JP2020173602A - Information processing system - Google Patents

Abstract

To provide an information processing system including a device capable of preferentially transmitting transmission data with high priority.SOLUTION: An information processing system includes a first device and a second device for controlling an imaging device and a vehicle. The first device includes a processing unit, a memory, a memory controller having a plurality of ports and controlling memory access, and a register unit for storing a priority. The imaging device, the second device, and the processing unit are connected to any of the plurality of ports. The memory controller controls writing of data to the memory and reading of data from the memory based on the priority stored in the register unit. When an obstacle is detected based on image data photographed by the imaging device, the processing unit updates the register unit to make a priority of reading a port to which the second device is connected higher than a priority of writing of the port and generates control data for controlling the vehicle to transmit it to the second device.SELECTED DRAWING: Figure 2

Description

The present invention relates to an information processing system mounted on a vehicle or the like.

The vehicle is equipped with an information processing system in which a plurality of devices called ECUs (Electronic Control Units) are connected to each other via a bus. Each device sends and receives data to and from each other via a communication path, acquires data from sensors provided in the vehicle, performs processing based on various data, controls actuators provided in the vehicle, and controls each of the vehicles. The functions are shared and executed.

In such an information processing system, it is required to preferentially transmit and process urgent and important data. In connection with this, for example, the following techniques have been proposed.

In Patent Documents 1 and 2, in an information processing device connected to a plurality of sensors via their respective communication paths, the priority of each sensor is determined based on the data from each sensor, and the sensor having the higher priority is used first. It is disclosed that the communication path is arbitrated so that the data of the above is received preferentially.

Patent Document 3 describes, in an in-vehicle camera system for selectively displaying images of a plurality of camera modules on a display device, when the detection distance of a distance sensor included in each camera module is smaller than a predetermined distance, the image of the camera module is displayed. It is disclosed that the display device is preferentially displayed.

JP-A-2018-139120 Japanese Unexamined Patent Publication No. 2016-18295 Japanese Unexamined Patent Publication No. 2014-36400

In an information processing system, when devices connected to a plurality of communication paths transmit and receive data via these communication paths, writing of received data to the memory and reading of transmitted data from the memory occur. For memory writing and reading, a DMAC (Direct Memory Access Controller) provided for each communication path makes a write request or read request to the memory controller, and the memory controller mediates the write request or read request from each DMAC. , It is done by accessing the memory according to the arbitration result.

When arbitration is performed in units of communication paths (buses) as in Patent Documents 1 and 2 in order to preferentially transmit data with high urgency and importance, in general, the transmission direction and reception of data in the communication path are performed. The order priority is the same. Therefore, it is necessary to preferentially transmit the transmission data from the device, and even if the transmission data generation processing is completed, if there is a lot of reception data from the same communication path, the reception data is written to the memory. Therefore, the process of reading the transmission data from the memory is made to wait, and the transmission data may not be preferentially transmitted.

The present invention has been made in view of the above problems, and an object of the present invention is to provide an information processing system including a device capable of preferentially transmitting high-priority transmission data to another device.

In order to solve the above problems, one aspect of the present invention is an information processing system mounted on a vehicle and including a first device, at least an image pickup device, and a second device for controlling the vehicle. , A processing unit, a memory, a memory controller having a plurality of ports and controlling the writing and reading of the memory, and storing the priority determined for each writing to the memory and reading from the memory of the plurality of ports. The imaging device, the second device, and the processing unit are connected to any of the plurality of ports, including the register unit, and the memory controller is used for each of the plurality of ports based on the priority stored in the register unit. Controls the writing of data to the memory based on the write request issued and the reading of data from the memory based on the read request issued to each of the plurality of ports, and the processing unit controls the reading of the data from the memory based on the read request issued for each of the plurality of ports. Image data taken by the image pickup device is acquired, processing is performed based on the acquired image data, and when an obstacle is detected as a result of the processing, control data for controlling the vehicle is generated, and the control data is generated via the memory. While transmitting to the two devices, the processing unit writes the read priority of the port to which the second device is connected, which is stored in the register unit, to the port to which the second device is connected, while the processing unit detects an obstacle. It is an information processing system that has a higher priority than.

