/* $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 <[email protected]>
*
* 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));
}