/* $NetBSD: qcomscm.c,v 1.1 2024/12/30 12:31:10 jmcneill Exp $ */
/* $OpenBSD: qcscm.c,v 1.9 2024/08/04 15:30:08 kettenis Exp $ */
/*
 * Copyright (c) 2022 Patrick Wildt <patrick@blueri.se>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/device.h>
#include <sys/kmem.h>
#include <sys/bus.h>
#include <sys/uuid.h>

#include <dev/efi/efi.h>
#include <dev/acpi/acpivar.h>
#include <dev/acpi/qcomscm.h>

#define ARM_SMCCC_STD_CALL                      (0U << 31)
#define ARM_SMCCC_FAST_CALL                     (1U << 31)
#define ARM_SMCCC_LP64                          (1U << 30)
#define ARM_SMCCC_OWNER_SIP                     2

#define QCTEE_TZ_OWNER_TZ_APPS                  48
#define QCTEE_TZ_OWNER_QSEE_OS                  50

#define QCTEE_TZ_SVC_APP_ID_PLACEHOLDER         0
#define QCTEE_TZ_SVC_APP_MGR                    1

#define QCTEE_OS_RESULT_SUCCESS                 0
#define QCTEE_OS_RESULT_INCOMPLETE              1
#define QCTEE_OS_RESULT_BLOCKED_ON_LISTENER     2
#define QCTEE_OS_RESULT_FAILURE                 0xffffffff

#define QCTEE_OS_SCM_RES_APP_ID                 0xee01
#define QCTEE_OS_SCM_RES_QSEOS_LISTENER_ID      0xee02

#define QCTEE_UEFI_GET_VARIABLE                 0x8000
#define QCTEE_UEFI_SET_VARIABLE                 0x8001
#define QCTEE_UEFI_GET_NEXT_VARIABLE            0x8002
#define QCTEE_UEFI_QUERY_VARIABLE_INFO          0x8003

#define QCTEE_UEFI_SUCCESS                      0
#define QCTEE_UEFI_BUFFER_TOO_SMALL             0x80000005
#define QCTEE_UEFI_DEVICE_ERROR                 0x80000007
#define QCTEE_UEFI_NOT_FOUND                    0x8000000e

#define QCSCM_SVC_PIL                   0x02
#define QCSCM_PIL_PAS_INIT_IMAGE        0x01
#define QCSCM_PIL_PAS_MEM_SETUP         0x02
#define QCSCM_PIL_PAS_AUTH_AND_RESET    0x05
#define QCSCM_PIL_PAS_SHUTDOWN          0x06
#define QCSCM_PIL_PAS_IS_SUPPORTED      0x07
#define QCSCM_PIL_PAS_MSS_RESET         0x0a

#define QCSCM_INTERRUPTED               1
#define QCSCM_EBUSY                     -22

#define QCSCM_ARGINFO_NUM(x)            (((x) & 0xf) << 0)
#define QCSCM_ARGINFO_TYPE(x, y)        (((y) & 0x3) << (4 + 2 * (x)))
#define QCSCM_ARGINFO_TYPE_VAL          0
#define QCSCM_ARGINFO_TYPE_RO           1
#define QCSCM_ARGINFO_TYPE_RW           2
#define QCSCM_ARGINFO_TYPE_BUFVAL       3

#define EFI_VARIABLE_NON_VOLATILE       0x00000001
#define EFI_VARIABLE_BOOTSERVICE_ACCESS 0x00000002
#define EFI_VARIABLE_RUNTIME_ACCESS     0x00000004

#define UNIX_GPS_EPOCH_OFFSET           315964800

#define EFI_VAR_RTCINFO                 __UNCONST(u"RTCInfo")

extern struct arm32_bus_dma_tag arm_generic_dma_tag;

struct qcscm_dmamem {
        bus_dmamap_t            qdm_map;
        bus_dma_segment_t       qdm_seg;
        size_t                  qdm_size;
        void                    *qdm_kva;
};

#define QCSCM_DMA_MAP(_qdm)             ((_qdm)->qdm_map)
#define QCSCM_DMA_LEN(_qdm)             ((_qdm)->qdm_size)
#define QCSCM_DMA_DVA(_qdm)             ((uint64_t)(_qdm)->qdm_map->dm_segs[0].ds_addr)
#define QCSCM_DMA_KVA(_qdm, off)        ((void *)((uintptr_t)(_qdm)->qdm_kva + (off)))

static struct uuid qcscm_uefi_rtcinfo_guid =
  { 0x882f8c2b, 0x9646, 0x435f,
    0x8d, 0xe5, { 0xf2, 0x08, 0xff, 0x80, 0xc1, 0xbd } };

struct qcscm_softc {
        device_t                sc_dev;
        bus_dma_tag_t           sc_dmat;

        struct qcscm_dmamem     *sc_extarg;
        uint32_t                sc_uefi_id;
};

static int      qcscm_match(device_t, cfdata_t, void *);
static void     qcscm_attach(device_t, device_t, void *);

