2012/3/26 Asha R <rd.asha22@gmail.com>

I am new to UEFI and trying to understand working of UEFI on ARM platform.

On building UEFI, there are different binaries generated for each phase and also for drivers
eg: platformSec.efi, platformBds.efi and UsbDxe.efi,etc

Q1. Is UEFI flashed as single binary i.e., PlatformPkg.fd or different efi's?

I flash a single .fd onto my platforms.

Q1. As the code is in ROM (flash), I understand that it must be copied to RAM for execution.
Will complete UEFI be copied to RAM or some phase or section wise?

Q3. How does operating sysetm invoke the UEFI Runtime services?

Q4. I read in one of the internet link that other than Timer, there are no hardware interrupts.
Without hardware interrupt how will the USB kind of device be recognized?

UEFI has interrupt support for ARM platforms.