/* $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/queue.h>
#include <sys/malloc.h>
#include <sys/sysctl.h>
#include <sys/device.h>
#include <sys/evcount.h>
#include <sys/socket.h>
#include <sys/timeout.h>
#include <sys/atomic.h>

#include <uvm/uvm_extern.h>

#include <machine/intr.h>
#include <machine/bus.h>
#include <machine/fdt.h>

#include <dev/efi/efi.h>
#include <machine/efivar.h>

#include <dev/ofw/openfirm.h>
#include <dev/ofw/ofw_misc.h>
#include <dev/ofw/fdt.h>

#include "efi.h"

/* #define QCSCM_DEBUG */

#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_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

struct qcscm_dmamem {
        bus_dmamap_t            qdm_map;
        bus_dma_segment_t       qdm_seg;
        size_t                  qdm_size;
        caddr_t                 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)     ((void *)(_qdm)->qdm_kva)

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

struct qcscm_softc {
        struct device           sc_dev;
        int                     sc_node;
        bus_dma_tag_t           sc_dmat;

        struct qcscm_dmamem     *sc_extarg;
        uint32_t                sc_uefi_id;
};

int     qcscm_match(struct device *, void *, void *);
void    qcscm_attach(struct device *parent, struct device *self, void *args);

const struct cfattach   qcscm_ca = {
        sizeof (struct qcscm_softc), qcscm_match, qcscm_attach
};

struct cfdriver qcscm_cd = {
        NULL, "qcscm", DV_DULL
};

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 *, CHAR16 *,
            int, EFI_GUID *, uint32_t *, uint8_t *, int *);
EFI_STATUS qcscm_uefi_set_variable(struct qcscm_softc *, CHAR16 *,
            int, EFI_GUID *, uint32_t, uint8_t *, int);
EFI_STATUS qcscm_uefi_get_next_variable(struct qcscm_softc *,
            CHAR16 *, int *, EFI_GUID *);

EFI_STATUS qcscm_efi_get_variable(CHAR16 *, EFI_GUID *, UINT32 *,
            UINTN *, VOID *);
EFI_STATUS qcscm_efi_set_variable(CHAR16 *, EFI_GUID *, UINT32,
            UINTN, VOID *);
EFI_STATUS qcscm_efi_get_next_variable_name(UINTN *, CHAR16 *, EFI_GUID *);

#ifdef QCSCM_DEBUG
void    qcscm_uefi_dump_variables(struct qcscm_softc *);
void    qcscm_uefi_dump_variable(struct qcscm_softc *, CHAR16 *, int,
            EFI_GUID *);
#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;

int
qcscm_match(struct device *parent, void *match, void *aux)
{
        struct fdt_attach_args *faa = aux;

        return OF_is_compatible(faa->fa_node, "qcom,scm");
}

void
qcscm_attach(struct device *parent, struct device *self, void *aux)
{
        struct qcscm_softc *sc = (struct qcscm_softc *)self;
        struct fdt_attach_args *faa = aux;

        sc->sc_node = faa->fa_node;
        sc->sc_dmat = faa->fa_dmat;

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

        if (qcscm_tee_app_get_id(sc, "qcom.tz.uefisecapp", &sc->sc_uefi_id)) {
                printf(": can't retrieve UEFI App\n");
                return;
        }

        printf("\n");
        qcscm_sc = sc;

#if NEFI > 0
        efi_get_variable = qcscm_efi_get_variable;
        efi_set_variable = qcscm_efi_set_variable;
        efi_get_next_variable_name = qcscm_efi_get_next_variable_name;
#endif

#ifdef QCSCM_DEBUG
        qcscm_uefi_dump_variables(sc);
        qcscm_uefi_dump_variable(sc, u"RTCInfo", sizeof(u"RTCInfo"),
            &qcscm_uefi_rtcinfo_guid);
#endif
}