CFATTACH_DECL_NEW(qcomscm, sizeof(struct qcscm_softc),
    qcscm_match, qcscm_attach, NULL, NULL);

static inline void      qcscm_smc_exec(uint64_t *, uint64_t *);
int     qcscm_smc_call(struct qcscm_softc *, uint8_t, uint8_t, uint8_t,
            uint32_t, uint64_t *, int, uint64_t *);
int     qcscm_tee_app_get_id(struct qcscm_softc *, const char *, uint32_t *);
int     qcscm_tee_app_send(struct qcscm_softc *, uint32_t, uint64_t, uint64_t,
            uint64_t, uint64_t);

efi_status qcscm_uefi_get_variable(struct qcscm_softc *, efi_char *,
            int, struct uuid *, uint32_t *, uint8_t *, int *);
efi_status qcscm_uefi_set_variable(struct qcscm_softc *, efi_char *,
            int, struct uuid *, uint32_t, uint8_t *, int);
efi_status qcscm_uefi_get_next_variable(struct qcscm_softc *,
            efi_char *, int *, struct uuid *);

efi_status qcscm_efi_get_variable(efi_char *, struct uuid *, uint32_t *,
            u_long *, void *);
efi_status qcscm_efi_set_variable(efi_char *, struct uuid *, uint32_t,
            u_long, void *);
efi_status qcscm_efi_get_next_variable_name(u_long *, efi_char *, struct uuid *);

#ifdef QCSCM_DEBUG
void    qcscm_uefi_dump_variables(struct qcscm_softc *);
void    qcscm_uefi_dump_variable(struct qcscm_softc *, efi_char *, int,
            struct uuid *);
#endif

int     qcscm_uefi_rtc_get(uint32_t *);
int     qcscm_uefi_rtc_set(uint32_t);

struct qcscm_dmamem *
         qcscm_dmamem_alloc(struct qcscm_softc *, bus_size_t, bus_size_t);
void     qcscm_dmamem_free(struct qcscm_softc *, struct qcscm_dmamem *);

struct qcscm_softc *qcscm_sc;

static const struct device_compatible_entry compat_data[] = {
        { .compat = "QCOM04DD" },
        DEVICE_COMPAT_EOL
};

static int
qcscm_match(device_t parent, cfdata_t cf, void *aux)
{
        struct acpi_attach_args *aa = aux;

        return acpi_compatible_match(aa, compat_data);
}

static void
qcscm_attach(device_t parent, device_t self, void *aux)
{
        struct qcscm_softc *sc = device_private(self);
        int error;

        sc->sc_dev = self;
        error = bus_dmatag_subregion(&arm_generic_dma_tag,
            0, __MASK(32), &sc->sc_dmat, 0);
        KASSERT(error == 0);

        sc->sc_extarg = qcscm_dmamem_alloc(sc, PAGE_SIZE, 8);
        if (sc->sc_extarg == NULL) {
                aprint_error(": can't allocate memory for extended args\n");
                return;
        }

        aprint_naive("\n");
        aprint_normal("\n");

#if notyet
        error = qcscm_tee_app_get_id(sc, "qcom.tz.uefisecapp", &sc->sc_uefi_id);
        if (error != 0) {
                aprint_error_dev(self, "can't retrieve UEFI App: %d\n", error);
                sc->sc_uefi_id = UINT32_MAX;
        }
#else
        sc->sc_uefi_id = UINT32_MAX;
#endif

        qcscm_sc = sc;

#ifdef QCSCM_DEBUG
        qcscm_uefi_dump_variables(sc);
        qcscm_uefi_dump_variable(sc, EFI_VAR_RTCINFO, sizeof(EFI_VAR_RTCINFO),
            &qcscm_uefi_rtcinfo_guid);
#endif
}

/* Expects an uint64_t[18] */
static inline void
qcscm_smc_exec(uint64_t *in, uint64_t *out)
{
        asm volatile(
            "ldp x0, x1, [%[in], #0]\n"
            "ldp x2, x3, [%[in], #16]\n"
            "ldp x4, x5, [%[in], #32]\n"
            "ldp x6, x7, [%[in], #48]\n"
            "ldp x8, x9, [%[in], #64]\n"
            "ldp x10, x11, [%[in], #80]\n"
            "ldp x12, x13, [%[in], #96]\n"
            "ldp x14, x15, [%[in], #112]\n"
            "ldp x16, x17, [%[in], #128]\n"
            "smc #0\n"
            "stp x0, x1, [%[out], #0]\n"
            "stp x2, x3, [%[out], #16]\n"
            "stp x4, x5, [%[out], #32]\n"
            "stp x6, x7, [%[out], #48]\n"
            "stp x8, x9, [%[out], #64]\n"
            "stp x10, x11, [%[out], #80]\n"
            "stp x12, x13, [%[out], #96]\n"
            "stp x14, x15, [%[out], #112]\n"
            "stp x16, x17, [%[out], #128]\n"
            :
            : [in] "r" (in), [out] "r" (out)
            : "x0", "x1", "x2", "x3", "x4", "x5",
              "x6", "x7", "x8", "x9", "x10", "x11",
              "x12", "x13", "x14", "x15", "x16", "x17",
              "memory");
}

int
qcscm_smc_call(struct qcscm_softc *sc, uint8_t owner, uint8_t svc, uint8_t cmd,
    uint32_t arginfo, uint64_t *args, int arglen, uint64_t *res)
{
        uint64_t smcreq[18] = { 0 }, smcres[18] = { 0 };
        uint64_t *smcextreq;
        int i, busy_retry;

