JP2002197050A - System, method and unit for arbitration control - Google Patents

Abstract

PROBLEM TO BE SOLVED: To allocate use permission with good balance for requests to use a shared resource from a plurality of requesters. SOLUTION: Requesters 80 are provided with a use request control part 10A which receives a use request from a requester 80 and which sends the use request to an arbitrating circuit 80 when receiving a specific permission signal and a counter part 10B which sends the permission signal to the use request control part 10A in a permission period according to characteristics of the requester 80 and which does not send it in a non-permission period to send the permission signal at a specific frequency, so the number of times of sending the use request from each requester 80 to the arbitrating circuit 90 by the use request control part 10A is controlled to the number of times specified for the respective requesters and the use request from each requester 80 is transmitted to the arbitrating circuit 90 at the proper number of times corresponding to the characteristics of each requester 80.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an arbitration control system, an arbitration control method, and an arbitration control device, and more particularly, to a plurality of requesters for transmitting a use request for a shared resource shared among a plurality of devices, An arbitration control system configured to include an arbitration unit that performs arbitration by selecting a requester that permits use of the shared resource according to the received use request; an arbitration control method realized by the arbitration control system; And an arbitration control device that performs arbitration control.

[0002]

2. Description of the Related Art Conventionally, as shown in a system for transferring image data from a controller board of an electrophotographic printer to a print engine, there are requesters that need to transfer data within a fixed time and requesters that do not have a prescribed time. In a system arranged on a common bus, Japanese Patent Application Laid-Open No. Hei 9 (1999) discloses a technique in which a function of changing the priority order of use requests is implemented in the arbitration means itself in order to secure a predetermined data transfer time interval to the former requester. -91194.

[0003] For the same purpose, Japanese Patent Laid-Open Publication No. 6-22145 discloses a technique of grouping requesters that need to complete data transfer within a certain period of time and requesters with no specified time according to their priorities. Is disclosed.

[0004]

However, in the technique disclosed in Japanese Patent Application Laid-Open No. 9-91194, the number of requesters transmitting a request for use of a bus is increased, so that the combination of the requesters has a degree of freedom. In addition, an enormous combination circuit and a complicated mode setting circuit for prioritization are required.

In the technique disclosed in the above-mentioned Japanese Patent Application Laid-Open No. 6-22145, when a system is configured by grouping and hierarchization in order to reduce a huge number of combinations,
A low-speed requester that does not need real-time performance unnecessarily issues a use request, which causes an inconvenience such as hindering data transfer of a requester that requires high-speed performance. For this reason, a requester that needs to complete data transfer within a certain period of time and a requester that does not have a specified time are mixed on one bus, and the data is transferred under an appropriate priority according to the characteristics of each requester. There is a problem that it is difficult to control the transfer.

For example, a PCI (Peripheral Component)
In a system connected by an interconnect, since there is only one request signal that can be requested from each board to the arbitration circuit, a requester that requires completion of data transfer within a fixed time and a requester that does not have a specified time are included in the same board. When the request signals are mixed, the arbitration circuit must be set as a requester that needs to complete the data transfer within a certain time. Therefore, a request from a requester who lives in the board and has no specified time is handled in the same way, and prioritization as desired cannot be performed.

As an example, in the hierarchical arbitration control system shown in FIG. 10, when it is desired to assign a priority A>B> C among requesters A, B and C, an arbitration circuit ARB1 requires a bus use request signal. Line (hereinafter referred to as "REQ")
Priority of 12 and 13 is set to REQ12> REQ13
The arbitration circuit ARB2 sets REQ21,
23 need to be set so that REQ21> REQ23. However, in this setting, the priority among the requesters A, B, and C is inevitably A>C>
It becomes B and I can't give priority to what I want.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problem, and is an arbitration control capable of allocating usage permission in a balanced manner to usage requests from a plurality of requesters transmitting a usage request for a shared resource. It is an object to provide a system, an arbitration control method, and an arbitration control device.

[0009]

To achieve the above object, an arbitration control system according to the present invention comprises a plurality of requesters for transmitting a use request for a shared resource shared among a plurality of devices; Control means for transmitting the received use request at a predetermined frequency set for the requester that transmitted the use request, and a requester for permitting use of the shared resource according to the received use request. Arbitration means for performing arbitration by selecting.

