No serial on Genesys 2 board

[newinnovations]

I am working with a Genesys 2 board and succeeded in creating the gateware using:

./make.py --board genesys2

Creating the bitstream and uploading it to the board using Vivado also went ok, and i see the chaser animation on the leds.

But I don't see any activity on the serial port. Looking at the generated verilog files, I noticed that there is no serial connection to the core:

module genesys2 (
    input  wire          clk200_n,
    (* dont_touch = "true" *)
    input  wire          clk200_p,
    input  wire          cpu_reset_n,
    output wire   [14:0] ddram_a,
    output wire    [2:0] ddram_ba,
    output wire          ddram_cas_n,
    output wire          ddram_cke,
    output wire          ddram_clk_n,
    output wire          ddram_clk_p,
    output wire          ddram_cs_n,
    output wire    [3:0] ddram_dm,
    inout  wire   [31:0] ddram_dq,
    inout  wire    [3:0] ddram_dqs_n,
    inout  wire    [3:0] ddram_dqs_p,
    output wire          ddram_odt,
    output wire          ddram_ras_n,
    output wire          ddram_reset_n,
    output wire          ddram_we_n,
    (* dont_touch = "true" *)
    input  wire          eth_clocks_rx,
    output wire          eth_clocks_tx,
    input  wire          eth_int_n,
    output wire          eth_mdc,
    inout  wire          eth_mdio,
    output wire          eth_rst_n,
    input  wire          eth_rx_ctl,
    input  wire    [3:0] eth_rx_data,
    output wire          eth_tx_ctl,
    output wire    [3:0] eth_tx_data,
    input  wire          sdcard_cd,
    output wire          sdcard_clk,
    inout  wire          sdcard_cmd,
    inout  wire    [3:0] sdcard_data,
    output wire          sdcard_rst,
    inout  wire    [7:0] usb_fifo_data,
    input  wire          usb_fifo_oe_n,
    output reg           usb_fifo_rd_n,
    input  wire          usb_fifo_rxf_n,
    input  wire          usb_fifo_siwua,
    input  wire          usb_fifo_txe_n,
    output reg           usb_fifo_wr_n,
    output wire          user_led0,
    output wire          user_led1,
    output wire          user_led2,
    output wire          user_led3,
    output wire          user_led4,
    output wire          user_led5,
    output wire          user_led6,
    output wire          user_led7
);

Looking at make.py, I see that a lot of boards get serial added to soc_capabilities during board class initialization. But the Genesys2 does not. Adding it manually made no difference.

Am I missing something here? Because I saw several people here posting serial logs from Genesys 2 boards.

Your help is greatly appreciated.

[tparng]

I am also working with Genesys2 board and have similiar issues. I can also upload bitstream to the Genesys2 board using Vivado. But if try to load the bitstream with command "$ ./make.py --board=genesys2 --cpu-count=4 --load", the command runs but nothing happened on the Genesys2 board (proramming done LED not light up and no chasing LEDs animation). Besides, the Load Linux Images over Serial command "$ litex_term --images=images/boot.json /dev/ttyUSB0" did not not work either (It just freezed there, nothing happened.). It seems that the JTAG or litex_term conection is OK but bitstream or linux image programming is not done successfully (or not even started at all).

[tparng]

@newinnovations,

I encountered the same issue as you. After digging into the code, I found the serial io pads are mistakenly (due to bugs or other reasons) taken by usb_fifo. Therefore I fixed the bug by adding "serial” (this may be not necessary)and remove “usb_fifo” in class Genesys2(Board) in make.py :

class Genesys2(Board):
def init(self):
from litex_boards.targets import digilent_genesys2
Board.init(self, digilent_genesys2.BaseSoC, soc_capabilities={
# Communication
"serial",
#"usb_fifo",
"ethernet",
# Storage
"sdcard",
})

Now, I can do serial boot successfully for linux-on-litex-vexriscv.
You can take a try!

BTW, if you also want to try booting on Ethernet, remember to have your tftp server configured to have a BLOCKSIZE of 1024 as ~/litex/litex/soc/software/libliteeth/tftp.c has it pre-defined to be 1024:
#define BLOCK_SIZE 1024 /* block size in bytes 512 or 1024*/

Tparng