On Tue, May 18, 2021 at 05:36:18PM +0100, Sudeep Holla wrote: > SMCCC v1.2 allows x8-x17 to be used as parameter registers and x4—x17 > to be used as result registers in SMC64/HVC64. Arm Firmware Framework > for Armv8-A specification makes use of x0-x7 as parameter and result > registers. There are other users like Hyper-V who intend to use beyond > x0-x7 as well. Reviewed-by: Mark Brown