The present invention can also be considered as the invention of the following arbitration control method. That is, the arbitration control method according to the present invention selects a plurality of requesters transmitting a use request for a shared resource shared by a plurality of devices, and a requester permitting use of the shared resource according to the received use request. An arbitration control method in an arbitration control system including arbitration means for performing arbitration by performing arbitration control means, wherein arbitration control means for controlling arrival of a use request to the arbitration means is provided in the arbitration control system, A receiving step of receiving the use request by the arbitration control unit, and a transmission step of transmitting the received use request at a predetermined frequency set for the requester that transmitted the use request by the arbitration control unit. It is characterized by having.

Further, the present invention can be considered as the invention of the following arbitration control device. That is, the arbitration control device according to the present invention selects a plurality of requesters that transmit a use request for a shared resource shared among a plurality of devices, and a requester that permits use of the shared resource according to the received use request. Arbitration means for performing arbitration by providing the arbitration control system, the arbitration control system configured to receive the use request, and receive the use request at a predetermined frequency set for the requester that transmitted the use request. The use request is transmitted.

The arbitration control system, arbitration control method and arbitration control device according to the present invention have substantially the same means for solving the problems. Therefore, the arbitration control system according to the invention will be described below.

In the arbitration control system according to the present invention, the request for use of the shared resource transmitted by the requester is not directly transmitted to the arbitration means but received by the control means (corresponding to the arbitration control device according to the present invention). The control means transmits a use request at a predetermined frequency set for the requester. The arbitration unit that receives the use request performs arbitration by selecting a requester that permits use of the shared resource according to the use request.

Here, the frequency is defined, for example, by defining a period during which the control means transmits a use request and a period during which the request is not transmitted, and transmitting the request only during the transmission period. It means the average number of transmissions (the average number of times a use request is transmitted to the arbitration means).

As described above, according to the present invention, the operation of transmitting the received use request is controlled by the control means so as to have a frequency set for the requester that has transmitted the use request, so that the operation is performed within a predetermined time. Even when a requester that requires data transfer completion and a requester with no specified time coexist, a use request is transmitted at a frequency corresponding to the characteristics of each requester (the use necessity of shared resources). As a result, the use permission is allocated in a balanced manner by the arbitration means in response to the use request from the plurality of requesters for the shared resource. In addition, the above control is not realized by the operation of the arbitration means, but is realized by a control means different from the arbitration means, so that the use permission is well-balanced without depending on the configuration or function of the arbitration means. Can be allocated.

The control means receives the use request,
It can be configured to include a use request control unit that transmits the received use request when a predetermined permission signal is received, and a frequency adjustment unit that transmits the permission signal at a predetermined frequency. In this case, the use request control unit transmits the received use request when the use request control unit receives the use request and subsequently receives the permission signal transmitted at a predetermined frequency by the frequency adjustment unit. With this configuration, the frequency of transmitting the use request can be controlled by controlling the frequency of transmission of the permission signal by the frequency adjusting unit.

At this time, it is preferable that the frequency of transmission of the permission signal by the frequency adjusting means can be dynamically changed. In this case, the frequency of transmission of the permission signal is determined according to the use necessity of the shared resource based on the use status of each requester. By dynamically changing the frequency of transmission of the permission signal by the adjusting means, it is possible to appropriately control the frequency of transmitting the use request according to the necessity of use.

As means for dynamically changing the frequency of transmission of the permission signal by the frequency adjustment means, a period for setting a permission period for transmitting the permission signal and a non-permission period for not transmitting the permission signal by the frequency adjustment means. It is desirable to further provide setting means. Thereby, for example, even when a requester that requires data transfer completion within a certain time and a requester without a time specification are mixed, the latter requester without a time specification can be set to a permission period by the period setting means. By setting the non-permission period longer, during the longer non-permission period, the use request from the requester that needs to complete the data transfer within the fixed time of the former is affected by the use request from the latter requester. Therefore, the object of completing the data transfer within a fixed time in the former requester can be achieved.

Here, the permission period and the non-permission period may be individually set. However, in order to simplify the configuration, a single period length is set, and the single period length sets the permission period and the non-permission period. The permission period may be alternately repeated.

Further, it is desirable to further provide a waiting period setting means for setting a waiting period from the time when one permission signal is transmitted by the frequency adjusting means to the time when the next permission signal can be transmitted. During this waiting period, the use request is not transmitted by the use request control means, so that the requester that has transmitted the use request cannot transmit the next use request and enters a standby state. Therefore, even when a requester that needs to complete data transfer within a certain period of time and a requester without a specified time are mixed, a predetermined standby period is set by the standby period setting means for the latter requester without a specified time. By doing so, during the standby period, the use request transmitted by the requester that needs to complete the data transfer within the fixed time of the former is not affected by the use request transmitted by the latter requester. The requester can achieve the purpose of completing data transfer within a certain time.