        /* 4 of our 10 possible args fit into x2-x5 */
        smcreq[0] = ARM_SMCCC_STD_CALL | ARM_SMCCC_LP64 |
            owner << 24 | svc << 8 | cmd;
#ifdef QCSCM_DEBUG_SMC
        device_printf(sc->sc_dev, "owner %#x svc %#x cmd %#x req %#lx\n",
            owner, svc, cmd, smcreq[0]);
#endif
        smcreq[1] = arginfo;
        for (i = 0; i < uimin(arglen, 4); i++)
                smcreq[2 + i] = args[i];

        /* In case we have more than 4, use x5 as ptr to extra args */
        if (arglen > 4) {
                smcreq[5] = QCSCM_DMA_DVA(sc->sc_extarg);
                smcextreq = QCSCM_DMA_KVA(sc->sc_extarg, 0);
                for (i = 0; i < uimin(arglen - 3, 7); i++) {
                        smcextreq[i] = args[3 + i];
                }
                cpu_drain_writebuf();
        }

#ifdef QCSCM_DEBUG_SMC
        device_printf(sc->sc_dev, "smcreq[before]:");
        for (i = 0; i < __arraycount(smcreq); i++) {
                printf(" %#lx", smcreq[i]);
        }
        printf("\n");
#endif
        for (busy_retry = 20; busy_retry > 0; busy_retry--) {
                int intr_retry = 1000000;
                for (;;) {
                        qcscm_smc_exec(smcreq, smcres);
                        /* If the call gets interrupted, try again and re-pass x0/x6 */
                        if (smcres[0] == QCSCM_INTERRUPTED) {
                                if (--intr_retry == 0) {
                                        break;
                                }
                                smcreq[0] = smcres[0];
                                smcreq[6] = smcres[6];
                                continue;
                        }
                        break;
                }

                if (smcres[0] != QCSCM_EBUSY) {
                        break;
                }
                delay(30000);
        }

#ifdef QCSCM_DEBUG_SMC
        device_printf(sc->sc_dev, "smcreq[after]:");
        for (i = 0; i < __arraycount(smcreq); i++) {
                printf(" %#lx", smcreq[i]);
        }
        printf("\n");
        device_printf(sc->sc_dev, "smcres[after]:");
        for (i = 0; i < __arraycount(smcres); i++) {
                printf(" %#lx", smcres[i]);
        }
        printf("\n");
#endif

        if (res) {
                res[0] = smcres[1];
                res[1] = smcres[2];
                res[2] = smcres[3];
        }

        return smcres[0];
}

/* Retrieve id of app running in TEE by name */
int
qcscm_tee_app_get_id(struct qcscm_softc *sc, const char *name, uint32_t *id)
{
        struct qcscm_dmamem *qdm;
        uint64_t res[3];
        uint64_t args[2];
        uint32_t arginfo;
        int ret;

        /* Max name length is 64 */
        if (strlen(name) > 64)
                return EINVAL;

        /* Alloc some phys mem to hold the name */
        qdm = qcscm_dmamem_alloc(sc, PAGE_SIZE, 8);
        if (qdm == NULL)
                return ENOMEM;

        /* Copy name of app we want to get an id for to page */
        memcpy(QCSCM_DMA_KVA(qdm, 0), name, strlen(name));

        /* Pass address of name and length */
        arginfo = QCSCM_ARGINFO_NUM(__arraycount(args));
        arginfo |= QCSCM_ARGINFO_TYPE(0, QCSCM_ARGINFO_TYPE_RW);
        arginfo |= QCSCM_ARGINFO_TYPE(1, QCSCM_ARGINFO_TYPE_VAL);
        args[0] = QCSCM_DMA_DVA(qdm);
        args[1] = strlen(name);

        cpu_drain_writebuf();

        /* Make call into TEE */
        ret = qcscm_smc_call(sc, QCTEE_TZ_OWNER_QSEE_OS, QCTEE_TZ_SVC_APP_MGR,
            0x03, arginfo, args, __arraycount(args), res);

        /* If the call succeeded, check the response status */
        if (ret == 0)
                ret = res[0];

