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(12) United States Patent (10) Patent No.: US 9.223,730 B2 Lin Et Al

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(12) United States Patent (10) Patent No.: US 9.223,730 B2 Lin Et Al US00922373OB2 (12) United States Patent (10) Patent No.: US 9.223,730 B2 Lin et al. (45) Date of Patent: Dec. 29, 2015 (54) VIRTUAL SYSTEM MANAGEMENT MODE (56) References Cited DEVICE AND CONTROL METHOD THEREOF U.S. PATENT DOCUMENTS 6.799.316 B1* 9/2004 Aguilar et al. .................... T18, 1 (71) Applicant: WISTRON CORP., New Taipei (TW) 2010/0162242 A1* 6, 2010 Grouzdev ...... ... 718.1 2015,0040 130 A1 2/2015 Ali et al. ........................... T18, 1 (72) Inventors: Wen-Tai Lin, New Taipei (TW); Yuan-Chan Lee, New Taipei (TW) OTHER PUBLICATIONS (73) Assignee: Wistron Corp., New Taipei (TW) Taiwan Patent Office, Office Action, Patent Application No. 101109290, Apr. 11, 2014, Taiwan. (*) Notice: Subject to any disclaimer, the term of this All I Know about SCI, http://diablo0709.blogspot.tw/2013/04/aii-i- patent is extended or adjusted under 35 know-about-sci.html, Apr. 10, 2013, 6 pages, Taiwan. U.S.C. 154(b) by 570 days. KBSMI & KBSCI, http://boy-asmc.blogspot.tw/2011/03/eckbSmi. html, Mar. 25, 2011, 3 pages,Taiwan. (21) Appl. No.: 13/685,618 * cited by examiner (22) Filed: Nov. 26, 2012 Primary Examiner — Nimesh G Patel (65) Prior Publication Data (57) ABSTRACT US 2013/0246678A1 Sep. 19, 2013 A virtual system management mode device, for processing a (30) Foreign Application Priority Data system management interrupt signal generated by a special process, includes a transformation unit, a control unit Mar. 19, 2012 (TW) ............................. 10110929OA memory, and a control unit. The transformation unit trans forms the system management interrupt signal into a virtual (51) Int. Cl. system management interrupt signal. The control unit G06F I3/32 (2006.01) memory stores a plurality of system management interrupt (52) U.S. Cl. processes. The control unit executes one of the system man CPC ...................................... G06F 13/32 (2013.01) agement interrupt processes according to the virtual system (58) Field of Classification Search management interrupt signal. CPC ....................................................... GO6F 13/32 See application file for complete search history. 18 Claims, 3 Drawing Sheets Control unit memory 100 Control unit Central processing unit U.S. Patent Dec. 29, 2015 Sheet 1 of 3 US 9.223,730 B2 00|| I"OIH ÁJOUUQUU1?un?OJ??OO U.S. Patent Dec. 29, 2015 Sheet 2 of 3 US 9.223,730 B2 The transformation unit transforms a system management interrupt signal into a virtual S2O2 system management interrupt signal The control unit obtains a corresponding S204 System management interrupt process S206 The control YeS unit determines whether data of the Selected device is accessible The control unit directly The control unit transmits accesses the data of the a request signal to the Selected device transformation unit according to the SMI proceSS The transformation unit transforms the request signal into a CPU request signal, and transmits it to the CPU The CPU obtains the data of the Selected device, and transmits it to the transformation unit The transformation unit transmits the S216-data of the Selected device to the control unit according to the reply signal The control unit executes the system S218 management interrupt process FIG. 2 END U.S. Patent Dec. 29, 2015 Sheet 3 of 3 US 9.223,730 B2 The transformation unit transforms a system management interrupt Signal into a Virtual S302 System management interrupt Signal The control unit obtains a corresponding S304 System management interrupt process The control Yes unit determines whether the selected NO data can be directly transmitted to the selected device The control unit directly The control unit transmits transmits the selected data a request signal to the to the Selected device transformation unit according to the SMI process The transformation unit transforms the request Signal into a CPU request signal, and transmits it to the CPU The CPU sends the selected data to the selected device END FIG. 3 US 9,223,730 B2 1. 2 VIRTUAL SYSTEM MANAGEMENT MODE ated, however, that the embodiments provide many appli DEVICE AND CONTROL METHOD cable inventive concepts that can be embodied in a wide THEREOF variety of specific contexts. The specific embodiments dis cussed are merely illustrative of specific ways to make and CROSS REFERENCE TO RELATED use the invention, and do not limit the scope of the invention. APPLICATIONS FIG. 1 is a schematic diagram illustrating an embodiment of a virtual system management mode device 100 according This application claims priority of Taiwan Patent Applica to the invention for processing a system management inter tion No. 101109290, filed on Mar. 19, 2012, the entirety of which is incorporated by reference herein. rupt signal SMI generated by a special process. The virtual 10 system management mode device 100 includes a control unit BACKGROUND OF THE INVENTION 110, a control unit memory 112, a transformation unit 120, and a central processing unit 130. In some embodiments, the 1. Field of the Invention