sparc64: Add hypervisor interfaces for SPARC-T4 perf counter access.

Unlike for previous chips, access to the perf-counter control
registers are all hyper-privileged.  Therefore, access to them must go
through a hypervisor interface.

Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/arch/sparc/kernel/hvapi.c b/arch/sparc/kernel/hvapi.c
index 8593672..1032df4 100644
--- a/arch/sparc/kernel/hvapi.c
+++ b/arch/sparc/kernel/hvapi.c
@@ -45,6 +45,7 @@
 	{ .group = HV_GRP_NIU,					},
 	{ .group = HV_GRP_VF_CPU,				},
 	{ .group = HV_GRP_KT_CPU,				},
+	{ .group = HV_GRP_VT_CPU,				},
 	{ .group = HV_GRP_DIAG,		.flags = FLAG_PRE_API	},
 };
 
diff --git a/arch/sparc/kernel/hvcalls.S b/arch/sparc/kernel/hvcalls.S
index 58d60de..f3ab509 100644
--- a/arch/sparc/kernel/hvcalls.S
+++ b/arch/sparc/kernel/hvcalls.S
@@ -805,3 +805,19 @@
 	retl
 	 nop
 ENDPROC(sun4v_reboot_data_set)
+
+ENTRY(sun4v_vt_get_perfreg)
+	mov	%o1, %o4
+	mov	HV_FAST_VT_GET_PERFREG, %o5
+	ta	HV_FAST_TRAP
+	stx	%o1, [%o4]
+	retl
+	 nop
+ENDPROC(sun4v_vt_get_perfreg)
+
+ENTRY(sun4v_vt_set_perfreg)
+	mov	HV_FAST_VT_SET_PERFREG, %o5
+	ta	HV_FAST_TRAP
+	retl
+	 nop
+ENDPROC(sun4v_vt_set_perfreg)