According to the present invention, it is possible to provide an information processing system including a device capable of preferentially transmitting transmission data having a high priority to another device.

Configuration diagram of the information processing system according to the first and second embodiments of the present invention. A flowchart showing the processes according to the first and second embodiments of the present invention. The figure which shows the example of the initial value of the priority setting which concerns on 1st Embodiment of this invention. The figure which shows the example of the value at the time of changing the priority setting which concerns on 1st Embodiment of this invention. The figure which shows the example of the initial value of the priority setting which concerns on 2nd Embodiment of this invention. The figure which shows the example of the value at the time of changing the priority setting which concerns on 2nd Embodiment of this invention.

(First Embodiment)
In the information processing system according to the present invention, when data to be transmitted preferentially is transmitted, the priority of the read control of the port for reading the data among the ports of the memory controller is set to the write control of the same port. Higher than the priority of. As a result, data reading is prioritized over writing on the corresponding port, and even if there is a lot of data received from the same port, its influence can be suppressed and data that should be preferentially transmitted can be transmitted earlier. it can.

<Composition>
FIG. 1 shows the configuration of the information processing system 1 according to the present embodiment. The information processing system 1 is mounted on the vehicle. The information processing system 1 includes a first device 101, and other devices such as a second device 204 and imaging devices 201, 202, and 203. The first device 101 is an ECU that executes a driving assistance function as an example. The first device 101 is connected to the image pickup devices 201, 202, 203, and the second device 204 via their respective communication paths at any of the ports of the memory controller 140 described later. The imaging devices 201, 202, and 203 image the surroundings of the vehicle.

The first device 101 receives the image data taken by the image pickup devices 201, 202, and 203 via each communication path, and based on the image data, determines the presence or absence of obstacles around the vehicle and the distance from the obstacles. calculate. When the first device 101 detects that there is an obstacle around the vehicle, the first device 101 generates control data for controlling the traveling direction and acceleration / deceleration of the vehicle in order to avoid the obstacle. The second device 204 is an ECU that controls the brake as an example, and the first device 101 transmits, for example, control data instructing the brake operation to the second device 204 to operate the brake, thereby causing the user to operate the brake. Support driving. Alternatively, the second device 204 is an ECU that controls the power steering as an example, and the first device 101 transmits, for example, control data instructing the steering operation to the second device 204 to execute the steering operation. Then, the user's driving may be assisted. In the present embodiment, it is assumed that the control data to be transmitted to the second device 204 is the data to be transmitted preferentially.

The first device 101 is an integrated circuit called an integrated circuit SOC110 (System On Chip), a CAN transceiver 102 which is a transceiver conforming to a CAN (registered trademark) communication standard, a NOR flash memory 105, and a NAND flash memory 106. A memory 107, which is a RAM, and a power supply circuit 104 that supplies power to each of these parts are provided.

The SOC 110 includes a processing unit 109 that is a CPU (Central Processing Unit), a memory controller 140 that controls access to write and read of the memory 107, a register unit 108 that includes registers for setting operations of the memory controller 140, and buffers 111 to 115. , DMAC 121-124, and a relay unit 130. The memory controller 140 has ports 141 to 143, each having a buffer. The register unit 108 stores the priority of writing to the memory 107 and the priority of reading from the memory 107 for each of the ports 141 to 143. The priority stored in the register unit 108 can be changed by the processing unit 109.

