Does GPC/TPC support Power Gating Switch in the GPU?

Robotics & Edge Computing Jetson Systems Jetson Thor
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Hi, we conducted some experiments to disable some GPC/TPC to reduce power consumption.

However, based on our test data, disabling GPC/TPC has little impact on power consumption.

Could you please help confirm if there is a GPC/TPC power gating switch in Thor’s GPU?

Thank you.

GPU GPU_PG_MASK GPU freq temperature 81 (mW) temperature 41 (mW)
1GPC（14CPU） 16257（0b11 1111 1000 0001） 54M 3636 2328
3GPC（14CPU） 1 (0b00 0000 0000 0001) 54M 3804 2556
Diff 168 228
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Yes, GPC/TPC power gating is supported. However, the actual power number difference may not be large because:

  • There are other GPU low power features suppressing the power
  • The GPU rail voltage is low

The power difference should be more obvious when running a GPU workload.

To easily confirm whether the power gating is applied, use tegrastats to check which GPC clocks are active. For example:

  • When only 1 GPC is active, it shows in tegrastats as GR3D_FREQ @[0,1574,0]
  • When 3 GPCs are active, it shows as GR3D_FREQ @[1574,1574,1574].