u-boot/arch/riscv/lib/interrupts.c
Heinrich Schuchardt 7c6ca03eae riscv: additional crash information
If an exception occurs, the relocated program counter and return address
are required for an analysis.

With this patch you get:

    => exception undefined

    Unhandled exception: Illegal instruction
    EPC: 0000000080595908 RA: 000000008059c0c6 TVAL: 000000008030c01e
    EPC: 0000000080007908 RA: 000000008000e0c6 reloc adjusted

We can use the relocated addresses to find the involved functions in
u.boot.map:

    .text.do_undefined
                0x0000000080007908        0x8 cmd/built-in.o
    .text.cmd_process
                0x000000008000dfcc      0x11a common/built-in.o
                0x000000008000dfcc                cmd_process

If an exception occurs in an UEFI binary additionally the load addresses of
the UEFI binaries are needed. With this patch:

    => setenv efi_selftest exception
    => bootefi selftest

    Unhandled exception: Illegal instruction
    EPC: 000000008042e18a RA: 000000008042e18a TVAL: 000000008030c01e
    EPC: 000000007fea018a RA: 000000007fea018a reloc adjusted

    UEFI image [0x0000000000000000:0xffffffffffffffff] '/\selftest'
    UEFI image [0x000000008042e000:0x000000008042e43f] pc=0x18a '/bug.efi'

The value pc=0x18a matches the position of the illegal instruction in
efi_selftest_miniapp_exception.efi (loaded as /bug.efi);

    asm volatile (".word 0xffffffff\n");

    00000180   93 85 C5 11  1C 64 22 85  82 97 FF FF  FF FF 1C 64

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Reviewed-by: Sean Anderson <seanga2@gmail.com>
Tested-by: Sean Anderson <seanga2@gmail.com>
Reviewed-by: Bin Meng <bin.meng@windriver.com>
Reviewed-by: Rick Chen <rick@andestech.com>
2020-08-14 14:39:41 +08:00

147 lines
3.6 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (c) 2016-17 Microsemi Corporation.
* Padmarao Begari, Microsemi Corporation <padmarao.begari@microsemi.com>
*
* Copyright (C) 2017 Andes Technology Corporation
* Rick Chen, Andes Technology Corporation <rick@andestech.com>
*
* Copyright (C) 2019 Sean Anderson <seanga2@gmail.com>
*/
#include <common.h>
#include <efi_loader.h>
#include <hang.h>
#include <irq_func.h>
#include <asm/ptrace.h>
#include <asm/system.h>
#include <asm/encoding.h>
DECLARE_GLOBAL_DATA_PTR;
static void show_efi_loaded_images(uintptr_t epc)
{
efi_print_image_infos((void *)epc);
}
static void show_regs(struct pt_regs *regs)
{
#ifdef CONFIG_SHOW_REGS
printf("SP: " REG_FMT " GP: " REG_FMT " TP: " REG_FMT "\n",
regs->sp, regs->gp, regs->tp);
printf("T0: " REG_FMT " T1: " REG_FMT " T2: " REG_FMT "\n",
regs->t0, regs->t1, regs->t2);
printf("S0: " REG_FMT " S1: " REG_FMT " A0: " REG_FMT "\n",
regs->s0, regs->s1, regs->a0);
printf("A1: " REG_FMT " A2: " REG_FMT " A3: " REG_FMT "\n",
regs->a1, regs->a2, regs->a3);
printf("A4: " REG_FMT " A5: " REG_FMT " A6: " REG_FMT "\n",
regs->a4, regs->a5, regs->a6);
printf("A7: " REG_FMT " S2: " REG_FMT " S3: " REG_FMT "\n",
regs->a7, regs->s2, regs->s3);
printf("S4: " REG_FMT " S5: " REG_FMT " S6: " REG_FMT "\n",
regs->s4, regs->s5, regs->s6);
printf("S7: " REG_FMT " S8: " REG_FMT " S9: " REG_FMT "\n",
regs->s7, regs->s8, regs->s9);
printf("S10: " REG_FMT " S11: " REG_FMT " T3: " REG_FMT "\n",
regs->s10, regs->s11, regs->t3);
printf("T4: " REG_FMT " T5: " REG_FMT " T6: " REG_FMT "\n\n",
regs->t4, regs->t5, regs->t6);
#endif
}
static void _exit_trap(ulong code, ulong epc, ulong tval, struct pt_regs *regs)
{
static const char * const exception_code[] = {
"Instruction address misaligned",
"Instruction access fault",
"Illegal instruction",
"Breakpoint",
"Load address misaligned",
"Load access fault",
"Store/AMO address misaligned",
"Store/AMO access fault",
"Environment call from U-mode",
"Environment call from S-mode",
"Reserved",
"Environment call from M-mode",
"Instruction page fault",
"Load page fault",
"Reserved",
"Store/AMO page fault",
};
if (code < ARRAY_SIZE(exception_code))
printf("Unhandled exception: %s\n", exception_code[code]);
else
printf("Unhandled exception code: %ld\n", code);
printf("EPC: " REG_FMT " RA: " REG_FMT " TVAL: " REG_FMT "\n",
epc, regs->ra, tval);
if (gd->flags & GD_FLG_RELOC)
printf("EPC: " REG_FMT " RA: " REG_FMT " reloc adjusted\n\n",
epc - gd->reloc_off, regs->ra - gd->reloc_off);
show_regs(regs);
show_efi_loaded_images(epc);
hang();
}
int interrupt_init(void)
{
return 0;
}
/*
* enable interrupts
*/
void enable_interrupts(void)
{
}
/*
* disable interrupts
*/
int disable_interrupts(void)
{
return 0;
}
ulong handle_trap(ulong cause, ulong epc, ulong tval, struct pt_regs *regs)
{
ulong is_irq, irq;
is_irq = (cause & MCAUSE_INT);
irq = (cause & ~MCAUSE_INT);
if (is_irq) {
switch (irq) {
case IRQ_M_EXT:
case IRQ_S_EXT:
external_interrupt(0); /* handle external interrupt */
break;
case IRQ_M_TIMER:
case IRQ_S_TIMER:
timer_interrupt(0); /* handle timer interrupt */
break;
default:
_exit_trap(cause, epc, tval, regs);
break;
};
} else {
_exit_trap(cause, epc, tval, regs);
}
return epc;
}
/*
*Entry Point for PLIC Interrupt Handler
*/
__attribute__((weak)) void external_interrupt(struct pt_regs *regs)
{
}
__attribute__((weak)) void timer_interrupt(struct pt_regs *regs)
{
}