Why does toggling p0_pin_perst_n_i fail to reset PCI Express* links in the Agilex™ 5 FPGA E-Series ES devices in the Quartus® Prime Pro Edition Software version 24.2? - Why does toggling p0_pin_perst_n_i fail to reset PCI Express* links in the Agilex™ 5 FPGA E-Series ES devices in the Quartus® Prime Pro Edition Software version 24.2?
Description For a PCIe link in a transceiver bank, there are two pins in the HVIO banks with an optional function as PCIe platform reset (PERST#) for the PCIe link in the bank. You can connect PERST# to either one of the reset pins. The reset pin, not used as PERST#, can be used as a generic HVIO signal. For example, if pin PIN_PERST_N_CVP_L1A_0 in Bank 5A is connected to PERST# for the PCIe link in Bank L1A, pin PIN_PERST_N_CVP_L1A_1 in Bank 5B can be assigned as a generic HVIO signal. Due to a problem in the ES devices, assigning either of the two reset pins as PERST# fails to reset the PCIe link. Resolution For the Agilex™ 5 FPGA E-series in the current Quartus® Prime software release, you must assign both p0_pin_perst_n_i and p0_pin_perst_n_1_i ports to the location of the reset pins in HVIO banks as shown in the following table. Connect PERST# to either one of the reset pins. The other reset pin, not used as PERST#, must be left floating at the board level. For example, for a PCIe link in GTS bank L1B, assign p0_pin_perst_n_i to pin PIN_PERST_N_CVP_L1B_0 and assign p0_pin_perst_n_1_i to pin PIN_PERST_N_CVP_L1B_1 . If you connect PERST# to PIN_PERST_N_CVP_L1B_0 , leave PIN_PERST_N_CVP_L1B_1 floating at the board level. Tie the i_gpio_perst0_n port to logic high. Pin location assignment for p0_pin_perst_n_i and p0_pin_perst_n_1_i ports PCIe link in GTS Bank Pin perst port location assignment p0_pin_perst_n_i p0_pin_perst_n_1_i L1A PIN_PERST_N_CVP_L1A_0 PIN_PERST_N_CVP_L1A_1 L1B PIN_PERST_N_CVP_L1B_0 PIN_PERST_N_CVP_L1B_1 L1C PIN_PERST_N_CVP_L1C_0 PIN_PERST_N_CVP_L1C_1 R4A PIN_PERST_N_R4A_1 PIN_PERST_N_R4A_0 R4B PIN_PERST_N_R4B_1 PIN_PERST_N_R4B_0 R4C PIN_PERST_N_R4C_1 PIN_PERST_N_R4C_0 You must assign weak pull-down to pin preset ports in the Quartus® Prime Pro Software setting file. set_instance_assignment -name WEAK_PULL_DOWN ON -to < p0_pin_perst_n_i pin> set_instance_assignment -name WEAK_PULL_DOWN ON -to <p0_pin_perst_n_1_i pin> Additional Information This problem is fixed beginning with the Quartus® Prime Pro Edition software version 24.3.
Custom Fields values:
['novalue']
Errata
15014650145
False
['novalue']
['FPGA Dev Tools Quartus® Prime Software Pro']
24.3
23.4
['Agilex™ 5 FPGA E-Series']
['novalue']
['novalue']
['novalue'] - 2025-06-11
external_document