[PATCH 3/6] score/cpu/or1k: Follow no_cpu ISR_Handler algorithm.

[Hesham ALMatary]

This patch adjusts ISR_Handler to exactly follow the pseudo code introduced
in
http://rtems.org/onlinedocs/doc-current/share/rtems/html/porting/Interrupts-Interrupt-Dispatching.html
It adds two new checkings on _Thread_Dispatch_disable_level and _ISR_Nest_level
after returning from the C handler.
---
 cpukit/score/cpu/or1k/or1k-exception-handler-low.S | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/cpukit/score/cpu/or1k/or1k-exception-handler-low.S b/cpukit/score/cpu/or1k/or1k-exception-handler-low.S
index b18c4a3..eb279d0 100644
--- a/cpukit/score/cpu/or1k/or1k-exception-handler-low.S
+++ b/cpukit/score/cpu/or1k/or1k-exception-handler-low.S
@@ -149,6 +149,16 @@ jump_to_c_handler:
   l.sw    0(r6), r5
   l.sw    0(r8), r7
   
+  /* Check if _ISR_Nest_level > 0 */
+  l.sfgtui r5, 0
+  l.bf exception_frame_restore
+  l.nop
+  
+  /* Check if _Thread_Dispatch_disable_level > 0 */
+  l.sfgtui r7, 0
+  l.bf exception_frame_restore
+  l.nop
+  
   /* Check if dispatch needed */
   l.movhi r31, hi(DISPATCH_NEEDED)
   l.ori   r31, r31, lo(DISPATCH_NEEDED)
-- 
1.9.3