From 7aa6264543f19ceea9b5f386242917296d63be05 Mon Sep 17 00:00:00 2001
From: "David S. Miller" <davem@sunset.davemloft.net>
Date: Sat, 11 Feb 2006 23:14:59 -0800
Subject: [SPARC64]: Do not try to write to %tick or %stick on SUN4V.
Writes by privileged code are disallowed. The hypervisor manages
the non-privileged bit.
Signed-off-by: David S. Miller <davem@davemloft.net>
---
arch/sparc64/kernel/time.c | 26 ++++++++++++++++----------
1 file changed, 16 insertions(+), 10 deletions(-)
diff --git a/arch/sparc64/kernel/time.c b/arch/sparc64/kernel/time.c
index 24681b9b44..7041146f86 100644
--- a/arch/sparc64/kernel/time.c
+++ b/arch/sparc64/kernel/time.c
@@ -193,16 +193,22 @@ struct sparc64_tick_ops *tick_ops __read_mostly = &tick_operations;
static void stick_init_tick(unsigned long offset)
{
- tick_disable_protection();
-
- /* Let the user get at STICK too. */
- __asm__ __volatile__(
- " rd %%asr24, %%g2\n"
- " andn %%g2, %0, %%g2\n"
- " wr %%g2, 0, %%asr24"
- : /* no outputs */
- : "r" (TICK_PRIV_BIT)
- : "g1", "g2");
+ /* Writes to the %tick and %stick register are not
+ * allowed on sun4v. The Hypervisor controls that
+ * bit, per-strand.
+ */
+ if (tlb_type != hypervisor) {
+ tick_disable_protection();
+
+ /* Let the user get at STICK too. */
+ __asm__ __volatile__(
+ " rd %%asr24, %%g2\n"
+ " andn %%g2, %0, %%g2\n"
+ " wr %%g2, 0, %%asr24"
+ : /* no outputs */
+ : "r" (TICK_PRIV_BIT)
+ : "g1", "g2");
+ }
__asm__ __volatile__(
" rd %%asr24, %%g1\n"
--
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