Further, the frequency adjusting means may control the transmission operation of the permission signal in synchronization with the external signal.
Thus, for example, when a requester such as a printer that requires data transfer completion within a certain period of time and a requester that does not have a prescribed time period are mixed, the frequency adjusting means can use the former requester (for example, a printer or the like) to transmit a shared resource (for example, a printer). (E.g., bus) while receiving an external signal indicating that the requester is busy, by controlling the latter to not transmit a permission signal to the latter requester, so that the permission signal transmission operation is performed according to the characteristics of each requester. It is possible to perform appropriate control.

The control means (corresponding to the arbitration control device according to the present invention) may be provided in common for a plurality of requesters, or may be provided for each requester. When provided for each requester, the control means may be constituted by an interval timer capable of adjusting the timing of transmitting a use request from the requester to the arbitration means. In this configuration, the interval timer is provided for each requester With such a relatively simple configuration, there is an advantage that transmission control of the use request to the arbitration unit as described above can be realized, and the configuration of the arbitration control system can be simplified.

The following configuration may be adopted in consideration of the retry sequence in the bus protocol. That is, the control unit further includes a non-permission state invalidating unit that temporarily invalidates a non-permission state in which the permission signal is not transmitted,
The non-permission state invalidation means transmits an invalidation signal when a predetermined condition is satisfied, and the use request control means having received the invalidation signal transmits a use request regardless of the state of the permission signal. It is desirable.

In the case of a retry sequence operation in the bus protocol, the requester must immediately start the same access. Here, with the above configuration,
When the non-permission state invalidating means satisfies a predetermined condition (for example, a condition such as detection of the start of the retry sequence operation), the invalidation signal is transmitted, and the use request control means transmits the invalidation signal. Upon reception, a use request is transmitted regardless of the state of the permission signal. Thus, regardless of the state of the permission signal, the use request from the requester can be immediately transmitted to the arbitration means, and there is an advantage that the retry sequence operation and the like can be flexibly and smoothly responded.

[0025]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. In the description of the drawings, the same elements will be denoted by the same reference symbols, without redundant description.

(First Embodiment) First, a first embodiment according to the present invention will be described.
An embodiment will be described. FIG. 1 is a configuration diagram of an information processing system 1 according to the first embodiment. The information processing system 1 shown in FIG. 1 assumes a controller of a printer for printing an image on paper, and connects a memory controller 19, a system memory 20, a CPU 30, and other external devices to a system bus. (Registered trademark) interface unit 40, a compressor 50, an HDD interface unit 60 for connecting a hard disk drive (HDD) 61 to a system bus, and an I / O for connecting a printer engine (IOT) 71 to a system bus.
An OT interface unit 70 is provided.

Memory controller 19, CPU 30, Ethernet interface unit 40, compressor 50, HDD
The interface unit 60 and the IOT interface unit 70 are connected to each other via a system bus. The CPU 30 accesses the system memory 20 via the memory control device 19 in units of 32 bytes.
Each of the Ethernet interface unit 40, the compressor 50, the HDD interface unit 60, and the IOT interface unit 70 has a DMA function.

Ethernet interface unit 40
Receives image data from an external device and stores the received image data in the system memory 20 via the system bus and the memory control device 19. The compressor 50 is
Image data is received from the system memory 20 via the system bus and the memory control device 19 and compressed, and the compressed image data is stored in the system memory 20. The HDD interface unit 60 transfers image data between the hard disk drive 61 and the system memory 20 via the system bus and the memory control device 19. The IOT interface unit 70 receives the compressed image data from the system memory 20 via the system bus and the memory controller 19, decompresses the compressed image data, and sends it to the printer engine 71. The printer engine 71 prints an image on a sheet based on the image data received from the IOT interface unit 70. Note that the system memory 20 stores the SDRA
M. Address signals, various control signals, and clock signals are input from the memory control device 19 to the system memory 20.

FIG. 2 shows a structural diagram relating to the arbitration process in the information processing system 1 shown in FIG. 1. A plurality of requesters shown in FIG. 2 are devices capable of issuing a bus use right request, that is, the memory shown in FIG. Control device 19, CPU 30,
Ethernet interface unit 40, compressor 50,
It corresponds to one of the HDD interface unit 60 and the IOT interface unit 70, and includes a plurality of arbitration circuits (AR
B1, ARB11, ARB14, ARB2)
Although omitted in FIG. 1, each of these requesters is connected to a bus use right request signal line REQ and a bus use right permission notification line ACK.
Connected by

The structure relating to the arbitration processing shown in FIG.
Below the level 1 arbitration circuit ARB1, three level 2 arbitration circuits ARB2, ARB11 and ARB14 are arranged,
The requesters 21 and 2 are arranged below the arbitration circuit ARB2.
2, 23 and 24 are arranged.

