JP2020003983A - Control systems and electronic device - Google Patents

Abstract

To provide a control system and an electronic device capable of flexibly changing information.SOLUTION: A control system includes: determination means 30 for determining whether or not to virtualize information recorded in first recording means 13 on the basis of write information written in the first recording means for recording information in a non-rewritable manner or information set for itself; and second virtualization means 31 for virtualizing the information recorded in the first recording means, if the virtualization is determined, so as to cause the information rewritable second recording means to read information in response to a request to read information recorded in the first recording means.SELECTED DRAWING: Figure 5

Description

  The present invention relates to a system for controlling reading of information and an electronic device.

  2. Description of the Related Art Some electronic devices are equipped with an electronic fuse having a characteristic that nonvolatile bit information can be held, and once bit information is changed, it cannot be changed again. Electronic fuses are used to store information that is not required to be overwritten, such as the final configuration information of a device.

  However, there are cases where it is desired to change the stored information, such as when a device is added later as a special order product.

  Therefore, by preparing a virtual electronic fuse and specifying that the value of the virtual electronic fuse be read, the value of the electronic fuse cannot be changed, but the value read by the device can be changed later. Has been proposed (for example, see Patent Document 1).

  However, in the above-described technique, the electronic fuse is read in a plurality of bits, and the number of bits written is even or odd, and the value recorded in the electronic fuse is replaced. There is. In addition, since the value of the electronic fuse is specified to be read, the reading destination must be changed. In this case, there is a problem that information cannot be flexibly changed.

  The present invention has been made in view of the above, and an object of the present invention is to provide a system and an electronic device that allow information to be flexibly changed.

In order to solve the above-described problems, in one embodiment of the present invention, a system for controlling reading of information,
A determination unit that determines whether to virtualize the information recorded in the first recording unit based on the write information written in the first recording unit that records the information in a non-rewritable manner or based on information set therein; When,
If it is determined by the determining means that the virtualization is performed, the first recording is performed such that the information is read from the second rewritable recording means in response to a request to read the information recorded in the first recording means. Virtualization means for virtualizing information recorded in the means.

  According to the present invention, information can be flexibly changed.

FIG. 2 illustrates an example of a hardware configuration of an electronic device. FIG. 4 is a diagram illustrating memory access at the time of reading information. FIG. 4 is a diagram illustrating an example of an electronic fuse mounted on an electronic device. FIG. 4 is a sequence diagram showing a flow of control using an electronic fuse. FIG. 2 is a block diagram illustrating a configuration example of a control system. FIG. 4 is a diagram for explaining memory access at the time of reading information when virtualization is performed. FIG. 4 is a sequence diagram showing a first example of information reading control executed by the control system. FIG. 4 is a sequence diagram showing a second example of information reading control executed by the control system.

  FIG. 1 is a diagram illustrating an example of a hardware configuration of an electronic device. The electronic device includes a CPU 10, a memory 11 such as a DRAM, a nonvolatile storage device 12 such as an HDD, and an electronic fuse 13. The CPU 10 is configured to include an operation unit for performing an operation and a register 14 used by the operation unit for performing the operation. The nonvolatile storage device 12 stores software such as an OS and various applications, various data, and the like.

  The electronic fuse 13 has a feature that once written, it cannot be rewritten again (it cannot be rewritten), and stores information that is not overwritten, such as configuration information of an electronic device. Therefore, by storing the information in the electronic fuse 13, it is possible to prevent a malicious act such as rewriting the configuration information of the device and upgrading the device grade.

  Hardware such as the electronic fuse 13 and the register 14 is associated with the memory 11, and the CPU 10 executes processing by accessing the memory 11 and controls the electronic device. This association is called a map. The area of the memory to which the hardware is mapped is managed by the address given to the memory, and the address is referred to when accessing.

  As shown in FIG. 2, the information stored in the electronic fuse 13 is read out to the memory area 15 to which the electronic fuse 13 is mapped, and the information is written to the register 14 to the memory area 16 to which the register 14 is mapped. The read information is read. Therefore, each information can be acquired by referring to the addresses of the memory areas 15 and 16 and accessing the memory areas 15 and 16.

  The electronic device may be any device such as an information processing device or an image forming device as long as the device has the above hardware.For example, a smartphone, a game machine, a digital camera, a video camera, a printer, an MFP (Multi-Function Peripheral), a projector, and the like. Therefore, in addition to the hardware described above, an input device, a display device, a communication device, an image reading device, an imaging device, and the like can be provided according to the device.

