Orange Pi5 kernel

/*
 * Created by: Jason Wessel <jason.wessel@windriver.com>
 *
 * Copyright (c) 2009 Wind River Systems, Inc.  All Rights Reserved.
 *
 * This file is licensed under the terms of the GNU General Public
 * License version 2. This program is licensed "as is" without any
 * warranty of any kind, whether express or implied.
 */
 
#include <linux/kgdb.h>
#include <linux/kdb.h>
#include <linux/kdebug.h>
#include <linux/export.h>
#include <linux/hardirq.h>
#include "kdb_private.h"
#include "../debug_core.h"
 
/*
 * KDB interface to KGDB internals
 */
get_char_func kdb_poll_funcs[] = {
<------>dbg_io_get_char,
<------>NULL,
<------>NULL,
<------>NULL,
<------>NULL,
<------>NULL,
};
EXPORT_SYMBOL_GPL(kdb_poll_funcs);
 
int kdb_poll_idx = 1;
EXPORT_SYMBOL_GPL(kdb_poll_idx);
 
static struct kgdb_state *kdb_ks;
 
int kdb_common_init_state(struct kgdb_state *ks)
{
<------>kdb_initial_cpu = atomic_read(&kgdb_active);
<------>kdb_current_task = kgdb_info[ks->cpu].task;
<------>kdb_current_regs = kgdb_info[ks->cpu].debuggerinfo;
<------>return 0;
}
 
int kdb_common_deinit_state(void)
{
<------>kdb_initial_cpu = -1;
<------>kdb_current_task = NULL;
<------>kdb_current_regs = NULL;
<------>return 0;
}
 
int kdb_stub(struct kgdb_state *ks)
{
<------>int error = 0;
<------>kdb_bp_t *bp;
<------>unsigned long addr = kgdb_arch_pc(ks->ex_vector, ks->linux_regs);
<------>kdb_reason_t reason = KDB_REASON_OOPS;
<------>kdb_dbtrap_t db_result = KDB_DB_NOBPT;
<------>int i;
 
<------>kdb_ks = ks;
<------>if (KDB_STATE(REENTRY)) {
<------><------>reason = KDB_REASON_SWITCH;
<------><------>KDB_STATE_CLEAR(REENTRY);
<------><------>addr = instruction_pointer(ks->linux_regs);
<------>}
<------>ks->pass_exception = 0;
<------>if (atomic_read(&kgdb_setting_breakpoint))
<------><------>reason = KDB_REASON_KEYBOARD;
 
<------>if (ks->err_code == KDB_REASON_SYSTEM_NMI && ks->signo == SIGTRAP)
<------><------>reason = KDB_REASON_SYSTEM_NMI;
 
<------>else if (in_nmi())
<------><------>reason = KDB_REASON_NMI;
 
<------>for (i = 0, bp = kdb_breakpoints; i < KDB_MAXBPT; i++, bp++) {
<------><------>if ((bp->bp_enabled) && (bp->bp_addr == addr)) {
<------><------><------>reason = KDB_REASON_BREAK;
<------><------><------>db_result = KDB_DB_BPT;
<------><------><------>if (addr != instruction_pointer(ks->linux_regs))
<------><------><------><------>kgdb_arch_set_pc(ks->linux_regs, addr);
<------><------><------>break;
<------><------>}
<------>}
<------>if (reason == KDB_REASON_BREAK || reason == KDB_REASON_SWITCH) {
<------><------>for (i = 0, bp = kdb_breakpoints; i < KDB_MAXBPT; i++, bp++) {
<------><------><------>if (bp->bp_free)
<------><------><------><------>continue;
<------><------><------>if (bp->bp_addr == addr) {
<------><------><------><------>bp->bp_delay = 1;
<------><------><------><------>bp->bp_delayed = 1;
<------>/*
<------> * SSBPT is set when the kernel debugger must single step a
<------> * task in order to re-establish an instruction breakpoint
<------> * which uses the instruction replacement mechanism.  It is
<------> * cleared by any action that removes the need to single-step
<------> * the breakpoint.
<------> */
<------><------><------><------>reason = KDB_REASON_BREAK;
<------><------><------><------>db_result = KDB_DB_BPT;
<------><------><------><------>KDB_STATE_SET(SSBPT);
<------><------><------><------>break;
<------><------><------>}
<------><------>}
<------>}
 
<------>if (reason != KDB_REASON_BREAK && ks->ex_vector == 0 &&
<------><------>ks->signo == SIGTRAP) {
<------><------>reason = KDB_REASON_SSTEP;
<------><------>db_result = KDB_DB_BPT;
<------>}
<------>/* Set initial kdb state variables */
<------>KDB_STATE_CLEAR(KGDB_TRANS);
<------>kdb_common_init_state(ks);
<------>/* Remove any breakpoints as needed by kdb and clear single step */
<------>kdb_bp_remove();
<------>KDB_STATE_CLEAR(DOING_SS);
<------>KDB_STATE_SET(PAGER);
<------>if (ks->err_code == DIE_OOPS || reason == KDB_REASON_OOPS) {
<------><------>ks->pass_exception = 1;
<------><------>KDB_FLAG_SET(CATASTROPHIC);
<------>}
<------>/* set CATASTROPHIC if the system contains unresponsive processors */
<------>for_each_online_cpu(i)
<------><------>if (!kgdb_info[i].enter_kgdb)
<------><------><------>KDB_FLAG_SET(CATASTROPHIC);
<------>if (KDB_STATE(SSBPT) && reason == KDB_REASON_SSTEP) {
<------><------>KDB_STATE_CLEAR(SSBPT);
<------><------>KDB_STATE_CLEAR(DOING_SS);
<------>} else {
<------><------>/* Start kdb main loop */
<------><------>error = kdb_main_loop(KDB_REASON_ENTER, reason,
<------><------><------><------>      ks->err_code, db_result, ks->linux_regs);
<------>}
<------>/*
<------> * Upon exit from the kdb main loop setup break points and restart
<------> * the system based on the requested continue state
<------> */
<------>kdb_common_deinit_state();
<------>KDB_STATE_CLEAR(PAGER);
<------>kdbnearsym_cleanup();
<------>if (error == KDB_CMD_KGDB) {
<------><------>if (KDB_STATE(DOING_KGDB))
<------><------><------>KDB_STATE_CLEAR(DOING_KGDB);
<------><------>return DBG_PASS_EVENT;
<------>}
<------>kdb_bp_install(ks->linux_regs);
<------>/* Set the exit state to a single step or a continue */
<------>if (KDB_STATE(DOING_SS))
<------><------>gdbstub_state(ks, "s");
<------>else
<------><------>gdbstub_state(ks, "c");
 
<------>KDB_FLAG_CLEAR(CATASTROPHIC);
 
<------>/* Invoke arch specific exception handling prior to system resume */
<------>kgdb_info[ks->cpu].ret_state = gdbstub_state(ks, "e");
<------>if (ks->pass_exception)
<------><------>kgdb_info[ks->cpu].ret_state = 1;
<------>if (error == KDB_CMD_CPU) {
<------><------>KDB_STATE_SET(REENTRY);
<------><------>/*
<------><------> * Force clear the single step bit because kdb emulates this
<------><------> * differently vs the gdbstub
<------><------> */
<------><------>kgdb_single_step = 0;
<------><------>return DBG_SWITCH_CPU_EVENT;
<------>}
<------>return kgdb_info[ks->cpu].ret_state;
}
 
void kdb_gdb_state_pass(char *buf)
{
<------>gdbstub_state(kdb_ks, buf);
}