TW202424763A - Abnormality detection module and method of direct memory access, and electronic system using the same - Google Patents

Abstract

An abnormality detection module of direct memory access (DMA) has one or more abnormality detection devices of the DMA. The abnormality detection device of the DMA is used for detecting whether the DMA device electrically connected to the abnormality detection device of the DMA is abnormal. According to a received a DMA abnormality enable signal and a received burst signal of the DMA device, the abnormality detection device of the DMA generates an upper bound address which the DMA device access a memory. Then, according to the upper bound address and an upper bound address threshold, the abnormality detection device of the DMA then generates a DMA access stop signal to the DMA device and generates an interrupt flag signal.

Description

Direct memory access anomaly detection module, method and electronic system using the same

The present invention relates to a technology for detecting abnormalities of a direct memory access (DMA) device, and in particular to a DMA abnormality detection module, method and electronic system using the same, which can prevent the abnormality of the DMA device from causing system interruption or crash and allow a software program to intervene to handle the abnormal DMA device.

When a DMA device is abnormal, a DMA trap may occur at the least, and a DMA overflow may occur at the most serious, causing the electronic system to crash. The solution of the prior art is to restrict the cache used by the DMA device through software to be configured only at the last page of the static random access memory, and store the cache marked at the last page of the static random access memory.

According to the previous technology, each time the program is interrupted, the electronic system will use the processor's computing power to check whether the mark is erased. After determining that the mark is erased, the electronic system jumps to the direct memory access overflow process. However, the above method cannot prevent multiple direct memory access devices from having direct memory access overflows at the same time, and the above method uses the processor's computing power through software, which may cause the direct memory access device to be judged to be occupied for too long, causing the electronic system to directly jump to the direct memory access device timeout (DMA time out) process.

From the above description, it can be understood that the technical problem to be solved by the present invention is how to solve the technical problem of direct memory access device timeout and direct memory access overflow by monitoring the line of the direct memory access device. Furthermore, the technical solution of the present invention can prevent multiple direct memory access devices from timeout and overflow at the same time.

To solve the above-mentioned known problems, an embodiment of the present invention provides a direct memory access abnormality detection module, which includes one or more direct memory access abnormality detection devices. The direct memory access abnormality detection device is used to detect whether the direct memory access device electrically connected to it is abnormal. The direct memory access abnormality detection device generates an upper bound address of the direct memory access device accessing the memory according to the received direct memory access abnormality detection enable signal and the received burst signal of the direct memory access device, and generates a direct memory access stop signal and an interrupt flag signal to the direct memory access device according to the upper bound address and the received upper bound address threshold.

To solve the above-mentioned known problems, an embodiment of the present invention provides another direct memory access abnormality detection module, which includes one or more direct memory access abnormality detection devices. The direct memory access abnormality detection device is used to detect whether the direct memory access device electrically connected to it is abnormal. The direct memory access abnormality detection device is enabled according to the received direct memory access abnormality detection enable signal. When the direct memory access abnormality detection device is enabled, it counts based on the received clock to generate a count value. If the count value reaches the count value threshold, the direct memory access abnormality detection device will generate a direct memory access stop signal to the direct memory access device and an interrupt flag signal. When the direct memory access abnormality detection device is enabled, if the direct memory access abnormality detection device receives a work completion signal from the direct memory access device, the count value is reset to zero.

To solve the above-mentioned known problems, an embodiment of the present invention further provides an electronic system, which includes the above-mentioned direct memory access abnormality detection module, one or more direct memory access abnormality detection devices, and one or more data processing circuits. The one or more data processing circuits are electrically connected to one or more direct memory access devices and are used to access one or more data in the memory through the one or more direct memory access devices.

