diff options
Diffstat (limited to 'arch/arc/include/asm/entry.h')
| -rw-r--r-- | arch/arc/include/asm/entry.h | 107 |
1 files changed, 29 insertions, 78 deletions
diff --git a/arch/arc/include/asm/entry.h b/arch/arc/include/asm/entry.h index 2980bc9b7653..49c2e090cb5c 100644 --- a/arch/arc/include/asm/entry.h +++ b/arch/arc/include/asm/entry.h @@ -91,7 +91,7 @@ * Helpers to save/restore callee-saved regs: * used by several macros below *-------------------------------------------------------------*/ -.macro SAVE_R13_TO_R24 +.macro SAVE_R13_TO_R25 PUSH r13 PUSH r14 PUSH r15 @@ -104,9 +104,11 @@ PUSH r22 PUSH r23 PUSH r24 + PUSH r25 .endm -.macro RESTORE_R24_TO_R13 +.macro RESTORE_R25_TO_R13 + POP r25 POP r24 POP r23 POP r22 @@ -121,81 +123,31 @@ POP r13 .endm -/*-------------------------------------------------------------- - * Collect User Mode callee regs as struct callee_regs - needed by - * fork/do_signal/unaligned-access-emulation. - * (By default only scratch regs are saved on entry to kernel) - * - * Special handling for r25 if used for caching Task Pointer. - * It would have been saved in task->thread.user_r25 already, but to keep - * the interface same it is copied into regular r25 placeholder in - * struct callee_regs. - *-------------------------------------------------------------*/ +/* + * save user mode callee regs as struct callee_regs + * - needed by fork/do_signal/unaligned-access-emulation. + */ .macro SAVE_CALLEE_SAVED_USER + SAVE_R13_TO_R25 +.endm - mov r12, sp ; save SP as ref to pt_regs - SAVE_R13_TO_R24 - -#ifdef CONFIG_ARC_CURR_IN_REG - ; Retrieve orig r25 and save it with rest of callee_regs - ld r12, [r12, PT_user_r25] - PUSH r12 -#else - PUSH r25 -#endif - +/* + * restore user mode callee regs as struct callee_regs + * - could have been changed by ptrace tracer or unaligned-access fixup + */ +.macro RESTORE_CALLEE_SAVED_USER + RESTORE_R25_TO_R13 .endm -/*-------------------------------------------------------------- - * Save kernel Mode callee regs at the time of Contect Switch. - * - * Special handling for r25 if used for caching Task Pointer. - * Kernel simply skips saving it since it will be loaded with - * incoming task pointer anyways - *-------------------------------------------------------------*/ +/* + * save/restore kernel mode callee regs at the time of context switch + */ .macro SAVE_CALLEE_SAVED_KERNEL - - SAVE_R13_TO_R24 - -#ifdef CONFIG_ARC_CURR_IN_REG - sub sp, sp, 4 -#else - PUSH r25 -#endif + SAVE_R13_TO_R25 .endm -/*-------------------------------------------------------------- - * Opposite of SAVE_CALLEE_SAVED_KERNEL - *-------------------------------------------------------------*/ .macro RESTORE_CALLEE_SAVED_KERNEL - -#ifdef CONFIG_ARC_CURR_IN_REG - add sp, sp, 4 /* skip usual r25 placeholder */ -#else - POP r25 -#endif - RESTORE_R24_TO_R13 -.endm - -/*-------------------------------------------------------------- - * Opposite of SAVE_CALLEE_SAVED_USER - * - * ptrace tracer or unaligned-access fixup might have changed a user mode - * callee reg which is saved back to usual r25 storage location - *-------------------------------------------------------------*/ -.macro RESTORE_CALLEE_SAVED_USER - -#ifdef CONFIG_ARC_CURR_IN_REG - POP r12 -#else - POP r25 -#endif - RESTORE_R24_TO_R13 - - ; SP is back to start of pt_regs -#ifdef CONFIG_ARC_CURR_IN_REG - st r12, [sp, PT_user_r25] -#endif + RESTORE_R25_TO_R13 .endm /*-------------------------------------------------------------- @@ -231,10 +183,10 @@ #ifdef CONFIG_SMP -/*------------------------------------------------- +/* * Retrieve the current running task on this CPU - * 1. Determine curr CPU id. - * 2. Use it to index into _current_task[ ] + * - loads it from backing _current_task[] (and can't use the + * caching reg for current task */ .macro GET_CURR_TASK_ON_CPU reg GET_CPU_ID \reg @@ -256,7 +208,7 @@ add2 \tmp, @_current_task, \tmp st \tsk, [\tmp] #ifdef CONFIG_ARC_CURR_IN_REG - mov r25, \tsk + mov gp, \tsk #endif .endm @@ -271,21 +223,20 @@ .macro SET_CURR_TASK_ON_CPU tsk, tmp st \tsk, [@_current_task] #ifdef CONFIG_ARC_CURR_IN_REG - mov r25, \tsk + mov gp, \tsk #endif .endm #endif /* SMP / UNI */ -/* ------------------------------------------------------------------ +/* * Get the ptr to some field of Current Task at @off in task struct - * -Uses r25 for Current task ptr if that is enabled + * - Uses current task cached in reg if enabled */ - #ifdef CONFIG_ARC_CURR_IN_REG .macro GET_CURR_TASK_FIELD_PTR off, reg - add \reg, r25, \off + add \reg, gp, \off .endm #else |