/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 *
 * Copyright 2018 Joyent, Inc.
 * Copyright 2025 Oxide Computer Company
 */

/*
 * isa-dependent portions of the kmdb target
 */

#include <kmdb/kvm.h>
#include <kmdb/kmdb_kdi.h>
#include <kmdb/kmdb_asmutil.h>
#include <mdb/mdb_debug.h>
#include <mdb/mdb_stack.h>
#include <mdb/mdb_err.h>
#include <mdb/mdb_list.h>
#include <mdb/mdb_target_impl.h>
#include <mdb/mdb_isautil.h>
#include <mdb/mdb_kreg_impl.h>
#include <mdb/mdb.h>

#include <sys/types.h>
#include <sys/frame.h>
#include <sys/trap.h>
#include <sys/bitmap.h>
#include <sys/pci_impl.h>

/* Higher than the highest trap number for which we have a defined specifier */
#define KMT_MAXTRAPNO   0x20

#define IOPORTLIMIT     0xffff  /* XXX find a new home for this */

const char *
kmt_def_dismode(void)
{
#ifdef  __amd64
        return ("amd64");
#else
        return ("ia32");
#endif
}

int
kmt_step_out_validate(mdb_tgt_t *t, uintptr_t pc)
{
        kmt_data_t *kmt = t->t_data;
        int i;

        for (i = 0; i < sizeof (kmt->kmt_intrsyms) / sizeof (GElf_Sym); i++) {
                GElf_Sym *sym = (GElf_Sym *)&kmt->kmt_intrsyms + i;

                if (pc >= sym->st_value && pc < sym->st_value + sym->st_size)
                        return (0);
        }

        return (1);
}

/*
 * Determine the return address for the current frame.
 */
int
kmt_step_out(mdb_tgt_t *t, uintptr_t *p)
{
        mdb_instr_t instr;
        kreg_t pc, sp, fp;

        (void) kmdb_dpi_get_register("pc", &pc);
        (void) kmdb_dpi_get_register("sp", &sp);
        (void) kmdb_dpi_get_register("fp", &fp);

        if (mdb_tgt_vread(t, &instr, sizeof (mdb_instr_t), pc) !=
            sizeof (mdb_instr_t))
                return (-1); /* errno is set for us */

        if (!kmt_step_out_validate(t, pc))
                return (set_errno(EMDB_TGTNOTSUP));

        return (mdb_isa_step_out(t, p, pc, fp, sp, instr));
}

/*
 * Return the address of the next instruction following a call, or return -1
 * and set errno to EAGAIN if the target should just single-step.
 */
int
kmt_next(mdb_tgt_t *t, uintptr_t *p)
{
        kreg_t pc;
        mdb_instr_t instr;

        (void) kmdb_dpi_get_register("pc", &pc);

        if (mdb_tgt_vread(t, &instr, sizeof (mdb_instr_t), pc) !=
            sizeof (mdb_instr_t))
                return (-1); /* errno is set for us */

        return (mdb_isa_next(t, p, pc, instr));
}

static int
kmt_stack_common(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv,
    int cpuid, mdb_stack_frame_flags_t sflags, mdb_tgt_stack_f *func)
{
        mdb_tgt_t *t = mdb.m_target;
        const mdb_tgt_gregset_t *grp = NULL;
        mdb_tgt_gregset_t gregs;
        mdb_stack_frame_hdl_t *hdl;
        uint_t arglim = mdb.m_nargs;
        int i;

        if (flags & DCMD_ADDRSPEC) {
                bzero(&gregs, sizeof (gregs));
                gregs.kregs[KREG_FP] = addr;
                grp = &gregs;
        } else {
                grp = kmdb_dpi_get_gregs(cpuid);
        }

        if (grp == NULL) {
                warn("failed to retrieve registers for cpu %d", cpuid);
                return (DCMD_ERR);
        }