  2. Description of the Related Art In digital cameras, printers, and the like, a circuit (ASIC) for implementing a function specialized for a specific application is mounted as an embedded device. The software executed by the embedded circuit is called embedded software, and in the embedded software, a module corresponding to a plurality of devices with the same instruction (binary) exists. In order to support a plurality of devices with the same binary, it is necessary to determine the device on which the binary operates, and select a process according to the device.

  As one of the methods of determining the device, there is a method of reading information stored in the electronic fuse 13. As shown in FIG. 3, the information stored in the electronic fuse 13 includes, for example, information such as "with" a scanner function and "without" a FAX function. Since this is an example, other information may be used.

  By the way, the electronic device is manufactured as the device A, but may be modified later and used for the development of the device B. In such a case, since the information of the device A is already written in the electronic fuse 13, the location to be read is changed by some method, and the process as the device B must be performed unless the information of the device B is read. Can not.

  For example, if the device A does not have a fax function, but the device B is modified and the fax function is added, and if the location to be read is not changed, the information of the device A indicating that there is no fax function written in the electronic fuse 13 is read. Will be. In this case, although the fax function has been added, the fax module for realizing the fax function does not start, so that the fax function cannot be used.

  The processing at this time will be described with reference to FIG. 4 separately for a case where the portion to be read is changed and a case where it is not changed. It is assumed that the electronic device includes each module as software for realizing each function, and includes a module M20 for selecting a module to be activated depending on the presence or absence of the function, a scanner module 21, and a FAX module 22.

  The module M20 reads the presence or absence of the scanner by referring to the information stored in the electronic fuse 13 (S1 in FIG. 4). Here, since the electronic fuse 13 holds the information of “present”, “present” is returned (S2 in FIG. 4). Then, the module M20 activates the scanner module 21 (S3 in FIG. 4).

  Next, the module M20 refers to the information stored in the electronic fuse 13 and reads the presence or absence of a fax (S4 and S7 in FIG. 4). If "Yes" is written in the electronic fuse 13, "Yes" is returned (S5 in FIG. 4). Then, the fax module 22 is started (S6 in FIG. 4).

  On the other hand, if "none" is written in the electronic fuse 13, "none" is returned (S8 in FIG. 4). In this case, the module M20 does not activate the fax module 22. When the FAX function is added by the modification, the module M20 does not activate the FAX module 22. This is because the information read by the module M20 is the information of the electronic fuse 13 and the information “None” is stored in the electronic fuse 13.

  In order to add a function in this way and use the added function, it is necessary to change a portion to be read. Therefore, a control system having a functional configuration shown in FIG. 5 is implemented. The control system includes at least a determination unit 30 and a virtualization unit 31, and can further include an activation unit 32 and a control unit 33.

  The configuration information of the device and the like are written in the electronic fuse 13, but specific bits are not usually written. Therefore, it is possible to specify the specific bit and write a virtualization flag (value) indicating whether or not the information of the electronic fuse 13 is virtualized. The value of the virtualization flag can be, for example, 1 when virtualization is performed, and 0 when virtualization is not performed.

  Here, to virtualize the information of the electronic fuse 13 means that information stored in an electronic fuse (virtual electronic fuse) different from the electronic fuse 13 is referred to as information stored in the electronic fuse 13. Say. The virtualization flag can be written when it is desired to rewrite the information stored in the electronic fuse 13 after manufacturing.

  The determining unit 30 refers to the virtualization flag written in the electronic fuse 13 and determines whether the information of the electronic fuse 13 should be virtualized.

  When determining whether or not to perform virtualization, the determination unit 30 can refer to its own version information as information set for itself, in addition to the virtualization flag. Since the version information is changed every time a modification or the like is performed, if there is no change from the version at the time of manufacture of the electronic device, it is determined that virtualization is not performed, and if there is a change, it is determined that virtualization is performed. it can.

  The virtualization unit 31 virtualizes the information of the electronic fuse 13 when it is determined to be virtualized based on the determination result of the determination unit 30. Specifically, the virtualization unit 31 determines where the information of the virtual electronic fuse developed on the memory 11 is located on the memory 11 and specifies the address. Since the information of the electronic fuse 13 and the information of the virtual electronic fuse are the same configuration information and the like, the location where the same configuration information and the like other than the information of the electronic fuse 13 are present can be confirmed and the address can be specified. . This is merely an example, and the address may be specified by finding the location where the information of the virtual electronic fuse is located by other methods.

