JPH08171523A - Synchronization control method of communication control system - Google Patents

Abstract

PURPOSE: To provide the synchronization control method of the communication control system which shorten a synchronization control time that is not necessary for an original communication control processing and improves the processing speed of a CCU. CONSTITUTION: A CPU 1 when setting command descriptors adds discrimination information on communication processing instruction to the individual command descriptors and previously informs the CPU of the number of set command descriptors or whether or not there is a command descriptor and the CCU 2 when setting status descriptors adds discrimination information on processing result reports to the individual status descriptions and previously informs the CPU 1 of the number of set status descriptors or whether or not there is a status descriptor. Thus, the CCU 2 and CPU 1 need not to recognize whether or not the individual descriptors and their availability by accessing a main memory 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to an information processing device (hereinafter,
The present invention relates to a communication control system that uses a descriptor that sets a processing instruction and a processing result report performed between a CPU and a communication control unit (hereinafter, CCU) in a main memory, and particularly, system synchronization between the CPU and the CCU. Regarding control method. Note that the CCU includes a communication control processing device having a processor inside.

[0002]

2. Description of the Related Art In a communication control system in which a large number of CCUs are connected to a common bus or which includes CCUs capable of high-speed communication, processing such as descriptor replacement is reduced as much as possible to reduce the processing speed of individual CCUs. It is important to prevent the decline. Then, the "descriptor chaining method" disclosed in Japanese Patent Application No. 02-190062.
Then, by connecting the descriptors in a ring shape and making them logically continuous, the time required for the descriptor replacement processing described above is eliminated, and a decrease in the processing speed of the CCU is prevented.

In this "descriptor chaining method", however, since descriptors are connected in a ring shape and set, the contents of the communication processing instruction and the processing result report set in the descriptor setting area change over time. . Therefore, when the CPU and the CCU operate asynchronously, it is inevitable to perform synchronous control regarding the transfer of descriptors that are not necessary for the original communication processing.

A conventional synchronization control method of this type will be described below with reference to FIGS. FIG. 6 is a block diagram of a communication control system, which is configured by connecting a CPU 4, a CCU 5, and a main memory 6 via a bus so that bidirectional communication is possible. The CPU 4 includes a main controller 41 and an interface controller 42, and has a CCU 5
It is possible to activate an input / output command for and to attach data at that time. The CCU 5 includes a main control unit 51, an interface control unit 52, and a communication processing unit 53,
The CPU 4 can be activated by an interrupt and data can be attached at that time. Also, in the main memory 6,
The command table 61 and the status table 62 are
It is set to be accessible from the CPU 4 and the CCU 5, respectively. The CCU 4 also has initial setting means. The initial setting means sets the address and size of the command table 61 and the address and size of the status table 62, respectively.

FIG. 7A is an explanatory diagram of the command table 61, and FIG. 7B is an explanatory diagram of the status table 62.
The communication processing instruction from the CPU 4 to the CCU 5 is stored in each command descriptor 611. The command table 61 is a storage area of the command descriptor 611 that is continuously secured in the main memory 6, and here, an instruction from the line connection to the start data transmission, the main data transmission, the end data transmission, and the line disconnection (operation code ) 612,
The address 613 of the data buffer 63, the buffer size 614, and the valid flag 615 that are secured as necessary.
8 shows an example in which eight command descriptors 611 including "" are secured. Here, the valid flag 615 is the operation code 61 set in the command descriptor 611.
A flag indicating that information including 2 is valid, and C
It is set by PU4 and reset by CCU5. In this command table 61,
The individual command descriptors 611 are chained on the ring in a circular (round robin) form, and the eighth command descriptor and the first command descriptor are linked.