        i = mdb_getopts(argc, argv,
            'n', MDB_OPT_SETBITS, MSF_ADDR, &sflags,
            's', MDB_OPT_SETBITS, MSF_SIZES, &sflags,
            't', MDB_OPT_SETBITS, MSF_TYPES, &sflags,
            'v', MDB_OPT_SETBITS, MSF_VERBOSE, &sflags,
            NULL);

        argc -= i;
        argv += i;

        if (argc != 0) {
                if (argv->a_type == MDB_TYPE_CHAR || argc > 1)
                        return (DCMD_USAGE);

                arglim = mdb_argtoull(argv);
        }

        if ((hdl = mdb_stack_frame_init(t, arglim, sflags)) == NULL) {
                mdb_warn("failed to init stack frame\n");
                return (DCMD_ERR);
        }

        (void) mdb_isa_kvm_stack_iter(t, grp, func, (void *)hdl);

        return (DCMD_OK);
}

int
kmt_cpustack(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv,
    int cpuid, uint_t verbose)
{
        return (kmt_stack_common(addr, flags, argc, argv, cpuid,
            verbose != 0 ? MSF_VERBOSE : 0, mdb_isa_kvm_frame));
}

int
kmt_stack(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
{
        return (kmt_stack_common(addr, flags, argc, argv, DPI_MASTER_CPUID,
            0, mdb_isa_kvm_frame));
}

int
kmt_stackv(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
{
        return (kmt_stack_common(addr, flags, argc, argv, DPI_MASTER_CPUID,
            MSF_VERBOSE, mdb_isa_kvm_frame));
}

int
kmt_stackr(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
{
        return (kmt_stack_common(addr, flags, argc, argv, DPI_MASTER_CPUID,
            MSF_VERBOSE, mdb_isa_kvm_frame));
}

/*ARGSUSED*/
void
kmt_printregs(const mdb_tgt_gregset_t *gregs)
{
        mdb_isa_printregs(gregs);
}

#define IOCHECK_NOWARN  0
#define IOCHECK_WARN    1

static int
kmt_io_check(uint64_t nbytes, uintptr_t addr, int dowarn)
{
        if (addr > IOPORTLIMIT) {
                if (dowarn)
                        warn("port address must be 0-%#x\n", IOPORTLIMIT);
                return (set_errno(EINVAL));
        }

        if (nbytes != 1 && nbytes != 2 && nbytes != 4) {
                if (dowarn)
                        warn("port access must be 1, 2, or 4 bytes\n");
                return (set_errno(EINVAL));
        }

        if ((addr & (nbytes - 1)) != 0) {
                if (dowarn) {
                        warn("address for %llu-byte access must be %llu-byte "
                            "aligned\n", (u_longlong_t)nbytes,
                            (u_longlong_t)nbytes);
                }
                return (set_errno(EINVAL));
        }

        return (0);
}

/*ARGSUSED1*/
int
kmt_in_dcmd(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
{
        uint64_t len = 0;
        uint32_t buf;

        if (mdb_getopts(argc, argv,
            'L', MDB_OPT_UINT64, &len,
            NULL) != argc)
                return (DCMD_USAGE);

        if (len == 0)
                len = mdb.m_dcount;

        if (kmt_io_check(len, addr, IOCHECK_WARN) < 0)
                return (DCMD_ERR);

        if (mdb_tgt_ioread(mdb.m_target, &buf, len, addr) < 0) {
                warn("failed to read from port 0x%llx", (u_longlong_t)addr);
                return (DCMD_ERR);
        }

        mdb_printf("%x\n", buf);

        return (DCMD_OK);
}

/*ARGSUSED1*/
int
kmt_out_dcmd(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
{
        uint64_t len = 0;
        uint64_t val;

        if (mdb_getopts(argc, argv,
            'L', MDB_OPT_UINT64, &len,
            NULL) != argc - 1)
                return (DCMD_USAGE);

        if (len == 0)
                len = mdb.m_dcount;

        argv += argc - 1;
        val = mdb_argtoull(argv);

