Error processing method and information processing apparatus
View Patent ↗An error processing method processes an error generated on a bus of a CPU, by inputting a bus error that is generated on at least one of an instruction bus and a data bus of the CPU to the CPU by a bus error input part, counting the bus error by a bus error counter part of the CPU, and specifying a region of a memory part that is coupled to the CPU based on a value of the bus error counter part.
1. An error processing method for processing an error generated on a bus of a CPU, comprising:
writing a plurality of identical instructions or data respectively to a plurality of pages of a memory part that is coupled to the CPU;
inputting a bus error that is generated on at least one of an instruction bus and a data bus of the CPU to the CPU by a bus error input part;
counting the bus error by a bus error counter part of the CPU; and
specifying one of the plurality of pages of the memory part based on a value counted by the bus error counter part, an address of one of the plurality of identical instructions or data, and a read signal, in order to read one of the plurality of identical instructions or data from the one of the plurality of pages that is specified.
2. The error processing method as claimed in claim 1 , comprising:
updating the value of the bus error counter part when the bus error is generated, if the bus error is generated on the instruction bus and a judgment is made to jump to an exception vector of an undefined instruction or, if the bus error is generated on the data bus.
3. The error processing method as claimed in claim 1 , comprising:
updating the value of the bus error counter part when the bus error is generated, if the bus error is generated on the data bus.
4. The error processing method as claimed in claim 1 , comprising:
carrying out a process of an undefined instruction when the bus error is generated on the instruction bus after confirming that no bus error is generated for an immediately preceding instruction.
5. The error processing method as claimed in claim 1 , comprising:
carrying out a process of an undefined instruction when the bus error is generated on the data bus by prohibiting setting of a general-purpose register part by a subsequent instruction.
6. The error processing method as claimed in claim 1 , comprising:
inputting an error signal to the bus error input part when a parity error is generated in the memory part when an instruction is fetched,
wherein the CPU carries out an Exception, Interrupt, Trap (EIT) process and jumps to a routine of an error process at a time when the CPU judges to execute an instruction for which the error is generated.
7. The error processing method as claimed in claim 1 , comprising:
cancelling processes of subsequent instructions when a parity error is generated on the data bus and an error signal is input to the CPU by the bus error input part.
8. The error processing method as claimed in claim 1 , comprising:
indicating a generation of the bus error by storing an instruction bus error and a data bus error in a processor status register that indicates a state of the CPU.
9. The error processing method as claimed in claim 1 , comprising:
carrying out a retry when an instruction bus error or a data bus error is generated, and carrying out a bus error process if a bus error is generated even after the retry.
10. An information processing apparatus comprising:
a CPU;
a memory part coupled to the CPU and including a plurality of pages configured to be respectively written with a plurality of identical instructions or data;
a bus error input part configured to input, to the CPU, a bus error that is generated on at least one of an instruction bus and a data bus of the CPU;
a bus error counter part configured to count the bus error that is generated within the CPU; and
a specifying part configured to specify a region of the memory part based on a value counted by the bus error counter part,
wherein said specifying part specifies one of the plurality of pages of the memory part based on the value counted by the bus error counter part, an address of one of the plurality of identical instructions or data, and a read signal, in order to read one of the plurality of identical instructions or data from the one of the plurality of pages that is specified.
11. The information processing apparatus as claimed in claim 10 , comprising:
an updating part configured to update the value of the bus error counter part when the bus error is generated, if the bus error is generated on the instruction bus and a judgment is made to jump to an exception vector of an undefined instruction or, if the bus error is generated on the data bus.
12. The information processing apparatus as claimed in claim 10 , comprising:
an updating part configured to update the value of the bus error counter part when the bus error is generated, if the bus error is generated on the data bus.
13. The information processing apparatus as claimed in claim 10 , comprising:
a part configured to carry out a process of an undefined instruction when the bus error is generated on the instruction bus after confirming that no bus error is generated for an immediately preceding instruction.
14. The information processing apparatus as claimed in claim 10 , comprising:
a general-purpose register part including the bus error counter part; and
a part configured to carrying out a process of an undefined instruction when the bus error is generated on the data bus by prohibiting setting of the general-purpose register part by a subsequent instruction.
15. The information processing apparatus as claimed in claim 10 , comprising:
a part configured to input an error signal to the bus error input part when a parity error is generated in the memory part when an instruction is fetched,
wherein the CPU carries out an Exception, Interrupt, Trap (EIT) process and jumps to a routine of an error process at a time when the CPU judges to execute an instruction for which the error is generated.
16. The information processing apparatus as claimed in claim 10 , comprising:
a part configured to cancel processes of subsequent instructions when a parity error is generated on the data bus and an error signal is input to the CPU by the bus error input part.
17. The information processing apparatus as claimed in claim 10 , comprising:
a processor status register configured to indicate a state of the CPU,
wherein a generation of the bus error is indicated by storing an instruction bus error and a data bus error in the processor status.
18. The information processing apparatus as claimed in claim 10 , comprising:
a part configured to carry out a retry when an instruction bus error or a data bus error is generated, and to carry out a bus error process if a bus error is generated even after the retry.