Orange Pi5 kernel

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * OpenRISC traps.c
 *
 * Linux architectural port borrowing liberally from similar works of
 * others.  All original copyrights apply as per the original source
 * declaration.
 *
 * Modifications for the OpenRISC architecture:
 * Copyright (C) 2003 Matjaz Breskvar <phoenix@bsemi.com>
 * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
 *
 *  Here we handle the break vectors not used by the system call
 *  mechanism, as well as some general stack/register dumping
 *  things.
 */
 
#include <linux/init.h>
#include <linux/sched.h>
#include <linux/sched/debug.h>
#include <linux/sched/task_stack.h>
#include <linux/kernel.h>
#include <linux/extable.h>
#include <linux/kmod.h>
#include <linux/string.h>
#include <linux/errno.h>
#include <linux/ptrace.h>
#include <linux/timer.h>
#include <linux/mm.h>
#include <linux/kallsyms.h>
#include <linux/uaccess.h>
 
#include <asm/io.h>
#include <asm/unwinder.h>
#include <asm/sections.h>
 
int kstack_depth_to_print = 0x180;
int lwa_flag;
unsigned long __user *lwa_addr;
 
void print_trace(void *data, unsigned long addr, int reliable)
{
<------>const char *loglvl = data;
 
<------>printk("%s[<%p>] %s%pS\n", loglvl, (void *) addr, reliable ? "" : "? ",
<------>       (void *) addr);
}
 
/* displays a short stack trace */
void show_stack(struct task_struct *task, unsigned long *esp, const char *loglvl)
{
<------>if (esp == NULL)
<------><------>esp = (unsigned long *)&esp;
 
<------>printk("%sCall trace:\n", loglvl);
<------>unwind_stack((void *)loglvl, esp, print_trace);
}
 
void show_registers(struct pt_regs *regs)
{
<------>int i;
<------>int in_kernel = 1;
<------>unsigned long esp;
 
<------>esp = (unsigned long)(regs->sp);
<------>if (user_mode(regs))
<------><------>in_kernel = 0;
 
<------>printk("CPU #: %d\n"
<------>       "   PC: %08lx    SR: %08lx    SP: %08lx\n",
<------>       smp_processor_id(), regs->pc, regs->sr, regs->sp);
<------>printk("GPR00: %08lx GPR01: %08lx GPR02: %08lx GPR03: %08lx\n",
<------>       0L, regs->gpr[1], regs->gpr[2], regs->gpr[3]);
<------>printk("GPR04: %08lx GPR05: %08lx GPR06: %08lx GPR07: %08lx\n",
<------>       regs->gpr[4], regs->gpr[5], regs->gpr[6], regs->gpr[7]);
<------>printk("GPR08: %08lx GPR09: %08lx GPR10: %08lx GPR11: %08lx\n",
<------>       regs->gpr[8], regs->gpr[9], regs->gpr[10], regs->gpr[11]);
<------>printk("GPR12: %08lx GPR13: %08lx GPR14: %08lx GPR15: %08lx\n",
<------>       regs->gpr[12], regs->gpr[13], regs->gpr[14], regs->gpr[15]);
<------>printk("GPR16: %08lx GPR17: %08lx GPR18: %08lx GPR19: %08lx\n",
<------>       regs->gpr[16], regs->gpr[17], regs->gpr[18], regs->gpr[19]);
<------>printk("GPR20: %08lx GPR21: %08lx GPR22: %08lx GPR23: %08lx\n",
<------>       regs->gpr[20], regs->gpr[21], regs->gpr[22], regs->gpr[23]);
<------>printk("GPR24: %08lx GPR25: %08lx GPR26: %08lx GPR27: %08lx\n",
<------>       regs->gpr[24], regs->gpr[25], regs->gpr[26], regs->gpr[27]);
<------>printk("GPR28: %08lx GPR29: %08lx GPR30: %08lx GPR31: %08lx\n",
<------>       regs->gpr[28], regs->gpr[29], regs->gpr[30], regs->gpr[31]);
<------>printk("  RES: %08lx oGPR11: %08lx\n",
<------>       regs->gpr[11], regs->orig_gpr11);
 
<------>printk("Process %s (pid: %d, stackpage=%08lx)\n",
<------>       current->comm, current->pid, (unsigned long)current);
<------>/*
<------> * When in-kernel, we also print out the stack and code at the
<------> * time of the fault..
<------> */
<------>if (in_kernel) {
 
<------><------>printk("\nStack: ");
<------><------>show_stack(NULL, (unsigned long *)esp, KERN_EMERG);
 
<------><------>printk("\nCode: ");
<------><------>if (regs->pc < PAGE_OFFSET)
<------><------><------>goto bad;
 