In the first embodiment, as shown in FIG.
Each requester is provided with an interval timer 10 for adjusting the timing of transmitting a use request from the requester to the arbitration circuit.

Here, the configuration of the interval timer 10 will be described with reference to FIG. Here, each requester in FIG. 2 is collectively referred to as a requester 80, and each arbitration circuit is generally referred to as an arbitration circuit 90.

As shown in FIG. 3A, the interval timer 10 receives the use request from the requester 80, and when the permission signal from the counter unit 10B described later is high, the interval timer 10 arbitrates the received use request. A request control unit 10A for transmitting a permission signal to the use request control unit 10A, a permission counter value register 10C storing a permission counter value for monitoring the elapse of a permission period for transmitting a permission signal (giving a permission signal high) to the use request control unit 10A, FIG. 3B shows a non-permission counter value register 10D that stores a non-permission counter value for monitoring the elapse of a non-permission period in which a permission signal is not transmitted to the use request controller 10A (the permission signal is low). Thus, the permission signal is transmitted to the use request control unit 10A for the time set by the permission counter value, and the permission signal is transmitted by the permission signal for the time set by the non-permission counter value. It is configured to include a counter portion 10B to over. The permitted counter value and the non-permitted counter value can be corrected by the CPU 30 at any time according to the configuration of the devices connected to the system and the operation status.

Next, as an operation of the first embodiment, FIG.
The operation of the interval timer 10 of each requester 80 and the prioritization of each requester 80 in the entire information processing system 1 will be described with reference to FIGS.

The counter section 10 of the interval timer 10
In B, the processing shown in FIG. 4 is executed. That is, the counter unit 10B fetches the permission counter value from the permission counter value register 10C (step 102), and transmits a permission signal to the use request control unit 10A until the set time based on the fetched permission counter value elapses (step 104, 1
06).

When the use request control unit 10A receives a bus use request from the requester 80 in this time zone H1 (see FIG. 3B), the permission signal from the counter unit 10B is high. The unit 10A immediately transmits the use request to the arbitration circuit 90. Then, the arbitration circuit 90
Arbitration is performed, and a use permission is transmitted from the arbitration circuit 90 to the requester 80 via the use request control unit 10A. The requester 80 that has received the use permission uses a desired resource using the bus based on the use permission.

As described above, when the time period H1 (set time based on the permission counter value) in which the use request from the requester 80 is immediately transmitted to the arbitration circuit 90 elapses, an affirmative determination is made in step 106 of FIG. 4 and the counter unit 10B Fetches the non-permission counter value from the non-permission counter value register 10D (step 108), and stops transmission of the permission signal until the set time based on the fetched non-permission counter value elapses, that is, sets the permission signal low (step 108). 110, 11
2).

When the use request control unit 10A receives a bus use request from the requester 80 during this time period H2 (see FIG. 3B), the permission signal from the counter unit 10B is low. The unit 10A holds the use request without transmitting it to the arbitration circuit 90. That is, since the permission signal remains low until the set time based on the non-permission counter value elapses, the use request from the requester 80 is held by the use request control unit 10A and is not transmitted to the arbitration circuit 90.

When the set time based on the non-permission counter value has elapsed, an affirmative determination is made in step 112 of FIG. 4, and the process returns to step 102, where the counter unit 10B takes in the above-mentioned permission counter value (step 102) and uses the permission signal. The transmission to the request control unit 10A (step 104) is executed again.

As a result, the use request control unit 10A allows the requester 8 during the non-permission period (while the permission signal is low).
The use request received from 0 is transmitted to the arbitration circuit 90 after the non-permission period ends. Then, arbitration is performed by the arbitration circuit 90, and the arbitration circuit 90 transmits a use permission to the requester 80 via the use request control unit 10A.
The requester 80 that has received the use permission can use a desired resource by using the bus based on the use permission.

