Recent Discussions
Stratix-10G FPGA Transceiver Configuration for Ethernet MAC 100G Controller
Hi, We need to validate our custom built Ethernet MAC 100G controller core on Stratix-10G FPGA. We are planning to use the in-built FPGA transceiver for the PHY functionality. From the IP catalog, we selected "L-Tile/H-Tile Transceiver Native PHY Stratix 10 IP" and tried to configure for Ethernet MAC 100G. But we couldn't find any preset configuration which supports either 100G or 25G line rate. Could you pl. suggest what preset configuration to be used? Pl. note that our Ethernet MAC 100G controller core supports 256-bit data path. Thanks, Sunil
PCIe Enumeration Failure for CXL IP
When attempting to validate the Agilex 7 R-Tile Compute Express Link (CXL) 1.1/2.0 IP (Type 2 and Type 3) using a CXL compatible host server, the host server is unable to complete PCIe bus enumeration. The host server stalls while attempting to complete PCIe bus enumeration. The stall never resolves after boot, and access to to the host is never granted. Depiction of the stall and its status code from the host server's perspective is provided as an attached PNG file titled: "pcie_enumeration_stall". Debugging Information: A PCIe Gen 5.0 reference design using the Altera R-Tile Avalon Streaming IP For PCI Express was used to validate that PCIe enumeration could complete fully without failure, and that the host server could exchange data with the FPGA. While running the CXL example design, the Quartus System Console's Link Logger indicates that the LTSSM state is in the "UP_L0" before the PCIe bus enumeration stall. The state may sometimes change when attempting to "Refresh" the status during the PCIe bus enumeration stall. The state may briefly enter recovery (UP_L0 -> REC_IDLE -> REC_RCVRCFG -> REC_RCSVLOCK -> REC_COMPLETE -> UP_L0). Depiction of the Quartus System Console's Link Logger when this occurs is provided as an attached PNG file titled: "ltssm_link_logger". While running the CXL example design, the Quartus System Console's Link Logger indicates that the advertised and negotiated link speeds and widths are both 32.0 GT and x16. Depiction of a CXL Type 3 Quartus System Console's Overview is provided as an attached PNG file titled: "cxl_ip_systemconsole_overview". Instead of generating the example design, the pre-compiled binary offered by Altera for Type 2 and Type 3 CXL IP designs was used and resulted in the exact same failures as shown above. CXL.mem transaction registers (M2S and S2M) are 0x00, indicating that the host server never progresses far enough to begin sending/receiving transactions/requests. Between the PCIe build that functions and the CXL build that does not function (stalls at enumeration), no server UEFI settings were changed. A CXL enable function was enabled for all tests. Several PCIe UEFI settings were changed in an attempt to resolve the enumeration stall, but none changed the outcome. Attempting to disable the CXL Compliance 2.0 and the HDM decoder registers both did not resolve the issue. The FPGA was powered and programmed before the server was launched. Two different CXL servers were tested and both resulted in the same behavior. The relevant PCIe and CXL settings from BIOS is provided as an attached PNG file titled: "cxl_server_settings". The CXL REFCLK was tested as both COMMON and SRIS/SRNS. Each test changed SW3 to use relevant onboard and connected based clocks. IP Settings: CXL IP settings are uploaded as PNG files titled: "cxl_ip_settings_N". The settings tested are the default provided settings as well as a version with a 300 MHz PLD clock (SRIS). Hardware Details: FPGA is connected to host server via PCIe Gen 5.0 x16 slot on Tile 14C. FPGA device is the Altera