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/*
* This file is part of the MicroPython project, http://micropython.org/
*
* The MIT License (MIT)
*
* Copyright (c) 2023 Alessandro Gatti
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
// Vector table
void mtvec_table(void) __attribute__((naked, section(".text.mtvec"), aligned(256)));
// Default interrupts
#define ASSIGN_EMPTY_MACHINE_INTERRUPT(interrupt_name) \
void interrupt_name(void) __attribute__((alias("mtvec_nop")))
ASSIGN_EMPTY_MACHINE_INTERRUPT(mtvec_ssi);
ASSIGN_EMPTY_MACHINE_INTERRUPT(mtvec_msi);
ASSIGN_EMPTY_MACHINE_INTERRUPT(mtvec_sti);
ASSIGN_EMPTY_MACHINE_INTERRUPT(mtvec_mti);
ASSIGN_EMPTY_MACHINE_INTERRUPT(mtvec_sei);
ASSIGN_EMPTY_MACHINE_INTERRUPT(mtvec_mei);
ASSIGN_EMPTY_MACHINE_INTERRUPT(mtvec_plat_irq0);
ASSIGN_EMPTY_MACHINE_INTERRUPT(mtvec_plat_irq1);
ASSIGN_EMPTY_MACHINE_INTERRUPT(mtvec_plat_irq2);
ASSIGN_EMPTY_MACHINE_INTERRUPT(mtvec_plat_irq3);
ASSIGN_EMPTY_MACHINE_INTERRUPT(mtvec_plat_irq4);
ASSIGN_EMPTY_MACHINE_INTERRUPT(mtvec_plat_irq5);
ASSIGN_EMPTY_MACHINE_INTERRUPT(mtvec_plat_irq6);
ASSIGN_EMPTY_MACHINE_INTERRUPT(mtvec_plat_irq7);
ASSIGN_EMPTY_MACHINE_INTERRUPT(mtvec_plat_irq8);
ASSIGN_EMPTY_MACHINE_INTERRUPT(mtvec_plat_irq9);
ASSIGN_EMPTY_MACHINE_INTERRUPT(mtvec_plat_irq10);
ASSIGN_EMPTY_MACHINE_INTERRUPT(mtvec_plat_irq11);
ASSIGN_EMPTY_MACHINE_INTERRUPT(mtvec_plat_irq12);
ASSIGN_EMPTY_MACHINE_INTERRUPT(mtvec_plat_irq13);
ASSIGN_EMPTY_MACHINE_INTERRUPT(mtvec_plat_irq14);
ASSIGN_EMPTY_MACHINE_INTERRUPT(mtvec_plat_irq15);
void mtvec_table(void) {
__asm volatile (
".org mtvec_table + 0 \n"
"jal zero, mtvec_exception \n" // Exception Handler
".org mtvec_table + 4 \n"
"jal zero, mtvec_ssi \n" // Supervisor Software Interrupt
".org mtvec_table + 12 \n"
"jal zero, mtvec_msi \n" // Machine Software Interrupt
".org mtvec_table + 20 \n"
"jal zero, mtvec_sti \n" // Supervisor Timer Interrupt
".org mtvec_table + 28 \n"
"jal zero, mtvec_mti \n" // Machine Timer Interrupt
".org mtvec_table + 36 \n"
"jal zero, mtvec_sei \n" // Supervisor External Interrupt
".org mtvec_table + 44 \n"
"jal zero, mtvec_mei \n" // Machine External Interrupt
// Not sure how many platform interrupts QEMU handles...