        /* If the response status is successful as well, retrieve data */
        if (ret == 0)
                *id = res[2];

        qcscm_dmamem_free(sc, qdm);
        return ret;
}

/* Message interface to app running in TEE */
int
qcscm_tee_app_send(struct qcscm_softc *sc, uint32_t id, uint64_t req_phys,
    uint64_t req_len, uint64_t rsp_phys, uint64_t rsp_len)
{
        uint64_t res[3];
        uint64_t args[5];
        uint32_t arginfo;
        int ret;

        /* Pass id of app we target, plus request and response buffers */
        arginfo = QCSCM_ARGINFO_NUM(__arraycount(args));
        arginfo |= QCSCM_ARGINFO_TYPE(0, QCSCM_ARGINFO_TYPE_VAL);
        arginfo |= QCSCM_ARGINFO_TYPE(1, QCSCM_ARGINFO_TYPE_RW);
        arginfo |= QCSCM_ARGINFO_TYPE(2, QCSCM_ARGINFO_TYPE_VAL);
        arginfo |= QCSCM_ARGINFO_TYPE(3, QCSCM_ARGINFO_TYPE_RW);
        arginfo |= QCSCM_ARGINFO_TYPE(4, QCSCM_ARGINFO_TYPE_VAL);
        args[0] = id;
        args[1] = req_phys;
        args[2] = req_len;
        args[3] = rsp_phys;
        args[4] = rsp_len;

        /* Make call into TEE */
        ret = qcscm_smc_call(sc, QCTEE_TZ_OWNER_TZ_APPS,
            QCTEE_TZ_SVC_APP_ID_PLACEHOLDER, 0x01,
            arginfo, args, __arraycount(args), res);

        /* If the call succeeded, check the response status */
        if (ret == 0)
                ret = res[0];

        return ret;
}

struct qcscm_req_uefi_get_variable {
        uint32_t command_id;
        uint32_t length;
        uint32_t name_offset;
        uint32_t name_size;
        uint32_t guid_offset;
        uint32_t guid_size;
        uint32_t data_size;
};

struct qcscm_rsp_uefi_get_variable {
        uint32_t command_id;
        uint32_t length;
        uint32_t status;
        uint32_t attributes;
        uint32_t data_offset;
        uint32_t data_size;
};

efi_status
qcscm_uefi_get_variable(struct qcscm_softc *sc,
    efi_char *name, int name_size, struct uuid *guid,
    uint32_t *attributes, uint8_t *data, int *data_size)
{
        struct qcscm_req_uefi_get_variable *req;
        struct qcscm_rsp_uefi_get_variable *resp;
        struct qcscm_dmamem *qdm;
        size_t reqsize, respsize;
        off_t reqoff, respoff;
        int ret;

        if (sc->sc_uefi_id == UINT32_MAX)
                return QCTEE_UEFI_DEVICE_ERROR;

        reqsize = ALIGN(sizeof(*req)) + ALIGN(name_size) + ALIGN(sizeof(*guid));
        respsize = ALIGN(sizeof(*resp)) + ALIGN(*data_size);

        reqoff = 0;
        respoff = reqsize;

        qdm = qcscm_dmamem_alloc(sc, round_page(reqsize + respsize), 8);
        if (qdm == NULL)
                return QCTEE_UEFI_DEVICE_ERROR;

        req = QCSCM_DMA_KVA(qdm, reqoff);
        req->command_id = QCTEE_UEFI_GET_VARIABLE;
        req->data_size = *data_size;
        req->name_offset = ALIGN(sizeof(*req));
        req->name_size = name_size;
        req->guid_offset = ALIGN(req->name_offset + req->name_size);
        req->guid_size = sizeof(*guid);
        req->length = req->guid_offset + req->guid_size;

        memcpy((char *)req + req->guid_offset, guid, sizeof(*guid));
        memcpy((char *)req + req->name_offset, name, name_size);

        cpu_drain_writebuf();

        ret = qcscm_tee_app_send(sc, sc->sc_uefi_id,
            QCSCM_DMA_DVA(qdm) + reqoff, reqsize,
            QCSCM_DMA_DVA(qdm) + respoff, respsize);
        if (ret) {
                qcscm_dmamem_free(sc, qdm);
                return QCTEE_UEFI_DEVICE_ERROR;
        }

        cpu_drain_writebuf();

        resp = QCSCM_DMA_KVA(qdm, respoff);
        if (resp->command_id != QCTEE_UEFI_GET_VARIABLE ||
            resp->length < sizeof(*resp)) {
                qcscm_dmamem_free(sc, qdm);
                return QCTEE_UEFI_DEVICE_ERROR;
        }

        if (resp->status) {
                if (resp->status == QCTEE_UEFI_BUFFER_TOO_SMALL)
                        *data_size = resp->data_size;
                if (attributes)
                        *attributes = resp->attributes;
                ret = resp->status;
                qcscm_dmamem_free(sc, qdm);
                return ret;
        }

        if (resp->length > respsize ||
            resp->data_offset + resp->data_size > resp->length) {
                qcscm_dmamem_free(sc, qdm);
                return QCTEE_UEFI_DEVICE_ERROR;
        }

        if (attributes)
                *attributes = resp->attributes;

