VALID_START_PFN_4
psize_t npages4 = (VALID_END_PFN_4 - VALID_START_PFN_4);
ATF_REQUIRE_EQ(uvm_physseg_plug(VALID_START_PFN_4, npages4, &upm4), true);
psize_t npages2 = (VALID_END_PFN_4 - VALID_START_PFN_4);
for(pf = VALID_START_PFN_4; pf < VALID_END_PFN_4; pf += PF_STEP) {
if(pa < ctob(VALID_START_PFN_4))
pa += ctob(VALID_START_PFN_4);