To solve the above-mentioned known problems, the embodiment of the present invention further provides a direct memory access abnormality detection method, which is performed by a direct memory access abnormality detection device and includes the following steps: receiving a direct memory access abnormality detection enable signal to enable the direct memory access abnormality detection device, and receiving an upper address threshold value of a direct memory access detection device electrically connected to the direct memory access abnormality detection device. After the direct memory access detection device is triggered to work, the upper limit address of the direct memory access device for accessing the memory is generated according to the direct memory access abnormal detection enable signal and the burst signal of the direct memory access device. According to the upper limit address and the upper limit address threshold value, a direct memory access stop signal is generated to the direct memory access device and an interrupt flag signal.

To solve the above-mentioned known problems, an embodiment of the present invention even provides a direct memory access abnormality detection method, which is performed by a direct memory access abnormality detection device and includes the following steps: receiving a direct memory access abnormality detection enable signal to enable the direct memory access abnormality detection device, and receiving a count value threshold value of a direct memory access detection device electrically connected to the direct memory access abnormality detection device. After the direct memory access test device is triggered to make the direct memory access test device work, counting is performed based on the received clock according to the direct memory access abnormal detection enable signal to generate a count value. A direct memory access stop signal and an interrupt flag signal are generated to the direct memory access device according to the count value and the count value threshold. After the direct memory access test device is triggered to make the direct memory access test device work, the count value is reset to zero according to the direct memory access abnormal detection enable signal and the work completion signal of the direct memory access test device.

As mentioned above, the direct memory access abnormality detection technology provided by the present invention can generate a stop signal to automatically stop the abnormal direct memory access device when an abnormality is detected in the direct memory access device, so as to avoid the technical problem of memory access overflow, so that the memory will not be overwritten and the system will not crash, and the direct memory access device will not be stopped.

In view of the above technical problems to be overcome, the embodiments of the present invention provide a direct memory access abnormality detection module, method and electronic system that can automatically handle the abnormality of the direct memory access device when the electronic system is running. Through the direct memory access abnormality detection module, method and electronic system provided by the present invention, the abnormal direct memory access device can be automatically stopped, and system interruption and system crash can be avoided. Furthermore, the abnormality can be handled through a software program, and the handling includes, for example, resetting the data processing circuit electrically connected to the direct memory access device, resetting the direct memory access device, disabling the direct memory access device or notifying the handling personnel for handling.

Next, please refer to FIG. 1, which is a block diagram of an electronic system using a direct memory access abnormality detection module according to a first embodiment of the present invention. The electronic system 1 includes a direct memory access abnormality detection module 11, one or more direct memory access devices 12, and one or more data processing circuits (not shown in the figure). The direct memory access abnormality detection module 11 includes one or more direct memory access abnormality detection devices 111, and each direct memory access abnormality detection device 111 is electrically connected to a direct memory access device 12 to achieve the purpose of simultaneously detecting whether multiple direct memory access devices 12 are abnormal. Each direct memory access device 12 is electrically connected to a data processing circuit, and the data processing circuit is used to access one or more data in the memory through the electrically connected direct memory access device.

In the embodiment of the present invention, the data processing circuit includes an image data processing circuit, a sensor data processing circuit, an audio data processing circuit, a control data processing circuit, a packet data processing circuit or a peripheral device data processing circuit, and the present invention is not limited by the type of the data processing circuit. The type of the data processing circuit is related to the type of the electronic system 1. For example, if the electronic system 1 is a server, the multiple data processing circuits include an image data processing circuit, an audio data processing circuit and a packet data processing circuit. The memory can be a random access memory, such as a static random access memory, but the present invention is not limited by the type of memory. For example, the memory can also be a flash memory.

Each direct memory access abnormality detection device 111 is used to detect whether the electrically connected direct memory access device 12 is abnormal. The direct memory access abnormality detection device 111 generates an upper limit address DADD for the direct memory access device 12 to access the memory according to the received direct memory access abnormality detection enable signal ENCH and the received burst signal BST of the direct memory access device 12, and generates a direct memory access stop signal STP to the direct memory access device 12 and an interrupt flag signal INTFL according to the upper limit address DADD and the received upper limit address threshold value ADDTH.

