/*
 * Copyright (c) 2006-2018, RT-Thread Development Team
 *
 * SPDX-License-Identifier: Apache-2.0
 *
 * Change Logs:
 * Date           Author       Notes
 * 2013-07-20     Bernard      first version
 */

#include <rtthread.h>
#include <rthw.h>
#include <board.h>

#include <armv8.h>
#include "interrupt.h"
#include "mm_aspace.h"

#define DBG_TAG "libcpu.trap"
#define DBG_LVL DBG_LOG
#include <rtdbg.h>

#ifdef RT_USING_FINSH
extern long list_thread(void);
#endif

#ifdef RT_USING_LWP
#include <lwp.h>
#include <lwp_arch.h>

#ifdef LWP_USING_CORE_DUMP
#include <lwp_core_dump.h>
#endif

static void _check_fault(struct rt_hw_exp_stack *regs, uint32_t pc_adj, char *info)
{
    uint32_t is_user_fault;
    rt_thread_t th;

    is_user_fault = !(regs->cpsr & 0x1f);
    if (is_user_fault)
    {
        rt_kprintf("%s! pc = 0x%x\n", info, regs->pc - pc_adj);
    }

    /* user stack backtrace */
    th = rt_thread_self();
    if (th && th->lwp)
    {
        arch_backtrace_uthread(th);
    }

    if (is_user_fault)
    {
#ifdef LWP_USING_CORE_DUMP
        lwp_core_dump(regs, pc_adj);
#endif
        sys_exit_group(-1);
    }
}

rt_inline int _get_type(unsigned long esr)
{
    int ret;
    int fsc = ARM64_ESR_EXTRACT_FSC(esr);
    switch (fsc)
    {
        case ARM64_FSC_TRANSLATION_FAULT_LEVEL_0:
        case ARM64_FSC_TRANSLATION_FAULT_LEVEL_1:
        case ARM64_FSC_TRANSLATION_FAULT_LEVEL_2:
        case ARM64_FSC_TRANSLATION_FAULT_LEVEL_3:
            ret = MM_FAULT_TYPE_PAGE_FAULT;
            break;
        case ARM64_FSC_PERMISSION_FAULT_LEVEL_0:
        case ARM64_FSC_PERMISSION_FAULT_LEVEL_1:
        case ARM64_FSC_PERMISSION_FAULT_LEVEL_2:
        case ARM64_FSC_PERMISSION_FAULT_LEVEL_3:
            ret = MM_FAULT_TYPE_RWX_PERM;
            break;
        case ARM64_FSC_ACCESS_FLAG_FAULT_LEVEL_0:
        case ARM64_FSC_ACCESS_FLAG_FAULT_LEVEL_1:
        case ARM64_FSC_ACCESS_FLAG_FAULT_LEVEL_2:
        case ARM64_FSC_ACCESS_FLAG_FAULT_LEVEL_3:
            /* access flag fault, not handle currently */
        default:
            ret = MM_FAULT_TYPE_GENERIC;
    }
    return ret;
}

rt_inline long _irq_is_disable(long cpsr)
{
    return !!(cpsr & 0x80);
}

static int user_fault_fixable(unsigned long esr, struct rt_hw_exp_stack *regs)
{
    rt_ubase_t level;
    enum rt_mm_fault_op fault_op;
    enum rt_mm_fault_type fault_type;
    struct rt_lwp *lwp;
    void *dfar;
    int ret = 0;
    unsigned char ec = ARM64_ESR_EXTRACT_EC(esr);
    rt_bool_t is_write = ARM64_ABORT_WNR(esr);

    switch (ec)
    {
    case ARM64_EC_INST_ABORT_FROM_LO_EXCEPTION:
        fault_op = MM_FAULT_OP_EXECUTE;
        fault_type = _get_type(esr);
        break;
    case ARM64_EC_INST_ABORT_WITHOUT_A_CHANGE:
    case ARM64_EC_DATA_ABORT_FROM_LO_EXCEPTION:
    case ARM64_EC_DATA_ABORT_WITHOUT_A_CHANGE:
        fault_op = is_write ? MM_FAULT_OP_WRITE : MM_FAULT_OP_READ;
        fault_type = _get_type(esr);
        break;
    default:
        /* non-fixable */
        fault_op = 0;
        break;
    }

    /* page fault exception only allow from user space */
    lwp = lwp_self();
    if (lwp && fault_op)
    {
        __asm__ volatile("mrs %0, far_el1":"=r"(dfar));
        struct rt_aspace_fault_msg msg = {
            .fault_op = fault_op,
            .fault_type = fault_type,
            .fault_vaddr = dfar,
        };

        lwp_user_setting_save(rt_thread_self());
        __asm__ volatile("mrs %0, daif\nmsr daifclr, 0x3\nisb\n":"=r"(level));
        if (rt_aspace_fault_try_fix(lwp->aspace, &msg))
        {
            ret = 1;
        }
        __asm__ volatile("msr daif, %0\nisb\n"::"r"(level));
    }
    return ret;
}
#endif

