/*      $OpenBSD: db_interface.c,v 1.40 2025/02/12 20:18:31 bluhm Exp $ */
/*      $NetBSD: db_interface.c,v 1.1 2003/04/26 18:39:27 fvdl Exp $    */

/*
 * Mach Operating System
 * Copyright (c) 1991,1990 Carnegie Mellon University
 * All Rights Reserved.
 *
 * Permission to use, copy, modify and distribute this software and its
 * documentation is hereby granted, provided that both the copyright
 * notice and this permission notice appear in all copies of the
 * software, derivative works or modified versions, and any portions
 * thereof, and that both notices appear in supporting documentation.
 *
 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
 * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
 *
 * Carnegie Mellon requests users of this software to return to
 *
 *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
 *  School of Computer Science
 *  Carnegie Mellon University
 *  Pittsburgh PA 15213-3890
 *
 * any improvements or extensions that they make and grant Carnegie the
 * rights to redistribute these changes.
 *
 *      db_interface.c,v 2.4 1991/02/05 17:11:13 mrt (CMU)
 */

/*
 * Interface to new debugger.
 */

#include <sys/param.h>
#include <sys/reboot.h>
#include <sys/systm.h>
#include <sys/mutex.h>

#include <uvm/uvm_extern.h>

#include <dev/cons.h>

#include <machine/cpufunc.h>
#include <machine/db_machdep.h>
#include <machine/cpuvar.h>
#include <machine/i82093var.h>
#include <machine/atomic.h>
#include <machine/specialreg.h>
#include <machine/segments.h>

#include <ddb/db_sym.h>
#include <ddb/db_command.h>
#include <ddb/db_extern.h>
#include <ddb/db_output.h>
#include <ddb/db_run.h>
#include <ddb/db_var.h>

#include "acpi.h"
#if NACPI > 0
#include <dev/acpi/acpidebug.h>
#endif /* NACPI > 0 */

#include "wsdisplay.h"
#if NWSDISPLAY > 0
#include <dev/wscons/wsdisplayvar.h>
#endif

extern label_t *db_recover;
extern const char * const trap_type[];
extern const int trap_types;

#ifdef MULTIPROCESSOR
struct db_mutex ddb_mp_mutex = DB_MUTEX_INITIALIZER;
volatile int ddb_state = DDB_STATE_NOT_RUNNING;
volatile cpuid_t ddb_active_cpu;
int              db_switch_cpu;
long             db_switch_to_cpu;
#endif

db_regs_t ddb_regs;

void db_printtrap(int, int);
#ifdef MULTIPROCESSOR
void db_cpuinfo_cmd(db_expr_t, int, db_expr_t, char *);
void db_startproc_cmd(db_expr_t, int, db_expr_t, char *);
void db_stopproc_cmd(db_expr_t, int, db_expr_t, char *);
void db_ddbproc_cmd(db_expr_t, int, db_expr_t, char *);
#endif

/*
 * Print trap reason.
 */
void
db_printtrap(int type, int code)
{
        db_printf("kernel: ");
        if (type >= trap_types || type < 0)
                db_printf("type %d", type);
        else
                db_printf("%s", trap_type[type]);
        db_printf(" trap, code=%x\n", code);
}

/*
 *  db_ktrap - field a TRACE or BPT trap
 */
int
db_ktrap(int type, int code, db_regs_t *regs)
{
        int s;

#if NWSDISPLAY > 0
        wsdisplay_enter_ddb();
#endif

        switch (type) {
        case T_BPTFLT:  /* breakpoint */
        case T_TRCTRAP: /* single_step */
        case T_NMI:     /* NMI */
        case -1:        /* keyboard interrupt */
                break;
        default:
                if (!db_panic)
                        return (0);

                db_printtrap(type, code);
                if (db_recover != 0) {
                        db_error("Faulted in DDB; continuing...\n");
                        /*NOTREACHED*/
                }
        }

#ifdef MULTIPROCESSOR
        db_mtx_enter(&ddb_mp_mutex);
        if (ddb_state == DDB_STATE_EXITING)
                ddb_state = DDB_STATE_NOT_RUNNING;
        db_mtx_leave(&ddb_mp_mutex);
        while (db_enter_ddb()) {
#endif

        ddb_regs = *regs;

        ddb_regs.tf_cs &= 0xffff;
        ddb_regs.tf_ss &= 0xffff;

        s = splhigh();
        db_active++;
        cnpollc(1);
        db_trap(type, code);
        cnpollc(0);
        db_active--;
        splx(s);

        *regs = ddb_regs;

#ifdef MULTIPROCESSOR
                if (!db_switch_cpu)
                        ddb_state = DDB_STATE_EXITING;
        }
#endif
        return (1);
}

void
db_sysregs_cmd(db_expr_t addr, int have_addr, db_expr_t count, char *modif)
{
        struct region_descriptor idtr, gdtr;
        uint64_t cr;
        uint16_t ldtr, tr;
        uint64_t gsb;

