FW with 1MB TX buffer

[AlexeySaff]

Model Transmit Buffer Memory
Cisco Nexus SmartNIC K3P-S (formerly X25)
128KiB per port (256KiB total)
1MB per port (2MB in total) as a separately available firmware image. The images built with 1MB per port incur an additional port-to-wire latency of ~20ns

any ideas where I can find 1MB TX firmware image for X25?