Microsoft has released a new firmware for all Surface Pro 4 devices. These updates are usually provided via the Windows Update service, and are delivered in stages to Surface customers. So, if the update is not available on your machine now, don’t worry, it should be available in the coming days.
In case not, please manually check Windows Update later.
Here’s the changelog for May 25 release
Windows Update History Name
Device Manager Name
Microsoft Driver update for Surface Embedded Controller Firmware
Surface Embedded Controller Firmware
Intel Corporation driver update for Intel(R) Precise Touch Device
Intel(R) Precise Touch Device
Surface driver update for Surface Integration
Microsoft driver update for Surface Touch Servicing ML
Surface Touch Servicing ML
Surface driver update for Surface System Aggregator
Surface System Aggregator
Surface driver update for Surface UEFI
Microsoft Driver update for Surface Touch
Alternatively, you can visit the Microsoft Download Center to download the Surface Pro 4 update (msi file) manually, but this is recommended for advanced users or enterprise deployment or at least for a user who knows how to deal with it.