Dynamically scaling voltage/frequency
View Patent ↗Disclosed are various embodiments providing processing circuitry that generates an output for each clock cycle of a clock signal using a logic block, the logic block being powered by a supply voltage. The processing circuitry detects whether the output has stabilized at a point in time before the end of a clock cycle of the clock signal, the point in time being based at least upon a delay line. In response to detecting whether the output has stabilized at a point in time, the processing circuitry dynamically adjusts at least one of the supply voltage or the frequency of the clock signal.
1. A system comprising:
a logic block configured to generate an output on a per clock cycle basis;
a register connected to the output of the logic block and configured to receive the output from the logic block and to generate a written output, the register comprising
a detection circuit configured to sample the output directly from the logic block according to a global clock to generate a sampled output, and
a service circuit to sample the output directly from the logic block according to a delayed global clock to generate the written output; and
a comparator circuit including a single logic gate configured to receive the written output and the sampled output and configured to generate a warning signal when the written output does not match the sampled output,
wherein the detection circuit comprises a latch, and the latch is transparent during an inactive portion of the global clock, and
wherein the service circuit comprises a flip-flop.
2. The system of claim 1 , further comprising a delay line for generating the delayed global clock based at least upon the global clock.
3. The system of claim 2 , further comprising stabilization circuitry configured to stabilize the warning signal based at least upon on combining the global clock and the delayed global clock.
4. The system of claim 3 , wherein combining comprises generating a stabilization clock signal by performing an AND operation on the global clock and the delayed global clock.
5. The system of claim 1 , wherein the single logic gate comprises an XOR gate.
6. The system of claim 1 , further comprising:
a dynamic voltage frequency controller configured to adjust at least one of a frequency of the global clock or a power supply voltage based on the warning signal.
7. The system of claim 1 , wherein the detection circuit includes an inverter to synchronize sampling of the output to a compliment of the global clock.
8. A method comprising:
generating an output from a logic block on a per clock cycle basis;
receiving the output of the logic block at a register;
sampling, by a detection circuit of the register, the output directly from the logic block according to a global clock to generate a sampled output;
sampling, by a service circuit of the register, the output directly from the logic block according to a delayed global clock to generate a written output;
comparing, in a comparator that includes a single logic gate, the written output and the sampled output; and
generating, by the comparator, a warning signal when the written output does not match the sampled output,
wherein the detection circuit of the register comprises a latch, and the latch is transparent during an inactive portion of the global clock, and
wherein the service circuit of the register comprises a flip-flop.
9. The method of claim 8 , further comprising delaying, with a delay line, the global clock to generate the delayed global clock.
10. The method of claim 9 , further comprising stabilizing the warning signal, with a stabilization circuit, based at least upon a combination of the global clock and the delayed global clock.
11. The method of claim 10 , further comprising generating the combination of the global clock and the delayed global clock through an AND operation.
12. The method according to claim 8 , wherein the single logic gate is an XOR gate, and the comparing is performed by performing an XOR operation on the written output and the sampled output.