/**
 * this function will show registers of CPU
 *
 * @param regs the registers point
 */
void rt_hw_show_register(struct rt_hw_exp_stack *regs)
{
    rt_kprintf("Execption:\n");
    rt_kprintf("X00:0x%16.16p X01:0x%16.16p X02:0x%16.16p X03:0x%16.16p\n", (void *)regs->x0, (void *)regs->x1, (void *)regs->x2, (void *)regs->x3);
    rt_kprintf("X04:0x%16.16p X05:0x%16.16p X06:0x%16.16p X07:0x%16.16p\n", (void *)regs->x4, (void *)regs->x5, (void *)regs->x6, (void *)regs->x7);
    rt_kprintf("X08:0x%16.16p X09:0x%16.16p X10:0x%16.16p X11:0x%16.16p\n", (void *)regs->x8, (void *)regs->x9, (void *)regs->x10, (void *)regs->x11);
    rt_kprintf("X12:0x%16.16p X13:0x%16.16p X14:0x%16.16p X15:0x%16.16p\n", (void *)regs->x12, (void *)regs->x13, (void *)regs->x14, (void *)regs->x15);
    rt_kprintf("X16:0x%16.16p X17:0x%16.16p X18:0x%16.16p X19:0x%16.16p\n", (void *)regs->x16, (void *)regs->x17, (void *)regs->x18, (void *)regs->x19);
    rt_kprintf("X20:0x%16.16p X21:0x%16.16p X22:0x%16.16p X23:0x%16.16p\n", (void *)regs->x20, (void *)regs->x21, (void *)regs->x22, (void *)regs->x23);
    rt_kprintf("X24:0x%16.16p X25:0x%16.16p X26:0x%16.16p X27:0x%16.16p\n", (void *)regs->x24, (void *)regs->x25, (void *)regs->x26, (void *)regs->x27);
    rt_kprintf("X28:0x%16.16p X29:0x%16.16p X30:0x%16.16p\n", (void *)regs->x28, (void *)regs->x29, (void *)regs->x30);
    rt_kprintf("SP_EL0:0x%16.16p\n", (void *)regs->sp_el0);
    rt_kprintf("SPSR  :0x%16.16p\n", (void *)regs->cpsr);
    rt_kprintf("EPC   :0x%16.16p\n", (void *)regs->pc);
}

#ifndef RT_USING_PIC
static void _rt_hw_trap_irq(rt_interrupt_context_t irq_context)
{
#ifdef SOC_BCM283x
    extern rt_uint8_t core_timer_flag;
    void *param;
    uint32_t irq;
    rt_isr_handler_t isr_func;
    extern struct rt_irq_desc isr_table[];
    uint32_t value = 0;
    value = IRQ_PEND_BASIC & 0x3ff;

    if(core_timer_flag != 0)
    {
        uint32_t cpu_id = rt_hw_cpu_id();
        uint32_t int_source = CORE_IRQSOURCE(cpu_id);
        if (int_source & 0x0f)
        {
            if (int_source & 0x08)
            {
                isr_func = isr_table[IRQ_ARM_TIMER].handler;
#ifdef RT_USING_INTERRUPT_INFO
                isr_table[IRQ_ARM_TIMER].counter++;
#endif
                if (isr_func)
                {
                    param = isr_table[IRQ_ARM_TIMER].param;
                    isr_func(IRQ_ARM_TIMER, param);
                }
            }
        }
    }

    /* local interrupt*/
    if (value)
    {
        if (value & (1 << 8))
        {
            value = IRQ_PEND1;
            irq = __rt_ffs(value) - 1;
        }
        else if (value & (1 << 9))
        {
            value = IRQ_PEND2;
            irq = __rt_ffs(value) + 31;
        }
        else
        {
            value &= 0x0f;
            irq = __rt_ffs(value) + 63;
        }

        /* get interrupt service routine */
        isr_func = isr_table[irq].handler;
#ifdef RT_USING_INTERRUPT_INFO
        isr_table[irq].counter++;
#endif
        if (isr_func)
        {
            /* Interrupt for myself. */
            param = isr_table[irq].param;
            /* turn to interrupt service routine */
            isr_func(irq, param);
        }
    }
#else
    void *param;
    int ir, ir_self;
    rt_isr_handler_t isr_func;
    extern struct rt_irq_desc isr_table[];

    ir = rt_hw_interrupt_get_irq();

    if (ir == 1023)
    {
        /* Spurious interrupt */
        return;
    }

    /* bit 10~12 is cpuid, bit 0~9 is interrupt id */
    ir_self = ir & 0x3ffUL;

