Merge branch 'acpi-debug'

* acpi-debug:
  ACPI / debugger: Fix a redundant mutex unlock issue in acpi_aml_open()
  ACPI / debugger: copy_to_user doesn't return errors
  ACPI / debugger: remove some unneeded conditions
  ACPI / debugger: Fix an issue a flag is modified without locking
  ACPI / debugger: Add module support for ACPI debugger
  tools/power/acpi: Add userspace AML interface support
  ACPI / debugger: Add IO interface to access debugger functionalities
  ACPICA: Debugger: Fix runtime stub issues of ACPI_DEBUGGER_EXEC using different stub mechanism
  ACPICA: Debugger: Convert some mechanisms to OSPM specific
  ACPICA: Debugger: Remove unnecessary status check

drivers/acpi/Kconfig

@@ -58,14 +58,25 @@ config ACPI_CCA_REQUIRED
 	bool
 
 config ACPI_DEBUGGER
-	bool "AML debugger interface (EXPERIMENTAL)"
+	bool "AML debugger interface"
 	select ACPI_DEBUG
 	help
-	  Enable in-kernel debugging of AML facilities: statistics, internal
-	  object dump, single step control method execution.
+	  Enable in-kernel debugging of AML facilities: statistics,
+	  internal object dump, single step control method execution.
 	  This is still under development, currently enabling this only
 	  results in the compilation of the ACPICA debugger files.
 
+if ACPI_DEBUGGER
+
+config ACPI_DEBUGGER_USER
+	tristate "Userspace debugger accessiblity"
+	depends on DEBUG_FS
+	help
+	  Export /sys/kernel/debug/acpi/acpidbg for userspace utilities
+	  to access the debugger functionalities.
+
+endif
+
 config ACPI_SLEEP
 	bool
 	depends on SUSPEND || HIBERNATION

drivers/acpi/Makefile

@@ -79,6 +79,7 @@ obj-$(CONFIG_ACPI_EC_DEBUGFS)	+= ec_sys.o
 obj-$(CONFIG_ACPI_CUSTOM_METHOD)+= custom_method.o
 obj-$(CONFIG_ACPI_BGRT)		+= bgrt.o
 obj-$(CONFIG_ACPI_CPPC_LIB)	+= cppc_acpi.o
+obj-$(CONFIG_ACPI_DEBUGGER_USER) += acpi_dbg.o
 
 # processor has its own "processor." module_param namespace
 processor-y			:= processor_driver.o

drivers/acpi/acpica/acdebug.h

@@ -80,9 +80,15 @@ struct acpi_db_execute_walk {
 /*
  * dbxface - external debugger interfaces
  */
-acpi_status
-acpi_db_single_step(struct acpi_walk_state *walk_state,
-		    union acpi_parse_object *op, u32 op_type);
+ACPI_DBR_DEPENDENT_RETURN_OK(acpi_status
+			     acpi_db_single_step(struct acpi_walk_state
+						 *walk_state,
+						 union acpi_parse_object *op,
+						 u32 op_type))
+ ACPI_DBR_DEPENDENT_RETURN_VOID(void
+				acpi_db_signal_break_point(struct
+							   acpi_walk_state
+							   *walk_state))
 
 /*
  * dbcmds - debug commands and output routines
@@ -182,11 +188,15 @@ void acpi_db_display_method_info(union acpi_parse_object *op);
 
 void acpi_db_decode_and_display_object(char *target, char *output_type);
 
-void
-acpi_db_display_result_object(union acpi_operand_object *obj_desc,
-			      struct acpi_walk_state *walk_state);
+ACPI_DBR_DEPENDENT_RETURN_VOID(void
+			       acpi_db_display_result_object(union
+							     acpi_operand_object
+							     *obj_desc,
+							     struct
+							     acpi_walk_state
+							     *walk_state))
 
-acpi_status acpi_db_display_all_methods(char *display_count_arg);
+ acpi_status acpi_db_display_all_methods(char *display_count_arg);
 
 void acpi_db_display_arguments(void);
 
@@ -198,9 +208,13 @@ void acpi_db_display_calling_tree(void);
 
 void acpi_db_display_object_type(char *object_arg);
 
-void
-acpi_db_display_argument_object(union acpi_operand_object *obj_desc,
-				struct acpi_walk_state *walk_state);
+ACPI_DBR_DEPENDENT_RETURN_VOID(void
+			       acpi_db_display_argument_object(union
+							       acpi_operand_object
+							       *obj_desc,
+							       struct
+							       acpi_walk_state
+							       *walk_state))
 
 /*
  * dbexec - debugger control method execution
@@ -257,7 +271,7 @@ acpi_db_command_dispatch(char *input_buffer,
 
 void ACPI_SYSTEM_XFACE acpi_db_execute_thread(void *context);
 
-acpi_status acpi_db_user_commands(char prompt, union acpi_parse_object *op);
+acpi_status acpi_db_user_commands(void);
 
 char *acpi_db_get_next_token(char *string,
 			     char **next, acpi_object_type * return_type);

drivers/acpi/acpica/acglobal.h

@@ -326,7 +326,6 @@ ACPI_GLOBAL(struct acpi_external_file *, acpi_gbl_external_file_list);
 #ifdef ACPI_DEBUGGER
 
 ACPI_INIT_GLOBAL(u8, acpi_gbl_abort_method, FALSE);
-ACPI_INIT_GLOBAL(u8, acpi_gbl_method_executing, FALSE);
 ACPI_INIT_GLOBAL(acpi_thread_id, acpi_gbl_db_thread_id, ACPI_INVALID_THREAD_ID);
 
