// SPDX-License-Identifier: GPL-2.0
// Copyright (C) 2005-2017 Andes Technology Corporation
#include <linux/module.h>
#include <linux/personality.h>
#include <linux/kallsyms.h>
#include <linux/hardirq.h>
#include <linux/kdebug.h>
#include <linux/sched/task_stack.h>
#include <linux/uaccess.h>
#include <linux/ftrace.h>
#include <asm/proc-fns.h>
#include <asm/unistd.h>
#include <asm/fpu.h>
#include <linux/ptrace.h>
#include <nds32_intrinsic.h>
extern void show_pte(struct mm_struct *mm, unsigned long addr);
/*
* Dump out the contents of some memory nicely...
*/
void dump_mem(const char *lvl, unsigned long bottom, unsigned long top)
{
unsigned long first;
mm_segment_t fs;
int i;
/*
* We need to switch to kernel mode so that we can use __get_user
* to safely read from kernel space. Note that we now dump the
* code first, just in case the backtrace kills us.
*/
fs = get_fs();
set_fs(KERNEL_DS);
pr_emerg("%s(0x%08lx to 0x%08lx)\n", lvl, bottom, top);
for (first = bottom & ~31; first < top; first += 32) {
unsigned long p;
char str[sizeof(" 12345678") * 8 + 1];
memset(str, ' ', sizeof(str));
str[sizeof(str) - 1] = '\0';
for (p = first, i = 0; i < 8 && p < top; i++, p += 4) {
if (p >= bottom && p < top) {
unsigned long val;
if (__get_user(val, (unsigned long *)p) == 0)
sprintf(str + i * 9, " %08lx", val);
else
sprintf(str + i * 9, " ????????");
}
}
pr_emerg("%s%04lx:%s\n", lvl, first & 0xffff, str);
}
set_fs(fs);
}
EXPORT_SYMBOL(dump_mem);
static void dump_instr(struct pt_regs *regs)
{
unsigned long addr = instruction_pointer(regs);
mm_segment_t fs;
char str[sizeof("00000000 ") * 5 + 2 + 1], *p = str;
int i;
return;
/*
* We need to switch to kernel mode so that we can use __get_user
* to safely read from kernel space. Note that we now dump the
* code first, just in case the backtrace kills us.
*/
fs = get_fs();
set_fs(KERNEL_DS);
pr_emerg("Code: ");
for (i = -4; i < 1; i++) {
unsigned int val, bad;
bad = __get_user(val, &((u32 *) addr)[i]);
if (!bad) {
p += sprintf(p, i == 0 ? "(%08x) " : "%08x ", val);
} else {
p += sprintf(p, "bad PC value");
break;
}
}
pr_emerg("Code: %s\n", str);
set_fs(fs);
}
#define LOOP_TIMES (100)
static void __dump(struct task_struct *tsk, unsigned long *base_reg)
{
unsigned long ret_addr;
int cnt = LOOP_TIMES, graph = 0;
pr_emerg("Call Trace:\n");
if (!IS_ENABLED([31mCONFIG_FRAME_POINTER[0m)) {
while (!kstack_end(base_reg)) {
ret_addr = *base_reg++;
if (__kernel_text_address(ret_addr)) {
ret_addr = ftrace_graph_ret_addr(
tsk, &graph, ret_addr, NULL);
print_ip_sym(ret_addr);
}
if (--cnt < 0)
break;
}
} else {
while (!kstack_end((void *)base_reg) &&
!((unsigned long)base_reg & 0x3) &&
((unsigned long)base_reg >= TASK_SIZE)) {
unsigned long next_fp;
ret_addr = base_reg[LP_OFFSET];
next_fp = base_reg[FP_OFFSET];
if (__kernel_text_address(ret_addr)) {
ret_addr = ftrace_graph_ret_addr(
tsk, &graph, ret_addr, NULL);
print_ip_sym(ret_addr);
}
if (--cnt < 0)
break;
base_reg = (unsigned long *)next_fp;
}
}
pr_emerg("\n");
}
void show_stack(struct task_struct *tsk, unsigned long *sp)
{
unsigned long *base_reg;
if (!tsk)
tsk = current;
if (!IS_ENABLED([31mCONFIG_FRAME_POINTER[0m)) {
if (tsk != current)
base_reg = (unsigned long *)(tsk->thread.cpu_context.sp);
else
__asm__ __volatile__("\tori\t%0, $sp, #0\n":"=r"(base_reg));
} else {
if (tsk != current)
base_reg = (unsigned long *)(tsk->thread.cpu_context.fp);
else
__asm__ __volatile__("\tori\t%0, $fp, #0\n":"=r"(base_reg));
}
__dump(tsk, base_reg);
barrier();
}
DEFINE_SPINLOCK(die_lock);
/*
* This function is protected against re-entrancy.