/* Expects an uint64_t[8] */
void
qcscm_smc_exec(uint64_t *in, uint64_t *out)
{
        __asm(
            "ldp x0, x1, [%0, #0]\n"
            "ldp x2, x3, [%0, #16]\n"
            "ldp x4, x5, [%0, #32]\n"
            "ldp x6, x7, [%0, #48]\n"
            "ldp x8, x9, [%0, #64]\n"
            "ldp x10, x11, [%0, #80]\n"
            "ldp x12, x13, [%0, #96]\n"
            "ldp x14, x15, [%0, #112]\n"
            "ldp x16, x17, [%0, #128]\n"
            "smc #0\n"
            "stp x0, x1, [%1, #0]\n"
            "stp x2, x3, [%1, #16]\n"
            "stp x4, x5, [%1, #32]\n"
            "stp x6, x7, [%1, #48]\n"
            "stp x8, x9, [%1, #64]\n"
            "stp x10, x11, [%1, #80]\n"
            "stp x12, x13, [%1, #96]\n"
            "stp x14, x15, [%1, #112]\n"
            "stp x16, x17, [%1, #128]\n" ::
            "r" (in), "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;

        /* 4 of our 10 possible args fit into x2-x5 */
        smcreq[0] = ARM_SMCCC_STD_CALL | ARM_SMCCC_LP64 |
            owner << 24 | svc << 8 | cmd;
        smcreq[1] = arginfo;
        for (i = 0; i < min(arglen, 4); i++)
                smcreq[2 + i] = args[i];

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

        for (;;) {
                qcscm_smc_exec(smcreq, smcres);
                /* If the call gets interrupted, try again and re-pass x0/x6 */
                if (smcres[0] == QCSCM_INTERRUPTED) {
                        smcreq[0] = smcres[0];
                        smcreq[6] = smcres[6];
                        continue;
                }
                break;
        }

        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), name, strlen(name));

        /* Pass address of name and length */
        arginfo = QCSCM_ARGINFO_NUM(nitems(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);

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

        membar_sync();

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

        membar_sync();

        /* 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,
    CHAR16 *name, int name_size, EFI_GUID *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;

        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);

        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_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,
    CHAR16 *name, int name_size, EFI_GUID *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;

        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,
    CHAR16 *name, int *name_size, EFI_GUID *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;

        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;
}

#if NEFI > 0

EFI_STATUS
qcscm_efi_get_variable(CHAR16 *name, EFI_GUID *guid, UINT32 *attributes,
   UINTN *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(CHAR16 *name, EFI_GUID *guid, UINT32 attributes,
    UINTN 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(UINTN *name_size, CHAR16 *name,
    EFI_GUID *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));
}

#endif

#ifdef QCSCM_DEBUG

void
qcscm_uefi_dump_variables(struct qcscm_softc *sc)
{
        CHAR16 name[128];
        EFI_GUID 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: ", sc->sc_dev.dv_xname);
                        for (i = 0; i < namesize / 2; i++)
                                printf("%c", name[i]);
                        printf(" { 0x%08x, 0x%04x, 0x%04x, { ",
                           guid.Data1, guid.Data2, guid.Data3);
                        for (i = 0; i < 8; i++) {
                                printf(" 0x%02x,", guid.Data4[i]);
                        }
                        printf(" }");
                        printf("\n");
                        namesize = sizeof(name);
                        continue;
                }
                break;
        }
}

void
qcscm_uefi_dump_variable(struct qcscm_softc *sc, CHAR16 *name, int namesize,
    EFI_GUID *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 ", sc->sc_dev.dv_xname);
                for (i = 0; i < namesize / 2; i++)
                        printf("%c", name[i]);
                printf("\n");
                return;
        }

        printf("%s: ", sc->sc_dev.dv_xname);
        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, u"RTCInfo", sizeof(u"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, u"RTCInfo", sizeof(u"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, u"RTCInfo", sizeof(u"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(nitems(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, nitems(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(nitems(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, nitems(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(nitems(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, nitems(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(nitems(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, nitems(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 = malloc(sizeof(*qdm), M_DEVBUF, M_WAITOK | M_ZERO);
        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_range(sc->sc_dmat, size, align, 0,
            &qdm->qdm_seg, 1, &nsegs, BUS_DMA_WAITOK, 0, 0xffffffff) != 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;

        bzero(qdm->qdm_kva, 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:
        free(qdm, M_DEVBUF, 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);
        free(qdm, M_DEVBUF, sizeof(*qdm));
}