Hard Processor System Technical Reference Manual: Agilex™ 5 SoCs

ID 814346
Date 7/19/2024
Public
Document Table of Contents

7.6.8. H2F User Clock Group

The H2F clocks are generated in the HPS and provided to the FPGA. These clocks connect to the FPGA fabric using the GCLKs, RCLKs, and PCLKs:

  • Global clock (GCLK): These clocks use global routing resources in the FPGA.
  • Regional clock (RCLK): These clocks route only to part of the chip, for example the entire FPGA width and height of I/O tiles.
  • Periphery clock (PCLK): These clocks are for high speed I/O interfaces.

The following diagram shows the H2F user clock group.

Figure 264. H2F User Clock Group Block Diagram

The following table shows the clock information for the H2F user clock group.

Table 307.  H2F User Clocks
Clock Name HPS Clock Source Clock Destination Description
h2f_user0_clk Clock manager FPGA LE General purpose use
h2f_user1_clk Clock manager FPGA LE General purpose use

tpiu_trace_clk_hio,

tpiu_trace_clk_div2

TPIU FPGA LE -> Pin Trace clock generated by TPIU, ½ of tpiu_trace_clkin. Also duplicated output on FPGA interface left.
emac0_phy_txclk_o_hio EMAC 0 FPGA LE -> Pin Transmit clock for EMAC 0 when FPGA interface is used instead of HPS I/O pins
emac1_phy_txclk_o_hio EMAC 1 FPGA LE -> Pin Transmit clock for EMAC 1 when FPGA interface is used instead of HPS I/O pins
emac2_phy_txclk_o_hio EMAC 2 FPGA LE -> Pin Transmit clock for EMAC 2 when FPGA interface is used instead of HPS I/O pins

The following table shows the registers used to program the clocks.

Table 308.  Programming Clock Registers
Clock Name *.src *.cnt (n+1 divider) *.div (2^n divider) Clock Gate (enable)
h2f_user0_clk

ctlgrp.s2fuser0ctr.src

= 0 (Main_PLL_C1)

= 1 (Peri_PLL_C3)

ctlgrp.s2fuser0ctr.cnt --- mainpllgrp.en.s2fuser0clken
h2f_user1_clk

ctlgrp.s2fuser1ctr

= 0 (Main_PLL_C1)

= 1 (Peri_PLL_C3)

ctlgrp.s2fuser1ctr.cnt --- perpllgrp.en.s2fuser1clken