        __asm__ volatile("sidt %0" : "=m" (idtr));
        db_printf("idtr:   0x%08llx/%04x\n", idtr.rd_base, idtr.rd_limit);

        __asm__ volatile("sgdt %0" : "=m" (gdtr));
        db_printf("gdtr:   0x%08llx/%04x\n", gdtr.rd_base, gdtr.rd_limit);

        __asm__ volatile("sldt %0" : "=g" (ldtr));
        db_printf("ldtr:   0x%04x\n", ldtr);

        __asm__ volatile("str %0" : "=g" (tr));
        db_printf("tr:     0x%04x\n", tr);

        __asm__ volatile("movq %%cr0,%0" : "=r" (cr));
        db_printf("cr0:    0x%016llx\n", cr);

        __asm__ volatile("movq %%cr2,%0" : "=r" (cr));
        db_printf("cr2:    0x%016llx\n", cr);

        __asm__ volatile("movq %%cr3,%0" : "=r" (cr));
        db_printf("cr3:    0x%016llx\n", cr);

        __asm__ volatile("movq %%cr4,%0" : "=r" (cr));
        db_printf("cr4:    0x%016llx\n", cr);

        gsb = rdmsr(MSR_GSBASE);
        db_printf("gsb:    0x%016llx\n", gsb);

        gsb = rdmsr(MSR_KERNELGSBASE);
        db_printf("kgsb:   0x%016llx\n", gsb);
}


#ifdef MULTIPROCESSOR
void
db_cpuinfo_cmd(db_expr_t addr, int have_addr, db_expr_t count, char *modif)
{
        int i;

        for (i = 0; i < MAXCPUS; i++) {
                if (cpu_info[i] != NULL) {
                        db_printf("%c%4d: ", (i == cpu_number()) ? '*' : ' ',
                            CPU_INFO_UNIT(cpu_info[i]));
                        switch(cpu_info[i]->ci_ddb_paused) {
                        case CI_DDB_RUNNING:
                                db_printf("running\n");
                                break;
                        case CI_DDB_SHOULDSTOP:
                                db_printf("stopping\n");
                                break;
                        case CI_DDB_STOPPED:
                                db_printf("stopped\n");
                                break;
                        case CI_DDB_ENTERDDB:
                                db_printf("entering ddb\n");
                                break;
                        case CI_DDB_INDDB:
                                db_printf("ddb\n");
                                break;
                        default:
                                db_printf("? (%d)\n",
                                    cpu_info[i]->ci_ddb_paused);
                                break;
                        }
                }
        }
}

void
db_startproc_cmd(db_expr_t addr, int have_addr, db_expr_t count, char *modif)
{
        int i;

        if (have_addr) {
                if (addr >= 0 && addr < MAXCPUS &&
                    cpu_info[addr] != NULL && addr != cpu_number())
                        db_startcpu(addr);
                else
                        db_printf("Invalid cpu %d\n", (int)addr);
        } else {
                for (i = 0; i < MAXCPUS; i++) {
                        if (cpu_info[i] != NULL && i != cpu_number())
                                db_startcpu(i);
                }
        }
}

void
db_stopproc_cmd(db_expr_t addr, int have_addr, db_expr_t count, char *modif)
{
        int i;

        if (have_addr) {
                if (addr >= 0 && addr < MAXCPUS &&
                    cpu_info[addr] != NULL && addr != cpu_number())
                        db_stopcpu(addr);
                else
                        db_printf("Invalid cpu %d\n", (int)addr);
        } else {
                for (i = 0; i < MAXCPUS; i++) {
                        if (cpu_info[i] != NULL && i != cpu_number())
                                db_stopcpu(i);
                }
        }
}

void
db_ddbproc_cmd(db_expr_t addr, int have_addr, db_expr_t count, char *modif)
{
        if (have_addr) {
                if (addr >= 0 && addr < MAXCPUS &&
                    cpu_info[addr] != NULL && addr != cpu_number()) {
                        db_stopcpu(addr);
                        db_switch_to_cpu = addr;
                        db_switch_cpu = 1;
                        db_cmd_loop_done = 1;
                } else {
                        db_printf("Invalid cpu %d\n", (int)addr);
                }
        } else {
                db_printf("CPU not specified\n");
        }
}

int
db_enter_ddb(void)
{
        int i;

        db_mtx_enter(&ddb_mp_mutex);

        /* If we are first in, grab ddb and stop all other CPUs */
        if (ddb_state == DDB_STATE_NOT_RUNNING) {
                ddb_active_cpu = cpu_number();
                ddb_state = DDB_STATE_RUNNING;
                curcpu()->ci_ddb_paused = CI_DDB_INDDB;
                db_mtx_leave(&ddb_mp_mutex);
                for (i = 0; i < MAXCPUS; i++) {
                        if (cpu_info[i] != NULL && i != cpu_number() &&
                            cpu_info[i]->ci_ddb_paused != CI_DDB_STOPPED) {
                                cpu_info[i]->ci_ddb_paused = CI_DDB_SHOULDSTOP;
                                x86_send_ipi(cpu_info[i], X86_IPI_DDB);
                        }
                }
                return (1);
        }

