Following is an example function call sequence to call the Hypervisor.

mflr r0
stw  r0,4(r1)

load r3  with parameter 1
load r4  with parameter 2
load r5  with parameter 3
load r6  with parameter 4
load r7  with parameter 5
load r8  with parameter 6
load r9  with parameter 7
load r10 with parameter 8

load r11 with API Function Number

sc   1   

extsw r3, r3

save result 1 from r4
save result 2 from r5
save result 3 from r6
save result 4 from r7
save result 5 from r8
save result 6 from r9
save result 7 from r10
save result 8 from r11 (rare, but it's in the ABI as available)

lwz  r0, 4(r1)
mtlr r0
blr