 ACPI_GLOBAL(u8, acpi_gbl_db_opt_no_ini_methods);
@@ -345,7 +344,6 @@ ACPI_GLOBAL(acpi_object_type, acpi_gbl_db_arg_types[ACPI_DEBUGGER_MAX_ARGS]);
 
 /* These buffers should all be the same size */
 
-ACPI_GLOBAL(char, acpi_gbl_db_line_buf[ACPI_DB_LINE_BUFFER_SIZE]);
 ACPI_GLOBAL(char, acpi_gbl_db_parsed_buf[ACPI_DB_LINE_BUFFER_SIZE]);
 ACPI_GLOBAL(char, acpi_gbl_db_scope_buf[ACPI_DB_LINE_BUFFER_SIZE]);
 ACPI_GLOBAL(char, acpi_gbl_db_debug_filename[ACPI_DB_LINE_BUFFER_SIZE]);
@@ -360,9 +358,6 @@ ACPI_GLOBAL(u16, acpi_gbl_node_type_count_misc);
 ACPI_GLOBAL(u32, acpi_gbl_num_nodes);
 ACPI_GLOBAL(u32, acpi_gbl_num_objects);
 
-ACPI_GLOBAL(acpi_mutex, acpi_gbl_db_command_ready);
-ACPI_GLOBAL(acpi_mutex, acpi_gbl_db_command_complete);
-
 #endif				/* ACPI_DEBUGGER */
 
 /*****************************************************************************

drivers/acpi/acpica/acmacros.h

@@ -400,17 +400,6 @@
 #define ACPI_HW_OPTIONAL_FUNCTION(addr)     NULL
 #endif
 
-/*
- * Some code only gets executed when the debugger is built in.
- * Note that this is entirely independent of whether the
- * DEBUG_PRINT stuff (set by ACPI_DEBUG_OUTPUT) is on, or not.
- */
-#ifdef ACPI_DEBUGGER
-#define ACPI_DEBUGGER_EXEC(a)           a
-#else
-#define ACPI_DEBUGGER_EXEC(a)
-#endif
-
 /*
  * Macros used for ACPICA utilities only
  */

drivers/acpi/acpica/dbdisply.c

@@ -679,6 +679,12 @@ acpi_db_display_result_object(union acpi_operand_object *obj_desc,
 			      struct acpi_walk_state *walk_state)
 {
 
+#ifndef ACPI_APPLICATION
+	if (acpi_gbl_db_thread_id != acpi_os_get_thread_id()) {
+		return;
+	}
+#endif
+
 	/* Only display if single stepping */
 
 	if (!acpi_gbl_cm_single_step) {
@@ -708,6 +714,12 @@ acpi_db_display_argument_object(union acpi_operand_object *obj_desc,
 				struct acpi_walk_state *walk_state)
 {
 
+#ifndef ACPI_APPLICATION
+	if (acpi_gbl_db_thread_id != acpi_os_get_thread_id()) {
+		return;
+	}
+#endif
+
 	if (!acpi_gbl_cm_single_step) {
 		return;
 	}

drivers/acpi/acpica/dbinput.c

@@ -53,8 +53,6 @@ static u32 acpi_db_get_line(char *input_buffer);
 
 static u32 acpi_db_match_command(char *user_command);
 
-static void acpi_db_single_thread(void);
-
 static void acpi_db_display_command_info(char *command, u8 display_all);
 
 static void acpi_db_display_help(char *command);
@@ -1149,55 +1147,16 @@ acpi_db_command_dispatch(char *input_buffer,
 
 void ACPI_SYSTEM_XFACE acpi_db_execute_thread(void *context)
 {
-	acpi_status status = AE_OK;
-	acpi_status Mstatus;
-
-	while (status != AE_CTRL_TERMINATE && !acpi_gbl_db_terminate_loop) {
-		acpi_gbl_method_executing = FALSE;
-		acpi_gbl_step_to_next_call = FALSE;
-
-		Mstatus = acpi_os_acquire_mutex(acpi_gbl_db_command_ready,
-						ACPI_WAIT_FOREVER);
-		if (ACPI_FAILURE(Mstatus)) {
-			return;
-		}
-
-		status =
-		    acpi_db_command_dispatch(acpi_gbl_db_line_buf, NULL, NULL);
 
-		acpi_os_release_mutex(acpi_gbl_db_command_complete);
-	}
+	(void)acpi_db_user_commands();
 	acpi_gbl_db_threads_terminated = TRUE;
 }
 
-/*******************************************************************************
- *
- * FUNCTION:    acpi_db_single_thread
- *
- * PARAMETERS:  None
- *
- * RETURN:      None
- *
- * DESCRIPTION: Debugger execute thread. Waits for a command line, then
- *              simply dispatches it.
- *
- ******************************************************************************/
-
-static void acpi_db_single_thread(void)
-{
-
-	acpi_gbl_method_executing = FALSE;
-	acpi_gbl_step_to_next_call = FALSE;
-
-	(void)acpi_db_command_dispatch(acpi_gbl_db_line_buf, NULL, NULL);
-}
-
 /*******************************************************************************
  *
  * FUNCTION:    acpi_db_user_commands
  *
- * PARAMETERS:  prompt              - User prompt (depends on mode)
- *              op                  - Current executing parse op
+ * PARAMETERS:  None
  *
  * RETURN:      None
  *
@@ -1206,7 +1165,7 @@ static void acpi_db_single_thread(void)
  *
  ******************************************************************************/
 