control unit 110 may be an embedded controller or a micro The disclosure relates generally to a virtual system man processor, and the control unit memory 112 may store system agement mode device, and more particularly relates to a sys 15 management interrupt processes corresponding to the system tem management mode for a computer system. management interrupt signal SMI. Also, due to the system 2. Description of the Related Art management interrupt processes (such as obtaining a system Generally speaking, a conventional central processing unit password, temporary management, or power management) (CPU) executes a system management interrupt operation by being very important parts for the system, the processing System Management Interrupt (SMI), and the central pro priorities thereofare set as the highest. Further, the operation cessing unit executes system management interrupt process. of the system management interrupt processes is inaccessible When the system management interrupt process is com to the operation system executed by the central processing pleted, a return system management command is generated, unit 130. Thus, if the system management interrupt process is Such that the interrupted operating system process may be used improperly, the computer system would be unsafe. In continued. The system management interrupt process 25 order to prevent this situation, the control unit memory 112 is includes lots of functions, and is widely used in computer systems due to the great number of safety features available only accessible via the control unit 110. Namely, the other and high priority for processing. However, those functions units besides the control unit 110 have no authority to access depend on the support of a CPU. Once the CPU has no the the data of the control unit memory 112. system management interrupt mode, it would be more diffi Furthermore, the system management interrupt signal SMI cult to use the application of the related system management 30 may be generated by any unit of the computer system, or be and keep the system management function safe. Therefore, in generated through an application executed by the central pro Such a case, a method to replace a system management inter cessing unit 130. For example, a temporary management application can obtain a temporary of the computer system by rupt mode is needed. generating a system management interrupt signal. However, BRIEF SUMMARY OF THE INVENTION 35 the mechanism of the System Management Mode is designed for a central processing unit. Thus, in order to make the An embodiment of a virtual system management mode control unit 110 execute the system management process device according to the invention, for processing a system correctly, in Some embodiments, the system management management interrupt (SMI) signal generated by a special interrupt signal SMI may be transformed into a virtual system process, is provided. The virtual system management mode 40 management interrupt signal VSMI which can be understood device includes: a transformation unit for transforming the via the control unit 110. Note that although the system man system management interrupt signal into a virtual system agement interrupt signal SMI is generated via the central management interrupt signal; a control unit memory for Stor processing unit 130 in the embodiment of FIG. 1, the present ing a plurality of system management interrupt processes; invention is not limited thereto. Other devices can directly and a control unit for executing one of the system manage 45 transmit the system management interrupt signal SMI to the ment interrupt processes according to the virtual system man transformation unit 120. agement interrupt signal. In an embodiment of the present invention, when the con trol unit 110 receives the virtual system management inter BRIEF DESCRIPTION OF DRAWINGS rupt signal VSMI, the control unit 110 obtains a correspond 50 ing system management interrupt process from the control The invention will become more fully understood by refer unit memory 112 according to the virtual system manage ring to the following detailed description with reference to the ment interrupt signal VSMI, and the control unit 110 executes accompanying drawings, wherein: the corresponding system management interrupt process FIG. 1 is a schematic diagram illustrating an embodiment according to the virtual system management interrupt signal of a virtual system management mode device according to the 55 VSMI. In an embodiment, the control unit 110 can be per invention; formed by any embedded controller or microprocessor which FIG. 2 is a flowchart of an embodiment of a method for the has been included in the computer system. Therefore, when virtual system management mode device shown in FIG. 1 the control unit 110 receives the virtual system management according to the invention; and interrupt signal VSMI, the present operation process is inter FIG. 3 is a flowchart of another embodiment of a method 60 rupt and stored. After the execution of the system manage for the virtual system management mode device shown in ment interrupt processes are finished, the process returns to FIG.
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