How to disable the ConnectX on MNV303611A-EDLT?

[notooth]

The ConnectX temperature on my MNV303611A-EDLT card is very hot (95 C). How can I disable it? I just need to use the FPGA.

[mwrnd]

I am unaware of any way to do this. The ConnectX-5 IC includes a PCIe switch that hosts the FPGA and the two GbE interfaces so it cannot be fully disabled. From experience, it gets MUCH hotter if either of the ethernet interfaces are in use.

lspci      | grep -i "Xilinx\|Mellanox"
lspci -tv  | grep -i "Xilinx\|Mellanox"

01:00.0 PCI bridge: Mellanox Technologies MT28800 Family [ConnectX-5 PCIe Bridge]
02:08.0 PCI bridge: Mellanox Technologies MT28800 Family [ConnectX-5 PCIe Bridge]
02:10.0 PCI bridge: Mellanox Technologies MT28800 Family [ConnectX-5 PCIe Bridge]
03:00.0 Class 2000: Mellanox Technologies Innova-2 Flex Burn image
04:00.0 Ethernet controller: Mellanox Technologies MT27800 Family [ConnectX-5]
04:00.1 Ethernet controller: Mellanox Technologies MT27800 Family [ConnectX-5]

    +-1d.0-[01-04]----00.0-[02-04]--+--08.0-[03]----00.0  Mellanox Technologies Innova-2 Flex Burn image
    |                               \--10.0-[04]--+-00.0  Mellanox Technologies MT27800 Family [ConnectX-5]
    |                                             \-00.1  Mellanox Technologies MT27800 Family [ConnectX-5]

Your best bet is to come up with a Cooling Solution. The Innova-2 is designed for use in servers with 300-800 LFM of airflow.

Consider exploring the ConnectX registers. Dump them all with the following command:

sudo mst start
sudo mst status
sudo mlxreg -d /dev/mst/mt4119_pciconf0 --show_regs | cut -d " " -f 1 | grep "^[A-Z]" | grep -v "Available" | xargs -t -L 1 -I{} sudo mlxreg -d /dev/mst/mt4119_pciconf0 --show_reg {}

POWER_SETTINGS and PORT_STATE_BEHAVIOR seem like they may be useful.

sudo mlxreg -d /dev/mst/mt4119_pciconf0 --show_reg POWER_SETTINGS

 Field Name            | Address (Bytes) | Offset (Bits) | Size (Bits) | Access
 ==============================================================================
 power_settings_level  | 0x00000000      | 0             | 8           | RW
 ==============================================================================


sudo mlxreg -d /dev/mst/mt4119_pciconf0 --show_reg PORT_STATE_BEHAVIOR

 Field Name                 | Address (Bytes) | Offset (Bits) | Size (Bits) | Access
 ===================================================================================
 enforce_port_state_enabled | 0x00000000      | 31            | 1           | RW
 ===================================================================================