The result of the CCU 5 performing the processing in accordance with the communication processing instruction from the CPU 4 is the status descriptor 62.
It is stored in 1. The status table 62 is a status descriptor 6 that is continuously secured in the main memory 6.
21 in the storage area, here, the processing result report (result code) 6 corresponding to the command descriptor 611.
22 shows an example in which eight status descriptors 621 including the address 623 of the buffer 63, the size 624, and the valid flag 625, which are secured as necessary, are secured. Here, the valid flag 625 is a flag indicating that the information including the result code 622 set in the status descriptor 621 is valid, and the CCU
5 is set and the CPU 4 is reset. Also in this status table 62, individual status descriptors 621 are chained in a ring in a circular form, and the eighth status descriptor and the first status descriptor are linked.

FIG. 8 is a flow chart showing a synchronous control procedure when the CPU 4 and the CCU 5 exchange the command descriptor 611 and the status descriptor 621 via the main memory 6. Hereinafter, this sequence will be described with reference to FIG.

First, the CPU 4 stores the operation code 612, the buffer address 613, and the buffer size 6 in the main memory 6 according to the format of the command descriptor 611.
14 and the valid flag 615 are set (S201), and the setting contents are notified to the CCU 5 by an input / output command (S20).
2).

When the CCU 5 receives the setting notification (S203), it reads the command descriptor 611 from the main memory 6 (S204) and performs a predetermined communication process based on it (S205). When processing is completed (S
206), and reset the valid flag 615 of the command descriptor 611 (S207). The CCU 5 also reads out the valid flag 625 to confirm that the status descriptor 621 can be overwritten and confirms that the valid flag 625 has been reset (S208).
Then, the processing result report is sent to the status descriptor 621.
Valid flag 625, result code 62 according to the format of
2, buffer address 623, and buffer size 62
4 is set (S209). Furthermore, the command table 6
1 is read, and it is confirmed by the valid flag 615 whether or not there is a command descriptor 611 that continues (S21).
0). After that, the status descriptor 6 is sent to the CPU 4.
The setting contents of 21 are notified by interruption (S211).

When the CPU 4 receives the setting notification from the CCU 5 (S212), the status descriptor 6
21 is read (S213), and when the processing based on the status descriptor 621 is completed (S214, S
215), and reset the valid flag 625 (S2).
16).

[0011]

In the above sequence, the CCU 5 reads the command descriptor 6 read by the CCU 5.
The valid flag 615 of 11 is reset (S207), the preceding status descriptor 621 is read and the valid flag 625 is checked (S208), and the continuous command descriptor 611 is read and the valid flag is checked (S210) each time. Because it doesn't
There is a problem that a great amount of time is spent for the above-mentioned processing which is unnecessary for the original communication control processing, and the communication control speed is reduced.

An object of the present invention is to solve the above-mentioned problems and shorten the synchronization control time unnecessary for the original communication control processing to reduce CC.
It is to provide a synchronous control method for a communication control system that improves the processing speed of U.

[0013]

According to a first method provided by the present invention, a communication processing instruction from a CPU to a CCU is issued via a command descriptor, and the CCU which reads out the command descriptor performs individual communication processing. A synchronous control method for a communication control system that reports a processing result based on an instruction via a status descriptor, wherein each command descriptor is set when the CPU sets a command descriptor when the command descriptor is set by the CPU. In addition to the identification information of the communication processing instruction, the number of set command descriptors is notified to the CCU in advance, and when the CCU sets the status descriptor, the identification information of the processing result report is added to each status descriptor. And set the stay And notifying in advance the information processing apparatus the number of scan descriptors. The CPU
May notify the CCU of the number of status descriptors for which the processing based on the processing result report has been completed, together with the number of command descriptors.

The second method provided by the present invention is C
When the PU sets the command descriptor, the CCU is notified in advance of the presence or absence of the set command descriptor, and the identification information of the communication processing instruction and the display of the continuous communication processing instruction are added to each command descriptor. When the CCU sets the status descriptor, the identification information of the processing result report and the display of the continuous processing result report are added to each status descriptor. The CPU determines the number of status descriptors for which the processing based on the processing result report has been completed, together with the presence or absence of the command descriptor, and the C
The CU may be notified.

