root/usr/src/uts/i86pc/io/immu.c
/*
 * 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
 */
/*
 * Portions Copyright (c) 2010, Oracle and/or its affiliates.
 * All rights reserved.
 */
/*
 * Copyright (c) 2009, Intel Corporation.
 * All rights reserved.
 */

/*
 * Copyright 2023 Oxide Computer Company
 */

/*
 * Intel IOMMU implementation
 * This file contains Intel IOMMU code exported
 * to the rest of the system and code that deals
 * with the Intel IOMMU as a whole.
 */

#include <sys/conf.h>
#include <sys/modctl.h>
#include <sys/pci.h>
#include <sys/pci_impl.h>
#include <sys/sysmacros.h>
#include <sys/ddi.h>
#include <sys/ddidmareq.h>
#include <sys/ddi_impldefs.h>
#include <sys/ddifm.h>
#include <sys/sunndi.h>
#include <sys/debug.h>
#include <sys/fm/protocol.h>
#include <sys/note.h>
#include <sys/apic.h>
#include <vm/hat_i86.h>
#include <sys/smp_impldefs.h>
#include <sys/spl.h>
#include <sys/archsystm.h>
#include <sys/x86_archext.h>
#include <sys/avl.h>
#include <sys/bootconf.h>
#include <sys/bootinfo.h>
#include <sys/atomic.h>
#include <sys/immu.h>
/* ########################### Globals and tunables ######################## */
/*
 * Global switches (boolean) that can be toggled either via boot options
 * or via /etc/system or kmdb
 */

/* Various features */
boolean_t immu_enable = B_TRUE;
boolean_t immu_dvma_enable = B_TRUE;

/* accessed in other files so not static */
boolean_t immu_gfxdvma_enable = B_TRUE;
boolean_t immu_intrmap_enable = B_FALSE;
boolean_t immu_qinv_enable = B_TRUE;

/* various quirks that need working around */

/* XXX We always map page 0 read/write for now */
boolean_t immu_quirk_usbpage0 = B_TRUE;
boolean_t immu_quirk_usbrmrr = B_TRUE;
boolean_t immu_quirk_usbfullpa;
boolean_t immu_quirk_mobile4;

/* debug messages */
boolean_t immu_dmar_print;

/* Tunables */
int64_t immu_flush_gran = 5;

immu_flags_t immu_global_dvma_flags;

/* ############  END OPTIONS section ################ */

/*
 * Global used internally by Intel IOMMU code
 */
dev_info_t *root_devinfo;
kmutex_t immu_lock;
list_t immu_list;
boolean_t immu_setup;
boolean_t immu_running;
boolean_t immu_quiesced;

/* ######################## END Globals and tunables ###################### */
/* Globals used only in this file */
static char **black_array;
static uint_t nblacks;

static char **unity_driver_array;
static uint_t nunity;
static char **xlate_driver_array;
static uint_t nxlate;

static char **premap_driver_array;
static uint_t npremap;
static char **nopremap_driver_array;
static uint_t nnopremap;
/* ###################### Utility routines ############################# */

/*
 * Check if the device has mobile 4 chipset
 */
static int
check_mobile4(dev_info_t *dip, void *arg)
{
        _NOTE(ARGUNUSED(arg));
        int vendor, device;
        int *ip = (int *)arg;

        vendor = ddi_prop_get_int(DDI_DEV_T_ANY, dip, DDI_PROP_DONTPASS,
            "vendor-id", -1);
        device = ddi_prop_get_int(DDI_DEV_T_ANY, dip, DDI_PROP_DONTPASS,
            "device-id", -1);

        if (vendor == 0x8086 && device == 0x2a40) {
                *ip = B_TRUE;
                ddi_err(DER_NOTE, dip, "iommu: Mobile 4 chipset detected. "
                    "Force setting IOMMU write buffer");
                return (DDI_WALK_TERMINATE);
        } else {
                return (DDI_WALK_CONTINUE);
        }
}

static void
map_bios_rsvd_mem(dev_info_t *dip)
{
        struct memlist *mp;

        /*
         * Make sure the domain for the device is set up before
         * mapping anything.
         */
        (void) immu_dvma_device_setup(dip, 0);

        memlist_read_lock();

        mp = bios_rsvd;
        while (mp != NULL) {
                memrng_t mrng = {0};

                ddi_err(DER_LOG, dip, "iommu: Mapping BIOS rsvd range "
                    "[0x%" PRIx64 " - 0x%"PRIx64 "]\n", mp->ml_address,
                    mp->ml_address + mp->ml_size);

                mrng.mrng_start = IMMU_ROUNDOWN(mp->ml_address);
                mrng.mrng_npages = IMMU_ROUNDUP(mp->ml_size) / IMMU_PAGESIZE;

                (void) immu_map_memrange(dip, &mrng);

                mp = mp->ml_next;
        }

        memlist_read_unlock();
}


/*
 * Check if the driver requests a specific type of mapping.
 */
/*ARGSUSED*/
static void
check_conf(dev_info_t *dip, void *arg)
{
        immu_devi_t *immu_devi;
        const char *dname;
        uint_t i;
        int hasmapprop = 0, haspreprop = 0;
        boolean_t old_premap;

