阅读说明：本技术 半导体器件 (Semiconductor device with a plurality of transistors ) 是由 中村淳 山本哲弘 寺岛和昭 小池学 于 2021-04-27 设计创作，主要内容包括：本公开涉及一种半导体器件。该半导体器件执行软件锁步。半导体器件包括：第一电路组,包括在第一地址空间中待被操作的第一知识产权(IP)、第一总线和第一存储器；第二电路组,包括在第二地址空间中待被操作的第二IP、第二总线和第二存储器；可连接至第三存储器的第三总线；以及与第一总线至第三总线耦合的传输控制电路。当软件锁步被执行时,第二电路组将访问地址从第二IP转换到第二存储器,使得第二地址空间中被分配给第二存储器的地址与第一地址空间中被分配给第一存储器的地址相同。(The present disclosure relates to a semiconductor device. The semiconductor device performs software lockstep. The semiconductor device includes: a first circuit group including a first Intellectual Property (IP) to be operated in a first address space, a first bus, and a first memory; a second circuit group including a second IP to be operated in a second address space, a second bus, and a second memory; a third bus connectable to a third memory; and a transmission control circuit coupled with the first bus to the third bus. When the software lockstep is executed, the second circuit group converts the access address from the second IP to the second memory such that the address in the second address space assigned to the second memory is the same as the address in the first address space assigned to the first memory.)

1. A semiconductor device that performs software lockstep (SWLS), comprising:

a first circuit group including a first intellectual property IP to be operated in a first address space, a first bus, and a first memory coupled to the first IP via the first bus;

a second circuit group including a second IP to be operated in a second address space, a second bus, and a second memory coupled to the second IP via the second bus;

a third bus connectable to a third memory; and

a transmit control circuit coupled to the first bus to the third bus and including a comparator,

wherein when the SWLS is executed,

the transfer control circuit is configured to transfer a program for the SWLS from the third memory to the first memory and the second memory,

the first IP is configured to execute the program for the SWLS stored in the first memory to store a first execution result in the first memory,

the second IP is configured to execute the program for the SWLS stored in the second memory to store a second execution result in the second memory;

the transfer control circuit is configured to read the first and second execution results from the first and second memories and compare the first and second execution results using the comparator, and

the second circuit group is configured to convert an access address from the second IP to the second memory such that an address assigned to the second memory in the second address space is the same as an address assigned to the first memory in the first address space.

2. The semiconductor device as set forth in claim 1,

wherein the second bus comprises:

address translation circuitry configured to translate the access address from the second IP to the second memory; and

an operation mode setting register configured to set any one of: a first value indicating that the SWLS is to be executed, and a second value indicating that the SWLS is not to be executed,

wherein when the first value is set in the operating mode setting register, the address translation circuitry is configured to translate the access address from the second IP to the second memory such that the address assigned to the second memory in the second address space is the same as the address assigned to the first memory in the first address space.

3. The semiconductor device according to claim 2, wherein when the second value is set in the operation mode setting register, the address conversion circuit is configured not to convert the access address from the second IP to the second memory.

4. The semiconductor device of claim 2, further comprising a Central Processing Unit (CPU) coupled to the second bus, and

wherein the address translation circuit is configured not to translate an access address from the CPU to the second memory regardless of a value set in the operation mode setting register.

5. The semiconductor device of claim 1, wherein when the SWLS is executed, the transfer control circuit is configured to transfer data for the SWLS from the third memory to the first memory and the second memory.

6. The semiconductor device of claim 1, further comprising a Central Processing Unit (CPU) coupled to the transmission control circuit, and

wherein the transmission control circuit is configured to:

storing the first execution result in the third memory; and

and when the first execution result is inconsistent with the second execution result, transmitting an interrupt signal to the CPU, wherein the interrupt signal is used for informing that the first execution result is inconsistent with the second execution result.

7. The semiconductor device of claim 1, further comprising a Central Processing Unit (CPU) coupled with the first IP, the second IP, and the transmission control circuit, and

wherein the CPU is configured to activate the first IP and the second IP to cause the first IP and the second IP to execute the program for the SWLS after the CPU detects that the transmission of the program for the SWLS by the transmission control circuit has been completed.

8. The semiconductor device of claim 1, further comprising a Central Processing Unit (CPU) coupled with the first IP, the second IP, and the transmission control circuit, and

wherein the CPU is configured to activate the transfer control circuitry to cause the transfer control circuitry to compare the first execution result with the second execution result after the CPU detects that execution of the program for the SWLS through the first IP and the second IP has been completed.

