diff options
Diffstat (limited to 'arch/sh/kernel/entry.S')
| -rw-r--r-- | arch/sh/kernel/entry.S | 43 |
1 files changed, 33 insertions, 10 deletions
diff --git a/arch/sh/kernel/entry.S b/arch/sh/kernel/entry.S index 97c571fbcdf..39aaefb2d83 100644 --- a/arch/sh/kernel/entry.S +++ b/arch/sh/kernel/entry.S @@ -1,9 +1,8 @@ -/* $Id: entry.S,v 1.37 2004/06/11 13:02:46 doyu Exp $ - * +/* * linux/arch/sh/entry.S * * Copyright (C) 1999, 2000, 2002 Niibe Yutaka - * Copyright (C) 2003 Paul Mundt + * Copyright (C) 2003 - 2006 Paul Mundt * * This file is subject to the terms and conditions of the GNU General Public * License. See the file "COPYING" in the main directory of this archive @@ -78,7 +77,6 @@ OFF_TRA = (16*4+6*4) #define k3 r3 #define k4 r4 -#define k_ex_code r2_bank /* r2_bank1 */ #define g_imask r6 /* r6_bank1 */ #define k_g_imask r6_bank /* r6_bank1 */ #define current r7 /* r7_bank1 */ @@ -691,7 +689,7 @@ interrupt: 0: #endif /* defined(CONFIG_KGDB_NMI) */ bra handle_exception - mov.l @k2, k2 + mov #-1, k2 ! interrupt exception marker .align 2 1: .long EXPEVT @@ -717,8 +715,7 @@ ENTRY(handle_exception) add current, k1 mov k1, r15 ! change to kernel stack ! -1: mov #-1, k4 - mov.l 2f, k1 +1: mov.l 2f, k1 ! #ifdef CONFIG_SH_DSP mov.l r2, @-r15 ! Save r2, we need another reg @@ -763,6 +760,8 @@ skip_save: #endif ! Save the user registers on the stack. mov.l k2, @-r15 ! EXPEVT + + mov #-1, k4 mov.l k4, @-r15 ! set TRA (default: -1) ! sts.l macl, @-r15 @@ -797,8 +796,21 @@ skip_save: mov.l r2, @-r15 mov.l r1, @-r15 mov.l r0, @-r15 - ! Then, dispatch to the handler, according to the exception code. - stc k_ex_code, r8 + + /* + * This gets a bit tricky.. in the INTEVT case we don't want to use + * the VBR offset as a destination in the jump call table, since all + * of the destinations are the same. In this case, (interrupt) sets + * a marker in r2 (now r2_bank since SR.RB changed), which we check + * to determine the exception type. For all other exceptions, we + * forcibly read EXPEVT from memory and fix up the jump address, in + * the interrupt exception case we jump to do_IRQ() and defer the + * INTEVT read until there. As a bonus, we can also clean up the SR.RB + * checks that do_IRQ() was doing.. + */ + stc r2_bank, r8 + cmp/pz r8 + bf interrupt_exception shlr2 r8 shlr r8 mov.l 4f, r9 @@ -806,6 +818,8 @@ skip_save: mov.l @r9, r9 jmp @r9 nop + rts + nop .align 2 1: .long 0x00001000 ! DSP=1 @@ -813,8 +827,17 @@ skip_save: 3: .long 0xcfffffff ! RB=0, BL=0 4: .long exception_handling_table +interrupt_exception: + mov.l 1f, r9 + jmp @r9 + nop + rts + nop + + .align 2 +1: .long do_IRQ + .align 2 ENTRY(exception_none) rts nop - |