root/drivers/gpu/drm/nouveau/nvkm/engine/disp/uhead.c
/*
 * Copyright 2021 Red Hat Inc.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 * OTHER DEALINGS IN THE SOFTWARE.
 */
#define nvkm_uhead(p) container_of((p), struct nvkm_head, object)
#include "head.h"
#include <core/event.h>

#include <nvif/if0013.h>

#include <nvif/event.h>

static int
nvkm_uhead_uevent(struct nvkm_object *object, void *argv, u32 argc, struct nvkm_uevent *uevent)
{
        struct nvkm_head *head = nvkm_uhead(object);
        union nvif_head_event_args *args = argv;

        if (!uevent)
                return 0;
        if (argc != sizeof(args->vn))
                return -ENOSYS;

        return nvkm_uevent_add(uevent, &head->disp->vblank, head->id,
                               NVKM_DISP_HEAD_EVENT_VBLANK, NULL);
}

static int
nvkm_uhead_mthd_scanoutpos(struct nvkm_head *head, void *argv, u32 argc)
{
        union nvif_head_scanoutpos_args *args = argv;

        if (argc != sizeof(args->v0) || args->v0.version != 0)
                return -ENOSYS;

        head->func->state(head, &head->arm);
        args->v0.vtotal  = head->arm.vtotal;
        args->v0.vblanks = head->arm.vblanks;
        args->v0.vblanke = head->arm.vblanke;
        args->v0.htotal  = head->arm.htotal;
        args->v0.hblanks = head->arm.hblanks;
        args->v0.hblanke = head->arm.hblanke;

        /* We don't support reading htotal/vtotal on pre-NV50 VGA,
         * so we have to give up and trigger the timestamping
         * fallback in the drm core.
         */
        if (!args->v0.vtotal || !args->v0.htotal)
                return -ENOTSUPP;

        args->v0.time[0] = ktime_to_ns(ktime_get());
        head->func->rgpos(head, &args->v0.hline, &args->v0.vline);
        args->v0.time[1] = ktime_to_ns(ktime_get());
        return 0;
}

static int
nvkm_uhead_mthd(struct nvkm_object *object, u32 mthd, void *argv, u32 argc)
{
        struct nvkm_head *head = nvkm_uhead(object);

        switch (mthd) {
        case NVIF_HEAD_V0_SCANOUTPOS: return nvkm_uhead_mthd_scanoutpos(head, argv, argc);
        default:
                return -EINVAL;
        }
}

static void *
nvkm_uhead_dtor(struct nvkm_object *object)
{
        struct nvkm_head *head = nvkm_uhead(object);
        struct nvkm_disp *disp = head->disp;

        spin_lock(&disp->client.lock);
        head->object.func = NULL;
        spin_unlock(&disp->client.lock);
        return NULL;
}

static const struct nvkm_object_func
nvkm_uhead = {
        .dtor = nvkm_uhead_dtor,
        .mthd = nvkm_uhead_mthd,
        .uevent = nvkm_uhead_uevent,
};

int
nvkm_uhead_new(const struct nvkm_oclass *oclass, void *argv, u32 argc, struct nvkm_object **pobject)
{
        struct nvkm_disp *disp = nvkm_udisp(oclass->parent);
        struct nvkm_head *head;
        union nvif_head_args *args = argv;
        int ret;

        if (argc != sizeof(args->v0) || args->v0.version != 0)
                return -ENOSYS;
        if (!(head = nvkm_head_find(disp, args->v0.id)))
                return -EINVAL;

        ret = -EBUSY;
        spin_lock(&disp->client.lock);
        if (!head->object.func) {
                nvkm_object_ctor(&nvkm_uhead, oclass, &head->object);
                *pobject = &head->object;
                ret = 0;
        }
        spin_unlock(&disp->client.lock);
        return ret;
}