        if (*data_size == 0) {
                *data_size = resp->data_size;
                qcscm_dmamem_free(sc, qdm);
                return QCTEE_UEFI_SUCCESS;
        }

        if (resp->data_size > *data_size) {
                *data_size = resp->data_size;
                qcscm_dmamem_free(sc, qdm);
                return QCTEE_UEFI_BUFFER_TOO_SMALL;
        }

        memcpy(data, (char *)resp + resp->data_offset, resp->data_size);
        *data_size = resp->data_size;

        qcscm_dmamem_free(sc, qdm);
        return EFI_SUCCESS;
}

struct qcscm_req_uefi_set_variable {
        uint32_t command_id;
        uint32_t length;
        uint32_t name_offset;
        uint32_t name_size;
        uint32_t guid_offset;
        uint32_t guid_size;
        uint32_t attributes;
        uint32_t data_offset;
        uint32_t data_size;
};

struct qcscm_rsp_uefi_set_variable {
        uint32_t command_id;
        uint32_t length;
        uint32_t status;
        uint32_t unknown[2];
};

efi_status
qcscm_uefi_set_variable(struct qcscm_softc *sc,
    efi_char *name, int name_size, struct uuid *guid,
    uint32_t attributes, uint8_t *data, int data_size)
{
        struct qcscm_req_uefi_set_variable *req;
        struct qcscm_rsp_uefi_set_variable *resp;
        struct qcscm_dmamem *qdm;
        size_t reqsize, respsize;
        off_t reqoff, respoff;
        int ret;

        if (sc->sc_uefi_id == UINT32_MAX)
                return QCTEE_UEFI_DEVICE_ERROR;

        reqsize = ALIGN(sizeof(*req)) + ALIGN(name_size) + ALIGN(sizeof(*guid)) +
            ALIGN(data_size);
        respsize = ALIGN(sizeof(*resp));

        reqoff = 0;
        respoff = reqsize;

        qdm = qcscm_dmamem_alloc(sc, round_page(reqsize + respsize), 8);
        if (qdm == NULL)
                return QCTEE_UEFI_DEVICE_ERROR;

        req = QCSCM_DMA_KVA(qdm, reqoff);
        req->command_id = QCTEE_UEFI_SET_VARIABLE;
        req->attributes = attributes;
        req->name_offset = ALIGN(sizeof(*req));
        req->name_size = name_size;
        req->guid_offset = ALIGN(req->name_offset + req->name_size);
        req->guid_size = sizeof(*guid);
        req->data_offset = ALIGN(req->guid_offset + req->guid_size);
        req->data_size = data_size;
        req->length = req->data_offset + req->data_size;

        memcpy((char *)req + req->name_offset, name, name_size);
        memcpy((char *)req + req->guid_offset, guid, sizeof(*guid));
        memcpy((char *)req + req->data_offset, data, data_size);

        ret = qcscm_tee_app_send(sc, sc->sc_uefi_id,
            QCSCM_DMA_DVA(qdm) + reqoff, reqsize,
            QCSCM_DMA_DVA(qdm) + respoff, respsize);
        if (ret) {
                qcscm_dmamem_free(sc, qdm);
                return QCTEE_UEFI_DEVICE_ERROR;
        }

        resp = QCSCM_DMA_KVA(qdm, respoff);
        if (resp->command_id != QCTEE_UEFI_SET_VARIABLE ||
            resp->length < sizeof(*resp) || resp->length > respsize) {
                qcscm_dmamem_free(sc, qdm);
                return QCTEE_UEFI_DEVICE_ERROR;
        }

        if (resp->status) {
                ret = resp->status;
                qcscm_dmamem_free(sc, qdm);
                return ret;
        }

        qcscm_dmamem_free(sc, qdm);
        return QCTEE_UEFI_SUCCESS;
}

struct qcscm_req_uefi_get_next_variable {
        uint32_t command_id;
        uint32_t length;
        uint32_t guid_offset;
        uint32_t guid_size;
        uint32_t name_offset;
        uint32_t name_size;
};

struct qcscm_rsp_uefi_get_next_variable {
        uint32_t command_id;
        uint32_t length;
        uint32_t status;
        uint32_t guid_offset;
        uint32_t guid_size;
        uint32_t name_offset;
        uint32_t name_size;
};

efi_status
qcscm_uefi_get_next_variable(struct qcscm_softc *sc,
    efi_char *name, int *name_size, struct uuid *guid)
{
        struct qcscm_req_uefi_get_next_variable *req;
        struct qcscm_rsp_uefi_get_next_variable *resp;
        struct qcscm_dmamem *qdm;
        size_t reqsize, respsize;
        off_t reqoff, respoff;
        int ret;

        if (sc->sc_uefi_id == UINT32_MAX)
                return QCTEE_UEFI_DEVICE_ERROR;

        reqsize = ALIGN(sizeof(*req)) + ALIGN(sizeof(*guid)) + ALIGN(*name_size);
        respsize = ALIGN(sizeof(*resp)) + ALIGN(sizeof(*guid)) + ALIGN(*name_size);