        if (kmt_io_check(len, addr, IOCHECK_WARN) < 0)
                return (DCMD_ERR);

        if (val > (1ULL << (len * NBBY)) - 1) {
                warn("value is out of range for port size\n");
                return (DCMD_ERR);
        }

        if (mdb_tgt_iowrite(mdb.m_target, &val, len, addr) < 0) {
                warn("failed to write to port %llx", (u_longlong_t)addr);
                return (DCMD_ERR);
        }

        return (DCMD_OK);
}

static int
kmt_rwmsr(uint32_t addr, uint64_t *valp, void (*rw)(uint32_t, uint64_t *))
{
        jmp_buf pcb, *oldpcb = NULL;

        if (setjmp(pcb) != 0) {
                kmdb_dpi_restore_fault_hdlr(oldpcb);
                return (-1); /* errno is set for us */
        }

        oldpcb = kmdb_dpi_set_fault_hdlr(&pcb);
        rw(addr, valp);
        kmdb_dpi_restore_fault_hdlr(oldpcb);

        return (0);
}

/*ARGSUSED*/
int
kmt_rdmsr(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
{
        uint64_t val;

        if (!(flags & DCMD_ADDRSPEC))
                return (DCMD_USAGE);

        if (kmt_rwmsr(addr, &val, rdmsr) < 0) {
                warn("rdmsr failed");
                return (DCMD_ERR);
        }

        mdb_printf("%llx\n", (u_longlong_t)val);

        return (DCMD_OK);
}

/*ARGSUSED*/
int
kmt_wrmsr(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
{
        uint64_t val;

        if (!(flags & DCMD_ADDRSPEC) || argc != 1)
                return (DCMD_USAGE);

        val = mdb_argtoull(argv);

        if (kmt_rwmsr(addr, &val, wrmsr)) {
                warn("wrmsr failed");
                return (DCMD_ERR);
        }

        return (DCMD_OK);
}

/*ARGSUSED*/
ssize_t
kmt_write(mdb_tgt_t *t, const void *buf, size_t nbytes, uintptr_t addr)
{
        if (!(t->t_flags & MDB_TGT_F_ALLOWIO) &&
            (nbytes = kmdb_kdi_range_is_nontoxic(addr, nbytes, 1)) == 0)
                return (set_errno(EMDB_NOMAP));

        /*
         * No writes to user space are allowed.  If we were to allow it, we'd
         * be in the unfortunate situation where kmdb could place a breakpoint
         * on a userspace executable page; this dirty page would end up being
         * flushed back to disk, incurring sadness when it's next executed.
         * Besides, we can't allow trapping in from userspace anyway.
         */
        if (addr < kmdb_kdi_get_userlimit())
                return (set_errno(EMDB_TGTNOTSUP));

        return (kmt_rw(t, (void *)buf, nbytes, addr, kmt_writer));
}

/*ARGSUSED*/
static ssize_t
kmt_iorw(mdb_tgt_t *t, void *buf, size_t nbytes, uint64_t addr,
    void (*iorw)(void *, size_t, uintptr_t))
{
        jmp_buf pcb, *oldpcb = NULL;

        if (kmt_io_check(nbytes, addr, IOCHECK_NOWARN) < 0)
                return (-1); /* errno is set for us */

        if (setjmp(pcb) != 0) {
                kmdb_dpi_restore_fault_hdlr(oldpcb);
                return (-1); /* errno is set for us */
        }

        oldpcb = kmdb_dpi_set_fault_hdlr(&pcb);
        iorw(buf, nbytes, addr);
        kmdb_dpi_restore_fault_hdlr(oldpcb);

        return (nbytes);
}

/*ARGSUSED*/
ssize_t
kmt_ioread(mdb_tgt_t *t, void *buf, size_t nbytes, uintptr_t addr)
{
        return (kmt_iorw(t, buf, nbytes, addr, kmt_in));
}

