Question for CXL Drivers and ACPI required for a CXL mem device?

[samarth saxena]

Hi All,

I am trying to bring up a system with a CXL Type 3 device using Qemu.
I see that the device is visible in the operating system at the location:
             /dev/cxl/mem0
And a persistent memory attached to the device at
              /sys/bus/cxl/devices/mem0/pmem

But I am unable to understand how to use this memory (pmem).
How can the Linux map this Pmem instance to user space.
Also, CXL device can be a non persistent memory too. How will that be visible?

Which all drivers are necessary to use a CXL Type3 device as a memory
expander? Is there any ongoing development in the kernel?

Regards,
Samarth