*/
void die(const char *str, struct pt_regs *regs, int err)
{
struct task_struct *tsk = current;
static int die_counter;
console_verbose();
spin_lock_irq(&die_lock);
bust_spinlocks(1);
pr_emerg("Internal error: %s: %x [#%d]\n", str, err, ++die_counter);
print_modules();
pr_emerg("CPU: %i\n", smp_processor_id());
show_regs(regs);
pr_emerg("Process %s (pid: %d, stack limit = 0x%p)\n",
tsk->comm, tsk->pid, end_of_stack(tsk));
if (!user_mode(regs) || in_interrupt()) {
dump_mem("Stack: ", regs->sp, (regs->sp + PAGE_SIZE) & PAGE_MASK);
dump_instr(regs);
dump_stack();
}
bust_spinlocks(0);
spin_unlock_irq(&die_lock);
do_exit(SIGSEGV);
}
EXPORT_SYMBOL(die);
void die_if_kernel(const char *str, struct pt_regs *regs, int err)
{
if (user_mode(regs))
return;
die(str, regs, err);
}
int bad_syscall(int n, struct pt_regs *regs)
{
if (current->personality != PER_LINUX) {
send_sig(SIGSEGV, current, 1);
return regs->uregs[0];
}
force_sig_fault(SIGILL, ILL_ILLTRP,
(void __user *)instruction_pointer(regs) - 4);
die_if_kernel("Oops - bad syscall", regs, n);
return regs->uregs[0];
}
void __pte_error(const char *file, int line, unsigned long val)
{
pr_emerg("%s:%d: bad pte %08lx.\n", file, line, val);
}
void __pmd_error(const char *file, int line, unsigned long val)
{
pr_emerg("%s:%d: bad pmd %08lx.\n", file, line, val);
}
void __pgd_error(const char *file, int line, unsigned long val)
{
pr_emerg("%s:%d: bad pgd %08lx.\n", file, line, val);
}
extern char *exception_vector, *exception_vector_end;
void __init trap_init(void)
{
return;
}
void __init early_trap_init(void)
{
unsigned long ivb = 0;
unsigned long base = PAGE_OFFSET;
memcpy((unsigned long *)base, (unsigned long *)&exception_vector,
((unsigned long)&exception_vector_end -
(unsigned long)&exception_vector));
ivb = __nds32__mfsr(NDS32_SR_IVB);
/* Check platform support. */
if (((ivb & IVB_mskNIVIC) >> IVB_offNIVIC) < 2)
panic
("IVIC mode is not allowed on the platform with interrupt controller\n");
__nds32__mtsr((ivb & ~IVB_mskESZ) | (IVB_valESZ16 << IVB_offESZ) |
IVB_BASE, NDS32_SR_IVB);
__nds32__mtsr(INT_MASK_INITAIAL_VAL, NDS32_SR_INT_MASK);
/*
* 0x800 = 128 vectors * 16byte.
* It should be enough to flush a page.
