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/******************************************************************************

 * @file

 * @copyright Copyright 2017 GNSS Sensor Ltd. All right reserved.

 * @author    Sergey Khabarov - sergeykhbr@gmail.com

 * @brief     General interrupt handler called from assembler.

******************************************************************************/

#include <string.h>

#include "axi_maps.h"

typedef void (*IRQ_HANDLER)(int idx, void *args);

typedef union csr_mcause_type {

    struct bits_type {

        uint64_t code   : 63;   // 11 - Machine external interrupt

        uint64_t irq    : 1;

    } bits;

    uint64_t value;

} csr_mcause_type;

extern void print_uart(const char *buf, int sz);

extern void print_uart_hex(long val);

long handle_trap(long cause, long epc, long long regs[32]) {

    /**

     * Pending interrupt bit is cleared in the crt.S file by calling:

     *      csrc mip, MIP_MSIP

     * If we woudn't do it the interrupt handler will be called infinitly

     *

     * Rise interrupt from the software maybe done sending a self-IPI:

     *      csrwi mipi, 0

     */

    irqctrl_map *p_irqctrl = (irqctrl_map *)ADDR_NASTI_SLAVE_IRQCTRL;

    IRQ_HANDLER irq_handler = (IRQ_HANDLER)p_irqctrl->isr_table;

    uint32_t pending;

    csr_mcause_type mcause;

    mcause.value = cause;

    p_irqctrl->dbg_cause = cause;

    p_irqctrl->dbg_epc = epc;

    p_irqctrl->irq_lock = 1;

    pending = p_irqctrl->irq_pending;

    p_irqctrl->irq_clear = pending;

    p_irqctrl->irq_lock = 0;

    if (mcause.bits.irq == 0x1 && mcause.bits.code == 11) {

        for (int i = 0; i < CFG_IRQ_TOTAL; i++) {

            if (pending & 0x1) {

                p_irqctrl->irq_cause_idx = i;

                irq_handler(i, NULL);

            }

            pending >>= 1;

        }

    } else {

       print_uart("mcause:", 7);

       print_uart_hex(cause);

       print_uart(",mepc:", 6);

       print_uart_hex(epc);

       print_uart("\r\n", 2);

       /// Exception trap

       ((gpio_map *)ADDR_NASTI_SLAVE_GPIO)->led = 0xF0;

       while (1) {}

    }

    return epc;

}