Agilex 7 FPGA I-Series Development Kit (Production 2x R-Tile & 1x F-Tile) (AGIB027R29A1E1VB) The DIMM provided with the development kit is slotted into DIMM Slot A. SW1 is set to 1000 (PCIe PRSNT x16). SW3 is set to 0110 for designs using the CXL/PCIe common clock and 0000 for designs using the CXL/PCIe onboard REFCLK (SRIS). Software Details: Quartus Prime Pro Edition v25.1 was used to generate the designs. R-Tile Altera FPGA IP for Compute Express Link (CXL) was generated with version 1.17.0. FPGA Design: The FPGA design is generated using the example design with the IP settings given above. A pre-compiled binary provided by Altera was also used to test instead of a generated design. Server details: SMC AS-1126HS-TN (CXL 2.0 via 4x PCIe gen5 x16 slots) CPU: 2x AMD EPYC 9135 (CXL 2.0) RAM: 4x Micron 64GB @ 6000 MT/s UEFI: AMI 1.7a 10/30/2025 Attachments: The system console debug register outputs are saved to CSV files attached to this post. These CSV files are taken from a CXL Type 3 reference design with PLD REFCLK at 300 MHz (SRIS). Questions: Can you provide guidance on how to obtain more information on the enumeration status other than the LTSSM register? Can you provide the UEFI/BIOS settings for PCIe/CXL that was used to test this IP as reference? Could the configuration space registers (DVSEC/HDM) or the TLP handling implemented in the CXL example design RTL create this PCIe enumeration failure? Can you provide guidance on what debug/status registers the CXL IP provides that could be relevant to this issue?Regarding the TX settings of MIPI CSI2 IP
In my Qsys project, I want to implement a function where the Test Pattern Generator IP sends the pattern to the MIPI CSI2 TX via an AXI stream. The MIPI CSI2 TX then sends the pixel data to link1 of the MIPI DPHE. After looping back, link0 of the MIPI DPHE sends the data to the MIPI CSI2 RX via the MIPI interface. However, strangely, the MIPI CSI2 TX axi stream ready signal remains low, and it doesn't process axi stream data from the TPG. The MIPI CSI2 TX settings are shown in the figure. What could be causing this phenomenon? Any help is appreciated.
Regarding MIPI CSI 2 TX
Hi, In my Project, I have to generate test pattern data and send it to MIPI CSI 2 via AXI stream, and MIPI CSI 2 will send the pixel data to link_0 of MIPI DPHY IP , but when i try to simulate the design(includes MIPI CSI 2 and MIPI DHPY IP interconnected), mipi_dphy_0/LINK0_CK_Stopstate is constantly high, I guess this signal is supposed to go low after T INT time, and also ready Singal from axi_stream is asserted low after being high for three clock cycles, i didn't understand why. Any help is appreciated.
Confusion for TX Clock direction for Triple Speed 1G Ethernet IP?
Hello ALTRA IP experts, Can anybody please explain to me why, when i set the Triple Speed Ethernet IP up for RGMII mode, the tx clock for the MAC is set as an input? eth_tse_0_pcs_mac_tx_clock_clk : in std_logic := 'X'; -- clk I was expecting this signal to be an output for the Transmit MAC section to to the PHY TX block ? Here are all of the signal connections i get when i setup in RMII mode for the Triple Speed 10/100/1000 Ethernet IP core (its easier to see directions and sizes using the VHDL instance template) : eth_tse_0_mac_status_set_10 : in std_logic := 'X'; -- set_10 eth_tse_0_mac_status_set_1000 : in std_logic := 'X'; -- set_1000 eth_tse_0_mac_status_eth_mode : out std_logic; -- eth_mode eth_tse_0_mac_status_ena_10 : out std_logic; -- ena_10 eth_tse_0_mac_rgmii_rgmii_in : in std_logic_vector(3 downto 0) := (others => 'X'); -- rgmii_in eth_tse_0_mac_rgmii_rgmii_out : out std_logic_vector(3 downto 0); -- rgmii_out eth_tse_0_mac_rgmii_rx_control : in std_logic := 'X'; -- rx_control