-acpi_status acpi_db_user_commands(char prompt, union acpi_parse_object *op)
+acpi_status acpi_db_user_commands(void)
 {
 	acpi_status status = AE_OK;
 
@@ -1216,52 +1175,31 @@ acpi_status acpi_db_user_commands(char prompt, union acpi_parse_object *op)
 
 	while (!acpi_gbl_db_terminate_loop) {
 
-		/* Force output to console until a command is entered */
-
-		acpi_db_set_output_destination(ACPI_DB_CONSOLE_OUTPUT);
-
-		/* Different prompt if method is executing */
-
-		if (!acpi_gbl_method_executing) {
-			acpi_os_printf("%1c ", ACPI_DEBUGGER_COMMAND_PROMPT);
-		} else {
-			acpi_os_printf("%1c ", ACPI_DEBUGGER_EXECUTE_PROMPT);
-		}
-
-		/* Get the user input line */
+		/* Wait the readiness of the command */
 
-		status = acpi_os_get_line(acpi_gbl_db_line_buf,
-					  ACPI_DB_LINE_BUFFER_SIZE, NULL);
+		status = acpi_os_wait_command_ready();
 		if (ACPI_FAILURE(status)) {
-			ACPI_EXCEPTION((AE_INFO, status,
-					"While parsing command line"));
-			return (status);
+			break;
 		}
 
-		/* Check for single or multithreaded debug */
+		/* Just call to the command line interpreter */
 
-		if (acpi_gbl_debugger_configuration & DEBUGGER_MULTI_THREADED) {
-			/*
-			 * Signal the debug thread that we have a command to execute,
-			 * and wait for the command to complete.
-			 */
-			acpi_os_release_mutex(acpi_gbl_db_command_ready);
-			if (ACPI_FAILURE(status)) {
-				return (status);
-			}
+		acpi_gbl_method_executing = FALSE;
+		acpi_gbl_step_to_next_call = FALSE;
 
-			status =
-			    acpi_os_acquire_mutex(acpi_gbl_db_command_complete,
-						  ACPI_WAIT_FOREVER);
-			if (ACPI_FAILURE(status)) {
-				return (status);
-			}
-		} else {
-			/* Just call to the command line interpreter */
+		(void)acpi_db_command_dispatch(acpi_gbl_db_line_buf, NULL,
+					       NULL);
+
+		/* Notify the completion of the command */
 
-			acpi_db_single_thread();
+		status = acpi_os_notify_command_complete();
+		if (ACPI_FAILURE(status)) {
+			break;
 		}
 	}
 
+	if (ACPI_FAILURE(status) && status != AE_CTRL_TERMINATE) {
+		ACPI_EXCEPTION((AE_INFO, status, "While parsing command line"));
+	}
 	return (status);
 }

drivers/acpi/acpica/dbxface.c

@@ -85,46 +85,21 @@ acpi_db_start_command(struct acpi_walk_state *walk_state,
 
 	acpi_gbl_method_executing = TRUE;
 	status = AE_CTRL_TRUE;
-	while (status == AE_CTRL_TRUE) {
-		if (acpi_gbl_debugger_configuration == DEBUGGER_MULTI_THREADED) {
-
-			/* Handshake with the front-end that gets user command lines */
-
-			acpi_os_release_mutex(acpi_gbl_db_command_complete);
-
-			status =
-			    acpi_os_acquire_mutex(acpi_gbl_db_command_ready,
-						  ACPI_WAIT_FOREVER);
-			if (ACPI_FAILURE(status)) {
-				return (status);
-			}
-		} else {
-			/* Single threaded, we must get a command line ourselves */
-
-			/* Force output to console until a command is entered */
 
-			acpi_db_set_output_destination(ACPI_DB_CONSOLE_OUTPUT);
+	while (status == AE_CTRL_TRUE) {
 
-			/* Different prompt if method is executing */
+		/* Notify the completion of the command */
 
-			if (!acpi_gbl_method_executing) {
-				acpi_os_printf("%1c ",
-					       ACPI_DEBUGGER_COMMAND_PROMPT);
-			} else {
-				acpi_os_printf("%1c ",
-					       ACPI_DEBUGGER_EXECUTE_PROMPT);
-			}
+		status = acpi_os_notify_command_complete();
+		if (ACPI_FAILURE(status)) {
+			goto error_exit;
+		}
 
-			/* Get the user input line */
+		/* Wait the readiness of the command */
 
-			status = acpi_os_get_line(acpi_gbl_db_line_buf,
-						  ACPI_DB_LINE_BUFFER_SIZE,
-						  NULL);
-			if (ACPI_FAILURE(status)) {
-				ACPI_EXCEPTION((AE_INFO, status,
-						"While parsing command line"));
-				return (status);
-			}
+		status = acpi_os_wait_command_ready();
+		if (ACPI_FAILURE(status)) {
+			goto error_exit;
 		}
 
 		status =
@@ -134,9 +109,44 @@ acpi_db_start_command(struct acpi_walk_state *walk_state,
 
 	/* acpi_ut_acquire_mutex (ACPI_MTX_NAMESPACE); */
 
+error_exit:
+	if (ACPI_FAILURE(status) && status != AE_CTRL_TERMINATE) {
+		ACPI_EXCEPTION((AE_INFO, status,
+				"While parsing/handling command line"));
+	}
 	return (status);
 }
 