<------><------>for (i = -24; i < 24; i++) {
<------><------><------>unsigned char c;
<------><------><------>if (__get_user(c, &((unsigned char *)regs->pc)[i])) {
bad:
<------><------><------><------>printk(" Bad PC value.");
<------><------><------><------>break;
<------><------><------>}
 
<------><------><------>if (i == 0)
<------><------><------><------>printk("(%02x) ", c);
<------><------><------>else
<------><------><------><------>printk("%02x ", c);
<------><------>}
<------>}
<------>printk("\n");
}
 
void nommu_dump_state(struct pt_regs *regs,
<------><------>      unsigned long ea, unsigned long vector)
{
<------>int i;
<------>unsigned long addr, stack = regs->sp;
 
<------>printk("\n\r[nommu_dump_state] :: ea %lx, vector %lx\n\r", ea, vector);
 
<------>printk("CPU #: %d\n"
<------>       "   PC: %08lx    SR: %08lx    SP: %08lx\n",
<------>       0, regs->pc, regs->sr, regs->sp);
<------>printk("GPR00: %08lx GPR01: %08lx GPR02: %08lx GPR03: %08lx\n",
<------>       0L, regs->gpr[1], regs->gpr[2], regs->gpr[3]);
<------>printk("GPR04: %08lx GPR05: %08lx GPR06: %08lx GPR07: %08lx\n",
<------>       regs->gpr[4], regs->gpr[5], regs->gpr[6], regs->gpr[7]);
<------>printk("GPR08: %08lx GPR09: %08lx GPR10: %08lx GPR11: %08lx\n",
<------>       regs->gpr[8], regs->gpr[9], regs->gpr[10], regs->gpr[11]);
<------>printk("GPR12: %08lx GPR13: %08lx GPR14: %08lx GPR15: %08lx\n",
<------>       regs->gpr[12], regs->gpr[13], regs->gpr[14], regs->gpr[15]);
<------>printk("GPR16: %08lx GPR17: %08lx GPR18: %08lx GPR19: %08lx\n",
<------>       regs->gpr[16], regs->gpr[17], regs->gpr[18], regs->gpr[19]);
<------>printk("GPR20: %08lx GPR21: %08lx GPR22: %08lx GPR23: %08lx\n",
<------>       regs->gpr[20], regs->gpr[21], regs->gpr[22], regs->gpr[23]);
<------>printk("GPR24: %08lx GPR25: %08lx GPR26: %08lx GPR27: %08lx\n",
<------>       regs->gpr[24], regs->gpr[25], regs->gpr[26], regs->gpr[27]);
<------>printk("GPR28: %08lx GPR29: %08lx GPR30: %08lx GPR31: %08lx\n",
<------>       regs->gpr[28], regs->gpr[29], regs->gpr[30], regs->gpr[31]);
<------>printk("  RES: %08lx oGPR11: %08lx\n",
<------>       regs->gpr[11], regs->orig_gpr11);
 
<------>printk("Process %s (pid: %d, stackpage=%08lx)\n",
<------>       ((struct task_struct *)(__pa(current)))->comm,
<------>       ((struct task_struct *)(__pa(current)))->pid,
<------>       (unsigned long)current);
 
<------>printk("\nStack: ");
<------>printk("Stack dump [0x%08lx]:\n", (unsigned long)stack);
<------>for (i = 0; i < kstack_depth_to_print; i++) {
<------><------>if (((long)stack & (THREAD_SIZE - 1)) == 0)
<------><------><------>break;
<------><------>stack++;
 
<------><------>printk("%lx :: sp + %02d: 0x%08lx\n", stack, i * 4,
<------><------>       *((unsigned long *)(__pa(stack))));
<------>}
<------>printk("\n");
 
<------>printk("Call Trace:   ");
<------>i = 1;
<------>while (((long)stack & (THREAD_SIZE - 1)) != 0) {
<------><------>addr = *((unsigned long *)__pa(stack));
<------><------>stack++;
 
<------><------>if (kernel_text_address(addr)) {
<------><------><------>if (i && ((i % 6) == 0))
<------><------><------><------>printk("\n ");
<------><------><------>printk(" [<%08lx>]", addr);
<------><------><------>i++;
<------><------>}
<------>}
<------>printk("\n");
 
<------>printk("\nCode: ");
 
<------>for (i = -24; i < 24; i++) {
<------><------>unsigned char c;
<------><------>c = ((unsigned char *)(__pa(regs->pc)))[i];
 
<------><------>if (i == 0)
<------><------><------>printk("(%02x) ", c);
<------><------>else
<------><------><------>printk("%02x ", c);
<------>}
<------>printk("\n");
}
 
