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Diffstat (limited to 'arch/arc/include/asm/entry.h')
| -rw-r--r-- | arch/arc/include/asm/entry.h | 298 |
1 files changed, 298 insertions, 0 deletions
diff --git a/arch/arc/include/asm/entry.h b/arch/arc/include/asm/entry.h new file mode 100644 index 000000000..fcdd59d77 --- /dev/null +++ b/arch/arc/include/asm/entry.h @@ -0,0 +1,298 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright (C) 2014-15 Synopsys, Inc. (www.synopsys.com) + * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) + */ + +#ifndef __ASM_ARC_ENTRY_H +#define __ASM_ARC_ENTRY_H + +#include <asm/unistd.h> /* For NR_syscalls defination */ +#include <asm/arcregs.h> +#include <asm/ptrace.h> +#include <asm/processor.h> /* For VMALLOC_START */ +#include <asm/mmu.h> + +#ifdef CONFIG_ISA_ARCOMPACT +#include <asm/entry-compact.h> /* ISA specific bits */ +#else +#include <asm/entry-arcv2.h> +#endif + +/* Note on the LD/ST addr modes with addr reg wback + * + * LD.a same as LD.aw + * + * LD.a reg1, [reg2, x] => Pre Incr + * Eff Addr for load = [reg2 + x] + * + * LD.ab reg1, [reg2, x] => Post Incr + * Eff Addr for load = [reg2] + */ + +.macro PUSH reg + st.a \reg, [sp, -4] +.endm + +.macro PUSHAX aux + lr r9, [\aux] + PUSH r9 +.endm + +.macro POP reg + ld.ab \reg, [sp, 4] +.endm + +.macro POPAX aux + POP r9 + sr r9, [\aux] +.endm + +/*-------------------------------------------------------------- + * Helpers to save/restore Scratch Regs: + * used by Interrupt/Exception Prologue/Epilogue + *-------------------------------------------------------------*/ +.macro SAVE_R0_TO_R12 + PUSH r0 + PUSH r1 + PUSH r2 + PUSH r3 + PUSH r4 + PUSH r5 + PUSH r6 + PUSH r7 + PUSH r8 + PUSH r9 + PUSH r10 + PUSH r11 + PUSH r12 +.endm + +.macro RESTORE_R12_TO_R0 + POP r12 + POP r11 + POP r10 + POP r9 + POP r8 + POP r7 + POP r6 + POP r5 + POP r4 + POP r3 + POP r2 + POP r1 + POP r0 + +.endm + +/*-------------------------------------------------------------- + * Helpers to save/restore callee-saved regs: + * used by several macros below + *-------------------------------------------------------------*/ +.macro SAVE_R13_TO_R24 + PUSH r13 + PUSH r14 + PUSH r15 + PUSH r16 + PUSH r17 + PUSH r18 + PUSH r19 + PUSH r20 + PUSH r21 + PUSH r22 + PUSH r23 + PUSH r24 +.endm + +.macro RESTORE_R24_TO_R13 + POP r24 + POP r23 + POP r22 + POP r21 + POP r20 + POP r19 + POP r18 + POP r17 + POP r16 + POP r15 + POP r14 + 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. + *-------------------------------------------------------------*/ +.macro SAVE_CALLEE_SAVED_USER + + 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 + +.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 + *-------------------------------------------------------------*/ +.macro SAVE_CALLEE_SAVED_KERNEL + + SAVE_R13_TO_R24 + +#ifdef CONFIG_ARC_CURR_IN_REG + sub sp, sp, 4 +#else + PUSH r25 +#endif +.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 +.endm + +/*-------------------------------------------------------------- + * Super FAST Restore callee saved regs by simply re-adjusting SP + *-------------------------------------------------------------*/ +.macro DISCARD_CALLEE_SAVED_USER + add sp, sp, SZ_CALLEE_REGS +.endm + +/*------------------------------------------------------------- + * given a tsk struct, get to the base of it's kernel mode stack + * tsk->thread_info is really a PAGE, whose bottom hoists stack + * which grows upwards towards thread_info + *------------------------------------------------------------*/ + +.macro GET_TSK_STACK_BASE tsk, out + + /* Get task->thread_info (this is essentially start of a PAGE) */ + ld \out, [\tsk, TASK_THREAD_INFO] + + /* Go to end of page where stack begins (grows upwards) */ + add2 \out, \out, (THREAD_SIZE)/4 + +.endm + +/* + * @reg [OUT] thread_info->flags of "current" + */ +.macro GET_CURR_THR_INFO_FLAGS reg + GET_CURR_THR_INFO_FROM_SP \reg + ld \reg, [\reg, THREAD_INFO_FLAGS] +.endm + +#ifdef CONFIG_SMP + +/*------------------------------------------------- + * Retrieve the current running task on this CPU + * 1. Determine curr CPU id. + * 2. Use it to index into _current_task[ ] + */ +.macro GET_CURR_TASK_ON_CPU reg + GET_CPU_ID \reg + ld.as \reg, [@_current_task, \reg] +.endm + +/*------------------------------------------------- + * Save a new task as the "current" task on this CPU + * 1. Determine curr CPU id. + * 2. Use it to index into _current_task[ ] + * + * Coded differently than GET_CURR_TASK_ON_CPU (which uses LD.AS) + * because ST r0, [r1, offset] can ONLY have s9 @offset + * while LD can take s9 (4 byte insn) or LIMM (8 byte insn) + */ + +.macro SET_CURR_TASK_ON_CPU tsk, tmp + GET_CPU_ID \tmp + add2 \tmp, @_current_task, \tmp + st \tsk, [\tmp] +#ifdef CONFIG_ARC_CURR_IN_REG + mov r25, \tsk +#endif + +.endm + + +#else /* Uniprocessor implementation of macros */ + +.macro GET_CURR_TASK_ON_CPU reg + ld \reg, [@_current_task] +.endm + +.macro SET_CURR_TASK_ON_CPU tsk, tmp + st \tsk, [@_current_task] +#ifdef CONFIG_ARC_CURR_IN_REG + mov r25, \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 + */ + +#ifdef CONFIG_ARC_CURR_IN_REG + +.macro GET_CURR_TASK_FIELD_PTR off, reg + add \reg, r25, \off +.endm + +#else + +.macro GET_CURR_TASK_FIELD_PTR off, reg + GET_CURR_TASK_ON_CPU \reg + add \reg, \reg, \off +.endm + +#endif /* CONFIG_ARC_CURR_IN_REG */ + +#endif /* __ASM_ARC_ENTRY_H */ |