Visible to Intel only — GUID: sfo1410070149655
Ixiasoft
Visible to Intel only — GUID: sfo1410070149655
Ixiasoft
A.4.5. Clock Select
The boot ROM reads the clock select values to determine what frequency has been selected for the CPU clock and any interface clock during boot.
The clock select (CSEL) pins are asserted to select the speed of the HPS boot interface. If the FPGA is used as the boot source, the CSEL pins are ignored. The CSEL values define the main PLL, l2_mp_clk and l4_sp_clk. Based on the clock source and clock select settings, boot ROM configures the main PLL and peripheral PLL parameters and the clock dividers for clocks derived from the PLLs.