JPH04260147A - Diagnostic system for local memory - Google Patents

Abstract

PURPOSE:To prevent the unanswerability to a communication from other processor of each processor by executing only a part of a diagnostic test of a local memory in the biginning, and executing separately the remaining part. CONSTITUTION:To a first processor having a local memory 2, a second processor (both are not shown in the figure) having a local memory of a different capacity is added. In this case, a diagnostic test of the local memory 2 is executed only a part thereof, and the remaining part is executed separately. In this case, a capacity value of the local memory 2 for executing an initial diagnosis is put in a register 9. A counter 7 executes counting, whenever write or readout to one address of the local memory 2 is finished. A comparator 10 compares the contents of the register and the contents of said counter. In such a way, when the comparator 10 detects the coincidence, the initial diagnostic test of the local memory 2 is suspended, and after a mutual diagnosis between the processors is finished, the remaining diagnostic test is executed.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for diagnosing a local memory of a processor.

0002

2. Description of the Related Art Conventionally, in an information processing apparatus having a plurality of processors having local memories of different capacities, mutual diagnosis is performed by communication between the processors after all diagnostic tests of the local memories have been completed.

0003

[Problems to be Solved by the Invention] In the above-mentioned method, since the capacity of local memory differs depending on each processor, the diagnostic test time of the local memory with the largest capacity is taken as a reference, and mutual diagnosis between processors is performed after that time has elapsed. was running a test. Therefore, when connecting a new processor with a larger capacity local memory than before, the mutual diagnostic test will start before the diagnosis of that local memory has finished, and that processor will be The disadvantage is that communications cannot be answered within a specified time, and errors are detected in mutual diagnostic tests.

0004

[Means for Solving the Problems] The local memory diagnostic method of the present invention performs a local memory diagnostic test when a second processor having a local memory of a different capacity is added to a first processor having a local memory. It is configured so that only a part of it is executed initially, and the remaining part is executed separately.

Furthermore, the local memory diagnostic method of the present invention includes a register that stores the capacity value of the local memory for which initial diagnosis is performed, and a counter that counts each time writing to or reading from one address of the local memory is completed. and a comparator for comparing the contents of the register and the contents of the counter, and when the comparator detects a match, the initial diagnostic test of the local memory is interrupted, and after the mutual diagnosis between the processors is completed, the remaining local The memory is configured to perform diagnostic tests.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be explained with reference to the drawings.

FIG. 1 is a block diagram of one embodiment of the present invention. In the figure, an instruction execution unit 1 outputs an address to a local memory 2 and a cache 3 via an address path 4. At this time, the request is issued to either the local memory 2 or the cache 3. If it is a read request, data is transferred from either the local memory 2 or the cache 3 to the instruction execution unit 1 via the data path 5. Further, in the case of a write request, data is transferred from the instruction execution unit 1 to the local memory 2 or cache 3. Also, cache 3
has an interface with the main memory 6 and stores part of the data in the main memory 6.

FIG. 2 is a block diagram showing a part of the instruction execution section 1 mentioned above. In the same figure, the counter 7 is
The count is incremented when reading from, reading from, or writing to local memory is completed according to an instruction from the local memory. Further, the register 9 stores the upper limit address for performing an initial diagnostic test of the local memory.

[0009] At the time of a local memory diagnostic test, first,
Write the maximum address in the register 9, set the start address for starting the diagnostic test in the counter 7, write data to the local memory from that start address,
The counter counts up along with the address. The value of the counter 7 and the value of the register 9 are compared each time by a comparator 10, and data is written to the local memory until they become the same value.

Next, as in the case of writing, the upper limit address is written to the register 9, a start address is set to the counter 7, and data is read from the local memory from the start address. The counter 7 counts up together with the address every time it is read. The value of the counter 7 and the value of the register 9 are compared each time by a comparator 10, and data is read from the local memory until they become the same value. At this time, each address is checked to see if the written data matches the read data. If they do not match, it is determined as an error and the diagnostic test is interrupted. In this way, a diagnostic test is first performed on the local memory of all processors for a certain capacity.

Next, mutual diagnosis between a plurality of processors is performed. In mutual diagnosis, one processor A issues a communication to another processor B, and processor B, which receives the communication, stores data indicating the reception in a predetermined area of the main memory. Thereafter, a communication is issued to processor A as the communication destination. Processor A monitors the time to see if communication is received from processor B within a predetermined time, and determines an error if no communication is received within the predetermined time. Further, when a communication from processor B is received, a predetermined area of the main memory is checked to confirm that processor B has received communication from processor A.

[0012] When each processor finishes mutual diagnosis, if there is any part of the local memory that has not been tested yet,
Perform diagnostic tests on that part.

[0013]

As explained above, the present invention divides and performs a local memory diagnostic test, so that in a mutual diagnostic test between processors, since each processor is undergoing a local memory diagnostic test, other processors This can prevent errors caused by not being able to respond to communications from. This effect is particularly significant when a processor with a local memory larger in capacity than before is added later.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing one embodiment of the present invention.

FIG. 2 is a block diagram showing part of an instruction execution unit.

[Explanation of symbols]

1 Instruction execution unit 2. Local memory ３　　　　Cache 6 Main memory 7 Counter 8 Control section 9 Register 10 Comparator

Claims (2)

[Claims] [Claim 1] When a second processor having a different capacity of local memory is added to a first processor having a local memory, only a portion of the local memory diagnostic test is initially executed, and the remaining portion is executed separately. A local memory diagnostic method characterized by: 2. A register that stores a capacity value of a local memory for performing initial diagnosis, a counter that counts each time writing or reading to one address of the local memory is completed, and a register that stores the contents of the register and the contents of the counter. and a comparator for comparison, and when the comparator detects a match, the initial diagnostic test of the local memory is interrupted, and after the mutual diagnosis between the processors is completed, the diagnostic test of the remaining local memory is executed. 2. The local memory diagnostic method according to claim 1.