        reqoff = 0;
        respoff = reqsize;

        qdm = qcscm_dmamem_alloc(sc, round_page(reqsize + respsize), 8);
        if (qdm == NULL)
                return QCTEE_UEFI_DEVICE_ERROR;

        req = QCSCM_DMA_KVA(qdm, reqoff);
        req->command_id = QCTEE_UEFI_GET_NEXT_VARIABLE;
        req->guid_offset = ALIGN(sizeof(*req));
        req->guid_size = sizeof(*guid);
        req->name_offset = ALIGN(req->guid_offset + req->guid_size);
        req->name_size = *name_size;
        req->length = req->name_offset + req->name_size;

        memcpy((char *)req + req->guid_offset, guid, sizeof(*guid));
        memcpy((char *)req + req->name_offset, name, *name_size);

        ret = qcscm_tee_app_send(sc, sc->sc_uefi_id,
            QCSCM_DMA_DVA(qdm) + reqoff, reqsize,
            QCSCM_DMA_DVA(qdm) + respoff, respsize);
        if (ret) {
                qcscm_dmamem_free(sc, qdm);
                return QCTEE_UEFI_DEVICE_ERROR;
        }

        resp = QCSCM_DMA_KVA(qdm, respoff);
        if (resp->command_id != QCTEE_UEFI_GET_NEXT_VARIABLE ||
            resp->length < sizeof(*resp) || resp->length > respsize) {
                qcscm_dmamem_free(sc, qdm);
                return QCTEE_UEFI_DEVICE_ERROR;
        }

        if (resp->status) {
                if (resp->status == QCTEE_UEFI_BUFFER_TOO_SMALL)
                        *name_size = resp->name_size;
                ret = resp->status;
                qcscm_dmamem_free(sc, qdm);
                return ret;
        }

        if (resp->guid_offset + resp->guid_size > resp->length ||
            resp->name_offset + resp->name_size > resp->length) {
                qcscm_dmamem_free(sc, qdm);
                return QCTEE_UEFI_DEVICE_ERROR;
        }

        if (resp->guid_size != sizeof(*guid)) {
                qcscm_dmamem_free(sc, qdm);
                return QCTEE_UEFI_DEVICE_ERROR;
        }

        if (resp->name_size > *name_size) {
                *name_size = resp->name_size;
                qcscm_dmamem_free(sc, qdm);
                return QCTEE_UEFI_BUFFER_TOO_SMALL;
        }

        memcpy(guid, (char *)resp + resp->guid_offset, sizeof(*guid));
        memcpy(name, (char *)resp + resp->name_offset, resp->name_size);
        *name_size = resp->name_size;

        qcscm_dmamem_free(sc, qdm);
        return QCTEE_UEFI_SUCCESS;
}

efi_status
qcscm_efi_get_variable(efi_char *name, struct uuid *guid, uint32_t *attributes,
   u_long *data_size, void *data)
{
        struct qcscm_softc *sc = qcscm_sc;
        efi_status status;
        int name_size;
        int size;

        name_size = 0;
        while (name[name_size])
                name_size++;
        name_size++;

        size = *data_size;
        status = qcscm_uefi_get_variable(sc, name, name_size * 2, guid,
            attributes, data, &size);
        *data_size = size;

        /* Convert 32-bit status code to 64-bit. */
        return ((status & 0xf0000000) << 32 | (status & 0x0fffffff));
}

efi_status
qcscm_efi_set_variable(efi_char *name, struct uuid *guid, uint32_t attributes,
    u_long data_size, void *data)
{
        struct qcscm_softc *sc = qcscm_sc;
        efi_status status;
        int name_size;

        name_size = 0;
        while (name[name_size])
                name_size++;
        name_size++;

        status = qcscm_uefi_set_variable(sc, name, name_size * 2, guid,
            attributes, data, data_size);

        /* Convert 32-bit status code to 64-bit. */
        return ((status & 0xf0000000) << 32 | (status & 0x0fffffff));
}

efi_status
qcscm_efi_get_next_variable_name(u_long *name_size, efi_char *name,
    struct uuid *guid)
{
        struct qcscm_softc *sc = qcscm_sc;
        efi_status status;
        int size;

        size = *name_size;
        status = qcscm_uefi_get_next_variable(sc, name, &size, guid);
        *name_size = size;

        /* Convert 32-bit status code to 64-bit. */
        return ((status & 0xf0000000) << 32 | (status & 0x0fffffff));
}