Furthermore, the burst signal BST has an upper limit address DADD for the direct memory access device 12 to access the memory, wherein the upper limit address DADD refers to the largest one of multiple addresses of the access data of the direct memory access device 12 to access the data in the memory. For example, if the direct memory access device 12 wants to access the data of the addresses 0x5510, 0x5520, and 0x5530 in the memory continuously, the burst signal BST issued by the direct memory access device 12 will include the upper limit address DADD of 0x5530. If the upper address threshold value ADDTH is 0x5550 and the upper address DADD is 0x5530, the direct memory access abnormality detection device 111 does not generate the direct memory access stop signal STP and the interrupt flag signal INTFL. If the upper address threshold value ADDTH is 0x5550 and the upper address DADD is 0x5560, the direct memory access abnormality detection device 111 generates the direct memory access stop signal STP and the interrupt flag signal INTFL to stop the direct memory access abnormality detection device 111 from working.

Please refer to FIG. 1 and FIG. 2. FIG. 2 is a block diagram of the direct memory access abnormality detection device of the first embodiment of the present invention. The direct memory access abnormality detection device 111 of FIG. 1 can be implemented in the implementation manner of FIG. 2, but the present invention does not limit the direct memory access abnormality detection device 111 to only be implemented in the manner of FIG. 2. The direct memory access abnormality detection device 111 includes a plurality of hardware circuits, and the plurality of hardware circuits include a logic and gate 1111, a comparator 1112, and an interrupt flag generator 1113. The logic and gate 111 is electrically connected to the direct memory access device 12 , the comparator 1112 is electrically connected to the logic and gate 1111 and the direct memory access device 12 , and the interrupt flag generator 1113 is electrically connected to the comparator 1112 .

The logic and gate 1111 is used to receive the burst signal BST and the direct memory access abnormal detection enable signal ENCH, and perform logic and operation on the burst signal BST and the direct memory access abnormal detection enable signal ENCH to generate the upper limit address DADD for the direct memory access device 12 to access the memory. The comparator 1112 is used to receive and compare the upper limit address DADD with the upper limit address threshold value ADDTH, and generate the comparison result as the direct memory access stop signal STP to the direct memory access device 12. The interrupt flag generator 1113 is used to generate the interrupt flag signal INTFL according to the direct memory access stop signal STP.

Furthermore, in addition to including a plurality of hardware circuits, the direct memory access abnormality detection device 111 may also have a processing module implemented by a software program. The processing module may be used to process the stopped direct memory access device 12 according to the interrupt flag signal, wherein the processing includes resetting the data processing circuit electrically connected to the direct memory access device 12, resetting the direct memory access device 12, disabling the direct memory access device 12, or notifying a processing personnel for processing.

Please refer to FIG. 1 to FIG. 3 , FIG. 3 is a flow chart of the direct memory access abnormality detection method of the first embodiment of the present invention. The direct memory access abnormality detection method is executed by the electronic system 1. In step S301, the direct memory access abnormality detection device 111 receives the direct memory access abnormality detection enable signal ENCH to enable the direct memory access abnormality detection device 111. In step S302, the direct memory access abnormality detection device 111 receives the upper limit address threshold value ADDTH of the direct memory access device 12. Next, in step S303, the direct memory access test device 12 of the electronic system 1 is triggered. After the direct memory access test device 12 is triggered, in step S304, the direct memory access test device 12 operates to access data from the memory.

Then, in step S305, the direct memory access abnormality detection device 111 obtains the upper limit address DADD from the received burst signal BST, and determines whether the upper limit address DADD reaches the upper limit address threshold value ADDTH. If the upper limit address DADD does not reach the upper limit address threshold value ADDTH, then continue to execute step S306, otherwise, execute step S307. In step S307, the direct memory access abnormality detection device 111 generates a direct memory access stop signal STP to the direct memory access device 12 and an interrupt flag signal INTFL to stop the direct memory access device 12 and allow the processing module to process the abnormal direct memory access device 12. In step S306, the electronic system 1 determines whether the direct memory access device 12 has finished working. If so, the direct memory access device 12 has finished working. Otherwise, step S304 is executed, that is, the direct memory access device 12 continues to work.

