Hard Processor System Technical Reference Manual: Agilex™ 5 SoCs

ID 814346
Date 7/19/2024
Public

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5.1.7.1.2. Clock Manager Configurable Registers

You must configure various registers within the clock manager for the EMAC controller to perform properly. The following table provides a summary of the important clock manager register bits that control operation of the EMAC.
Table 170.  Clock Manager Settings
Register.Field Description
en.emacptpen emac_ptp_clk output enable.

en.emac0en

en.emac1en

en.emac2en

Enables clock emac0_clk, emac1_clk and emac2_clk output.
Note: There are corresponding ens and enr registers that allow the same fields to be set or cleared on a bit-by-bit basis.
bypass.emacptp
EMAC PTP clock bypass. This bit indicates if the emac_ptp_clk is bypassed to the input clock reference of the peripheral PLL.
  • 0x0 = No bypass occurs.
  • 0x1 = emac_ptp_clk is bypassed to the input clock reference of the main PLL.
Note: There are corresponding bypasss and bypassr registers that allow the same bits to be set or cleared on a bit-by-bit basis.

bypass.emaca

bypass.emacb

Clock bypass. This bit indicates whether emaca_free_clk or emacb_free_clk is bypassed to the input clock reference of the main PLL.
  • 0x0 = No bypass occurs.
  • 0x1 = emac*_free_clk is bypassed to the input clock reference of the main PLL.
Note: There are corresponding bypasss and bypassr registers that allow the same bits to be set or cleared on a bit-by-bit basis.

emacctl.emac0sel

emacctl.emac1sel

emacctl.emac2sel

EMAC clock source select. This bit selects the source for the emac* clk as either emaca_free_clk or emacb_free clk
  • 0x0 = emaca_free_clk
  • 0x1 = emacb_free_clk