#ifdef QCSCM_DEBUG

void
qcscm_uefi_dump_variables(struct qcscm_softc *sc)
{
        efi_char name[128];
        struct uuid guid;
        int namesize = sizeof(name);
        int i, ret;

        memset(name, 0, sizeof(name));
        memset(&guid, 0, sizeof(guid));

        for (;;) {
                ret = qcscm_uefi_get_next_variable(sc, name, &namesize, &guid);
                if (ret == 0) {
                        printf("%s: ", device_xname(sc->sc_dev));
                        for (i = 0; i < namesize / 2; i++)
                                printf("%c", name[i]);
                        printf(" { 0x%08x, 0x%04x, 0x%04x, { ",
                           guid.time_low, guid.time_mid, guid.time_hi_and_version);
                        printf(" 0x%02x, 0x%02x,",
                           guid.clock_seq_hi_and_reserved,
                           guid.clock_seq_low);
                        for (i = 0; i < 6; i++) {
                                printf(" 0x%02x,", guid.node[i]);
                        }
                        printf(" }");
                        printf("\n");
                        namesize = sizeof(name);
                        continue;
                }
                break;
        }
}

void
qcscm_uefi_dump_variable(struct qcscm_softc *sc, efi_char *name, int namesize,
    struct uuid *guid)
{
        uint8_t data[512];
        int datasize = sizeof(data);
        int i, ret;

        ret = qcscm_uefi_get_variable(sc, name, namesize, guid,
            NULL, data, &datasize);
        if (ret != QCTEE_UEFI_SUCCESS) {
                printf("%s: error reading ", device_xname(sc->sc_dev));
                for (i = 0; i < namesize / 2; i++)
                        printf("%c", name[i]);
                printf("\n");
                return;
        }

        printf("%s: ", device_xname(sc->sc_dev));
        for (i = 0; i < namesize / 2; i++)
                printf("%c", name[i]);
        printf(" = ");
        for (i = 0; i < datasize; i++)
                printf("%02x", data[i]);
        printf("\n");
}

#endif

int
qcscm_uefi_rtc_get(uint32_t *off)
{
        struct qcscm_softc *sc = qcscm_sc;
        uint32_t rtcinfo[3];
        int rtcinfosize = sizeof(rtcinfo);

        if (sc == NULL)
                return ENXIO;

        if (qcscm_uefi_get_variable(sc, EFI_VAR_RTCINFO, sizeof(EFI_VAR_RTCINFO),
            &qcscm_uefi_rtcinfo_guid, NULL, (uint8_t *)rtcinfo,
            &rtcinfosize) != 0)
                return EIO;

        /* UEFI stores the offset based on GPS epoch */
        *off = rtcinfo[0] + UNIX_GPS_EPOCH_OFFSET;
        return 0;
}

int
qcscm_uefi_rtc_set(uint32_t off)
{
        struct qcscm_softc *sc = qcscm_sc;
        uint32_t rtcinfo[3];
        int rtcinfosize = sizeof(rtcinfo);

        if (sc == NULL)
                return ENXIO;

        if (qcscm_uefi_get_variable(sc, EFI_VAR_RTCINFO, sizeof(EFI_VAR_RTCINFO),
            &qcscm_uefi_rtcinfo_guid, NULL, (uint8_t *)rtcinfo,
            &rtcinfosize) != 0)
                return EIO;

        /* UEFI stores the offset based on GPS epoch */
        off -= UNIX_GPS_EPOCH_OFFSET;

        /* No need to set if we're not changing anything */
        if (rtcinfo[0] == off)
                return 0;

        rtcinfo[0] = off;

        if (qcscm_uefi_set_variable(sc, EFI_VAR_RTCINFO, sizeof(EFI_VAR_RTCINFO),
            &qcscm_uefi_rtcinfo_guid, EFI_VARIABLE_NON_VOLATILE |
            EFI_VARIABLE_BOOTSERVICE_ACCESS | EFI_VARIABLE_RUNTIME_ACCESS,
            (uint8_t *)rtcinfo, sizeof(rtcinfo)) != 0)
                return EIO;

        return 0;
}

int
qcscm_pas_init_image(uint32_t peripheral, paddr_t metadata)
{
        struct qcscm_softc *sc = qcscm_sc;
        uint64_t res[3];
        uint64_t args[2];
        uint32_t arginfo;
        int ret;

        if (sc == NULL)
                return ENXIO;

        arginfo = QCSCM_ARGINFO_NUM(__arraycount(args));
        arginfo |= QCSCM_ARGINFO_TYPE(0, QCSCM_ARGINFO_TYPE_VAL);
        arginfo |= QCSCM_ARGINFO_TYPE(1, QCSCM_ARGINFO_TYPE_RW);
        args[0] = peripheral;
        args[1] = metadata;

        /* Make call into TEE */
        ret = qcscm_smc_call(sc, ARM_SMCCC_OWNER_SIP, QCSCM_SVC_PIL,
            QCSCM_PIL_PAS_INIT_IMAGE, arginfo, args, __arraycount(args), res);