[0015]

Next, an embodiment of the present invention will be described in detail with reference to the drawings. (First Embodiment) FIG. 1 is a block diagram of a communication control system according to the first embodiment, which includes a CPU 1, a CCU 2, and a main memory 3.
It is composed by connecting and by a bus.

In addition to the functions of the conventional CPU 4, the CPU 1 adds the identification information of the communication processing instruction, such as a command number, to each command descriptor when setting the command descriptor in the main memory 3 and sets the command descriptor. A descriptor management unit 12 for managing the number is further provided, and further, the main control unit 11 notifies the CCU2 of the set number of descriptors in advance by an input / output command, and the processing based on the processing result report from the CCU2 is completed. It has a function of notifying the CCU 2 of the number of status descriptors together with the number of command descriptors.

In addition to the function of the conventional CCU 5, the CCU 2 also sets the status descriptor in the main memory 3 when identifying the status descriptor, such as the identification information of the processing result report, for example, the command number added to the command descriptor. Further, the main control unit 21 has a function of interrupting the CPU to notify the CPU of the set number of status descriptors in advance. A command table 31 and a status table 32 are stored in the main memory 3 as in the conventional device.

FIG. 2A is an explanatory diagram of the command table 31, and FIG. 2B is an explanatory diagram of the status table 32. In the illustrated example, in the command table 31, the command number 312, an instruction (operation code) 313 from line connection to start data transmission, main data transmission, end data transmission, line disconnection, and a data buffer secured as necessary Three
8 shows an example in which eight command descriptors 311 including an address 314 of 3 and a buffer size 315 are secured.

The individual command descriptors 311 are chained on the ring in a circular form, and the eighth command descriptor and the first command descriptor are linked. In the status table 32, the command number 322 corresponding to the above command number 312,
The status descriptor 321 including the processing result report (result code) 323, the address 324 of the buffer 33 secured as necessary, and the buffer size 325 is 8
An example is shown in which the number is secured. Also in this status table 32, individual status descriptors 321 are chained on the ring in a circular form, and the eighth status descriptor and the first status descriptor are linked. The command numbers 312 and 322 for identifying the command descriptor and the status descriptor can be set to arbitrary values as long as they are exclusive between the descriptors. For example, the serial number of the descriptor and the storage address of the descriptor in the table can be set.

In FIG. 3, CPU 1 and CCU 2 are main memories 3
9 is a flowchart showing a synchronous control procedure when a command descriptor 311 and a status descriptor 321 are exchanged via the. Hereinafter, this sequence will be described with reference to FIG.

First, the CPU 1 sets a command number 312, an operation code 313, a necessary buffer address 314 and a buffer size 315 in the main memory 3 according to the format of the command descriptor 311 (S101) and newly sets them. The CCU 2 is notified of the number of command descriptors (hereinafter, LCWC) by the input / output command (S102).

When receiving the LCWC (S103), the CCU 2 manages the L managed by the descriptor management unit 22.
The CWC is updated (S104), the command descriptor 311 is read from the main memory 3 (S105),
A predetermined communication process based on it is performed (S106). When the processing is completed, the command number 322 and the result code 32 are output according to the format of the status descriptor 321.
3, and the required buffer address 623 and buffer size 624 are set (S107). At this time, it is checked whether or not there is an empty area in the status table 32 (S10
8) If there is an empty area, the descriptor management unit 22
It is determined whether the LCWC in the table is "1" or more (S10
9) If "1" or more, subtract "1" (S11
0), the processes from S105 onward are repeated, and the number of status descriptors 321 set in the status table 32 is interrupted and notified to the CPU 1 as a newly set number of status descriptors (hereinafter, INTC) (S111). If the status table 32 is full or the LCWC is less than "1", the CPU1
Wait for the LCWC to be notified by the I / O command from.

