From 1c2f61d40b691789626489fa947a3e003c9a84be Mon Sep 17 00:00:00 2001
From: "David S. Miller" <davem@davemloft.net>
Date: Thu, 5 Feb 2009 23:59:04 -0800
Subject: [PATCH] sparc64: Don't hook up pcr_ops on spitfire chips.

They can't be used for profiling and NMI watchdog currently
since they lack the counter overflow interrupt.

Signed-off-by: David S. Miller <davem@davemloft.net>
---
 arch/sparc/kernel/pcr.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/arch/sparc/kernel/pcr.c b/arch/sparc/kernel/pcr.c
index 92e0dda141a4a..1ae8cdd7e7032 100644
--- a/arch/sparc/kernel/pcr.c
+++ b/arch/sparc/kernel/pcr.c
@@ -133,11 +133,16 @@ int __init pcr_arch_init(void)
 
 	case cheetah:
 	case cheetah_plus:
-	case spitfire:
 		pcr_ops = &direct_pcr_ops;
 		pcr_enable = PCR_SUN4U_ENABLE;
 		break;
 
+	case spitfire:
+		/* UltraSPARC-I/II and derivatives lack a profile
+		 * counter overflow interrupt so we can't make use of
+		 * their hardware currently.
+		 */
+		/* fallthrough */
 	default:
 		err = -ENODEV;
 		goto out_unregister;