diff options
Diffstat (limited to 'c/src/lib/libbsp/sparc/shared/irq_asm.S')
| -rw-r--r-- | c/src/lib/libbsp/sparc/shared/irq_asm.S | 57 |
1 files changed, 49 insertions, 8 deletions
diff --git a/c/src/lib/libbsp/sparc/shared/irq_asm.S b/c/src/lib/libbsp/sparc/shared/irq_asm.S index bf2dca9787..2ab0defa72 100644 --- a/c/src/lib/libbsp/sparc/shared/irq_asm.S +++ b/c/src/lib/libbsp/sparc/shared/irq_asm.S @@ -7,6 +7,8 @@ * COPYRIGHT (c) 1989-2011. * On-Line Applications Research Corporation (OAR). * + * Copyright (c) 2014 embedded brains GmbH + * * The license and distribution terms for this file may be * found in the file LICENSE in this distribution or at * http://www.rtems.org/license/LICENSE. @@ -165,17 +167,18 @@ done_flushing: #if defined(RTEMS_SMP) ! The executing context no longer executes on this processor - stb %g0, [%o0 + SPARC_CONTEXT_CONTROL_IS_EXECUTING_OFFSET] + st %g0, [%o0 + SPARC_CONTEXT_CONTROL_IS_EXECUTING_OFFSET] + + ! Try to update the is executing indicator of the heir context + mov 1, %g1 + +try_update_is_executing: - ! Wait for heir context to stop execution -1: - ldub [%o1 + SPARC_CONTEXT_CONTROL_IS_EXECUTING_OFFSET], %g1 + swap [%o1 + SPARC_CONTEXT_CONTROL_IS_EXECUTING_OFFSET], %g1 cmp %g1, 0 - bne 1b - mov 1, %g1 + bne check_is_executing - ! The heir context executes now on this processor - stb %g1, [%o1 + SPARC_CONTEXT_CONTROL_IS_EXECUTING_OFFSET] + ! The next load is in a delay slot, which is all right #endif ld [%o1 + G5_OFFSET], %g5 ! restore the global registers @@ -203,6 +206,44 @@ done_flushing: jmp %o7 + 8 ! return nop ! delay slot +#if defined(RTEMS_SMP) +check_is_executing: + + ! Check the is executing indicator of the heir context + ld [%o1 + SPARC_CONTEXT_CONTROL_IS_EXECUTING_OFFSET], %g1 + cmp %g1, 0 + beq try_update_is_executing + mov 1, %g1 + + ! Check if a thread dispatch is necessary + ldub [%g6 + PER_CPU_DISPATCH_NEEDED], %g1 + cmp %g1, 0 + beq check_is_executing + nop + + ! We have a new heir + + ! Clear the thread dispatch necessary flag + stub %g0, [%g6 + PER_CPU_DISPATCH_NEEDED] + + ! Here we assume a strong memory order, otherwise a memory barrier must + ! be inserted here + + ! Read the executing and heir + ld [%g6 + PER_CPU_OFFSET_EXECUTING], %g1 + ld [%g6 + PER_CPU_OFFSET_HEIR], %g2 + + ! Calculate the heir context pointer + sub %o1, %g1, %g1 + add %g1, %g2, %o1 + + ! Update the executing + st %g2, [%g6 + PER_CPU_OFFSET_EXECUTING] + + ba try_update_is_executing + mov 1, %g1 +#endif + /* * void _CPU_Context_restore( * Context_Control *new_context |