diff options
Diffstat (limited to 'arch/arc/kernel/entry.S')
| -rw-r--r-- | arch/arc/kernel/entry.S | 21 |
1 files changed, 12 insertions, 9 deletions
diff --git a/arch/arc/kernel/entry.S b/arch/arc/kernel/entry.S index fd5f9160bbd2..fb0fe3265637 100644 --- a/arch/arc/kernel/entry.S +++ b/arch/arc/kernel/entry.S @@ -142,7 +142,7 @@ VECTOR reserved ; Reserved Exceptions .endr #include <linux/linkage.h> /* ARC_{EXTRY,EXIT} */ -#include <asm/entry.h> /* SAVE_ALL_{INT1,INT2,TRAP...} */ +#include <asm/entry.h> /* SAVE_ALL_{INT1,INT2,SYS...} */ #include <asm/errno.h> #include <asm/arcregs.h> #include <asm/irqflags.h> @@ -495,8 +495,6 @@ tracesys_exit: trap_with_param: ; stop_pc info by gdb needs this info - stw orig_r8_IS_BRKPT, [sp, PT_orig_r8] - mov r0, r12 lr r1, [efa] mov r2, sp @@ -541,7 +539,7 @@ ARC_ENTRY EV_Trap lr r9, [erstatus] SWITCH_TO_KERNEL_STK - SAVE_ALL_TRAP + SAVE_ALL_SYS ;------- (4) What caused the Trap -------------- lr r12, [ecr] @@ -696,28 +694,33 @@ not_exception: #ifdef CONFIG_ARC_COMPACT_IRQ_LEVELS + ; Level 2 interrupt return Path - from hardware standpoint bbit0 r10, STATUS_A2_BIT, not_level2_interrupt ;------------------------------------------------------------------ + ; However the context returning might not have taken L2 intr itself + ; e.g. Task'A' user-code -> L2 intr -> schedule -> 'B' user-code ret + ; Special considerations needed for the context which took L2 intr + + ld r9, [sp, PT_event] ; Ensure this is L2 intr context + brne r9, event_IRQ2, 149f + + ;------------------------------------------------------------------ ; if L2 IRQ interrupted a L1 ISR, we'd disbaled preemption earlier ; so that sched doesnt move to new task, causing L1 to be delayed ; undeterministically. Now that we've achieved that, lets reset ; things to what they were, before returning from L2 context ;---------------------------------------------------------------- - ldw r9, [sp, PT_orig_r8] ; get orig_r8 to make sure it is - brne r9, orig_r8_IS_IRQ2, 149f ; infact a L2 ISR ret path - ld r9, [sp, PT_status32] ; get statu32_l2 (saved in pt_regs) bbit0 r9, STATUS_A1_BIT, 149f ; L1 not active when L2 IRQ, so normal - ; A1 is set in status32_l2 ; decrement thread_info->preempt_count (re-enable preemption) GET_CURR_THR_INFO_FROM_SP r10 ld r9, [r10, THREAD_INFO_PREEMPT_COUNT] ; paranoid check, given A1 was active when A2 happened, preempt count - ; must not be 0 beccause we would have incremented it. + ; must not be 0 because we would have incremented it. ; If this does happen we simply HALT as it means a BUG !!! cmp r9, 0 bnz 2f |