9. The semiconductor device as set forth in claim 1,

wherein the transmission control circuit is configured to transmit a first signal to the first IP and the second IP, the first signal indicating that the transmission of the program for the SWLS is completed, and

wherein the first IP and the second IP are configured to execute the procedure for the SWLS after receiving the first signal.

10. The semiconductor device as set forth in claim 1,

wherein each of the first IP and the second IP is configured to transmit a second signal to the transmission control circuit indicating that execution of the program for the SWLS is complete, and

wherein the transmission control circuit is configured to compare the first execution result with the second execution result after receiving the second signal from the first IP and the second signal from the second IP.

11. The semiconductor device according to claim 1, further comprising a protection circuit on a path that couples the first bus and the second bus without passing through the transmission control circuit, and

wherein the protection circuit is configured to:

when the SWLS is executed, the first IP is prohibited from accessing the second memory via the path coupling the first bus and the second bus, and the second IP is prohibited from accessing the first memory via the path coupling the first bus and the second bus, and

when the SWLS is not executed, allowing the first IP to access the second memory via the path coupling the first bus and the second bus, and allowing the second IP to access the first memory via the path coupling the first bus and the second bus.

Technical Field

The present disclosure relates to semiconductor devices.

Background

Semiconductor devices mounted in autonomous vehicles need to be highly reliable. On the other hand, the semiconductor device may perform an unintended operation due to cosmic rays or physical deterioration. This means that a malfunction may occur in the semiconductor device. Since it is impossible to prevent all failures from occurring in the semiconductor device, it is necessary to detect the failures that have occurred.

One technique for detecting a fault occurring in a semiconductor device is a technique called lockstep. In this technique, two circuit blocks that can realize the same function are used, and each circuit block operates at a specific timing. After the processing of the two circuit blocks is completed, the processing results of the two circuit blocks are compared.

The disclosed techniques are listed below.

[ patent document 1] Japanese unexamined patent application publication No. 2020-

Patent document 1 discloses a semiconductor device for performing software lockstep (SWLS). The semiconductor device disclosed in patent document 1 includes a CPU 10, a CPU 20, a CPU 230, and a memory 260. During the SWLS operation, each of the CPU 10 and the CPU 20 reads a program and data stored in the memory for the SWLS. Each of the CPU 10 and the CPU 20 executes a program for SWLS to write an execution result in the memory 260. The CPU 230 reads the execution result of the CPU 10 and the execution result of the CPU 20 from the memory 260 and compares them.

Disclosure of Invention

The semiconductor device for performing SWLS disclosed in patent document 1 may cause the CPU 10 and the CPU 20 to perform different processes, respectively. Therefore, the semiconductor device that performs SWLS has an advantage that hardware resources (CPU 10 and CPU 20) can be effectively utilized when the SWLS operation and the non-SWLS operation are mixed.

However, during the SWLS operation, each of the CPU 10 and the CPU 20 reads the program and data for the SWLS from the memory 260 and writes the execution result in the memory 260. Further, the CPU 230 reads the execution result of the CPU 10 and the execution result of the CPU 20 from the memory 260. That is, during SWLS operation, the following problems exist: the bus bandwidth required to access the memory 260 increases.

Other objects and novel features will be apparent from the description of the specification and the drawings.

A semiconductor device according to one embodiment performs software lockstep (SWLS). The semiconductor device includes: a first circuit group including a first Intellectual Property (IP) to be operated in a first address space, a first bus, and a first memory coupled to the first IP via the first bus; a second circuit group including a second IP to be operated in a second address space, a second bus, and a second memory coupled to the second IP via the second bus; a third bus connectable to a third memory; and a transmission control circuit coupled with the first bus to the third bus, and including a comparator. When the SWLS is executed, the transfer control circuit transfers a program for the SWLS from the third memory to the first memory and the second memory. The first IP executes a program for SWLS stored in a first memory to store a first execution result in the first memory. The second IP executes a program for SWLS stored in the second memory to store a second execution result in the second memory. The transfer control circuit reads the first and second execution results from the first and second memories, and compares the first and second execution results with the comparator. The second circuit group converts the access address from the second IP to the second memory so that the address assigned to the second memory in the second address space is the same as the address assigned to the first memory in the first address space.

According to one embodiment, the bus bandwidth required to access memory during SWLS operations may be reduced.

Drawings

Fig. 1 is a block diagram showing a configuration example of a semiconductor device according to the first embodiment.

Fig. 2 is a flowchart showing an example of a software lockstep (SWLS) operation of the semiconductor device according to the first embodiment.

Fig. 3 is a flowchart showing an example of SWLS operation of the semiconductor device according to the modification of the first embodiment.

