Merge tag 'xtensa-next-20130508' of git://github.com/czankel/xtensa-linux

[karo-tx-linux.git] / arch / xtensa / kernel / entry.S

diff --git a/arch/xtensa/kernel/entry.S b/arch/xtensa/kernel/entry.S
index 63845f950792ce86f3acfa2f4d93d858171d8d0f..5082507d5631b3e6bf865ab82d40bb1975bffc3a 100644 (file)
--- a/arch/xtensa/kernel/entry.S
+++ b/arch/xtensa/kernel/entry.S
@@ -354,16 +354,16 @@ common_exception:
         * so we can allow exceptions and interrupts (*) again.
         * Set PS(EXCM = 0, UM = 0, RING = 0, OWB = 0, WOE = 1, INTLEVEL = X)
         *
-        * (*) We only allow interrupts of higher priority than current IRQ
+        * (*) We only allow interrupts if they were previously enabled and
+        *     we're not handling an IRQ
         */
 
        rsr     a3, ps
-       addi    a0, a0, -4
-       movi    a2, 1
+       addi    a0, a0, -EXCCAUSE_LEVEL1_INTERRUPT
+       movi    a2, LOCKLEVEL
        extui   a3, a3, PS_INTLEVEL_SHIFT, PS_INTLEVEL_WIDTH
                                        # a3 = PS.INTLEVEL
-       movnez  a2, a3, a3              # a2 = 1: level-1, > 1: high priority
-       moveqz  a3, a2, a0              # a3 = IRQ level iff interrupt
+       moveqz  a3, a2, a0              # a3 = LOCKLEVEL iff interrupt
        movi    a2, 1 << PS_WOE_BIT
        or      a3, a3, a2
        rsr     a0, exccause
@@ -389,6 +389,22 @@ common_exception:
 
        save_xtregs_opt a1 a2 a4 a5 a6 a7 PT_XTREGS_OPT
        
+#ifdef CONFIG_TRACE_IRQFLAGS
+       l32i    a4, a1, PT_DEPC
+       /* Double exception means we came here with an exception
+        * while PS.EXCM was set, i.e. interrupts disabled.
+        */
+       bgeui   a4, VALID_DOUBLE_EXCEPTION_ADDRESS, 1f
+       l32i    a4, a1, PT_EXCCAUSE
+       bnei    a4, EXCCAUSE_LEVEL1_INTERRUPT, 1f
+       /* We came here with an interrupt means interrupts were enabled
+        * and we've just disabled them.
+        */
+       movi    a4, trace_hardirqs_off
+       callx4  a4
+1:
+#endif
+
        /* Go to second-level dispatcher. Set up parameters to pass to the
         * exception handler and call the exception handler.
         */
@@ -407,11 +423,29 @@ common_exception:
        .global common_exception_return
 common_exception_return:
 
+#ifdef CONFIG_TRACE_IRQFLAGS
+       l32i    a4, a1, PT_DEPC
+       /* Double exception means we came here with an exception
+        * while PS.EXCM was set, i.e. interrupts disabled.
+        */
+       bgeui   a4, VALID_DOUBLE_EXCEPTION_ADDRESS, 1f
+       l32i    a4, a1, PT_EXCCAUSE
+       bnei    a4, EXCCAUSE_LEVEL1_INTERRUPT, 1f
+       /* We came here with an interrupt means interrupts were enabled
+        * and we'll reenable them on return.
+        */
+       movi    a4, trace_hardirqs_on
+       callx4  a4
+1:
+#endif
+
        /* Jump if we are returning from kernel exceptions. */
 
 1:     l32i    a3, a1, PT_PS
        _bbci.l a3, PS_UM_BIT, 4f
 
+       rsil    a2, 0
+
        /* Specific to a user exception exit:
         * We need to check some flags for signal handling and rescheduling,
         * and have to restore WB and WS, extra states, and all registers
@@ -652,51 +686,19 @@ common_exception_exit:
 
        l32i    a0, a1, PT_DEPC
        l32i    a3, a1, PT_AREG3
-       _bltui  a0, VALID_DOUBLE_EXCEPTION_ADDRESS, 1f
-
-       wsr     a0, depc
        l32i    a2, a1, PT_AREG2
-       l32i    a0, a1, PT_AREG0
-       l32i    a1, a1, PT_AREG1
-       rfde
+       _bgeui  a0, VALID_DOUBLE_EXCEPTION_ADDRESS, 1f
 
-1:
        /* Restore a0...a3 and return */
 
-       rsr     a0, ps
-       extui   a2, a0, PS_INTLEVEL_SHIFT, PS_INTLEVEL_WIDTH
-       movi    a0, 2f
-       slli    a2, a2, 4
-       add     a0, a2, a0
-       l32i    a2, a1, PT_AREG2
-       jx      a0
-
-       .macro  irq_exit_level level
-       .align  16
-       .if     XCHAL_EXCM_LEVEL >= \level
-       l32i    a0, a1, PT_PC
-       wsr     a0, epc\level
        l32i    a0, a1, PT_AREG0
        l32i    a1, a1, PT_AREG1
-       rfi     \level
-       .endif
-       .endm
+       rfe
 
-       .align  16
-2:
+1:     wsr     a0, depc
        l32i    a0, a1, PT_AREG0
        l32i    a1, a1, PT_AREG1
-       rfe
-
-       .align  16
-       /* no rfi for level-1 irq, handled by rfe above*/
-       nop
-
-       irq_exit_level 2
-       irq_exit_level 3
-       irq_exit_level 4
-       irq_exit_level 5
-       irq_exit_level 6
+       rfde
 
 ENDPROC(kernel_exception)