sh: Kill off kgdb's magical NMI debouncing.

[safe/jmp/linux-2.6] / arch / sh / kernel / cpu / sh3 / entry.S

diff --git a/arch/sh/kernel/cpu/sh3/entry.S b/arch/sh/kernel/cpu/sh3/entry.S
index 67ad646..0151933 100644 (file)
--- a/arch/sh/kernel/cpu/sh3/entry.S
+++ b/arch/sh/kernel/cpu/sh3/entry.S
@@ -53,10 +53,6 @@
  *     syscall #
  *
  */
-#if defined(CONFIG_KGDB)
-NMI_VEC = 0x1c0                        ! Must catch early for debounce
-#endif
-
 /* Offsets to the stack */
 OFF_R0  =  0           /* Return value. New ABI also arg4 */
 OFF_R1  =  4           /* New ABI: arg5 */
@@ -71,7 +67,6 @@ OFF_PC  =  (16*4)
 OFF_SR =  (16*4+8)
 OFF_TRA        =  (16*4+6*4)
 
-
 #define k0     r0
 #define k1     r1
 #define k2     r2
@@ -113,35 +108,34 @@ OFF_TRA   =  (16*4+6*4)
 #if defined(CONFIG_MMU)
        .align  2
 ENTRY(tlb_miss_load)
-       bra     call_dpf
+       bra     call_handle_tlbmiss
         mov    #0, r5
 
        .align  2
 ENTRY(tlb_miss_store)
-       bra     call_dpf
+       bra     call_handle_tlbmiss
         mov    #1, r5
 
        .align  2
 ENTRY(initial_page_write)
-       bra     call_dpf
-        mov    #1, r5
+       bra     call_handle_tlbmiss
+        mov    #2, r5
 
        .align  2
 ENTRY(tlb_protection_violation_load)
-       bra     call_dpf
+       bra     call_do_page_fault
         mov    #0, r5
 
        .align  2
 ENTRY(tlb_protection_violation_store)
-       bra     call_dpf
+       bra     call_do_page_fault
         mov    #1, r5
 
-call_dpf:
+call_handle_tlbmiss:
        setup_frame_reg
        mov.l   1f, r0
        mov     r5, r8
        mov.l   @r0, r6
-       mov     r6, r9
        mov.l   2f, r0
        sts     pr, r10
        jsr     @r0
@@ -152,16 +146,25 @@ call_dpf:
         lds    r10, pr
        rts
         nop
-0:     mov.l   3f, r0
-       mov     r9, r6
+0:
        mov     r8, r5
+call_do_page_fault:
+       mov.l   1f, r0
+       mov.l   @r0, r6
+
+       sti
+
+       mov.l   3f, r0
+       mov.l   4f, r1
+       mov     r15, r4
        jmp     @r0
-        mov    r15, r4
+        lds    r1, pr
 
        .align 2
 1:     .long   MMU_TEA
-2:     .long   __do_page_fault
+2:     .long   handle_tlbmiss
 3:     .long   do_page_fault
+4:     .long   ret_from_exception
 
        .align  2
 ENTRY(address_error_load)
@@ -257,7 +260,7 @@ restore_all:
        !
        ! Calculate new SR value
        mov     k3, k2                  ! original SR value
-       mov     #0xf0, k1
+       mov     #0xfffffff0, k1
        extu.b  k1, k1
        not     k1, k1
        and     k1, k2                  ! Mask original SR value
@@ -273,21 +276,12 @@ restore_all:
 6:     or      k0, k2                  ! Set the IMASK-bits
        ldc     k2, ssr
        !
-#if defined(CONFIG_KGDB)
-       ! Clear in_nmi
-       mov.l   6f, k0
-       mov     #0, k1
-       mov.b   k1, @k0
-#endif
        mov     k4, r15
        rte
         nop
 
        .align  2
 5:     .long   0x00001000      ! DSP
-#ifdef CONFIG_KGDB
-6:     .long   in_nmi
-#endif
 7:     .long   0x30000000
 
 ! common exception handler
@@ -479,23 +473,6 @@ ENTRY(save_low_regs)
 !
        .balign         512,0,512
 ENTRY(handle_interrupt)
-#if defined(CONFIG_KGDB)
-       mov.l   2f, k2
-       ! Debounce (filter nested NMI)
-       mov.l   @k2, k0
-       mov.l   9f, k1
-       cmp/eq  k1, k0
-       bf      11f
-       mov.l   10f, k1
-       tas.b   @k1
-       bt      11f
-       rte
-        nop
-       .align  2
-9:     .long   NMI_VEC
-10:    .long   in_nmi
-11:
-#endif /* defined(CONFIG_KGDB) */
        sts     pr, k3          ! save original pr value in k3
        mova    exception_data, k0
 
@@ -508,13 +485,49 @@ ENTRY(handle_interrupt)
        bsr     save_regs       ! needs original pr value in k3
         mov    #-1, k2         ! default vector kept in k2
 
+       setup_frame_reg
+
+       stc     sr, r0  ! get status register
+       shlr2   r0
+       and     #0x3c, r0
+       cmp/eq  #0x3c, r0
+       bf      9f
+       TRACE_IRQS_OFF
+9:
+
        ! Setup return address and jump to do_IRQ
        mov.l   4f, r9          ! fetch return address
        lds     r9, pr          ! put return address in pr
        mov.l   2f, r4
        mov.l   3f, r9
        mov.l   @r4, r4         ! pass INTEVT vector as arg0
+
+       shlr2   r4
+       shlr    r4
+       mov     r4, r0          ! save vector->jmp table offset for later
+
+       shlr2   r4              ! vector to IRQ# conversion
+       add     #-0x10, r4
+
+       cmp/pz  r4              ! is it a valid IRQ?
+       bt      10f
+
+       /*
+        * We got here as a result of taking the INTEVT path for something
+        * that isn't a valid hard IRQ, therefore we bypass the do_IRQ()
+        * path and special case the event dispatch instead.  This is the
+        * expected path for the NMI (and any other brilliantly implemented
+        * exception), which effectively wants regular exception dispatch
+        * but is unfortunately reported through INTEVT rather than
+        * EXPEVT.  Grr.
+        */
+       mov.l   6f, r9
+       mov.l   @(r0, r9), r9
        jmp     @r9
+        mov    r15, r8         ! trap handlers take saved regs in r8
+
+10:
+       jmp     @r9             ! Off to do_IRQ() we go.
         mov    r15, r5         ! pass saved registers as arg1
 
 ENTRY(exception_none)