Fig. 4 is a block diagram showing a configuration example of a semiconductor device according to the second embodiment.

Fig. 5 is a block diagram showing a configuration example of a semiconductor device according to the third embodiment.

Detailed Description

Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. In the specification and the drawings, the same or corresponding components are denoted by the same reference numerals, and a repetitive description thereof is omitted. In the drawings, the configuration may be omitted or simplified for convenience of description.

First embodiment

Fig. 1 is a block diagram showing a configuration example of a semiconductor device 1 according to the first embodiment. As shown in fig. 1, the semiconductor device 1 includes a Central Processing Unit (CPU)11, a first circuit group 12, a second circuit group 13, a third bus 14, and a transmission control circuit 15. The first circuit group 12 includes a first Intellectual Property (IP)121, a first bus 122, and a first memory 123. The second circuit group 13 includes a second IP131, a second bus 132, and a second memory 133.

In the first embodiment, the first circuit group 12 and the second circuit group 13 perform software lockstep (SWLS). In SWLS, the same procedure for SWLS is performed by the first IP 121 and the second IP131, and the execution result of the first IP 121 and the execution result of the second IP131 are compared. That is, SWLS refers to a process in which a failure occurring in a semiconductor device is detected by executing a program having the same result by a plurality of IPs and confirming that the execution results of the plurality of IPs are the same.

Additionally, in the first embodiment, an operation when the first circuit group 12 and the second circuit group 13 are performing a series of processes related to SWLS is denoted as an SWLS operation. On the other hand, an operation when the first circuit group 12 and the second circuit group 13 do not perform a series of processes related to SWLS is represented as a non-SWLS operation.

The first memory 123 and the second memory 133 are memories such as, for example, Static Random Access Memories (SRAMs). In the first embodiment, the first memory 123 and the second memory 133 are described as configurations provided separately from the first IP 121 and the second IP131, respectively, but the present disclosure is not limited thereto. That is, the first memory 123 and the second memory 133 may be built in the first IP 121 and the second IP131, respectively.

Further, the semiconductor device 1 is connected to a third memory 2. Specifically, the third memory 2 is connected to the third bus 14 in the semiconductor device 1. The third memory 2 is a memory such as, for example, a double data rate synchronous dynamic random access memory (DDR-SDRAM). In the first embodiment, the third memory 2 is described as being external to the semiconductor device 1, but the present disclosure is not limited thereto. That is, the third memory 2 may be inside the semiconductor device 1.

The CPU 11 is connected to the first IP 121, the second IP131, the second bus 132, and the transfer control circuit 15. During the SWLS operation, the CPU 11 controls the operations of the first IP 121, the second IP131, and the transfer control circuit 15.

The CPU 11 executes a setting for causing the transfer control circuit 15 to transfer the program and data for SWLS from the third memory 2 to the first memory 123 and the second memory 133. The setting is performed, for example, by: the address of the third memory 2 is stored in a register for storing a transmission source address in the transmission control circuit 15, and the addresses of the first memory 123 and the second memory 133 are stored in a register for storing a transmission destination address in the transmission control circuit 15. After that, the CPU 11 transmits an activation request for causing the transfer control circuit 15 to start transferring the program and data for SWLS to the transfer control circuit 15.

Further, after the CPU 11 detects that the transfer control circuit 15 has completed the transfer of the program and data for SWLS, the CPU 11 transmits an activation request for causing each of the first IP 121 and the second IP131 to execute the program and data for SWLS to each of the first IP 121 and the second IP 131. The execution result of the program for SWLS executed by the first IP 121 is stored in the first memory 123 as a first execution result. The execution result of the program for SWLS executed by the second IP131 is stored in the second memory 133 as a second execution result.

Further, after the CPU 11 detects that the first IP 121 and the second IP131 have completed the execution of the program for SWLS, the CPU 11 transmits an activation signal to the transfer control circuit 15, the activation signal being used to cause the transfer control circuit 15 to read the first execution result stored in the first memory 123 and the second execution result stored in the second memory 133 and compare them.

Additionally, the CPU 11 sets a first value indicating SWLS to be executed or a second value indicating SWLS to be not executed in the operation mode setting register 134 included in the second bus 132. Details of the operation mode setting register 134 will be described later.

The first IP 121 is connected to the CPU 11 and the first bus 122. The first bus 122 is connected to a first memory 123. The first IP 121 operates in a first address space. In the first address space, predetermined addresses are assigned to the first memory 123. The first IP 121 accesses the first memory 123 using an address allocated to the first memory 123 in the first address space.