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_db_signal_break_point
+ *
+ * PARAMETERS:  walk_state      - Current walk
+ *
+ * RETURN:      Status
+ *
+ * DESCRIPTION: Called for AML_BREAK_POINT_OP
+ *
+ ******************************************************************************/
+
+void acpi_db_signal_break_point(struct acpi_walk_state *walk_state)
+{
+
+#ifndef ACPI_APPLICATION
+	if (acpi_gbl_db_thread_id != acpi_os_get_thread_id()) {
+		return;
+	}
+#endif
+
+	/*
+	 * Set the single-step flag. This will cause the debugger (if present)
+	 * to break to the console within the AML debugger at the start of the
+	 * next AML instruction.
+	 */
+	acpi_gbl_cm_single_step = TRUE;
+	acpi_os_printf("**break** Executed AML BreakPoint opcode\n");
+}
+
 /*******************************************************************************
  *
  * FUNCTION:    acpi_db_single_step
@@ -420,15 +430,7 @@ acpi_status acpi_initialize_debugger(void)
 
 		/* These were created with one unit, grab it */
 
-		status = acpi_os_acquire_mutex(acpi_gbl_db_command_complete,
-					       ACPI_WAIT_FOREVER);
-		if (ACPI_FAILURE(status)) {
-			acpi_os_printf("Could not get debugger mutex\n");
-			return_ACPI_STATUS(status);
-		}
-
-		status = acpi_os_acquire_mutex(acpi_gbl_db_command_ready,
-					       ACPI_WAIT_FOREVER);
+		status = acpi_os_initialize_command_signals();
 		if (ACPI_FAILURE(status)) {
 			acpi_os_printf("Could not get debugger mutex\n");
 			return_ACPI_STATUS(status);
@@ -473,13 +475,14 @@ void acpi_terminate_debugger(void)
 	acpi_gbl_db_terminate_loop = TRUE;
 
 	if (acpi_gbl_debugger_configuration & DEBUGGER_MULTI_THREADED) {
-		acpi_os_release_mutex(acpi_gbl_db_command_ready);
 
 		/* Wait the AML Debugger threads */
 
 		while (!acpi_gbl_db_threads_terminated) {
 			acpi_os_sleep(100);
 		}
+
+		acpi_os_terminate_command_signals();
 	}
 
 	if (acpi_gbl_db_buffer) {

drivers/acpi/acpica/dscontrol.c

@@ -47,6 +47,7 @@
 #include "amlcode.h"
 #include "acdispat.h"
 #include "acinterp.h"
+#include "acdebug.h"
 
 #define _COMPONENT          ACPI_DISPATCHER
 ACPI_MODULE_NAME("dscontrol")
@@ -348,14 +349,7 @@ acpi_ds_exec_end_control_op(struct acpi_walk_state * walk_state,
 
 	case AML_BREAK_POINT_OP:
 
-		/*
-		 * Set the single-step flag. This will cause the debugger (if present)
-		 * to break to the console within the AML debugger at the start of the
-		 * next AML instruction.
-		 */
-		ACPI_DEBUGGER_EXEC(acpi_gbl_cm_single_step = TRUE);
-		ACPI_DEBUGGER_EXEC(acpi_os_printf
-				   ("**break** Executed AML BreakPoint opcode\n"));
+		acpi_db_signal_break_point(walk_state);
 
 		/* Call to the OSL in case OS wants a piece of the action */
 

drivers/acpi/acpica/dsutils.c

@@ -605,8 +605,8 @@ acpi_ds_create_operand(struct acpi_walk_state *walk_state,
 		if (ACPI_FAILURE(status)) {
 			return_ACPI_STATUS(status);
 		}
-		ACPI_DEBUGGER_EXEC(acpi_db_display_argument_object
-				   (obj_desc, walk_state));
+
+		acpi_db_display_argument_object(obj_desc, walk_state);
 	} else {
 		/* Check for null name case */
 
@@ -638,10 +638,11 @@ acpi_ds_create_operand(struct acpi_walk_state *walk_state,
 			ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
 					  "Argument previously created, already stacked\n"));
 
-			ACPI_DEBUGGER_EXEC(acpi_db_display_argument_object
-					   (walk_state->
-					    operands[walk_state->num_operands -
-						     1], walk_state));
+			acpi_db_display_argument_object(walk_state->
+							operands[walk_state->
+								 num_operands -
+								 1],
+							walk_state);
 
 			/*
 			 * Use value that was already previously returned
@@ -685,8 +686,7 @@ acpi_ds_create_operand(struct acpi_walk_state *walk_state,
 			return_ACPI_STATUS(status);
 		}
 
-		ACPI_DEBUGGER_EXEC(acpi_db_display_argument_object
-				   (obj_desc, walk_state));
+		acpi_db_display_argument_object(obj_desc, walk_state);
 	}
 
 	return_ACPI_STATUS(AE_OK);

drivers/acpi/acpica/dswexec.c

@@ -178,8 +178,7 @@ acpi_ds_get_predicate_value(struct acpi_walk_state *walk_state,
 
 	/* Break to debugger to display result */
 
-	ACPI_DEBUGGER_EXEC(acpi_db_display_result_object
-			   (local_obj_desc, walk_state));
+	acpi_db_display_result_object(local_obj_desc, walk_state);
 
 	/*
 	 * Delete the predicate result object (we know that
@@ -386,11 +385,10 @@ acpi_status acpi_ds_exec_end_op(struct acpi_walk_state *walk_state)
 