As described above, the control is performed so that the use request from the requester 80 is not transmitted to the arbitration circuit 90 during the non-permission period. Therefore, in the hierarchical arbitration control system shown in FIG. 2, the priority order among the requesters A, B, and C is set to A.
When it is desired to add>B> C, the following can be set as an example. That is, the arbitration circuit ARB1 sets the priority of the bus use right request signal lines (REQ) 12, 13 so that REQ12 = REQ13, and the arbitration circuit ARB2 sets the priority of REQ21, 23 to RE.
Set so that Q21 = REQ23. Then, the interval timer 10 in each of the requesters A, B, and C is set so that the permission period is 0.8t and the non-permission period is 0.2t in A in the same time zone t as shown in FIG. , B, the permission period is 0.5t and the non-permission period is 0.5t
The priority order among the requesters A, B, and C is set as A>B> C by setting the permission period to be 0.2 t and the non-permission period to be 0.8 t in C. be able to.

As described above, according to the first embodiment, the arbitration control system having a plurality of layers is set by setting the permitted counter value and the non-permitted counter value in the interval timer 10 of each requester 80 in accordance with the priority order to be set. However, it is possible to set a desired priority for each requester. As a result, it is possible for the arbitration circuit 90 to allocate the use permission in a well-balanced manner to the use requests from the plurality of requesters 80 for the bus. Further, the above control is not realized by the operation of the arbitration circuit 90, but is realized by the interval timer 10 different from the arbitration circuit 90, so that the control can be performed without depending on the configuration and functions of the arbitration circuit 90. Permission can be allocated in a balanced manner. Further, the CPU 30 can input corrected values for the permission counter value and the non-permission counter value at any time, and the latest permission counter value and the latest non-permission counter value are fetched in steps 102 and 108 in FIG. Since it can be dynamically changed, it is possible to flexibly and promptly cope with a change in the usage state such as performing a long-time printing process in the IOT 71 such as a printer.

(Second Embodiment) In the second embodiment, FIG.
As shown in (a), since the configuration of the interval timer 10 provided in each requester 80 is different from that of the first embodiment, the configuration of the interval timer 10 will be described.

As shown in FIG. 6A, the interval timer 10 according to the second embodiment receives a use request from the requester 80, and receives the use request when a permission signal from a standby counter 10F described later is high. A use request control unit 10A that transmits a request to the arbitration circuit 90 and transmits a use permission reception signal to the standby counter 10F when the use permission is received from the arbitration circuit 90; And a standby counter value register 10G storing a standby counter value for monitoring the elapse of a standby period until a use request is transmitted, and a standby counter after receiving a use permission received signal as shown in FIG. A standby counter 1 that suspends transmission of the permission signal for a time set by the value and transmits the permission signal to the use request control unit 10A at other times.
0F. Note that the standby counter value can be input by the CPU 30 at any time according to the configuration of the devices connected to the system and the operation status.

Next, as an operation of the second embodiment, FIG.
The operation of the interval timer 10 of each requester 80 and the prioritization of each requester 80 in the entire information processing system 1 will be described with reference to FIG.

Standby counter 1 of interval timer 10
At 0F, the processing shown in FIG. 7 is executed. That is, the standby counter 10F transmits a permission signal to the use request control unit 10A in the normal state (step 132). At this time, upon receiving the use request from the requester 80, the use request control unit 10A immediately transmits the use request to the arbitration circuit 90 because the permission signal at that time is high. Thereby, the arbitration circuit 90 performs arbitration, and the arbitration circuit 90 transmits a use permission to the requester 80 via the use request control unit 10A. Requester 80 that received use permission
Uses a bus based on this use permission and uses a desired resource.

In the second embodiment, the use request control unit 10
When transmitting the use request to the arbitration circuit 90, A simultaneously transmits a use permission received signal to the standby counter 10F. Upon receiving the use permission received signal, the standby counter 10F makes an affirmative determination in step 134 of FIG.
The standby counter value is fetched from the standby counter value register 10G (step 136), and the transmission of the permission signal to the use request control unit 10A is interrupted until the time set by the fetched standby counter value elapses (that is, the permission signal is set to low). ) (Steps 138, 140).

When the use request controller 10A receives a bus use request from the requester 80 during this time period H3 (see FIG. 6B), the permission signal from the standby counter 10F is low, The unit 10A holds the use request without transmitting it to the arbitration circuit 90. That is, the permission signal remains low until the set time based on the standby counter value elapses after the use request control unit 10A transmits one use request to the arbitration circuit 90, so that the use request from the requester 80 is controlled by the use request control. It is held in the unit 10A and is not transmitted to the arbitration circuit 90.

After the elapse of the time set by the standby counter value, an affirmative determination is made in step 140 of FIG.
Then, the process returns to step S32, and the processes after step 132 are executed again.