        /*
         * Only PCI devices can use an IOMMU. Legacy ISA devices
         * are handled in check_lpc.
         */
        if (!DEVI_IS_PCI(dip))
                return;

        dname = ddi_driver_name(dip);
        if (dname == NULL)
                return;
        immu_devi = immu_devi_get(dip);

        for (i = 0; i < nunity; i++) {
                if (strcmp(unity_driver_array[i], dname) == 0) {
                        hasmapprop = 1;
                        immu_devi->imd_dvma_flags |= IMMU_FLAGS_UNITY;
                }
        }

        for (i = 0; i < nxlate; i++) {
                if (strcmp(xlate_driver_array[i], dname) == 0) {
                        hasmapprop = 1;
                        immu_devi->imd_dvma_flags &= ~IMMU_FLAGS_UNITY;
                }
        }

        old_premap = immu_devi->imd_use_premap;

        for (i = 0; i < nnopremap; i++) {
                if (strcmp(nopremap_driver_array[i], dname) == 0) {
                        haspreprop = 1;
                        immu_devi->imd_use_premap = B_FALSE;
                }
        }

        for (i = 0; i < npremap; i++) {
                if (strcmp(premap_driver_array[i], dname) == 0) {
                        haspreprop = 1;
                        immu_devi->imd_use_premap = B_TRUE;
                }
        }

        /*
         * Report if we changed the value from the default.
         */
        if (hasmapprop && (immu_devi->imd_dvma_flags ^ immu_global_dvma_flags))
                ddi_err(DER_LOG, dip, "using %s DVMA mapping",
                    immu_devi->imd_dvma_flags & IMMU_FLAGS_UNITY ?
                    DDI_DVMA_MAPTYPE_UNITY : DDI_DVMA_MAPTYPE_XLATE);

        if (haspreprop && (immu_devi->imd_use_premap != old_premap))
                ddi_err(DER_LOG, dip, "%susing premapped DVMA space",
                    immu_devi->imd_use_premap ? "" : "not ");
}

/*
 * Check if the device is USB controller
 */
/*ARGSUSED*/
static void
check_usb(dev_info_t *dip, void *arg)
{
        const char *drv = ddi_driver_name(dip);
        immu_devi_t *immu_devi;


        /*
         * It's not clear if xHCI really needs these quirks; however, to be on
         * the safe side until we know for certain we add it to the list below.
         */
        if (drv == NULL ||
            (strcmp(drv, "uhci") != 0 && strcmp(drv, "ohci") != 0 &&
            strcmp(drv, "ehci") != 0 && strcmp(drv, "xhci") != 0)) {
                return;
        }

        immu_devi = immu_devi_get(dip);

        /*
         * If unit mappings are already specified, globally or
         * locally, we're done here, since that covers both
         * quirks below.
         */
        if (immu_devi->imd_dvma_flags & IMMU_FLAGS_UNITY)
                return;

        /* This must come first since it does unity mapping */
        if (immu_quirk_usbfullpa == B_TRUE) {
                immu_devi->imd_dvma_flags |= IMMU_FLAGS_UNITY;
        } else if (immu_quirk_usbrmrr == B_TRUE) {
                ddi_err(DER_LOG, dip, "Applying USB RMRR quirk");
                map_bios_rsvd_mem(dip);
        }
}

/*
 * Check if the device is a LPC device
 */
/*ARGSUSED*/
static void
check_lpc(dev_info_t *dip, void *arg)
{
        immu_devi_t *immu_devi;

        immu_devi = immu_devi_get(dip);
        if (immu_devi->imd_lpc == B_TRUE) {
                ddi_err(DER_LOG, dip, "iommu: Found LPC device");
                /* This will put the immu_devi on the LPC "specials" list */
                (void) immu_dvma_device_setup(dip, IMMU_FLAGS_SLEEP);
        }
}

/*
 * Check if the device is a GFX device
 */
/*ARGSUSED*/
static void
check_gfx(dev_info_t *dip, void *arg)
{
        immu_devi_t *immu_devi;

        immu_devi = immu_devi_get(dip);
        if (immu_devi->imd_display == B_TRUE) {
                immu_devi->imd_dvma_flags |= IMMU_FLAGS_UNITY;
                ddi_err(DER_LOG, dip, "iommu: Found GFX device");
                /* This will put the immu_devi on the GFX "specials" list */
                (void) immu_dvma_get_immu(dip, IMMU_FLAGS_SLEEP);
        }
}

static void
walk_tree(int (*f)(dev_info_t *, void *), void *arg)
{
        ndi_devi_enter(root_devinfo);
        ddi_walk_devs(ddi_get_child(root_devinfo), f, arg);
        ndi_devi_exit(root_devinfo);
}

static int
check_pre_setup_quirks(dev_info_t *dip, void *arg)
{
        /* just 1 check right now */
        return (check_mobile4(dip, arg));
}

static int
check_pre_startup_quirks(dev_info_t *dip, void *arg)
{
        if (immu_devi_set(dip, IMMU_FLAGS_SLEEP) != DDI_SUCCESS) {
                ddi_err(DER_PANIC, dip, "Failed to get immu_devi");
        }

        check_gfx(dip, arg);

        check_lpc(dip, arg);

        check_conf(dip, arg);

        check_usb(dip, arg);

        return (DDI_WALK_CONTINUE);
}

static void
pre_setup_quirks(void)
{
        walk_tree(check_pre_setup_quirks, &immu_quirk_mobile4);
}

static void
pre_startup_quirks(void)
{
        walk_tree(check_pre_startup_quirks, NULL);

        immu_dmar_rmrr_map();
}

static int
get_conf_str(char *bopt, char **val)
{
        int ret;