Further, the first IP 121 reads and executes the program for SWLS stored in the first memory 123 based on the control of the CPU 11. At this time, the first IP 121 reads the data for SWLS stored in the first memory 123 and writes the data generated by executing the program for SWLS in the first memory 123 according to the address written in the program for SWLS. The data generated by executing the program for SWLS includes an execution result of the program for SWLS by the first IP 121, that is, a first execution result.

The second IP131 is connected to the CPU 11 and the second bus 132. Further, the second bus 132 is connected to a second memory 133. The second IP131 operates in a second address space. In the second address space, a predetermined address is assigned to the second memory 133. Second IP131 accesses second memory 133 using an address assigned to second memory 133 in the second address space.

Further, the second IP131 reads and executes the program for SWLS stored in the second memory 133 based on the control of the CPU 11. At this time, the second IP131 reads the data for SWLS stored in the second memory 133, and writes the data generated by executing the program for SWLS in the second memory 123 according to the address written in the program for SWLS. The data generated by executing the program for SWLS includes an execution result of the program for SWLS by the second IP131, that is, a second execution result.

The second bus 132 also includes an operation mode setting register 134 and an address conversion circuit 135. A first value indicating that SWLS is to be performed or a second value indicating that SWLS is not to be performed is set in the operation mode setting register 134. As described above, the first value and the second value are set by the CPU 11.

The address conversion circuit 135 determines whether to convert the access address from the second IP131 to the second memory 133 based on the value set in the operation mode setting register 134. More specifically, when the first value is set in the operation mode setting register 134, the address conversion circuit 135 converts the access address from the second IP131 to the second memory 133 so that the address assigned to the second memory 133 in the second address space is the same as the address assigned to the first memory 123 in the first address space. On the other hand, when the second value is set in the operation mode setting register 134, the address conversion circuit 135 does not convert the access address from the second IP131 to the second memory 133.

The program for SWLS is written to be executed by the first IP 121. That is, the address for data access written in the program for SWLS corresponds to the address allocated to the first memory 123 in the first address space. During the SWLS operation, the first IP 121 needs to access the first memory 123 and the second IP131 needs to access the second memory 133 according to the address written in the program for the SWLS. However, in the SWLS operation, since the first IP 121 and the second IP131 execute the same program written for the first IP 121 for SWLS, the second IP131 cannot access the second memory 133 according to an address written in the program for SWLS.

In the first embodiment, when the first circuit group 12 and the second circuit group 13 execute SWLS, the CPU 11 sets a first value indicating that SWLS is to be executed in the operation mode setting register 134. When the first value is set in the operation mode setting register 134, the address conversion circuit 135 converts the access address from the second IP131 to the second memory 133 so that the address assigned to the second memory 133 in the second address space is the same as the address assigned to the first memory 123 in the first address space. As a result, even if the second IP131 executes a program for SWLS written for the first IP 121, the second IP131 can appropriately access the second memory 133.

As described above, in the SWLS operation, the second circuit group 13 converts the access address from the second IP131 to the second memory 133 so that the address assigned to the second memory 133 in the second address space is the same as the address assigned to the first memory 123 in the first address space. Therefore, even if the same program for SWLS is executed, the first circuit group 12 and the second circuit group 13 can appropriately execute SWLS.

On the other hand, in the non-SWLS operation, the second circuit group 13 does not switch the access address from the second IP131 to the second memory 133. Therefore, the second IP131 in the non-SWLS operation can appropriately access the second memory 133. That is, even when the SWLS operation and the non-SWLS operation are mixed, the semiconductor device 1 operates appropriately.

As shown in fig. 1, the semiconductor device 1 includes a path connecting the first bus line 122 and the second bus line 132 without passing through the transmission control circuit 15. Thus, in non-SWLS operation, using this path, first IP 121 may access second memory 133 in addition to first memory 123, and second IP131 may access first memory 123 in addition to second memory 133. Additionally, the semiconductor device 1 includes a path connecting the first bus 122 and the third bus 14 without passing through the transmission control circuit 15, and a path connecting the second bus 132 and the third bus 14 without passing through the transmission control circuit 15. Therefore, in the non-SWLS operation, each of the first IP 121 and the second IP131 can access the third memory 2 using these paths.

The transfer control circuit 15 is connected to the CPU 11, the first bus 122, the second bus 132, and the third bus 14. In the SWLS operation, the transfer control circuit 15 transfers a program and data for the SWLS, reads the first execution result and the second execution result, and compares them.