        /* Leaving ddb completely.  Start all other CPUs and return 0 */
        if (ddb_active_cpu == cpu_number() && ddb_state == DDB_STATE_EXITING) {
                for (i = 0; i < MAXCPUS; i++) {
                        if (cpu_info[i] != NULL) {
                                cpu_info[i]->ci_ddb_paused = CI_DDB_RUNNING;
                        }
                }
                db_mtx_leave(&ddb_mp_mutex);
                return (0);
        }

        /* We're switching to another CPU.  db_ddbproc_cmd() has made sure
         * it is waiting for ddb, we just have to set ddb_active_cpu. */
        if (ddb_active_cpu == cpu_number() && db_switch_cpu) {
                curcpu()->ci_ddb_paused = CI_DDB_SHOULDSTOP;
                db_switch_cpu = 0;
                ddb_active_cpu = db_switch_to_cpu;
                cpu_info[db_switch_to_cpu]->ci_ddb_paused = CI_DDB_ENTERDDB;
        }

        /* Wait until we should enter ddb or resume */
        while (ddb_active_cpu != cpu_number() &&
            curcpu()->ci_ddb_paused != CI_DDB_RUNNING) {
                if (curcpu()->ci_ddb_paused == CI_DDB_SHOULDSTOP)
                        curcpu()->ci_ddb_paused = CI_DDB_STOPPED;
                db_mtx_leave(&ddb_mp_mutex);

                /* Busy wait without locking, we'll confirm with lock later */
                while (ddb_active_cpu != cpu_number() &&
                    curcpu()->ci_ddb_paused != CI_DDB_RUNNING)
                        CPU_BUSY_CYCLE();

                db_mtx_enter(&ddb_mp_mutex);
        }

        /* Either enter ddb or exit */
        if (ddb_active_cpu == cpu_number() && ddb_state == DDB_STATE_RUNNING) {
                curcpu()->ci_ddb_paused = CI_DDB_INDDB;
                db_mtx_leave(&ddb_mp_mutex);
                return (1);
        } else {
                db_mtx_leave(&ddb_mp_mutex);
                return (0);
        }
}

void
db_startcpu(int cpu)
{
        if (cpu != cpu_number() && cpu_info[cpu] != NULL) {
                db_mtx_enter(&ddb_mp_mutex);
                cpu_info[cpu]->ci_ddb_paused = CI_DDB_RUNNING;
                db_mtx_leave(&ddb_mp_mutex);
        }
}

void
db_stopcpu(int cpu)
{
        db_mtx_enter(&ddb_mp_mutex);
        if (cpu != cpu_number() && cpu_info[cpu] != NULL &&
            cpu_info[cpu]->ci_ddb_paused != CI_DDB_STOPPED) {
                cpu_info[cpu]->ci_ddb_paused = CI_DDB_SHOULDSTOP;
                db_mtx_leave(&ddb_mp_mutex);
                x86_send_ipi(cpu_info[cpu], X86_IPI_DDB);
        } else {
                db_mtx_leave(&ddb_mp_mutex);
        }
}

void
x86_ipi_db(struct cpu_info *ci)
{
        db_enter();
}
#endif /* MULTIPROCESSOR */

#if NACPI > 0
const struct db_command db_acpi_cmds[] = {
        { "disasm",     db_acpi_disasm,         CS_OWN, NULL },
        { "showval",    db_acpi_showval,        CS_OWN, NULL },
        { "tree",       db_acpi_tree,           0,      NULL },
        { "trace",      db_acpi_trace,          0,      NULL },
        { NULL,         NULL,                   0,      NULL }
};
#endif /* NACPI > 0 */

const struct db_command db_machine_command_table[] = {
#ifdef MULTIPROCESSOR
        { "cpuinfo",    db_cpuinfo_cmd,         0,      0 },
        { "startcpu",   db_startproc_cmd,       0,      0 },
        { "stopcpu",    db_stopproc_cmd,        0,      0 },
        { "ddbcpu",     db_ddbproc_cmd,         0,      0 },
#endif
        { "sysregs",    db_sysregs_cmd,         0,      0 },
#if NACPI > 0
        { "acpi",       NULL,                   0,      db_acpi_cmds },
#endif /* NACPI > 0 */
        { NULL, },
};

void
db_machine_init(void)
{
#ifdef MULTIPROCESSOR
        int i;

        for (i = 0; i < MAXCPUS; i++) {
                if (cpu_info[i] != NULL)
                        cpu_info[i]->ci_ddb_paused = CI_DDB_RUNNING;
        }
#endif
}

void
db_enter(void)
{
        breakpoint();
}