Next, please refer to FIG. 4, which is a block diagram of an electronic system using a direct memory access abnormality detection module according to a second embodiment of the present invention. The electronic system 2 includes a direct memory access abnormality detection module 21, one or more direct memory access devices 22, and one or more data processing circuits (not shown in the figure). The direct memory access abnormality detection module 21 includes one or more direct memory access abnormality detection devices 211, and each direct memory access abnormality detection device 211 is electrically connected to a direct memory access device 22 to achieve the purpose of simultaneously detecting whether multiple direct memory access devices 22 are abnormal. Each direct memory access device 22 is electrically connected to a data processing circuit, and the data processing circuit is used to access one or more data in the memory through the direct memory access device electrically connected to it. As described above, the data processing circuit may include an image data processing circuit, a sensor data processing circuit, an audio data processing circuit, a control data processing circuit, a packet data processing circuit, or a peripheral device data processing circuit, but the present invention is not limited thereto.

Each direct memory access abnormality detection device 211 is used to detect whether the direct memory access device 22 electrically connected thereto is abnormal. The direct memory access abnormality detection device 211 is enabled according to the received direct memory access abnormality detection enable signal ENCH. When the direct memory access abnormality detection device 211 is enabled, it counts based on the received clock CLK to generate a count value CNT. If the count value CNT reaches the count value threshold value CNTTH received by the direct memory access abnormality detection device 211, the direct memory access abnormality detection device 211 will generate a direct memory access stop signal STP to the direct memory access device 22 and an interrupt flag signal INTFL; if the direct memory access abnormality detection device 211 receives a work completion signal CP from the direct memory access device 22 before the count value CNT reaches the count value threshold value CNTTH received by the direct memory access abnormality detection device 211, the direct memory access abnormality detection device 211 will reset the count value CNT to zero. In short, the method of FIG. 1 is to detect the upper limit address of the direct memory access device 12 accessing the memory, and compared with the method of FIG. 1 , the method of FIG. 4 is to detect whether the time occupied by the direct memory access device 22 has exceeded, so as to determine whether the direct memory access device 22 is abnormal.

Next, please refer to Figures 4 and 5. Figure 5 is a block diagram of the direct memory access abnormality detection device of the second embodiment of the present invention. The direct memory access abnormality detection device 211 of Figure 4 can be implemented in the implementation manner of Figure 5, but the present invention does not limit the direct memory access abnormality detection device 211 to only be implemented in the manner of Figure 5. The direct memory access abnormality detection device 211 includes a plurality of hardware circuits, and the plurality of hardware circuits include logic and gates 2111, 2112, a counter 2113, a comparator 2114 and an interrupt flag generator 2115, wherein the logic and gates 2111, 2112 are electrically connected to the counter 2113, the logic and gate 2112 is electrically connected to the direct memory access device 22, and the comparator 2114 is electrically connected to the counter 2113, the interrupt flag generator 2115 and the direct memory access device 22.

The logic and gate 2111 is used for receiving the direct memory access abnormal detection enable signal ENCH and the clock CLK, and performing a logic and operation on the direct memory access abnormal detection enable signal ENCH and the clock CLK to generate a count trigger signal INC. The logic and gate 2112 is used for receiving the direct memory access abnormal detection enable signal ENCH and the work completion signal CP, and performing a logic and operation on the direct memory access abnormal detection enable signal ENCH and the work completion signal CP to generate a counter reset signal RST. The counter 2113 is used to receive the count trigger signal INC and the counter reset signal RST, count and generate a count value CNT according to the count trigger signal INC, and reset the count value CNT to zero according to the counter reset signal RST. The comparator 2114 is used to receive and compare the count value CNT with the count value threshold value CNTTH, and generate a comparison result as a direct memory access stop signal STP to the direct memory access device 12. The interrupt flag generator 2115 is used to generate an interrupt flag signal INTFL according to the direct memory access stop signal STP.