The transfer control circuit 15 transfers the program and data for SWLS based on the control of the CPU 11. The transfer control circuit 15 reads the program and data for SWLS stored in the third memory 2 via the third bus 14. The transfer control circuit 15 transfers the read program and data for SWLS to the first memory 123 and the second memory 133 via the first bus 122 and the second bus 132. In this case, considering that the access address is switched from the second IP131 to the second memory 123 during the SWLS operation, the transfer control circuit 15 transfers the program and data for the SWLS so that the arrangement to the first memory 123 and the arrangement to the second memory are the same.

Further, the transfer control circuit 15 reads the first execution result stored in the first memory 123 and the second execution result stored in the second memory 133 based on the control of the CPU 11. At this time, the first and second execution results are read via the first and second buses 122 and 132. The transfer control circuit 15 includes a comparator 151, and compares the first execution result and the second execution result using the comparator 151.

Thereafter, the transfer control circuit 15 stores the first execution result in the third memory 2 via the third bus 14. Further, when the first execution result and the second execution result do not coincide with each other, the transmission control circuit 15 transmits an interrupt signal for notifying the CPU 11 that the first execution result and the second execution result do not coincide with each other.

Next, the SWLS operation of the semiconductor device 1 according to the first embodiment will be described. Fig. 2 is a flowchart showing an example of SWLS operation of the semiconductor device 1 according to the first embodiment. The flowchart of fig. 2 includes four processing steps S201-S204. First, in step S201, a process of setting an address for the SWLS operation is performed. In the process of setting the address, the CPU 11 sets a first value indicating that SWLS is to be executed in the operation mode setting register 134. By setting the first value, the conversion of the access address from the second IP131 to the second memory 133 is performed.

Next, in step S202, a process of transferring a program and data for SWLS is performed. In the process of transferring the program and data for SWLS, the CPU 11 executes a setting that causes the transfer control circuit 15 to transfer the program and data for SWLS from the third memory 2 to the first memory 123 and the second memory 133, and then activates the transfer control circuit 15 to cause the transfer control circuit 15 to start transfer. The activated transfer control circuit 15 reads the program and data for SWLS stored in the third memory 2 via the third bus 14. The transfer control circuit 15 transfers the read program and data for SWLS to the first memory 123 and the second memory 133 via the first bus 122 and the second bus 132.

At this time, the transfer control circuit 15 transfers the program and data for SWLS to the first memory 123 and the second memory 133 in one reading process. That is, the bus bandwidth required to access the third memory 3 can be reduced as compared with the following case: a case where the transfer from the third memory 2 to the first memory 123 and the transfer from the third memory 2 to the second memory 133 are separately performed. Additionally, in the first embodiment, since the address conversion circuit 135 performs the conversion of the access address, the first IP 121 and the second IP131 can perform the same procedure for SWLS. As a result, the transfer of the program for SWLS can be performed in one transfer process.

Next, in step S203, the following processing is executed: the program for SWLS is executed. In the process of executing the program for SWLS, the CPU 11 detects that the transfer of the program and data for SWLS has been completed by the transfer control circuit 15. For example, the transmission control circuit 15 transmits a signal for notifying the completion of transmission to the CPU 11, and the CPU 11 receives the signal, whereby the CPU 11 can detect that the transmission processing by the transmission control circuit 15 has been completed. After the CPU 11 detects that the transfer control circuit 15 has completed the transfer of the program and data for SWLS, the CPU 11 activates the first IP 121 and the second IP131 to cause the first IP 121 and the second IP131 to execute the program for SWLS.

The activated first IP 121 reads and executes the program for SWLS stored in the first memory 123. At this time, the first IP 121 accesses the first memory 123 using the address allocated to the first memory 123 in the first address space. The first IP 121 stores the execution result of the program for SWLS as a first execution result in the first memory 123.

Further, the activated second IP131 reads and executes the program for SWLS stored in the second memory 133. At this time, the second IP131 accesses the second memory 133 using the address assigned to the second memory 133 in the second address space. The second IP131 stores the execution result of the program for SWLS as a second execution result in the second memory 133.

A first address space in which the first IP 121 operates is different from a second address space in which the second IP131 operates. That is, the addresses in the first address space assigned to the first memory 123 are different from the addresses in the second address space assigned to the second memory 133. In the SWLS operation, the first IP 121 and the second IP131 perform the same procedure for the SWLS. Thus, in the SWLS operation, second circuit group 13 converts the access address from second IP131 to second memory 133 so that the address in the second address space assigned to second memory 133 is the same as the address in the first address space assigned to first memory 123.