/* This is normally the 'Oops' routine */
void die(const char *str, struct pt_regs *regs, long err)
{
 
<------>console_verbose();
<------>printk("\n%s#: %04lx\n", str, err & 0xffff);
<------>show_registers(regs);
#ifdef CONFIG_JUMP_UPON_UNHANDLED_EXCEPTION
<------>printk("\n\nUNHANDLED_EXCEPTION: entering infinite loop\n");
 
<------>/* shut down interrupts */
<------>local_irq_disable();
 
<------>__asm__ __volatile__("l.nop   1");
<------>do {} while (1);
#endif
<------>do_exit(SIGSEGV);
}
 
/* This is normally the 'Oops' routine */
void die_if_kernel(const char *str, struct pt_regs *regs, long err)
{
<------>if (user_mode(regs))
<------><------>return;
 
<------>die(str, regs, err);
}
 
void unhandled_exception(struct pt_regs *regs, int ea, int vector)
{
<------>printk("Unable to handle exception at EA =0x%x, vector 0x%x",
<------>       ea, vector);
<------>die("Oops", regs, 9);
}
 
void __init trap_init(void)
{
<------>/* Nothing needs to be done */
}
 
asmlinkage void do_trap(struct pt_regs *regs, unsigned long address)
{
<------>force_sig_fault(SIGTRAP, TRAP_TRACE, (void __user *)address);
 
<------>regs->pc += 4;
}
 
asmlinkage void do_unaligned_access(struct pt_regs *regs, unsigned long address)
{
<------>if (user_mode(regs)) {
<------><------>/* Send a SIGBUS */
<------><------>force_sig_fault(SIGBUS, BUS_ADRALN, (void __user *)address);
<------>} else {
<------><------>printk("KERNEL: Unaligned Access 0x%.8lx\n", address);
<------><------>show_registers(regs);
<------><------>die("Die:", regs, address);
<------>}
 
}
 
asmlinkage void do_bus_fault(struct pt_regs *regs, unsigned long address)
{
<------>if (user_mode(regs)) {
<------><------>/* Send a SIGBUS */
<------><------>force_sig_fault(SIGBUS, BUS_ADRERR, (void __user *)address);
<------>} else {		/* Kernel mode */
<------><------>printk("KERNEL: Bus error (SIGBUS) 0x%.8lx\n", address);
<------><------>show_registers(regs);
<------><------>die("Die:", regs, address);
<------>}
}
 
static inline int in_delay_slot(struct pt_regs *regs)
{
#ifdef CONFIG_OPENRISC_NO_SPR_SR_DSX
<------>/* No delay slot flag, do the old way */
<------>unsigned int op, insn;
 
<------>insn = *((unsigned int *)regs->pc);
<------>op = insn >> 26;
<------>switch (op) {
<------>case 0x00: /* l.j */
<------>case 0x01: /* l.jal */
<------>case 0x03: /* l.bnf */
<------>case 0x04: /* l.bf */
<------>case 0x11: /* l.jr */
<------>case 0x12: /* l.jalr */
<------><------>return 1;
<------>default:
<------><------>return 0;
<------>}
#else
<------>return mfspr(SPR_SR) & SPR_SR_DSX;
#endif
}
 
static inline void adjust_pc(struct pt_regs *regs, unsigned long address)
{
<------>int displacement;
<------>unsigned int rb, op, jmp;
 
<------>if (unlikely(in_delay_slot(regs))) {
<------><------>/* In delay slot, instruction at pc is a branch, simulate it */
<------><------>jmp = *((unsigned int *)regs->pc);
 
<------><------>displacement = sign_extend32(((jmp) & 0x3ffffff) << 2, 27);
<------><------>rb = (jmp & 0x0000ffff) >> 11;
<------><------>op = jmp >> 26;
 
<------><------>switch (op) {
<------><------>case 0x00: /* l.j */
<------><------><------>regs->pc += displacement;
<------><------><------>return;
<------><------>case 0x01: /* l.jal */
<------><------><------>regs->pc += displacement;
<------><------><------>regs->gpr[9] = regs->pc + 8;
<------><------><------>return;
<------><------>case 0x03: /* l.bnf */
<------><------><------>if (regs->sr & SPR_SR_F)
<------><------><------><------>regs->pc += 8;
<------><------><------>else
<------><------><------><------>regs->pc += displacement;
<------><------><------>return;
<------><------>case 0x04: /* l.bf */
<------><------><------>if (regs->sr & SPR_SR_F)
<------><------><------><------>regs->pc += displacement;
<------><------><------>else
<------><------><------><------>regs->pc += 8;
<------><------><------>return;
<------><------>case 0x11: /* l.jr */
<------><------><------>regs->pc = regs->gpr[rb];
<------><------><------>return;
<------><------>case 0x12: /* l.jalr */
<------><------><------>regs->pc = regs->gpr[rb];
<------><------><------>regs->gpr[9] = regs->pc + 8;
<------><------><------>return;
<------><------>default:
<------><------><------>break;
<------><------>}
<------>} else {
<------><------>regs->pc += 4;
<------>}
}
 