        /* If the call succeeded, check the response status */
        if (ret == 0)
                ret = res[0];

        return ret;
}

int
qcscm_pas_mem_setup(uint32_t peripheral, paddr_t addr, size_t size)
{
        struct qcscm_softc *sc = qcscm_sc;
        uint64_t res[3];
        uint64_t args[3];
        uint32_t arginfo;
        int ret;

        if (sc == NULL)
                return ENXIO;

        arginfo = QCSCM_ARGINFO_NUM(__arraycount(args));
        arginfo |= QCSCM_ARGINFO_TYPE(0, QCSCM_ARGINFO_TYPE_VAL);
        arginfo |= QCSCM_ARGINFO_TYPE(1, QCSCM_ARGINFO_TYPE_VAL);
        arginfo |= QCSCM_ARGINFO_TYPE(2, QCSCM_ARGINFO_TYPE_VAL);
        args[0] = peripheral;
        args[1] = addr;
        args[2] = size;

        /* Make call into TEE */
        ret = qcscm_smc_call(sc, ARM_SMCCC_OWNER_SIP, QCSCM_SVC_PIL,
            QCSCM_PIL_PAS_MEM_SETUP, arginfo, args, __arraycount(args), res);

        /* If the call succeeded, check the response status */
        if (ret == 0)
                ret = res[0];

        return ret;
}

int
qcscm_pas_auth_and_reset(uint32_t peripheral)
{
        struct qcscm_softc *sc = qcscm_sc;
        uint64_t res[3];
        uint64_t args[1];
        uint32_t arginfo;
        int ret;

        if (sc == NULL)
                return ENXIO;

        arginfo = QCSCM_ARGINFO_NUM(__arraycount(args));
        arginfo |= QCSCM_ARGINFO_TYPE(0, QCSCM_ARGINFO_TYPE_VAL);
        args[0] = peripheral;

        /* Make call into TEE */
        ret = qcscm_smc_call(sc, ARM_SMCCC_OWNER_SIP, QCSCM_SVC_PIL,
            QCSCM_PIL_PAS_AUTH_AND_RESET, arginfo, args, __arraycount(args), res);

        /* If the call succeeded, check the response status */
        if (ret == 0)
                ret = res[0];

        return ret;
}

int
qcscm_pas_shutdown(uint32_t peripheral)
{
        struct qcscm_softc *sc = qcscm_sc;
        uint64_t res[3];
        uint64_t args[1];
        uint32_t arginfo;
        int ret;

        if (sc == NULL)
                return ENXIO;

        arginfo = QCSCM_ARGINFO_NUM(__arraycount(args));
        arginfo |= QCSCM_ARGINFO_TYPE(0, QCSCM_ARGINFO_TYPE_VAL);
        args[0] = peripheral;

        /* Make call into TEE */
        ret = qcscm_smc_call(sc, ARM_SMCCC_OWNER_SIP, QCSCM_SVC_PIL,
            QCSCM_PIL_PAS_SHUTDOWN, arginfo, args, __arraycount(args), res);

        /* If the call succeeded, check the response status */
        if (ret == 0)
                ret = res[0];

        return ret;
}

/* DMA code */
struct qcscm_dmamem *
qcscm_dmamem_alloc(struct qcscm_softc *sc, bus_size_t size, bus_size_t align)
{
        struct qcscm_dmamem *qdm;
        int nsegs;

        qdm = kmem_zalloc(sizeof(*qdm), KM_SLEEP);
        qdm->qdm_size = size;

        if (bus_dmamap_create(sc->sc_dmat, size, 1, size, 0,
            BUS_DMA_WAITOK | BUS_DMA_ALLOCNOW, &qdm->qdm_map) != 0)
                goto qdmfree;

        if (bus_dmamem_alloc(sc->sc_dmat, size, align, 0,
            &qdm->qdm_seg, 1, &nsegs, BUS_DMA_WAITOK) != 0)
                goto destroy;

        if (bus_dmamem_map(sc->sc_dmat, &qdm->qdm_seg, nsegs, size,
            &qdm->qdm_kva, BUS_DMA_WAITOK | BUS_DMA_COHERENT) != 0)
                goto free;

        if (bus_dmamap_load(sc->sc_dmat, qdm->qdm_map, qdm->qdm_kva, size,
            NULL, BUS_DMA_WAITOK) != 0)
                goto unmap;

        memset(qdm->qdm_kva, 0, size);

        return (qdm);

unmap:
        bus_dmamem_unmap(sc->sc_dmat, qdm->qdm_kva, size);
free:
        bus_dmamem_free(sc->sc_dmat, &qdm->qdm_seg, 1);
destroy:
        bus_dmamap_destroy(sc->sc_dmat, qdm->qdm_map);
qdmfree:
        kmem_free(qdm, sizeof(*qdm));

        return (NULL);
}

void
qcscm_dmamem_free(struct qcscm_softc *sc, struct qcscm_dmamem *qdm)
{
        bus_dmamem_unmap(sc->sc_dmat, qdm->qdm_kva, qdm->qdm_size);
        bus_dmamem_free(sc->sc_dmat, &qdm->qdm_seg, 1);
        bus_dmamap_destroy(sc->sc_dmat, qdm->qdm_map);
        kmem_free(qdm, sizeof(*qdm));
}