/*ARGSUSED*/
ssize_t
kmt_iowrite(mdb_tgt_t *t, const void *buf, size_t nbytes, uintptr_t addr)
{
        return (kmt_iorw(t, (void *)buf, nbytes, addr, kmt_out));
}

static int
kmt_pcicfg_common(uintptr_t off, uint32_t *valp, const mdb_arg_t *argv,
    void (*rw)(void *, size_t, uintptr_t))
{
        uint32_t bus, dev, func;
        uint32_t addr;

        bus = (uint32_t)mdb_argtoull(&argv[0]);
        dev = (uint32_t)mdb_argtoull(&argv[1]);
        func = (uint32_t)mdb_argtoull(&argv[2]);

        if ((bus & 0xffff) != bus) {
                warn("invalid bus number (must be 0-0xffff)\n");
                return (DCMD_ERR);
        }

        if ((dev & 0x1f) != dev) {
                warn("invalid device number (must be 0-0x1f)\n");
                return (DCMD_ERR);
        }

        if ((func & 0x7) != func) {
                warn("invalid function number (must be 0-7)\n");
                return (DCMD_ERR);
        }

        if ((off & 0xfc) != off) {
                warn("invalid register number (must be 0-0xff, and 4-byte "
                    "aligned\n");
                return (DCMD_ERR);
        }

        addr = PCI_CADDR1(bus, dev, func, off);

        if (kmt_iowrite(mdb.m_target, &addr, sizeof (addr), PCI_CONFADD) !=
            sizeof (addr)) {
                warn("write of PCI_CONFADD failed");
                return (DCMD_ERR);
        }

        if (kmt_iorw(mdb.m_target, valp, sizeof (*valp), PCI_CONFDATA, rw) !=
            sizeof (*valp)) {
                warn("access to PCI_CONFDATA failed");
                return (DCMD_ERR);
        }

        return (DCMD_OK);
}

/*ARGSUSED*/
int
kmt_rdpcicfg(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
{
        uint32_t val;

        if (argc != 3 || !(flags & DCMD_ADDRSPEC))
                return (DCMD_USAGE);

        if (kmt_pcicfg_common(addr, &val, argv, kmt_in) != DCMD_OK)
                return (DCMD_ERR);

        mdb_printf("%llx\n", (u_longlong_t)val);

        return (DCMD_OK);
}

/*ARGSUSED*/
int
kmt_wrpcicfg(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
{
        uint32_t val;

        if (argc != 4 || !(flags & DCMD_ADDRSPEC))
                return (DCMD_USAGE);

        val = (uint32_t)mdb_argtoull(&argv[3]);

        if (kmt_pcicfg_common(addr, &val, argv, kmt_out) != DCMD_OK)
                return (DCMD_ERR);

        return (DCMD_OK);
}

const char *
kmt_trapname(int trapnum)
{
        static char trapname[11];

        switch (trapnum) {
        case T_ZERODIV:
                return ("division by zero (#de) trap");
        case T_SGLSTP:
                return ("single-step (#db) trap");
        case T_NMIFLT:
                return ("NMI");
        case T_BPTFLT:
                return ("breakpoint (#bp) trap");
        case T_ILLINST:
                return ("illegal instruction (#ud) trap");
        case T_SEGFLT:
                return ("segment not present (#np) trap");
        case T_STKFLT:
                return ("stack (#ss) trap");
        case T_GPFLT:
                return ("general protection (#gp) trap");
        case T_PGFLT:
                return ("page fault (#pf) trap");
        case T_ALIGNMENT:
                return ("alignment check (#ac) trap");
        case T_MCE:
                return ("machine check (#mc) trap");
        case T_SIMDFPE:
                return ("SSE/SSE2 (#xm) trap");
        case T_DBGENTR:
                return ("debugger entry trap");
        default:
                (void) mdb_snprintf(trapname, sizeof (trapname), "trap %#x",
                    trapnum);
                return (trapname);
        }
}

void
kmt_init_isadep(mdb_tgt_t *t)
{
        kmt_data_t *kmt = t->t_data;

        kmt->kmt_rds = mdb_isa_kregs;

        kmt->kmt_trapmax = KMT_MAXTRAPNO;
        kmt->kmt_trapmap = mdb_zalloc(BT_SIZEOFMAP(kmt->kmt_trapmax), UM_SLEEP);

