diff options
Diffstat (limited to 'first-isofs/crt0.S')
| -rw-r--r-- | first-isofs/crt0.S | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/first-isofs/crt0.S b/first-isofs/crt0.S index a8a340c..2db1281 100644 --- a/first-isofs/crt0.S +++ b/first-isofs/crt0.S @@ -112,6 +112,25 @@ flush_icache: tst %i4 /* quit unless it's Sun4u */ be 0f nop + + /* Careful, we cannot read the %ver register on sun4v because + * there that register is hyperprivileged and we are executing + * in privileged mode. + * + * This early on it's difficult to portably detect sun4v as + * that requires OBP calls. So do this super-ugly trick of + * trying to set the PSTATE_AG bit in %pstate which will read + * back as zero on sun4u. + */ + rdpr %pstate, %l0 + or %l0, 0x1, %l1 + wrpr %l1, %pstate + rdpr %pstate, %l1 + wrpr %l0, %pstate + andcc %l1, 0x1, %g0 + be,pn %xcc, 0f + nop + rdpr %ver, %l0 srlx %l0, (32 + 16), %l1 cmp %l1, 0x3e |