        /*
         * Check the rootnex.conf property
         * Fake up a dev_t since searching the global
         * property list needs it
         */
        ret = ddi_prop_lookup_string(
            makedevice(ddi_name_to_major("rootnex"), 0),
            root_devinfo, DDI_PROP_DONTPASS | DDI_PROP_ROOTNEX_GLOBAL,
            bopt, val);

        return (ret);
}

/*
 * get_conf_opt()
 *      get a rootnex.conf setting  (always a boolean)
 */
static void
get_conf_opt(char *bopt, boolean_t *kvar)
{
        char *val = NULL;

        /*
         * Check the rootnex.conf property
         * Fake up a dev_t since searching the global
         * property list needs it
         */

        if (get_conf_str(bopt, &val) != DDI_PROP_SUCCESS)
                return;

        if (strcmp(val, "true") == 0) {
                *kvar = B_TRUE;
        } else if (strcmp(val, "false") == 0) {
                *kvar = B_FALSE;
        } else {
                ddi_err(DER_WARN, NULL, "rootnex.conf switch %s=\"%s\" ",
                    "is not set to true or false. Ignoring option.",
                    bopt, val);
        }
        ddi_prop_free(val);
}

/*
 * get_bootopt()
 *      check a boot option  (always a boolean)
 */
static int
get_boot_str(char *bopt, char **val)
{
        int ret;

        ret = ddi_prop_lookup_string(DDI_DEV_T_ANY, root_devinfo,
            DDI_PROP_DONTPASS, bopt, val);

        return (ret);
}

static void
get_bootopt(char *bopt, boolean_t *kvar)
{
        char *val = NULL;

        /*
         * All boot options set at the GRUB menu become
         * properties on the rootnex.
         */
        if (get_boot_str(bopt, &val) != DDI_PROP_SUCCESS)
                return;

        if (strcmp(val, "true") == 0) {
                *kvar = B_TRUE;
        } else if (strcmp(val, "false") == 0) {
                *kvar = B_FALSE;
        } else {
                ddi_err(DER_WARN, NULL, "boot option %s=\"%s\" ",
                    "is not set to true or false. Ignoring option.",
                    bopt, val);
        }
        ddi_prop_free(val);
}

static void
get_boot_dvma_mode(void)
{
        char *val = NULL;

        if (get_boot_str(DDI_DVMA_MAPTYPE_ROOTNEX_PROP, &val)
            != DDI_PROP_SUCCESS)
                return;

        if (strcmp(val, DDI_DVMA_MAPTYPE_UNITY) == 0) {
                immu_global_dvma_flags |= IMMU_FLAGS_UNITY;
        } else if (strcmp(val, DDI_DVMA_MAPTYPE_XLATE) == 0) {
                immu_global_dvma_flags &= ~IMMU_FLAGS_UNITY;
        } else {
                ddi_err(DER_WARN, NULL, "bad value \"%s\" for boot option %s",
                    val, DDI_DVMA_MAPTYPE_ROOTNEX_PROP);
        }
        ddi_prop_free(val);
}

static void
get_conf_dvma_mode(void)
{
        char *val = NULL;

        if (get_conf_str(DDI_DVMA_MAPTYPE_ROOTNEX_PROP, &val)
            != DDI_PROP_SUCCESS)
                return;

        if (strcmp(val, DDI_DVMA_MAPTYPE_UNITY) == 0) {
                immu_global_dvma_flags |= IMMU_FLAGS_UNITY;
        } else if (strcmp(val, DDI_DVMA_MAPTYPE_XLATE) == 0) {
                immu_global_dvma_flags &= ~IMMU_FLAGS_UNITY;
        } else {
                ddi_err(DER_WARN, NULL, "bad value \"%s\" for rootnex "
                    "option %s", val, DDI_DVMA_MAPTYPE_ROOTNEX_PROP);
        }
        ddi_prop_free(val);
}


static void
get_conf_tunables(char *bopt, int64_t *ivar)
{
        int64_t *iarray;
        uint_t n;

        /*
         * Check the rootnex.conf property
         * Fake up a dev_t since searching the global
         * property list needs it
         */
        if (ddi_prop_lookup_int64_array(
            makedevice(ddi_name_to_major("rootnex"), 0), root_devinfo,
            DDI_PROP_DONTPASS | DDI_PROP_ROOTNEX_GLOBAL, bopt,
            &iarray, &n) != DDI_PROP_SUCCESS) {
                return;
        }

        if (n != 1) {
                ddi_err(DER_WARN, NULL, "More than one value specified for "
                    "%s property. Ignoring and using default",
                    "immu-flush-gran");
                ddi_prop_free(iarray);
                return;
        }

        if (iarray[0] < 0) {
                ddi_err(DER_WARN, NULL, "Negative value specified for "
                    "%s property. Inoring and Using default value",
                    "immu-flush-gran");
                ddi_prop_free(iarray);
                return;
        }

        *ivar = iarray[0];

        ddi_prop_free(iarray);
}

static void
read_conf_options(void)
{
        /* enable/disable options */
        get_conf_opt("immu-enable", &immu_enable);
        get_conf_opt("immu-dvma-enable", &immu_dvma_enable);
        get_conf_opt("immu-gfxdvma-enable", &immu_gfxdvma_enable);
        get_conf_opt("immu-intrmap-enable", &immu_intrmap_enable);
        get_conf_opt("immu-qinv-enable", &immu_qinv_enable);

        /* workaround switches */
        get_conf_opt("immu-quirk-usbpage0", &immu_quirk_usbpage0);
        get_conf_opt("immu-quirk-usbfullpa", &immu_quirk_usbfullpa);
        get_conf_opt("immu-quirk-usbrmrr", &immu_quirk_usbrmrr);

        /* debug printing */
        get_conf_opt("immu-dmar-print", &immu_dmar_print);

        /* get tunables */
        get_conf_tunables("immu-flush-gran", &immu_flush_gran);

        get_conf_dvma_mode();
}

static void
read_boot_options(void)
{
        /* enable/disable options */
        get_bootopt("immu-enable", &immu_enable);
        get_bootopt("immu-dvma-enable", &immu_dvma_enable);
        get_bootopt("immu-gfxdvma-enable", &immu_gfxdvma_enable);
        get_bootopt("immu-intrmap-enable", &immu_intrmap_enable);
        get_bootopt("immu-qinv-enable", &immu_qinv_enable);

        /* workaround switches */
        get_bootopt("immu-quirk-usbpage0", &immu_quirk_usbpage0);
        get_bootopt("immu-quirk-usbfullpa", &immu_quirk_usbfullpa);
        get_bootopt("immu-quirk-usbrmrr", &immu_quirk_usbrmrr);

        /* debug printing */
        get_bootopt("immu-dmar-print", &immu_dmar_print);

        get_boot_dvma_mode();
}

static void
mapping_list_setup(void)
{
        char **string_array;
        uint_t nstrings;

        if (ddi_prop_lookup_string_array(
            makedevice(ddi_name_to_major("rootnex"), 0), root_devinfo,
            DDI_PROP_DONTPASS | DDI_PROP_ROOTNEX_GLOBAL,
            "immu-dvma-unity-drivers",
            &string_array, &nstrings) == DDI_PROP_SUCCESS) {
                unity_driver_array = string_array;
                nunity = nstrings;
        }

        if (ddi_prop_lookup_string_array(
            makedevice(ddi_name_to_major("rootnex"), 0), root_devinfo,
            DDI_PROP_DONTPASS | DDI_PROP_ROOTNEX_GLOBAL,
            "immu-dvma-xlate-drivers",
            &string_array, &nstrings) == DDI_PROP_SUCCESS) {
                xlate_driver_array = string_array;
                nxlate = nstrings;
        }

        if (ddi_prop_lookup_string_array(
            makedevice(ddi_name_to_major("rootnex"), 0), root_devinfo,
            DDI_PROP_DONTPASS | DDI_PROP_ROOTNEX_GLOBAL,
            "immu-dvma-premap-drivers",
            &string_array, &nstrings) == DDI_PROP_SUCCESS) {
                premap_driver_array = string_array;
                npremap = nstrings;
        }

        if (ddi_prop_lookup_string_array(
            makedevice(ddi_name_to_major("rootnex"), 0), root_devinfo,
            DDI_PROP_DONTPASS | DDI_PROP_ROOTNEX_GLOBAL,
            "immu-dvma-nopremap-drivers",
            &string_array, &nstrings) == DDI_PROP_SUCCESS) {
                nopremap_driver_array = string_array;
                nnopremap = nstrings;
        }
}

/*
 * Note, this will not catch hardware not enumerated
 * in early boot
 */
static boolean_t
blacklisted_driver(void)
{
        char **strptr;
        int i;
        major_t maj;

        /* need at least 2 strings */
        if (nblacks < 2) {
                return (B_FALSE);
        }

        for (i = 0; nblacks - i > 1; i++) {
                strptr = &black_array[i];
                if (strcmp(*strptr++, "DRIVER") == 0) {
                        if ((maj = ddi_name_to_major(*strptr++))
                            != DDI_MAJOR_T_NONE) {
                                /* is there hardware bound to this drvr */
                                if (devnamesp[maj].dn_head != NULL) {
                                        return (B_TRUE);
                                }
                        }
                        i += 1;   /* for loop adds 1, so add only 1 here */
                }
        }

        return (B_FALSE);
}

static boolean_t
blacklisted_smbios(void)
{
        id_t smid;
        smbios_hdl_t *smhdl;
        smbios_info_t sminf;
        smbios_system_t smsys;
        char *mfg, *product, *version;
        char **strptr;
        int i;

        /* need at least 4 strings for this setting */
        if (nblacks < 4) {
                return (B_FALSE);
        }

        smhdl = smbios_open(NULL, SMB_VERSION, ksmbios_flags, NULL);
        if (smhdl == NULL ||
            (smid = smbios_info_system(smhdl, &smsys)) == SMB_ERR ||
            smbios_info_common(smhdl, smid, &sminf) == SMB_ERR) {
                return (B_FALSE);
        }

        mfg = (char *)sminf.smbi_manufacturer;
        product = (char *)sminf.smbi_product;
        version = (char *)sminf.smbi_version;

        ddi_err(DER_CONT, NULL, "?System SMBIOS information:\n");
        ddi_err(DER_CONT, NULL, "?Manufacturer = <%s>\n", mfg);
        ddi_err(DER_CONT, NULL, "?Product = <%s>\n", product);
        ddi_err(DER_CONT, NULL, "?Version = <%s>\n", version);

        for (i = 0; nblacks - i > 3; i++) {
                strptr = &black_array[i];
                if (strcmp(*strptr++, "SMBIOS") == 0) {
                        if (strcmp(*strptr++, mfg) == 0 &&
                            (*strptr[0] == '\0' ||
                            strcmp(*strptr++, product) == 0) &&
                            (*strptr[0] == '\0' ||
                            strcmp(*strptr++, version) == 0)) {
                                return (B_TRUE);
                        }
                        i += 3;
                }
        }

        return (B_FALSE);
}

static boolean_t
blacklisted_acpi(void)
{
        if (nblacks == 0) {
                return (B_FALSE);
        }

        return (immu_dmar_blacklisted(black_array, nblacks));
}

/*
 * Check if system is blacklisted by Intel IOMMU driver
 * i.e. should Intel IOMMU be disabled on this system
 * Currently a system can be blacklistd based on the
 * following bases:
 *
 * 1. DMAR ACPI table information.
 *    This information includes things like
 *    manufacturer and revision number. If rootnex.conf
 *    has matching info set in its blacklist property
 *    then Intel IOMMu will be disabled
 *
 * 2. SMBIOS information
 *
 * 3. Driver installed - useful if a particular
 *    driver or hardware is toxic if Intel IOMMU
 *    is turned on.
 */

static void
blacklist_setup(void)
{
        char **string_array;
        uint_t nstrings;

        /*
         * Check the rootnex.conf blacklist property.
         * Fake up a dev_t since searching the global
         * property list needs it
         */
        if (ddi_prop_lookup_string_array(
            makedevice(ddi_name_to_major("rootnex"), 0), root_devinfo,
            DDI_PROP_DONTPASS | DDI_PROP_ROOTNEX_GLOBAL, "immu-blacklist",
            &string_array, &nstrings) != DDI_PROP_SUCCESS) {
                return;
        }

        /* smallest blacklist criteria works with multiples of 2 */
        if (nstrings % 2 != 0) {
                ddi_err(DER_WARN, NULL, "Invalid IOMMU blacklist "
                    "rootnex.conf: number of strings must be a "
                    "multiple of 2");
                ddi_prop_free(string_array);
                return;
        }

        black_array = string_array;
        nblacks = nstrings;
}

static void
blacklist_destroy(void)
{
        if (black_array) {
                ddi_prop_free(black_array);
                black_array = NULL;
                nblacks = 0;
        }
}

static char *
immu_alloc_name(const char *str, int instance)
{
        size_t slen;
        char *s;

        slen = strlen(str) + IMMU_ISTRLEN + 1;
        s = kmem_zalloc(slen, VM_SLEEP);
        if (s != NULL)
                (void) snprintf(s, slen, "%s%d", str, instance);

        return (s);
}


/*
 * Now set all the fields in the order they are defined
 * We do this only as a defensive-coding practice, it is
 * not a correctness issue.
 */
static void *
immu_state_alloc(int seg, void *dmar_unit)
{
        immu_t *immu;
        char *nodename, *hcachename, *pcachename;
        int instance;

        dmar_unit = immu_dmar_walk_units(seg, dmar_unit);
        if (dmar_unit == NULL) {
                /* No more IOMMUs in this segment */
                return (NULL);
        }

        immu = kmem_zalloc(sizeof (immu_t), KM_SLEEP);

        mutex_init(&(immu->immu_lock), NULL, MUTEX_DRIVER, NULL);

        mutex_enter(&(immu->immu_lock));

        immu->immu_dmar_unit = dmar_unit;
        immu->immu_dip = immu_dmar_unit_dip(dmar_unit);

        nodename = ddi_node_name(immu->immu_dip);
        instance = ddi_get_instance(immu->immu_dip);

        immu->immu_name = immu_alloc_name(nodename, instance);
        if (immu->immu_name == NULL)
                return (NULL);

        /*
         * the immu_intr_lock mutex is grabbed by the IOMMU
         * unit's interrupt handler so we need to use an
         * interrupt cookie for the mutex
         */
        mutex_init(&(immu->immu_intr_lock), NULL, MUTEX_DRIVER,
            (void *)ipltospl(IMMU_INTR_IPL));

        /* IOMMU regs related */
        mutex_init(&(immu->immu_regs_lock), NULL, MUTEX_DEFAULT, NULL);
        cv_init(&(immu->immu_regs_cv), NULL, CV_DEFAULT, NULL);
        immu->immu_regs_busy = B_FALSE;

        /* DVMA related */
        immu->immu_dvma_coherent = B_FALSE;

        /* DVMA context related */
        rw_init(&(immu->immu_ctx_rwlock), NULL, RW_DEFAULT, NULL);

        /* DVMA domain related */
        list_create(&(immu->immu_domain_list), sizeof (domain_t),
            offsetof(domain_t, dom_immu_node));

        /* DVMA special device lists */
        immu->immu_dvma_gfx_only = B_FALSE;
        list_create(&(immu->immu_dvma_lpc_list), sizeof (immu_devi_t),
            offsetof(immu_devi_t, imd_spc_node));
        list_create(&(immu->immu_dvma_gfx_list), sizeof (immu_devi_t),
            offsetof(immu_devi_t, imd_spc_node));

        /* interrupt remapping related */
        mutex_init(&(immu->immu_intrmap_lock), NULL, MUTEX_DEFAULT, NULL);

        /* qinv related */
        mutex_init(&(immu->immu_qinv_lock), NULL, MUTEX_DEFAULT, NULL);

        /*
         * insert this immu unit into the system-wide list
         */
        list_insert_tail(&immu_list, immu);

        pcachename = immu_alloc_name("immu_pgtable_cache", instance);
        if (pcachename == NULL)
                return (NULL);

        hcachename = immu_alloc_name("immu_hdl_cache", instance);
        if (hcachename == NULL)
                return (NULL);

        immu->immu_pgtable_cache = kmem_cache_create(pcachename,
            sizeof (pgtable_t), 0, pgtable_ctor, pgtable_dtor, NULL, immu,
            NULL, 0);
        immu->immu_hdl_cache = kmem_cache_create(hcachename,
            sizeof (immu_hdl_priv_t), 64, immu_hdl_priv_ctor,
            NULL, NULL, immu, NULL, 0);

        mutex_exit(&(immu->immu_lock));

        ddi_err(DER_LOG, immu->immu_dip, "unit setup");

        immu_dmar_set_immu(dmar_unit, immu);

        return (dmar_unit);
}

static void
immu_subsystems_setup(void)
{
        int seg;
        void *unit_hdl;

        ddi_err(DER_VERB, NULL,
            "Creating state structures for Intel IOMMU units");

        mutex_init(&immu_lock, NULL, MUTEX_DEFAULT, NULL);
        list_create(&immu_list, sizeof (immu_t), offsetof(immu_t, immu_node));

        mutex_enter(&immu_lock);

        unit_hdl = NULL;
        for (seg = 0; seg < IMMU_MAXSEG; seg++) {
                while (unit_hdl = immu_state_alloc(seg, unit_hdl)) {
                        ;
                }
        }

        immu_regs_setup(&immu_list);    /* subsequent code needs this first */
        immu_dvma_setup(&immu_list);
        if (immu_qinv_setup(&immu_list) == DDI_SUCCESS)
                immu_intrmap_setup(&immu_list);
        else
                immu_intrmap_enable = B_FALSE;

        mutex_exit(&immu_lock);
}

/*
 * immu_subsystems_startup()
 *      startup all units that were setup
 */
static void
immu_subsystems_startup(void)
{
        immu_t *immu;
        iommulib_ops_t *iommulib_ops;

        mutex_enter(&immu_lock);

        immu_dmar_startup();

        immu = list_head(&immu_list);
        for (; immu; immu = list_next(&immu_list, immu)) {

                mutex_enter(&(immu->immu_lock));

                immu_intr_register(immu);
                immu_dvma_startup(immu);
                immu_intrmap_startup(immu);
                immu_qinv_startup(immu);

                /*
                 * Set IOMMU unit's regs to do
                 * the actual startup. This will
                 * set immu->immu_running  field
                 * if the unit is successfully
                 * started
                 */
                immu_regs_startup(immu);

                mutex_exit(&(immu->immu_lock));

                iommulib_ops = kmem_alloc(sizeof (iommulib_ops_t), KM_SLEEP);
                *iommulib_ops = immulib_ops;
                iommulib_ops->ilops_data = (void *)immu;
                (void) iommulib_iommu_register(immu->immu_dip, iommulib_ops,
                    &immu->immu_iommulib_handle);
        }

        mutex_exit(&immu_lock);
}

/* ##################  Intel IOMMU internal interfaces ###################### */

/*
 * Internal interfaces for IOMMU code (i.e. not exported to rootnex
 * or rest of system)
 */

/*
 * ddip can be NULL, in which case we walk up until we find the root dip
 * NOTE: We never visit the root dip since its not a hardware node
 */
int
immu_walk_ancestor(
        dev_info_t *rdip,
        dev_info_t *ddip,
        int (*func)(dev_info_t *, void *arg),
        void *arg,
        int *lvlp,
        immu_flags_t immu_flags)
{
        dev_info_t *pdip;
        int level;
        int error = DDI_SUCCESS;

        /* ddip and immu can be NULL */

        /* Hold rdip so that branch is not detached */
        ndi_hold_devi(rdip);
        for (pdip = rdip, level = 1; pdip && pdip != root_devinfo;
            pdip = ddi_get_parent(pdip), level++) {

                if (immu_devi_set(pdip, immu_flags) != DDI_SUCCESS) {
                        error = DDI_FAILURE;
                        break;
                }
                if (func(pdip, arg) == DDI_WALK_TERMINATE) {
                        break;
                }
                if (immu_flags & IMMU_FLAGS_DONTPASS) {
                        break;
                }
                if (pdip == ddip) {
                        break;
                }
        }

        ndi_rele_devi(rdip);

        if (lvlp)
                *lvlp = level;

        return (error);
}

/* ########################  Intel IOMMU entry points ####################### */
/*
 * immu_init()
 *      called from rootnex_attach(). setup but don't startup the Intel IOMMU
 *      This is the first function called in Intel IOMMU code
 */
void
immu_init(void)
{
        char *phony_reg = "A thing of beauty is a joy forever";

        /* Set some global shorthands that are needed by all of IOMMU code */
        root_devinfo = ddi_root_node();

        /*
         * Intel IOMMU only supported only if MMU(CPU) page size is ==
         * IOMMU pages size.
         */
        /*LINTED*/
        if (MMU_PAGESIZE != IMMU_PAGESIZE) {
                ddi_err(DER_WARN, NULL,
                    "MMU page size (%d) is not equal to\n"
                    "IOMMU page size (%d). "
                    "Disabling Intel IOMMU. ",
                    MMU_PAGESIZE, IMMU_PAGESIZE);
                immu_enable = B_FALSE;
                return;
        }

        /*
         * Read rootnex.conf options. Do this before
         * boot options so boot options can override .conf options.
         */
        read_conf_options();

        /*
         * retrieve the Intel IOMMU boot options.
         * Do this before parsing immu ACPI table
         * as a boot option could potentially affect
         * ACPI parsing.
         */
        ddi_err(DER_CONT, NULL, "?Reading Intel IOMMU boot options\n");
        read_boot_options();

        /*
         * Check the IOMMU enable boot-option first.
         * This is so that we can skip parsing the ACPI table
         * if necessary because that may cause problems in
         * systems with buggy BIOS or ACPI tables
         */
        if (immu_enable == B_FALSE) {
                return;
        }

        if (immu_intrmap_enable == B_TRUE)
                immu_qinv_enable = B_TRUE;

        /*
         * Next, check if the system even has an Intel IOMMU
         * We use the presence or absence of the IOMMU ACPI
         * table to detect Intel IOMMU.
         */
        if (immu_dmar_setup() != DDI_SUCCESS) {
                immu_enable = B_FALSE;
                return;
        }

        mapping_list_setup();

        /*
         * Check blacklists
         */
        blacklist_setup();

        if (blacklisted_smbios() == B_TRUE) {
                blacklist_destroy();
                immu_enable = B_FALSE;
                return;
        }

        if (blacklisted_driver() == B_TRUE) {
                blacklist_destroy();
                immu_enable = B_FALSE;
                return;
        }

        /*
         * Read the "raw" DMAR ACPI table to get information
         * and convert into a form we can use.
         */
        if (immu_dmar_parse() != DDI_SUCCESS) {
                blacklist_destroy();
                immu_enable = B_FALSE;
                return;
        }

        /*
         * now that we have processed the ACPI table
         * check if we need to blacklist this system
         * based on ACPI info
         */
        if (blacklisted_acpi() == B_TRUE) {
                immu_dmar_destroy();
                blacklist_destroy();
                immu_enable = B_FALSE;
                return;
        }

        blacklist_destroy();

        /*
         * Check if system has HW quirks.
         */
        pre_setup_quirks();

        /* Now do the rest of the setup */
        immu_subsystems_setup();

        /*
         * Now that the IMMU is setup, create a phony
         * reg prop so that suspend/resume works
         */
        if (ddi_prop_update_byte_array(DDI_DEV_T_NONE, root_devinfo, "reg",
            (uchar_t *)phony_reg, strlen(phony_reg) + 1) != DDI_PROP_SUCCESS) {
                ddi_err(DER_PANIC, NULL, "Failed to create reg prop for "
                    "rootnex node");
                /*NOTREACHED*/
        }

        immu_setup = B_TRUE;
}

/*
 * immu_startup()
 *      called directly by boot code to startup
 *      all units of the IOMMU
 */
void
immu_startup(void)
{
        /*
         * If IOMMU is disabled, do nothing
         */
        if (immu_enable == B_FALSE) {
                return;
        }

        if (immu_setup == B_FALSE) {
                ddi_err(DER_WARN, NULL, "Intel IOMMU not setup, "
                    "skipping IOMMU startup");
                return;
        }

        pre_startup_quirks();

        ddi_err(DER_CONT, NULL,
            "?Starting Intel IOMMU (dmar) units...\n");

        immu_subsystems_startup();

        immu_running = B_TRUE;
}

/*
 * Hook to notify IOMMU code of device tree changes
 */
void
immu_device_tree_changed(void)
{
        if (immu_setup == B_FALSE) {
                return;
        }

        ddi_err(DER_WARN, NULL, "Intel IOMMU currently "
            "does not use device tree updates");
}

/*
 * Hook to notify IOMMU code of memory changes
 */
void
immu_physmem_update(uint64_t addr, uint64_t size)
{
        if (immu_setup == B_FALSE) {
                return;
        }
        immu_dvma_physmem_update(addr, size);
}

/*
 * immu_quiesce()
 *      quiesce all units that are running
 */
int
immu_quiesce(void)
{
        immu_t *immu;
        int ret = DDI_SUCCESS;

        mutex_enter(&immu_lock);

        if (immu_running == B_FALSE) {
                mutex_exit(&immu_lock);
                return (DDI_SUCCESS);
        }

        immu = list_head(&immu_list);
        for (; immu; immu = list_next(&immu_list, immu)) {

                /* if immu is not running, we dont quiesce */
                if (immu->immu_regs_running == B_FALSE)
                        continue;

                /* flush caches */
                rw_enter(&(immu->immu_ctx_rwlock), RW_WRITER);
                immu_flush_context_gbl(immu, &immu->immu_ctx_inv_wait);
                immu_flush_iotlb_gbl(immu, &immu->immu_ctx_inv_wait);
                rw_exit(&(immu->immu_ctx_rwlock));
                immu_regs_wbf_flush(immu);

                mutex_enter(&(immu->immu_lock));

                /*
                 * Set IOMMU unit's regs to do
                 * the actual shutdown.
                 */
                immu_regs_shutdown(immu);
                immu_regs_suspend(immu);

                /* if immu is still running, we failed */
                if (immu->immu_regs_running == B_TRUE)
                        ret = DDI_FAILURE;
                else
                        immu->immu_regs_quiesced = B_TRUE;

                mutex_exit(&(immu->immu_lock));
        }

        if (ret == DDI_SUCCESS) {
                immu_running = B_FALSE;
                immu_quiesced = B_TRUE;
        }
        mutex_exit(&immu_lock);

        return (ret);
}

/*
 * immu_unquiesce()
 *      unquiesce all units
 */
int
immu_unquiesce(void)
{
        immu_t *immu;
        int ret = DDI_SUCCESS;

        mutex_enter(&immu_lock);

        if (immu_quiesced == B_FALSE) {
                mutex_exit(&immu_lock);
                return (DDI_SUCCESS);
        }

        immu = list_head(&immu_list);
        for (; immu; immu = list_next(&immu_list, immu)) {

                mutex_enter(&(immu->immu_lock));

                /* if immu was not quiesced, i.e was not running before */
                if (immu->immu_regs_quiesced == B_FALSE) {
                        mutex_exit(&(immu->immu_lock));
                        continue;
                }

                if (immu_regs_resume(immu) != DDI_SUCCESS) {
                        ret = DDI_FAILURE;
                        mutex_exit(&(immu->immu_lock));
                        continue;
                }

                /* flush caches before unquiesce */
                rw_enter(&(immu->immu_ctx_rwlock), RW_WRITER);
                immu_flush_context_gbl(immu, &immu->immu_ctx_inv_wait);
                immu_flush_iotlb_gbl(immu, &immu->immu_ctx_inv_wait);
                rw_exit(&(immu->immu_ctx_rwlock));

                /*
                 * Set IOMMU unit's regs to do
                 * the actual startup. This will
                 * set immu->immu_regs_running  field
                 * if the unit is successfully
                 * started
                 */
                immu_regs_startup(immu);

                if (immu->immu_regs_running == B_FALSE) {
                        ret = DDI_FAILURE;
                } else {
                        immu_quiesced = B_TRUE;
                        immu_running = B_TRUE;
                        immu->immu_regs_quiesced = B_FALSE;
                }

                mutex_exit(&(immu->immu_lock));
        }

        mutex_exit(&immu_lock);

        return (ret);
}

void
immu_init_inv_wait(immu_inv_wait_t *iwp, const char *name, boolean_t sync)
{
        caddr_t vaddr;
        uint64_t paddr;

        iwp->iwp_sync = sync;

        vaddr = (caddr_t)&iwp->iwp_vstatus;
        paddr = pfn_to_pa(hat_getpfnum(kas.a_hat, vaddr));
        paddr += ((uintptr_t)vaddr) & MMU_PAGEOFFSET;

        iwp->iwp_pstatus = paddr;
        iwp->iwp_name = name;
}

/* ##############  END Intel IOMMU entry points ################## */