Files
linux/arch/arc/include/asm/entry.h
Vineet Gupta 9de7fc30f2 ARC: entry: SAVE_ABI_CALLEE_REG: ISA/ABI specific helper
And for ARcompact variant replace the PUSH/POP macros with gas provided
push/pop pseudo-instructions

This allows ISA specific implementation

e.g. Current ARCv2 PUSH/POP could be replaced with STD/LDL to save 2
registers at a time (w/o bothering with SP update each time) or
perhaps use ENTER_S/LEAVE_S to reduce code size

For ARCv3 ABI changed so callee regs are now r14-r26 (vs. r13-r25)
thus would need a different implementation.

Signed-off-by: Vineet Gupta <vgupta@kernel.org>
2023-12-08 16:30:24 -08:00

235 lines
5.3 KiB
C

/* 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 __ASSEMBLY__
#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
/*
* save user mode callee regs as struct callee_regs
* - needed by fork/do_signal/unaligned-access-emulation.
*/
.macro SAVE_CALLEE_SAVED_USER
SAVE_ABI_CALLEE_REGS
.endm
/*
* 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_ABI_CALLEE_REGS
.endm
/*
* save/restore kernel mode callee regs at the time of context switch
*/
.macro SAVE_CALLEE_SAVED_KERNEL
SAVE_ABI_CALLEE_REGS
.endm
.macro RESTORE_CALLEE_SAVED_KERNEL
RESTORE_ABI_CALLEE_REGS
.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
* - 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
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 gp, \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 gp, \tsk
#endif
.endm
#endif /* SMP / UNI */
/*
* Get the ptr to some field of Current Task at @off in task struct
* - Uses current task cached in reg if enabled
*/
#ifdef CONFIG_ARC_CURR_IN_REG
.macro GET_CURR_TASK_FIELD_PTR off, reg
add \reg, gp, \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 */
#else /* !__ASSEMBLY__ */
extern void do_signal(struct pt_regs *);
extern void do_notify_resume(struct pt_regs *);
extern int do_privilege_fault(unsigned long, struct pt_regs *);
extern int do_extension_fault(unsigned long, struct pt_regs *);
extern int insterror_is_error(unsigned long, struct pt_regs *);
extern int do_memory_error(unsigned long, struct pt_regs *);
extern int trap_is_brkpt(unsigned long, struct pt_regs *);
extern int do_misaligned_error(unsigned long, struct pt_regs *);
extern int do_trap5_error(unsigned long, struct pt_regs *);
extern int do_misaligned_access(unsigned long, struct pt_regs *, struct callee_regs *);
extern void do_machine_check_fault(unsigned long, struct pt_regs *);
extern void do_non_swi_trap(unsigned long, struct pt_regs *);
extern void do_insterror_or_kprobe(unsigned long, struct pt_regs *);
extern void do_page_fault(unsigned long, struct pt_regs *);
#endif
#endif /* __ASM_ARC_ENTRY_H */