Thus, the use request control unit 10A sets the requester 80 during the standby period (while the permission signal is low).
Arbitration circuit 9 after the end of the standby period
0. Then, arbitration is performed by the arbitration circuit 90, and the arbitration circuit 90 transmits a use permission to the requester 80 via the use request control unit 10A. The requester 80 that has received the use permission can use a desired resource by using the bus based on the use permission.

As described above, the use request from the requester 80 is controlled so as not to be transmitted to the arbitration circuit 90 during the standby period. Therefore, in the arbitration control system which is hierarchized as shown in FIG. 2, when it is desired to assign the priority order among the requesters A, B, and C as A>B> C, as an example, the arbitration circuit ARB1 requests the bus use right. Signal line (REQ) 12, 1
3 is set so that REQ12 = REQ13, and the arbitration circuit ARB2 sets the priority of REQ21 and REQ23 so that REQ21 = REQ23, and then the standby counter in each of the requesters A, B and C By setting the values so that A <B <C, the priority order among the requesters A, B, and C is A>B> C.
Can be set.

As described above, according to the second embodiment, by setting the standby counter value in the interval timer 10 of each requester 80 in accordance with the priority order to be set, even if the arbitration control system has a plurality of layers, A desired priority can be set for each requester 80. As a result, it is possible for the arbitration circuit 90 to allocate the use permission in a well-balanced manner to the use requests from the plurality of requesters 80 for the bus.

(Third Embodiment) In the third embodiment, FIG.
As shown in (a), since the configuration of the interval timer 10 provided in each requester 80 is different from that of the first embodiment, the configuration of the interval timer 10 will be described.

As shown in FIG. 8A, the interval timer 10 of the third embodiment receives a use request from the requester 80, and when the permission signal from the frequency adjustment unit 10H described later is high, The use request control unit 10A that transmits the use request to the arbitration circuit 90 and an external device (here, as an example, a printer engine (IOT) 71).
Request control unit 10A in synchronization with an external synchronization signal from
And a frequency adjusting unit 10H for transmitting a permission signal.

Next, as an operation of the third embodiment, FIG.
The operation of the interval timer 10 of each requester 80 and the prioritization of each requester 80 in the entire information processing system 1 will be described with reference to FIG.

The frequency adjuster 10 of the interval timer 10
In H, the processing shown in FIG. 9 is executed. That is, when an external synchronization signal from an external device is not received (when the external synchronization signal is low), the frequency adjustment unit 10H transmits a permission signal to the use request control unit 10A (step 162). At this time, upon receiving the use request from the requester 80, the use request control unit 10A immediately transmits the use request to the arbitration circuit 90 because the permission signal at that time is high.
Thereby, the arbitration circuit 90 performs arbitration, and the arbitration circuit 90 transmits a use permission to the requester 80 via the use request control unit 10A. The requester 80 having received the use permission uses a bus and uses a desired resource based on the use permission.

When receiving the external synchronization signal from the external device (when the external synchronization signal becomes high (T1 in FIG. 8B)), the frequency adjustment unit 10H makes an affirmative determination in step 164 and changes the permission signal. Go low (step 166 (FIG. 8)
(T2) of (b)), the permission signal is kept low until the external synchronization signal is no longer received (steps 166 and 16).
8).

In this time zone H4 (see FIG. 8B), when the use request control unit 10A receives a bus use request from the requester 80, the permission signal from the frequency adjustment unit 10H is low. The control unit 10A holds the use request without transmitting it to the arbitration circuit 90. That is, while the external synchronizing signal is received by the frequency adjusting unit 10H, the permission signal remains low, so that the use request from the requester 80 is held by the use request control unit 10A and transmitted to the arbitration circuit 90. There is no.

That is, when a printer is in use and an external synchronization signal from the printer is used, a requester 80 other than the printer is used.
During the reception by the frequency adjustment unit 10H, the use request from the requester 80 other than the printer is controlled not to be transmitted to the arbitration circuit 90, so that the exclusive use of the bus by the printer is ensured.

Then, the printing process in the printer is completed,
When the external synchronization signal is no longer received from the printer (T3 in FIG. 8B), an affirmative determination is made in step 168 in FIG. 9, and the flow returns to step 162 to set the permission signal to high (T4 in FIG. 8B). , The processing after step 162 is executed again.

Thus, the use request control unit 10A transmits the use request received from the requester 80 during reception of the external synchronization signal (while the permission signal is low) to the arbitration circuit 90 after the reception of the external synchronization signal. become. Then, arbitration is performed by the arbitration circuit 90, and the arbitration circuit 90 transmits a use permission to the requester 80 via the use request control unit 10A. The requester 80 that has received the use permission can use a desired resource by using the bus based on the use permission.