 	/* Call debugger for single step support (DEBUG build only) */
 
-	ACPI_DEBUGGER_EXEC(status =
-			   acpi_db_single_step(walk_state, op, op_class));
-	ACPI_DEBUGGER_EXEC(if (ACPI_FAILURE(status)) {
-			   return_ACPI_STATUS(status);}
-	) ;
+	status = acpi_db_single_step(walk_state, op, op_class);
+	if (ACPI_FAILURE(status)) {
+		return_ACPI_STATUS(status);
+	}
 
 	/* Decode the Opcode Class */
 
@@ -728,8 +726,8 @@ acpi_status acpi_ds_exec_end_op(struct acpi_walk_state *walk_state)
 
 		/* Break to debugger to display result */
 
-		ACPI_DEBUGGER_EXEC(acpi_db_display_result_object
-				   (walk_state->result_obj, walk_state));
+		acpi_db_display_result_object(walk_state->result_obj,
+					      walk_state);
 
 		/*
 		 * Delete the result op if and only if:

drivers/acpi/acpica/utmutex.c

@@ -111,17 +111,6 @@ acpi_status acpi_ut_mutex_initialize(void)
 	if (ACPI_FAILURE(status)) {
 		return_ACPI_STATUS(status);
 	}
-#ifdef ACPI_DEBUGGER
-
-	/* Debugger Support */
-
-	status = acpi_os_create_mutex(&acpi_gbl_db_command_ready);
-	if (ACPI_FAILURE(status)) {
-		return_ACPI_STATUS(status);
-	}
-
-	status = acpi_os_create_mutex(&acpi_gbl_db_command_complete);
-#endif
 
 	return_ACPI_STATUS(status);
 }
@@ -162,12 +151,6 @@ void acpi_ut_mutex_terminate(void)
 	/* Delete the reader/writer lock */
 
 	acpi_ut_delete_rw_lock(&acpi_gbl_namespace_rw_lock);
-
-#ifdef ACPI_DEBUGGER
-	acpi_os_delete_mutex(acpi_gbl_db_command_ready);
-	acpi_os_delete_mutex(acpi_gbl_db_command_complete);
-#endif
-
 	return_VOID;
 }
 

drivers/acpi/bus.c

@@ -1094,6 +1094,7 @@ static int __init acpi_init(void)
 	acpi_debugfs_init();
 	acpi_sleep_proc_init();
 	acpi_wakeup_device_init();
+	acpi_debugger_init();
 	return 0;
 }
 

drivers/acpi/osl.c

@@ -220,6 +220,7 @@ void acpi_os_printf(const char *fmt, ...)
 	acpi_os_vprintf(fmt, args);
 	va_end(args);
 }
+EXPORT_SYMBOL(acpi_os_printf);
 
 void acpi_os_vprintf(const char *fmt, va_list args)
 {
@@ -234,7 +235,8 @@ void acpi_os_vprintf(const char *fmt, va_list args)
 		printk(KERN_CONT "%s", buffer);
 	}
 #else
-	printk(KERN_CONT "%s", buffer);
+	if (acpi_debugger_write_log(buffer) < 0)
+		printk(KERN_CONT "%s", buffer);
 #endif
 }
 
@@ -1101,6 +1103,200 @@ static void acpi_os_execute_deferred(struct work_struct *work)
 	kfree(dpc);
 }
 