Here, the control of writing and reading of the memory 107 will be described. The processing unit 109 issues a data read request or a write request to port 141 of the memory controller 140 by designating an address, for example, as necessary for processing execution. When the data received from another device is stored in the buffers 111 to 114, respectively, the DMACs 121 to 124 issue a write request to the received data to the ports 142 and 143 of the memory controller 140 by designating an address, for example. Further, the DMACs 121 to 124 specify, for example, addresses to the ports 142 and 143 of the memory controller 140 based on conditions such as control from the processing unit 109 and other units and a period specified in advance by the processing unit 109. Issue a read request. The memory controller 140 receives these write requests and read requests, and controls access to the memory 107 based on the write and read priorities of the ports 141 to 143 set in the register unit 108. That is, for write requests and read requests issued to each of the plurality of ports 141 to 143, the order is determined so that the one with the highest priority comes first, and data is written and read in the determined order. To execute.

Some specific examples will be described. When the image data received from the image pickup apparatus 201 is stored in the buffer 111, the DMAC 121 issues a write request to the port 142, and the image data is transmitted to the memory controller 140 via the relay unit 130 and the port 142. Written to memory 107. When the image data received from the image pickup apparatus 202 is stored in the buffer 112, the DMAC 122 issues a write request to the port 142, and the image data is transmitted to the memory controller 140 via the relay unit 130 and the port 142. Written to memory 107. When the image data received from the image pickup apparatus 203 is stored in the buffer 113, the DMAC 123 issues a write request to the port 142, and the image data is transmitted to the memory controller 140 via the relay unit 130 and the port 142. Written to memory 107.

When the processing unit 109 requires image data for processing, a read request is issued to the port 141, the image data written in the memory 107 is read by the memory controller 140, and the processing unit is used via the port 141. Provided to 109. The processing unit 109 performs processing based on the image data, and when it is detected that there is an obstacle around the vehicle as a result of the processing, the processing unit 109 generates control data for avoiding the obstacle. The processing unit 109 issues a control data write request to the port 141, and the control data is transmitted to the memory controller 140 via the port 141 and written to the memory 107.

The DMAC 124 issues a read request to the port 143 based on a read instruction from the processing unit 109 or the like or a condition specified in advance, and the control data written in the memory 107 is read by the memory controller 140. , Stored in buffer 114 via port 143. When the control data is stored in the buffer 114, the CAN transceiver 102 transmits the control data to the second device 204.

Data transmission / reception between the processing unit 109 and the imaging devices 201-203 and data transmission / reception between the processing unit 109 and the second device 204 are performed by writing the data to the memory 107 and reading the data from the memory 107. It is done through. In addition to the above-mentioned image data reception and control data transmission, data transmission / reception includes transmission of commands for controlling the image pickup devices 201 to 203, and steering and power provided by the vehicle from the second device 204. There is no limitation, such as reception of the state of the steering device.

The NOR flash memory 105 and the NAND flash memory 106 store various data such as a program executed by the processing unit 109 to perform the above-mentioned processing and control of each unit.

Regarding the internal configuration of the first device 101 and the configuration of the connected device, among the ports to which the communication paths from other devices are connected, the port for reading predetermined data having a high priority has a higher priority. It may be different from the one described above as long as it is different from other ports for writing and reading data that are not expensive. For example, the number of image pickup devices may not be three, the relay unit 130 may not be provided, and the image data received from each image pickup device may be connected to different ports of the memory controller 140. Further, the second device 204 communicates with the first device 101 in conformity with the CAN standard via the CAN transceiver 102, but the Ethernet PHY is a transceiver conforming to the communication standard of the Ethernet (registered trademark) method. (Physical Layer Chip) may be used to communicate with the first device 101 in accordance with the Ethernet standard. Further, another device may be connected to each communication path to which the image pickup devices 201 to 203 and the second device 204 are connected. The first device 101 may include more buffers and DMACs, the memory controller 140 may have more ports, and the first device 101 may be connected to yet another communication path.

<Processing>
The processing according to this embodiment will be described below. FIG. 2 shows a flowchart showing an example of processing. This process is executed, for example, when the driving assistance mode is started when the user performs an operation for enabling the driving assistance function.

(Step S101): The processing unit 109 of the first device 101 transmits a command instructing image pickup to the image pickup devices 201, 202, 203 to start imaging around the vehicle. The image data obtained by imaging is sequentially received by the first device 101.

