zephyr/arch/arc/core/fault_s.S

191 lines
4.7 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 <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)
.balign 4
SECTION_VAR(BSS, saved_stack_pointer)
.word 0
#if CONFIG_RGF_NUM_BANKS == 1
GDATA(_exception_stack)
SECTION_VAR(NOINIT, _exception_stack)
.space 512
/* note: QUARK_SE_C1000_SS can't afford 512B */
#else
GDATA(_firq_stack)
#endif
/*
* @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)
#ifndef CONFIG_IRQ_OFFLOAD
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
st sp, [saved_stack_pointer]
#if CONFIG_RGF_NUM_BANKS == 1
mov_s sp, _exception_stack
add sp, sp, 512
#else
mov_s sp, _firq_stack
add sp, sp, CONFIG_FIRQ_STACK_SIZE
#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 */
jl _Fault
/* if _Fault returns, restore the registers */
_pop_irq_stack_frame
/* now restore the stack */
ld sp,[saved_stack_pointer]
rtie
#ifdef CONFIG_IRQ_OFFLOAD
GTEXT(_irq_do_offload);
SECTION_SUBSEC_FUNC(TEXT,__fault,__ev_trap)
/*
* 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 */
jl _irq_do_offload
mov_s r1, _kernel
ld_s r2, [r1, _kernel_offset_to_current]
/* check if we're a nested interrupt: if so, let the
* interrupted interrupt handle the reschedule
*/
lr r3, [_ARC_V2_AUX_IRQ_ACT]
/* the OS on ARCv2 always runs in kernel mode, so assume bit31 [U] in
* AUX_IRQ_ACT is always 0: if the contents of AUX_IRQ_ACT is 0, it
* means trap was taken from outside an interrupt handler.
* But if it was inside, let that handler do the swap.
*/
breq r3, 0, _trap_check_for_swap
_trap_return:
_pop_irq_stack_frame
rtie
.balign 4
_trap_check_for_swap:
/*
* 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 */