As described above, according to the third embodiment, the use request from the requester 80 is controlled so as not to be transmitted to the arbitration circuit 90 while the external synchronization signal is being received. It is possible to avoid such a disadvantage that the processing of the requester that requires the request is obstructed by the use request of the requester whose time is not specified.

In each of the above embodiments, the arbitration circuit 90
Although the example in which the system relating to arbitration includes a plurality of hierarchies is shown, it is needless to say that the present invention can be applied to a system in which arbitration is performed by a single arbitration circuit 90.

The requester 80 in each of the above embodiments (ie, the requester 80 shown in FIGS. 3A, 6A and 8A) is, for example, as shown in FIG. 11A. It may include both a DMA controller and a DMA device. Alternatively, as shown in FIG.
It may indicate only the A device.

In the case where the requester indicates only the DMA device as shown in FIG. 11B, the use request control unit 10A receives the bus use request signal line REQ from the DMA device as the requester 80. DM
A controller 82 and the DMA controller 82
A configuration in which a bus use right permission notification line ACK is received from the device and transmitted to the DMA device.

Even in such a configuration, similarly to the above embodiments, the use request control unit 10A performs an operation of transmitting the received bus use right request signal line REQ to the DMA controller 82 to the DMA device. By controlling the frequency to the set frequency, the bus use right request signal line R
Since the frequency at which the EQ reaches the arbitration circuit 90 can be controlled,
The same effects as in the above embodiments can be obtained.

When the system bus in FIG. 1 is a PCI bus, as shown in FIG. 12, the retry sequence operation is monitored, and when the start of the operation is detected, the invalid state is temporarily invalidated. Use request control unit 10
It is desirable to newly provide an invalidation determination unit 92 for transmitting to A.

That is, when the invalidation judging section 92 detects the start of the retry sequence operation, it transmits an invalidation signal to the use request control section 10A, and receives the invalid signal.
A transmits a use request from the requester 80 to the arbitration circuit 90 regardless of the state of the permission signal. Thereby, regardless of the state of the permission signal, the use request from the requester 80 is immediately transmitted to the arbitration circuit 90, so that it is possible to flexibly and smoothly respond to the retry sequence operation and the like.
There is an advantage.

[0069]

As described above, according to the present invention,
The control unit controls the operation of transmitting the received use request to a frequency set for the requester that transmitted the use request, so that the use request is transmitted at a frequency according to the characteristics of each requester. Therefore, in response to use requests from a plurality of requesters for the shared resource, use permission is allocated in a balanced manner by the arbitration means. In addition, since the above-described control is realized by a control unit different from the arbitration unit, the use permission can be allocated in a well-balanced manner without depending on the configuration or function of the arbitration unit.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of an information processing system according to first to third embodiments.

FIG. 2 is a structural diagram related to arbitration processing in the information processing system of FIG. 1;

FIG. 3A is a configuration diagram of an interval timer according to the first embodiment, and FIG. 3B is a diagram illustrating a state of a permission signal controlled by the interval timer.

FIG. 4 is a flowchart illustrating a process performed by a counter unit according to the first embodiment.

FIG. 5 shows an example of setting a permission period and a non-permission period for each of A, B, and C when the priority order among requesters A, B, and C is A>B> C in the first embodiment. FIG.

FIG. 6A is a configuration diagram of an interval timer according to a second embodiment, and FIG. 6B is a diagram illustrating a state of a permission signal controlled by the interval timer.

FIG. 7 is a flowchart illustrating processing by a standby counter according to the second embodiment.

FIG. 8A is a diagram illustrating a configuration of an interval timer according to a third embodiment, and FIG. 8B is a diagram illustrating a state of a permission signal controlled by the interval timer.

FIG. 9 is a flowchart illustrating a process performed by a frequency adjustment unit according to the third embodiment.

FIG. 10 is a structural diagram related to a conventional arbitration process.

FIG. 11A is a configuration diagram when the requester 80 includes both a DMA controller and a DMA device,
(B) is a configuration diagram in the case where the requester 80 indicates only a DMA device.

FIG. 12 is a configuration diagram of an interval timer provided with an invalidation determination unit.