Specifically, the address conversion circuit 135 confirms the value set in the operation mode setting register 134. In the SWLS operation, since the first value indicating that SWLS is to be performed is set in step S201, the address conversion circuit 135 converts the access address from the second IP131 to the second memory 133 so that the address in the second address space assigned to the second memory 133 is the same as the address in the first address space assigned to the first memory 123. As a result, even if the second IP131 executes a program for SWLS written for the first IP 121, the second IP131 can appropriately implement the operation of SWLS.

Finally, in step S204, a process of comparing the execution results is performed. In the process of comparing the execution results, the CPU 11 detects that the first IP 121 and the second IP131 have completed execution of the program for SWLS. For example, each of the first IP 121 and the second IP131 transmits a signal for notifying completion of the execution processing of the program for SWLS to the CPU 11, and the CPU 11 receives the signal from the first IP 121 and the signal from the second IP131, whereby the CPU 11 can detect that the first IP 121 and the second IP131 have completed the execution processing of the program for SWLS. After the CPU 11 detects that the first IP 121 and the second IP131 have completed the execution of the program for SWLS, the CPU 11 activates the transfer control circuit 15 to cause the transfer control circuit 15 to read the first execution result stored in the first memory 123 and the second execution result stored in the second memory 133 and compare them.

The activated transfer control circuit 15 reads the first execution result from the first memory 123 via the first bus 122. Further, the transfer control circuit 15 reads the second execution result from the second memory 133 via the second bus 132. The transfer control circuit 15 compares the first execution result with the second execution result using the comparator 151. The transfer control circuit 15 stores the first execution result in the third memory 2 via the third bus 14. The transfer control circuit 15 stores only one execution result in the third memory when comparing the two execution results, and thus does not increase the bus bandwidth required to access the third memory 2. Additionally, when the first execution result and the second execution result do not coincide with each other, the transmission control circuit 15 transmits an interrupt signal for notifying that the first execution result and the second execution result do not coincide with each other to the CPU 11.

When the processing of step S204 is completed, a series of operations of SWLS is completed. Thereafter, when the semiconductor device 1 shifts from the SWLS operation to the non-SWLS operation, the CPU 11 sets a second value indicating that SWLS is not executed in the operation mode setting register 134.

As described above, according to the first embodiment, since the transfer control circuit 15 can transfer the program and data for SWLS by performing the read processing once from the third memory 2, in other words, the transfer processing once from the third memory 2 to the first memory 123 and the second memory 133, the bus bandwidth required to access the third memory 2 can be reduced.

Further, in the first embodiment, when SWLS is executed, the second circuit group 13 switches the access address from the second IP131 to the second memory 133 so that the address in the second address space assigned to the second memory 133 is the same as the address in the first address space assigned to the first memory 123. As a result, even if the second IP131 executes a program for SWLS written for the first IP 121, the second IP131 can appropriately access the second memory 133.

In fig. 1, the first circuit group 12 and the second circuit group 13 are shown to have the same configuration provided with an IP, a bus, and a memory, but the first circuit group 12 and the second circuit group 13 do not necessarily have to have the same configuration. That is, as long as the first circuit group 12 and the second circuit group 13 can perform SWLS, they may have an asymmetric configuration.

In fig. 1, each of the first circuit group 12 and the second circuit group 13 is shown to have a configuration provided with one IP, but each of the first circuit group 12 and the second circuit group 13 may be provided with a plurality of IPs. In this case, since the SWLS operation and the non-SWLS operation can be mixed for each IP, the address conversion circuit 135 can convert the access address for each IP.

In fig. 1, the operation mode setting register 134 and the address conversion circuit 135 are illustrated as configurations included in the second bus 132, but the present disclosure is not limited thereto. That is, the operation mode setting register 134 and the address conversion circuit 135 need only be included in the second circuit group 13, and need not be included in the second bus 132. For example, the second IP131 may include an operation mode setting register 134 and an address conversion circuit 135.

In fig. 1, the operation mode setting register 134 and the address conversion circuit 135 are shown as configurations included in the second bus 132 on the second circuit group 13 side, but they may be included in the first bus 122 on the first circuit group 12 side. In this case, a program for SWLS may be written to correspond to an address in the second address space that is assigned to second memory 133.

In fig. 2, although the process of setting an address for the SWLS operation is described as being performed before the process of transferring the program and data for the SWLS, the order of the process of setting an address for the SWLS operation and the process of transferring the program and data for the SWLS may be switched.

The CPU 11 may be configured to be accessible by the second memory 133 during SWLS operation and non-SWLS operation. In this case, the address conversion circuit 135 does not convert the access address from the CPU 11 to the second memory 133 regardless of the value set in the operation mode setting register 134.

