Hi Michael, On Wed, May 05, 2021 at 03:28:56PM +0000, Michael Kelley wrote: > From: Sudeep Holla <sudeep.holla@xxxxxxx> Sent: Wednesday, May 5, 2021 2:39 AM > > > > 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. > > > > Current SMCCC interface in the kernel just use x0-x7 as parameter and > > x0-x3 as result registers as required by SMCCCv1.0. Let us add new > > interface to support this extended set of input/output registers namely > > x0-x17 as both parameter and result registers. > > [...] > I've tested the new arm_smccc_1_2_hvc() function in the context > of Linux guests making hypercalls on Hyper-V for ARM64, and it > works as intended. But note that my test case only uses X0 thru X7. > > Tested-by: Michael Kelley <mikelley@xxxxxxxxxxxxx> > Reviewed-by: Michael Kelley <mikelley@xxxxxxxxxxxxx> Thanks! -- Regards, Sudeep