+#ifdef CONFIG_ACPI_DEBUGGER
+static struct acpi_debugger acpi_debugger;
+static bool acpi_debugger_initialized;
+
+int acpi_register_debugger(struct module *owner,
+			   const struct acpi_debugger_ops *ops)
+{
+	int ret = 0;
+
+	mutex_lock(&acpi_debugger.lock);
+	if (acpi_debugger.ops) {
+		ret = -EBUSY;
+		goto err_lock;
+	}
+
+	acpi_debugger.owner = owner;
+	acpi_debugger.ops = ops;
+
+err_lock:
+	mutex_unlock(&acpi_debugger.lock);
+	return ret;
+}
+EXPORT_SYMBOL(acpi_register_debugger);
+
+void acpi_unregister_debugger(const struct acpi_debugger_ops *ops)
+{
+	mutex_lock(&acpi_debugger.lock);
+	if (ops == acpi_debugger.ops) {
+		acpi_debugger.ops = NULL;
+		acpi_debugger.owner = NULL;
+	}
+	mutex_unlock(&acpi_debugger.lock);
+}
+EXPORT_SYMBOL(acpi_unregister_debugger);
+
+int acpi_debugger_create_thread(acpi_osd_exec_callback function, void *context)
+{
+	int ret;
+	int (*func)(acpi_osd_exec_callback, void *);
+	struct module *owner;
+
+	if (!acpi_debugger_initialized)
+		return -ENODEV;
+	mutex_lock(&acpi_debugger.lock);
+	if (!acpi_debugger.ops) {
+		ret = -ENODEV;
+		goto err_lock;
+	}
+	if (!try_module_get(acpi_debugger.owner)) {
+		ret = -ENODEV;
+		goto err_lock;
+	}
+	func = acpi_debugger.ops->create_thread;
+	owner = acpi_debugger.owner;
+	mutex_unlock(&acpi_debugger.lock);
+
+	ret = func(function, context);
+
+	mutex_lock(&acpi_debugger.lock);
+	module_put(owner);
+err_lock:
+	mutex_unlock(&acpi_debugger.lock);
+	return ret;
+}
+
+ssize_t acpi_debugger_write_log(const char *msg)
+{
+	ssize_t ret;
+	ssize_t (*func)(const char *);
+	struct module *owner;
+
+	if (!acpi_debugger_initialized)
+		return -ENODEV;
+	mutex_lock(&acpi_debugger.lock);
+	if (!acpi_debugger.ops) {
+		ret = -ENODEV;
+		goto err_lock;
+	}
+	if (!try_module_get(acpi_debugger.owner)) {
+		ret = -ENODEV;
+		goto err_lock;
+	}
+	func = acpi_debugger.ops->write_log;
+	owner = acpi_debugger.owner;
+	mutex_unlock(&acpi_debugger.lock);
+
+	ret = func(msg);
+
+	mutex_lock(&acpi_debugger.lock);
+	module_put(owner);
+err_lock:
+	mutex_unlock(&acpi_debugger.lock);
+	return ret;
+}
+
+ssize_t acpi_debugger_read_cmd(char *buffer, size_t buffer_length)
+{
+	ssize_t ret;
+	ssize_t (*func)(char *, size_t);
+	struct module *owner;
+
+	if (!acpi_debugger_initialized)
+		return -ENODEV;
+	mutex_lock(&acpi_debugger.lock);
+	if (!acpi_debugger.ops) {
+		ret = -ENODEV;
+		goto err_lock;
+	}
+	if (!try_module_get(acpi_debugger.owner)) {
+		ret = -ENODEV;
+		goto err_lock;
+	}
+	func = acpi_debugger.ops->read_cmd;
+	owner = acpi_debugger.owner;
+	mutex_unlock(&acpi_debugger.lock);
+
+	ret = func(buffer, buffer_length);
+
+	mutex_lock(&acpi_debugger.lock);
+	module_put(owner);
+err_lock:
+	mutex_unlock(&acpi_debugger.lock);
+	return ret;
+}
+
+int acpi_debugger_wait_command_ready(void)
+{
+	int ret;
+	int (*func)(bool, char *, size_t);
+	struct module *owner;
+
+	if (!acpi_debugger_initialized)
+		return -ENODEV;
+	mutex_lock(&acpi_debugger.lock);
+	if (!acpi_debugger.ops) {
+		ret = -ENODEV;
+		goto err_lock;
+	}
+	if (!try_module_get(acpi_debugger.owner)) {
+		ret = -ENODEV;
+		goto err_lock;
+	}
+	func = acpi_debugger.ops->wait_command_ready;
+	owner = acpi_debugger.owner;
+	mutex_unlock(&acpi_debugger.lock);
+
+	ret = func(acpi_gbl_method_executing,
+		   acpi_gbl_db_line_buf, ACPI_DB_LINE_BUFFER_SIZE);
+
+	mutex_lock(&acpi_debugger.lock);
+	module_put(owner);
+err_lock:
+	mutex_unlock(&acpi_debugger.lock);
+	return ret;
+}
+
+int acpi_debugger_notify_command_complete(void)
+{
+	int ret;
+	int (*func)(void);
+	struct module *owner;
+
+	if (!acpi_debugger_initialized)
+		return -ENODEV;
+	mutex_lock(&acpi_debugger.lock);
+	if (!acpi_debugger.ops) {
+		ret = -ENODEV;
+		goto err_lock;
+	}
+	if (!try_module_get(acpi_debugger.owner)) {
+		ret = -ENODEV;
+		goto err_lock;
+	}
+	func = acpi_debugger.ops->notify_command_complete;
+	owner = acpi_debugger.owner;
+	mutex_unlock(&acpi_debugger.lock);
+
+	ret = func();
+
+	mutex_lock(&acpi_debugger.lock);
+	module_put(owner);
+err_lock:
+	mutex_unlock(&acpi_debugger.lock);
+	return ret;
+}
+
+int __init acpi_debugger_init(void)
+{
+	mutex_init(&acpi_debugger.lock);
+	acpi_debugger_initialized = true;
+	return 0;
+}
+#endif
+
 /*******************************************************************************
  *
  * FUNCTION:    acpi_os_execute
@@ -1127,6 +1323,15 @@ acpi_status acpi_os_execute(acpi_execute_type type,
 			  "Scheduling function [%p(%p)] for deferred execution.\n",
 			  function, context));
 
+	if (type == OSL_DEBUGGER_MAIN_THREAD) {
+		ret = acpi_debugger_create_thread(function, context);
+		if (ret) {
+			pr_err("Call to kthread_create() failed.\n");
+			status = AE_ERROR;
+		}
+		goto out_thread;
+	}
+
 	/*
 	 * Allocate/initialize DPC structure.  Note that this memory will be
 	 * freed by the callee.  The kernel handles the work_struct list  in a
@@ -1151,11 +1356,17 @@ acpi_status acpi_os_execute(acpi_execute_type type,
 	if (type == OSL_NOTIFY_HANDLER) {
 		queue = kacpi_notify_wq;
 		INIT_WORK(&dpc->work, acpi_os_execute_deferred);
-	} else {
+	} else if (type == OSL_GPE_HANDLER) {
 		queue = kacpid_wq;
 		INIT_WORK(&dpc->work, acpi_os_execute_deferred);
+	} else {
+		pr_err("Unsupported os_execute type %d.\n", type);
+		status = AE_ERROR;
 	}
 