eth_tse_0_mac_rgmii_tx_control : out std_logic; -- tx_control eth_tse_0_receive_data : out std_logic_vector(31 downto 0); -- data eth_tse_0_receive_endofpacket : out std_logic; -- endofpacket eth_tse_0_receive_error : out std_logic_vector(5 downto 0); -- error eth_tse_0_receive_empty : out std_logic_vector(1 downto 0); -- empty eth_tse_0_receive_ready : in std_logic := 'X'; -- ready eth_tse_0_receive_startofpacket : out std_logic; -- startofpacket eth_tse_0_receive_valid : out std_logic; -- valid eth_tse_0_transmit_data : in std_logic_vector(31 downto 0) := (others => 'X'); -- data eth_tse_0_transmit_endofpacket : in std_logic := 'X'; -- endofpacket eth_tse_0_transmit_error : in std_logic := 'X'; -- error eth_tse_0_transmit_empty : in std_logic_vector(1 downto 0) := (others => 'X'); -- empty eth_tse_0_transmit_ready : out std_logic; -- ready eth_tse_0_transmit_startofpacket : in std_logic := 'X'; -- startofpacket eth_tse_0_transmit_valid : in std_logic := 'X'; -- valid eth_tse_0_mac_mdio_mdc : out std_logic; -- mdc eth_tse_0_mac_mdio_mdio_in : in std_logic := 'X'; -- mdio_in eth_tse_0_mac_mdio_mdio_out : out std_logic; -- mdio_out eth_tse_0_mac_mdio_mdio_oen : out std_logic; -- mdio_oen eth_tse_0_mac_misc_magic_wakeup : out std_logic; -- magic_wakeup eth_tse_0_mac_misc_magic_sleep_n : in std_logic := 'X'; -- magic_sleep_n eth_tse_0_mac_misc_ff_tx_crc_fwd : in std_logic := 'X'; -- ff_tx_crc_fwd eth_tse_0_mac_misc_ff_tx_septy : out std_logic; -- ff_tx_septy eth_tse_0_mac_misc_tx_ff_uflow : out std_logic; -- tx_ff_uflow eth_tse_0_mac_misc_ff_tx_a_full : out std_logic; -- ff_tx_a_full eth_tse_0_mac_misc_ff_tx_a_empty : out std_logic; -- ff_tx_a_empty eth_tse_0_mac_misc_rx_err_stat : out std_logic_vector(17 downto 0); -- rx_err_stat eth_tse_0_mac_misc_rx_frm_type : out std_logic_vector(3 downto 0); -- rx_frm_type eth_tse_0_mac_misc_ff_rx_dsav : out std_logic; -- ff_rx_dsav eth_tse_0_mac_misc_ff_rx_a_full : out std_logic; -- ff_rx_a_full eth_tse_0_mac_misc_ff_rx_a_empty : out std_logic; -- ff_rx_a_empty clk_out_5_clk : out std_logic; -- clk eth_tse_0_pcs_mac_tx_clock_clk : in std_logic := 'X'; -- clk eth_tse_0_pcs_mac_rx_clock_clk : in std_logic := 'X'; -- clk eth_tse_0_mac_clkena_rx_clkena : in std_logic := 'X'; -- rx_clkena eth_tse_0_mac_clkena_tx_clkena : in std_logic := 'X' -- tx_clkena These all make sense to me EXCEPT for the eth_tse_0_pcs_mac_tx_clock_clk signal which i thought would be an OUPUT and NOT and INPUT ! Thanks for your help, BarryCorrect way to configure the RGMII input and output pins on a MAX10 FPGA
Greetings ALTERA Expetrs, I am using an ALTERA Triple Speed Ethernet IP core configured n MAC only mode, which talks to a MARVELL 88E1111 PHY. Actually for this example i am using an ALTERA MAX10 10M50-C Development kit. I am having trouble understanding exactly HOW to configure the DDR RGMII input and output pins. After instantiating the Triple Speed Ethernet IP in a top level System Verilog file and connecting up Avalon MM, Avalon Tx/Rx ST interfaces etc, and connecting up clocks and resets, do i need to to connect up my RGMII DDR outputs using altddio_out IP and my RGMII DDR inputs to FPGSA pins using altddio_in IP blocks ? This is how i am thinking i need to connect my DDR RGMII FPGA pins up to my Triple Speed Ethernet RGMII tx in and rx in busses on the IP: Connect the TX Clock output : altddio_out #(.width(1), .INTENDED_DEVICE_FAMILY("max10")) altddio_out_a_txc (.outclock (clk_125MHz), .datain_h (1'b1), .datain_l (1'b0),.dataout (RGMII_ETH_TXC), // TSE clock TX PORT A .oe (1'b1), .outclocken (1'b1), .aclr (1'b0), .aset (1'b0) ); Connect the RGMI TX data outputs : altddio_out #( .width(4), .INTENDED_DEVICE_FAMILY("max10") ) altddio_out_a_txd ( .outclock (clk_125MHz), // 125 MHz Transmit clock for RGMII .datain_h (rgmii_out_ddr), // rising edge .datain_l (rgmii_out_ddr), // falling edge .dataout (rgmii_out), .aclr (1'b0), .aset (1'b0), .oe (1'b1), .outclocken (1'b1) ); Where in the above code rgmii_out wires are going to FPGA DDR RGMI TX output pins, and rgmii_out_ddr is from the Triple speed IP core. For the RX side for the INPUT DDR RGIM Rx data bus: altddio_in #(.width(4), .INTENDED_DEVICE_FAMILY("max10")) altddio_in_a_rxd ( .inclock (RGMII_ETH_RXC), .datain (rgmii_in), .dataout_h (rgmii_rxd), .dataout_l (/* unused */) ); Do these sort of DDR interface IP instantiations looks correct ? All help gratefully received ! Thanks, Dr Barry H
How to Prevent Agilex 7 F-tile PMA Direct PHY TX Lane Skew
Hi, We are implementing a 16-lane custom 1.0125 Gbps TX with F-tile PMA Direct PHY IP. The 16 lanes should be bonded together and they need to have a skew of less than 0.05 UI. However, we simulated the TX and found the serial output of each lane had skew of up to 11 ns, despite the fact that they had sychronized parallel input data. We have followed the suggested settings in user guide to enable system bonding, such as Number of Lanes=16, PMA Width=16, and Selected tx_clkout clock source=Bond Clock. For IP port connection, we use tx_clkout[0] as the source of all 16 tx_coreclkin. We also use it to clock all 16 parallel input data of TX in FPGA core fabric to make sure they are synchronized. Our IP Parameter and waveform is as attched. In testbench we feed parallel input data to all 16 lanes at the same time. We also assert TX PMA Interface Data Valid bit [38]. However, the serial output of each lane seems to start at different point of time, creating skew. Is this model behavior or actual hardware behavior? We tested on development board and our target sink is unable to lock to TX serial output as expected. Is there any way to eliminate the skew? Below is quartus version and our target board. Quartus Version : 25.3 Target Board : AGIC040R39A2E2VR0 Thanks wentsung
Agilex 7 R-Tile CXL Type-2 IP Hang with Incomplete CXL.cache Operations
Device: DK-DEV-AGI027RBES (Power Solution 2) Software Version: Quartus Prime Pro 24.3 IP Core: CXL Type 2 Hard IP Issue Description: We observed that the CXL Type-2 IP can hang when CXL.cache transactions remain incomplete under heavy workloads. Our design is based on the CXL Type-2 design example, with a delay unit inserted between the CXL IP and the DDR controller. We ran Intel MLC bandwidth tests on the CXL device while monitoring host reachability using continuous ping. In the first experiment (Figure 1), the delay unit inserted a 10,000-cycle delay for each CXL.mem request, with no CXL.cache operations involved. In this case, ping latency increased from approximately 0.2 ms to 45 ms, but the system remained stable. In the second experiment (Figure 2), we replaced the 10,000-cycle delay with a CXL.cache operation, which typically completes in around 300 cycles. Under this configuration, the system hung and ping indicated that the host became unreachable. We observed that the CXL.cache request was issued but never received a response, leading to the hang. We would like to know if there is a known issue or recommended solution for handling incomplete CXL.cache operations in this scenario.About Dual Simplex for Agilex 3
In the" GTS Transceiver Dual Simplex Interfaces User Guide: Agilex™ 3 and Agilex™ 5 FPGAs and SoCs", Note 3 in Table 2, Section 2. Overview, states the following: "DS mode is not currently supported for Agilex™ 3 FPGAs for this protocol." Which future version of Quartus Prime will support Agilex 3 ？ https://www.intel.com/content/www/us/en/docs/programmable/825853/25-1/overview.html