(Step S102): The processing unit 109 of the first device 101 performs a predetermined recognition process on an object around the vehicle based on the image data.

(Step S103): When the processing unit 109 of the first device 101 detects another vehicle, a person, or the like within 5 m in the traveling direction from the vehicle, it detects it as an obstacle that may collide. The processing unit 109 acquires information such as the traveling speed of the vehicle and the type of traveling road such as a general road or an expressway from various sensors and other devices provided in the vehicle, and determines the risk of collision based on these information. You may. If the processing unit 109 detects an obstacle, the process proceeds to step S104, and if no obstacle is detected, the processing unit advances the process to step S106.

(Step S104): The processing unit 109 of the first device 101 registers so that the read priority of the port 143 of the memory controller 140 used for reading the control data described later is higher than the write priority of the same port 143. The value of the register of unit 108 is changed. 3 and 4 show an example of writing and reading settings for each port of the memory controller 140. FIG. 3 shows the settings in the initial state, and FIG. 4 shows the settings changed by the processing of this step. FIG. 4 shows the changed part by hatching. If this step has already been executed and the register value of the register unit 108 has been changed from the initial value, no particular processing is performed.

(Step S105): The processing unit 109 of the first device 101 generates control data for controlling the vehicle in order to avoid obstacles. The generated control data is transmitted to the second device 204. After this process, the process proceeds to step S102 and the process is repeated.

(Step S106): The processing unit 109 of the first device 101 changes the value of the register of the register unit 108 so that the read priority of the port 143 of the memory controller 140 is set to the initial value. If the register value of the register unit 108 is the initial value, no particular processing is performed. After this process, the process proceeds to step S102 and the process is repeated.

<Effect>
In the present embodiment, when the control data to be transmitted preferentially is transmitted, the priority of the read control of the port 143 of the memory controller 140 that reads the control data for transmission to the transmission destination second device 204 is set. Higher than the write priority of port 143. As a result, the control data can be read out to the port 143 even when a large amount of data is received from the second device 204 or another device (not shown) connected to the same communication path as the second device 204. It is performed preferentially, and it is possible to suppress an increase in the time required from the issuance of the read request to the read. As a result, the functions of the information processing system 1 such as driving assistance can be suitably realized. As shown in FIGS. 3 and 4, the time between the processing unit 109 and the memory 107 is that the processing unit 109 waits for the completion of writing the data to the memory 107 and reading the data from the memory 107. The write or read priority of the port 141 to which the processing unit 109 is connected may always be kept high so that the processing does not become long and the processing is not delayed. Further, as shown in FIG. 4, the writing and reading priorities of the ports 142 other than the port 143 for reading the control data having a high priority and the port 141 to which the processing unit 109 is connected are also at least when the control data is transmitted. When the priority is lower than the read priority of the port 143, the time required from the issuance of the control data read request to the read can be suppressed.

(Second Embodiment)
In the present embodiment, the method of changing the write and read priority of the ports 141 to 143 of the memory controller 140 is different from that of the first embodiment. In the first embodiment, the processing unit 109 is changed by setting the register of the register unit 108, but in the present embodiment, the processing unit 109 or the DMAC 121-124 instead makes a write request and a read request each time. , By designating each port 141 to 143 of the memory controller 140. Items different from those of the second embodiment will be described below, and description of similar items will be omitted.

In the present embodiment, the processing unit 109 specifies the read / write priority of the port 141 of the memory controller 140. In addition, DMAC 121 to 123 specify the read and write priority of the port 142. The DMAC 124 specifies the read and write priority of port 143. The DMAC 124 specifies the read and write priority of port 143. Further, the control of the priority designation by the DMAC 121 to 124 is performed by the processing unit 109 or based on the instruction received from the processing unit 109 in advance by each of the DMAC 121 to 124.

The process according to the present embodiment is a modification of the process of steps S104 and S106 in the first embodiment as follows.