+	if (ACPI_FAILURE(status))
+		goto err_workqueue;
+
 	/*
 	 * On some machines, a software-initiated SMI causes corruption unless
 	 * the SMI runs on CPU 0.  An SMI can be initiated by any AML, but
@@ -1164,13 +1375,15 @@ acpi_status acpi_os_execute(acpi_execute_type type,
 	 * queueing on CPU 0.
 	 */
 	ret = queue_work_on(0, queue, &dpc->work);
-
 	if (!ret) {
 		printk(KERN_ERR PREFIX
 			  "Call to queue_work() failed.\n");
 		status = AE_ERROR;
-		kfree(dpc);
 	}
+err_workqueue:
+	if (ACPI_FAILURE(status))
+		kfree(dpc);
+out_thread:
 	return status;
 }
 EXPORT_SYMBOL(acpi_os_execute);
@@ -1358,10 +1571,39 @@ acpi_status acpi_os_get_line(char *buffer, u32 buffer_length, u32 *bytes_read)
 		chars = strlen(buffer) - 1;
 		buffer[chars] = '\0';
 	}
+#else
+	int ret;
+
+	ret = acpi_debugger_read_cmd(buffer, buffer_length);
+	if (ret < 0)
+		return AE_ERROR;
+	if (bytes_read)
+		*bytes_read = ret;
 #endif
 
 	return AE_OK;
 }
+EXPORT_SYMBOL(acpi_os_get_line);
+
+acpi_status acpi_os_wait_command_ready(void)
+{
+	int ret;
+
+	ret = acpi_debugger_wait_command_ready();
+	if (ret < 0)
+		return AE_ERROR;
+	return AE_OK;
+}
+
+acpi_status acpi_os_notify_command_complete(void)
+{
+	int ret;
+
+	ret = acpi_debugger_notify_command_complete();
+	if (ret < 0)
+		return AE_ERROR;
+	return AE_OK;
+}
 
 acpi_status acpi_os_signal(u32 function, void *info)
 {

include/acpi/acpiosxf.h

@@ -349,12 +349,28 @@ void acpi_os_redirect_output(void *destination);
 #endif
 
 /*
- * Debug input
+ * Debug IO
  */
 #ifndef ACPI_USE_ALTERNATE_PROTOTYPE_acpi_os_get_line
 acpi_status acpi_os_get_line(char *buffer, u32 buffer_length, u32 *bytes_read);
 #endif
 
+#ifndef ACPI_USE_ALTERNATE_PROTOTYPE_acpi_os_initialize_command_signals
+acpi_status acpi_os_initialize_command_signals(void);
+#endif
+
+#ifndef ACPI_USE_ALTERNATE_PROTOTYPE_acpi_os_terminate_command_signals
+void acpi_os_terminate_command_signals(void);
+#endif
+
+#ifndef ACPI_USE_ALTERNATE_PROTOTYPE_acpi_os_wait_command_ready
+acpi_status acpi_os_wait_command_ready(void);
+#endif
+
+#ifndef ACPI_USE_ALTERNATE_PROTOTYPE_acpi_os_notify_command_complete
+acpi_status acpi_os_notify_command_complete(void);
+#endif
+
 /*
  * Obtain ACPI table(s)
  */

include/acpi/acpixf.h

@@ -263,6 +263,15 @@ ACPI_INIT_GLOBAL(u32, acpi_gbl_trace_dbg_layer, ACPI_TRACE_LAYER_DEFAULT);
 ACPI_INIT_GLOBAL(u32, acpi_dbg_level, ACPI_DEBUG_DEFAULT);
 ACPI_INIT_GLOBAL(u32, acpi_dbg_layer, 0);
 
+/*
+ * Debugger command handshake globals. Host OSes need to access these
+ * variables to implement their own command handshake mechanism.
+ */
+#ifdef ACPI_DEBUGGER
+ACPI_INIT_GLOBAL(u8, acpi_gbl_method_executing, FALSE);
+ACPI_GLOBAL(char, acpi_gbl_db_line_buf[ACPI_DB_LINE_BUFFER_SIZE]);
+#endif
+
 /*
  * Other miscellaneous globals
  */
@@ -366,6 +375,29 @@ ACPI_GLOBAL(u8, acpi_gbl_system_awake_and_running);
 
 #endif				/* ACPI_APPLICATION */
 
+/*
+ * Debugger prototypes
+ *
+ * All interfaces used by debugger will be configured
+ * out of the ACPICA build unless the ACPI_DEBUGGER
+ * flag is defined.
+ */
+#ifdef ACPI_DEBUGGER
+#define ACPI_DBR_DEPENDENT_RETURN_OK(prototype) \
+	ACPI_EXTERNAL_RETURN_OK(prototype)
+
+#define ACPI_DBR_DEPENDENT_RETURN_VOID(prototype) \
+	ACPI_EXTERNAL_RETURN_VOID(prototype)
+
+#else
+#define ACPI_DBR_DEPENDENT_RETURN_OK(prototype) \
+	static ACPI_INLINE prototype {return(AE_OK);}
+
+#define ACPI_DBR_DEPENDENT_RETURN_VOID(prototype) \
+	static ACPI_INLINE prototype {return;}
+
+#endif				/* ACPI_DEBUGGER */
+
 /*****************************************************************************
  *
  * ACPICA public interface prototypes
@@ -929,6 +961,8 @@ ACPI_EXTERNAL_RETURN_STATUS(acpi_status
 					       void **data,
 					       void (*callback)(void *)))
 
+void acpi_run_debugger(char *batch_buffer);
+
 void acpi_set_debugger_thread_id(acpi_thread_id thread_id);
 
 #endif				/* __ACXFACE_H__ */

include/acpi/platform/aclinux.h

@@ -150,6 +150,8 @@
  */
 #define ACPI_USE_ALTERNATE_PROTOTYPE_acpi_os_readable
 #define ACPI_USE_ALTERNATE_PROTOTYPE_acpi_os_writable
+#define ACPI_USE_ALTERNATE_PROTOTYPE_acpi_os_initialize_command_signals
+#define ACPI_USE_ALTERNATE_PROTOTYPE_acpi_os_terminate_command_signals
 
