zephyr/arch/arc/core/fault_s.S

240 lines
5.3 KiB
ArmAsm

/*
* Copyright (c) 2014 Wind River Systems, Inc.
*
* SPDX-License-Identifier: Apache-2.0
*/
/**
* @file
* @brief Fault handlers for ARCv2
*
* Fault handlers for ARCv2 processors.
*/
#include <toolchain.h>
#include <linker/sections.h>
#include <arch/cpu.h>
#include <swap_macros.h>
GTEXT(_Fault)
GTEXT(__reset)
GTEXT(__memory_error)
GTEXT(__instruction_error)
GTEXT(__ev_machine_check)
GTEXT(__ev_tlb_miss_i)
GTEXT(__ev_tlb_miss_d)
GTEXT(__ev_prot_v)
GTEXT(__ev_privilege_v)
GTEXT(__ev_swi)
GTEXT(__ev_trap)
GTEXT(__ev_extension)
GTEXT(__ev_div_zero)
GTEXT(__ev_dc_error)
GTEXT(__ev_maligned)
GDATA(exc_nest_count)
/*
* @brief Fault handler installed in the fault and reserved vectors
*/
SECTION_SUBSEC_FUNC(TEXT,__fault,__memory_error)
SECTION_SUBSEC_FUNC(TEXT,__fault,__instruction_error)
SECTION_SUBSEC_FUNC(TEXT,__fault,__ev_machine_check)
SECTION_SUBSEC_FUNC(TEXT,__fault,__ev_tlb_miss_i)
SECTION_SUBSEC_FUNC(TEXT,__fault,__ev_tlb_miss_d)
SECTION_SUBSEC_FUNC(TEXT,__fault,__ev_prot_v)
SECTION_SUBSEC_FUNC(TEXT,__fault,__ev_privilege_v)
SECTION_SUBSEC_FUNC(TEXT,__fault,__ev_swi)
#if !defined(CONFIG_IRQ_OFFLOAD) && !defined(CONFIG_USERSPACE)
SECTION_SUBSEC_FUNC(TEXT,__fault,__ev_trap)
#endif
SECTION_SUBSEC_FUNC(TEXT,__fault,__ev_extension)
SECTION_SUBSEC_FUNC(TEXT,__fault,__ev_div_zero)
SECTION_SUBSEC_FUNC(TEXT,__fault,__ev_dc_error)
SECTION_SUBSEC_FUNC(TEXT,__fault,__ev_maligned)
/*
* Before invoking exception handler, the kernel switches to an exception
* stack, to save the faulting thread's registers.
* The exception is fatal and all the kernel can do is just print
* a diagnostic message and halt.
*/
#ifdef CONFIG_ARC_STACK_CHECKING
push_s r2
/* disable stack checking */
lr r2, [_ARC_V2_STATUS32]
bclr r2, r2, _ARC_V2_STATUS32_SC_BIT
kflag r2
pop_s r2
#endif
/* save caller saved registers */
_create_irq_stack_frame
lr r0,[_ARC_V2_ERSTATUS]
st_s r0, [sp, ___isf_t_status32_OFFSET]
lr r0,[_ARC_V2_ERET]
st_s r0, [sp, ___isf_t_pc_OFFSET] /* eret into pc */
#ifndef CONFIG_USERSPACE
ld r1, [exc_nest_count]
add r0, r1, 1
st r0, [exc_nest_count]
cmp r1, 0
bgt.d exc_nest_handle
mov r0, sp
mov r1, _kernel
ld sp, [r1, _kernel_offset_to_irq_stack]
exc_nest_handle:
push_s r0
#endif
jl _Fault
#ifndef CONFIG_USERSPACE
pop sp
mov r1, exc_nest_count
ld r0, [r1]
sub r0, r0, 1
st r0, [r1]
#endif
/* if _Fault returns, restore the registers */
_pop_irq_stack_frame
rtie
#ifdef CONFIG_IRQ_OFFLOAD
GTEXT(_irq_do_offload);
#endif
#if defined(CONFIG_IRQ_OFFLOAD) || defined(CONFIG_USERSPACE)
SECTION_SUBSEC_FUNC(TEXT,__fault,__ev_trap)
#ifdef CONFIG_USERSPACE
/* get the id of trap_s */
lr ilink, [_ARC_V2_ECR]
and ilink, ilink, 0x3f
cmp ilink, 0x3
bne _do_other_trap
/* do sys_call */
mov ilink, _SYSCALL_LIMIT
cmp r6, ilink
blt valid_syscall_id
mov r0, r6
mov r6, _SYSCALL_BAD
valid_syscall_id:
lr ilink, [_ARC_V2_ERET]
push ilink
lr ilink, [_ARC_V2_ERSTATUS]
push ilink
bclr ilink, ilink, _ARC_V2_STATUS32_U_BIT
sr ilink, [_ARC_V2_ERSTATUS]
mov ilink, _arc_do_syscall
sr ilink, [_ARC_V2_ERET]
rtie
/*
* Before invoking exception handler, the kernel switches to an exception
* stack to save the faulting thread's registers.