        /* Traps for which we want to provide an explicit message */
        (void) mdb_tgt_add_fault(t, T_ZERODIV, MDB_TGT_SPEC_INTERNAL,
            no_se_f, NULL);
        (void) mdb_tgt_add_fault(t, T_ILLINST, MDB_TGT_SPEC_INTERNAL,
            no_se_f, NULL);
        (void) mdb_tgt_add_fault(t, T_SEGFLT, MDB_TGT_SPEC_INTERNAL,
            no_se_f, NULL);
        (void) mdb_tgt_add_fault(t, T_STKFLT, MDB_TGT_SPEC_INTERNAL,
            no_se_f, NULL);
        (void) mdb_tgt_add_fault(t, T_GPFLT, MDB_TGT_SPEC_INTERNAL,
            no_se_f, NULL);
        (void) mdb_tgt_add_fault(t, T_PGFLT, MDB_TGT_SPEC_INTERNAL,
            no_se_f, NULL);
        (void) mdb_tgt_add_fault(t, T_ALIGNMENT, MDB_TGT_SPEC_INTERNAL,
            no_se_f, NULL);
        (void) mdb_tgt_add_fault(t, T_MCE, MDB_TGT_SPEC_INTERNAL,
            no_se_f, NULL);
        (void) mdb_tgt_add_fault(t, T_SIMDFPE, MDB_TGT_SPEC_INTERNAL,
            no_se_f, NULL);

        /*
         * Traps which will be handled elsewhere, and which therefore don't
         * need the trap-based message.
         */
        BT_SET(kmt->kmt_trapmap, T_SGLSTP);
        BT_SET(kmt->kmt_trapmap, T_BPTFLT);
        BT_SET(kmt->kmt_trapmap, T_DBGENTR);

        /* Catch-all for traps not explicitly listed here */
        (void) mdb_tgt_add_fault(t, KMT_TRAP_NOTENUM, MDB_TGT_SPEC_INTERNAL,
            no_se_f, NULL);
}

void
kmt_startup_isadep(mdb_tgt_t *t)
{
        kmt_data_t *kmt = t->t_data;

        /*
         * The stack trace and ::step out code need to detect "interrupt"
         * frames.  The heuristic they use to detect said frames requires the
         * addresses of routines that can generate them.
         */
        (void) mdb_tgt_lookup_by_name(t, MDB_TGT_OBJ_EXEC,
            "cmnint", &kmt->kmt_intrsyms._kmt_cmnint, NULL);
        (void) mdb_tgt_lookup_by_name(t, MDB_TGT_OBJ_EXEC,
            "cmntrap", &kmt->kmt_intrsyms._kmt_cmntrap, NULL);
        (void) mdb_tgt_lookup_by_name(t, MDB_TGT_OBJ_EXEC,
            "sys_sysenter", &kmt->kmt_intrsyms._kmt_sysenter, NULL);
        (void) mdb_tgt_lookup_by_name(t, MDB_TGT_OBJ_EXEC,
            "brand_sys_sysenter", &kmt->kmt_intrsyms._kmt_brand_sysenter, NULL);
#if defined(__amd64)
        (void) mdb_tgt_lookup_by_name(t, MDB_TGT_OBJ_EXEC,
            "sys_syscall", &kmt->kmt_intrsyms._kmt_syscall, NULL);
        (void) mdb_tgt_lookup_by_name(t, MDB_TGT_OBJ_EXEC,
            "brand_sys_syscall", &kmt->kmt_intrsyms._kmt_brand_syscall, NULL);
#endif
}