".org mtvec_table + 48 \n"
"jal mtvec_plat_irq0 \n" // Platform Interrupt #0
"jal mtvec_plat_irq1 \n" // Platform Interrupt #1
"jal mtvec_plat_irq2 \n" // Platform Interrupt #2
"jal mtvec_plat_irq3 \n" // Platform Interrupt #3
"jal mtvec_plat_irq4 \n" // Platform Interrupt #4
"jal mtvec_plat_irq5 \n" // Platform Interrupt #5
"jal mtvec_plat_irq6 \n" // Platform Interrupt #6
"jal mtvec_plat_irq7 \n" // Platform Interrupt #7
"jal mtvec_plat_irq8 \n" // Platform Interrupt #8
"jal mtvec_plat_irq9 \n" // Platform Interrupt #9
"jal mtvec_plat_irq10 \n" // Platform Interrupt #10
"jal mtvec_plat_irq11 \n" // Platform Interrupt #11
"jal mtvec_plat_irq12 \n" // Platform Interrupt #12
"jal mtvec_plat_irq13 \n" // Platform Interrupt #13
"jal mtvec_plat_irq14 \n" // Platform Interrupt #14
"jal mtvec_plat_irq15 \n" // Platform Interrupt #15
:
:
: "memory"
);
}
volatile uint32_t registers_copy[35] = { 0 };
const char *exception_causes[] = {
"Reserved", // 0
"Supervisor software interrupt", // 1
"Machine software interrupt", // 2
"Supervisor timer interrupt", // 3
"Machine timer interrupt", // 4
"Supervisor external interrupt", // 5
"Machine external interrupt", // 6
"Designated for platform use", // 7
"Instruction address misaligned", // 8
"Instruction address fault", // 9
"Illegal instruction", // 10
"Breakpoint", // 11
"Load address misaligned", // 12
"Load address fault", // 13
"Store/AMO address misaligned", // 14
"Store/AMO access fault", // 15
"Environment call from U-mode", // 16
"Environment call from S-mode", // 17
"Environment call from M-mode", // 18
"Instruction page fault", // 19
"Load page fault", // 20
"Store/AMO page fault", // 21
"Designated for custom use" // 22
};
const char *lookup_cause(uint32_t mcause) {
if (mcause & 0x80000000) {
switch (mcause & 0x7FFFFFFF) {
case 1:
return exception_causes[1];
case 3:
return exception_causes[2];
case 5:
return exception_causes[3];
case 7:
return exception_causes[4];
case 9:
return exception_causes[5];
case 11:
return exception_causes[6];
default:
return ((mcause & 0x7FFFFFFF) >= 16) ?
exception_causes[7] :
exception_causes[0];
}
}
switch (mcause) {
case 0:
return exception_causes[8];
case 1:
return exception_causes[9];
case 2:
return exception_causes[10];
case 3:
return exception_causes[11];
case 4:
return exception_causes[12];
case 5:
return exception_causes[13];
case 6:
return exception_causes[14];
case 7:
return exception_causes[15];
case 8:
return exception_causes[16];
case 9:
return exception_causes[17];
case 11:
return exception_causes[18];
case 12:
return exception_causes[19];
case 13:
return exception_causes[20];
case 15:
return exception_causes[21];
default: {
if ((mcause >= 24 && mcause <= 31) ||
(mcause >= 48 && mcause <= 63)) {
return exception_causes[22];
}
return exception_causes[0];
}
}
}
#pragma GCC push_options
#pragma GCC optimize ("align-functions=4")
__attribute__((interrupt("machine"), weak)) void mtvec_nop(void) {
}
__attribute__((interrupt("machine"), weak)) void mtvec_exception(void) {
__asm volatile (
"csrrw x31, mscratch, x31 \n" // Save X31
"la x31, registers_copy \n" // Load target address
"sw x1, 0(x31) \n" // Save X1
