powernv: Fix OPAL tracepoint code
Patch c49f63530bb6 ("powernv: Add OPAL tracepoints") has a spurious
store to the stack:
ld r12,opal_tracepoint_refcount@toc(r2); \
std r12,32(r1); \
The store was originally used to save the current tracepoint status
so the entry and the exit tracepoints were always balanced. In the
end I just created a separate path when tracepoints are enabled.
The offset on the stack used for this store is not valid for ABIv2
and it causes strange issues. I noticed it because OPAL console input
was broken.
Fixes: c49f63530bb6 ("powernv: Add OPAL tracepoints")
Cc: <stable@vger.kernel.org> # v3.17+
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Anton Blanchard