*/
cpu_cache_wbinval_page(base, true);
}
static void send_sigtrap(struct pt_regs *regs, int error_code, int si_code)
{
struct task_struct *tsk = current;
tsk->thread.trap_no = ENTRY_DEBUG_RELATED;
tsk->thread.error_code = error_code;
force_sig_fault(SIGTRAP, si_code,
(void __user *)instruction_pointer(regs));
}
void do_debug_trap(unsigned long entry, unsigned long addr,
unsigned long type, struct pt_regs *regs)
{
if (notify_die(DIE_OOPS, "Oops", regs, addr, type, SIGTRAP)
== NOTIFY_STOP)
return;
if (user_mode(regs)) {
/* trap_signal */
send_sigtrap(regs, 0, TRAP_BRKPT);
} else {
/* kernel_trap */
if (!fixup_exception(regs))
die("unexpected kernel_trap", regs, 0);
}
}
void unhandled_interruption(struct pt_regs *regs)
{
pr_emerg("unhandled_interruption\n");
show_regs(regs);
if (!user_mode(regs))
do_exit(SIGKILL);
force_sig(SIGKILL);
}
void unhandled_exceptions(unsigned long entry, unsigned long addr,
unsigned long type, struct pt_regs *regs)
{
pr_emerg("Unhandled Exception: entry: %lx addr:%lx itype:%lx\n", entry,
addr, type);
show_regs(regs);
if (!user_mode(regs))
do_exit(SIGKILL);
force_sig(SIGKILL);
}
extern int do_page_fault(unsigned long entry, unsigned long addr,
unsigned int error_code, struct pt_regs *regs);
/*
* 2:DEF dispatch for TLB MISC exception handler
*/
void do_dispatch_tlb_misc(unsigned long entry, unsigned long addr,
unsigned long type, struct pt_regs *regs)
{
type = type & (ITYPE_mskINST | ITYPE_mskETYPE);
if ((type & ITYPE_mskETYPE) < 5) {
/* Permission exceptions */
do_page_fault(entry, addr, type, regs);
} else
unhandled_exceptions(entry, addr, type, regs);
}
void do_revinsn(struct pt_regs *regs)
{
pr_emerg("Reserved Instruction\n");
show_regs(regs);
if (!user_mode(regs))
do_exit(SIGILL);
force_sig(SIGILL);
}
#ifdef [31mCONFIG_ALIGNMENT_TRAP[0m
extern int unalign_access_mode;
extern int do_unaligned_access(unsigned long addr, struct pt_regs *regs);
#endif
void do_dispatch_general(unsigned long entry, unsigned long addr,
unsigned long itype, struct pt_regs *regs,
unsigned long oipc)
{
unsigned int swid = itype >> ITYPE_offSWID;
unsigned long type = itype & (ITYPE_mskINST | ITYPE_mskETYPE);
if (type == ETYPE_ALIGNMENT_CHECK) {
#ifdef [31mCONFIG_ALIGNMENT_TRAP[0m
/* Alignment check */
if (user_mode(regs) && unalign_access_mode) {
int ret;
ret = do_unaligned_access(addr, regs);
if (ret == 0)
return;
if (ret == -EFAULT)
pr_emerg
("Unhandled unaligned access exception\n");
}
#endif
do_page_fault(entry, addr, type, regs);
} else if (type == ETYPE_RESERVED_INSTRUCTION) {
/* Reserved instruction */
do_revinsn(regs);
} else if (type == ETYPE_COPROCESSOR) {
/* Coprocessor */
#if IS_ENABLED([31mCONFIG_FPU[0m)
unsigned int fucop_exist = __nds32__mfsr(NDS32_SR_FUCOP_EXIST);
unsigned int cpid = ((itype & ITYPE_mskCPID) >> ITYPE_offCPID);
if ((cpid == FPU_CPID) &&
(fucop_exist & FUCOP_EXIST_mskCP0ISFPU)) {
unsigned int subtype = (itype & ITYPE_mskSTYPE);
if (true == do_fpu_exception(subtype, regs))
return;
}
#endif
unhandled_exceptions(entry, addr, type, regs);
} else if (type == ETYPE_TRAP && swid == SWID_RAISE_INTERRUPT_LEVEL) {
/* trap, used on v3 EDM target debugging workaround */
/*
* DIPC(OIPC) is passed as parameter before
* interrupt is enabled, so the DIPC will not be corrupted
* even though interrupts are coming in
*/
/*
* 1. update ipc
* 2. update pt_regs ipc with oipc
* 3. update pt_regs ipsw (clear DEX)
*/
__asm__ volatile ("mtsr %0, $IPC\n\t"::"r" (oipc));
regs->ipc = oipc;
if (regs->pipsw & PSW_mskDEX) {
pr_emerg
("Nested Debug exception is possibly happened\n");
pr_emerg("ipc:%08x pipc:%08x\n",
(unsigned int)regs->ipc,
(unsigned int)regs->pipc);
}
do_debug_trap(entry, addr, itype, regs);
regs->ipsw &= ~PSW_mskDEX;
} else
unhandled_exceptions(entry, addr, type, regs);
}