[PATCH] sun4m SMP: fix wrong shift instruction in IPI handler

[PATCH] sun4m SMP: fix wrong shift instruction in IPI handler

[Will Simoneau]

This shift instruction appears to be shifting in the wrong direction.
Without this change, my SparcStation-20MP hangs just after bringing up
the second CPU:

Entering SMP Mode...
Starting CPU 2 at f02b4e90
Brought up 2 CPUs
Total of 2 processors activated (99.52 BogoMIPS).
   *** stuck ***

Signed-off-by: Will Simoneau <simoneau@ele.uri.edu>
---
 arch/sparc/kernel/entry.S |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/arch/sparc/kernel/entry.S b/arch/sparc/kernel/entry.S
index 9fe08a1..f445e98 100644
--- a/arch/sparc/kernel/entry.S
+++ b/arch/sparc/kernel/entry.S
@@ -293,7 +293,7 @@ maybe_smp4m_msg:
 	WRITE_PAUSE
 	wr	%l4, PSR_ET, %psr
 	WRITE_PAUSE
-	sll	%o3, 28, %o2		! shift for simpler checks below
+	srl	%o3, 28, %o2		! shift for simpler checks below
 maybe_smp4m_msg_check_single:
 	andcc	%o2, 0x1, %g0
 	beq,a	maybe_smp4m_msg_check_mask

Re: [PATCH] sun4m SMP: fix wrong shift instruction in IPI handler

[David Miller]

From: Will Simoneau <simoneau@ele.uri.edu>
Date: Fri, 15 Jul 2011 23:05:15 -0400

> This shift instruction appears to be shifting in the wrong direction.
> Without this change, my SparcStation-20MP hangs just after bringing up
> the second CPU:
> 
> Entering SMP Mode...
> Starting CPU 2 at f02b4e90
> Brought up 2 CPUs
> Total of 2 processors activated (99.52 BogoMIPS).
>    *** stuck ***
> 
> Signed-off-by: Will Simoneau <simoneau@ele.uri.edu>

Applied, thanks a lot Will.

Re: [PATCH] sun4m SMP: fix wrong shift instruction in IPI handler

[David Miller]

From: David Miller <davem@davemloft.net>
Date: Sat, 16 Jul 2011 10:46:36 -0700 (PDT)

> From: Will Simoneau <simoneau@ele.uri.edu>
> Date: Fri, 15 Jul 2011 23:05:15 -0400
> 
>> This shift instruction appears to be shifting in the wrong direction.
>> Without this change, my SparcStation-20MP hangs just after bringing up
>> the second CPU:
>> 
>> Entering SMP Mode...
>> Starting CPU 2 at f02b4e90
>> Brought up 2 CPUs
>> Total of 2 processors activated (99.52 BogoMIPS).
>>    *** stuck ***
>> 
>> Signed-off-by: Will Simoneau <simoneau@ele.uri.edu>
> 
> Applied, thanks a lot Will.

BTW, in the future please post sparc patches to
sparclinux@vger.kernel.org so that they 1) go to the correct audience
and 2) get tracked properly at patchwork.ozlabs.org

Thanks