+		       uint32_t core_id, uint32_t log_handle, void* mod_cfg,
+		       void **adapter)
 {
 	uint32_t ret;
 	SystemAgent system_agent(module_id, instance_id, core_id, log_handle);
@@ -137,13 +135,11 @@ void* system_agent_start(uint32_t entry_point, uint32_t module_id, uint32_t inst
 	create_instance_f ci = (create_instance_f)(entry_point);
 	ret = ci(module_id, instance_id, core_id, mod_cfg, NULL, &system_agent_p);
 
-	return system_agent_p;
+	IadkModuleAdapter* module_adapter = reinterpret_cast<IadkModuleAdapter*>(system_agent_p);
+	*adapter = module_adapter;
+	return ret;
 }
 
-#ifdef __cplusplus
-}
-#endif
-
 extern "C" void __cxa_pure_virtual()  __attribute__((weak));
 
 void __cxa_pure_virtual()

src/audio/module_adapter/module/modules.c

@@ -59,7 +59,8 @@ static int modules_init(struct processing_module *mod)
 	const struct comp_driver *const drv = dev->drv;
 	const struct ipc4_base_module_cfg *src_cfg = &md->cfg.base_cfg;
 	const struct comp_ipc_config *config = &dev->ipc_config;
-	void *system_agent;
+	void *adapter;
+	int ret;
 
 	uintptr_t module_entry_point = lib_manager_allocate_module(mod, config, src_cfg);
 
@@ -81,16 +82,20 @@ static int modules_init(struct processing_module *mod)
 		.size = md->cfg.size >> 2,
 	};
 
-	system_agent = system_agent_start(module_entry_point, module_id, instance_id, 0, log_handle,
-					  &mod_cfg);
+	ret = system_agent_start(module_entry_point, module_id, instance_id, 0, log_handle,
+				 &mod_cfg, &adapter);
+	if (ret) {
+		comp_info(dev, "System agent failed");
+		return ret;
+	}
 
-	module_set_private_data(mod, system_agent);
+	module_set_private_data(mod, adapter);
 
 	md->mpd.in_buff_size = src_cfg->ibs;
 	md->mpd.out_buff_size = src_cfg->obs;
 
 	mod->proc_type = MODULE_PROCESS_TYPE_SOURCE_SINK;
-	return iadk_wrapper_init(system_agent);
+	return iadk_wrapper_init(adapter);
 }
 
 /**

src/include/sof/audio/module_adapter/iadk/api_version.h

@@ -19,4 +19,10 @@
 #define IADK_MODULE_API_CURRENT_VERSION	MODULE_API_VERSION_ENCODE(IADK_MODULE_API_MAJOR_VERSION, \
 	IADK_MODULE_API_MIDDLE_VERSION, IADK_MODULE_API_MINOR_VERSION)
 
+/* Defines the size of the space reserved within ModuleHandle for SOF to store its private data.
+ * This size comes from the IADK header files and must match the IADK API version.
+ * Please do not modify this value!
+ */
+#define IADK_MODULE_PASS_BUFFER_SIZE		320
+
 #endif /* __MODULE_ADAPTER_IADK_API_VERSION_H__ */

src/include/sof/audio/module_adapter/iadk/iadk_module_adapter.h

@@ -15,6 +15,8 @@
 #include <module_initial_settings.h>
 #include <adsp_stddef.h>
 #include <system_error.h>
+#include <sof/common.h>
+#include <api_version.h>
 
 #ifdef __cplusplus
 extern "C" {
@@ -112,6 +114,8 @@ namespace dsp_fw
 		intel_adsp::ProcessingModuleInterface &processing_module_;
 	};
 
+STATIC_ASSERT(sizeof(IadkModuleAdapter) <= IADK_MODULE_PASS_BUFFER_SIZE, IadkModuleAdapter_too_big);
+
 } /* namespace dsp_fw */
 
 } /* extern "C" */

src/include/sof/audio/module_adapter/iadk/system_agent.h

@@ -72,8 +72,43 @@ namespace system
 #ifdef __cplusplus
 extern "C" {
 #endif
-void *system_agent_start(uint32_t entry_point, uint32_t module_id, uint32_t instance_id,
-			 uint32_t core_id, uint32_t log_handle, void *mod_cfg);
+/*
+ * The process of loading a IADK module is quite complicated. The function call stack is as follows:
+ *
+ *   1. IADK module adapter initialization function (modules_init) pass module entry point to the
+ *	system_agent_start function.
+ *
+ *   2. system_agent_start: This function creates an instance of the SystemAgent class on the stack
+ *	and then calls the module entry point function (ModuleEntryPoint) passing a pointer to the
+ *	SystemAgent object as a parameter.
+ *
+ *   3. ModuleEntryPoint(system_agent): Creates a ModuleFactory object of the module on the stack
+ *	(inheriting from ProcessingModuleFactoryInterface) and then calls the
+ *	LoadableModuleMain(system_agent, module_factory, placeholder) function, which is the default
+ *	entry point for all IADK modules. Placeholder is part of the .bss section intended for
+ *	a given module instance, with its address is determined based on the instance ID.
+ *
+ *   4. LoadableModuleMain(system_agent, module_factory, placeholder): Calls the CheckIn method
+ *	(variant with 7 parameters) of the SystemAgent class.
+ *
+ *   5. SystemAgent.CheckIn(7): Calls the Create method from the ModuleFactory object.
+ *
+ *   6. ModuleFactory.Create(system_agent, placeholder): Creates an instance of the module class
+ *	(inheriting from ProcessingModule) at the address pointed to by placeholder.
+ *	The ProcessingModule class contains a module_handle field, which reserves an area in memory
+ *	of size IADK_MODULE_PASS_BUFFER_SIZE bytes. The constructor of this class calls the CheckIn
+ *	method (the variant with 3 parameters) from the SystemAgent class, passing a pointer to self
+ *	and a pointer to module_handle.
+ *
+ *   7. SystemAgent.CheckIn(3): Stores the address of module_handle in a private variable and
+ *	creates an instance of the IadkModuleAdapter class in this location.
+ *
+ * The saved address of the module_handle (the adapter's IADK instance) is returned in the CheckIn
+ * method (the variant with 7 parameters) via a parameter that initially contained the address to
+ * the agent system. The system_agent_start function returns it in the variable adapter.
+ */
+int system_agent_start(uint32_t entry_point, uint32_t module_id, uint32_t instance_id,
+		       uint32_t core_id, uint32_t log_handle, void *mod_cfg, void **adapter);
 #ifdef __cplusplus
 }
 #endif