blob: f9a1428a486c6bf7dc01200d7611d7c40a15ac98 [file] [log] [blame]
// 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 <linux/compat.h>
#include <efi_loader.h>
#include <hang.h>
#include <interrupt.h>
#include <irq_func.h>
#include <asm/global_data.h>
#include <asm/ptrace.h>
#include <asm/system.h>
#include <asm/encoding.h>
#include <semihosting.h>
DECLARE_GLOBAL_DATA_PTR;
static struct resume_data *resume;
void set_resume(struct resume_data *data)
{
resume = data;
}
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("\nSP: " 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",
regs->t4, regs->t5, regs->t6);
#endif
}
static void __maybe_unused show_backtrace(struct pt_regs *regs)
{
uintptr_t *fp = (uintptr_t *)regs->s0;
unsigned count = 0;
ulong ra;
printf("\nbacktrace:\n");
/* there are a few entry points where the s0 register is
* set to gd, so to avoid changing those, just abort if
* the value is the same */
while (fp != NULL && fp != (uintptr_t *)gd) {
ra = fp[-1];
printf("%3d: FP: " REG_FMT " RA: " REG_FMT,
count, (ulong)fp, ra);
if (gd && gd->flags & GD_FLG_RELOC)
printf(" - RA: " REG_FMT " reloc adjusted\n",
ra - gd->reloc_off);
else
printf("\n");
fp = (uintptr_t *)fp[-2];
count++;
}
}
/**
* instr_len() - get instruction length
*
* @i: low 16 bits of the instruction
* Return: number of u16 in instruction
*/
static int instr_len(u16 i)
{
if ((i & 0x03) != 0x03)
return 1;
/* Instructions with more than 32 bits are not yet specified */
return 2;
}
/**
* show_code() - display code leading to exception
*
* @epc: program counter
*/
static void show_code(ulong epc)
{
u16 *pos = (u16 *)(epc & ~1UL);
int i, len = instr_len(*pos);
printf("\nCode: ");
for (i = -8; i; ++i)
printf("%04x ", pos[i]);
printf("(");
for (i = 0; i < len; ++i)
printf("%04x%s", pos[i], i + 1 == len ? ")\n" : " ");
}
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 (resume) {
resume->code = code;
longjmp(resume->jump, 1);
}
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);
/* Print relocation adjustments, but only if gd is initialized */
if (gd && gd->flags & GD_FLG_RELOC)
printf("EPC: " REG_FMT " RA: " REG_FMT " reloc adjusted\n",
epc - gd->reloc_off, regs->ra - gd->reloc_off);
show_regs(regs);
if (CONFIG_IS_ENABLED(FRAMEPOINTER))
show_backtrace(regs);
show_code(epc);
show_efi_loaded_images(epc);
panic("\n");
}
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;
/* An UEFI application may have changed gd. Restore U-Boot's gd. */
efi_restore_gd();
if (cause == CAUSE_BREAKPOINT &&
CONFIG_IS_ENABLED(SEMIHOSTING_FALLBACK)) {
ulong pre_addr = epc - 4, post_addr = epc + 4;
/* Check for prior and post addresses to be in same page. */
if ((pre_addr & ~(PAGE_SIZE - 1)) ==
(post_addr & ~(PAGE_SIZE - 1))) {
u32 pre = *(u32 *)pre_addr;
u32 post = *(u32 *)post_addr;
/* Check for semihosting, i.e.:
* slli zero,zero,0x1f
* ebreak
* srai zero,zero,0x7
*/
if (pre == 0x01f01013 && post == 0x40705013) {
disable_semihosting();
epc += 4;
return epc;
}
}
}
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)
{
}