2.4 About the P2Q Converter

The P-Channel to Q-Channel Converter (P2Q) converts a single P-Channel to a single Q-Channel. The P2Q uses the maximum 8-bit width for PSTATE and 32-bit for PACTIVE.

The following figure shows the main interfaces on the P2Q.

Figure 2-5 P2Q overview
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The P2Q receives power mode requests on its control P-Channel. The P2Q uses the device Q-Channel (dev_* signals) to send requests to the device. The P2Q uses clk_qactive_o to indicate when it requires a clock signal, clk.

The control P-Channel supports the all the PPU power modes and 16 operating modes. The implementer uses the CTRL_P_CH_PWR_PSTATE_MAP[15:0] and CTRL_P_CH_OP_PSTATE_MAP[15:0] configuration parameters, to choose which power modes and operating modes generate a quiescence request. See 2.4.1 P2Q configuration parameters.

clk_qactive_o is a Q-Channel signal that is HIGH:

When the P2Q becomes idle, then clk_qactive_o goes LOW and the clk input can be gated to reduce dynamic power.

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