/*   ==================================================================

     >>>>>>>>>>>>>>>>>>>>>>> COPYRIGHT NOTICE <<<<<<<<<<<<<<<<<<<<<<<<<
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       IMPORTANT: THIS FILE IS USED BY OR GENERATED BY the LATTICE PROPEL™
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     ================================================================== */

#include "cpu.h"
#include "riscv.h"
#include "debug.h"


extern void trap_entry(void);
extern void nmi_entry(void);
extern void trap_vector(void);
extern void isr_callback(uint32_t mcause, uint32_t mepc, void *cxt);
extern void nmi_callback(uint32_t mcause);
extern uint32_t esr_callback(uint32_t mcause, uint32_t mepc, void *cxt);
extern void exception_init();



context_t g_ctx = { 0 };
context_t *global_context()
{
    return &g_ctx;
}


void trap_init()
{
    w_mscratch((reg_t)global_context());

    exception_init();

    if (MTVEC_MODE_SEL == MTVEC_MODE_DIRECT)
    {
        w_mtvec((reg_t)trap_entry);
    }
    else
    {
        w_mtvec((reg_t)trap_vector | MTVEC_MODE_VECTORED);
    }

    csr_write(CSR_MNVEC, (reg_t)nmi_entry);
}


reg_t trap_handler(reg_t epc, reg_t cause, context_t *cxt)
{
    reg_t return_pc = epc;
    reg_t cause_code = cause & 0xfff;

    if (cause & 0x80000000) {
        /* Asynchronous trap - interrupt */
        // DEBUG("interrupt!, cause=%d\r\n", cause_code);
        isr_callback(cause_code, epc, cxt);
    } else {
        /* Synchronous trap - exception */
        // DEBUG("exception!, cause=%d, epc=0x%08x\r\n", cause_code, epc);
        return_pc = esr_callback(cause_code, epc, cxt);
    }

    return return_pc;
}


uint32_t g_trap_depth = 0;
uint32_t trap_depth()
{
    return g_trap_depth;
}


void nmi_handler(reg_t epc, reg_t cause, context_t *cxt)
{
    ERROR("nmi interrupt, epc=0x%08x, cause=%d\r\n", epc, cause);
    reg_t cause_code = cause & 0xfff;
    nmi_callback(cause_code);
}