static inline void simulate_lwa(struct pt_regs *regs, unsigned long address,
<------><------><------><------>unsigned int insn)
{
<------>unsigned int ra, rd;
<------>unsigned long value;
<------>unsigned long orig_pc;
<------>long imm;
 
<------>const struct exception_table_entry *entry;
 
<------>orig_pc = regs->pc;
<------>adjust_pc(regs, address);
 
<------>ra = (insn >> 16) & 0x1f;
<------>rd = (insn >> 21) & 0x1f;
<------>imm = (short)insn;
<------>lwa_addr = (unsigned long __user *)(regs->gpr[ra] + imm);
 
<------>if ((unsigned long)lwa_addr & 0x3) {
<------><------>do_unaligned_access(regs, address);
<------><------>return;
<------>}
 
<------>if (get_user(value, lwa_addr)) {
<------><------>if (user_mode(regs)) {
<------><------><------>force_sig(SIGSEGV);
<------><------><------>return;
<------><------>}
 
<------><------>if ((entry = search_exception_tables(orig_pc))) {
<------><------><------>regs->pc = entry->fixup;
<------><------><------>return;
<------><------>}
 
<------><------>/* kernel access in kernel space, load it directly */
<------><------>value = *((unsigned long *)lwa_addr);
<------>}
 
<------>lwa_flag = 1;
<------>regs->gpr[rd] = value;
}
 
static inline void simulate_swa(struct pt_regs *regs, unsigned long address,
<------><------><------><------>unsigned int insn)
{
<------>unsigned long __user *vaddr;
<------>unsigned long orig_pc;
<------>unsigned int ra, rb;
<------>long imm;
 
<------>const struct exception_table_entry *entry;
 
<------>orig_pc = regs->pc;
<------>adjust_pc(regs, address);
 
<------>ra = (insn >> 16) & 0x1f;
<------>rb = (insn >> 11) & 0x1f;
<------>imm = (short)(((insn & 0x2200000) >> 10) | (insn & 0x7ff));
<------>vaddr = (unsigned long __user *)(regs->gpr[ra] + imm);
 
<------>if (!lwa_flag || vaddr != lwa_addr) {
<------><------>regs->sr &= ~SPR_SR_F;
<------><------>return;
<------>}
 
<------>if ((unsigned long)vaddr & 0x3) {
<------><------>do_unaligned_access(regs, address);
<------><------>return;
<------>}
 
<------>if (put_user(regs->gpr[rb], vaddr)) {
<------><------>if (user_mode(regs)) {
<------><------><------>force_sig(SIGSEGV);
<------><------><------>return;
<------><------>}
 
<------><------>if ((entry = search_exception_tables(orig_pc))) {
<------><------><------>regs->pc = entry->fixup;
<------><------><------>return;
<------><------>}
 
<------><------>/* kernel access in kernel space, store it directly */
<------><------>*((unsigned long *)vaddr) = regs->gpr[rb];
<------>}
 
<------>lwa_flag = 0;
<------>regs->sr |= SPR_SR_F;
}
 
#define INSN_LWA	0x1b
#define INSN_SWA	0x33
 
asmlinkage void do_illegal_instruction(struct pt_regs *regs,
<------><------><------><------>       unsigned long address)
{
<------>unsigned int op;
<------>unsigned int insn = *((unsigned int *)address);
 
<------>op = insn >> 26;
 
<------>switch (op) {
<------>case INSN_LWA:
<------><------>simulate_lwa(regs, address, insn);
<------><------>return;
 
<------>case INSN_SWA:
<------><------>simulate_swa(regs, address, insn);
<------><------>return;
 
<------>default:
<------><------>break;
<------>}
 
<------>if (user_mode(regs)) {
<------><------>/* Send a SIGILL */
<------><------>force_sig_fault(SIGILL, ILL_ILLOPC, (void __user *)address);
<------>} else {		/* Kernel mode */
<------><------>printk("KERNEL: Illegal instruction (SIGILL) 0x%.8lx\n",
<------><------>       address);
<------><------>show_registers(regs);
<------><------>die("Die:", regs, address);
<------>}
}