[Explanation of symbols]

10: interval timer, 10A: use request control unit,
10B ... Counter section, 10F ... Standby counter, 10H ...
Frequency adjustment unit, 80 requester, 90 arbitration circuit, 92
… Invalidation judgment unit

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Sakae Okazaki 3-1-1, Honcho, Iwatsuki-shi, Saitama WATS U Building West Building 4F Inside Fuji Xerox Co., Ltd. (72) Inventor Kei Kei Hatano 3-1-1, Honcho, Iwatsuki-shi, Saitama No. 1 WATS U Building West Building 4F Fuji Xerox Co., Ltd. F-term (reference) 2C061 HJ10 HK11 HK19 5B014 EB03 FB01 FB03 FB04 GA02 GA05 GA13 GA37 5B021 AA01 BB01 BB11 CC04 CC05 DD12 EE01 5B0616 BA01 BB05 BB08

Claims (17)

[Claims] A plurality of requesters for transmitting a use request for a shared resource shared by a plurality of devices; and a plurality of requesters that receive the use request and set at a predetermined frequency for the requester that transmitted the use request. An arbitration control system comprising: a control unit that transmits the received use request; and an arbitration unit that performs arbitration by selecting a requester that permits use of the shared resource according to the received use request. 2. The control means receives the use request and transmits a received use request when a predetermined permission signal is received. The use request control means transmits the permission signal at a predetermined frequency. The arbitration control system according to claim 1, comprising: an adjusting unit. 3. The arbitration control system according to claim 2, wherein a transmission frequency of said permission signal by said frequency adjustment means can be dynamically changed. 4. The arbitration control system according to claim 3, further comprising a period setting unit for setting a permission period for transmitting the permission signal and a non-permission period for not transmitting the permission signal by the frequency adjustment unit. 5. The apparatus according to claim 3, further comprising a standby period setting unit configured to set a standby period from a point in time when one permission signal is transmitted by the frequency adjustment unit until a next permission signal can be transmitted. Arbitration control system. 6. The arbitration control system according to claim 3, wherein said frequency adjusting means controls the transmission operation of said permission signal in synchronization with an external signal. 7. The control device according to claim 1, wherein said control means is provided for each requester and comprises an interval timer capable of adjusting a timing of transmitting a use request. The arbitration control system according to item 1. 8. The control unit further includes a non-permission state invalidating unit that temporarily invalidates a non-permission state in which the permission signal is not transmitted, wherein the non-permission state invalidation unit satisfies a predetermined condition. The arbitration according to claim 2, wherein when the condition is satisfied, an invalidation signal is transmitted, and the use request control unit that receives the invalidation signal transmits a use request regardless of a state of the permission signal. Control system. 9. Arbitration is performed by selecting a plurality of requesters for transmitting a use request for a shared resource shared by a plurality of devices and a requester permitting use of the shared resource according to the received use request. An arbitration control method in an arbitration control system configured to include arbitration means, wherein arbitration control means for controlling arrival of a use request to the arbitration means is provided in the arbitration control system; An arbitration control method comprising: a reception step of receiving the use request; and a transmission step of transmitting the received use request at a predetermined frequency set by the arbitration control unit to the requester that transmitted the use request. . 10. Arbitration is performed by selecting a plurality of requesters that transmit a use request for a shared resource shared by a plurality of devices and a requester that permits use of the shared resource according to the received use request. Arbitration means, provided in an arbitration control system configured to include, receiving the use request, transmitting the received use request at a predetermined frequency set for the requester that transmitted the use request, Arbitration control device characterized by the above-mentioned. 11. A use request control means for receiving the use request and transmitting the received use request when receiving a predetermined permission signal, and a frequency adjusting means for transmitting the permission signal at a predetermined frequency. The arbitration control device according to claim 10, comprising: 12. The arbitration control device according to claim 11, wherein a transmission frequency of said permission signal by said frequency adjustment means can be dynamically changed. 13. The arbitration control device according to claim 12, further comprising a period setting unit for setting a permission period for transmitting the permission signal and a non-permission period for not transmitting the permission signal by the frequency adjustment unit. 14. The apparatus according to claim 12, further comprising a waiting period setting unit for setting a waiting period from a point in time when one permission signal is transmitted by said frequency adjusting unit until a next permission signal can be transmitted. Arbitration control device. 15. The arbitration control device according to claim 12, wherein the frequency adjustment unit controls the transmission operation of the permission signal in synchronization with an external signal. 16. The arbitration control according to claim 10, wherein the arbitration control is provided with an interval timer provided for each requester and capable of adjusting a timing of transmitting a use request. apparatus. 17. A non-permitted state invalidating means for temporarily invalidating a non-permitted state in which the permission signal is not transmitted, wherein the non-permitted state invalidating means invalidates when a predetermined condition is satisfied. The arbitration control device according to claim 11, wherein the use request control unit that has transmitted the invalidation signal and has received the invalidation signal transmits a use request regardless of the state of the permission signal.