Methods of indirect register access including automatic modification of a directly accessible address register
Systems and methods are provided for managing access to registers. A system may include a set of direct registers and a set of indirect registers. The indirect registers may be accessed through the direct registers, and the direct registers may provide various features to provide faster access to the indirect registers. One of the direct registers may indicate access modes for accessing the indirect registers. The access modes may include auto-increment, auto-decrement, auto-reset, and no change modes. Based on the access mode, the currently accessed address may be automatically modified after accessing the indirect register at the address.
1. A method of accessing registers, comprising:
directly accessing a first set of registers;
indirectly accessing a second set of registers via the first set of registers; and
selecting one of a plurality of auto-change modes based on a first register of the first set of registers, wherein accessing the first register of the first set of registers sets a second register of the first set of registers to a predetermined value, wherein the plurality of auto-change modes comprises:
an auto-increment mode in which a first address stored in the second register of the first set of registers is incremented at the completion of a bus cycle;
an auto-decrement mode in which a first address stored in the second register of the first set of registers is decremented at the completion of the bus cycle; and
an auto-reset mode in which the second register is set to a predetermined value at the completion of the bus cycle.
2. The method of claim 1 , wherein accessing the second set of registers comprises accessing a third register in the second set of registers via a first address stored in the second register of the first set of registers.
3. The method of claim 2 , comprising incrementing a first address to access a fourth register.
4. The method of claim 2 , comprising decrementing a first address to access a fourth register.
5. The method of claim 2 , comprising automatically modifying a value stored in the second register in accordance with a logical function.
6. The method of claim 5 , wherein the logical function includes at least one of an OR function, an AND function, or an XOR function.
7. A method comprising:
directly accessing a first set of registers;
indirectly accessing a second set of registers via the first set of registers, wherein accessing the second set of registers comprises accessing a second register via a first address stored in an address register of the first set of registers; and
automatically modifying the value stored in the address register in accordance with a hash function.
8. A method of processing data, comprising:
executing a first cycle, comprising:
writing a bank address to a first register of a first set of registers;
setting a register address of a second register of the first set of registers;
accessing a third register of a second set of registers indicated by the bank address and the register address; and
reading an auto-change mode from the first register; and
executing a second cycle, comprising:
automatically modifying the register address of the second register in accordance with the auto-change mode read from the first register;
wherein setting the register address of the second register includes setting the register address to a predetermined value; and
wherein setting the register address to the predetermined value is automatically performed in response to writing the bank address to the first register.
9. The method of claim 8 , wherein setting the register address includes writing the register address to the second register.
10. The method of claim 8 , comprising executing a third cycle, comprising accessing a fourth register of the second set of registers indicated by the bank address and the automatically modified register address.
11. The method of claim 8 , wherein automatically modifying the register address includes incrementing the register address.
12. The method of claim 8 , wherein automatically modifying the register address includes decrementing the register address.
13. The method of claim 8 , wherein accessing the third register includes reading data stored in the third register.
14. The method of claim 8 , wherein accessing the third register includes writing data from an additional register of the first set of registers to the third register.