Furthermore, in addition to including a plurality of hardware circuits, the direct memory access abnormality detection device 211 may also have a processing module implemented by a software program. The processing module may be used to process the stopped direct memory access device 22 according to the interrupt flag signal, wherein the processing includes resetting the data processing circuit electrically connected to the direct memory access device 22, resetting the direct memory access device 22, disabling the direct memory access device 22, or notifying a processing personnel for processing.

Please refer to FIG. 4 to FIG. 6 , FIG. 6 is a flow chart of the direct memory access abnormality detection method of the second embodiment of the present invention. The direct memory access abnormality detection method is executed by the electronic system 2. In step S401, the direct memory access abnormality detection device 211 receives the direct memory access abnormality detection enable signal ENCH to enable the direct memory access abnormality detection device 211. In step S402, the direct memory access abnormality detection device 211 receives the count value threshold value CNTTH of the direct memory access device 22. Next, in step S403, the direct memory access test device 22 of the electronic system 2 is triggered. After the direct memory access test device 22 is triggered, in step S304, the direct memory access test device 22 operates to access data from the memory.

Then, in step S405, the direct memory access abnormality detection device 211 counts based on the clock CLK, and determines whether the generated count value CNT reaches the count value threshold value CNTTH. If the count value CNT reaches the count value threshold value CNTTH, then continue to execute step S408, otherwise, execute step S406. In step S408, the direct memory access abnormality detection device 211 generates a direct memory access stop signal STP to the direct memory access device 22 and an interrupt flag signal INTFL to stop the direct memory access device 22, and let the processing module process the abnormal direct memory access device 22. In step S406, the electronic system 2 determines whether the direct memory access device 22 has finished working. If so, the direct memory access device 22 finishes working and executes step S407. Otherwise, step S404 is executed, that is, the direct memory access device 22 continues to work. In step S407, the direct memory access abnormality detection device 211 receives the work completion signal CP of the direct memory access device 22 and resets the count value CNT to zero.

In summary, the direct memory access abnormality detection module, method and electronic system using the same provided by the embodiments of the present invention can allow the hardware circuit to detect and automatically stop the direct memory access device when a direct memory access abnormality occurs, thereby avoiding system crash or system shutdown, and achieving the goal of preventing abnormalities of multiple direct memory access devices at the same time (for example, multiple direct memory access devices overflow). In addition, the above-mentioned method of avoiding system crash or system shutdown In addition, in the embodiment of the present invention, the software program can be selectively intervened to report errors and perform processing, such as resetting the data processing circuit electrically connected to the direct memory access device 22 or the direct memory access device 22 itself, to release the abnormal state of the direct memory access device 22.

The present invention is disclosed in this article only with preferred embodiments. However, anyone familiar with the technical field should understand that the above embodiments are only used to describe the present invention and are not used to limit the scope of the patent rights claimed by the present invention. Any changes or substitutions that are equal or equivalent to the above embodiments should be interpreted as being included in the spirit or scope of the present invention. Therefore, the scope of protection of the present invention should be based on the scope defined by the following patent application.

1, 2: Electronic system 11, 21: Direct memory access abnormal detection module 111, 211: Direct memory access abnormal detection device 1111, 2111, 2112: Logical and gate 1112, 2114: Comparator 1113, 2115: Interrupt flag generator 12, 22: Direct memory access device 2113: Counter STP: Direct memory access stop signal BST: Burst signal INTFL: Interrupt flag signal ENCH: Direct memory access abnormal detection enable signal DADD: Upper address ADDTH: Upper address threshold value CLK: Clock CP: Work completion signal CNTTH: Count value upper limit CNT: Count value INC: Count trigger signal RST: Counter reset signal S301~S307, S401~S408: Steps