Modification of the first embodiment

Next, a modification of the first embodiment will be described. In the first embodiment, although the first IP 121 and the second IP131 are described as performing the same procedure for SWLS, the first IP 121 and the second IP131 may perform different procedures for SWLS. In a modification of the first embodiment, the configuration and operation of the semiconductor device 1 when different programs for SWLS are executed will be described.

The first IP 121 executes a first program for SWLS. A first program for SWLS is written to correspond to an address in the first address space that is allocated to first memory 123. The second IP131 executes the second program for SWLS. A second program for SWLS is written to correspond to an address in a second address space that is assigned to second memory 133. Although the first program for SWLS and the second program for SWLS are different in the description about the following, the execution result of the first program for SWLS and the execution result of the second program for SWLS are the same: an address for accessing the first memory 123 and an address for accessing the second memory 133.

Further, since the second IP131 executes the second program of SWLS to be written by the second IP131, the operation mode setting register 134 and the address conversion circuit 135 are not required. Therefore, the semiconductor device 1 according to the modification of the first embodiment does not include the operation mode setting register 134 and the address conversion circuit 135. That is, in the modification of the first embodiment, the second circuit group 13 does not switch the access address from the second IP131 to the second memory 133 during the SWLS operation.

Fig. 3 is a flowchart showing an example of SWLS operation of the semiconductor device 1 according to the modification of the first embodiment. In the processing of steps S202a and S202b, the flowchart of fig. 3 is different from the flowchart of fig. 2. Additionally, in the flowcharts of fig. 2 to 3, the processing of steps S203 and S204 is the same.

In step S202a of fig. 3, a process of transferring data for SWLS is performed. In the process of transferring data for SWLS, the transfer control circuit 15 reads the data for SWLS stored in the third memory 2 via the third bus 14. The transfer control circuit 15 transfers the read data for SWLS to the first memory 123 and the second memory 133 via the first bus 122 and the second bus 132. The process of step S202 of fig. 3 is different from the process of step S202 of fig. 2 in that only data for SWLS is transferred, and a program for SWLS is not transferred.

In step S202b of fig. 3, a process of transferring a program for SWLS is performed. In the process of transferring the program for SWLS, the transfer control circuit 15 reads the first program for SWLS stored in the third memory 2 via the third bus 14, and transfers the read first program for SWLS to the first memory 123 via the first bus 122. Additionally, the transfer control circuit 15 reads the second program for SWLS stored in the third memory 2 via the third bus 14, and transfers the read second program for SWLS to the second memory 133 via the first bus 132.

According to the modification of the first embodiment, since the transfer control circuit 15 can transfer data for SWLS from the third memory 2 to the first memory 123 and the second memory 133 by one transfer process, the bus bandwidth required to access the third memory 2 can be reduced.

In the above description, the transfer control circuit 15 performs the transfer processing of the first program for SWLS and the second program for SWLS in step S202b, but the first IP 121 and the second IP131 may perform the transfer processing. In this case, after the CPU 11 detects that the transfer control circuit 15 has completed the transfer of the data for SWLS, the CPU 11 activates the first IP 121 to cause the first IP 121 to start transferring the first program for SWLS, and activates the second IP131 to cause the second IP131 to start transferring the second program for SWLS.

The activated first IP 121 transfers the first program for SWLS from the third memory 2 to the first memory 123 via a path connecting the first bus 122 and the third bus 14. Further, the activated second IP131 transfers the second program for SWLS from the third memory 2 to the second memory 133 via a path connecting the second bus 132 and the third bus 14.

Second embodiment

Next, a second embodiment will be described. The semiconductor device according to the second embodiment is different from the semiconductor device according to the first embodiment in that communication can be performed between the first IP and the transmission control circuit and between the second IP and the transmission control circuit. Fig. 4 is a block diagram showing a configuration example of a semiconductor device 1a according to the second embodiment. As shown in fig. 4, the first circuit group 12, the first IP 121, the second circuit group 13, the second IP131, and the transmission control circuit 15 in fig. 1 are changed to a first circuit group 12a, a first IP 121a, a second circuit group 13a, a second IP131 a, and a transmission control circuit 15a, respectively.

The transmission control circuit 15a is connected to the first IP 121a and the second IP131 a. After the transfer control circuit 15a has completed the transfer processing of the program and data for SWLS, the transfer control circuit 15a transmits an activation request for causing the first IP 121a to execute the program for SWLS to the first IP 121a, and transmits an activation request for causing the second IP131 a to execute the program for SWLS to the second IP131 a. These activation requests are performed, for example, by: a signal for notifying that the transfer process has been completed is transmitted from the transfer control circuit 15a to the first IP 121a, and a signal for notifying that the transfer process has been completed is transmitted from the transfer control circuit to the second IP131 a. After receiving the activation request, each of the first IP 121a and the second IP131 a executes a program for SWLS.