When receiving the INTC (S112), the CPU 1 reads the newly set status descriptor 321 from the status table 32 (S112).
113), when the processing based on the status descriptor 321 is completed (S114, S115), the number of status descriptors (hereinafter, LSWC) for which the processing is completed is notified to the CCU 2 by an input / output command (S11).
6). The CCU 2 is the LS in the descriptor management unit 22.
The WC is updated (S117).

When it is necessary to set a new command descriptor 311 by the processing based on the status descriptor 321 (S114), the CPU 1 sets the command descriptor 311 (S11).
101), LCWC and LSWC can be notified to CCU2 collectively. In this case, the CCU 2 updates the LCWC and LSWC managed by the descriptor management unit 22 at the same time. LCWC and LSWC are independent values, LCWC is zero / non-zero, LSWC is zero /
All non-zero combinations are possible. LCWC and L
The input / output instruction when both SWC are zero has no meaning.

(Second Embodiment) Next, a second embodiment of the present invention will be described with reference to FIGS. FIG. 4A is an explanatory diagram of a command descriptor according to the second embodiment, and FIG. 4B is an explanatory diagram of a status descriptor.

In this embodiment, the continuation flags 316 and 326 are respectively added to the command descriptor 311 and status descriptor 321 that are exchanged in the first embodiment.
Is additionally set. The continuation flag 316 set in the command descriptor 311 indicates the presence / absence of the next command descriptor that continues, and the continuation flag 326 set in the status descriptor 321 indicates the presence / absence of the next status descriptor that continues. is there. Accordingly, in the first embodiment, the CPU 1 to C
In place of the LCWC and LSWC notified to the CU2 by the input / output command, the presence or absence of the command descriptor setting (hereinafter: L
CWE) and LSWC are used. LCWE and LSWC are independent values, and LCWE is zero / non-zero,
All combinations of zero and non-zero LSWC are possible. The input / output instruction when LCWE and LSWC are both zero has no meaning.

In the first embodiment, CCU2
Notifies the CPU 1 of the number of status descriptors set in the status table 32 by an interrupt, but in this embodiment, the status descriptor 321 is notified by a continuation flag 326 indicating the presence or absence of the next status descriptor. Therefore, as in the first embodiment, I
There is no need to notify the NTC by interruption.

FIG. 5 is a block diagram of the communication control system according to the second embodiment. In the main memory 3, a command table 34 in which a command descriptor having the contents shown in FIG. The status table 35 in which the status descriptor having the contents of b) is secured is set. The synchronization control procedure in the communication control system having such a configuration is the same as the LCWC or INT in the processing procedure of FIG.
The process related to C can be omitted, and the time for transmitting / receiving the descriptor can be further shortened.

Thus, comparing with the conventional synchronous control procedure of FIG. 8, according to the first and second embodiments, the CP
The following processing in U1 and CCU2 becomes unnecessary. (1) Reset processing of the valid flag of the command descriptor (S207). According to each of the above-described embodiments, the execution management of the command descriptor 311 can be performed by the command number 312/322 for identifying the descriptor. Therefore, a valid flag is set for each communication process execution based on each command descriptor as in the conventional case. No need to reset. This can shorten the time considerably when the number of descriptors is large, and can be a more effective method. (2) Read / confirm process of valid flag of preceding status descriptor (S208) and read / confirm process of setting area of continuing command descriptor (S21)
0). The CCU 2 can immediately recognize the presence or absence of an empty area in the status table 32 by the LCWC or LSWC notified by the input / output instruction from the CPU 1, and can also recognize the presence of the next command descriptor by the continuation flag 316. Can be moved to. (3) Reset processing of the valid flag of the status descriptor (S216). The CPU 1 uses the INTC or the status descriptor 321 notified by an interrupt from the CCU.
Since the result of the predetermined communication process can be grasped by the continuation flag 326 set to, it is possible to shift to the next process.