    /* get interrupt service routine */
    isr_func = isr_table[ir_self].handler;
#ifdef RT_USING_INTERRUPT_INFO
    isr_table[ir_self].counter++;
#ifdef RT_USING_SMP
    isr_table[ir_self].cpu_counter[rt_hw_cpu_id()]++;
#endif
#endif
    if (isr_func)
    {
        /* Interrupt for myself. */
        param = isr_table[ir_self].param;
        /* turn to interrupt service routine */
        isr_func(ir_self, param);
    }

    /* end of interrupt */
    rt_hw_interrupt_ack(ir);
#endif
}
#else
static void _rt_hw_trap_irq(struct rt_interrupt_context *this_ctx)
{
    rt_pic_do_traps();
}
#endif

void rt_hw_trap_irq(struct rt_hw_exp_stack *regs)
{
    struct rt_interrupt_context this_ctx = {
        .context = regs,
        .node = RT_SLIST_OBJECT_INIT(this_ctx.node),
    };

    rt_interrupt_context_push(&this_ctx);
    _rt_hw_trap_irq(&this_ctx);
    rt_interrupt_context_pop();
}

#ifdef RT_USING_SMART
#define DBG_CHECK_EVENT(regs, esr) dbg_check_event(regs, esr)
#else
#define DBG_CHECK_EVENT(regs, esr) (0)
#endif

#ifndef RT_USING_PIC
void rt_hw_trap_fiq(void)
{
    void *param;
    int ir, ir_self;
    rt_isr_handler_t isr_func;
    extern struct rt_irq_desc isr_table[];

    ir = rt_hw_interrupt_get_irq();

    /* bit 10~12 is cpuid, bit 0~9 is interrup id */
    ir_self = ir & 0x3ffUL;

    /* get interrupt service routine */
    isr_func = isr_table[ir_self].handler;
    param = isr_table[ir_self].param;

    /* turn to interrupt service routine */
    isr_func(ir_self, param);

    /* end of interrupt */
    rt_hw_interrupt_ack(ir);
}
#else
void rt_hw_trap_fiq(void)
{
    rt_pic_do_traps();
}
#endif

void print_exception(unsigned long esr, unsigned long epc);
void SVC_Handler(struct rt_hw_exp_stack *regs);
void rt_hw_trap_exception(struct rt_hw_exp_stack *regs)
{
    unsigned long esr;
    unsigned char ec;

    asm volatile("mrs %0, esr_el1":"=r"(esr));
    ec = (unsigned char)((esr >> 26) & 0x3fU);

    if (DBG_CHECK_EVENT(regs, esr))
    {
        return;
    }
    else if (ec == 0x15) /* is 64bit syscall ? */
    {
        SVC_Handler(regs);
        /* never return here */
    }

#ifdef RT_USING_SMART
    /**
     * Note: check_user_stack will take lock and it will possibly be a dead-lock
     * if exception comes from kernel.
     */
    if ((regs->cpsr & 0x1f) == 0)
    {
        if (user_fault_fixable(esr, regs))
            return;
    }
    else
    {
        if (_irq_is_disable(regs->cpsr))
        {
            LOG_E("Kernel fault from interrupt/critical section");
        }
        if (rt_critical_level() != 0)
        {
            LOG_E("scheduler is not available");
        }
        else if (user_fault_fixable(esr, regs))
            return;
    }
#endif
    print_exception(esr, regs->pc);
    rt_hw_show_register(regs);
    LOG_E("current thread: %s\n", rt_thread_self()->parent.name);

#ifdef RT_USING_FINSH
    list_thread();
#endif

#ifdef RT_USING_LWP
    /* restore normal execution environment */
    __asm__ volatile("msr daifclr, 0x3\ndmb ishst\nisb\n");
    _check_fault(regs, 0, "user fault");
#endif

    struct rt_hw_backtrace_frame frame = {.fp = regs->x29, .pc = regs->pc};
    rt_backtrace_frame(rt_thread_self(), &frame);
    rt_hw_cpu_shutdown();
}

void rt_hw_trap_serror(struct rt_hw_exp_stack *regs)
{
    rt_kprintf("SError\n");
    rt_hw_show_register(regs);
    rt_kprintf("current: %s\n", rt_thread_self()->parent.name);
#ifdef RT_USING_FINSH
    list_thread();
#endif
    rt_hw_cpu_shutdown();
}