| Virtual Accelerator Switchboard (VAS) |
| ===================================== |
| |
| This document provides information about using VAS from user space. |
| Applications send NX requests using COPY/PASTE instructions. NX raises |
| an interrupt when it sees fault on the request buffer. Kernel handles |
| the interrupt and process the fault. |
| |
| Skiboot allocates the IRQ and exports it with interrupts property. To |
| provide backward compatibility for older kernels, enable VAS user space |
| support with NVRAM command. |
| |
| nvram -p ibm,skiboot --update-config vas-user-space=enable |
| |
| This nvram config update is temporary and can be removed in future if |
| not needed. |