In the present embodiment, in step S104, the processing unit 109 of the first device 101 sets the priority of the read request of the DMAC124 to the port 143 of the memory controller 140 higher than the priority of the write request of the DMAC124. 5 and 6 show an example of writing and reading settings for each port of the memory controller 140. FIG. 5 shows the settings in the initial state, and FIG. 6 shows the settings changed by the process of this step. FIG. 6 shows the changed part by hatching.

In the present embodiment, in step S106, the processing unit 109 of the first device 101 sets the priority of the read request as the initial value in the read request of the DMAC 124 to the port 143 of the memory controller 140.

The priority may be specified by notifying the priority together with each request each time the processing unit 109 and the DMAC 121-124 make a write request and a read request to the ports 141 to 143 of the memory controller 140. The memory controller 140 holds the priority specified once in this way for each of the processing unit 109 and the DMAC 121 to 124 until it is newly specified, and according to the request source of the write request and the read request. You may specify the priority. In addition to distinguishing between writing and reading, the processing units 109 and DMAC 121 to 124 may change the priority according to the type of data, the source of data, and the device of the destination. Thereby, the data to be preferentially transmitted can be specified in a more limited manner. For example, when issuing a read request to the port 143, the DMAC 124 specifies a high priority only when it is high control data addressed to the second device 204, and a low priority for other data having a low priority. May be specified.

<Effect>
In the present embodiment, as in the first embodiment, when the control data to be preferentially transmitted is transmitted, the DMAC 124 that requests the reading of the control data is set to the port 143 for reading the control data of the memory controller 140. On the other hand, control is performed so that control data is read with a higher priority than writing. As a result, even when a large amount of data is received from the second device 204 or another device (not shown) connected to the same communication path as the second device 204 to the port 143, the read request can be issued. It is possible to suppress an increase in the time required for reading. As a result, the functions of the information processing system 1 such as driving assistance can be suitably realized. In addition to the distinction between writing and reading, if the priority is changed according to the type of data and the distinction between the data source and destination devices, the control data can be specified more limitedly. Even if the data is read from the port 143, the priority of reading data other than the control data can be lowered, so that the control data can be read with higher priority.

Although each embodiment of the present invention has been described above, the present invention describes not only the information processing system but also a method and a program executed by a computer provided in each part of the information processing device and the information processing system such as the above-mentioned first device. It can be regarded as a computer-readable non-temporary storage medium that stores this, a vehicle equipped with an information processing system, and the like. Further, the present invention can be applied to an information processing system other than the information processing system mounted on the vehicle.

The present invention is useful for an information processing system mounted on a vehicle or the like.

1 Information processing system 101 First device 102 CAN transceiver 104 Power supply circuit 105 NOR flash memory 106 NAND flash memory 107 Memory 108 Register unit 109 Processing unit 111-115 Buffer 121-124 DMAC
130 Relay unit 140 Memory controller 141-143 Ports 201-203 Imaging device 204 Second device

Claims (1)

An information processing system mounted on a vehicle and including a first device, at least an image pickup device, and a second device for controlling the vehicle.
The first device has a processing unit, a memory, a plurality of ports, a memory controller that controls writing and reading of the memory, and each writing of the plurality of ports to the memory and reading from the memory. Including a register part that stores the priority specified in
The imaging device, the second device, and the processing unit are connected to any of the plurality of ports.
The memory controller writes data to the memory based on a write request issued to each of the plurality of ports based on the priority stored in the register unit, and writes data to the memory based on a write request issued to each of the plurality of ports, and each of the plurality of ports. Controls the reading of data from the memory based on the read request issued to
The processing unit acquires image data captured by the imaging device via the memory, performs processing based on the acquired image data, and controls the vehicle when an obstacle is detected as a result of the processing. Control data is generated and transmitted to the second device via the memory.
While the processing unit detects the obstacle, the processing unit sets the read priority of the port to which the second device is connected, which is stored in the register unit, of the port to which the second device is connected. An information processing system that has a higher priority than writing.

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