* The exception is fatal and all the kernel can do is just print
* a diagnostic message and halt.
*/
_do_other_trap:
#endif /* CONFIG_USERSPACE */
#ifdef CONFIG_ARC_STACK_CHECKING
push_s r2
/* disable stack checking */
lr r2, [_ARC_V2_STATUS32]
bclr r2, r2, _ARC_V2_STATUS32_SC_BIT
kflag r2
pop_s r2
#endif
/* save caller saved registers */
_create_irq_stack_frame
lr r0,[_ARC_V2_ERSTATUS]
st_s r0, [sp, ___isf_t_status32_OFFSET]
lr r0,[_ARC_V2_ERET]
st_s r0, [sp, ___isf_t_pc_OFFSET] /* eret into pc */
ld r1, [exc_nest_count]
add r0, r1, 1
st r0, [exc_nest_count]
cmp r1, 0
bgt.d trap_nest_handle
mov r0, sp
mov r1, _kernel
ld sp, [r1, _kernel_offset_to_irq_stack]
trap_nest_handle:
push_s r0
#ifdef CONFIG_IRQ_OFFLOAD
jl _irq_do_offload
#endif
pop sp
/* check if we're a nested interrupt: if so, let the
* interrupted interrupt handle the reschedule
*/
mov r1, exc_nest_count
ld r0, [r1]
sub r0, r0, 1
cmp r0, 0
beq.d _trap_check_for_swap
st r0, [r1]
_trap_return:
_pop_irq_stack_frame
rtie
.balign 4
_trap_check_for_swap:
mov_s r1, _kernel
ld_s r2, [r1, _kernel_offset_to_current]
/*
* Non-preemptible thread ? Do not schedule (see explanation of
* preempt field in kernel_struct.h).
*/
ldh_s r0, [r2, _thread_offset_to_preempt]
brhs r0, _NON_PREEMPT_THRESHOLD, _trap_return
/* check if the current thread needs to be rescheduled */
ld_s r0, [r1, _kernel_offset_to_ready_q_cache]
breq r0, r2, _trap_return
_save_callee_saved_regs
st _CAUSE_RIRQ, [r2, _thread_offset_to_relinquish_cause]
/* note: Ok to use _CAUSE_RIRQ since everything is saved */
ld_s r2, [r1, _kernel_offset_to_ready_q_cache]
st_s r2, [r1, _kernel_offset_to_current]
/* clear AE bit to forget this was an exception */
lr r3, [_ARC_V2_STATUS32]
and r3,r3,(~_ARC_V2_STATUS32_AE)
kflag r3
/* pretend lowest priority interrupt happened to use common handler */
lr r3, [_ARC_V2_AUX_IRQ_ACT]
or r3,r3,(1<<(CONFIG_NUM_IRQ_PRIO_LEVELS-1)) /* use lowest */
sr r3, [_ARC_V2_AUX_IRQ_ACT]
/* Assumption: r2 has current thread */
b _rirq_common_interrupt_swap
#endif /* CONFIG_IRQ_OFFLOAD || CONFIG_USERSPACE */