arch/riscv/lib/interrupts.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Copyright (c) 2016-17 Microsemi Corporation.
   4  * Padmarao Begari, Microsemi Corporation <padmarao.begari@microsemi.com>
   5  *
   6  * Copyright (C) 2017 Andes Technology Corporation
   7  * Rick Chen, Andes Technology Corporation <rick@andestech.com>
   8  */
   9
  10 #include <common.h>
  11 #include <asm/ptrace.h>
  12 #include <asm/system.h>
  13 #include <asm/encoding.h>
  14
  15 static void _exit_trap(ulong code, ulong epc, struct pt_regs *regs);
  16
  17 int interrupt_init(void)
  18 {
  19         return 0;
  20 }
  21
  22 /*
  23  * enable interrupts
  24  */
  25 void enable_interrupts(void)
  26 {
  27 }
  28
  29 /*
  30  * disable interrupts
  31  */
  32 int disable_interrupts(void)
  33 {
  34         return 0;
  35 }
  36
  37 ulong handle_trap(ulong cause, ulong epc, struct pt_regs *regs)
  38 {
  39         ulong is_irq, irq;
  40
  41         is_irq = (cause & MCAUSE_INT);
  42         irq = (cause & ~MCAUSE_INT);
  43
  44         if (is_irq) {
  45                 switch (irq) {
  46                 case IRQ_M_EXT:
  47                 case IRQ_S_EXT:
  48                         external_interrupt(0);  /* handle external interrupt */
  49                         break;
  50                 case IRQ_M_TIMER:
  51                 case IRQ_S_TIMER:
  52                         timer_interrupt(0);     /* handle timer interrupt */
  53                         break;
  54                 default:
  55                         _exit_trap(cause, epc, regs);
  56                         break;
  57                 };
  58         } else {
  59                 _exit_trap(cause, epc, regs);
  60         }
  61
  62         return epc;
  63 }
  64
  65 /*
  66  *Entry Point for PLIC Interrupt Handler
  67  */
  68 __attribute__((weak)) void external_interrupt(struct pt_regs *regs)
  69 {
  70 }
  71
  72 __attribute__((weak)) void timer_interrupt(struct pt_regs *regs)
  73 {
  74 }
  75
  76 static void _exit_trap(ulong code, ulong epc, struct pt_regs *regs)
  77 {
  78         static const char * const exception_code[] = {
  79                 "Instruction address misaligned",
  80                 "Instruction access fault",
  81                 "Illegal instruction",
  82                 "Breakpoint",
  83                 "Load address misaligned",
  84                 "Load access fault",
  85                 "Store/AMO address misaligned",
  86                 "Store/AMO access fault",
  87                 "Environment call from U-mode",
  88                 "Environment call from S-mode",
  89                 "Reserved",
  90                 "Environment call from M-mode",
  91                 "Instruction page fault",
  92                 "Load page fault",
  93                 "Reserved",
  94                 "Store/AMO page fault",
  95         };
  96
  97         if (code < ARRAY_SIZE(exception_code)) {
  98                 printf("exception code: %ld , %s , epc %lx , ra %lx\n",
  99                        code, exception_code[code], epc, regs->ra);
 100         } else {
 101                 printf("Reserved\n");
 102         }
 103
 104         hang();
 105 }