In order to make the above and other purposes, features, advantages and embodiments of the present invention more clearly understandable, the attached drawings are described as follows: Figure 1 is a block diagram of an electronic system using a direct memory access abnormality detection module of the first embodiment of the present invention; Figure 2 is a block diagram of a direct memory access abnormality detection device of the first embodiment of the present invention; Figure 3 is a flow chart of a direct memory access abnormality detection method of the first embodiment of the present invention; Figure 4 is a block diagram of an electronic system using a direct memory access abnormality detection module of the second embodiment of the present invention; Figure 5 is a block diagram of a direct memory access abnormality detection device of the second embodiment of the present invention; Figure 6 is a flow chart of the direct memory access abnormality detection method of the second embodiment of the present invention.

1: Electronic system

11: Direct memory access anomaly detection module

111: Direct memory access anomaly detection device

12: Direct memory access device

STP: Direct memory access stop signal

BST: Burst Signaling

INTFL: Interrupt flag signal

ENCH: Direct memory access abnormal detection enable signal

ADDTH: Upper address threshold

Claims (10)

A direct memory access abnormality detection module (11) comprises: one or more direct memory access abnormality detection devices (111), wherein the direct memory access abnormality detection device (111) is used to detect whether a direct memory access device (12) electrically connected thereto is abnormal; the direct memory access abnormality detection device (111) detects whether a direct memory access device (12) electrically connected thereto is abnormal; the direct memory access abnormality detection device (111) detects whether a direct memory access abnormality detection enable signal (ENCH) received by the direct memory access device (12) is abnormal; A burst signal (BST) of the device (12) generates an upper limit address (DADD) for the direct memory access device (12) to access a memory, and generates a direct memory access stop signal (STP) to the direct memory access device (12) and an interrupt flag signal (INTFL) according to the upper limit address (DADD) and a received upper limit address threshold value (ADDTH). The direct memory access abnormality detection module (11) as described in claim 1, wherein the direct memory access abnormality detection device (111) includes a plurality of hardware circuits, and the hardware circuits include: A logic and gate (1111) for receiving the burst signal (BST) and the direct memory access abnormality detection enable signal (ENCH), and performing a logic and operation on the burst signal (BST) and the direct memory access abnormality detection enable signal (ENCH) to generate the upper limit address (DADD) for the direct memory access device (12) to access the memory; A comparator (1112), electrically connected to the logic and gate (1111), for receiving and comparing the upper address (DADD) with the upper address threshold (ADDTH), and generating a comparison result as the direct memory access stop signal (STP) to the direct memory access device (12); and an interrupt flag generator (1113), electrically connected to the comparator (1112), for generating the interrupt flag signal (INTFL) according to the direct memory access stop signal (STP). The direct memory access abnormality detection module (11) as described in claim 2, wherein the direct memory access abnormality detection device (111) further includes: A processing module, which is implemented by a software program and is used to process the stopped direct memory access device (12) according to the interrupt flag signal (INTFL). A direct memory access abnormality detection module (21) comprises: one or more direct memory access abnormality detection devices (211), wherein the direct memory access abnormality detection device (211) is used to detect whether a direct memory access device (22) electrically connected thereto is abnormal; the direct memory access abnormality detection device (211) is enabled according to a received direct memory access abnormality detection enable signal (ENCH); when the direct memory access abnormality detection device (211) is enabled, it counts based on a received clock (CLK) to generate a count value (CNT); if the count value (CNT) reaches a count value threshold (CNTTH), the direct memory access abnormality detection device (211) will generate a direct memory access stop signal (STP) to the direct memory access device (22) and an interrupt flag signal (INTFL); when the direct memory access abnormality detection device (211) is enabled, if the direct memory access abnormality detection device (211) receives a work completion signal (CP) from the direct memory access device (22), the count value (CNT) is reset to zero. A direct memory access abnormality detection module (11) as described in claim 4, wherein the direct memory access