"sw x2, 4(x31) \n" // Save X2
"sw x3, 8(x31) \n" // Save X3
"sw x4, 12(x31) \n" // Save X4
"sw x5, 16(x31) \n" // Save X5
"sw x6, 20(x31) \n" // Save X6
"sw x7, 24(x31) \n" // Save X7
"sw x8, 28(x31) \n" // Save X8
"sw x9, 32(x31) \n" // Save X9
"sw x10, 36(x31) \n" // Save X10
"sw x11, 40(x31) \n" // Save X11
"sw x12, 44(x31) \n" // Save X12
"sw x13, 48(x31) \n" // Save X13
"sw x14, 52(x31) \n" // Save X14
"sw x15, 56(x31) \n" // Save X15
"sw x16, 60(x31) \n" // Save X16
"sw x17, 64(x31) \n" // Save X17
"sw x18, 68(x31) \n" // Save X18
"sw x19, 72(x31) \n" // Save X19
"sw x20, 76(x31) \n" // Save X20
"sw x21, 80(x31) \n" // Save X21
"sw x22, 84(x31) \n" // Save X22
"sw x23, 88(x31) \n" // Save X23
"sw x24, 92(x31) \n" // Save X24
"sw x25, 98(x31) \n" // Save X25
"sw x26, 100(x31) \n" // Save X26
"sw x27, 104(x31) \n" // Save X27
"sw x28, 108(x31) \n" // Save X28
"sw x29, 112(x31) \n" // Save X29
"sw x30, 116(x31) \n" // Save X30
"csrr x30, mscratch \n" // Restore X31
"sw x30, 120(x31) \n" // Save X31
"csrr x30, mepc \n" // Load MEPC
"sw x30, 124(x31) \n" // Save MEPC
"csrr x30, mcause \n" // Load MCAUSE
"sw x30, 128(x31) \n" // Save MCAUSE
"csrr x30, mtval \n" // Load MTVAL
"sw x30, 132(x31) \n" // Save MTVAL
"csrr x30, mstatus \n" // Load MSTATUS
"sw x30, 138(x31) \n" // Save MSTATUS
"lw x30, 116(x31) \n" // Restore X30
"lw x31, 120(x31) \n" // Restore X31
:
:
: "memory"
);
printf("\nMACHINE EXCEPTION CAUGHT:\n\n");
printf(" RA=%08lX SP=%08lX GP=%08lX TP=%08lX T0=%08lX T1=%08lX\n",
registers_copy[0], registers_copy[1], registers_copy[2],
registers_copy[3], registers_copy[4], registers_copy[5]);
printf(" T2=%08lX S0=%08lX S1=%08lX A0=%08lX A1=%08lX A2=%08lX\n",
registers_copy[6], registers_copy[7], registers_copy[8],
registers_copy[9], registers_copy[10], registers_copy[11]);
printf(" A3=%08lX A4=%08lX A5=%08lX A6=%08lX A7=%08lX S2=%08lX\n",
registers_copy[12], registers_copy[13], registers_copy[14],
registers_copy[15], registers_copy[16], registers_copy[17]);
printf(" S3=%08lX S4=%08lX S5=%08lX S6=%08lX S7=%08lX S8=%08lX\n",
registers_copy[18], registers_copy[19], registers_copy[20],
registers_copy[21], registers_copy[22], registers_copy[23]);
printf(" S9=%08lX S10=%08lX S11=%08lX T3=%08lX T4=%08lX T5=%08lX\n",
registers_copy[24], registers_copy[25], registers_copy[26],
registers_copy[27], registers_copy[28], registers_copy[29]);
printf(" T6=%08lX\n\n", registers_copy[30]);
printf(" MEPC=%08lX MTVAL=%08lX MSTATUS=%08lx MCAUSE=%08lx (%s)\n",
registers_copy[31], registers_copy[33], registers_copy[34],
registers_copy[32], lookup_cause(registers_copy[32]));
exit(-1);
}
#pragma GCC pop_options
void set_interrupt_table(void) {
__asm volatile (
"csrrci s0, mstatus, 8 \n" // S0 = MSTATUS & ~MIE
"csrw mstatus, s0 \n" // Global machine interrupts are disabled
"csrw mie, zero \n" // Disable machine interrupts
"csrw mip, zero \n" // Clear pending machine interrupts
"addi s0, %0, 1 \n" // Vectored machine interrupts enabled
"csrw mtvec, s0 \n" // Set new machine vector table
"csrrsi s0, mstatus, 8 \n" // S0 = MSTATUS | MIE
"csrw mstatus, s0 \n" // Global machine interrupts are enabled
:
: "r" (mtvec_table)
: "memory"
);
}
|