  After specifying the address, the virtualization unit 31 sets the address on the memory 11 where the information of the virtual electronic fuse is expanded as the address of the memory to which the electronic fuse 13 is mapped.

  The information of the virtual electronic fuse can be created as needed, such as when a function is added, and can be stored in the nonvolatile storage device 12.

  The activation unit 32 is realized by a boot loader mounted on the electronic device, and activates the control unit 33 when the electronic device is powered on. Before activating the control unit 33, the activation unit 32 inquires of the determination unit 30 whether to virtualize the electronic fuse 13 and acquires the determination result. In addition, when it is determined in the determination result that the virtualization is to be performed before activating the control unit 33, the activation unit 32 determines what value is to be virtualized when the virtualization unit 31 virtualizes the memory. To the virtualization unit 31. Here, the activation unit 32 instructs to virtualize the information of the electronic fuse 13.

  The control unit 33 is realized by a kernel constituting a core part of an OS mounted on the electronic device, and is started by the start unit 32. The control unit 33 requests reading of the information of the electronic fuse 13 with reference to the set address. If the information of the electronic fuse 13 is not virtualized, the control unit 33 reads the information of the electronic fuse 13 and virtualizes the information. If there is, the information of the virtual electronic fuse at the address set by the virtualization unit 31 is read. Then, the control unit 33 executes control according to the device based on the read electronic fuse information or the virtual electronic fuse information.

  The virtual electronic fuse is realized by a non-volatile storage device 12 such as a rewritable HDD, and the information is expanded on the memory 11 and used. Therefore, the virtual electronic fuse can rewrite information any number of times. Further, since information is read from the virtual electronic fuse by writing only once to a specific bit of the electronic fuse, the rewritten information can be read even if the information of the virtual electronic fuse is rewritten.

  With reference to FIG. 6, memory access in the case of virtualization will be described. As described with reference to FIG. 2, the hardware such as the electronic fuse 13 and the register is mapped to the memory 11, and is configured to be controlled by memory access.

  When the control unit 33 refers to the address of the electronic fuse 13 by virtualizing the address of the memory to which the electronic fuse 13 is mapped, the set address is the memory in which the information of the virtual electronic fuse is expanded. , The information of the virtual electronic fuse can be referred to. Therefore, when virtualized, the information on the true electronic fuse 13 is not referred to.

  With reference to FIG. 7, an example in which information of the electronic fuse in which the information of the device A is written is virtualized by the device B obtained by modifying the device A and the process of the device B is performed will be described. The control system includes an activation unit 32 such as a boot loader, a control unit 33 such as a kernel, a determination unit 30, and a virtualization unit 31.

  The control unit 33 can operate in the same binary in both the device A and the device B, and can switch and control the process of the device A and the process of the device B with reference to the information of the electronic fuse. However, when the device A is modified and the device B is being developed, the information written in the electronic fuse is the information of the device A, and the control unit 33 that operates with reference to the information of the electronic fuse is the device B. Process cannot be switched to Therefore, virtualization of the electronic fuse is performed.

  The activation unit 32 first inquires of the determination unit 30 whether virtualization should be performed (S1 in FIG. 7). This inquiry can be sent to the determination unit 30 as a virtualization determination request. Upon receiving the inquiry, the determination unit 30 refers to the information of the electronic fuse, for example, the value of a specific address (specific bit) (S2 in FIG. 7), and determines whether or not to perform virtualization according to the value. I do. In this example, since the value of the specific address has been written, it is determined to be virtualized (S3 in FIG. 7).

  The determining unit 30 may determine whether to virtualize based on version information or the like set in the electronic fuse, not limited to a specific address value of the electronic fuse.

  When the determination result of the virtualization is returned from the determination unit 30 (S4 in FIG. 7), the activation unit 32 instructs the virtualization unit 31 to start virtualization (S5 in FIG. 7). At this time, the activation unit 32 instructs the virtualization unit 31 what value to virtualize. The virtualization unit 31 receives the instruction from the activation unit 32 and virtualizes the information of the electronic fuse (S6 in FIG. 7). The virtualization unit 31 sets the address of the memory in which the information of the virtual electronic fuse 17 is expanded as the address of the memory to which the electronic fuse is mapped.