 /*
  * OSL interfaces used by utilities

include/acpi/platform/aclinuxex.h

@@ -129,6 +129,15 @@ static inline u8 acpi_os_readable(void *pointer, acpi_size length)
 	return TRUE;
 }
 
+static inline acpi_status acpi_os_initialize_command_signals(void)
+{
+	return AE_OK;
+}
+
+static inline void acpi_os_terminate_command_signals(void)
+{
+}
+
 /*
  * OSL interfaces added by Linux
  */

include/linux/acpi.h

@@ -37,6 +37,8 @@
 #include <linux/list.h>
 #include <linux/mod_devicetable.h>
 #include <linux/dynamic_debug.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
 
 #include <acpi/acpi_bus.h>
 #include <acpi/acpi_drivers.h>
@@ -119,6 +121,75 @@ typedef int (*acpi_tbl_table_handler)(struct acpi_table_header *table);
 typedef int (*acpi_tbl_entry_handler)(struct acpi_subtable_header *header,
 				      const unsigned long end);
 
+/* Debugger support */
+
+struct acpi_debugger_ops {
+	int (*create_thread)(acpi_osd_exec_callback function, void *context);
+	ssize_t (*write_log)(const char *msg);
+	ssize_t (*read_cmd)(char *buffer, size_t length);
+	int (*wait_command_ready)(bool single_step, char *buffer, size_t length);
+	int (*notify_command_complete)(void);
+};
+
+struct acpi_debugger {
+	const struct acpi_debugger_ops *ops;
+	struct module *owner;
+	struct mutex lock;
+};
+
+#ifdef CONFIG_ACPI_DEBUGGER
+int __init acpi_debugger_init(void);
+int acpi_register_debugger(struct module *owner,
+			   const struct acpi_debugger_ops *ops);
+void acpi_unregister_debugger(const struct acpi_debugger_ops *ops);
+int acpi_debugger_create_thread(acpi_osd_exec_callback function, void *context);
+ssize_t acpi_debugger_write_log(const char *msg);
+ssize_t acpi_debugger_read_cmd(char *buffer, size_t buffer_length);
+int acpi_debugger_wait_command_ready(void);
+int acpi_debugger_notify_command_complete(void);
+#else
+static inline int acpi_debugger_init(void)
+{
+	return -ENODEV;
+}
+
+static inline int acpi_register_debugger(struct module *owner,
+					 const struct acpi_debugger_ops *ops)
+{
+	return -ENODEV;
+}
+
+static inline void acpi_unregister_debugger(const struct acpi_debugger_ops *ops)
+{
+}
+
+static inline int acpi_debugger_create_thread(acpi_osd_exec_callback function,
+					      void *context)
+{
+	return -ENODEV;
+}
+
+static inline int acpi_debugger_write_log(const char *msg)
+{
+	return -ENODEV;
+}
+
+static inline int acpi_debugger_read_cmd(char *buffer, u32 buffer_length)
+{
+	return -ENODEV;
+}
+
+static inline int acpi_debugger_wait_command_ready(void)
+{
+	return -ENODEV;
+}
+
+static inline int acpi_debugger_notify_command_complete(void)
+{
+	return -ENODEV;
+}
+#endif
+
 #ifdef CONFIG_ACPI_INITRD_TABLE_OVERRIDE
 void acpi_initrd_override(void *data, size_t size);
 #else

tools/power/acpi/Makefile

@@ -10,18 +10,18 @@
 
 include ../../scripts/Makefile.include
 
-all: acpidump ec
-clean: acpidump_clean ec_clean
-install: acpidump_install ec_install
-uninstall: acpidump_uninstall ec_uninstall
+all: acpidbg acpidump ec
+clean: acpidbg_clean acpidump_clean ec_clean
+install: acpidbg_install acpidump_install ec_install
+uninstall: acpidbg_uninstall acpidump_uninstall ec_uninstall
 
-acpidump ec: FORCE
+acpidbg acpidump ec: FORCE
 	$(call descend,tools/$@,all)
-acpidump_clean ec_clean:
+acpidbg_clean acpidump_clean ec_clean:
 	$(call descend,tools/$(@:_clean=),clean)
-acpidump_install ec_install:
+acpidbg_install acpidump_install ec_install:
 	$(call descend,tools/$(@:_install=),install)
-acpidump_uninstall ec_uninstall:
+acpidbg_uninstall acpidump_uninstall ec_uninstall:
 	$(call descend,tools/$(@:_uninstall=),uninstall)
 
 .PHONY: FORCE

tools/power/acpi/tools/acpidbg/Makefile

+# tools/power/acpi/tools/acpidbg/Makefile - ACPI tool Makefile
+#
+# Copyright (c) 2015, Intel Corporation
+#   Author: Lv Zheng <lv.zheng@intel.com>
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License
+# as published by the Free Software Foundation; version 2
+# of the License.
+
+include ../../Makefile.config
+
+TOOL = acpidbg
+vpath %.c \
+	../../../../../drivers/acpi/acpica\
+	../../common\
+	../../os_specific/service_layers\
+	.
+CFLAGS += -DACPI_APPLICATION -DACPI_SINGLE_THREAD -DACPI_DEBUGGER\
+	-I.\
+	-I../../../../../drivers/acpi/acpica\
+	-I../../../../../include
+LDFLAGS += -lpthread
+TOOL_OBJS = \
+	acpidbg.o
+
+include ../../Makefile.rules