Microchip 8250 based serial port

modulename: 8250_pci1xxxx.ko

configname: CONFIG_SERIAL_8250_PCI1XXXX

Linux Kernel Configuration
└─>Device Drivers
└─>Character devices
└─>Serial drivers
└─>PCI support
└─>Microchip 8250 based serial port
In linux kernel since version 6.3 (release Date: 2023-04-23)  
Select this option if you have a setup with Microchip PCIe
Switch with serial port enabled and wish to enable 8250
serial driver for the serial interface. This driver support
will ensure to support baud rates upto 1.5Mpbs.

source code: