qemu/hw/intc/arm_gicv3_its.c

/*
 * ITS emulation for a GICv3-based system
 *
 * Copyright Linaro.org 2021
 *
 * Authors:
 *  Shashi Mallela <shashi.mallela@linaro.org>
 *
 * This work is licensed under the terms of the GNU GPL, version 2 or (at your
 * option) any later version.  See the COPYING file in the top-level directory.
 *
 */

#include "qemu/osdep.h"
#include "qemu/log.h"
#include "trace.h"
#include "hw/qdev-properties.h"
#include "hw/intc/arm_gicv3_its_common.h"
#include "gicv3_internal.h"
#include "qom/object.h"
#include "qapi/error.h"

typedef struct GICv3ITSClass GICv3ITSClass;
/* This is reusing the GICv3ITSState typedef from ARM_GICV3_ITS_COMMON */
DECLARE_OBJ_CHECKERS(GICv3ITSState, GICv3ITSClass,
                     ARM_GICV3_ITS, TYPE_ARM_GICV3_ITS)

struct GICv3ITSClass {
    GICv3ITSCommonClass parent_class;
    void (*parent_reset)(DeviceState *dev);
};

/*
 * This is an internal enum used to distinguish between LPI triggered
 * via command queue and LPI triggered via gits_translater write.
 */
typedef enum ItsCmdType {
    NONE = 0, /* internal indication for GITS_TRANSLATER write */
    CLEAR = 1,
    DISCARD = 2,
    INTERRUPT = 3,
} ItsCmdType;

typedef struct DTEntry {
    bool valid;
    unsigned size;
    uint64_t ittaddr;
} DTEntry;

typedef struct CTEntry {
    bool valid;
    uint32_t rdbase;
} CTEntry;

typedef struct ITEntry {
    bool valid;
    int inttype;
    uint32_t intid;
    uint32_t doorbell;
    uint32_t icid;
    uint32_t vpeid;
} ITEntry;

typedef struct VTEntry {
    bool valid;
    unsigned vptsize;
    uint32_t rdbase;
    uint64_t vptaddr;
} VTEntry;

/*
 * The ITS spec permits a range of CONSTRAINED UNPREDICTABLE options
 * if a command parameter is not correct. These include both "stall
 * processing of the command queue" and "ignore this command, and
 * keep processing the queue". In our implementation we choose that
 * memory transaction errors reading the command packet provoke a
 * stall, but errors in parameters cause us to ignore the command
 * and continue processing.
 * The process_* functions which handle individual ITS commands all
 * return an ItsCmdResult which tells process_cmdq() whether it should
 * stall, keep going because of an error, or keep going because the
 * command was a success.
 */
typedef enum ItsCmdResult {
    CMD_STALL = 0,
    CMD_CONTINUE = 1,
    CMD_CONTINUE_OK = 2,
} ItsCmdResult;

/* True if the ITS supports the GICv4 virtual LPI feature */
static bool its_feature_virtual(GICv3ITSState *s)
{
    return s->typer & R_GITS_TYPER_VIRTUAL_MASK;
}

static inline bool intid_in_lpi_range(uint32_t id)
{
    return id >= GICV3_LPI_INTID_START &&
        id < (1 << (GICD_TYPER_IDBITS + 1));
}

static inline bool valid_doorbell(uint32_t id)
{
    /* Doorbell fields may be an LPI, or 1023 to mean "no doorbell" */
    return id == INTID_SPURIOUS || intid_in_lpi_range(id);
}

static uint64_t baser_base_addr(uint64_t value, uint32_t page_sz)
{
    uint64_t result = 0;

    switch (page_sz) {
    case GITS_PAGE_SIZE_4K:
    case GITS_PAGE_SIZE_16K:
        result = FIELD_EX64(value, GITS_BASER, PHYADDR) << 12;
        break;

    case GITS_PAGE_SIZE_64K:
        result = FIELD_EX64(value, GITS_BASER, PHYADDRL_64K) << 16;
        result |= FIELD_EX64(value, GITS_BASER, PHYADDRH_64K) << 48;
        break;

    default:
        break;
    }
    return result;
}

static uint64_t table_entry_addr(GICv3ITSState *s, TableDesc *td,
                                 uint32_t idx, MemTxResult *res)
{
    /*
     * Given a TableDesc describing one of the ITS in-guest-memory
     * tables and an index into it, return the guest address
     * corresponding to that table entry.
     * If there was a memory error reading the L1 table of an
     * indirect table, *res is set accordingly, and we return -1.
     * If the L1 table entry is marked not valid, we return -1 with
     * *res set to MEMTX_OK.
     *
     * The specification defines the format of level 1 entries of a
     * 2-level table, but the format of level 2 entries and the format
     * of flat-mapped tables is IMPDEF.
     */
    AddressSpace *as = &s->gicv3->dma_as;
    uint32_t l2idx;
    uint64_t l2;
    uint32_t num_l2_entries;

    *res = MEMTX_OK;

    if (!td->indirect) {
        /* Single level table */
        return td->base_addr + idx * td->entry_sz;
    }

    /* Two level table */
    l2idx = idx / (td->page_sz / L1TABLE_ENTRY_SIZE);

    l2 = address_space_ldq_le(as,
                              td->base_addr + (l2idx * L1TABLE_ENTRY_SIZE),
                              MEMTXATTRS_UNSPECIFIED, res);
    if (*res != MEMTX_OK) {
        return -1;
    }
    if (!(l2 & L2_TABLE_VALID_MASK)) {
        return -1;
    }

    num_l2_entries = td->page_sz / td->entry_sz;
    return (l2 & ((1ULL << 51) - 1)) + (idx % num_l2_entries) * td->entry_sz;
}

/*
 * Read the Collection Table entry at index @icid. On success (including
 * successfully determining that there is no valid CTE for this index),
 * we return MEMTX_OK and populate the CTEntry struct @cte accordingly.
 * If there is an error reading memory then we return the error code.
 */
static MemTxResult get_cte(GICv3ITSState *s, uint16_t icid, CTEntry *cte)
{
    AddressSpace *as = &s->gicv3->dma_as;
    MemTxResult res = MEMTX_OK;
    uint64_t entry_addr = table_entry_addr(s, &s->ct, icid, &res);
    uint64_t cteval;

    if (entry_addr == -1) {
        /* No L2 table entry, i.e. no valid CTE, or a memory error */
        cte->valid = false;
        goto out;
    }

    cteval = address_space_ldq_le(as, entry_addr, MEMTXATTRS_UNSPECIFIED, &res);
    if (res != MEMTX_OK) {
        goto out;
    }
    cte->valid = FIELD_EX64(cteval, CTE, VALID);
    cte->rdbase = FIELD_EX64(cteval, CTE, RDBASE);
out:
    if (res != MEMTX_OK) {
        trace_gicv3_its_cte_read_fault(icid);
    } else {
        trace_gicv3_its_cte_read(icid, cte->valid, cte->rdbase);
    }
    return res;
}

/*
 * Update the Interrupt Table entry at index @evinted in the table specified
 * by the dte @dte. Returns true on success, false if there was a memory
 * access error.
 */
static bool update_ite(GICv3ITSState *s, uint32_t eventid, const DTEntry *dte,
                       const ITEntry *ite)
{
    AddressSpace *as = &s->gicv3->dma_as;
    MemTxResult res = MEMTX_OK;
    hwaddr iteaddr = dte->ittaddr + eventid * ITS_ITT_ENTRY_SIZE;
    uint64_t itel = 0;
    uint32_t iteh = 0;

    trace_gicv3_its_ite_write(dte->ittaddr, eventid, ite->valid,
                              ite->inttype, ite->intid, ite->icid,
                              ite->vpeid, ite->doorbell);

    if (ite->valid) {
        itel = FIELD_DP64(itel, ITE_L, VALID, 1);
        itel = FIELD_DP64(itel, ITE_L, INTTYPE, ite->inttype);
        itel = FIELD_DP64(itel, ITE_L, INTID, ite->intid);
        itel = FIELD_DP64(itel, ITE_L, ICID, ite->icid);
        itel = FIELD_DP64(itel, ITE_L, VPEID, ite->vpeid);
        iteh = FIELD_DP32(iteh, ITE_H, DOORBELL, ite->doorbell);
    }

    address_space_stq_le(as, iteaddr, itel, MEMTXATTRS_UNSPECIFIED, &res);
    if (res != MEMTX_OK) {
        return false;
    }
    address_space_stl_le(as, iteaddr + 8, iteh, MEMTXATTRS_UNSPECIFIED, &res);
    return res == MEMTX_OK;
}

/*
 * Read the Interrupt Table entry at index @eventid from the table specified
 * by the DTE @dte. On success, we return MEMTX_OK and populate the ITEntry
 * struct @ite accordingly. If there is an error reading memory then we return
 * the error code.
 */
static MemTxResult get_ite(GICv3ITSState *s, uint32_t eventid,
                           const DTEntry *dte, ITEntry *ite)
{
    AddressSpace *as = &s->gicv3->dma_as;
    MemTxResult res = MEMTX_OK;
    uint64_t itel;
    uint32_t iteh;
    hwaddr iteaddr = dte->ittaddr + eventid * ITS_ITT_ENTRY_SIZE;

    itel = address_space_ldq_le(as, iteaddr, MEMTXATTRS_UNSPECIFIED, &res);
    if (res != MEMTX_OK) {
        trace_gicv3_its_ite_read_fault(dte->ittaddr, eventid);
        return res;
    }

    iteh = address_space_ldl_le(as, iteaddr + 8, MEMTXATTRS_UNSPECIFIED, &res);
    if (res != MEMTX_OK) {
        trace_gicv3_its_ite_read_fault(dte->ittaddr, eventid);
        return res;
    }

    ite->valid = FIELD_EX64(itel, ITE_L, VALID);
    ite->inttype = FIELD_EX64(itel, ITE_L, INTTYPE);
    ite->intid = FIELD_EX64(itel, ITE_L, INTID);
    ite->icid = FIELD_EX64(itel, ITE_L, ICID);
    ite->vpeid = FIELD_EX64(itel, ITE_L, VPEID);
    ite->doorbell = FIELD_EX64(iteh, ITE_H, DOORBELL);
    trace_gicv3_its_ite_read(dte->ittaddr, eventid, ite->valid,
                             ite->inttype, ite->intid, ite->icid,
                             ite->vpeid, ite->doorbell);
    return MEMTX_OK;
}

/*
 * Read the Device Table entry at index @devid. On success (including
 * successfully determining that there is no valid DTE for this index),
 * we return MEMTX_OK and populate the DTEntry struct accordingly.
 * If there is an error reading memory then we return the error code.
 */
static MemTxResult get_dte(GICv3ITSState *s, uint32_t devid, DTEntry *dte)
{
    MemTxResult res = MEMTX_OK;
    AddressSpace *as = &s->gicv3->dma_as;
    uint64_t entry_addr = table_entry_addr(s, &s->dt, devid, &res);
    uint64_t dteval;

    if (entry_addr == -1) {
        /* No L2 table entry, i.e. no valid DTE, or a memory error */
        dte->valid = false;
        goto out;
    }
    dteval = address_space_ldq_le(as, entry_addr, MEMTXATTRS_UNSPECIFIED, &res);
    if (res != MEMTX_OK) {
        goto out;
    }
    dte->valid = FIELD_EX64(dteval, DTE, VALID);
    dte->size = FIELD_EX64(dteval, DTE, SIZE);
    /* DTE word field stores bits [51:8] of the ITT address */
    dte->ittaddr = FIELD_EX64(dteval, DTE, ITTADDR) << ITTADDR_SHIFT;
out:
    if (res != MEMTX_OK) {
        trace_gicv3_its_dte_read_fault(devid);
    } else {
        trace_gicv3_its_dte_read(devid, dte->valid, dte->size, dte->ittaddr);
    }
    return res;
}

/*
 * Read the vPE Table entry at index @vpeid. On success (including
 * successfully determining that there is no valid entry for this index),
 * we return MEMTX_OK and populate the VTEntry struct accordingly.
 * If there is an error reading memory then we return the error code.
 */
static MemTxResult get_vte(GICv3ITSState *s, uint32_t vpeid, VTEntry *vte)
{
    MemTxResult res = MEMTX_OK;
    AddressSpace *as = &s->gicv3->dma_as;
    uint64_t entry_addr = table_entry_addr(s, &s->vpet, vpeid, &res);
    uint64_t vteval;

    if (entry_addr == -1) {
        /* No L2 table entry, i.e. no valid VTE, or a memory error */
        vte->valid = false;
        goto out;
    }
    vteval = address_space_ldq_le(as, entry_addr, MEMTXATTRS_UNSPECIFIED, &res);
    if (res != MEMTX_OK) {
        goto out;
    }
    vte->valid = FIELD_EX64(vteval, VTE, VALID);
    vte->vptsize = FIELD_EX64(vteval, VTE, VPTSIZE);
    vte->vptaddr = FIELD_EX64(vteval, VTE, VPTADDR);
    vte->rdbase = FIELD_EX64(vteval, VTE, RDBASE);
out:
    if (res != MEMTX_OK) {
        trace_gicv3_its_vte_read_fault(vpeid);
    } else {
        trace_gicv3_its_vte_read(vpeid, vte->valid, vte->vptsize,
                                 vte->vptaddr, vte->rdbase);
    }
    return res;
}

/*
 * Given a (DeviceID, EventID), look up the corresponding ITE, including
 * checking for the various invalid-value cases. If we find a valid ITE,
 * fill in @ite and @dte and return CMD_CONTINUE_OK. Otherwise return
 * CMD_STALL or CMD_CONTINUE as appropriate (and the contents of @ite
 * should not be relied on).
 *
 * The string @who is purely for the LOG_GUEST_ERROR messages,
 * and should indicate the name of the calling function or similar.
 */
static ItsCmdResult lookup_ite(GICv3ITSState *s, const char *who,
                               uint32_t devid, uint32_t eventid, ITEntry *ite,
                               DTEntry *dte)
{
    uint64_t num_eventids;

    if (devid >= s->dt.num_entries) {
        qemu_log_mask(LOG_GUEST_ERROR,
                      "%s: invalid command attributes: devid %d>=%d",
                      who, devid, s->dt.num_entries);
        return CMD_CONTINUE;
    }

    if (get_dte(s, devid, dte) != MEMTX_OK) {
        return CMD_STALL;
    }
    if (!dte->valid) {
        qemu_log_mask(LOG_GUEST_ERROR,
                      "%s: invalid command attributes: "
                      "invalid dte for %d\n", who, devid);
        return CMD_CONTINUE;
    }

    num_eventids = 1ULL << (dte->size + 1);
    if (eventid >= num_eventids) {
        qemu_log_mask(LOG_GUEST_ERROR,
                      "%s: invalid command attributes: eventid %d >= %"
                      PRId64 "\n", who, eventid, num_eventids);
        return CMD_CONTINUE;
    }

    if (get_ite(s, eventid, dte, ite) != MEMTX_OK) {
        return CMD_STALL;
    }

    if (!ite->valid) {
        qemu_log_mask(LOG_GUEST_ERROR,
                      "%s: invalid command attributes: invalid ITE\n", who);
        return CMD_CONTINUE;
    }

    return CMD_CONTINUE_OK;
}

/*
 * Given an ICID, look up the corresponding CTE, including checking for various
 * invalid-value cases. If we find a valid CTE, fill in @cte and return
 * CMD_CONTINUE_OK; otherwise return CMD_STALL or CMD_CONTINUE (and the
 * contents of @cte should not be relied on).
 *
 * The string @who is purely for the LOG_GUEST_ERROR messages,
 * and should indicate the name of the calling function or similar.
 */
static ItsCmdResult lookup_cte(GICv3ITSState *s, const char *who,
                               uint32_t icid, CTEntry *cte)
{
    if (icid >= s->ct.num_entries) {
        qemu_log_mask(LOG_GUEST_ERROR, "%s: invalid ICID 0x%x\n", who, icid);
        return CMD_CONTINUE;
    }
    if (get_cte(s, icid, cte) != MEMTX_OK) {
        return CMD_STALL;
    }
    if (!cte->valid) {
        qemu_log_mask(LOG_GUEST_ERROR, "%s: invalid CTE\n", who);
        return CMD_CONTINUE;
    }
    if (cte->rdbase >= s->gicv3->num_cpu) {
        return CMD_CONTINUE;
    }
    return CMD_CONTINUE_OK;
}

/*
 * Given a VPEID, look up the corresponding VTE, including checking
 * for various invalid-value cases. if we find a valid VTE, fill in @vte
 * and return CMD_CONTINUE_OK; otherwise return CMD_STALL or CMD_CONTINUE
 * (and the contents of @vte should not be relied on).
 *
 * The string @who is purely for the LOG_GUEST_ERROR messages,
 * and should indicate the name of the calling function or similar.
 */
static ItsCmdResult lookup_vte(GICv3ITSState *s, const char *who,
                               uint32_t vpeid, VTEntry *vte)
{
    if (vpeid >= s->vpet.num_entries) {
        qemu_log_mask(LOG_GUEST_ERROR, "%s: invalid VPEID 0x%x\n", who, vpeid);
        return CMD_CONTINUE;
    }

    if (get_vte(s, vpeid, vte) != MEMTX_OK) {
        return CMD_STALL;
    }
    if (!vte->valid) {
        qemu_log_mask(LOG_GUEST_ERROR,
                      "%s: invalid VTE for VPEID 0x%x\n", who, vpeid);
        return CMD_CONTINUE;
    }

    if (vte->rdbase >= s->gicv3->num_cpu) {
        return CMD_CONTINUE;
    }
    return CMD_CONTINUE_OK;
}

static ItsCmdResult process_its_cmd_phys(GICv3ITSState *s, const ITEntry *ite,
                                         int irqlevel)
{
    CTEntry cte;
    ItsCmdResult cmdres;

    cmdres = lookup_cte(s, __func__, ite->icid, &cte);
    if (cmdres != CMD_CONTINUE_OK) {
        return cmdres;
    }
    gicv3_redist_process_lpi(&s->gicv3->cpu[cte.rdbase], ite->intid, irqlevel);
    return CMD_CONTINUE_OK;
}

static ItsCmdResult process_its_cmd_virt(GICv3ITSState *s, const ITEntry *ite,
                                         int irqlevel)
{
    VTEntry vte;
    ItsCmdResult cmdres;

    cmdres = lookup_vte(s, __func__, ite->vpeid, &vte);
    if (cmdres != CMD_CONTINUE_OK) {
        return cmdres;
    }

    if (!intid_in_lpi_range(ite->intid) ||
        ite->intid >= (1ULL << (vte.vptsize + 1))) {
        qemu_log_mask(LOG_GUEST_ERROR, "%s: intid 0x%x out of range\n",
                      __func__, ite->intid);
        return CMD_CONTINUE;
    }

    /*
     * For QEMU the actual pending of the vLPI is handled in the
     * redistributor code
     */
    gicv3_redist_process_vlpi(&s->gicv3->cpu[vte.rdbase], ite->intid,
                              vte.vptaddr << 16, ite->doorbell, irqlevel);
    return CMD_CONTINUE_OK;
}

/*
 * This function handles the processing of following commands based on
 * the ItsCmdType parameter passed:-
 * 1. triggering of lpi interrupt translation via ITS INT command
 * 2. triggering of lpi interrupt translation via gits_translater register
 * 3. handling of ITS CLEAR command
 * 4. handling of ITS DISCARD command
 */
static ItsCmdResult do_process_its_cmd(GICv3ITSState *s, uint32_t devid,
                                       uint32_t eventid, ItsCmdType cmd)
{
    DTEntry dte;
    ITEntry ite;
    ItsCmdResult cmdres;
    int irqlevel;

    cmdres = lookup_ite(s, __func__, devid, eventid, &ite, &dte);
    if (cmdres != CMD_CONTINUE_OK) {
        return cmdres;
    }

    irqlevel = (cmd == CLEAR || cmd == DISCARD) ? 0 : 1;

    switch (ite.inttype) {
    case ITE_INTTYPE_PHYSICAL:
        cmdres = process_its_cmd_phys(s, &ite, irqlevel);
        break;
    case ITE_INTTYPE_VIRTUAL:
        if (!its_feature_virtual(s)) {
            /* Can't happen unless guest is illegally writing to table memory */
            qemu_log_mask(LOG_GUEST_ERROR,
                          "%s: invalid type %d in ITE (table corrupted?)\n",
                          __func__, ite.inttype);
            return CMD_CONTINUE;
        }
        cmdres = process_its_cmd_virt(s, &ite, irqlevel);
        break;
    default:
        g_assert_not_reached();
    }

    if (cmdres == CMD_CONTINUE_OK && cmd == DISCARD) {
        ITEntry ite = {};
        /* remove mapping from interrupt translation table */
        ite.valid = false;
        return update_ite(s, eventid, &dte, &ite) ? CMD_CONTINUE_OK : CMD_STALL;
    }
    return CMD_CONTINUE_OK;
}

static ItsCmdResult process_its_cmd(GICv3ITSState *s, const uint64_t *cmdpkt,
                                    ItsCmdType cmd)
{
    uint32_t devid, eventid;

    devid = (cmdpkt[0] & DEVID_MASK) >> DEVID_SHIFT;
    eventid = cmdpkt[1] & EVENTID_MASK;
    switch (cmd) {
    case INTERRUPT:
        trace_gicv3_its_cmd_int(devid, eventid);
        break;
    case CLEAR:
        trace_gicv3_its_cmd_clear(devid, eventid);
        break;
    case DISCARD:
        trace_gicv3_its_cmd_discard(devid, eventid);
        break;
    default:
        g_assert_not_reached();
    }
    return do_process_its_cmd(s, devid, eventid, cmd);
}

static ItsCmdResult process_mapti(GICv3ITSState *s, const uint64_t *cmdpkt,
                                  bool ignore_pInt)
{
    uint32_t devid, eventid;
    uint32_t pIntid = 0;
    uint64_t num_eventids;
    uint16_t icid = 0;
    DTEntry dte;
    ITEntry ite;

    devid = (cmdpkt[0] & DEVID_MASK) >> DEVID_SHIFT;
    eventid = cmdpkt[1] & EVENTID_MASK;
    icid = cmdpkt[2] & ICID_MASK;

    if (ignore_pInt) {
        pIntid = eventid;
        trace_gicv3_its_cmd_mapi(devid, eventid, icid);
    } else {
        pIntid = (cmdpkt[1] & pINTID_MASK) >> pINTID_SHIFT;
        trace_gicv3_its_cmd_mapti(devid, eventid, icid, pIntid);
    }

    if (devid >= s->dt.num_entries) {
        qemu_log_mask(LOG_GUEST_ERROR,
                      "%s: invalid command attributes: devid %d>=%d",
                      __func__, devid, s->dt.num_entries);
        return CMD_CONTINUE;
    }

    if (get_dte(s, devid, &dte) != MEMTX_OK) {
        return CMD_STALL;
    }
    num_eventids = 1ULL << (dte.size + 1);

    if (icid >= s->ct.num_entries) {
        qemu_log_mask(LOG_GUEST_ERROR,
                      "%s: invalid ICID 0x%x >= 0x%x\n",
                      __func__, icid, s->ct.num_entries);
        return CMD_CONTINUE;
    }

    if (!dte.valid) {
        qemu_log_mask(LOG_GUEST_ERROR,
                      "%s: no valid DTE for devid 0x%x\n", __func__, devid);
        return CMD_CONTINUE;
    }

    if (eventid >= num_eventids) {
        qemu_log_mask(LOG_GUEST_ERROR,
                      "%s: invalid event ID 0x%x >= 0x%" PRIx64 "\n",
                      __func__, eventid, num_eventids);
        return CMD_CONTINUE;
    }

    if (!intid_in_lpi_range(pIntid)) {
        qemu_log_mask(LOG_GUEST_ERROR,
                      "%s: invalid interrupt ID 0x%x\n", __func__, pIntid);
        return CMD_CONTINUE;
    }

    /* add ite entry to interrupt translation table */
    ite.valid = true;
    ite.inttype = ITE_INTTYPE_PHYSICAL;
    ite.intid = pIntid;
    ite.icid = icid;
    ite.doorbell = INTID_SPURIOUS;
    ite.vpeid = 0;
    return update_ite(s, eventid, &dte, &ite) ? CMD_CONTINUE_OK : CMD_STALL;
}

static ItsCmdResult process_vmapti(GICv3ITSState *s, const uint64_t *cmdpkt,
                                   bool ignore_vintid)
{
    uint32_t devid, eventid, vintid, doorbell, vpeid;
    uint32_t num_eventids;
    DTEntry dte;
    ITEntry ite;

    if (!its_feature_virtual(s)) {
        return CMD_CONTINUE;
    }

    devid = FIELD_EX64(cmdpkt[0], VMAPTI_0, DEVICEID);
    eventid = FIELD_EX64(cmdpkt[1], VMAPTI_1, EVENTID);
    vpeid = FIELD_EX64(cmdpkt[1], VMAPTI_1, VPEID);
    doorbell = FIELD_EX64(cmdpkt[2], VMAPTI_2, DOORBELL);
    if (ignore_vintid) {
        vintid = eventid;
        trace_gicv3_its_cmd_vmapi(devid, eventid, vpeid, doorbell);
    } else {
        vintid = FIELD_EX64(cmdpkt[2], VMAPTI_2, VINTID);
        trace_gicv3_its_cmd_vmapti(devid, eventid, vpeid, vintid, doorbell);
    }

    if (devid >= s->dt.num_entries) {
        qemu_log_mask(LOG_GUEST_ERROR,
                      "%s: invalid DeviceID 0x%x (must be less than 0x%x)\n",
                      __func__, devid, s->dt.num_entries);
        return CMD_CONTINUE;
    }

    if (get_dte(s, devid, &dte) != MEMTX_OK) {
        return CMD_STALL;
    }

    if (!dte.valid) {
        qemu_log_mask(LOG_GUEST_ERROR,
                      "%s: no entry in device table for DeviceID 0x%x\n",
                      __func__, devid);
        return CMD_CONTINUE;
    }

    num_eventids = 1ULL << (dte.size + 1);

    if (eventid >= num_eventids) {
        qemu_log_mask(LOG_GUEST_ERROR,
                      "%s: EventID 0x%x too large for DeviceID 0x%x "
                      "(must be less than 0x%x)\n",
                      __func__, eventid, devid, num_eventids);
        return CMD_CONTINUE;
    }
    if (!intid_in_lpi_range(vintid)) {
        qemu_log_mask(LOG_GUEST_ERROR,
                      "%s: VIntID 0x%x not a valid LPI\n",
                      __func__, vintid);
        return CMD_CONTINUE;
    }
    if (!valid_doorbell(doorbell)) {
        qemu_log_mask(LOG_GUEST_ERROR,
                      "%s: Doorbell %d not 1023 and not a valid LPI\n",
                      __func__, doorbell);
        return CMD_CONTINUE;
    }
    if (vpeid >= s->vpet.num_entries) {
        qemu_log_mask(LOG_GUEST_ERROR,
                      "%s: VPEID 0x%x out of range (must be less than 0x%x)\n",
                      __func__, vpeid, s->vpet.num_entries);
        return CMD_CONTINUE;
    }
    /* add ite entry to interrupt translation table */
    ite.valid = true;
    ite.inttype = ITE_INTTYPE_VIRTUAL;
    ite.intid = vintid;
    ite.icid = 0;
    ite.doorbell = doorbell;
    ite.vpeid = vpeid;
    return update_ite(s, eventid, &dte, &ite) ? CMD_CONTINUE_OK : CMD_STALL;
}

/*
 * Update the Collection Table entry for @icid to @cte. Returns true
 * on success, false if there was a memory access error.
 */
static bool update_cte(GICv3ITSState *s, uint16_t icid, const CTEntry *cte)
{
    AddressSpace *as = &s->gicv3->dma_as;
    uint64_t entry_addr;
    uint64_t cteval = 0;
    MemTxResult res = MEMTX_OK;

    trace_gicv3_its_cte_write(icid, cte->valid, cte->rdbase);

    if (cte->valid) {
        /* add mapping entry to collection table */
        cteval = FIELD_DP64(cteval, CTE, VALID, 1);
        cteval = FIELD_DP64(cteval, CTE, RDBASE, cte->rdbase);
    }

    entry_addr = table_entry_addr(s, &s->ct, icid, &res);
    if (res != MEMTX_OK) {
        /* memory access error: stall */
        return false;
    }
    if (entry_addr == -1) {
        /* No L2 table for this index: discard write and continue */
        return true;
    }

    address_space_stq_le(as, entry_addr, cteval, MEMTXATTRS_UNSPECIFIED, &res);
    return res == MEMTX_OK;
}

static ItsCmdResult process_mapc(GICv3ITSState *s, const uint64_t *cmdpkt)
{
    uint16_t icid;
    CTEntry cte;

    icid = cmdpkt[2] & ICID_MASK;
    cte.valid = cmdpkt[2] & CMD_FIELD_VALID_MASK;
    if (cte.valid) {
        cte.rdbase = (cmdpkt[2] & R_MAPC_RDBASE_MASK) >> R_MAPC_RDBASE_SHIFT;
        cte.rdbase &= RDBASE_PROCNUM_MASK;
    } else {
        cte.rdbase = 0;
    }
    trace_gicv3_its_cmd_mapc(icid, cte.rdbase, cte.valid);

    if (icid >= s->ct.num_entries) {
        qemu_log_mask(LOG_GUEST_ERROR, "ITS MAPC: invalid ICID 0x%x\n", icid);
        return CMD_CONTINUE;
    }
    if (cte.valid && cte.rdbase >= s->gicv3->num_cpu) {
        qemu_log_mask(LOG_GUEST_ERROR,
                      "ITS MAPC: invalid RDBASE %u\n", cte.rdbase);
        return CMD_CONTINUE;
    }

    return update_cte(s, icid, &cte) ? CMD_CONTINUE_OK : CMD_STALL;
}

/*
 * Update the Device Table entry for @devid to @dte. Returns true
 * on success, false if there was a memory access error.
 */
static bool update_dte(GICv3ITSState *s, uint32_t devid, const DTEntry *dte)
{
    AddressSpace *as = &s->gicv3->dma_as;
    uint64_t entry_addr;
    uint64_t dteval = 0;
    MemTxResult res = MEMTX_OK;

    trace_gicv3_its_dte_write(devid, dte->valid, dte->size, dte->ittaddr);

    if (dte->valid) {
        /* add mapping entry to device table */
        dteval = FIELD_DP64(dteval, DTE, VALID, 1);
        dteval = FIELD_DP64(dteval, DTE, SIZE, dte->size);
        dteval = FIELD_DP64(dteval, DTE, ITTADDR, dte->ittaddr);
    }

    entry_addr = table_entry_addr(s, &s->dt, devid, &res);
    if (res != MEMTX_OK) {
        /* memory access error: stall */
        return false;
    }
    if (entry_addr == -1) {
        /* No L2 table for this index: discard write and continue */
        return true;
    }
    address_space_stq_le(as, entry_addr, dteval, MEMTXATTRS_UNSPECIFIED, &res);
    return res == MEMTX_OK;
}

static ItsCmdResult process_mapd(GICv3ITSState *s, const uint64_t *cmdpkt)
{
    uint32_t devid;
    DTEntry dte;

    devid = (cmdpkt[0] & DEVID_MASK) >> DEVID_SHIFT;
    dte.size = cmdpkt[1] & SIZE_MASK;
    dte.ittaddr = (cmdpkt[2] & ITTADDR_MASK) >> ITTADDR_SHIFT;
    dte.valid = cmdpkt[2] & CMD_FIELD_VALID_MASK;

    trace_gicv3_its_cmd_mapd(devid, dte.size, dte.ittaddr, dte.valid);

    if (devid >= s->dt.num_entries) {
        qemu_log_mask(LOG_GUEST_ERROR,
                      "ITS MAPD: invalid device ID field 0x%x >= 0x%x\n",
                      devid, s->dt.num_entries);
        return CMD_CONTINUE;
    }

    if (dte.size > FIELD_EX64(s->typer, GITS_TYPER, IDBITS)) {
        qemu_log_mask(LOG_GUEST_ERROR,
                      "ITS MAPD: invalid size %d\n", dte.size);
        return CMD_CONTINUE;
    }

    return update_dte(s, devid, &dte) ? CMD_CONTINUE_OK : CMD_STALL;
}

static ItsCmdResult process_movall(GICv3ITSState *s, const uint64_t *cmdpkt)
{
    uint64_t rd1, rd2;

    rd1 = FIELD_EX64(cmdpkt[2], MOVALL_2, RDBASE1);
    rd2 = FIELD_EX64(cmdpkt[3], MOVALL_3, RDBASE2);

    trace_gicv3_its_cmd_movall(rd1, rd2);

    if (rd1 >= s->gicv3->num_cpu) {
        qemu_log_mask(LOG_GUEST_ERROR,
                      "%s: RDBASE1 %" PRId64
                      " out of range (must be less than %d)\n",
                      __func__, rd1, s->gicv3->num_cpu);
        return CMD_CONTINUE;
    }
    if (rd2 >= s->gicv3->num_cpu) {
        qemu_log_mask(LOG_GUEST_ERROR,
                      "%s: RDBASE2 %" PRId64
                      " out of range (must be less than %d)\n",
                      __func__, rd2, s->gicv3->num_cpu);
        return CMD_CONTINUE;
    }

    if (rd1 == rd2) {
        /* Move to same target must succeed as a no-op */
        return CMD_CONTINUE_OK;
    }

    /* Move all pending LPIs from redistributor 1 to redistributor 2 */
    gicv3_redist_movall_lpis(&s->gicv3->cpu[rd1], &s->gicv3->cpu[rd2]);

    return CMD_CONTINUE_OK;
}

static ItsCmdResult process_movi(GICv3ITSState *s, const uint64_t *cmdpkt)
{
    uint32_t devid, eventid;
    uint16_t new_icid;
    DTEntry dte;
    CTEntry old_cte, new_cte;
    ITEntry old_ite;
    ItsCmdResult cmdres;

    devid = FIELD_EX64(cmdpkt[0], MOVI_0, DEVICEID);
    eventid = FIELD_EX64(cmdpkt[1], MOVI_1, EVENTID);
    new_icid = FIELD_EX64(cmdpkt[2], MOVI_2, ICID);

    trace_gicv3_its_cmd_movi(devid, eventid, new_icid);

    cmdres = lookup_ite(s, __func__, devid, eventid, &old_ite, &dte);
    if (cmdres != CMD_CONTINUE_OK) {
        return cmdres;
    }

    if (old_ite.inttype != ITE_INTTYPE_PHYSICAL) {
        qemu_log_mask(LOG_GUEST_ERROR,
                      "%s: invalid command attributes: invalid ITE\n",
                      __func__);
        return CMD_CONTINUE;
    }

    cmdres = lookup_cte(s, __func__, old_ite.icid, &old_cte);
    if (cmdres != CMD_CONTINUE_OK) {
        return cmdres;
    }
    cmdres = lookup_cte(s, __func__, new_icid, &new_cte);
    if (cmdres != CMD_CONTINUE_OK) {
        return cmdres;
    }

    if (old_cte.rdbase != new_cte.rdbase) {
        /* Move the LPI from the old redistributor to the new one */
        gicv3_redist_mov_lpi(&s->gicv3->cpu[old_cte.rdbase],
                             &s->gicv3->cpu[new_cte.rdbase],
                             old_ite.intid);
    }

    /* Update the ICID field in the interrupt translation table entry */
    old_ite.icid = new_icid;
    return update_ite(s, eventid, &dte, &old_ite) ? CMD_CONTINUE_OK : CMD_STALL;
}

/*
 * Update the vPE Table entry at index @vpeid with the entry @vte.
 * Returns true on success, false if there was a memory access error.
 */
static bool update_vte(GICv3ITSState *s, uint32_t vpeid, const VTEntry *vte)
{
    AddressSpace *as = &s->gicv3->dma_as;
    uint64_t entry_addr;
    uint64_t vteval = 0;
    MemTxResult res = MEMTX_OK;

    trace_gicv3_its_vte_write(vpeid, vte->valid, vte->vptsize, vte->vptaddr,
                              vte->rdbase);

    if (vte->valid) {
        vteval = FIELD_DP64(vteval, VTE, VALID, 1);
        vteval = FIELD_DP64(vteval, VTE, VPTSIZE, vte->vptsize);
        vteval = FIELD_DP64(vteval, VTE, VPTADDR, vte->vptaddr);
        vteval = FIELD_DP64(vteval, VTE, RDBASE, vte->rdbase);
    }

    entry_addr = table_entry_addr(s, &s->vpet, vpeid, &res);
    if (res != MEMTX_OK) {
        return false;
    }
    if (entry_addr == -1) {
        /* No L2 table for this index: discard write and continue */
        return true;
    }
    address_space_stq_le(as, entry_addr, vteval, MEMTXATTRS_UNSPECIFIED, &res);
    return res == MEMTX_OK;
}

static ItsCmdResult process_vmapp(GICv3ITSState *s, const uint64_t *cmdpkt)
{
    VTEntry vte;
    uint32_t vpeid;

    if (!its_feature_virtual(s)) {
        return CMD_CONTINUE;
    }

    vpeid = FIELD_EX64(cmdpkt[1], VMAPP_1, VPEID);
    vte.rdbase = FIELD_EX64(cmdpkt[2], VMAPP_2, RDBASE);
    vte.valid = FIELD_EX64(cmdpkt[2], VMAPP_2, V);
    vte.vptsize = FIELD_EX64(cmdpkt[3], VMAPP_3, VPTSIZE);
    vte.vptaddr = FIELD_EX64(cmdpkt[3], VMAPP_3, VPTADDR);

    trace_gicv3_its_cmd_vmapp(vpeid, vte.rdbase, vte.valid,
                              vte.vptaddr, vte.vptsize);

    /*
     * For GICv4.0 the VPT_size field is only 5 bits, whereas we
     * define our field macros to include the full GICv4.1 8 bits.
     * The range check on VPT_size will catch the cases where
     * the guest set the RES0-in-GICv4.0 bits [7:6].
     */
    if (vte.vptsize > FIELD_EX64(s->typer, GITS_TYPER, IDBITS)) {
        qemu_log_mask(LOG_GUEST_ERROR,
                      "%s: invalid VPT_size 0x%x\n", __func__, vte.vptsize);
        return CMD_CONTINUE;
    }

    if (vte.valid && vte.rdbase >= s->gicv3->num_cpu) {
        qemu_log_mask(LOG_GUEST_ERROR,
                      "%s: invalid rdbase 0x%x\n", __func__, vte.rdbase);
        return CMD_CONTINUE;
    }

    if (vpeid >= s->vpet.num_entries) {
        qemu_log_mask(LOG_GUEST_ERROR,
                      "%s: VPEID 0x%x out of range (must be less than 0x%x)\n",
                      __func__, vpeid, s->vpet.num_entries);
        return CMD_CONTINUE;
    }

    return update_vte(s, vpeid, &vte) ? CMD_CONTINUE_OK : CMD_STALL;
}

typedef struct VmovpCallbackData {
    uint64_t rdbase;
    uint32_t vpeid;
    /*
     * Overall command result. If more than one callback finds an
     * error, STALL beats CONTINUE.
     */
    ItsCmdResult result;
} VmovpCallbackData;

static void vmovp_callback(gpointer data, gpointer opaque)
{
    /*
     * This function is called to update the VPEID field in a VPE
     * table entry for this ITS. This might be because of a VMOVP
     * command executed on any ITS that is connected to the same GIC
     * as this ITS.  We need to read the VPE table entry for the VPEID
     * and update its RDBASE field.
     */
    GICv3ITSState *s = data;
    VmovpCallbackData *cbdata = opaque;
    VTEntry vte;
    ItsCmdResult cmdres;

    cmdres = lookup_vte(s, __func__, cbdata->vpeid, &vte);
    switch (cmdres) {
    case CMD_STALL:
        cbdata->result = CMD_STALL;
        return;
    case CMD_CONTINUE:
        if (cbdata->result != CMD_STALL) {
            cbdata->result = CMD_CONTINUE;
        }
        return;
    case CMD_CONTINUE_OK:
        break;
    }

    vte.rdbase = cbdata->rdbase;
    if (!update_vte(s, cbdata->vpeid, &vte)) {
        cbdata->result = CMD_STALL;
    }
}

static ItsCmdResult process_vmovp(GICv3ITSState *s, const uint64_t *cmdpkt)
{
    VmovpCallbackData cbdata;

    if (!its_feature_virtual(s)) {
        return CMD_CONTINUE;
    }

    cbdata.vpeid = FIELD_EX64(cmdpkt[1], VMOVP_1, VPEID);
    cbdata.rdbase = FIELD_EX64(cmdpkt[2], VMOVP_2, RDBASE);

    trace_gicv3_its_cmd_vmovp(cbdata.vpeid, cbdata.rdbase);

    if (cbdata.rdbase >= s->gicv3->num_cpu) {
        return CMD_CONTINUE;
    }

    /*
     * Our ITS implementation reports GITS_TYPER.VMOVP == 1, which means
     * that when the VMOVP command is executed on an ITS to change the
     * VPEID field in a VPE table entry the change must be propagated
     * to all the ITSes connected to the same GIC.
     */
    cbdata.result = CMD_CONTINUE_OK;
    gicv3_foreach_its(s->gicv3, vmovp_callback, &cbdata);
    return cbdata.result;
}

/*
 * Current implementation blocks until all
 * commands are processed
 */
static void process_cmdq(GICv3ITSState *s)
{
    uint32_t wr_offset = 0;
    uint32_t rd_offset = 0;
    uint32_t cq_offset = 0;
    AddressSpace *as = &s->gicv3->dma_as;
    uint8_t cmd;
    int i;

    if (!(s->ctlr & R_GITS_CTLR_ENABLED_MASK)) {
        return;
    }

    wr_offset = FIELD_EX64(s->cwriter, GITS_CWRITER, OFFSET);

    if (wr_offset >= s->cq.num_entries) {
        qemu_log_mask(LOG_GUEST_ERROR,
                      "%s: invalid write offset "
                      "%d\n", __func__, wr_offset);
        return;
    }

    rd_offset = FIELD_EX64(s->creadr, GITS_CREADR, OFFSET);

    if (rd_offset >= s->cq.num_entries) {
        qemu_log_mask(LOG_GUEST_ERROR,
                      "%s: invalid read offset "
                      "%d\n", __func__, rd_offset);
        return;
    }

    while (wr_offset != rd_offset) {
        ItsCmdResult result = CMD_CONTINUE_OK;
        void *hostmem;
        hwaddr buflen;
        uint64_t cmdpkt[GITS_CMDQ_ENTRY_WORDS];

        cq_offset = (rd_offset * GITS_CMDQ_ENTRY_SIZE);

        buflen = GITS_CMDQ_ENTRY_SIZE;
        hostmem = address_space_map(as, s->cq.base_addr + cq_offset,
                                    &buflen, false, MEMTXATTRS_UNSPECIFIED);
        if (!hostmem || buflen != GITS_CMDQ_ENTRY_SIZE) {
            if (hostmem) {
                address_space_unmap(as, hostmem, buflen, false, 0);
            }
            s->creadr = FIELD_DP64(s->creadr, GITS_CREADR, STALLED, 1);
            qemu_log_mask(LOG_GUEST_ERROR,
                          "%s: could not read command at 0x%" PRIx64 "\n",
                          __func__, s->cq.base_addr + cq_offset);
            break;
        }
        for (i = 0; i < ARRAY_SIZE(cmdpkt); i++) {
            cmdpkt[i] = ldq_le_p(hostmem + i * sizeof(uint64_t));
        }
        address_space_unmap(as, hostmem, buflen, false, 0);

        cmd = cmdpkt[0] & CMD_MASK;

        trace_gicv3_its_process_command(rd_offset, cmd);

        switch (cmd) {
        case GITS_CMD_INT:
            result = process_its_cmd(s, cmdpkt, INTERRUPT);
            break;
        case GITS_CMD_CLEAR:
            result = process_its_cmd(s, cmdpkt, CLEAR);
            break;
        case GITS_CMD_SYNC:
            /*
             * Current implementation makes a blocking synchronous call
             * for every command issued earlier, hence the internal state
             * is already consistent by the time SYNC command is executed.
             * Hence no further processing is required for SYNC command.
             */
            trace_gicv3_its_cmd_sync();
            break;
        case GITS_CMD_VSYNC:
            /*
             * VSYNC also is a nop, because our implementation is always
             * in sync.
             */
            if (!its_feature_virtual(s)) {
                result = CMD_CONTINUE;
                break;
            }
            trace_gicv3_its_cmd_vsync();
            break;
        case GITS_CMD_MAPD:
            result = process_mapd(s, cmdpkt);
            break;
        case GITS_CMD_MAPC:
            result = process_mapc(s, cmdpkt);
            break;
        case GITS_CMD_MAPTI:
            result = process_mapti(s, cmdpkt, false);
            break;
        case GITS_CMD_MAPI:
            result = process_mapti(s, cmdpkt, true);
            break;
        case GITS_CMD_DISCARD:
            result = process_its_cmd(s, cmdpkt, DISCARD);
            break;
        case GITS_CMD_INV:
        case GITS_CMD_INVALL:
            /*
             * Current implementation doesn't cache any ITS tables,
             * but the calculated lpi priority information. We only
             * need to trigger lpi priority re-calculation to be in
             * sync with LPI config table or pending table changes.
             */
            trace_gicv3_its_cmd_inv();
            for (i = 0; i < s->gicv3->num_cpu; i++) {
                gicv3_redist_update_lpi(&s->gicv3->cpu[i]);
            }
            break;
        case GITS_CMD_MOVI:
            result = process_movi(s, cmdpkt);
            break;
        case GITS_CMD_MOVALL:
            result = process_movall(s, cmdpkt);
            break;
        case GITS_CMD_VMAPTI:
            result = process_vmapti(s, cmdpkt, false);
            break;
        case GITS_CMD_VMAPI:
            result = process_vmapti(s, cmdpkt, true);
            break;
        case GITS_CMD_VMAPP:
            result = process_vmapp(s, cmdpkt);
            break;
        case GITS_CMD_VMOVP:
            result = process_vmovp(s, cmdpkt);
            break;
        default:
            trace_gicv3_its_cmd_unknown(cmd);
            break;
        }
        if (result != CMD_STALL) {
            /* CMD_CONTINUE or CMD_CONTINUE_OK */
            rd_offset++;
            rd_offset %= s->cq.num_entries;
            s->creadr = FIELD_DP64(s->creadr, GITS_CREADR, OFFSET, rd_offset);
        } else {
            /* CMD_STALL */
            s->creadr = FIELD_DP64(s->creadr, GITS_CREADR, STALLED, 1);
            qemu_log_mask(LOG_GUEST_ERROR,
                          "%s: 0x%x cmd processing failed, stalling\n",
                          __func__, cmd);
            break;
        }
    }
}

/*
 * This function extracts the ITS Device and Collection table specific
 * parameters (like base_addr, size etc) from GITS_BASER register.
 * It is called during ITS enable and also during post_load migration
 */
static void extract_table_params(GICv3ITSState *s)
{
    uint16_t num_pages = 0;
    uint8_t  page_sz_type;
    uint8_t type;
    uint32_t page_sz = 0;
    uint64_t value;

    for (int i = 0; i < 8; i++) {
        TableDesc *td;
        int idbits;

        value = s->baser[i];

        if (!value) {
            continue;
        }

        page_sz_type = FIELD_EX64(value, GITS_BASER, PAGESIZE);

        switch (page_sz_type) {
        case 0:
            page_sz = GITS_PAGE_SIZE_4K;
            break;

        case 1:
            page_sz = GITS_PAGE_SIZE_16K;
            break;

        case 2:
        case 3:
            page_sz = GITS_PAGE_SIZE_64K;
            break;

        default:
            g_assert_not_reached();
        }

        num_pages = FIELD_EX64(value, GITS_BASER, SIZE) + 1;

        type = FIELD_EX64(value, GITS_BASER, TYPE);

        switch (type) {
        case GITS_BASER_TYPE_DEVICE:
            td = &s->dt;
            idbits = FIELD_EX64(s->typer, GITS_TYPER, DEVBITS) + 1;
            break;
        case GITS_BASER_TYPE_COLLECTION:
            td = &s->ct;
            if (FIELD_EX64(s->typer, GITS_TYPER, CIL)) {
                idbits = FIELD_EX64(s->typer, GITS_TYPER, CIDBITS) + 1;
            } else {
                /* 16-bit CollectionId supported when CIL == 0 */
                idbits = 16;
            }
            break;
        case GITS_BASER_TYPE_VPE:
            td = &s->vpet;
            /*
             * For QEMU vPEIDs are always 16 bits. (GICv4.1 allows an
             * implementation to implement fewer bits and report this
             * via GICD_TYPER2.)
             */
            idbits = 16;
            break;
        default:
            /*
             * GITS_BASER<n>.TYPE is read-only, so GITS_BASER_RO_MASK
             * ensures we will only see type values corresponding to
             * the values set up in gicv3_its_reset().
             */
            g_assert_not_reached();
        }

        memset(td, 0, sizeof(*td));
        /*
         * If GITS_BASER<n>.Valid is 0 for any <n> then we will not process
         * interrupts. (GITS_TYPER.HCC is 0 for this implementation, so we
         * do not have a special case where the GITS_BASER<n>.Valid bit is 0
         * for the register corresponding to the Collection table but we
         * still have to process interrupts using non-memory-backed
         * Collection table entries.)
         * The specification makes it UNPREDICTABLE to enable the ITS without
         * marking each BASER<n> as valid. We choose to handle these as if
         * the table was zero-sized, so commands using the table will fail
         * and interrupts requested via GITS_TRANSLATER writes will be ignored.
         * This happens automatically by leaving the num_entries field at
         * zero, which will be caught by the bounds checks we have before
         * every table lookup anyway.
         */
        if (!FIELD_EX64(value, GITS_BASER, VALID)) {
            continue;
        }
        td->page_sz = page_sz;
        td->indirect = FIELD_EX64(value, GITS_BASER, INDIRECT);
        td->entry_sz = FIELD_EX64(value, GITS_BASER, ENTRYSIZE) + 1;
        td->base_addr = baser_base_addr(value, page_sz);
        if (!td->indirect) {
            td->num_entries = (num_pages * page_sz) / td->entry_sz;
        } else {
            td->num_entries = (((num_pages * page_sz) /
                                  L1TABLE_ENTRY_SIZE) *
                                 (page_sz / td->entry_sz));
        }
        td->num_entries = MIN(td->num_entries, 1ULL << idbits);
    }
}

static void extract_cmdq_params(GICv3ITSState *s)
{
    uint16_t num_pages = 0;
    uint64_t value = s->cbaser;

    num_pages = FIELD_EX64(value, GITS_CBASER, SIZE) + 1;

    memset(&s->cq, 0 , sizeof(s->cq));

    if (FIELD_EX64(value, GITS_CBASER, VALID)) {
        s->cq.num_entries = (num_pages * GITS_PAGE_SIZE_4K) /
                             GITS_CMDQ_ENTRY_SIZE;
        s->cq.base_addr = FIELD_EX64(value, GITS_CBASER, PHYADDR);
        s->cq.base_addr <<= R_GITS_CBASER_PHYADDR_SHIFT;
    }
}

static MemTxResult gicv3_its_translation_read(void *opaque, hwaddr offset,
                                              uint64_t *data, unsigned size,
                                              MemTxAttrs attrs)
{
    /*
     * GITS_TRANSLATER is write-only, and all other addresses
     * in the interrupt translation space frame are RES0.
     */
    *data = 0;
    return MEMTX_OK;
}

static MemTxResult gicv3_its_translation_write(void *opaque, hwaddr offset,
                                               uint64_t data, unsigned size,
                                               MemTxAttrs attrs)
{
    GICv3ITSState *s = (GICv3ITSState *)opaque;
    bool result = true;

    trace_gicv3_its_translation_write(offset, data, size, attrs.requester_id);

    switch (offset) {
    case GITS_TRANSLATER:
        if (s->ctlr & R_GITS_CTLR_ENABLED_MASK) {
            result = do_process_its_cmd(s, attrs.requester_id, data, NONE);
        }
        break;
    default:
        break;
    }

    if (result) {
        return MEMTX_OK;
    } else {
        return MEMTX_ERROR;
    }
}

static bool its_writel(GICv3ITSState *s, hwaddr offset,
                              uint64_t value, MemTxAttrs attrs)
{
    bool result = true;
    int index;

    switch (offset) {
    case GITS_CTLR:
        if (value & R_GITS_CTLR_ENABLED_MASK) {
            s->ctlr |= R_GITS_CTLR_ENABLED_MASK;
            extract_table_params(s);
            extract_cmdq_params(s);
            process_cmdq(s);
        } else {
            s->ctlr &= ~R_GITS_CTLR_ENABLED_MASK;
        }
        break;
    case GITS_CBASER:
        /*
         * IMPDEF choice:- GITS_CBASER register becomes RO if ITS is
         *                 already enabled
         */
        if (!(s->ctlr & R_GITS_CTLR_ENABLED_MASK)) {
            s->cbaser = deposit64(s->cbaser, 0, 32, value);
            s->creadr = 0;
        }
        break;
    case GITS_CBASER + 4:
        /*
         * IMPDEF choice:- GITS_CBASER register becomes RO if ITS is
         *                 already enabled
         */
        if (!(s->ctlr & R_GITS_CTLR_ENABLED_MASK)) {
            s->cbaser = deposit64(s->cbaser, 32, 32, value);
            s->creadr = 0;
        }
        break;
    case GITS_CWRITER:
        s->cwriter = deposit64(s->cwriter, 0, 32,
                               (value & ~R_GITS_CWRITER_RETRY_MASK));
        if (s->cwriter != s->creadr) {
            process_cmdq(s);
        }
        break;
    case GITS_CWRITER + 4:
        s->cwriter = deposit64(s->cwriter, 32, 32, value);
        break;
    case GITS_CREADR:
        if (s->gicv3->gicd_ctlr & GICD_CTLR_DS) {
            s->creadr = deposit64(s->creadr, 0, 32,
                                  (value & ~R_GITS_CREADR_STALLED_MASK));
        } else {
            /* RO register, ignore the write */
            qemu_log_mask(LOG_GUEST_ERROR,
                          "%s: invalid guest write to RO register at offset "
                          TARGET_FMT_plx "\n", __func__, offset);
        }
        break;
    case GITS_CREADR + 4:
        if (s->gicv3->gicd_ctlr & GICD_CTLR_DS) {
            s->creadr = deposit64(s->creadr, 32, 32, value);
        } else {
            /* RO register, ignore the write */
            qemu_log_mask(LOG_GUEST_ERROR,
                          "%s: invalid guest write to RO register at offset "
                          TARGET_FMT_plx "\n", __func__, offset);
        }
        break;
    case GITS_BASER ... GITS_BASER + 0x3f:
        /*
         * IMPDEF choice:- GITS_BASERn register becomes RO if ITS is
         *                 already enabled
         */
        if (!(s->ctlr & R_GITS_CTLR_ENABLED_MASK)) {
            index = (offset - GITS_BASER) / 8;

            if (s->baser[index] == 0) {
                /* Unimplemented GITS_BASERn: RAZ/WI */
                break;
            }
            if (offset & 7) {
                value <<= 32;
                value &= ~GITS_BASER_RO_MASK;
                s->baser[index] &= GITS_BASER_RO_MASK | MAKE_64BIT_MASK(0, 32);
                s->baser[index] |= value;
            } else {
                value &= ~GITS_BASER_RO_MASK;
                s->baser[index] &= GITS_BASER_RO_MASK | MAKE_64BIT_MASK(32, 32);
                s->baser[index] |= value;
            }
        }
        break;
    case GITS_IIDR:
    case GITS_IDREGS ... GITS_IDREGS + 0x2f:
        /* RO registers, ignore the write */
        qemu_log_mask(LOG_GUEST_ERROR,
                      "%s: invalid guest write to RO register at offset "
                      TARGET_FMT_plx "\n", __func__, offset);
        break;
    default:
        result = false;
        break;
    }
    return result;
}

static bool its_readl(GICv3ITSState *s, hwaddr offset,
                             uint64_t *data, MemTxAttrs attrs)
{
    bool result = true;
    int index;

    switch (offset) {
    case GITS_CTLR:
        *data = s->ctlr;
        break;
    case GITS_IIDR:
        *data = gicv3_iidr();
        break;
    case GITS_IDREGS ... GITS_IDREGS + 0x2f:
        /* ID registers */
        *data = gicv3_idreg(offset - GITS_IDREGS, GICV3_PIDR0_ITS);
        break;
    case GITS_TYPER:
        *data = extract64(s->typer, 0, 32);
        break;
    case GITS_TYPER + 4:
        *data = extract64(s->typer, 32, 32);
        break;
    case GITS_CBASER:
        *data = extract64(s->cbaser, 0, 32);
        break;
    case GITS_CBASER + 4:
        *data = extract64(s->cbaser, 32, 32);
        break;
    case GITS_CREADR:
        *data = extract64(s->creadr, 0, 32);
        break;
    case GITS_CREADR + 4:
        *data = extract64(s->creadr, 32, 32);
        break;
    case GITS_CWRITER:
        *data = extract64(s->cwriter, 0, 32);
        break;
    case GITS_CWRITER + 4:
        *data = extract64(s->cwriter, 32, 32);
        break;
    case GITS_BASER ... GITS_BASER + 0x3f:
        index = (offset - GITS_BASER) / 8;
        if (offset & 7) {
            *data = extract64(s->baser[index], 32, 32);
        } else {
            *data = extract64(s->baser[index], 0, 32);
        }
        break;
    default:
        result = false;
        break;
    }
    return result;
}

static bool its_writell(GICv3ITSState *s, hwaddr offset,
                               uint64_t value, MemTxAttrs attrs)
{
    bool result = true;
    int index;

    switch (offset) {
    case GITS_BASER ... GITS_BASER + 0x3f:
        /*
         * IMPDEF choice:- GITS_BASERn register becomes RO if ITS is
         *                 already enabled
         */
        if (!(s->ctlr & R_GITS_CTLR_ENABLED_MASK)) {
            index = (offset - GITS_BASER) / 8;
            if (s->baser[index] == 0) {
                /* Unimplemented GITS_BASERn: RAZ/WI */
                break;
            }
            s->baser[index] &= GITS_BASER_RO_MASK;
            s->baser[index] |= (value & ~GITS_BASER_RO_MASK);
        }
        break;
    case GITS_CBASER:
        /*
         * IMPDEF choice:- GITS_CBASER register becomes RO if ITS is
         *                 already enabled
         */
        if (!(s->ctlr & R_GITS_CTLR_ENABLED_MASK)) {
            s->cbaser = value;
            s->creadr = 0;
        }
        break;
    case GITS_CWRITER:
        s->cwriter = value & ~R_GITS_CWRITER_RETRY_MASK;
        if (s->cwriter != s->creadr) {
            process_cmdq(s);
        }
        break;
    case GITS_CREADR:
        if (s->gicv3->gicd_ctlr & GICD_CTLR_DS) {
            s->creadr = value & ~R_GITS_CREADR_STALLED_MASK;
        } else {
            /* RO register, ignore the write */
            qemu_log_mask(LOG_GUEST_ERROR,
                          "%s: invalid guest write to RO register at offset "
                          TARGET_FMT_plx "\n", __func__, offset);
        }
        break;
    case GITS_TYPER:
        /* RO registers, ignore the write */
        qemu_log_mask(LOG_GUEST_ERROR,
                      "%s: invalid guest write to RO register at offset "
                      TARGET_FMT_plx "\n", __func__, offset);
        break;
    default:
        result = false;
        break;
    }
    return result;
}

static bool its_readll(GICv3ITSState *s, hwaddr offset,
                              uint64_t *data, MemTxAttrs attrs)
{
    bool result = true;
    int index;

    switch (offset) {
    case GITS_TYPER:
        *data = s->typer;
        break;
    case GITS_BASER ... GITS_BASER + 0x3f:
        index = (offset - GITS_BASER) / 8;
        *data = s->baser[index];
        break;
    case GITS_CBASER:
        *data = s->cbaser;
        break;
    case GITS_CREADR:
        *data = s->creadr;
        break;
    case GITS_CWRITER:
        *data = s->cwriter;
        break;
    default:
        result = false;
        break;
    }
    return result;
}

static MemTxResult gicv3_its_read(void *opaque, hwaddr offset, uint64_t *data,
                                  unsigned size, MemTxAttrs attrs)
{
    GICv3ITSState *s = (GICv3ITSState *)opaque;
    bool result;

    switch (size) {
    case 4:
        result = its_readl(s, offset, data, attrs);
        break;
    case 8:
        result = its_readll(s, offset, data, attrs);
        break;
    default:
        result = false;
        break;
    }

    if (!result) {
        qemu_log_mask(LOG_GUEST_ERROR,
                      "%s: invalid guest read at offset " TARGET_FMT_plx
                      " size %u\n", __func__, offset, size);
        trace_gicv3_its_badread(offset, size);
        /*
         * The spec requires that reserved registers are RAZ/WI;
         * so use false returns from leaf functions as a way to
         * trigger the guest-error logging but don't return it to
         * the caller, or we'll cause a spurious guest data abort.
         */
        *data = 0;
    } else {
        trace_gicv3_its_read(offset, *data, size);
    }
    return MEMTX_OK;
}

static MemTxResult gicv3_its_write(void *opaque, hwaddr offset, uint64_t data,
                                   unsigned size, MemTxAttrs attrs)
{
    GICv3ITSState *s = (GICv3ITSState *)opaque;
    bool result;

    switch (size) {
    case 4:
        result = its_writel(s, offset, data, attrs);
        break;
    case 8:
        result = its_writell(s, offset, data, attrs);
        break;
    default:
        result = false;
        break;
    }

    if (!result) {
        qemu_log_mask(LOG_GUEST_ERROR,
                      "%s: invalid guest write at offset " TARGET_FMT_plx
                      " size %u\n", __func__, offset, size);
        trace_gicv3_its_badwrite(offset, data, size);
        /*
         * The spec requires that reserved registers are RAZ/WI;
         * so use false returns from leaf functions as a way to
         * trigger the guest-error logging but don't return it to
         * the caller, or we'll cause a spurious guest data abort.
         */
    } else {
        trace_gicv3_its_write(offset, data, size);
    }
    return MEMTX_OK;
}

static const MemoryRegionOps gicv3_its_control_ops = {
    .read_with_attrs = gicv3_its_read,
    .write_with_attrs = gicv3_its_write,
    .valid.min_access_size = 4,
    .valid.max_access_size = 8,
    .impl.min_access_size = 4,
    .impl.max_access_size = 8,
    .endianness = DEVICE_NATIVE_ENDIAN,
};

static const MemoryRegionOps gicv3_its_translation_ops = {
    .read_with_attrs = gicv3_its_translation_read,
    .write_with_attrs = gicv3_its_translation_write,
    .valid.min_access_size = 2,
    .valid.max_access_size = 4,
    .impl.min_access_size = 2,
    .impl.max_access_size = 4,
    .endianness = DEVICE_NATIVE_ENDIAN,
};

static void gicv3_arm_its_realize(DeviceState *dev, Error **errp)
{
    GICv3ITSState *s = ARM_GICV3_ITS_COMMON(dev);
    int i;

    for (i = 0; i < s->gicv3->num_cpu; i++) {
        if (!(s->gicv3->cpu[i].gicr_typer & GICR_TYPER_PLPIS)) {
            error_setg(errp, "Physical LPI not supported by CPU %d", i);
            return;
        }
    }

    gicv3_add_its(s->gicv3, dev);

    gicv3_its_init_mmio(s, &gicv3_its_control_ops, &gicv3_its_translation_ops);

    /* set the ITS default features supported */
    s->typer = FIELD_DP64(s->typer, GITS_TYPER, PHYSICAL, 1);
    s->typer = FIELD_DP64(s->typer, GITS_TYPER, ITT_ENTRY_SIZE,
                          ITS_ITT_ENTRY_SIZE - 1);
    s->typer = FIELD_DP64(s->typer, GITS_TYPER, IDBITS, ITS_IDBITS);
    s->typer = FIELD_DP64(s->typer, GITS_TYPER, DEVBITS, ITS_DEVBITS);
    s->typer = FIELD_DP64(s->typer, GITS_TYPER, CIL, 1);
    s->typer = FIELD_DP64(s->typer, GITS_TYPER, CIDBITS, ITS_CIDBITS);
}

static void gicv3_its_reset(DeviceState *dev)
{
    GICv3ITSState *s = ARM_GICV3_ITS_COMMON(dev);
    GICv3ITSClass *c = ARM_GICV3_ITS_GET_CLASS(s);

    c->parent_reset(dev);

    /* Quiescent bit reset to 1 */
    s->ctlr = FIELD_DP32(s->ctlr, GITS_CTLR, QUIESCENT, 1);

    /*
     * setting GITS_BASER0.Type = 0b001 (Device)
     *         GITS_BASER1.Type = 0b100 (Collection Table)
     *         GITS_BASER2.Type = 0b010 (vPE) for GICv4 and later
     *         GITS_BASER<n>.Type,where n = 3 to 7 are 0b00 (Unimplemented)
     *         GITS_BASER<0,1>.Page_Size = 64KB
     * and default translation table entry size to 16 bytes
     */
    s->baser[0] = FIELD_DP64(s->baser[0], GITS_BASER, TYPE,
                             GITS_BASER_TYPE_DEVICE);
    s->baser[0] = FIELD_DP64(s->baser[0], GITS_BASER, PAGESIZE,
                             GITS_BASER_PAGESIZE_64K);
    s->baser[0] = FIELD_DP64(s->baser[0], GITS_BASER, ENTRYSIZE,
                             GITS_DTE_SIZE - 1);

    s->baser[1] = FIELD_DP64(s->baser[1], GITS_BASER, TYPE,
                             GITS_BASER_TYPE_COLLECTION);
    s->baser[1] = FIELD_DP64(s->baser[1], GITS_BASER, PAGESIZE,
                             GITS_BASER_PAGESIZE_64K);
    s->baser[1] = FIELD_DP64(s->baser[1], GITS_BASER, ENTRYSIZE,
                             GITS_CTE_SIZE - 1);

    if (its_feature_virtual(s)) {
        s->baser[2] = FIELD_DP64(s->baser[2], GITS_BASER, TYPE,
                                 GITS_BASER_TYPE_VPE);
        s->baser[2] = FIELD_DP64(s->baser[2], GITS_BASER, PAGESIZE,
                                 GITS_BASER_PAGESIZE_64K);
        s->baser[2] = FIELD_DP64(s->baser[2], GITS_BASER, ENTRYSIZE,
                                 GITS_VPE_SIZE - 1);
    }
}

static void gicv3_its_post_load(GICv3ITSState *s)
{
    if (s->ctlr & R_GITS_CTLR_ENABLED_MASK) {
        extract_table_params(s);
        extract_cmdq_params(s);
    }
}

static Property gicv3_its_props[] = {
    DEFINE_PROP_LINK("parent-gicv3", GICv3ITSState, gicv3, "arm-gicv3",
                     GICv3State *),
    DEFINE_PROP_END_OF_LIST(),
};

static void gicv3_its_class_init(ObjectClass *klass, void *data)
{
    DeviceClass *dc = DEVICE_CLASS(klass);
    GICv3ITSClass *ic = ARM_GICV3_ITS_CLASS(klass);
    GICv3ITSCommonClass *icc = ARM_GICV3_ITS_COMMON_CLASS(klass);

    dc->realize = gicv3_arm_its_realize;
    device_class_set_props(dc, gicv3_its_props);
    device_class_set_parent_reset(dc, gicv3_its_reset, &ic->parent_reset);
    icc->post_load = gicv3_its_post_load;
}

static const TypeInfo gicv3_its_info = {
    .name = TYPE_ARM_GICV3_ITS,
    .parent = TYPE_ARM_GICV3_ITS_COMMON,
    .instance_size = sizeof(GICv3ITSState),
    .class_init = gicv3_its_class_init,
    .class_size = sizeof(GICv3ITSClass),
};

static void gicv3_its_register_types(void)
{
    type_register_static(&gicv3_its_info);
}

type_init(gicv3_its_register_types)