  After instructing the virtualization unit 31 to virtualize the electronic fuse, the activation unit 32 activates the control unit 33 (S7 in FIG. 7). After activation, the control unit 33 refers to the address of the electronic fuse and reads information of the electronic fuse (S8 in FIG. 7). Since the set electronic fuse address is the address of the memory in which the information of the virtual electronic fuse 17 is expanded, the control unit 33 reads and acquires the information of the virtual electronic fuse 17 (S9 in FIG. 7).

  FIG. 7 shows an example when virtualization is performed, while FIG. 8 shows an example when virtualization is not performed. The control system includes an activation unit 32 such as a boot loader, a control unit 33 such as a kernel, a determination unit 30, and a virtualization unit 31, as in the example illustrated in FIG.

  The activation unit 32 first inquires of the determination unit 30 whether to virtualize (S1 in FIG. 8). Upon receiving the inquiry, the determination unit 30 refers to the information of the electronic fuse, for example, the value of a specific address (specific bit) (S2 in FIG. 8), and determines whether or not to virtualize according to the value. I do. In this example, since the value of the specific address has not been written, it is determined that virtualization is not to be performed (S3 in FIG. 8).

  Also in this case, the determination unit 30 may determine whether or not to perform virtualization based on not only the value of the specific address of the electronic fuse but also version information set for itself.

  When the determination unit 30 returns a determination result indicating that virtualization is not to be performed (S4 in FIG. 8), the activation unit 32 activates the control unit 33 without instructing the virtualization unit 31 (FIG. 8). S5). After activation, the control unit 33 refers to the address of the electronic fuse and reads information of the electronic fuse (S6 in FIG. 8). Since the set electronic fuse address is the address of the memory to which the electronic fuse information is mapped, the control unit 33 reads and acquires the electronic fuse information (S7 in FIG. 8).

  Regardless of whether the virtualization is performed or not, the information of the electronic fuse or the information of the virtual electronic fuse can be read and acquired by the same operation without changing the binary of the kernel.

  In the above example, virtualization of electronic fuse information has been described.However, the virtualization target is not limited to electronic fuse information, and may be, for example, information stored in a non-writable ROM. Good.

  Although the present invention has been described above with reference to the above-described embodiment as a control system and an electronic device, the present invention is not limited to the above-described embodiment. The present invention can be modified within a range that can be conceived by those skilled in the art, such as other embodiments, additions, changes, and deletions. It is within the scope of the invention. Therefore, a control method and the like executed by the control system can be provided.

10 ... CPU
Reference Signs List 11 memory 12 nonvolatile storage device 13 electronic fuse 14 registers 15 and 16 memory area 17 virtual electronic fuse 20 module M
21 scanner module 22 fax module 30 determination unit 31 virtualization unit 32 activation unit 33 control unit

JP 2010-518540 A

Claims (7)

A system for controlling the reading of information,
Judgment for judging whether or not to virtualize the information recorded in the first recording means based on the write information written in the first recording means for recording the information in a non-rewritable manner or the information set therein. Means,
When it is determined by the determination unit that the virtualization is performed, the information is read from a second recording unit capable of rewriting information in response to a request to read information recorded in the first recording unit. A virtualization means for virtualizing information recorded in the first recording means.   2. The control system according to claim 1, wherein the determination unit refers to an address specified by the first recording unit, and determines whether to perform the virtualization using a value of the address as the write information. 3. . The information recorded in the first recording means and the information recorded in the second recording means are read out on a memory,
The virtualization means sets an address on the memory from which the information recorded on the second recording means is read, as an address on the memory from which the information recorded on the first recording means is read. The control system according to claim 1, wherein Control means for controlling the electronic device;
Starting means for starting the control means,
4. The control system according to claim 1, wherein the activation unit requests the determination unit to determine whether to perform the virtualization before activating the control unit. 5. .   The activation means, before activating the control means, receives the determination result of virtualization from the determination means, and virtualizes the information recorded in the first recording means for the virtualization means. The control system according to claim 4, wherein the control system instructs:   The control unit requests the first recording unit to read information, and when the information recorded in the first recording unit is virtualized, the information recorded in the second recording unit 6. The control system according to claim 4, wherein when the information is not virtualized, information recorded in the first recording unit is read, and the electronic device is controlled using the read information. 7.   An electronic device comprising the control system according to claim 1.