[0030]

As is apparent from the above description, in the synchronous control method of the communication control system of the present invention, when the CPU sets the command descriptor, the identification information of the communication processing instruction is added to each command descriptor. In addition, the CCU is notified in advance of the number of command descriptors set or the presence or absence of command descriptors, and when the CCU sets the status descriptor, the identification information of the processing result report is added to each status descriptor, and the set status is set. Since the CPU is notified in advance of the number of descriptors or the presence / absence of status descriptors, the CCU and the CPU immediately access the main memory to check the presence / absence of individual descriptors or their validity without delay for the original communication control. Processing becomes executable Is effective, conventional problems can be solved.

In particular, in the configuration in which the CPU notifies the CCU of the number of status descriptors in which the processing based on the processing result report has been completed, together with the number of command descriptors, there is an effect that the time required for synchronous control is further shortened.

[Brief description of drawings]

FIG. 1 is a configuration diagram of main parts of a communication control system according to a first embodiment of the present invention.

2A is an explanatory diagram of a command table used in the first embodiment, and FIG. 2B is an explanatory diagram of a status table.

FIG. 3 is a synchronization control procedure diagram when the CPU and the CCU exchange a command descriptor and a status descriptor via the main memory according to the first embodiment.

4A is an explanatory diagram of a command descriptor according to a second embodiment of the present invention, and FIG. 4B is an explanatory diagram of a status descriptor.

FIG. 5 is a configuration diagram of a main part of a communication control system according to a second embodiment, in which a command table in which a command descriptor having the content of FIG.
The example in which the status table which secured the status descriptor of the content of (b) was set is shown.

FIG. 6 is a configuration diagram of a main part of a conventional communication control system.

FIG. 7A is an explanatory diagram of a conventional command table,
(B) is an explanatory diagram of a status table.

FIG. 8 is a synchronous control procedure diagram when a conventional CPU and CCU exchange a command descriptor and a status descriptor via a main memory.

[Explanation of Codes] 1,4 CPU 2,5 CCU 3,6 Main memory 11,41 CPU main control unit 21,51 CCU main control unit 12 CPU descriptor management unit 22 CCU descriptor management unit 31,61 Command Table 311,611 Command Descriptor 32,62 Status Table 321,621 Status Descriptor 312,322 Command Number 316,326 Continuation Flag

Claims (4)

[Claims] 1. A communication processing instruction from an information processing apparatus to a communication control apparatus is issued via a command descriptor, and the communication control apparatus that has read the command descriptor issues a processing result report based on each communication processing instruction via a status descriptor. In the synchronization control method of the communication control system to be performed by, the information processing device, when setting the command descriptor, while adding the identification information of the communication processing instruction to each command descriptor, the number of command descriptors set in advance Notifying the communication control device, when the communication control device sets the status descriptor, the identification information of the processing result report is added to each status descriptor, and the number of set status descriptors is notified to the information processing device in advance. It is characterized by Synchronization control method of the control system. 2. The communication control system according to claim 1, wherein the information processing apparatus notifies the communication control apparatus of the number of status descriptors for which the processing based on the processing result report has been completed, together with the number of command descriptors. Synchronous control method. 3. A communication processing instruction from an information processing apparatus to a communication control apparatus is issued via a command descriptor, and the communication control apparatus which has read the command descriptor issues a processing result report based on each communication processing instruction via a status descriptor. A method for synchronizing control of a communication control system, wherein when the information processing device sets a command descriptor, the communication control device is notified in advance of the presence or absence of a command descriptor that has been set, and the communication processing is performed on each command descriptor. Addition of identification information of the instruction and display of the continuous communication processing instruction, and when the communication control device sets the status descriptor, the identification information of the processing result report and the display of the continuous processing result report in each status descriptor, and Communication control system characterized by adding Synchronization control method systems out. 4. The communication control system according to claim 3, wherein the information processing apparatus notifies the communication control apparatus of the number of status descriptors for which the processing based on the processing result report is completed, together with the presence or absence of the command descriptor. Synchronization control method.