After the first IP 121a and the second IP131 a have completed the execution processing of the program for SWLS, each of the first IP 121a and the second IP131 a transmits an activation request for causing the transfer control circuit 15a to read and compare the first execution result stored in the first memory 123 and the second execution result stored in the second memory 133 to the transfer control circuit 15 a. These activation requests are performed, for example, by: a signal for notifying completion of execution processing is transmitted from the first IP 121a to the transmission control circuit 15a, and a signal for notifying completion of execution processing is transmitted from the second IP131 a to the transmission control circuit 15 a. After receiving the activation request from the first IP 121a and the activation from the second IP131 a, the transfer control circuit 15a compares the first execution result with the second execution result.

As described above, according to the second embodiment, the transfer control circuit 15a can transmit an activation request for causing the first IP 121a to execute a program for SWLS to the first IP 121a and transmit an activation request for causing the second IP131 a to execute a program for SWLS to the second IP131 a without using the CPU 11. Further, each of the first IP 121a and the second IP131 a may transmit, to the transmission control circuit 15a, an activation request for causing the transmission control circuit 15a to read the first execution result and the second execution result and compare them, without using the CPU 11. As a result, the semiconductor device 1a according to the second embodiment can significantly reduce the burden of the CPU 11 in performing interrupt processing, as compared with the semiconductor device 1 according to the first embodiment. Specifically, as the number of IPs included in the first circuit group 12a and the second circuit group 13a increases, the effect of reducing the load on the CPU 11 becomes more significant.

The activation request described above may include processing for register setting of the transfer control circuit 15a, the first IP 121a, or the second IP131 a. Additionally, even when the transmission control circuit 15a, the first IP 121a, and the second IP131 a receive activation requests while performing other processes, the activation requests may be queued and the queued activation requests may be processed later.

Third embodiment

Next, a third embodiment will be described. The semiconductor device according to the third embodiment is different from the semiconductor devices according to the first and second embodiments in that the transmission control circuit includes a protection circuit. Fig. 5 is a block diagram showing a configuration example of a semiconductor device 1b according to the third embodiment. As shown in fig. 5, the semiconductor device 1b includes a protection circuit 16 on a path connecting the first bus 122 and the second bus 132.

The first IP 121 accesses the second memory 133 included in the second circuit group 13 via a path connecting the first bus 122 and the second bus 132. Additionally, the second IP131 accesses the first memory 123 included in the first circuit group 12 via a path connecting the first bus 122 and the second bus 132. Accordingly, the first IP 121 and the second IP131 can increase the memory capacity that can be used.

The protection circuit 16 controls the permission or non-permission of the following accesses: access from first IP 121 to second memory 133 and access from second IP131 to first memory 123. Specifically, when SWLS is performed, the protection circuit 16 prohibits the first IP 121 from accessing the second memory 133 via a path connecting the first bus 122 and the second bus 132, and prohibits the second IP131 from accessing the first memory 123 via a path connecting the first bus 122 and the second bus 132. On the other hand, when the SWLS is not executed, the protection circuit 16 allows the first IP 121 to access the second memory 133 via a path connecting the first bus 122 and the second bus 132, and allows the second IP131 to access the first memory via a path connecting the first bus 122 and the second bus 132.

As described above, according to the third embodiment, the protection circuit 16 monitors accesses from one circuit group to another circuit group, such as an access from the first IP 121 to the second memory 133 and an access from the second IP131 to the first memory 123, and prohibits such accesses during the SWLS operation. Thus, for example, the problem that the following failure is not detected can be avoided: during the SWLS operation, the first IP 121 stores the same data in both the first memory 123 and the second memory 133.

The protection circuit 16 may determine whether SWLS is being performed based on the value set in the operation mode setting register 134. The protection circuit 16 may also be configured to directly receive information from the CPU 11 about whether SWLS is being executed.

Further, in the semiconductor device 1b, the first IP 121 can access the second memory 133 and the second IP131 can access the first memory 123 via the third bus 14 without using a path connecting the first bus 122 and the second bus 132. However, an access using the third bus 14 is not preferable because contention for access to the third bus 14 may increase.

Although the invention made by the present inventors has been specifically described based on the embodiments, it goes without saying that the present invention is not limited to the above-described embodiments, and various changes may be made without departing from the scope of the invention.