abnormality detection device (111) includes a plurality of hardware circuits, and the hardware circuits include: A first logic and gate (2111) for receiving the direct memory access abnormality detection enable signal (ENCH) and the clock (CLK), and performing a logic and operation on the direct memory access abnormality detection enable signal (ENCH) and the clock (CLK) to generate a count trigger signal (INC); A second logic and gate (2112) is used to receive the direct memory access abnormal detection enable signal (ENCH) and the work completion signal (CP), and perform the logic and operation on the direct memory access abnormal detection enable signal (ENCH) and the work completion signal (CP) to generate a counter reset signal (RST); A counter (2113), electrically connected to the first logic and gate (2111) and the second logic and gate (2112), for receiving the count trigger signal (INC) and the counter reset signal (RST), generating the count value (CNT) by counting according to the count trigger signal (INC), and resetting the count value (CNT) to zero according to the counter reset signal (RST); A comparator (2114), electrically connected to the counter (2113), for receiving and comparing the count value (CNT) with the count value threshold value (CNTTH), and generating a comparison result as the direct memory access stop signal (STP) to the direct memory access device (12); and An interrupt flag generator (2115), electrically connected to the comparator (1112), is used to generate the interrupt flag signal (INTFL) according to the direct memory access stop signal (STP). The direct memory access abnormality detection module (21) as described in claim 5, wherein the direct memory access abnormality detection device (211) further comprises: A processing module, which is implemented by a software program and is used to process the stopped direct memory access device (22) according to the interrupt flag signal (INTFL). An electronic system (1, 2) comprising: A direct memory access anomaly detection module (11, 12) as described in any one of claims 1 to 6; The one or more direct memory access devices (12, 22); One or more data processing circuits electrically connected to the one or more direct memory access devices (12, 22) for accessing one or more data in the memory through the one or more direct memory access devices (12, 22). An electronic system (1, 2) as described in claim 7, wherein the data processing circuit includes an image data processing circuit, a sensor data processing circuit, an audio data processing circuit, a control data processing circuit, a packet data processing circuit or a peripheral device data processing circuit. A direct memory access abnormality detection method is performed by a direct memory access abnormality detection device (111), comprising: Receiving a direct memory access abnormality detection enable signal (ENCH) to enable the direct memory access abnormality detection device (111), and receiving an upper address threshold value (ADDTH) of a direct memory access detection device (12) electrically connected to the direct memory access abnormality detection device (111); After the direct memory access detection device (12) is triggered to make the direct memory access detection device (12) work, an upper limit address (DADD) for the direct memory access device (12) to access a memory is generated according to the direct memory access abnormal detection enable signal (ENCH) and a burst signal (BST) of the direct memory access device (12); and a direct memory access stop signal (STP) is generated to the direct memory access device (12) and an interrupt flag signal (INTFL) according to the upper limit address (DADD) and the upper limit address threshold value (ADDTH). A direct memory access abnormality detection method is performed by a direct memory access abnormality detection device (211), comprising: Receiving a direct memory access abnormality detection enable signal (ENCH) to enable the direct memory access abnormality detection device (211), and receiving a count value threshold value (CNTTH) of a direct memory access detection device (22) electrically connected to the direct memory access abnormality detection device (211); After the direct memory access detection device (22) is triggered to enable the direct memory access detection device (12) to work, counting is performed based on the received clock (CLK) according to the direct memory access abnormal detection enable signal (ENCH) to generate a count value (CNT); A direct memory access stop signal (STP) is generated to the direct memory access device (12) and an interrupt flag signal (INTFL) according to the count value (CNT) and the count value threshold value (CNTTH); and After the direct memory access detection device (22) is triggered to make the direct memory access detection device (12) work, the count value (CNT) is reset to zero according to the direct memory access abnormal detection enable signal (ENCH) and a work completion signal (CP) of the direct memory access detection device (22).

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