diff options
Diffstat (limited to 'arch/mn10300/kernel/switch_to.S')
| -rw-r--r-- | arch/mn10300/kernel/switch_to.S | 118 |
1 files changed, 113 insertions, 5 deletions
diff --git a/arch/mn10300/kernel/switch_to.S b/arch/mn10300/kernel/switch_to.S index 630aad71b94..de3e74fc9ea 100644 --- a/arch/mn10300/kernel/switch_to.S +++ b/arch/mn10300/kernel/switch_to.S @@ -15,6 +15,9 @@ #include <linux/linkage.h> #include <asm/thread_info.h> #include <asm/cpu-regs.h> +#ifdef CONFIG_SMP +#include <proc/smp-regs.h> +#endif /* CONFIG_SMP */ .text @@ -35,14 +38,18 @@ ENTRY(__switch_to) mov d1,a1 # save prev context - mov (__frame),d0 - mov d0,(THREAD_FRAME,a0) mov __switch_back,d0 - mov d0,(THREAD_PC,a0) mov sp,a2 mov a2,(THREAD_SP,a0) mov a3,(THREAD_A3,a0) +#ifdef CONFIG_KGDB + btst 0xff,(kgdb_single_step) + bne __switch_to__lift_sstep_bp +__switch_to__continue: +#endif + mov d0,(THREAD_PC,a0) + mov (THREAD_A3,a1),a3 mov (THREAD_SP,a1),a2 @@ -58,8 +65,6 @@ ENTRY(__switch_to) mov a2,e2 #endif - mov (THREAD_FRAME,a1),a2 - mov a2,(__frame) mov (THREAD_PC,a1),a2 mov d2,d0 # for ret_from_fork mov d0,a0 # for __switch_to @@ -69,3 +74,106 @@ ENTRY(__switch_to) __switch_back: and ~EPSW_NMID,epsw ret [d2,d3,a2,a3,exreg1],32 + +#ifdef CONFIG_KGDB +############################################################################### +# +# Lift the single-step breakpoints when the task being traced is switched out +# A0 = prev +# A1 = next +# +############################################################################### +__switch_to__lift_sstep_bp: + add -12,sp + mov a0,e4 + mov a1,e5 + + # Clear the single-step flag to prevent us coming this way until we get + # switched back in + bclr 0xff,(kgdb_single_step) + + # Remove first breakpoint + mov (kgdb_sstep_bp_addr),a2 + cmp 0,a2 + beq 1f + movbu (kgdb_sstep_bp),d0 + movbu d0,(a2) +#if defined(CONFIG_MN10300_CACHE_FLUSH_ICACHE) || defined(CONFIG_MN10300_CACHE_INV_ICACHE) + mov a2,d0 + mov a2,d1 + add 1,d1 + calls flush_icache_range +#endif +1: + + # Remove second breakpoint + mov (kgdb_sstep_bp_addr+4),a2 + cmp 0,a2 + beq 2f + movbu (kgdb_sstep_bp+1),d0 + movbu d0,(a2) +#if defined(CONFIG_MN10300_CACHE_FLUSH_ICACHE) || defined(CONFIG_MN10300_CACHE_INV_ICACHE) + mov a2,d0 + mov a2,d1 + add 1,d1 + calls flush_icache_range +#endif +2: + + # Change the resumption address and return + mov __switch_back__reinstall_sstep_bp,d0 + mov e4,a0 + mov e5,a1 + add 12,sp + bra __switch_to__continue + +############################################################################### +# +# Reinstall the single-step breakpoints when the task being traced is switched +# back in (A1 points to the new thread_struct). +# +############################################################################### +__switch_back__reinstall_sstep_bp: + add -12,sp + mov a0,e4 # save the return value + mov 0xff,d3 + + # Reinstall first breakpoint + mov (kgdb_sstep_bp_addr),a2 + cmp 0,a2 + beq 1f + movbu (a2),d0 + movbu d0,(kgdb_sstep_bp) + movbu d3,(a2) +#if defined(CONFIG_MN10300_CACHE_FLUSH_ICACHE) || defined(CONFIG_MN10300_CACHE_INV_ICACHE) + mov a2,d0 + mov a2,d1 + add 1,d1 + calls flush_icache_range +#endif +1: + + # Reinstall second breakpoint + mov (kgdb_sstep_bp_addr+4),a2 + cmp 0,a2 + beq 2f + movbu (a2),d0 + movbu d0,(kgdb_sstep_bp+1) + movbu d3,(a2) +#if defined(CONFIG_MN10300_CACHE_FLUSH_ICACHE) || defined(CONFIG_MN10300_CACHE_INV_ICACHE) + mov a2,d0 + mov a2,d1 + add 1,d1 + calls flush_icache_range +#endif +2: + + mov d3,(kgdb_single_step) + + # Restore the return value (the previous thread_struct pointer) + mov e4,a0 + mov a0,d0 + add 12,sp + bra __switch_back + +#endif /* CONFIG_KGDB */ |